JBJS | Arthrodesis as an Early Alternative to Nonoperative Management of Charcot Arthropathy of the Diabetic Foot*

The Journal of Bone & Joint Surgery, Volume 82, Issue 7

Articles | July 01, 2000

Arthrodesis as an Early Alternative to Nonoperative Management of Charcot Arthropathy of the Diabetic Foot*

SHELDON R. SIMON, M.D.†; SAMIR G. TEJWANI, M.D.‡; DEBORAH L. WILSON, M.D.§; THOMAS J. SANTNER, Ph.D.#; NANCY L. DENNISTON, M.S.**

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Investigation performed at the Department of Orthopaedic Surgery, Ohio State University College of Medicine, Columbus, Ohio
*No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. Funds were received in total or partial support of the research or clinical study presented in this article. The funding sources were Grant H133E30009 from the National Institute on Disability and Rehabilitation Research of the Department of Education and the Samuel J. Roessler Memorial Scholarship Fund.
†Department of Orthopaedic Surgery, Beth Israel Medical Center, 170 East End Avenue, New York, N.Y. 10128. E-mail address: ssimon@bethisraelny.org.
‡Department of Orthopaedic Surgery, University of California at Los Angeles School of Medicine, Center for the Health Sciences, Box 956902, Los Angeles, California 90095-6902. E-mail address: samtejwani@yahoo.com.
§Department of Medical Education, Grant Medical Center, 111 South Grant Avenue, Columbus, Ohio 43215. E-mail address: whonoops@aol.com.
#Department of Statistics, Ohio State University, 405 Cockins Hall, 1958 Neil Avenue, Columbus, Ohio 43210. E-mail address: santner.1@osu.edu.
**The Center for Gait and Movement Analysis, The Children's Hospital, 1056 East 19th Avenue, Box 476, Denver, Colorado 80218. E-mail address: denniston.nancy@tchden.org.

The Journal of Bone & Joint Surgery. 2000; 82:939-939

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Abstract

Background: This study was performed to evaluate the use of arthrodesis of the tarsal-metatarsal area for the treatment of Eichenholtz stage-I Charcot arthropathy in patients with diabetes. Currently, the standard treatment of stage-I Charcot arthropathy is the application of a non-weight-bearing total-contact cast. Although this treatment can be effective for allowing a patient to walk without undergoing an operation, a nonunion or malunion may still result. The subsequent deformities may lead to complications, including ulceration of the foot and the need for operative intervention. Recently, a group of patients who had had early operative intervention for a variety of reasons provided us with the opportunity to objectively evaluate the effects of such treatment. This analysis provided valuable information about whether this treatment is a reasonable alternative to current nonoperative approaches.

Methods: Between January 1991 and December 1996, fourteen patients had an operation because of Eichenholtz stage-I diabetic neuropathy. The classification of the disease as Eichenholtz stage I (the developmental stage) was based on radiographic evidence of varying degrees of articular-surface and subchondral-bone resorption and fragmentation as well as joint subluxation or dislocation without evidence of coalescence or callus formation. The operative procedure consisted of extensive dè¡²idement, open reduction, and internal fixation of the tarsal-metatarsal region with autologous bone graft. Postoperative treatment consisted of immobilization of the limb in a non-weight-bearing cast for a minimum of six weeks. All of the patients returned for a final follow-up visit at a mean of forty-one months (range, 25.3 to 77.3 months) postoperatively, at which time clinical and radiographic evaluations as well as gait analysis (with measurement of plantar pressures) were performed. The gait-analysis data was compared with similar data from a group of fourteen patients with diabetic neuropathy who had had a below-the-knee amputation and with that from a group of fourteen patients with diabetic neuropathy who had no history of plantar ulceration.

Results: All of the arthrodesis procedures were successful. Clinically, none of the patients had immediate or long-term complications postoperatively. No patient reported ulceration after the operation. The mean time to assisted weight-bearing was 10 ± 3.3 weeks (range, six to fifteen weeks), the mean time to unassisted weight-bearing was 15 ±8.8 weeks (range, eight to thirty-four weeks), and the mean time to return to the use of regular shoes was 27 ±14.4 weeks (range, twelve to sixty weeks). All of the patients regained the level of walking ability that they had had prior to the arthropathy. The calculated confidence intervals revealed no differences between the arthrodesis group and either of the two comparison groups with regard to the time-distance gait parameters of velocity, cadence, and stride length or with regard to the minimum, maximum, and total range of motion of each of the joints. In contrast to able-bodied subjects, all three groups showed a reduction in sagittal-plane ankle motion that was primarily related to loss of plantar flexion. The first metatarsal, great toe, and heel showed the highest peak plantar pressures, with little difference among the groups.

Conclusions: To our knowledge, the present study is the first to demonstrate the potential for early operative treatment to restore anatomical alignment and improve function of diabetic patients with stage-I Charcot arthropathy.

Figures in this Article

Introduction

Introduction | Materials and Methods | Results | Discussion | References

Neuropathic (Charcot) arthropathy is a well recognized condition that most commonly affects the tarsal-metatarsal and tarsal joints of patients with diabetic neuropathy^{8,14,32-34,65}. Originally described by Charcot in 1868¹⁸, neuropathic arthropathy was first associated with diabetes in 1936 by Jordan⁴³. In patients with diabetes mellitus, the prevalence of this condition has been reported⁶⁴ as one in 680. Although neuropathic arthropathy may be the initial manifestation of diabetes⁵⁶, most commonly it is a late sequela of this disorder. Four factors are considered to be necessary in order for Charcot arthropathy to develop^{21,27-29,57,58,63,71}: (1) peripheral neuropathy, (2) unrecognized injury, (3) continued repetitive stress on injured structures, and (4) increased local blood flow. Excessive osteoclastic activity without a concomitant increase in osteoblastic function has also been documented in the Charcot foot³⁶. The relationship between these four factors and this unopposed osteoclastic activity is not known³⁶. Nevertheless, in the acute process, rapid destruction of the bone architecture and joint subluxation occur and lead to deformity.

Eichenholtz believed that "the appearance of the roentgenological features were sufficient to establish the diagnosis" of Charcot arthropathy³¹. He presented a classification system for Charcot arthropathy, based more on radiographic than on clinical findings, that described three "well defined" stages. In stage I (development), bone fragmentation and debris with joint disruption and dislocation all may be present. As he stated, "Roentgenograms of the early formative stage (stage I) of a Charcot joint show some evidence of debris formation usually beginning at the articular margins. Synovial biopsy at this point will demonstrate microscopic evidence of the debris embedded within the synovium and [is] pathognomonic of the disease. This will be followed by fragmentation of the subchondral bone and attached articular cartilage. As this process is repeated, further disruption and capsular distention results in subluxation or dislocation." In stage II (coalescence), the bone surrounding the joint becomes sclerotic, absorption of the fine debris occurs, and most of the large fragments may fuse together. In stage III (reconstruction and reconstitution), remodeling occurs with reduction of the sclerosis, so-called rounding of the major fragments, and some attempt at reformation of the joint architecture³¹. Eichenholtz hoped that providing an accurate appraisal of the various stages of development would help in determining both the prognosis of the disease and the optimal time for arthrodesis. He believed that the optimal time for an operation would either be early in stage I or late in stage III. However, the standard initial treatment of this disorder, regardless of stage, has been immobilization with a non-weight-bearing cast until bone consolidation and joint stability are confirmed both clinically and radiographically⁵⁵. Recently, arthrodesis has been described as an effective method of limb salvage for patients with Charcot arthropathy who have severe deformity and instability and for whom a cast or brace is not a treatment option and amputation seems inevitable^35,62. Clinical union and stability were achieved in eight of eight patients in one series⁶⁸, in twenty-seven (93 percent) of twenty-nine patients in a second study⁵⁵, and in ten of eleven patients in a third study¹¹. In another study, the procedure was successful in eighteen (86 percent) of twenty-one feet, ten of which had had plantar pressure ulcers at the time of presentation²⁵. In all, clinical union and stability were achieved after eighty-two (90 percent) of the ninety-one such procedures reported in previous studies^{2,11,20,22,25,55,68}.

Although the results of these studies are promising, arthrodesis is regarded as an option for the treatment of Charcot arthropathy in the coalescence and reconstruction phases only. The current belief is that an operation done during the acute, developmental stage will result in inadequate internal fixation because of fragmentation of bone and may contribute directly to destruction of the joint architecture^47,55. Although in most cases the use of a total-contact cast can be effective for allowing a patient to walk without undergoing an operation¹, there are drawbacks to this conservative method of treatment. Treatment with a total-contact cast limits the ability of a patient to function on a day-to-day basis for an extended period of time. Patients in whom acute Charcot arthropathy resolves by spontaneous fusion are often left with gross deformities of the foot and ankle. As in the case of a Lisfranc fracture-dislocation that is treated nonoperatively, if fusion eventually occurs, normal anatomical relationships may not be restored as the subluxation or dislocation often cannot be reduced or held in a reduced position. These deformities may lead to complications, including ulceration of the foot and the need for subsequent operative intervention⁶². Lastly, as Eichenholtz suggested, the process of healing may "grind to a halt," resulting in a nonunion. Neither a nonunion nor a malunion should be considered an acceptable result. We report the clinical and functional results that were achieved after operative treatment of Eichenholtz stage-I Charcot arthropathy in diabetic patients. To our knowledge, the present study is the first to demonstrate successful results after such treatment.

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Fig. 1-A:: Figs. 1-A through 1-D: Radiographs of four different individuals, representing the spectrum of changes that we found in our patients with Eichenholtz stage-I Charcot arthropathy.
Fig. 1-A: Bone resorption is apparent at the bases of the first and second metatarsals as well as in the medial and middle cuneiform bones. Bone fragmentation is present between the first and second metatarsals (with subluxation of the joint) (arrow A), in the medial and middle cuneiform bones, and in the joint between the navicular and the medial cuneiform (arrow B). No changes are noted in the lateral tarsal-metatarsal area (arrow C).

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Fig. 1-B: Subluxation of the joint between the first and second metatarsals is similar to that in Fig. 1-A, but resorption and fragmentation in this area is not as prominent (arrow A). More bone resorption is present at the joint between the navicular and the medial cuneiform (arrow B). Little change is evident in the lateral tarsal-metatarsal area (arrow C).

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Fig. 1-C: Extensive bone resorption, fragmentation, and periarticular bone debris as well as subluxation is present along the tarsal-metatarsal joints of the medial longitudinal column (arrows A) and the joints between the lateral cuneiform and the second and third metatarsals (arrow C). Little change is noted in the joint between the navicular and the medial cuneiform (arrow B).

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Fig. 1-D: Extensive loss of the bone architecture of the lateral two cuneiforms (arrow A), the navicular (arrow B), and the bases of the second, third, and fourth metatarsals (arrow C) along with dislocation of the talonavicular and metatarsal-cuboid joints has produced a substantial midfoot deformity.

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Fig. 2:: Map of the right foot of a typical subject, showing the eleven mask regions (M) used in the measurement and analysis of plantar pressures.

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Fig. 3-A:: Figs. 3-A, 3-B, and 3-C: Anteroposterior, lateral, and oblique radiographs, made one year postoperatively, illustrating the reduction and fusion obtained in the foot shown preoperatively in Fig. 1-B.

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Fig. 3-B::

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Fig. 3-C::

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Table I: Demographic and Gait Data

*NA = not applicable.†The values are expressed as the mean and the standard deviation, with the range in parentheses.‡The values are expressed as the mean and the standard deviation. Negative values indicate that normal extension (0 degrees of extension at the hip and knee and 0 degrees of plantar flexion at the ankle) was not achieved.

	Group
Arthrodesis	Amputation	Diabetic- Neuropathy*
Demographic data
Gender (male/female) (no. of patients)	10/4	11/3	6/8
Diabetes (type I/type II) (no. of patients)	12/2	4/10	9/5
Involved side (right/left) (no. of patients)	8/6	6/8	NA
Cumulative Illness Rating Scale score†⁶⁰(points)	10.5 ±4.3 (2.0-14.0)	11.8 ±6.1 (4.0-20.0)	8.0 ±3.8 (2.0-11.0)
Age at op.† (yrs.)	48.2 ±9.5 (32.1-60.4)	56.5 ±13.0 (40.2-80.7)	NA
Duration of diabetes at op.†(yrs.)	22.1 ±9.0 (3.0-39.0)	20.8 ±8.4 (2.0-38.0)	NA
Age at testing†(yrs.)	50.7 ±8.8 (35.8-61.4)	58.8 ±12.5 (40.5-81.3)	52.1 ±11.3 (31.3-65.5)
Weight at testing† (kg)	88.4 ±22.8 (59.1-140.0)	88.9 ±20.2 (61.1-129.6)	88.8 ±20.2 (52.3-134.8)
Duration of diabetes at testing (yrs.)	24.6 ±9.2 (5.0-40.0)	23.1 ±10.2 (3.0-47.0)	21.1 ±11.1 (4.0-38.0)
Gait data
Cadence (steps/min.)	97.2 ±14.4	84.0 ±18.0	99.6 ±13.2
Stride length (m)	1.15 ±0.27	0.998 ±0.36	1.04 ±0.18
Velocity (m/sec.)	0.95 ±0.31	0.74 ±0.32	0.87 ±0.22
Pelvis (degrees)
Total range of motion	3.6 ±1.5	4.3 ±1.6	4.1 ±1.8
Maximum flexion	10.5 ±3.6	9.6 ±6.9	9.8 ±8.9
Maximum extension	-6.9 ±3.9	-5.5 ±6.7	-5.8 ±8.6
Hip (degrees)
Total range of motion	39.4 ±7.5	39.2 ±10.3	38.5 ±5.1
Maximum flexion	35.9 ±10.2	40.3 ±7.2	34.7 ±9.7
Maximum extension	3.6 ±6.6	-1.2 ±12.4	3.8 ±12.0
Knee (degrees)
Total range of motion	56.1 ±10.1	55.0 ±10.5	53.4 ±8.0
Maximum flexion	58.5 ±13.6	63.5 ±10.0	57.2 ±10.1
Maximum extension	-2.4 ±6.0	-8.5 ±7.4	-3.8 ±6.6
Ankle (degrees)
Total range of motion	18.4 ±5.6	14.5 ±6.9	20.3 ±4.4
Maximum dorsiflexion	13.4 ±4.4	13.8 ±5.7	13.6 ±5.6
Maximum plantar flexion	-2.7 ±8.0	-0.7 ±3.9	-6.3 ±5.8

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Table I: Demographic and Gait Data

	Group
Arthrodesis	Amputation	Diabetic- Neuropathy*
Demographic data
Gender (male/female) (no. of patients)	10/4	11/3	6/8
Diabetes (type I/type II) (no. of patients)	12/2	4/10	9/5
Involved side (right/left) (no. of patients)	8/6	6/8	NA
Cumulative Illness Rating Scale score†⁶⁰(points)	10.5 ±4.3 (2.0-14.0)	11.8 ±6.1 (4.0-20.0)	8.0 ±3.8 (2.0-11.0)
Age at op.† (yrs.)	48.2 ±9.5 (32.1-60.4)	56.5 ±13.0 (40.2-80.7)	NA
Duration of diabetes at op.†(yrs.)	22.1 ±9.0 (3.0-39.0)	20.8 ±8.4 (2.0-38.0)	NA
Age at testing†(yrs.)	50.7 ±8.8 (35.8-61.4)	58.8 ±12.5 (40.5-81.3)	52.1 ±11.3 (31.3-65.5)
Weight at testing† (kg)	88.4 ±22.8 (59.1-140.0)	88.9 ±20.2 (61.1-129.6)	88.8 ±20.2 (52.3-134.8)
Duration of diabetes at testing (yrs.)	24.6 ±9.2 (5.0-40.0)	23.1 ±10.2 (3.0-47.0)	21.1 ±11.1 (4.0-38.0)
Gait data
Cadence (steps/min.)	97.2 ±14.4	84.0 ±18.0	99.6 ±13.2
Stride length (m)	1.15 ±0.27	0.998 ±0.36	1.04 ±0.18
Velocity (m/sec.)	0.95 ±0.31	0.74 ±0.32	0.87 ±0.22
Pelvis (degrees)
Total range of motion	3.6 ±1.5	4.3 ±1.6	4.1 ±1.8
Maximum flexion	10.5 ±3.6	9.6 ±6.9	9.8 ±8.9
Maximum extension	-6.9 ±3.9	-5.5 ±6.7	-5.8 ±8.6
Hip (degrees)
Total range of motion	39.4 ±7.5	39.2 ±10.3	38.5 ±5.1
Maximum flexion	35.9 ±10.2	40.3 ±7.2	34.7 ±9.7
Maximum extension	3.6 ±6.6	-1.2 ±12.4	3.8 ±12.0
Knee (degrees)
Total range of motion	56.1 ±10.1	55.0 ±10.5	53.4 ±8.0
Maximum flexion	58.5 ±13.6	63.5 ±10.0	57.2 ±10.1
Maximum extension	-2.4 ±6.0	-8.5 ±7.4	-3.8 ±6.6
Ankle (degrees)
Total range of motion	18.4 ±5.6	14.5 ±6.9	20.3 ±4.4
Maximum dorsiflexion	13.4 ±4.4	13.8 ±5.7	13.6 ±5.6
Maximum plantar flexion	-2.7 ±8.0	-0.7 ±3.9	-6.3 ±5.8

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Table II: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for the Group Differences in Cadence, Stride Length, and Velocity

*More than three comparisons in each column.

Groups Compared	Cadence (steps/min.)	Stride Length (m)	Velocity (m/sec.)
Arthrodesis (affected side) and diabetic neuropathy (left side)	-25.92, 0.36	-0.305, 0.239	-0.347, 0.148
Amputation (affected side) and diabetic neuropathy (left side)	-15.72, 12.12	-0.093, 0.382	-0.198, 0.359
Amputation (affected side) and arthrodesis (affected side)	-27.12, 1.44	-0.411, 0.154	-0.539, 0.130

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Table II: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for the Group Differences in Cadence, Stride Length, and Velocity

*More than three comparisons in each column.

Groups Compared	Cadence (steps/min.)	Stride Length (m)	Velocity (m/sec.)
Arthrodesis (affected side) and diabetic neuropathy (left side)	-25.92, 0.36	-0.305, 0.239	-0.347, 0.148
Amputation (affected side) and diabetic neuropathy (left side)	-15.72, 12.12	-0.093, 0.382	-0.198, 0.359
Amputation (affected side) and arthrodesis (affected side)	-27.12, 1.44	-0.411, 0.154	-0.539, 0.130

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Table III: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for the Group Differences in,Maximum Minimum, and Total Joint Angles

*More than eight comparisons in each column.

Groups Compared	Maximum Angle (degrees)			Minimum Angle (degrees)			Total Range of Motion (degrees)
Hip	Knee	Ankle	Hip	Knee	Ankle	Hip	Knee	Ankle
Arthrodesis (affected side) and diabetic neuropathy (left side)	-10.83, 13.49	-8.55, 11.16	-5.80, 6.20	-9.79, 11.70	-9.314, 6.647	-2.78, 8.80	-5.09, 8.48	-6.91, 11.51	-7.22, 3.55
Arthrodesis (unaffected side) and diabetic neuropathy (left side)	-8.45, 15.40	-2.72, 13.83	-4.10, 10.91	-7.82, 12.46	-7.08, 11.03	-4.481, 8.17	-7.45, 9.30	-7.21, 13.16	-3.94, 5.39
Amputation (affected side) and diabetic neuropathy (left side)	-5.14,16.91	-5.55, 16.84	-6.47, 6.83	-9.99, 19.72	-4.24, 13.92	-0.225, 11.65	-7.63, 10.85	-9.64, 9.98	-13.18, 1.58
Amputation (unaffected side) and diabetic neuropathy (left side)	-6.49, 17.06	-4.92, 15.12	-2.88, 9.07	-12.36, 19.49	-3.243, 13.85	-5.259, 7.60	-5.98, 7.55	-8.32, 9.09	-3.98, 7.71
Amputation (affected side) and arthrodesis (affected side)	-5.14, 12.14	-7.19, 16.52	-5.58, 4.90	-8.54, 17.71	-2.470, 14.88	-1.994, 8.36	-10.45, 9.57	-12.55, 9.69	-11.45, 3.82
Amputation (affected side) and arthrodesis (unaffected side)	-7.25, 11.01	-10.29, 10.68	-9.56, 3.58	-8.69, 16.76	-6.44, 12.49	-1.366, 9.49	-10.91, 11.43	-13.35, 9.52	-13.69, 0.64
Amputation (unaffected side) and arthrodesis (affected side)	-7.18, 12.00	-6.95, 14.82	-2.43, 7.02	-10.59, 16.63	-0.965, 14.27	-6.249, 2.58	-8.59, 6.98	-11.21, 7.88	-2.45, 8.39
Amputation (unaffected side) and arthrodesis (unaffected side)	-8.71, 10.36	-9.64, 9.80	-5.89, 5.73	-10.79, 15.74	-5.31, 12.34	-5.60, 4.24	-9.23, 9.37	-13.63, 7.76	-4.73, 5.79

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Table III: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for the Group Differences in,Maximum Minimum, and Total Joint Angles

*More than eight comparisons in each column.

Groups Compared	Maximum Angle (degrees)			Minimum Angle (degrees)			Total Range of Motion (degrees)
Hip	Knee	Ankle	Hip	Knee	Ankle	Hip	Knee	Ankle
Arthrodesis (affected side) and diabetic neuropathy (left side)	-10.83, 13.49	-8.55, 11.16	-5.80, 6.20	-9.79, 11.70	-9.314, 6.647	-2.78, 8.80	-5.09, 8.48	-6.91, 11.51	-7.22, 3.55
Arthrodesis (unaffected side) and diabetic neuropathy (left side)	-8.45, 15.40	-2.72, 13.83	-4.10, 10.91	-7.82, 12.46	-7.08, 11.03	-4.481, 8.17	-7.45, 9.30	-7.21, 13.16	-3.94, 5.39
Amputation (affected side) and diabetic neuropathy (left side)	-5.14,16.91	-5.55, 16.84	-6.47, 6.83	-9.99, 19.72	-4.24, 13.92	-0.225, 11.65	-7.63, 10.85	-9.64, 9.98	-13.18, 1.58
Amputation (unaffected side) and diabetic neuropathy (left side)	-6.49, 17.06	-4.92, 15.12	-2.88, 9.07	-12.36, 19.49	-3.243, 13.85	-5.259, 7.60	-5.98, 7.55	-8.32, 9.09	-3.98, 7.71
Amputation (affected side) and arthrodesis (affected side)	-5.14, 12.14	-7.19, 16.52	-5.58, 4.90	-8.54, 17.71	-2.470, 14.88	-1.994, 8.36	-10.45, 9.57	-12.55, 9.69	-11.45, 3.82
Amputation (affected side) and arthrodesis (unaffected side)	-7.25, 11.01	-10.29, 10.68	-9.56, 3.58	-8.69, 16.76	-6.44, 12.49	-1.366, 9.49	-10.91, 11.43	-13.35, 9.52	-13.69, 0.64
Amputation (unaffected side) and arthrodesis (affected side)	-7.18, 12.00	-6.95, 14.82	-2.43, 7.02	-10.59, 16.63	-0.965, 14.27	-6.249, 2.58	-8.59, 6.98	-11.21, 7.88	-2.45, 8.39
Amputation (unaffected side) and arthrodesis (unaffected side)	-8.71, 10.36	-9.64, 9.80	-5.89, 5.73	-10.79, 15.74	-5.31, 12.34	-5.60, 4.24	-9.23, 9.37	-13.63, 7.76	-4.73, 5.79

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Table IV: Peak Plantar Foot Pressures in the Eleven Mask Regions of the Foot

*The values are expressed as the mean and the standard deviation.†The values are expressed as the mean.

Region	Amputation (Unaffected Side)* (N = 12)	Arthrodesis (Unaffected Side)* (N = 13)	Arthrodesis (Affected Side)* (N = 13)	Diabetic Neuropathy (Composite)† (N = 14)
Heel (Mask 1)	19.25 ±5.90	23.83 ±7.46	18.18 ±5.42	18.79
Midfoot
Medial aspect (Mask 11)	12.20 ±6.37	8.29 ±3.28	10.67 ±3.19	8.29
Lateral aspect (Mask 10)	12.22 ±5.41	10.03 ±4.33	13.00 ±6.62	10.90
Metatarsals
First (Mask 2)	26.42 ±15.6	23.08 ±8.51	25.10 ±14.9	23.38
Second (Mask 3)	18.75 ±5.55	18.95 ±6.57	15.97 ±6.35	20.98
Third (Mask 4)	18.11 ±8.60	17.13 ±7.14	14.68 ±8.76	19.41
Fourth (Mask 5)	16.06 ±8.63	14.18 ±5.66	12.69 ±7.26	16.10
Fifth (Mask 6)	10.78 ±5.49	10.04 ±4.88	11.83 ±8.68	12.59
Toes
Great (Mask 7)	21.22 ±15.3	20.06 ±10.7	14.87 ±10.5	11.29
Second (Mask 8)	12.78 ±7.58	12.93 ±5.29	9.17 ±6.02	11.12
Third (Mask 9)	9.39 ±4.07	10.22 ±5.28	6.00 ±4.76	10.29

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Table IV: Peak Plantar Foot Pressures in the Eleven Mask Regions of the Foot

*The values are expressed as the mean and the standard deviation.†The values are expressed as the mean.

Region	Amputation (Unaffected Side)* (N = 12)	Arthrodesis (Unaffected Side)* (N = 13)	Arthrodesis (Affected Side)* (N = 13)	Diabetic Neuropathy (Composite)† (N = 14)
Heel (Mask 1)	19.25 ±5.90	23.83 ±7.46	18.18 ±5.42	18.79
Midfoot
Medial aspect (Mask 11)	12.20 ±6.37	8.29 ±3.28	10.67 ±3.19	8.29
Lateral aspect (Mask 10)	12.22 ±5.41	10.03 ±4.33	13.00 ±6.62	10.90
Metatarsals
First (Mask 2)	26.42 ±15.6	23.08 ±8.51	25.10 ±14.9	23.38
Second (Mask 3)	18.75 ±5.55	18.95 ±6.57	15.97 ±6.35	20.98
Third (Mask 4)	18.11 ±8.60	17.13 ±7.14	14.68 ±8.76	19.41
Fourth (Mask 5)	16.06 ±8.63	14.18 ±5.66	12.69 ±7.26	16.10
Fifth (Mask 6)	10.78 ±5.49	10.04 ±4.88	11.83 ±8.68	12.59
Toes
Great (Mask 7)	21.22 ±15.3	20.06 ±10.7	14.87 ±10.5	11.29
Second (Mask 8)	12.78 ±7.58	12.93 ±5.29	9.17 ±6.02	11.12
Third (Mask 9)	9.39 ±4.07	10.22 ±5.28	6.00 ±4.76	10.29

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Table V: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for Peak Plantar Pressure in Six Mask Regions of the Foot

*More than five comparisons in each column.

Groups Compared	First Metatarsal (Mask 2)	Third Metatarsal (Mask 4)	Fifth Metatarsal (Mask 6)	Great Toe (Mask 7)	Lateral Aspect of Midfoot (Mask 10)	Medial Aspect of Midfoot (Mask 11)
Arthrodesis (affected side) and diabetic neuropathy (left side)	-11.00, 16.00	-16.00, 0.00	-9.00, 5.99	-8.00, 13.00	-6.00, 5.99	-2.00, 5.99
Arthrodesis (unaffected side) and diabetic neuropathy (left side)	-6.00, 13.00	-14.00, 5.00	-10.00, 0.00	-1.00, 23.00	-9.00, 3.00	-5.00, 4.00
Amputation (unaffected side) and diabetic neuropathy (left side)	-9.01, 11.99	-14.00, 4.00	-10.00, 1.00	-1.00, 21.00	-6.00, 6.00	-2.00, 9.00
Amputation (unaffected side) and arthrodesis (affected side)	-18.01, 15.99	-6.01, 10.00	-12.00, 4.00	-7.01, 20.01	-6.00, 7.00	-3.99, 8.00
Amputation (unaffected side) and arthrodesis (unaffected side)	-14.00, 11.00	-11.00, 9.00	-3.99, 4.00	-14.99, 13.00	-3.00, 10.00	-0.99, 10.00

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Table V: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for Peak Plantar Pressure in Six Mask Regions of the Foot

*More than five comparisons in each column.

Groups Compared	First Metatarsal (Mask 2)	Third Metatarsal (Mask 4)	Fifth Metatarsal (Mask 6)	Great Toe (Mask 7)	Lateral Aspect of Midfoot (Mask 10)	Medial Aspect of Midfoot (Mask 11)
Arthrodesis (affected side) and diabetic neuropathy (left side)	-11.00, 16.00	-16.00, 0.00	-9.00, 5.99	-8.00, 13.00	-6.00, 5.99	-2.00, 5.99
Arthrodesis (unaffected side) and diabetic neuropathy (left side)	-6.00, 13.00	-14.00, 5.00	-10.00, 0.00	-1.00, 23.00	-9.00, 3.00	-5.00, 4.00
Amputation (unaffected side) and diabetic neuropathy (left side)	-9.01, 11.99	-14.00, 4.00	-10.00, 1.00	-1.00, 21.00	-6.00, 6.00	-2.00, 9.00
Amputation (unaffected side) and arthrodesis (affected side)	-18.01, 15.99	-6.01, 10.00	-12.00, 4.00	-7.01, 20.01	-6.00, 7.00	-3.99, 8.00
Amputation (unaffected side) and arthrodesis (unaffected side)	-14.00, 11.00	-11.00, 9.00	-3.99, 4.00	-14.99, 13.00	-3.00, 10.00	-0.99, 10.00

Materials and Methods

Introduction | Materials and Methods | Results | Discussion | References

Patient Selection

Between January 1991 and December 1996, the senior author (S. R. S.) managed forty-three diabetic patients who had clinical and radiographic evidence of Eichenholtz stage-I Charcot arthropathy³¹. All patients presented with a profoundly swollen, warm, erythematous foot. As these clinical signs are nonspecific, stage-I Charcot arthropathy was diagnosed mainly on the basis of radiographic findings. Radiographs of the involved area showed a spectrum of changes, including bone resorption, osteochondral fragmentation, and the formation of periarticular bone debris (Fig. 1-A,Fig. 1-B,Fig. 1-C, and Fig. 1-D). The most extensive cases were characterized by joint subluxation or dislocation with fracture or osteochondral bone fragmentation in the midfoot area. We classified the anatomical pattern of joint involvement according to the system proposed by Sammarco and Conti⁶². Pattern 1 involves diastasis between the first and second metatarsals with fragmentation and collapse extending across the tarsometatarsal joint. Pattern 2 involves medial metatarsal-cuneiform destructive changes without diastasis between the first and second metatarsals. Pattern 3 refers to arthropathy at the navicular-medial cuneiform joint with fragmentation of the middle cuneiform bone and destruction across the lateral tarsometatarsal joints. Pattern 4 involves arthropathy of the first metatarsal-medial cuneiform joint with diastasis between the first and second metatarsals, with proximal and lateral extension in the intercuneiform joints ending at the calcaneocuboid joint. Finally, pattern 5 is described as perinavicular arthropathy with distal intertarsal extension. Twenty-nine of the forty-three patients were treated with immobilization of the affected limb in a total-contact cast and with restriction of walking and other activities. The remaining fourteen subjects requested operative treatment as an alternative to the classic nonoperative measures that had been recommended. Their prime reason for wanting operative intervention included knowledge of the difficulties associated with a deformed foot, such as the increased risk of ulceration and the difficulties with shoe-wear (two patients); the need for a kidney transplantation and physician concern regarding fluid shifts, cast care, subsequent medications, and wound-healing (seven patients); and functional and occupational difficulties associated with prolonged immobilization of the involved limb in a non-weight-bearing cast (five patients). Most of the individuals cited more than one of these reasons. Each patient elected operative intervention after much discussion of the risks. Informed consent for participation in this study was obtained in accordance with the policies of the Human Subjects Committee of the hospital Institutional Review Board.

All of the subjects had diabetic neuropathy as confirmed by a lack of sensation to the 5.07 Semmes-Weinstein monofilament⁵¹. Neither secondary diabetic complications (such as coronary atherosclerosis, retinopathy, and chronic renal failure with or without resultant renal dialysis or transplantation) nor the type of medications prescribed (such as steroids and Imuran [azathioprine]) were considered a contraindication to operating on the foot. A bone scan and an indium-labeled white blood-cell scan were performed prior to the operation when osteomyelitis was suspected¹⁵. In addition, the transcutaneous oxygen level was measured and a Doppler examination was performed to confirm the presence of an adequate blood supply. Histopathological analysis of representative specimens obtained at the time of the procedure confirmed the diagnosis of stage-I Charcot arthropathy on the basis of the pathognomonic appearance of bone debris embedded in the synovial tissue^15,31.

Operative Treatment

The senior author (S. R. S.) used the same technique for all of the operative procedures. Standard positioning for an operation on the foot and ankle was used. An Esmarch bandage was applied just proximal to the ankle to serve as a tourniquet. At least two but no more than three dorsal longitudinal incisions were made over the foot. The most medial incision was located medial to the extensor hallucis longus and was made sufficiently long to allow exposure of the medial side of the foot for insertion of a plate and screws or screws alone. The other incision or incisions were approximately four centimeters in length; one was located over the space between the second and third metatarsals, lateral to the palpable artery, and the other (which was only used on occasion) was located over the fourth metatarsal-cuboid area. The areas were examined, and ligaments, articular cartilage, loose callus, and fibrous tissue were excised to provide a good bed for arthrodesis. Autologous cancellous bone graft from the ilium (ten patients) or the proximal aspect of the tibia (four patients) was inserted in all of the joint spaces, and manual reduction was then performed.

Guide-pins or Kirschner wires were inserted to maintain the reduction temporarily, and fluoroscopic examination was used to confirm the adequacy of the reduction. After the reduction, we placed additional bone-graft material in the areas between any bones that still lacked contact. With use of standard AO techniques, titanium screws and plates or screws alone were inserted from the medial and dorsal directions to ensure that a stable reduction was maintained and that compression was present across as many arthrodesis sites as possible. The size and placement of the plate and screws depended on the nature of the areas of the midfoot involved, the severity of the subluxations or dislocations, and the amount of bone fragmentation. In all cases, stabilizing the medial column and the medial-to-lateral column with a plate and screws or screws alone adequately secured the reduction. Following plating, the adequacy of the reduction was reconfirmed with fluoroscopic imaging in at least three planes, the temporary guide-pins or Kirschner wires were removed, and all of the wounds were closed in layers with sutures. A well padded, below-the-knee, non-weight-bearing fiberglass cast was applied. Anteroposterior, lateral, and oblique radiographs of the foot were made.

Prophylactic antibiotics were administered intravenously before the procedure and during the first twenty-four hours thereafter. In all cases, at least one broad-spectrum antibiotic was used. However, the number of antibiotics and the nature and dose of each antibiotic varied for each patient depending on his or her medical history and medical condition at the time of the operation. The leg was repeatedly examined during the period of postoperative hospitalization. If excessive swelling or a change in color or temperature was noted, the cast was bivalved and removed and the foot was checked to ensure that the wound, skin, and circulation were not jeopardized. The patient remained in the hospital until the blood-glucose level returned to the preoperative value, the viability of the foot was confirmed, and the patient adequately performed non-weight-bearing transfers and was able to walk. In most cases, a walker or wheelchair was used as the assistive device instead of crutches because of involvement of the upper extremities with diabetic neuropathy.

Postoperatively, all of the patients were seen weekly for the first month, every two weeks for the second month, and at monthly intervals thereafter until healing was complete. At each visit, the cast was removed; the wounds, skin, and circulation were checked; and anteroposterior, lateral, and oblique radiographs of the foot were made. The involved limb remained in a non-weight-bearing cast until radiographs revealed sufficient evidence of bone-graft incorporation and callus formation at all of the arthrodesis sites; at that point, the patient was allowed to bear weight in a fiberglass cast for four weeks. If radiographs then showed further bone incorporation without adverse effects, the patient wore a weight-bearing cast-boot for an additional month. When there was no evidence of increased warmth or swelling in the lower extremity, the boot was discarded. Each patient returned for routine evaluation of the foot approximately every six months.

Study Parameters and Comparison Groups

The present study was performed to evaluate four factors related to the treatment of Charcot arthropathy: (1) the clinical result of early arthrodesis, (2) the financial costs to the patient and the health-insurance system, (3) the walking patterns after such an operation, and (4) the presence or absence of abnormal foot pressures after the operation that might increase the risk of ulceration of the ipsilateral or contralateral foot.

Because the operative goals included preventing deformities, restoring the gait parameters to their levels before the arthropathy, and decreasing the risk of plantar ulceration, we compared our patients with a group of subjects who had neuropathic diabetes but no history of plantar ulceration rather than with able-bodied individuals or with the twenty-nine diabetic patients with Eichenholtz stage-I Charcot arthropathy who had been treated nonoperatively. This comparison group consisted of fourteen age, height, weight, and gender-matched subjects with no clinical evidence of ulceration who were randomly selected from our orthopaedic diabetes clinic.

A second comparison group consisted of fourteen subjects with diabetic neuropathy who had had a below-the-knee amputation and who were followed clinically during the same period. The amputations had been performed because of osteomyelitis arising from neuropathic plantar ulceration or because of gangrene secondary to peripheral vascular disease, or both. Before the operation, the diagnosis was confirmed and the potential for wound-healing was evaluated with magnetic resonance imaging, vascular, and transcutaneous oxygenation studies. The amputation involved a standard myodesis-type procedure. All of the patients were fitted immediately with a prosthesis, and walking with partial weight-bearing was initiated within twenty-four hours after the operation. The protocol for postoperative visits for these patients was similar to that for the arthrodesis group.

In both of the comparison groups, diabetic neuropathy was confirmed by a lack of sensation to the 5.07 Semmes-Weinstein monofilament⁵¹. Because diabetes affects several organ systems, an indicator of comorbidity was determined for each subject and the groups were compared. Comorbidity was defined as the total burden of illness (such as diabetic neuropathy or coronary heart disease). It excluded Charcot arthropathy. Comorbidities were grouped according to the Cumulative Illness Rating Scale⁶⁰. This scale is based on the number of organ systems (categories) involved, the number of problems in each organ system, and a subjective analysis of the severity of each problem. The scale assigns a score of 0 to 4 points in each of thirteen categories: cardiac, vascular, respiratory, eye-ear-nose-throat, upper gastrointestinal, lower gastrointestinal, hepatic, renal, other genitourinary, musculoskeletal, neurological, psychiatric, and endocrine. A total score of 52 points is possible. The degree of comorbidity in each subject was determined by means of a retrospective review of the discharge and procedure summaries, progress notes, anesthesia notes, and hospital coding sheets for the date of the procedure.

A retrospective analysis of all financial charges was performed for the arthrodesis group and the amputation group. For each patient, the charges related to hospitalization for the operation, subsequent related operative interventions, orthopaedic follow-up visits, and, in the case of below-the-knee amputation patients, the costs of a limb prosthesis, were compiled from the billing records.

All of the subjects were asked to visit our clinic for a final evaluation at the time of this study. In addition to an interview and clinical and radiographic evaluation, each subject underwent gait analysis in order to determine the sagittal-plane motion of the pelvis, hip, knee, and ankle as well as the overall performance measures of velocity, stride length, and cadence. Our methods for acquiring and processing gait data have been described previously⁴⁵. During gait analysis, plantar pressures were measured with use of the Novel Pedar system (Novel, Munich, Germany)³⁷. Plantar pressures were measured in-shoe rather than barefoot. If present, custom shoe insoles were removed before data acquisition. With use of the Automask component of the Novel software, the regions potentially at risk for ulceration were defined by dividing the plantar aspect of the foot into eleven regions (Fig. 2): the heel; the medial aspect of the midfoot; the lateral aspect of the midfoot; the first, second, third, fourth, and fifth metatarsals; and the first, second, and third toes. Plantar pressures were measured in newtons per square centimeter.

During the time-period in which these evaluations were performed, the two comparison groups were examined in a similar manner. Three types of gait data (time-distance measurements, sagittal-plane motions of the lower extremity during gait, and foot-pressure parameters) were collected. The results were grouped according to diagnosis and side. This classification resulted in five subgroups (of fourteen limbs each) for statistical analysis: arthrodesis (affected side), arthrodesis (unaffected side), amputation (affected side), amputation (unaffected side), and diabetic neuropathy. The affected side was defined as the side that had been treated with an operation (arthrodesis or below-the-knee amputation) and the unaffected side, as the contralateral limb. The left limb was randomly chosen as the representative limb for the diabetic-neuropathy group. For the time-distance data, the statistical comparisons were made among the arthrodesis, amputation, and diabetic-neuropathy groups.

Means and standard deviations were evaluated for each of the time-distance parameters (cadence, velocity, and stride length) (Table I). The joint-angle data consisted of the maximum and minimum angles of joint motion at the hip, knee, and ankle and the total range of motion (calculated as the maximum angle in degrees minus the minimum angle in degrees) for each of these joints. Because the method of treatment had been determined on the basis of patient preference and clinical necessity rather than on the basis of random selection, this study is an observational one and not a clinical trial. As is appropriate for most observational studies, we elected to calculate confidence intervals for comparisons of the gait parameters of the various groups; confidence intervals show the range of values consistent with the data for each difference considered²³.

For the time-distance and joint-angle data, a preliminary inspection showed all of the responses to be non-gaussian. Thus, Hodges-Lehmann nonparametric confidence intervals based on the Wilcoxon-Mann-Whitney test were calculated for the time-distance parameters (cadence, velocity, and stride length), and a Bonferroni correction was used to provide the 95 percent simultaneous confidence intervals for the three comparisons (the arthrodesis group [affected side] compared with the diabetic-neuropathy group, the amputation group [affected side] compared with the diabetic-neuropathy group, and the arthrodesis group [affected side] compared with the amputation group [affected side])^39,41,46. For the joint-angle data, Hodges-Lehmann confidence intervals with a Bonferroni correction were calculated for the maximum, minimum, and total ranges of motion of each joint^39,41,46. This analysis involved eight comparisons: four in which the diabetic-neuropathy group were compared with the affected and unaffected sides from the arthrodesis and amputation groups, and four in which the affected and unaffected sides from the amputation group were compared with the affected and unaffected sides from the arthrodesis group.

The foot-pressure data was grouped with use of the Group Editor and Groupmask components of the Novel Pedar software. Foot-pressure data was evaluated for thirteen limbs in the arthrodesis group (affected side), for thirteen limbs in the arthrodesis group (unaffected side), for twelve limbs in the amputation group (unaffected side), and for fourteen limbs in the diabetic-neuropathy group. The foot-pressure data was excluded for four sides of three subjects (one subject from the arthrodesis group and two from the amputation group) because they had used a cane during testing. Plantar pressures were not evaluated for the prosthetic feet in the amputation group. The maximum peak plantar pressure was calculated in newtons per square centimeter for each individual in each of the eleven mask regions and for each of the test groups over three representative steps. This data was also non-gaussian. A single step for each subject was then selected at random for all further analyses. Although numerous authors have found the metatarsal region to be the most common site of plantar ulceration in the diabetic foot^{3,4,15,21,40,52,63,66,69}, there is lack of consensus about the specific metatarsal region that is most commonly involved in plantar ulceration, with a variety of sites (including the first metatarsal^3,21,52, third metatarsal⁶⁹, and fourth and fifth metatarsals⁶⁶) having been mentioned in previous reports. We therefore chose to study plantar pressure under the first, third, and fifth metatarsals; under the great toe; and under the lateral and medial aspects of the midfoot. For each of these areas, Hodges-Lehmann 95 percent simultaneous confidence intervals were constructed for the foot pressures in the four comparison groups.

Results

Introduction | Materials and Methods | Results | Discussion | References

Ten of the fourteen individuals in the arthrodesis group were male compared with eleven of the fourteen individuals in the amputation group (Table I). The mean duration of diabetes was similar for both groups. Neither group demonstrated a predominance with regard to the side of the operation. Most of the individuals in the arthrodesis group had type-I diabetes, whereas most of those in the amputation group had type-II diabetes. At the time of the operation, the mean age in the arthrodesis group was almost ten years lower than that in the amputation group. However, the mean Cumulative Illness Rating Score in the arthrodesis group (10.5 ±4.3 points; range, 2.0 to 14.0 points) was only slightly lower than that in the amputation group (11.8 ±6.1 points; range, 4.0 to 20.0 points) and that in the diabetic-neuropathy group (8.0 ± 3.8 points; range, 2.0 to 11.0 points).

Radiographs revealed that all of the patients in the arthrodesis group had Eichenholtz stage-I Charcot arthropathy. Analysis of the pattern of joint involvement according to the anatomical classification system of Sammarco and Conti⁶² revealed pattern 1 in three patients, pattern 2 in four, pattern 3 in one, and pattern 5 in one. One patient had a combination of patterns 2 and 3, and another had a combination of patterns 3 and 4. Three patients could not be classified with this system.

Independent of the pattern of presentation, all of the arthrodesis procedures were successful (Fig. 3-A,Fig. 3-B, and Fig. 3-C). Clinically, no patient had immediate or long-term complications after the operation or any evidence of superficial or deep infection, nonunion, or change in vascular status. Ten patients noted an improvement in sensation in the involved foot. The mean time to assisted weight-bearing was 10 ±3.3 weeks (range, six to fifteen weeks), the mean time to unassisted weight-bearing was 15 ±8.8 weeks (range, eight to thirty-four weeks), and the mean time to a return to the use of regular shoes was 27 ±14.4 weeks (range, twelve to sixty weeks).

The mean charge for operative treatment and orthopaedic follow-up was $13,511 ±$2727 (range, $9527 to $16,417) for twelve of the patients who had had an arthrodesis compared with $25,090 ±$8011 (range, $17,261 to $39,045) for eleven of the patients who had had a below-the-knee amputation. (Two of the patients in the arthrodesis group and three of the patients in the amputation group were excluded from this analysis because of incomplete financial records.) The variation in cost within each group was largely due to the time in the hospital that was necessary to ensure safe and independent walking rather than each individual's comorbidity rating. However, the higher cost in the amputation group was also related to the cost of the prosthetic devices.

All patients who had been managed operatively returned for a clinical examination and gait analysis. The mean time from the operation to this examination was forty-one months (range, 25.3 to 77.3 months) in the arthrodesis group and thirty-nine months (range, twenty-seven to 125 months) in the amputation group. All of the subjects who had had an arthrodesis returned to the levels of walking and functional activity that they had had prior to the arthropathy.

Compared with a population of able-bodied individuals who were tested in our laboratory, all of the individuals in the arthrodesis, amputation, and diabetic-neuropathy groups walked slower because of a shorter stride length as opposed to a change in cadence. The arthrodesis group showed the highest mean velocity (0.95 ± 0.31 meter per second), followed by the diabetic-neuropathy group (0.87 ±0.22 meter per second) and the amputation group (0.74 ±0.32 meter per second) (Table I). However, with the number of subjects available for study, the confidence intervals that were calculated for the comparison of mean velocity, cadence, and stride length demonstrated no evidence of statistical differences among the groups (Table II). Similarly, the 95 percent simultaneous confidence intervals that were calculated for the minimum, maximum, and total ranges of motion for each of the joints showed no evidence of statistical differences among the three groups (Table III). In all three groups, the range of motion of the ankle in the sagittal plane was restricted compared with that in the group of able-bodied subjects because of a mean reduction of plantar flexion of 16 degrees. No significant differences could be detected in the range of motion of any other joint. Overall, the ranges of motion of the hip and knee showed only small reductions, of about 5 to 10 degrees, compared with the ranges in our normal, able-bodied subjects.

No subject reported ulceration after the operation. In all of the groups, the highest peak plantar pressures were noted under the first metatarsal, the great toe, and the heel (Table IV). The confidence intervals that were calculated to compare the maximum peak plantar pressures among the groups on the unaffected side indicated that the pressure under the first metatarsal head was lower for the diabetic-neuropathy and arthrodesis groups than for the amputation group and that the pressure under the great toe was higher for the arthrodesis and amputation groups than for the diabetic-neuropathy group (Table V). There was no evidence of differences among the groups in any of the other areas.

Discussion

Introduction | Materials and Methods | Results | Discussion | References

In the United States, more than half of lower-extremity amputations are performed in patients with diabetes⁵⁴, and the most common finding leading to amputation in diabetic patients is a neuropathic ulcer of the foot⁴. In individuals with diabetes and sensory loss, excessive pressure from shoes or from weight-bearing is the most frequent cause of skin breakdown^{1,4,6,7,12,13,24,30}. The presence of a deformity increases local mechanical stresses and pressures^1,3,4,7,13. Peak plantar pressures are much higher in patients with acute Charcot arthropathy and in those with a history of neuropathic ulceration than in patients with no history of arthropathy or in patients with neuropathy but no history of ulceration³. Patients with diabetic neuropathy who have a foot deformity and a history of ulceration are at approximately thirty-six times greater risk for the development of another ulcer^4,13. Myerson et al. reported that an underlying fixed deformity or osseous prominence was associated with twenty-two (31 percent) of seventy-one neuropathic ulcers that recurred after treatment⁵². The ulcers in the midfoot resulted from neuropathic arthropathy. Although the site of maximum deformity in patients with Charcot arthropathy is the midfoot, the peak plantar pressure is in the forefoot³. Thus, treatment of Charcot arthropathy must be directed toward preventing chronic foot deformity and abnormal plantar pressure while still ensuring healing without immediate complications.

Proponents of conservative treatment cite the poor results that have been reported after attempts at operative correction. Those results were attributed to nonunions secondary to inadequate fixation, a compromised blood supply, and a high rate of infection. Even with modern techniques of fracture fixation, it has been argued that bone-softening, resorption, and fragmentation in the acute stage still make adequate fixation difficult^18,55. If a deformity created by immobilization without reduction results in complications in the midfoot, simple exostectomy can be performed^{2,11,16,48,53}. In addition, arthrodesis is a successful alternative method of limb salvage in these patients^{2,11,19,20,22,25,38,55,61,62,67,69}. However, there is no evidence that either exostectomy or late-stage arthrodesis reduces peak pressures in the forefoot, and each procedure has risks^19,62. In fact, the use of late-stage arthrodesis of the midfoot as a salvage procedure can alter the distribution of pressures under the foot and lead to plantar ulceration⁵⁵.

In the present study, all fourteen patients who underwent early arthrodesis for Eichenholtz stage-I Charcot arthropathy of the foot had anatomical reduction, clinical union, and stability without an increased risk of complications. These results do not seem related to any uniqueness of our patient population, as the ages of the patients, the type and duration of the diabetes, and the comorbidities in the present study were similar to those reported in previous clinical studies addressing this problem^{3,11,14,19,22,25,33,35,42,47,48,53,55,62,64,68}. Our patients also had patterns of joint destruction similar to those described by Sammarco and Conti⁶². The few differences that were noted were related to the earlier stage at which our subjects were treated, with Lisfranc or Chopart joints, or both, demonstrating more bone resorption but less fragmentation and milder joint diastases than typically are seen in association with Eichenholtz stage-II or stage-III arthropathy. Operating at this early stage did not seem to lengthen the healing time and in fact may have expedited the reversal of the destructive process. Whether this possible reversal is related to anatomical restoration and stabilization or to the bone-stimulating properties of autografts is not known.

Our patient-group comparisons were prompted by a lack of data in the literature related to many of the factors that we investigated. Because the numbers in each group are small, careful attention was paid to the statistical techniques that were used and to the conclusions that were drawn. Thus, confidence intervals²³ were used for the comparisons and all of the patients were followed for more than two years. We found that, despite the loss of midfoot flexibility, the patients who had been managed with early arthrodesis had an overall gait pattern and dynamic plantar pressures that were little different from those observed in the other two groups. Where comparisons can be made, our data is similar to that found in the literature. Several investigators who have examined the gait of individuals with diabetic neuropathy have noted mean free-walking speeds similar to those recorded for our patients^44,49,50. Those studies and others related to the gait of patients who have had a renal transplantation^9,10 or a below-the-knee amputation^59,70 have suggested that the gait patterns observed in all three of our groups and the reason for their similarities are most related to diabetic neuropathy as it affects peak torque during plantar flexion rather than to associated comorbidities or other demographic factors. Moreover, these findings imply that local issues related to the foot are the factors that most affect plantar pressures and the risk of ulceration. The efficacy of early arthrodesis is also suggested by the the restoration of plantar pressures to values similar to those found in our comparison group of subjects with diabetic neuropathy at approximately two years after operative intervention. It has been reported that a patient who requires amputation incurs a mean charge of $22,419 for the initial hospitalization alone²⁶; our data is consistent with this figure. Our study on the operative treatment of Charcot arthropathy suggests that the charge for an arthrodesis, previously reported as 14 percent less than the total charge for a below-the-knee amputation⁴², may be reduced even further.

While diabetes is a chronic disorder affecting multiple organ systems, medical advances in drug therapy, cardiology, ophthalmology, and transplantation procedures allow such patients to lead longer, healthier, and more functional lives. Avoidance of the lower-limb complications associated with diabetic neuropathy is of high priority, especially when a patient has had an amputation. Following an amputation, increased energy is required to walk⁷⁰. Diabetic patients who have had a unilateral lower-limb amputation have a much poorer psychosocial adjustment to illness than do diabetic patients who have not had an amputation. Moreover, suffering may be compounded by the fact that diabetic patients who have had a previous amputation are much more likely to require amputation of the contralateral limb⁵³. Also, the costs incurred and the time involved in patient care and absence from normal daily activities due to ulcers, their treatment, and complications also cannot be ignored. Given these facts and the findings of the present study, we believe that early arthrodesis should be considered for diabetic patients who have stage-I Charcot arthropathy.

Note: The authors wish to express their sincere appreciation to Alex Mason, B.S., Dr. Robert Leighty, Ph.D., and Ms. Dionne Swift, M.S.

References

Introduction | Materials and Methods | Results | Discussion | References

Armstrong, D. G.; Lavery, L. A.; and Harkless, L. B.: Treatment-based classification system for assessment and care of diabetic feet. J. Am. Podiat. Med. Assn.,86: 311-316, 1996.86311 1996

Armstrong, D. G.; Todd, W. F.; Lavery, L. A.; Harkless, L. B.; and Bushman, T. R.: The natural history of acute Charcot's arthropathy in a diabetic foot specialty clinic. Diabetic Med.,14: 357-363, 1997.14357 1997 [PubMed]

Armstrong, D. G., and Lavery, L. A.: Elevated peak plantar pressures in patients who have Charcot arthropathy. J. Bone and Joint Surg.,80-A: 365-369, March 1998.80-A365 1998

Armstrong, D. G.; Lavery, L. A.; and Harkless, L. B.: Who is at risk for diabetic foot ulceration?. Clin. Podiat. Med. and Surg.,15: 11-19, 1998.1511 1998

Armstrong, D. G.; Lavery, L. A.; Vela, S. A.; Quebedeaux, T. L.; and Fleischli, J. G.: Choosing a practical screening instrument to identify patients at risk for diabetic foot ulceration. Arch. Intern. Med.,158: 289-292, 1998.158289 1998 [PubMed]

Balkin, S. W., and Kaplan, I.: Silicone injection management of diabetic food ulcers: a possible model for prevention of pressure ulcers. Decubitus,,4: 38-40, 1991.438 1991

Bauman, J. H.; Girling, J. P.; and Brand, P. W.: Plantar pressures and trophic ulceration. An evaluation of footwear. J. Bone and Joint Surg.,45-B(4): 652-673, 1963.45-B(4)652 1963

Blanford, A. T.; Keane, S. P.; McCarty, D. J.; and Albers, J. W.: Idiopathic Charcot joint of the elbow. Arthrit. and Rheumat.,21: 723-726, 1978.21723 1978

Bohannon, R. W.; Smith, J.; Hull, D.; Palmeri, D.; and Bernhard, R.: Deficits in lower extremity muscle and gait performance among renal transplant candidates. Arch. Phys. Med. and Rehab.,76: 547-551, 1995.76547 1995

Bohannon, R. W.; Smith, J.; Hull, D.; Palmeri, D.; and Bernhard, R.: Strength, balance and gait before and after kidney transplantation. Internat. J. Rehab. Res.,20: 199-203, 1997.20199 1997

Bono, J. V.; Roger, D. J.; and Jacobs, R. L.: Surgical arthrodesis of the neuropathic foot. A salvage procedure. Clin. Orthop.,296: 14-20, 1993.29614 1993 [PubMed]

Boulton, A. J.: The diabetic foot. Med. Clin. North America,72: 1513-1530, 1988.721513 1988

Brand, P. W.: Repetitive stress in the development of diabetic foot ulcers. In The Diabetic Foot, edited by M. E. Levin and L. W. O'Neal. Ed. 4, pp. 83-90. St. Louis, C. V. Mosby, 1988.

Briggs, J. R., and Freehafer, A. A.: Fusion of the Charcot spine. Report of 3 cases. Clin. Orthop.,53: 83-93, 1967.5383 1967 [PubMed]

Brodsky, J. W., and Schneidler, C.: Diabetic foot infections. Orthop. Clin. North America,22: 473-489, 1991.22473 1991

Brodsky, J. W., and Rouse, A. M.: Exostectomy for symptomatic bony prominences in diabetic Charcot feet. Clin. Orthop.,296: 21-26, 1993.29621 1993 [PubMed]

Carrington, A. L.; Mawdsley, S. K. V.; Morley, M.; Kincey, J.; and Boulton, A. J. M.: Psychological status of diabetic people with or without lower limb disability. Diabetes Res. and Clin. Pract.,32: 19-25, 1996.3219 1996

Charcot, J.-M.: Sur quelques arthropathies qui paraissant dè¯¥ndre d'une lè²©on du cerveau ou de la moelle è¯©niç±¥. Arch. physiol. norm. pathol.,1: 161-178, 1868.1161 1868

Clohisy, D. R., and Thompson, R. C., Jr.: Fractures associated with neuropathic arthropathy in adults who have juvenile-onset diabetes. J. Bone and Joint Surg.,70-A: 1192-1200, Sept 1988.70-A1192 1988

Cohn, B. T., and Brahms, M. A.: Diabetic arthropathy of the first metatarsal cuneiform joint. Introduction of a new surgical fusion technique. Orthop. Rev.,16: 465-470, 1987.16465 1987 [PubMed]

Ctercteko, G. C.; Dhanendron, M.; Hutton, W. C.;; and Le Quesne, L. P.: Vertical forces acting on the feet of diabetic patients with neuropathic ulceration. British J. Surg.,68: 608-614, 1981.68608 1981

Deresh, G. M., and Cohen, M.: Reconstruction of the diabetic Charcot foot incorporating bone grafts. J. Foot and Ankle Surg.,35: 474-488, 1996.35474 1996

Dorey, F.; Nasser, S.; and Amstutz, H.: Current concepts review. The need for confidence intervals in the presentation of orthopaedic data. J. Bone and Joint Surg.,75-A: 1844-1852, Dec 1993.75-A1844 1993

Duffy, J. C., and Patout, C. A., Jr.: Management of the insensitive foot in diabetes: lessons learned from Hansen's disease. Milit. Med.,155: 575-579, 1990.155575 1990

Early, J. S., and Hansen, S. T.: Surgical reconstruction of the diabetic foot: a salvage approach for midfoot collapse. Foot and Ankle Internat.,17: 325-330, 1996.17325 1996

Eckman, M. H.; Greenfield, S.; Mackey, W. C.; Wong, J. B.; Kaplan, S.; Sullivan, L.; Dukes, K.; and Pauker, S. G.: Foot infections in diabetic patients. Decision and cost-effective analyses. J. Am. Med. Assn.,273: 712-720, 1995.273712 1995

Edelman, S. V.; Kosofsky, E. M.; Paul, R. A.; and Kozak, G. P.: Neuro-osteoarthropathy (Charcot's joint) in diabetes mellitus following revascularization surgery. Three case reports and a review of the literature. Arch. Intern. Med.,147: 1504-1508, 1987.1471504 1987 [PubMed]

Edmonds, M. E.; Roberts, V. C.; and Watkins, P. J.: Blood flow in the diabetic neuropathic foot. Diabetologia,22: 9-15, 1982.229 1982 [PubMed]

Edmonds, M. E.; Clarke, M. B.; Newton, S.; Barrett, J.; and Watkins, P. J.: Increased uptake of bone radiopharmaceutical in diabetic neuropathy. Quart. J. Med.,57: 843-855, 1985.57843 1985 [PubMed]

Edmonds, M. E.; Blundell, M. P.; Morris, M. E.; Thomas, E. M.; Cotton, L. T.; and Watkins, P. J.: Improved survival of the diabetic foot: the role of a specialized foot clinic. Quart. J. Med.,60: 763-771, 1986.60763 1986 [PubMed]

Eichenholtz, S. N.: Charcot Joints, pp. 7-8. Springfield, Illinois, Charles C Thomas, 1966.

Feldman, M. J.; Becker, K. L.; Reefe, W. E.;, and Longo, A.: Multiple neuropathic joints, including the wrist, in a patient with diabetes mellitus. J. Am. Med. Assn.,,209: 1690-1692, 1969.2091690 1969

Fryberg, R. G., and Kozak, G. P.: Neuropathic arthropathy in the diabetic foot. Am. Fam. Physician,17: 105-113, 1978.17105 1978 [PubMed]

Fullerton, B. D., and Browngoehl, L. A.: Total knee arthroplasty in a patient with bilateral Charcot knees. Arch. Phys. Med. and Rehab.,78: 780-782, 1997.78780 1997

Giurini, J. M., and Rosenblum, B. I.: The role of foot surgery in patients with diabetes. Clin. Podiat. Med. and Surg.,12: 119-127, 1995.12119 1995

Gough, A.; Abraha, H.; Li, F.; Purewal, T. S.; Foster, A. V.; Watkins, P. J.; Moniz, C.; and Edmonds, M. E.: Measurement of markers of osteoclast and osteoblast activity in patients with acute and chronic diabetic Charcot neuroarthropathy. Diabetic Med.,,14: 527-531, 1997.14527 1997

Graf, P. M.: The EMED system of foot pressure analysis. Clin. Podiat. Med. and Surg.,10: 445-454, 1993.10445 1993

Heiple, K. G., and Cammarn, M. R.: Diabetic neuroarthropathy with spontaneous peritalar fracture-dislocation. A report of two cases. J. Bone and Joint Surg.,48-A: 1177-1181, Sept 1966.48-A1177 1966

Hochberg, Y., and Tamhane, A. C.: Multiple Comparison Procedures. New York, Wiley, 1987.

Holewski, J. J.; Moss, K. M.; Stess, R. M.; Graf, P. M.; and Grunfeld, C.: Prevalence of foot pathology and lower extremity complications in a diabetic outpatient clinic. J. Rehab. Res. and Devel.,26: 35-44, 1989.2635 1989

Hollander, M., and Wolfe, D. A.: Nonparametric Statistical Methods. New York, Wiley, 1973.

Johnson, J. E.; O'Brien, T. S.; Hart, T. S.; Mitchell, J. R.; Den Hartog, B.; and Gould, J. S.: Reconstruction of the Charcot foot and ankle: an outcome study of long term-results. Read at the Annual Meeting of the American Orthopaedic Foot and Ankle Society, Hilton Head, South Carolina, June 30, 1996.

Jordan, W. R.: Neuritic manifestations in diabetes mellitus. Arch. Intern. Med.,57: 307-366, 1936.57307 1936

Katoulis, E. C.; Ebdon-Parry, M.; Lanshammar, H.; Vileikyte, L.; Kulkarni, J.; and Boulton, A. J.: Gait abnormalities in diabetic neuropathy. Diabetes Care,20: 1904-1907, 1997.201904 1997 [PubMed]

Kramers de Quervain, I. A.; Simon, S. R.; Leurgans, S.; Pease, W. S.; and McAllister, D.: Gait pattern in the early recovery period after stroke. J. Bone and Joint Surg.,78-A: 1506-1514, Oct 1996.78-A1506 1996

Lehmann, E. L.: Nonparametrics: Statistical Methods Based on Ranks. San Francisco, Holden-Day, 1975.

Lesko, P., and Maurer, R. C.: Talonavicular dislocations and midfoot arthropathy in neuropathic diabetic feet. Natural course and principles of treatment. Clin. Orthop.,240: 226-231, 1989.240226 1989 [PubMed]

Leventeen, E. O.: Charcot foot ä?¡ technique for treatment of chronic plantar ulcer by saucerization and primary closure. Foot and Ankle,6: 295-299, 1986.6295 1986 [PubMed]

Mueller, M. J.; Minor, S. D.; Sahrmann, S. A.; Schaaf, J. A.; and Strube, M. J.: Differences in the gait characteristics of patients with diabetes and peripheral neuropathy compared with age-matched controls. Phys. Ther.,74: 299-313, 1994.74299 1994 [PubMed]

Mueller, M. J.; Minor, S. D.; Schaaf, J. A.; Strube, M. J.; and Sahrmann, S. A.: Relationship of plantar-flexor peak torque and dorsiflexion range of motion to kinetic variables during walking. Phys. Ther.,,75: 684-693, 1995.75684 1995

Mueller, M. J.: Identifying patients with diabetes mellitus who are at risk for lower-extremity complications: use of Semmes-Weinstein monofilaments. Phys. Ther.,76: 68-71, 1996.7668 1996 [PubMed]

Myerson, M.; Papa, J.; Eaton, K.; and Wilson, K.: The total-contact cast for management of neuropathic plantar ulceration of the foot. J. Bone and Joint Surg.,74-A: 261-269, Feb 1992.74-A261 1992

Myerson, M. S.; Henderson, M. R.; Saxby, T.; and Short, K. W.: Management of midfoot diabetic neuroarthropathy. Foot and Ankle Internat.,15: 233-241, 1994.15233 1994

National Diabetes Information Clearinghouse: Diabetes Statistics. National Institutes of Health Publication 96-3926. Bethesda, Maryland, United States Department of Health and Human Services, Government Printing Office, June 18, 1997.

Papa, J.; Myerson, M.; and Girard, P.: Salvage, with arthrodesis, in intractable diabetic neuropathic arthropathy of the foot and ankle. J. Bone and Joint Surg.,75-A: 1056-1066, July 1993.75-A1056 1993

Pedersen, L. M.; Madsen, O. R.; and Bliddal, H.: Charcot arthropathy as an unusual initial manifestation of diabetes mellitus [letter]. British J. Rheumatol.,32: 854-855, 1993.32854 1993

Purewal, T. S.; Goss, D. E.; Watkins, P. J.; and Edmonds, M. E.: Lower limb venous pressure in diabetic neuropathy. Diabetes Care,18: 377-381, 1995.18377 1995 [PubMed]

Raju, U. B.; Fine, G.; and Partamian, J. O.: Diabetic neuroarthropathy (Charcot's joint). Arch. Pathol. and Lab. Med.,106: 349-351, 1982.106349 1982

Robinson, J. L.; Smidt, G. L.;; and Arora, J. S.: Accelographic, temporal, and distance gait: factors in below-knee amputees. Phys. Ther.,57: 898-904, 1977.57898 1977 [PubMed]

Rochon, P. A.; Katz, J. N.; Morrow, L. A.; McGlinchey-Berroth, R.; Ahlquist, M. M.; Sarkarati, M.; and Minaker, K. L.: Comorbid illness is associated with survival and length of hospital stay in patients with chronic disability. A prospective comparison of three comorbidity indices. Med. Care,34: 1093-1101, 1996.341093 1996 [PubMed]

Samilson, R. L.; Sankaran, B.; Bersani, F. A.; and Smith, A. D.: Orthopedic management of neuropathic joints. Arch. Surg.,78: 115-121, 1959.78115 1959

Sammarco, G. J., and Conti, S. F.: Surgical treatment of neuroarthropathic foot deformity. Foot and Ankle Internat.,19: 102-109, 1998.19102 1998

Shaw, J. E., and Boulton, A. J.: The pathogenesis of diabetic foot problems: an overview. Diabetes,46 (Supplement 2): 58-S61, 1997.46 (Supplement 2)58 1997

Sinha, S.; Munichoodappa, C. S.; and Kozak, G. P.: Neuro-arthropathy (Charcot joints) in diabetes mellitus. Medicine,51: 191-210, 1972.51191 1972 [PubMed]

Sprenger, T. R., and Foley, C. J.: Hip replacement in a Charcot joint. A case report and historical review. Clin. Orthop.,165: 191-194, 1982.165191 1982 [PubMed]

Stess, R. M.; Jensen, S. R.; and Mirmiran, R.: The role of dynamic plantar pressures in diabetic foot ulcers. Diabetes Care,20: 855-858, 1997.20855 1997 [PubMed]

Stuart, M. J., and Morrey, B. F.: Arthrodesis of the diabetic neuropathic ankle joint. Clin. Orthop.,253: 209-211, 1990.253209 1990 [PubMed]

Tisdel, C. L.; Marcus, R. E.; and Heiple, K. G.: Triple arthrodesis for diabetic peritalar neuroarthropathy. Foot and Ankle Internat.,16: 332-338, 1995.16332 1995

Veves, A.; Murray, H. J.; Young, M. J.; and Boulton, A. J.: The risk of foot ulceration in diabetic patients with high foot pressure: a prospective study. Diabetologia,35: 660-663, 1992.35660 1992 [PubMed]

Waters, R. L.; Perry, J.; Antonelli, D.; and Hislop, H.: Energy cost of walking of amputees: the influence of level of amputation. J. Bone and Joint Surg.,58-A: 42-46, Jan 1976.58-A42 1976

Watkins, P. J., and Edmonds, M. E.: Sympathetic nerve failure in diabetes. Diabetologia,25: 73-77, 1983.2573 1983 [PubMed]

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Fig. 2:: Map of the right foot of a typical subject, showing the eleven mask regions (M) used in the measurement and analysis of plantar pressures.

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Fig. 3-B::

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Fig. 3-C::

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Table I: Demographic and Gait Data

	Group
Arthrodesis	Amputation	Diabetic- Neuropathy*
Demographic data
Gender (male/female) (no. of patients)	10/4	11/3	6/8
Diabetes (type I/type II) (no. of patients)	12/2	4/10	9/5
Involved side (right/left) (no. of patients)	8/6	6/8	NA
Cumulative Illness Rating Scale score†⁶⁰(points)	10.5 ±4.3 (2.0-14.0)	11.8 ±6.1 (4.0-20.0)	8.0 ±3.8 (2.0-11.0)
Age at op.† (yrs.)	48.2 ±9.5 (32.1-60.4)	56.5 ±13.0 (40.2-80.7)	NA
Duration of diabetes at op.†(yrs.)	22.1 ±9.0 (3.0-39.0)	20.8 ±8.4 (2.0-38.0)	NA
Age at testing†(yrs.)	50.7 ±8.8 (35.8-61.4)	58.8 ±12.5 (40.5-81.3)	52.1 ±11.3 (31.3-65.5)
Weight at testing† (kg)	88.4 ±22.8 (59.1-140.0)	88.9 ±20.2 (61.1-129.6)	88.8 ±20.2 (52.3-134.8)
Duration of diabetes at testing (yrs.)	24.6 ±9.2 (5.0-40.0)	23.1 ±10.2 (3.0-47.0)	21.1 ±11.1 (4.0-38.0)
Gait data
Cadence (steps/min.)	97.2 ±14.4	84.0 ±18.0	99.6 ±13.2
Stride length (m)	1.15 ±0.27	0.998 ±0.36	1.04 ±0.18
Velocity (m/sec.)	0.95 ±0.31	0.74 ±0.32	0.87 ±0.22
Pelvis (degrees)
Total range of motion	3.6 ±1.5	4.3 ±1.6	4.1 ±1.8
Maximum flexion	10.5 ±3.6	9.6 ±6.9	9.8 ±8.9
Maximum extension	-6.9 ±3.9	-5.5 ±6.7	-5.8 ±8.6
Hip (degrees)
Total range of motion	39.4 ±7.5	39.2 ±10.3	38.5 ±5.1
Maximum flexion	35.9 ±10.2	40.3 ±7.2	34.7 ±9.7
Maximum extension	3.6 ±6.6	-1.2 ±12.4	3.8 ±12.0
Knee (degrees)
Total range of motion	56.1 ±10.1	55.0 ±10.5	53.4 ±8.0
Maximum flexion	58.5 ±13.6	63.5 ±10.0	57.2 ±10.1
Maximum extension	-2.4 ±6.0	-8.5 ±7.4	-3.8 ±6.6
Ankle (degrees)
Total range of motion	18.4 ±5.6	14.5 ±6.9	20.3 ±4.4
Maximum dorsiflexion	13.4 ±4.4	13.8 ±5.7	13.6 ±5.6
Maximum plantar flexion	-2.7 ±8.0	-0.7 ±3.9	-6.3 ±5.8

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Table I: Demographic and Gait Data

	Group
Arthrodesis	Amputation	Diabetic- Neuropathy*
Demographic data
Gender (male/female) (no. of patients)	10/4	11/3	6/8
Diabetes (type I/type II) (no. of patients)	12/2	4/10	9/5
Involved side (right/left) (no. of patients)	8/6	6/8	NA
Cumulative Illness Rating Scale score†⁶⁰(points)	10.5 ±4.3 (2.0-14.0)	11.8 ±6.1 (4.0-20.0)	8.0 ±3.8 (2.0-11.0)
Age at op.† (yrs.)	48.2 ±9.5 (32.1-60.4)	56.5 ±13.0 (40.2-80.7)	NA
Duration of diabetes at op.†(yrs.)	22.1 ±9.0 (3.0-39.0)	20.8 ±8.4 (2.0-38.0)	NA
Age at testing†(yrs.)	50.7 ±8.8 (35.8-61.4)	58.8 ±12.5 (40.5-81.3)	52.1 ±11.3 (31.3-65.5)
Weight at testing† (kg)	88.4 ±22.8 (59.1-140.0)	88.9 ±20.2 (61.1-129.6)	88.8 ±20.2 (52.3-134.8)
Duration of diabetes at testing (yrs.)	24.6 ±9.2 (5.0-40.0)	23.1 ±10.2 (3.0-47.0)	21.1 ±11.1 (4.0-38.0)
Gait data
Cadence (steps/min.)	97.2 ±14.4	84.0 ±18.0	99.6 ±13.2
Stride length (m)	1.15 ±0.27	0.998 ±0.36	1.04 ±0.18
Velocity (m/sec.)	0.95 ±0.31	0.74 ±0.32	0.87 ±0.22
Pelvis (degrees)
Total range of motion	3.6 ±1.5	4.3 ±1.6	4.1 ±1.8
Maximum flexion	10.5 ±3.6	9.6 ±6.9	9.8 ±8.9
Maximum extension	-6.9 ±3.9	-5.5 ±6.7	-5.8 ±8.6
Hip (degrees)
Total range of motion	39.4 ±7.5	39.2 ±10.3	38.5 ±5.1
Maximum flexion	35.9 ±10.2	40.3 ±7.2	34.7 ±9.7
Maximum extension	3.6 ±6.6	-1.2 ±12.4	3.8 ±12.0
Knee (degrees)
Total range of motion	56.1 ±10.1	55.0 ±10.5	53.4 ±8.0
Maximum flexion	58.5 ±13.6	63.5 ±10.0	57.2 ±10.1
Maximum extension	-2.4 ±6.0	-8.5 ±7.4	-3.8 ±6.6
Ankle (degrees)
Total range of motion	18.4 ±5.6	14.5 ±6.9	20.3 ±4.4
Maximum dorsiflexion	13.4 ±4.4	13.8 ±5.7	13.6 ±5.6
Maximum plantar flexion	-2.7 ±8.0	-0.7 ±3.9	-6.3 ±5.8

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Table II: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for the Group Differences in Cadence, Stride Length, and Velocity

*More than three comparisons in each column.

Groups Compared	Cadence (steps/min.)	Stride Length (m)	Velocity (m/sec.)
Arthrodesis (affected side) and diabetic neuropathy (left side)	-25.92, 0.36	-0.305, 0.239	-0.347, 0.148
Amputation (affected side) and diabetic neuropathy (left side)	-15.72, 12.12	-0.093, 0.382	-0.198, 0.359
Amputation (affected side) and arthrodesis (affected side)	-27.12, 1.44	-0.411, 0.154	-0.539, 0.130

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Table II: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for the Group Differences in Cadence, Stride Length, and Velocity

*More than three comparisons in each column.

Groups Compared	Cadence (steps/min.)	Stride Length (m)	Velocity (m/sec.)
Arthrodesis (affected side) and diabetic neuropathy (left side)	-25.92, 0.36	-0.305, 0.239	-0.347, 0.148
Amputation (affected side) and diabetic neuropathy (left side)	-15.72, 12.12	-0.093, 0.382	-0.198, 0.359
Amputation (affected side) and arthrodesis (affected side)	-27.12, 1.44	-0.411, 0.154	-0.539, 0.130

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Table III: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for the Group Differences in,Maximum Minimum, and Total Joint Angles

*More than eight comparisons in each column.

Groups Compared	Maximum Angle (degrees)			Minimum Angle (degrees)			Total Range of Motion (degrees)
Hip	Knee	Ankle	Hip	Knee	Ankle	Hip	Knee	Ankle
Arthrodesis (affected side) and diabetic neuropathy (left side)	-10.83, 13.49	-8.55, 11.16	-5.80, 6.20	-9.79, 11.70	-9.314, 6.647	-2.78, 8.80	-5.09, 8.48	-6.91, 11.51	-7.22, 3.55
Arthrodesis (unaffected side) and diabetic neuropathy (left side)	-8.45, 15.40	-2.72, 13.83	-4.10, 10.91	-7.82, 12.46	-7.08, 11.03	-4.481, 8.17	-7.45, 9.30	-7.21, 13.16	-3.94, 5.39
Amputation (affected side) and diabetic neuropathy (left side)	-5.14,16.91	-5.55, 16.84	-6.47, 6.83	-9.99, 19.72	-4.24, 13.92	-0.225, 11.65	-7.63, 10.85	-9.64, 9.98	-13.18, 1.58
Amputation (unaffected side) and diabetic neuropathy (left side)	-6.49, 17.06	-4.92, 15.12	-2.88, 9.07	-12.36, 19.49	-3.243, 13.85	-5.259, 7.60	-5.98, 7.55	-8.32, 9.09	-3.98, 7.71
Amputation (affected side) and arthrodesis (affected side)	-5.14, 12.14	-7.19, 16.52	-5.58, 4.90	-8.54, 17.71	-2.470, 14.88	-1.994, 8.36	-10.45, 9.57	-12.55, 9.69	-11.45, 3.82
Amputation (affected side) and arthrodesis (unaffected side)	-7.25, 11.01	-10.29, 10.68	-9.56, 3.58	-8.69, 16.76	-6.44, 12.49	-1.366, 9.49	-10.91, 11.43	-13.35, 9.52	-13.69, 0.64
Amputation (unaffected side) and arthrodesis (affected side)	-7.18, 12.00	-6.95, 14.82	-2.43, 7.02	-10.59, 16.63	-0.965, 14.27	-6.249, 2.58	-8.59, 6.98	-11.21, 7.88	-2.45, 8.39
Amputation (unaffected side) and arthrodesis (unaffected side)	-8.71, 10.36	-9.64, 9.80	-5.89, 5.73	-10.79, 15.74	-5.31, 12.34	-5.60, 4.24	-9.23, 9.37	-13.63, 7.76	-4.73, 5.79

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Table III: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for the Group Differences in,Maximum Minimum, and Total Joint Angles

*More than eight comparisons in each column.

Groups Compared	Maximum Angle (degrees)			Minimum Angle (degrees)			Total Range of Motion (degrees)
Hip	Knee	Ankle	Hip	Knee	Ankle	Hip	Knee	Ankle
Arthrodesis (affected side) and diabetic neuropathy (left side)	-10.83, 13.49	-8.55, 11.16	-5.80, 6.20	-9.79, 11.70	-9.314, 6.647	-2.78, 8.80	-5.09, 8.48	-6.91, 11.51	-7.22, 3.55
Arthrodesis (unaffected side) and diabetic neuropathy (left side)	-8.45, 15.40	-2.72, 13.83	-4.10, 10.91	-7.82, 12.46	-7.08, 11.03	-4.481, 8.17	-7.45, 9.30	-7.21, 13.16	-3.94, 5.39
Amputation (affected side) and diabetic neuropathy (left side)	-5.14,16.91	-5.55, 16.84	-6.47, 6.83	-9.99, 19.72	-4.24, 13.92	-0.225, 11.65	-7.63, 10.85	-9.64, 9.98	-13.18, 1.58
Amputation (unaffected side) and diabetic neuropathy (left side)	-6.49, 17.06	-4.92, 15.12	-2.88, 9.07	-12.36, 19.49	-3.243, 13.85	-5.259, 7.60	-5.98, 7.55	-8.32, 9.09	-3.98, 7.71
Amputation (affected side) and arthrodesis (affected side)	-5.14, 12.14	-7.19, 16.52	-5.58, 4.90	-8.54, 17.71	-2.470, 14.88	-1.994, 8.36	-10.45, 9.57	-12.55, 9.69	-11.45, 3.82
Amputation (affected side) and arthrodesis (unaffected side)	-7.25, 11.01	-10.29, 10.68	-9.56, 3.58	-8.69, 16.76	-6.44, 12.49	-1.366, 9.49	-10.91, 11.43	-13.35, 9.52	-13.69, 0.64
Amputation (unaffected side) and arthrodesis (affected side)	-7.18, 12.00	-6.95, 14.82	-2.43, 7.02	-10.59, 16.63	-0.965, 14.27	-6.249, 2.58	-8.59, 6.98	-11.21, 7.88	-2.45, 8.39
Amputation (unaffected side) and arthrodesis (unaffected side)	-8.71, 10.36	-9.64, 9.80	-5.89, 5.73	-10.79, 15.74	-5.31, 12.34	-5.60, 4.24	-9.23, 9.37	-13.63, 7.76	-4.73, 5.79

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Table IV: Peak Plantar Foot Pressures in the Eleven Mask Regions of the Foot

*The values are expressed as the mean and the standard deviation.†The values are expressed as the mean.

Region	Amputation (Unaffected Side)* (N = 12)	Arthrodesis (Unaffected Side)* (N = 13)	Arthrodesis (Affected Side)* (N = 13)	Diabetic Neuropathy (Composite)† (N = 14)
Heel (Mask 1)	19.25 ±5.90	23.83 ±7.46	18.18 ±5.42	18.79
Midfoot
Medial aspect (Mask 11)	12.20 ±6.37	8.29 ±3.28	10.67 ±3.19	8.29
Lateral aspect (Mask 10)	12.22 ±5.41	10.03 ±4.33	13.00 ±6.62	10.90
Metatarsals
First (Mask 2)	26.42 ±15.6	23.08 ±8.51	25.10 ±14.9	23.38
Second (Mask 3)	18.75 ±5.55	18.95 ±6.57	15.97 ±6.35	20.98
Third (Mask 4)	18.11 ±8.60	17.13 ±7.14	14.68 ±8.76	19.41
Fourth (Mask 5)	16.06 ±8.63	14.18 ±5.66	12.69 ±7.26	16.10
Fifth (Mask 6)	10.78 ±5.49	10.04 ±4.88	11.83 ±8.68	12.59
Toes
Great (Mask 7)	21.22 ±15.3	20.06 ±10.7	14.87 ±10.5	11.29
Second (Mask 8)	12.78 ±7.58	12.93 ±5.29	9.17 ±6.02	11.12
Third (Mask 9)	9.39 ±4.07	10.22 ±5.28	6.00 ±4.76	10.29

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Table IV: Peak Plantar Foot Pressures in the Eleven Mask Regions of the Foot

*The values are expressed as the mean and the standard deviation.†The values are expressed as the mean.

Region	Amputation (Unaffected Side)* (N = 12)	Arthrodesis (Unaffected Side)* (N = 13)	Arthrodesis (Affected Side)* (N = 13)	Diabetic Neuropathy (Composite)† (N = 14)
Heel (Mask 1)	19.25 ±5.90	23.83 ±7.46	18.18 ±5.42	18.79
Midfoot
Medial aspect (Mask 11)	12.20 ±6.37	8.29 ±3.28	10.67 ±3.19	8.29
Lateral aspect (Mask 10)	12.22 ±5.41	10.03 ±4.33	13.00 ±6.62	10.90
Metatarsals
First (Mask 2)	26.42 ±15.6	23.08 ±8.51	25.10 ±14.9	23.38
Second (Mask 3)	18.75 ±5.55	18.95 ±6.57	15.97 ±6.35	20.98
Third (Mask 4)	18.11 ±8.60	17.13 ±7.14	14.68 ±8.76	19.41
Fourth (Mask 5)	16.06 ±8.63	14.18 ±5.66	12.69 ±7.26	16.10
Fifth (Mask 6)	10.78 ±5.49	10.04 ±4.88	11.83 ±8.68	12.59
Toes
Great (Mask 7)	21.22 ±15.3	20.06 ±10.7	14.87 ±10.5	11.29
Second (Mask 8)	12.78 ±7.58	12.93 ±5.29	9.17 ±6.02	11.12
Third (Mask 9)	9.39 ±4.07	10.22 ±5.28	6.00 ±4.76	10.29

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Table V: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for Peak Plantar Pressure in Six Mask Regions of the Foot

*More than five comparisons in each column.

Groups Compared	First Metatarsal (Mask 2)	Third Metatarsal (Mask 4)	Fifth Metatarsal (Mask 6)	Great Toe (Mask 7)	Lateral Aspect of Midfoot (Mask 10)	Medial Aspect of Midfoot (Mask 11)
Arthrodesis (affected side) and diabetic neuropathy (left side)	-11.00, 16.00	-16.00, 0.00	-9.00, 5.99	-8.00, 13.00	-6.00, 5.99	-2.00, 5.99
Arthrodesis (unaffected side) and diabetic neuropathy (left side)	-6.00, 13.00	-14.00, 5.00	-10.00, 0.00	-1.00, 23.00	-9.00, 3.00	-5.00, 4.00
Amputation (unaffected side) and diabetic neuropathy (left side)	-9.01, 11.99	-14.00, 4.00	-10.00, 1.00	-1.00, 21.00	-6.00, 6.00	-2.00, 9.00
Amputation (unaffected side) and arthrodesis (affected side)	-18.01, 15.99	-6.01, 10.00	-12.00, 4.00	-7.01, 20.01	-6.00, 7.00	-3.99, 8.00
Amputation (unaffected side) and arthrodesis (unaffected side)	-14.00, 11.00	-11.00, 9.00	-3.99, 4.00	-14.99, 13.00	-3.00, 10.00	-0.99, 10.00

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Table V: Ninety-five Percent Simultaneous* Hodges-Lehmann Confidence Intervals for Peak Plantar Pressure in Six Mask Regions of the Foot

*More than five comparisons in each column.

Groups Compared	First Metatarsal (Mask 2)	Third Metatarsal (Mask 4)	Fifth Metatarsal (Mask 6)	Great Toe (Mask 7)	Lateral Aspect of Midfoot (Mask 10)	Medial Aspect of Midfoot (Mask 11)
Arthrodesis (affected side) and diabetic neuropathy (left side)	-11.00, 16.00	-16.00, 0.00	-9.00, 5.99	-8.00, 13.00	-6.00, 5.99	-2.00, 5.99
Arthrodesis (unaffected side) and diabetic neuropathy (left side)	-6.00, 13.00	-14.00, 5.00	-10.00, 0.00	-1.00, 23.00	-9.00, 3.00	-5.00, 4.00
Amputation (unaffected side) and diabetic neuropathy (left side)	-9.01, 11.99	-14.00, 4.00	-10.00, 1.00	-1.00, 21.00	-6.00, 6.00	-2.00, 9.00
Amputation (unaffected side) and arthrodesis (affected side)	-18.01, 15.99	-6.01, 10.00	-12.00, 4.00	-7.01, 20.01	-6.00, 7.00	-3.99, 8.00
Amputation (unaffected side) and arthrodesis (unaffected side)	-14.00, 11.00	-11.00, 9.00	-3.99, 4.00	-14.99, 13.00	-3.00, 10.00	-0.99, 10.00