To the Editor:

I appreciate the kind comments of Dr. Mason about our work, and I wish to both clarify and respond to his objections regarding the conclusion of our long-term study as well as to his questions about our system of data collection.

Our review of the literature of the past twenty years showed that the majority of authors have analyzed their results of ligament reconstruction, with or without tendon interposition, to treat osteoarthritis of the basal joint of the thumb on the basis of different assessment criteria. We therefore selected a standardized and well- established scoring system (1) to facilitate the comparisons with results of previous studies on surgical procedures for the treatment of osteoarthritis which have included the same assessment criteria, (2) to provide a quantitative measure that facilitates the comparisons between our patient groups, and (3) to facilitate the reproducibility of research data. The measurement instrument as described by Buck-Gramcko in 1994 is a standardized scoring system which is currently available to evaluate the overall operative outcome of surgical options for the treatment of the osteoarthritic trapeziometacarpal joint by producing a sum of points that can be easily rated as an excellent, good, fair, or poor surgical outcome. I admit that the Buck-Gramcko score has its limitations concerning the question about the daily function and the determination of the tip-pinch strength to the contralateral side. These shortcomings, however, were offset in our study by additionally analyzing the functional performance of ten tasks of daily living, by determining the postoperative employment status and activity levels, and by measuring the preoperative and postoperative tip-pinch strength values in our patients. Overall, however, the Buck-Gramcko score is an established scoring system with a high degree of patient-orientation which is well-balanced in its approach to collect and assess a considerable number of objective and subjective data.

According to the guidelines of the original Buck-Gramcko method of assessment, the overall operative outcome is solely evaluated on the basis of the grade of the total score. The grade of the total score and the mean total score are two different categories which were analyzed separately in our study. Our results of the grade of the total score, as you can see in Table IV of our article, did not differ significantly after ligament reconstruction and after the same procedure combined with tendon interposition.

The calculation of the mean total score, however, is not an integral part of the original Buck-Gramcko scoring system. In spite of this fact, we additionally did this analysis with the purpose to compare our result after ligament reconstruction with the outcome which was published by Mentzel et al.1 who calculated the mean total score as well. It is interesting, however, that this analysis resulted in a significant difference (51.3 points after ligament reconstruction versus 44.6 points after additional tendon interposition) between our two groups with the numbers of patients available. Yet, in evaluating this analysis, it is imperative to keep in mind that only a small number of patients were included in each treatment group and based on this relatively limited statistical power, we did not want to jump to conclusions.

Despite the significant differences which with the numbers available were observed between our groups in some categories, this did not have an apparent effect on our results concerning the grade of the total score which, according to the original Buck-Gramcko method of evaluation, in fact assessed the surgical outcomes after ligament reconstruction and the same procedure with tendon interposition. In consideration of our assessment together with the fact that we noted no further significant diffferences between the two groups with regard to the additional measurements (presented in Table III and in Figure 3 of our article), we have drawn the conclusion that tendon interposition does not affect the long-term objective and subjective outcomes of ligament reconstruction for treatment of advanced osteoarthritis of the thumb carpometacarpal joint.

Reference:

1. Mentzel M, Ebinger T, Heckmann E, Merk SE, Kinzl L, Wachter NJ. [Results of basal joint arthrosis treatment-comparison of Epping ligament reconstruction with trapeziectomy alone]. Handchir Mikrochir Plast Chir. 2001;33:176- 80.German.

To the Editor:

Kriegs-Au et al. are to be congratulated for publishing one of the few well-designed prospective randomised trial on this topic. However, I would like to point out that their data do not support their conclusion that tendon interposition does not affect the long-term objective and subjective outcomes of ligament reconstruction for treatment of advanced osteoarthritis of the thumb metacarpophalangeal joint.

They clearly demonstrate a significant difference in the Buck-Gramcko scores between the two groups. This is accounted for by increased thumb mobility, better cosmetic appearance and greater willingness to undergo surgery again found in the patients who had ligament reconstruction only. The other components of the Buck-Gramcko score (pain, subjective strength, function, dexterity, overall assessment of the surgical outcome and tip pinch strength) were not significantly different between the two groups.

I would consider these latter indices much more important in assessing the outcome of surgery for trapeziometacarpal osteoarthritis. Did the authors agree with this and therefore disregarded the overall Buck -Gramcko score in drawing their conclusion? If so, then this scoring system would appear to be an inappropriate method of assessing the outcome of these procedures.

Will Mason

To the Editor:

We are pleased that our article, comparing the long-term outcomes of trapezial excision with ligament reconstruction and the same procedure combined with tendon interposition, has raised the interest of Drs. Kuschner and Dr. Lane.

We believe the technique of ligament reconstruction creates a strong stabilizing ligament which suspends the first metacarpal. It effectively minimizes metacarpal subsidence caused by the loss of bony support after trapezial excision, keeps the opposing articular surfaces apart, and prevents subluxation, thereby providing stability to the basal joint of the thumb.

The strip of the tendon used in the Epping-Noack technique to establish the ligamentous suspension is firmly blocked within the canal in the first metacarpal base with trapezial fragments to counteract the tendency of proximal migration. We agree that some proximal metacarpal migration occurs even after trapeziectomy coupled with ligament reconstruction. It is of interest, however, that, after a considerable percentage loss of the arthroplasty space noted in both our patient groups during the first postoperative year, the proximal migration of the thumb metacarpal was less progressive by the four-year follow-up assessment.

The observation that progressive metacarpal subsidence documented during the early postoperative period diminished over time and the excellent patient outcomes achieved on the Buck-Gramcko score suggest that ligament reconstruction has contributed to the suspension of the first metacarpal base, the preservation of the arthroplasty space, and the stability to the first carpometacarpal joint in an optimal way.

The authors of previous reports on trapeziectomy without ligament reconstruction demonstrated preservation of an arthroplasty space in their patients at a mean of one year postoperatively as well (1-3). The short-term results suggest that vascular ingrowth may fill the trapezial void to form a fibrous tissue spacer. The literature, however, currently lacks the answer to the question of how fibrous tissue behaves within the trapezial void in the long term. It might act as an autologous gliding layer between the first metacarpal and the scaphoid which might protect the articular surfaces against attritional changes and abutment over time.

According to our statistical analyses, the height of the arthroplasty space does not seem to be a decisive factor in postoperative pain, thumb strength or function after ligament reconstruction. Despite this statistical conclusion, which is of course limited by the small number of patients enrolled in our study, we think it is of utmost importance to preserve an arthroplasty space once the diseased trapezium has been excised and to prevent bony contact between the articular surfaces. The scenario of progressive metacarpal subsidence and instability of the trapeziometacarpal joint after trapeziectomy alone might be abutment and/or subluxation over time. The long-term consequences for the patient, we fear, might be severe pain and serious functional impairment. At present, due to the lack of long-term results on simple trapeziectomy, we favor the procedure of ligament reconstruction, but we welcome additional randomized long-term studies recruiting large numbers of patients and applying methodological criteria similar to those used in our recent paper to determine the effectiveness of trapeziectomy alone on the surgical outcome. We do agree that a technically easier procedure is to be preferred over other more complex surgical options if its benefits can be clearly supported by reliable and reproducible long-term data.

Gabriele Kriegs-Au, MD, Gert Petje, MD, Eva Fojtl, MD, Rudolf Ganger, MD, and Ingrid Zachs, MD.

Corresponding author: Gabriele Kriegs-Au, MD, City Medical Center, Bauernmarkt 1/16, A-1010 Vienna, Austria; E-Mail address: sandra.brezina@gmx.at

References

1. Belcher HJ, Nicholl JE. A comparison of trapeziectomy with and without ligament reconstruction and tendon interposition. J Hand Surg [Br]. 2000;25:350-6.

2. Downing ND, Davis TR. Trapezial space height after trapeziectomy: meachnism of formation and benefits. J Hand Surg [Am]. 2001;26:862-8.

3. Davis TR, Brady O, Barton NJ, Lunn PG, Burke FD. Trapeziectomy alone, with tendon interposition or with ligament reconstruction? J Hand Surg [Br]. 1997;22:689-94.

To the Editor:

Kriegs-Au et al., in their article entitled “Ligament Reconstruction with or without Tendon Interposition to Treat Primary Thumb Carpometacarpal Osteoarthritis,” (2004;86:209-218) concluded that the degree of proximal migration of the thumb metacarpal may have no effect on postoperative thumb strength, function, and pain. At final follow-up, there was proximal migration of the thumb metacarpal compared to both the preoperative visit and the initial postoperative visit. Since this does not appear to affect ultimate outcome, we would be interested in learning the author’s opinion regarding the role and utility of ligament reconstruction. Why not trapezial resection alone (without ligament reconstruction or tendon interposition)?

Stuart H. Kuschner, M.D. 9001 Wilshire Boulevard Suite 200 Beverly Hills, California 90211 email: shkuschner@yahoo.com

Charles S. Lane, M.D. 9001 Wilshire Boulevard Suite 200 Beverly Hills, California 90211