The treatment of any medical condition is an attempt to alter
the natural history of that condition. If treatment is to be offered,
it must alter the natural history in a positive way. The focus of
our research efforts over the years has been twofold: first, to
examine the natural history of various pediatric orthopaedic conditions
in order to learn their adult consequences and, second, to evaluate the
long-term outcomes of various treatment methods applied to childhood
disorders in order to learn if the natural history had been favorably altered.
This has been possible because of a good record-keeping system,
started by Arthur Steindler, and a stable population base. This
report will give brief highlights of some of these and related studies
in the hope of elucidating the adult consequences of the natural
history and treatment outcomes of childhood disorders. These studies provide
the foundations for current treatment recommendations.
Scheuermann Kyphosis
In 1921, Scheuermann described a so-called spinal deviation that
he believed deserved to be distinguished from passively correctable
postural hunchback30. This condition,
which became known as Scheuermann kyphosis, is characterized by
fixed dorsal kyphosis consisting of wedged vertebrae with disturbances
of the vertebral end plates. In 1964, Sorensen proposed the now
widely accepted radiographic criterion of three adjacent wedged vertebrae
angled by at least 5 degrees to define Scheuermann kyphosis31. The cause of the condition remains
unclear. The round back of Scheuermann kyphosis and the associated
back pain are often causes of concern for patients, parents, and
physicians. There have been many reports that, in an adult, this
condition leads to backache, embarrassment about physical appearance,
interruption of work, disability, severe progressive deformity,
cardiopulmonary failure, tightness of the hamstrings or other muscles, spondylolisthesis,
disc degeneration, and interference with recreational activities.
This has led many authors to recommend early bracing for curves
that are less than 60 degrees and a corrective operation for curves
that are more than 65 degrees.
Despite a thorough review of the literature, my colleagues and
I found little data on the natural history of Scheuermann kyphosis.
Thus, we performed a study to describe the natural history of the
condition23. Sixty-seven patients
who had a diagnosis of Scheuermann kyphosis and an average angle
of kyphosis of 71 degrees were evaluated at an average of thirty-two
years after the diagnosis. The patients were evaluated to assess
pain, work history, social history, neurological function, restrictions of
activities, pulmonary function, range of motion, strength of trunk
muscles, and physical appearance. The evaluations were carried out
with use of a questionnaire, physical examination, radiography,
pulmonary function testing, and testing of the strength of the trunk
muscles. The results were compared with those in a control group
of thirty-four subjects matched for age and gender.
The study demonstrated that patients with Scheuermann kyphosis
had more intense back pain, jobs that tended to have lower requirements for
activity, a more limited range of extension of the trunk, weaker
extension of the trunk, and different localization of pain. No significant
differences between the patients and the control subjects were demonstrated
for the level of education, number of days absent from work because
of low-back pain, extent that the pain interfered with activities
of daily living, presence of numbness in the lower extremities,
self-consciousness, self-esteem, social limitations, use of medication
for back pain, or level of recreational activities. Also, the patients
with Scheuermann kyphosis reported little preoccupation with their
physical appearance.
Patients in whom the kyphosis was less than 100 degrees had normal
or greater-than-normal average values for pulmonary function. The
patients in whom the kyphosis was more than 100 degrees and the
apex of the curve was between the first and eighth thoracic segments
had restrictive lung disease. Five patients had unexplained mildly
abnormal findings on neurological examination, and mild scoliosis
was common. Spondylolisthesis was not observed.
The data from this study suggests that, although patients who
have Scheuermann kyphosis may indeed have some functional limitations,
these limitations do not interfere with their lives in a major way.
The patients who did not have an operation for a kyphosis adapted
reasonably well to this condition.
Spondylolisthesis
During the last century, much has been written about the prevalence,
etiology, and treatment of spondylolisthesis. Very little, however,
has been written about the long-term results in patients in whom
spondylolisthesis has been treated without an operation, especially
in those who have 50 percent or greater displacement of the fifth
lumbar vertebra on the sacrum (a Myerding24 grade-III
or IV lesion). It had not been determined if nonoperatively treated
patients who have a grade-III or IV spondylolisthesis invariably
have disabling pain or disabling neurological symptoms in later
life or to what degree, if any, such patients are limited in their
ability to carry out work or recreational activities.
In situ posterior arthrodesis from the sacrum
to the fourth lumbar vertebra with or without removal of the loose
posterior element of the fifth lumbar vertebra has been the accepted
standard for the operative treatment of spondylolisthesis since Myerding's24 description in 1932, and relief
of symptoms has been reported in the majority of studies. Critics
of in situ arthrodesis, however, have expressed
concern about the reported rates of pseudarthrosis, which have ranged
from 0 to 60 percent11; a rate
of progression of the spondylolisthesis of as high as 25 percent
despite solid arthrodesis; and a persistent cosmetic deformity.
In a previous study, Harris and I examined the outcomes in two
groups of patients who had grade-III or IV spondylolisthesis; one
group did not have operative treatment (Group I, eleven patients),
and the other was treated by posterior interlaminar arthrodesis
(Group II, twenty-one patients)12.
An attempt was made to review the cases of all patients who had
been treated for grade-III or IV spondylolisthesis either nonoperatively
or by an in situ posterior arthrodesis at the University
of Iowa between 1938 and 1980.
The study included a detailed questionnaire; physical examination;
comparison of standing anteroposterior, lateral, and spot lateral
flexion-extension radiographs with the patients' previous radiographs;
measurement of the range of flexion and extension of the spine;
and testing of the strength of the abdominal and extensor muscles. This
data was compared with data that had been previously gathered from
a group of seventy-four normal individuals and had been recorded
in the Spine Diagnostic and Treatment Center Data Base.
After an average eighteen-year follow-up of the eleven patients
in Group I, four patients were asymptomatic, six had mild symptoms,
and only one had severe symptoms. Five patients had one or more
neurological findings, but none were incontinent. All of the patients
in this group led an active life, and all required only minor adjustments
in their lifestyle.
After an average twenty-four-year follow-up of the twenty-one
patients in Group II, twelve patients (57 percent) were asymptomatic,
eight (38 percent) had mild symptoms, and only one (5 percent) had
severe symptoms. Nine (50 percent) of the eighteen patients who
had a physical examination had one or more neurological findings.
Radiographically demonstrated failure of fusion did not adversely
affect the results, and the patients remained asymptomatic despite
the development of pseudarthrosis in one (5 percent) and bending
of the arthrodesis mass in three (14 percent).
Ten of the eleven patients in Group I remained active and required
only minor adjustments in their lifestyle if they had mild symptoms.
Disabling neurological symptoms, disabling pain, or incontinence
of the bowel or bladder did not develop in any patient. Symptoms
were associated with the presence of scoliosis and lateral translatory
shift, tight hamstrings, limited spinal motion, progression of the
spondylolisthesis with time, obesity, weak abdominal muscles, and
neurological findings. Symptoms were not associated with the severity
of the slip. Pregnancy was not complicated by the spondylolisthesis.
The patients limited themselves from few recreational endeavors
and missed little time from work.
The patients in Group II were even less symptomatic and less
restricted in their activities than those in Group I. The degree
of slip at the time of the arthrodesis did not influence the result.
Posterior midline arthrodesis gave predictable, good functional
long-term results in twenty (95 percent) of the patients. Radiographically
demonstrated failure of the arthrodesis, including bending of the
arthrodesis mass, pseudarthrosis, bilateral fracture of the pars
interarticularis cephalad to the arthrodesis mass, degenerative
changes, and instability cephalad to the arthrodesis mass, did not
adversely affect the outcome.
In conclusion, in situ arthrodesis provides
acceptable results for patients who have a grade-III or IV spondylolisthesis and
pain that interferes with their lifestyle and is unresponsive to
nonoperative treatment. In situ arthrodesis is
recommended for skeletally immature patients when there are disturbances
of gait secondary to tight hamstrings and when the spondylolisthesis
is progressive.
Adolescent Idiopathic Scoliosis
My colleagues and I reported the long-term findings and the prognosis
in patients with untreated adolescent idiopathic scoliosis34. Two hundred and nineteen patients
with untreated adolescent idiopathic scoliosis, seen at the University
of Iowa between 1932 and 1948, were studied. Recent information
was available on 194 of these patients, thirty-three of whom had
died. Backache was slightly more common in patients with scoliosis
than in the general population, but it was not disabling. Furthermore,
backache was unrelated to the presence or absence of osteoarthritic changes
or to the severity of the curve. Neither the location nor the degree
of the curve was associated with the psychosocial effects of the
scoliosis. Many curves, particularly thoracic curves measuring between
50 and 80 degrees at skeletal maturity and lumbar components of
combined curves measuring between 50 and 74 degrees, continued to progress
slowly throughout the patient's life. In general, scoliosis did
not cause clinically important limitations in vital capacity or
forced expiratory volume in one second, except in patients who had
a high-angle thoracic curve that approached 100 to 120 degrees.
Patients with a thoracolumbar curve had marked cosmetic deformity
and increasing, although not disabling, backache that was often
associated with translatory shifts and increasing curve severity.
In a second study, Ponseti and I reported on factors that were
related to the progression of adolescent idiopathic scoliosis35. One hundred and thirty-three curves
in 102 patients followed for an average of 40.5 years were evaluated
to quantitate curve progression after skeletal maturity and to determine
prognostic factors leading to that progression. Ninety (68 percent)
of the curves progressed after maturity. Curves less than 30 degrees
at maturity tended not to progress, regardless of the curve pattern.
The Cobb angle, apical vertebral rotation, and Mehta angle were
important prognostic factors in the progression of thoracic curves.
The degree of apical vertebral rotation, the Cobb angle, the direction
of the curve, and the relationship of the fifth lumbar vertebra
to the intercrest line were of value in determining the prognosis
for lumbar curves. Translatory shifts played an important role in curve
progression. Curves that measured between 50 and 75 degrees at maturity,
particularly thoracic curves, progressed the most. Combined curves tended
to balance with age, with the lumbar component progressing slightly
more than the initially larger thoracic component.
I performed a third study, on a select group of fifty-four patients
with a total of sixty-four curves for whom complete radiographs
made at the initial presentation, at skeletal maturity, after thirty
years of follow-up, and after forty years of follow-up were available
for evaluation of radiographic features leading to curve progression37. Analysis of these patients demonstrated
that the radiographic factors identified at skeletal maturity that
led to curve progression predicted progression in skeletally immature
patients as well.
In a recent, not-yet-published study44,
my colleagues and I were able to find information after more than
fifty years of follow-up for 203 (93 percent) of the 219 patients
who were seen at the University of Iowa between 1932 and 1948. In
addition, we found information on twenty-two patients who had been
lost to follow-up at the 1981 review34.
Sixty-nine patients (31 percent) had died. Twenty-eight patients
refused to participate in the new study, and eight had had a spinal
arthrodesis. One hundred and twenty living patients participated
in the study. The patients were an average of sixty-six years of
age and had been followed for an average of fifty-one years (range,
forty-four to sixty-one years). The control group consisted of sixty-two
age and gender-matched volunteers. All patients filled out a detailed
series of questionnaires and had an extensive physical examination,
including complete examination of the deformity, neurological examination,
examination of spinal range of motion and tenderness, and assessment for
nonorganic physical findings. Each patient had an extensive radiographic
evaluation of curve parameters and additional factors previously
elucidated to be predictive of curve progression. The thoracic curves
averaged 83 degrees; the thoracolumbar curves, 91 degrees; the lumbar
curves, 49 degrees; and the thoracic and lumbar components of the
double major curves, approximately 68 degrees.
Compared with the control group, a higher percentage of the patients
with scoliosis reported greater intensity of back pain for a longer
period of time. When duration and intensity of back pain were combined
to reflect the pain experience, the patients with scoliosis had
a much higher pain score than the controls, indicating that they
had worse pain for a longer duration. There were no differences
within the scoliosis group due to curve pattern or magnitude. Fifty-nine
(75 percent) of seventy-nine patients with current radiographs had lumbar
osteoarthritis, and nine patients (11 percent) had thoracic osteoarthritis.
There was no relationship between the pain scores (duration and intensity
of back pain) and the presence or absence of thoracic or lumbar
osteoarthritis. There was no difference in the overall prevalence
of chronic back pain, or with respect to the location of the pain,
across curve patterns. However, there was a significant difference
(p = 0.002) between the patients with scoliosis and the control
patients with regard to the overall prevalence of chronic back pain
and the prevalence in the middle and cephalad lumbar region, and
there were nearly significant differences between the groups with
regard to pain referred to the hip region.
When each of the patient's questionnaires (those completed in
1968, 1978, and 1992) were compared over time, it was found that,
on the average, the patients were experiencing occasional back pain
during the entire study period and the frequency had not increased
since 1968. The frequency of pain did not vary among curve types
within the study period, and when the current responses were examined
there was still no significant association noted between the frequency
of pain and the combined factor of curve type and size. There were
no differences in the prevalence of disabling back pain or its effect
on job status or in the effect of back pain on work and activity
levels between the patients with scoliosis and the control group. There
was also no difference in time lost because of back pain, activity
level, or the ability to perform activities of daily living between
the two groups.
In conclusion, our more-than-fifty-year follow-up study of patients
with adolescent idiopathic scoliosis demonstrated that, although
the patients reported more chronic back pain and acute back pain of
greater intensity and duration, their ability to work and to perform
everyday activities was similar to that of their peers. Despite
back pain, this group of untreated patients continued to function at
a high level, indicating that the natural history of adolescent
idiopathic scoliosis does not necessarily include functional disability.
Slipped Capital Femoral Epiphysis
Slipped capital femoral epiphysis is a disorder in which there
is a gradual or acute displacement through the capital physeal plate.
Much has been learned about the epidemiology, etiology, and pathogenesis
of this condition. The physiolysis is through a widened hypertrophic
zone, which is weakened as a result of altered chondrocyte maturation
and enchondral ossification.
The goals of treatment of slipped capital femoral epiphysis are
to restore function of the hip and to delay the development of degenerative
arthritis by prevention of additional displacement of the epiphysis.
The epiphysis must be stabilized early to accomplish these goals.
The development of degenerative joint disease and the function
of the hip have been reported to be related to the severity of the
deformity, but even mild deformity may play a role in the later
development of degenerative disease. Increased severity of the slip
has been reported to be associated with a longer duration of symptoms.
Marked slipping should be prevented by early diagnosis and prompt
stabilization of the epiphysis.
My colleagues and I performed a study to provide long-term follow-up
of patients who had slipped capital femoral epiphysis and to substantiate
that long-term results are related to the severity of the slip,
to treatment, and to the complications of treatment5. We also wanted to determine if results
deteriorate over time so that we could make recommendations for
treatment on the basis of the initial presentation of the disorder.
The data on 155 hips in 124 patients who had slipped capital
femoral epiphysis was retrospectively reviewed at an average of
forty-one years after the onset of symptoms. The slips were classified,
on the basis of the duration of symptoms, as acute, chronic, or
acute on chronic. As determined by the femoral head-shaft angle,
42 percent of the slips were mild, 32 percent were moderate, and
26 percent were severe. Reduction was performed in thirty-nine hips,
and realignment was done in sixty-five. Of the 142 hips with a chronic
slip, thirty-six (25 percent) had symptomatic treatment only, forty-three
(30 percent) were treated with a spica cast, thirty-four (24 percent) were
treated with pinning, and twenty-nine (20 percent) were treated
with an osteotomy. The Iowa hip rating and the radiographic classification
of degenerative joint disease were determined at the time of follow-up;
both worsened with increasing severity of the slip and when reduction
or realignment had been done. Osteonecrosis (prevalence in series,
12 percent) and chondrolysis (prevalence in series, 16 percent)
were more common with increasing severity of the slip and when reduction
or realignment had been performed; both led to a poor result. Deterioration
over time was most marked with increasing severity of the slip.
The natural history of a malunited slip is mild deterioration
related to the severity of the slip and complications6. Techniques of realignment are associated
with a risk of appreciable complications, and realignment adversely
affects the natural history of the disease. Regardless of the severity
of the slip, pinning in situ provides the best
long-term function and delay in the development of degenerative
arthritis with a low risk of complications.
Legg-Calvç¬erthes Disease
Legg-Calvç¬erthes disease remains one of the most controversial
disorders in pediatric orthopaedics. Many theories regarding the
etiology have been proposed over time. The main feature of Legg-Calvç¬erthes
disease has been described in many histological studies as ischemic
necrosis of the center of ossification of the femoral head. Clinical
observations, however, have suggested that the disease can no longer
be considered a focal vascular accident in the vessels supplying
the capital femoral epiphysis. Children with this disorder have
delayed skeletal maturation and abnormalities with regard to the
proportion of growth in various regions of the body. Several sites
of osteochondritis have been described in the same patient. In children,
a necrotic femoral head following a fracture of the femoral neck
or a traumatic dislocation of the hip often heals rapidly without going
through the prolonged stages of fragmentation or repair that are
observed in Legg-Calvç¬erthes disease. The cause of the ischemia, fragmentation,
and protracted re-formation of the femoral head observed in this
disorder remains unknown.
In a previous specimen from our institution, severe fibrillation
and disruption of the cartilage of the proximal femoral physeal
plate was observed. The purpose of one of our studies was to describe
the histological, histochemical, and ultrastructural observations
of biopsy specimens of the lateral aspect of the femoral head and
neck of five children with Legg-Calvç¬erthes disease in order to
further elucidate the pathobiological characteristics of the condition29.
This study revealed that, beneath the normal articular cartilage,
there was a thick zone of hyaline (epiphyseal) cartilage containing
sharply demarcated areas of hypercellular and fibrillated cartilage
with prominent blood vessels. The fibrillated cartilage was strongly
positive to alcian-blue staining, weakly positive to periodic acid-Schiff staining,
and positive to aniline-blue staining. The interterritorial matrix
in the hypercellular areas was weakly positive to both alcian-blue
and periodic acid-Schiff staining. Ultrastructural examination of
these areas revealed many irregularly oriented, large collagen fibers
and variable amounts of proteoglycan granules. These results suggest
that the fibrillar areas contained a high proteoglycan content,
a decrease in structural glycoproteins, and a different size of
collagen fibrils compared with that of normal epiphyseal cartilage. The
hypercellular areas had a decrease in proteoglycans, glycoproteins,
and collagen. The lateral physeal margin was often irregular, with
a marked reduction of collagen and proteoglycan granules, and it
contained numerous large lipid inclusions. Similar changes have
been described in other Perthes specimens and in specimens from other
epiphyses described in the literature. Irregularities of ossification
and thickened epiphyseal cartilage with areas of calcification in
the so-called unaffected femoral head of a patient with unilateral
disease have also been described in the literature. In addition,
abnormalities in the so-called unaffected hip and several sites
of osteochondritis have been observed in the same patient.
The histochemical and ultrastructural properties of the abnormal
areas of the epiphyseal cartilage of patients with Legg-Calvç¬erthes
disease differ from those of normal cartilage and fibrocartilage. This
suggests that the disease could be a localized expression of a generalized
transient disorder of epiphyseal cartilage that is responsible for
delayed skeletal maturation. Whether the abnormalities of the epiphyseal
cartilage are primary or are secondary to ischemia remains uncertain;
however, it appears that the collapse and necrosis of the femoral head
could result from the breakdown and disorganization of the matrix
of the epiphyseal cartilage followed by abnormal ossification.
Severe deformity of the femoral head develops as a consequence
of the disease and the repair process. These varying deformities
are profoundly influenced by the interrelated factors of age at
the onset of the disease, age at healing, duration of the disease,
extent of epiphyseal involvement, and remodeling potential of the
patient. Legg-Calvç¬erthes disease must be viewed primarily as
a growth disturbance of the epiphyseal cartilage with varying degrees
of premature physeal arrest. The greater the deformity of the femoral
head and the resulting incongruity, the worse the long-term outcome14,36,40.
Before treatment for Legg-Calvç¬erthes disease can be recommended,
it must be shown that the natural history will be altered in a positive
way. Unfortunately, there are few studies of the true natural history
of the disease. The authors of the few such studies that have been
done have used different clinical and radiographic criteria and have
not provided data on interrater and intrarater reliability. Much
can be learned from long-term follow-up studies of patients treated
for Legg-Calvç¬erthes disease36.
These studies, however, have suffered from the faults of most retrospective
long-term reviews. Most series consisted of only a small number
of patients, with many of the original pool of patients not traced.
The patients' original radiographs often were not available. Many
of the longer studies included patients who had been diagnosed with
Perthes disease in the years 1910 to 1940, when little was known
about the disease, prognostic factors, or radiographic classifications.
Thus, all patients were combined regardless of the extent of epiphyseal
involvement, age at the onset of the disease, or age or stage of
the disease at the beginning of treatment. Various treatment modalities
were combined in some series, and the studies generally did not
include control groups. Finally, different methods of evaluation
were often used to evaluate end results.
In follow-up studies performed twenty to forty years after treatment
of Legg-Calvç¬erthes disease, the majority of patients (70 to 90
percent) have been active and pain-free with a generally good range
of motion, despite the fact that few patients have had normal-appearing
radiographs. Clinical deterioration and symptoms of increasing pain,
decreasing range of motion, and loss of function have been observed
only in patients with flattened irregular femoral heads at the time
of primary healing and those with evidence of premature physeal
closure as evidenced by shortening of the femoral neck, deformity
of the femoral head, and overgrowth of the trochanter36.
In an effort to further define the outcomes of patients affected
by Legg-Calvç¬erthes disease, McAndrew and I attempted to contact
patients who had been seen with the disease at the University of
Iowa between 1920 and 194014.
The purpose of the study was to correlate clinical measurements
with the outcome and then to compare the radiographic measurements
with the clinical results. Data was available on thirty-five patients
with thirty-seven affected hips. The average age was 8.2 years at
the onset of symptoms and 55.5 years at the time of follow-up, which
averaged forty-eight years. Significant correlations (no r values
reported) were found between the clinical outcome (as measured with
the Iowa hip-rating scale and on the basis of the prevalence of
arthroplasty) and Catterall head-at-risks signs, femoral head-size
ratio, and age at the onset of the disease. The measurements of
deformity of both the femoral head and the acetabulum and the congruity
of the articular surface did not change appreciably with time. The
Catterall classification alone did not correlate well with the clinical
outcome (no r value reported). When these hips were previously reported
on in 1971, thirty-one (86 percent) of thirty-six hips were functioning
with an Iowa hip rating of greater than 80 points; only three (8
percent) had had an arthroplasty. After an average of forty-eight
years of follow-up, however, only fifteen hips (41 percent) had
maintained a good level of function (a rating of greater than 80
points) and fifteen had had an arthroplasty. An additional four patients
(11 percent) had disabling pain and were awaiting arthroplasty because
of decreasing function and increasing pain. The prevalence of hip pain
and dysfunction was ten times what would be expected in individuals
in the same age range in the general population. There was a strong
correlation between a decrease in the Iowa hip rating at the time
of follow-up and the age at the onset of the disease (no r value
reported).
This study confirmed the findings of others that the age at onset
has a bearing on the long-term outcome, with younger patients having
a better outcome. We found the clinical outcome to be associated
with only three radiographic measurements: the number of Catterall
head-at-risk signs seen during the active period of the disease,
the ratio of the unaffected to the affected femoral head size (width),
and a decrease in the joint space over time. Measurements of the
femoral head, acetabular deformity, and congruency did not change
over time after maturity. Thus, the decrease in the Iowa hip rating
that was seen after skeletal maturity appeared to be related solely
to the development of osteoarthritis.
This study also demonstrated that a good functional outcome can
be expected only if the femoral head is spherical. However, if a
deformity of the femoral head occurs, aspherical congruency may develop
and lead to satisfactory function for many years. Nevertheless,
51 percent (eighteen) of the thirty-five patients in our study had
disabling osteoarthritis by the time that they had reached the sixth
decade of life.
Martinez and I reported a case and reviewed the literature concerning
the rare entity of recurrent Legg-Calvç¬erthes disease17. (Only five cases of recurrent Legg-Calvç¬erthes disease
after complete healing of a previously affected femoral head had
been described, to our knowledge.) The patient whom we described
also demonstrated a change in Catterall classification over time
and lent support to the multiple-infarction theory of etiology.
Furthermore, the case provided evidence that Legg-Calvç¬erthes
disease may represent a generalized disorder of epiphyseal cartilage.
When our patient was first seen, the lesion was classified as Catterall
group I; it subsequently healed. At the time of the onset of the recurrent
symptoms, the radiographic appearance was consistent with Catterall
group-II disease or Salter-Thompson group-A disease, with the subchondral
radiolucent zone extending to less than 50 percent of the femoral
head. Six months later, there was involvement of the entire femoral
head (Catterall group IV or Salter-Thompson group B).
Despite this being only the sixth case reported, recurrent Legg-Calvç¬erthes
disease is probably more common than has been recognized because the
symptoms associated with the first episode are usually minor. The
recurrent episode generally has a poor prognosis because it usually
involves the entire femoral head and occurs when the child is older.
This entity lends support to the theory that multiple vascular interruptions
in a susceptible child cause the disease.
Many authors have expressed considerable pessimism about the
benefits of treatment of Legg-Calvç¬erthes disease. The objectives
of treatment are to decrease pain, to improve the range of motion,
and to prevent deformity of the femoral head that might lead to
osteoarthritis. Long-term function depends on the degree of the
deformity of the femoral head and the congruity of the joint.
The Atlanta Scottish Rite orthosis and its modifications are
the most widely used devices for the treatment of Legg-Calvç¬erthes
disease. However, before the investigation at our institution, only a
few studies, all with short-term follow-up, had been reported. At
the University of Iowa Hospitals and Clinics, we used the weight-bearing
abduction brace for the treatment of hips with severe involvement
(Catterall group III or IV and Salter-Thompson group B), and thus
a poor prognosis, over a fourteen-year period. My colleagues and
I performed a study to analyze the results for these patients, in
order to determine whether the use of a weight-bearing abduction
orthosis had favorably altered the natural history of the disease18. An attempt was also made to determine
whether various clinical and radiographic parameters correlated
with the radiographic result as assessed with the classification
systems of Mose and Stulberg et al.
The most important factor in the long-term prognosis is the extent
of the deformity of the femoral head and the congruity of the joint.
Clinical assessment was not attempted in this study as it is well known
that most patients who have Legg-Calvç¬erthes disease do well in
the short term regardless of the extent of the deformity of the
femoral head14. Thus, the results
were based entirely on radiographic measurements. Thirty-one patients
(thirty-four hips) who had severe Legg-Calvç¬erthes disease (Catterall
group III in five hips and Catterall group IV in twenty-nine hips)
and who had been treated with a weight-bearing abduction orthosis were
evaluated to determine the effectiveness of the brace. The average
age when the patients were first seen was six years (range, three
to twelve years), and the average duration of follow-up was seven
years (range, two to thirteen years). According to the rating system
of Mose, no hip had a good result, only twelve hips (35 percent)
had a fair result, and twenty-two hips (65 percent) had a poor result.
According to the classification system of Stulberg et al., no hip
was considered class I; fourteen (41 percent) were considered class
II (spherical congruent); nine (26 percent), class III; nine, class
IV (aspherical congruent); and two (6 percent), class V (aspherical
incongruent). Twelve hips (35 percent) were considered to have a
change in Catterall classification between the time of the initial
radiograph and the time of maximum fragmentation.
Our patients in whom the lateral column collapsed generally had
a poor outcome. Of the twenty hips in which collapse occurred, only
two (10 percent) had a class-II result according to the system of Stulberg
et al.; seven (35 percent), class III; nine (45 percent), class
IV; and two (10 percent), class V. By comparison, of the fourteen
hips in which the lateral column did not collapse, twelve (86 percent)
had a class-II result and only two (14 percent) had a class-III
result. No hip in which the lateral column did not collapse had
a class-IV or class-V result.
Although containment is the most widely accepted principle of
treatment for Legg-Calvç¬erthes disease, there is very little clinical
information supporting the contention that bracing in abduction and
external rotation, as provided by the Atlanta Scottish Rite orthosis
and its modifications, is effective. On the basis of our results,
we do not support the use of a weight-bearing abduction brace for
the treatment of patients who have severe Legg-Calvç¬erthes disease
(Catterall group III or IV and Salter-Thompson group B).
Congenital Hip Dysplasia and Dislocation
Early studies at our institution defined the normal growth and
development of the hip joint and the morphology of the acetabulum
in congenital dislocation of the hip. Subsequent to these studies,
my colleagues and I began to correlate the arthrographic findings
with the operative pathological findings in congenital dislocation
of the hip13. We evaluated forty-two
children with a total of fifty-six congenital dislocations of the
hip who had been treated by open reduction after failure of attempted
closed reduction. The purposes of this study were to define the
role of arthrography in the management of congenital hip dysplasia
and dislocation and to further define the obstacles to reduction
of congenital hip dislocation and dysplasia. We found that arthrography
gives valuable information about the pathological obstacles preventing
stable concentric reduction. We were able to clearly identify these
anatomical obstacles, which, in order of importance, were the anteromedial
aspect of the joint capsule, the transverse acetabular ligament,
and the ligamentum teres. On arthrograms, the inturned labrum must
be differentiated from the neolimbus of Ortolani as well as its
contribution to the hourglass constriction. Our clinical experience
with arthrographic findings indicated that the neolimbus is rarely
an obstacle to reduction.
Current management of congenital hip dysplasia and dislocation
is based on knowledge of acetabular growth and development, the
pathoanatomy of congenital hip dysplasia and dislocation, the natural
history of untreated congenital hip dysplasia and dislocation, and
ongoing reevaluation of previous treatment methods. If congenital
hip dysplasia and dislocation go undetected, the normal growth and
development of the hip joint are impaired. As the age at the time
of detection increases, particularly beyond six months of age, the obstacles
to concentric reduction (both intra-articular and extra-articular)
become increasingly difficult to overcome13,33,38,41,43.
Closed or open reduction usually must be performed under general
anesthesia. Restoration of normal acetabular development is more
uncertain.
In late-diagnosed cases, the most common obstacle to reduction
is the varying degree of anteromedial constriction of the hip-joint
capsule. Intra-articularly, the ligamentum teres may become hypertrophied
and thickened, and in some cases it may be the primary obstacle
to reduction. In children of walking or crawling age, the ligamentum teres
may be markedly elongated and enlarged. In these cases, its volume
precludes concentric reduction without excision of the ligament.
The transverse acetabular ligament may have become hypertrophied
from the constant pull of the ligamentum teres on its attachment
at the base of the acetabulum. This, in effect, decreases the diameter of
the acetabulum13,33,43. A rare
finding, other than in teratological dislocations, is a true inverted
labrum or limbus (a hypertrophied labrum). The acetabular labrum
may, however, be iatrogenically inverted and be an obstacle to reduction
in patients who were previously treated by unsuccessful closed reduction.
Arthrograms are often misinterpreted as showing an inverted labrum
when in actuality the shadow thought to be the inverted labrum or
limbus is the neolimbus described by Ortolani13,33,41,43.
This neolimbus is epiphyseal cartilage, which is rarely an obstacle
to reduction13,33. It must not
be removed because removal will impair acetabular development. The
extra-articular obstacles to reduction of late-diagnosed cases include
a contracted adductor longus and the iliopsoas.
When the treatment approach is planned, the natural history and
the effects of treatment on the natural history must be kept in
mind. The natural history of completely untreated dislocation varies considerably
and is affected by societal considerations. There may be little,
if any, functional disability. However, in many cases substantial radiographic
degenerative disease leading to a poor clinical result may develop
in a dislocated hip that forms a well developed false acetabulum39.
Residual subluxation of the hip uniformly has a poor prognosis,
with radiographic degenerative joint disease and clinical disability
developing in all patients. The age at which symptoms of radiographic
degenerative joint disease develop is related to the degree of subluxation
and dysplasia. The natural history of acetabular dysplasia in the
absence of subluxation is difficult to predict. Physical signs may
be absent, and the diagnosis may be established only with the onset
of symptoms or as an incidental radiographic finding. There is,
however, a strong association between acetabular dysplasia and degenerative
joint disease in women39,42.
Current treatment concepts must be based on an ongoing reevaluation
of previous treatment regimens. Malvitz and I performed a retrospective study
of 119 patients with 152 congenitally dislocated hips that had been
treated by closed reduction between 1931 and 1969 at the University
of Iowa15. The average age at
the time of the reduction was 21.4 months, and the average age at
the time of follow-up was thirty-one years (range, sixteen to fifty-six
years). At the time of final follow-up, the average Iowa hip rating
was 91 points (range, 38 to 100 points) and the average Harris hip
score was 89.8 points (range, 33 to 100 points). Thirty-five hips
were rated as Severin class I; thirty-five, as class II; twenty-eight,
as class III; fifty-three, as class IV; and one, as class VI. The
prevalence of proximal femoral growth disturbance was 60 percent
(ninety-one hips). In addition, eight contralateral, so-called normal
hips demonstrated evidence of proximal femoral growth disturbance.
In many patients, a partial physeal arrest pattern could not be
determined for ten to twelve years after the reduction. Twelve patients
(seventeen hips) underwent total hip replacement at an average age
of thirty-six years (range, nineteen to fifty-three years).
Patients with growth disturbance of the proximal part of the
femur or evidence of subluxation tended to function extremely well
for many years despite less-than-anatomical radiographic results. Those
with subluxation tended to have more rapid deterioration of function.
The presence of dysplasia was less predictive. Function tended to
deteriorate with time regardless of the presence or absence of proximal
femoral growth disturbance. The rate of subluxation increased with
increased duration of follow-up. Prognostic factors that were predictive
of the late tendency toward subluxation included increased age at
the time of the reduction, increased displacement before the reduction,
and persistent disruption of the Shenton line after the reduction.
The high rate of proximal femoral growth disturbance in this study
may reflect a stricter definition of the term as well as the restriction
of the study to patients who had completed skeletal growth. The
rate of growth disturbance tended to be lower in younger patients
(less than six to twelve months of age at the time of reduction),
but it was a significantly worse disease in those patients. The
younger the patient at the time of the reduction, the better the
clinical and radiographic results and the lower the prevalence of subluxation,
degenerative joint disease, and proximal femoral growth disturbance.
Despite the generally good function at the time of the average thirty-one-year
follow-up, the prognosis remains guarded for these patients.
As a result of the above-mentioned review and in the hope of
avoiding growth disturbance of the proximal part of the femur, a
modified protocol for patients with the late diagnosis of congenital
hip dysplasia and dislocation was established at our institution
in the early 1970s. Our general approach when the hip cannot be
reduced by a Pavlik harness (that is, when such treatment has failed
or the patient is more than six months of age at the time of the
diagnosis) is to attempt a closed reduction under arthrographic
control. Only a perfectly concentric stable reduction is accepted;
otherwise, open reduction is indicated to avoid the severe cartilaginous
damage that has been seen in our patients after closed treatment.
In addition, because of the deterioration of dysplastic hips over
time, we now try to reestablish normal anatomy of the acetabulum
in the hope of avoiding progressive degenerative arthritis; preliminary
results have been promising1-3,21,33,41.
Ponseti and I performed a study of seventeen patients with twenty-two
congenital hip dislocations who had been treated by open reduction
through an anteromedial approach (a modified Ludloff approach) over
a six-year period33. The average
duration of follow-up was 42.2 months. The patients were evaluated
for acetabular development, proximal femoral growth disturbance
(aseptic necrosis), and intraoperative findings. The prevalence
of proximal femoral growth disturbance was 10 percent. The acetabular index
improved rapidly during the first year after the reduction. After
the first year, the rate of acetabular development decreased, but
the acetabular index continued to improve throughout the period of
the study. The anteromedial approach preliminarily provided a safe,
effective way to reduce a dislocated hip in infancy. Through this
approach, adequate release of the extra-articular and intra-articular
obstacles to reduction is easily accomplished. The approach is difficult
to use in patients older than twenty-four months of age. The 10
percent rate of aseptic necrosis in this series was lower than the
rates reported in other series of either closed or open reductions.
This procedure is advocated only when closed reduction cannot be
obtained by gentle manipulation or cannot be maintained by proper,
unforced positioning.
This study underscored several important principles. First, there
is continuing potential for acetabular development that lasts for
several years after reduction. Second, with the anteromedial approach
there is a minimum of soft-tissue dissection, there is no appreciable
blood loss, both hips can be operated on safely at the same session,
and there is a low prevalence of aseptic necrosis. My colleagues
and I have recently reviewed our long-term experience with this
approach21,38.
The reasons for degenerative changes in dysplastic hips are probably
mechanical in nature and related to increased contact stresses with
time42. Given the clear association
of excessive contact stresses with late degenerative changes and
other mechanical disorders (such as genu valgum or varum), my colleagues
and I attempted to investigate whether direct estimates of contact
pressure would correlate with long-term outcome in a large patient
population with an initially well reduced congenitally dislocated
hip10. The purpose of this study
was to determine the long-term pressure-tolerance level of articular
cartilage in patients treated by closed reduction of a congenitally
dislocated hip. The relationship between excessive articular contact
pressure and the long-term outcome was studied in a series of eighty-four
patients with unilateral congenital hip dislocation who were treated
by closed reduction and followed for an average of twenty-nine years. Contact
stress was estimated from archived radiographs made at the time
of maturity and at several follow-up visits. At a recent evaluation,
each patient was examined to determine a clinical rating for pain
and function and a radiographic rating for deformity, degeneration,
and aseptic necrosis. On each of 431 archived radiographs, articular
contact stress (force/area) was estimated mathematically based upon
a frontal plane equilibrium (force) analysis and a landmark-based
inference of three-dimensional head surface area (area). Good correlation
with final deformity (Spearman r = 0.28) was observed when the hips
were ranked in terms of a new cumulative overpressure index, defined
as a time-pressures product involving years of pressure exposure
beyond a two-megapascal pressure damage level. There was an unsatisfactory
outcome in nineteen (90 percent) of twenty-one hips experiencing
a cumulative overpressure of greater than ten megapascal-years (most
of which had aseptic necrosis), whereas the outcome was satisfactory
in 119 (81 percent) of 147 hips with a cumulative overpressure index
of less than ten megapascal-years. Thus, a certain overpressure
(a time-dependent, cumulative pressure exposure) may be associated
with long-term outcome. Aspherical femoral heads (secondary to aseptic
necrosis, for example) would tend to have even more severe overpressure.
At present, it appears that radiographic degenerative joint disease
correlates with the magnitude of overpressure and the time of exposure.
Similar results were reproduced in a second study using two nonuniform
contact models19. The data from
this and our retrospective studies of congenital hip dysplasia and
dislocation10,19 represents, to
our knowledge, possibly the first objective basis for estimating
the intrinsic pressure damage level of human cartilage. We are currently in
the midst of a forty-year follow-up study of the above-mentioned
patients.
Clubfoot
In 1950, a method of treatment of clubfoot that involved gentle
manipulations and plaster holding casts was instituted in the hope
of achieving a mobile, plantigrade, and pain-free foot20. Radiographic studies of anatomical
deformities in treated clubfeet after skeletal maturity are scarce,
and interpreting these deformities is difficult and often confusing.
The severity of the congenital anomaly of the foot and the type
of treatment that was performed determine the final appearance of
the foot. My colleagues and I performed a study to evaluate the
abnormalities in thirty-two patients with unilateral clubfoot deformity
and to correlate the radiographic findings with the functional results28.
The thirty-two patients were followed for thirteen to thirty
years. The functional results were satisfactory in twenty-eight
feet. The skeletal features of the normal feet and the clubfeet
were compared radiographically. Many clubfeet had a small, slightly
flattened talar head; a decreased talocalcaneal angle; undersized,
misshapen facets of the subtalar joint; and a medially displaced
navicular. The residual deformity of the hindfoot was compensated
for by lateral displacement and lateral angulation of the cuneiforms
with respect to the navicular, resulting in normal alignment of
the forefoot in relation to the hindfoot. The ranges of ankle dorsiflexion
and subtalar and midtarsal joint motion were restricted in the clubfeet.
However, most patients noticed little difference in appearance and
function between the normal foot and the treated clubfoot.
This study demonstrated that some of the residual abnormalities
in treated clubfeet present after skeletal maturity and are remnants
of the treatment whereas others represent the carryover of congenital
anomalies into adulthood. In fact, several radiographic changes
observed after skeletal maturity are reminiscent of the anomalies
present in the clubfeet of fetuses and newborns. Our observations
suggest that, although an anatomical correction of the talocalcaneal
angle and the medially displaced navicular is desirable, this is
not necessary to ensure a good clinical outcome. The heel varus
could be adequately corrected in spite of a persisting small talocalcaneal
angle. Proper hindfoot-forefoot alignment in the presence of a medially
displaced navicular could be achieved by angulating and shifting
the cuneiform laterally.
Metatarsus Adductus
Metatarsus adductus (metatarsus varus) is a congenital foot deformity.
Although several studies have been published and numerous theories
have been proposed, the etiology and pathogenesis of the deformity
are unknown. The deformity is present at birth but very often is
diagnosed during the first year of life. The clinical features are
adduction and varying degrees of supination of the forefoot, often
associated with mild heel valgus and internal tibial torsion.
Treatment of metatarsus adductus is controversial. Some authors
have proposed that the deformity is self-resolving when it is passively
correctable but have recommended treatment by manipulations and
plaster casts when the deformity is rigid. Other authors have recommended
operative treatment by various techniques, and some have even recommended
an operation during the first year of life. My colleagues and I
performed a study to evaluate the long-term functional and radiographic
outcome of untreated and nonsurgically treated metatarsus adductus8. To our knowledge, no long-term follow-up
study of metatarsus adductus into adult life had been published
previously.
Thirty-one patients (forty-five feet) with metatarsus adductus
were evaluated. The average duration of follow-up was thirty-three
years. Sixteen feet with a passively correctable (mild or moderate) deformity
at the initial presentation were followed without treatment, and
twenty-nine feet with a partially flexible or rigid (moderate or
severe) deformity at the initial presentation were treated by manipulation
and plaster holding casts. The results were good in all of the untreated
feet and in twenty-six (90 percent) of the twenty-nine feet that
had been treated conservatively. There were no poor results. The
passively correctable deformities corrected spontaneously, and the
partially flexible or rigid deformities were corrected with the
use of a treatment program of manipulation and plaster casts. Radiographs
showed an obliquity of the medial cuneiform-metatarsal joint in
twenty-one (68 percent) of the thirty-one affected feet that were examined
clinically. Similar findings were observed in four (36 percent)
of eleven contralateral, normal feet. Hallux valgus was not a common
final outcome of the metatarsus adductus. Operative treatment should
be reserved only for patients who are at least three years of age
and have a severe and rigid deformity that is not responsive to
conservative treatment.
The described studies as well as other long-term follow-up studies
of pediatric orthopaedic conditions or treatment regimes and related
investigations4,7,9,16,22,25-27,32,45 provide
orthopaedic surgeons with fundamental knowledge necessary to make
intelligent treatment decisions that will ultimately result in improved patient
care.
Note: The author expresses his sincere thanks to the Bristol-Myers
Squibb Foundation and Zimmer Award Selection Committee and to his
nominators. He also thanks the individuals with whom he had the
great privilege of working, over the last twenty-six years, on the
studies that are described in this paper. Most importantly, he thanks
his mentor, colleague, and friend of the last twenty-six years,
Dr. Ignacio Ponseti, for his guidance and inspiration. Dr. Ponseti,
along with the entire faculty at the Department of Orthopaedic Surgery
at the University of Iowa, continues to instill in all trainees
the tenet of Arthur Steindler, which is to always try to understand
the pathoanatomy of a condition, learn its natural history, and
critically evaluate treatment results.
Albinana, J.; Morcuende, J. A.; Delgado, E.; and Weinstein, S. L.: Radiologic pelvic asymmetry in unilateral late-diagnosed
developmental dysplasia of the hip. J. Pediat. Orthop.,15: 753-762, 1995.15753
1995
Albinana, J.; Morcuende, J. A.; and Weinstein, S. L.: The teardrop in congenital dislocation of the hip diagnosed
late. A quantitative study. J. Bone and Joint Surg.,78-A: 1048-1055, July 1996.78-A1048
1996
Albinana, J.; Weinstein, S. L.; Dolan,
L.; and Meyer, M.: DDH acetabular remodeling after closed or open
reduction: timing for secondary procedures. Unpublished data.
Bassett, G. S.; Weinstein, S. L.; and Cooper, R. R.: Long-term follow-up of the fascia lata transfer for the
paralytic hip in myelodysplasia. J. Bone and Joint Surg.,64-A: 360-365, March 1982.64-A360
1982
Carney, B. T.; Weinstein, S. L.; and Noble, J.: Long-term follow-up of slipped capital femoral epiphysis. J. Bone and Joint Surg.,73-A: 667-674, June 1991.73-A667
1991
Carney, B. T., and Weinstein, S. L.: Natural history of untreated chronic slipped capital femoral
epiphysis. Clin. Orthop., 322: 43-47, 1996. 32243
1996
[PubMed]
Davison, B. L., and Weinstein, S. L.: Hip fractures in children: a long-term follow-up study. J. Pediat. Orthop.,12: 355-358, 1992.12355
1992
Farsetti, P.; Weinstein, S. L.; and Ponseti, I. V.: The long-term functional and radiographic outcomes of
untreated and non-operatively treated metatarsus adductus. J. Bone and Joint Surg.,76-A: 257-265, Feb 1994.76-A257
1994
Farsetti, P.; Weinstein, S. L.; Caterini,
R.; and Ippolito, E.: Sprengel deformity, long-term follow-up of
22 cases. Unpublished data.
Hadley, N. A.; Brown, T. D.; and Weinstein, S. L.: The effects of contact pressure elevations and aseptic
necrosis on the long-term outcome of congenital hip dislocation. J. Orthop. Res.,8: 504-513, 1990.8504
1990
[PubMed]
Hammond, G.; Wise, R. E.; and Haggart, G. E.: Review of seventy-three cases of spondylolisthesis treated
by arthrodesis. J. Am. Med. Assn.,163: 175-180, 1957.163175
1957
Harris, I. E., and Weinstein, S. L.: Long-term follow-up of patients with grade-III and IV
spondylolisthesis. Treatment with and without posterior fusion. J. Bone and Joint Surg.,69-A: 960-969, Sept 1987.69-A960
1987
Ishii, Y.; Weinstein, S. L.; and Ponseti, I. V.: Correlation between arthrograms and operative findings
in congenital dislocation of the hip. Clin. Orthop.,153: 138-145, 1980.153138
1980
[PubMed]
McAndrew, M. P., and Weinstein, S. L.: A long-term follow-up of Legg-Calvç¬erthes disease. J. Bone and Joint Surg.,66-A: 860-869, July 1984.66-A860
1984
Malvitz, T. A., and Weinstein, S. L.: Closed reduction for congenital dysplasia of the hip.
Functional and radiographic results after an average of thirty years. J. Bone and Joint Surg.,76-A: 1777-1792, Dec 1994.76-A1777
1994
Mannor, D. A.; Weinstein, S. L.; and Dietz, F. R.: Long-term follow-up of Chiari pelvic osteotomy in myelomeningocele. J. Pediat. Orthop.,16: 769-773, 1996.16769
1996
Martinez, A. G., and Weinstein, S. L.: Recurrent Legg-Calvç¬erthes disease. Case report and
review of the literature. J. Bone and Joint Surg.,73-A: 1081-1085, Aug 1991.73-A1081
1991
Martinez, A. G.; Weinstein, S. L.; and Dietz, F. R.: The weight-bearing abduction brace for the treatment of
Legg-Perthes disease. J. Bone and Joint Surg.,74-A: 12-21, Jan 1992.74-A12
1992
Maxian, T. A.; Brown, T. D.; and Weinstein, S. L.: Chronic stress tolerance levels for human articular cartilage:
two nonuniform contact models applied to long-term follow-up of
CDH. J. Biomech.,28: 159-166, 1995.28159
1995
[PubMed]
Morcuende, J. A.; Weinstein, S. L.; Dietz, F. R.; and Ponseti, I. V.: Plaster cast treatment of clubfoot: the Ponseti method
of manipulation and casting. J. Pediat. Orthop., Part B,3: 161-167, 1994.3161
1994
Morcuende, J. A.; Meyer, M. D.; Dolan, L. A.; and Weinstein, S. L.: Long-term outcome after open reduction through an anteromedial
approach for congenital dislocation of the hip. J. Bone and Joint Surg.,79-A: 810-817, June 1997.79-A810
1997
Muhonen, M. G.; Menezes, A. H.; Sawin, P. D.; and Weinstein, S. L.: Scoliosis in pediatric Chiari malformations without myelodysplasia. J. Neurosurg.,77: 69-77, 1992.7769
1992
[PubMed]
Murray, P. M.; Weinstein, S. L.; and Spratt, K. F.: The natural history and long-term follow-up of Scheuermann
kyphosis. J. Bone and Joint Surg.,75-A: 236-248, Feb 1993.75-A236
1993
Myerding, H. W.: Spondylolisthesis. Surg., Gynec. and Obstet.,54: 371-377, 1932.54371
1932
Noonan, K. J.; Weinstein, S. L.; Jacobson, W. C.; and Dolan, L. A.: Use of the Milwaukee brace for progressive idiopathic
scoliosis. J. Bone and Joint Surg.,78-A: 557-567, April 1996.78-A557
1996
Noonan, K. J.; Dolan, L. A.; Jacobson, W. C.; and Weinstein, S. L.: Long-term psychosocial characteristics of patients treated
for idiopathic scoliosis. J. Pediat. Orthop.,17: 712-717, 1997.17712
1997
Osebold, W. R.; Weinstein, S. L.; and Sprague, B. L.: Thoracolumbar spine fractures. Results of treatment. Spine,6: 13-34, 1981.613
1981
[PubMed]
Ponseti, I. V.; El-Khoury, G. Y.; Ippolito, E.; and Weinstein, S. L.: A radiographic study of skeletal deformities in treated
clubfeet. Clin. Orthop.,160: 30-42, 1981.16030
1981
[PubMed]
Ponseti, I. V.; Maynard, J. A.; Weinstein, S. L.; Ippolito, E. G.; and Pous, J. G.: Legg-Calvç¬erthes disease. Histochemical and ultrastructural
observations of the epiphyseal cartilage and physis. J. Bone and Joint Surg.,65-A: 797-807, July 1983.65-A797
1983
Scheuermann, H.:: Kyphosis dorsalis juvenilis. Zeitschr. Orthop. Chir.,41: 305-317, 1921.41305
1921
Sorensen, K. H.: Scheuermann's Juvenile
Kyphosis, pp. 214-222. Copenhagen, Munksgaard, 1964.
Weinstein, S. L.; Sprague, B. L.; and Flatt, A. E.: Evaluation of the two-stage flexor-tendon reconstruction
in severely damaged digits. J. Bone and Joint Surg.,58-A: 786-791, Sept 1976.58-A786
1976
Weinstein, S. L., and Ponseti, I. V.: Congenital dislocation of the hip: open reduction through
a medial approach. J. Bone and Joint Surg.,61-A: 119-124, Jan 1979.61-A119
1979
Weinstein, S. L.; Zavala, D. C.; and Ponseti, I. V.: Idiopathic scoliosis. Long-term follow-up and prognosis
in untreated patients. J. Bone and Joint Surg.,63-A: 702-712, June 1981.63-A702
1981
Weinstein, S. L., and Ponseti, I. V.: Curve progression in idiopathic scoliosis. J. Bone and Joint Surg.,65-A: 447-455, April 1983.65-A447
1983
Weinstein, S. L.: Legg-Calvç¬erthes
disease: results of long-term follow-up. In The Hip. Proceedings
of the Thirteenth Open Scientific Meeting of the Hip Society, pp.
28-37. St. Louis, C. V. Mosby, 1985.
Weinstein, S. L.: Idiopathic scoliosis. Natural history. Spine,11: 780-783, 1986.11780
1986
[PubMed]
Weinstein, S. L.: Anteromedial approach to reduction for congenital hip
dysplasia. Strat. Orthop. Surg.,6: 2, 1987.62
1987
Weinstein, S. L.: Natural history of congenital hip dislocation (CDH) and
hip dysplasia. Clin. Orthop.,225: 62-76, 1987.22562
1987
[PubMed]
Weinstein, S. L.: The Pathogenesis
of Deformity in Legg Calvç?erthes Disease. Symposium on the Growth
Plate, pp. 379-386. Edited by H. Uhthoff. New York, Raven Press,
1988.
Weinstein, S. L.:: Closed versus open reduction of congenital hip dislocation
in patients under 2 years of age. Orthopedics,,13: 221-227, 1990.13221
1990
Weinstein, S. L.: Congenital hip dislocation: long range problems, residual
signs, and symptoms after successful treatment. Clin. Orthop.,281: 69-74, 1992.28169
1992
[PubMed]
Weinstein, S. L., and Ponseti, I. V.:
Congenital Dislocation of the Hip; Diagnosis, Pathology and Obstacles
to Reduction. Videotape. Rosemont, Illinois, American Academy of
Orthopaedic Surgeons Library.
Weinstein, S. L.; Dolan, L. A.; Spratt,
K.; Peterson, K.; Spoonamore, M.; and Ponseti, I. V.: Natural history
of adolescent idiopathic scoliosis; fifty-year follow-up. Unpublished
data.
Wheeler, M. E.,, and Weinstein, S. L.: Adductor tenotomy-obturator neurectomy. J. Pediat. Orthop.,4: 48-51, 1984.448
1984