Background: The treatment of Legg-Calvé-Perthes disease has
been based on uncontrolled retrospective studies with relatively small numbers
of patients. This large, controlled, prospective, multicenter study was
designed to determine the effect of treatment and other risk factors on the
outcome in patients with this disorder.
Methods: We enrolled 438 patients with 451 affected hips in a
prospective multicenter study in which each investigator applied the same
treatment method to each of his or her
patients*. The five treatment
groups consisted of no treatment, brace treatment, range-of-motion exercises,
femoral osteotomy, and innominate osteotomy. All patients were between 6.0 and
12.0 years of age at the onset of the disease, and none had had prior
treatment. Three hundred and forty-five hips in 337 patients were available
for follow-up at skeletal maturity. All hips were classified with the modified
lateral pillar classification and the system of Stulberg et al.
Results: There were no differences in outcome among the hips with no
treatment, those treated with bracing, and those treated with range-of-motion
therapy. There were also no differences between the hips treated with a
femoral varus osteotomy and those treated with an innominate osteotomy.
Treatment did not have a significant effect on children who had a chronologic
age of 8.0 years or less or a skeletal age of 6.0 years or less at the onset
of the disease. In the lateral pillar B group and B/C border group, the
outcomes of surgical treatment were significantly better than those of
nonoperative treatment in children over the age of 8.0 years at the onset of
the disease (p = 0.05). Patients who were 8.0 years old or less at the
onset of the disease in lateral pillar group B did equally well with
nonoperative and operative treatment. Hips in lateral pillar group C had the
least favorable outcomes, with no differences between the operative and
nonoperative groups. The lateral pillar classification (p < 0.0001) and the
age at the onset of the disease (p = 0.0001) were both strong prognostic
factors. Female patients did significantly worse than male patients if they
were over the age of 8.0 years at the onset of the disease (p = 0.004).
Conclusions: The lateral pillar classification and age at the time
of onset of the disease strongly correlate with outcome in patients with
Legg-Calvé-Perthes disease. Patients who are over the age of 8.0 years
at the time of onset and have a hip in the lateral pillar B group or B/C
border group have a better outcome with surgical treatment than they do with
nonoperative treatment. Group-B hips in children who are less than 8.0 years
of age at the time of onset have very favorable outcomes unrelated to
treatment, whereas group-C hips in children of all ages frequently have poor
outcomes, which also appear to be unrelated to treatment.
Level of Evidence: Therapeutic study, Level II-1
(prospective cohort study). See Instructions to Authors for a complete
description of levels of evidence.