Outcome of patients with Legg-Calvé-Perthes onset before 6 years of age.

BACKGROUND: The prognosis of Legg-Calvé-Perthes disease (LCPD) in young patients has been accepted as favorable. The purpose of this study was to clarify the outcome of LCPD patients with onset before 6 years of age.

METHODS: From 1989 to 2007, of 332 LCPD patients, 114 hips (in 100 patients) were diagnosed before 6 years of age (mean age, 4.5 y old) with subsequent repair of the epiphysis in all cases. Waldenström classification at presentation was initial stage in 76 hips and fragmentation stage in 38 hips. Lateral pillar classification was group A in 17 hips, group B in 22 hips, group B/C in 24 hips, and group C in 51 hips. Treatment methods were observation with restriction of activity alone in 42 hips and several containment treatments in 72 hips.

RESULTS: At the mean age of 14, Stulberg classification was class I in 26 hips, II in 46 hips, III in 28 hips, and IV in 14 hips. These data show an acceptable outcome in 72 of 114 hips (63%). Logistic regression analysis revealed that lateral pillar classification (odds ratio, 3.6) and good range of abduction without treatment (odds ratio, 4.0) were prognostic factors.

CONCLUSIONS: Poor outcome was observed even in patients before 6 years of age with large necrotic area. Lateral pillar classification and good range of abduction were prognostic factors.

LEVEL OF EVIDENCE: Level IV. Therapeutic studies-investigating the results of treatment. Case series.