Clinical outcomes of conservative treatment with a non-weight-bearing abduction brace for Legg–Calvé–Perthes disease

Background Treatment with a brace is the first choice as conservative treatment via the containment method for Legg–Calvé–Perthes disease (LCPD). The purpose of this study is to evaluate clinical outcomes and influential factors of conservative treatment with the non-weight-bearing abduction brace for LCPD. Methods One hundred thirty hips in 130 patients were examined in this study. The mean age at onset was 7.0 years (3.3–12.4 years) and the mean follow-up period was 8.4 years (4.1–17.6 years). The extent of necrosis and lateral collapse of the femoral head were evaluated using the Catterall classification and the lateral pillar classification, respectively. Radiological outcome was assessed as good (classes I and II), fair (III), and poor (IV), according to the modified Stulberg classification. Results Radiographic outcome at final follow-up was good in 82 hips (63%), fair in 40 hips (31%), and poor in 8 hips (6%). Multinomial logistic regression analysis showed that major influential factors for good outcomes were as follows: age at onset, lateral pillar classification, and Catterall classification. From the receiver operating characteristic curve, the cut-off value for age at onset was 8.4 years old to obtain good outcomes. Hips with Catterall group I and II and lateral pillar group A and B had significantly better results. Conclusion Patients younger than 8.4 years old at onset with lateral pillar group A or B or Catterall group I or II showed good outcomes with a non-weight-bearing abduction brace for LCPD. These results show that alternative treatment, such as surgery, may be another option for patients who are not included in the above groups.