Results of femoral varus osteotomy in children older than 9 years of age with Perthes disease.

We review the results of varus osteotomy in 17 patients older than 9 years of age with 18 hips affected by Perthes disease. Seventeen hips were judged as Catterall 3 or 4, and 14 hips had partial or complete loss of the lateral pillar. At an average follow-up of 10 years (4.2-17.8 years), 3 hips were rated Stulberg 1, 3 were Stulberg 2, 4 were Stulberg 3, and 8 were Stulberg 4 or 5. At follow-up, 7 hips were considered good or fair based on the use of Mose circles. Statistical analysis indicated better results in patients younger than 10 years of age compared with those older than 10 years of age. Varus osteotomy as a method of containment for Perthes disease provides improved results in children older than 9 years compared with natural history studies or studies of noncontainment methods. However, it seems likely that there is an upper age limit for effectiveness of containment treatment.