The effect of unilateral varus rotational osteotomy with or without pelvicosteotomy on the contralateral hip in patients with perinatal static encephalopathy

Forty-eight patients with perinatal static encephalopathy were treated with unilateral varus rotational femoral osteotomy for hip subluxation. Twenty- one of the 48 also had concomitant pelvic osteotomy. Twenty-seven of the pa tients were nonambulators. Bilateral soft-tissue releases had been per form ed previously in 20 patients. At the time of varus rotational osteotomy, th e mean age was 8 years, 11 months. The indication for a varus rotational os teotomy was femoral head subluxation or dislocation in all cases. The preop erative center-edge angle ranged from -8 degrees to 18 degrees (mean, 4 deg rees), and on the contralateral side, the center-edge angle ranged from 0" to 32 degrees (mean, 19 degrees). The center-edge angle on the operative si de at follow-up averaged 25 degrees (-10 degrees to 78 degrees), an improve ment of 21 degrees, and on the contralateral side averaged 27 degrees (rang e, 9 degrees-40 degrees), an improvement of 8 degrees. Forty-seven patients have had no subsequent surgery on the contralateral hip. One patient had a varus rotational osteotomy on the contralateral hip 5 years postoperativel y; however, this hip was subluxated at the time of the index procedure. Twe lve patients have had no surgery at any time on the contralateral side. Non e of these patients had deterioration of the contralateral hip. Surgery on one hip should not, in itself, be an indication for surgery on the contrala teral concentrically reduced hip with adequate abduction in patients with a cetabular dysplasia secondary to perinatal static encephalopathy.