Hemiepiphysiodesis for the correction of angular deformity about the knee.

BACKGROUND: It is generally accepted that the presence of angular deformity about the knee that persists into the preadolescent years will not correct spontaneously. The goal of this study was to review our experience with hemiepiphysiodesis and physeal stapling for the correction of angular deformity to establish the efficacy of these procedures and to determine their indications and the rate of correction.

METHODS: A retrospective review of 48 patients undergoing hemiepiphysiodesis or physeal stapling about the knee was performed. Patients were included if they had at least 2 years of documented follow-up without an osteotomy.

RESULTS: The average follow-up was 30.4 months (range, 24-52 months). Genu varum was identified in 33 patients, genu valgum in 14 patients, and a windswept deformity in 1. Of the 52 limbs with genu varum, 35 were secondary to Blount disease. The group with genu varum unrelated to Blount disease presented a change in the mechanical axis from a mean of -32 degrees at surgery to a mean of - 13 degrees. The patients with Blount disease presented a change in the mechanical axis from a mean of -19 degrees at surgery to a mean of -16 degrees. The group with genu valgum presented a change in the mechanical axis from a mean of 20 degrees at surgery to a mean of 2 degrees.

CONCLUSIONS: Hemiepiphysiodesis is an effective means for correcting angular deformity about the knee in skeletally immature patients with both genu valgum and genu varum, so long as the genu varum is unrelated to Blount disease. Hemiepiphysiodesis is effective in preventing the progression of deformity in patients with Blount disease.

LEVEL OF EVIDENCE: Therapeutic-Level IV.