Stapling of knees with valgus deformity in children with juvenile chronic arthritis.

OBJECTIVE: Leg length discrepancy and excessive knee valgus are potential complications of juvenile chronic arthritis of the knee. The aim of the present study was to evaluate retrospectively the safety and efficacy of temporary stapling of the knee epiphyses in management of valgus deformities of the knee in children with JCA.

METHODS: Medical data of the patients with temporary epiphyseodesis due to knee valgus deformity (KVD) were studied. 177 knees in 112 patients were found with sufficient data for evaluation. Patient documents and radiographs of these patients were evaluated.

RESULTS: Mean age at the time of operation was 8 years (range: 2 - 17) in 19 males and 93 females. The patients are predominantly affected by aggressive polyarticular disease. Preoperative mean valgus angle was 11 degrees (IQR: 9, 14) and at staple removal 4 degrees (IQR: 2, 5). In 120 of 177 knees (68% [95% CI: 61 - 74], p < 0.001) the physiological angle (3-8 degrees) was reached. Median time of stapling was 10 months (IQR: 8, 13). Five reversible and one irreversible (3% [95% CI: 2 to 7]) major complications were documented among the 177 stapled knees.

CONCLUSION: Temporary epiphyseal stapling enables flexible correction of KVD in children with JCA. Low complication rate encourages the use of the method. Prompt follow-up is, however, important in avoing excess over-correction to varus.