Coxa vara in postseptic arthritis of the hip in children.

The behavior and treatment of coxa vara and pseudarthrosis of the proximal femur secondary to sepsis is not well described. The aim of this study is to describe the pathoanatomy for coxa vara and pseudarthrosis in postseptic hips, evaluate progression of neck shaft angle (NSA), and discuss treatment. This is a retrospective case series of 20 patients (21 hips). There were 11 hips with predominant avascular necrosis of the capital femoral epiphysis without pseudarthrosis (type 1) and 10 with pseudarthrosis (type 2). The interobserver κ value was 0.79. There was a decrease in NSA from 110.3° to 99.3° during an average follow-up duration of 5.2 years (range: 2-14 years). The average change in NSA between the initial presentation and the final follow-up was 5.5° in type 1 and 17.1° in type 2. Nine patients underwent a surgical intervention. In cases where subtrochanteric valgus osteotomy was performed, the mean preoperative NSA was 94° and the mean NSA at the final follow-up was 128°; all operated pseudarthroses healed without bone grafting. Acetabuloplasty is not necessary in most cases.

Management of post septic hip dislocations when the capital femoral epiphysis is present.

Delayed or missed diagnosis of septic arthritis of hip in children results in various sequelae. The group of post septic hip dislocations when the capital femoral epiphysis (CFE) is present has not been described in the commonly used classifications. This is a retrospective series of 21 hips in 18 children. The presence of the CFE was confirmed radiologically or at the time of intervention. The mean follow-up after intervention was 6.3 years. Interventions for dislocations included closed reduction ± adductor tenotomy, open reduction ± supplementary femoral procedures, and acetabular procedures. Results were evaluated clinically with Ponseti hip scoring and radiologically with the modified Severin grading. Closed reduction was successful in seven of 20 hips (35%) and open reduction in 13 of 14 hips. At follow-up, good clinical result was seen in nine of 18 cases (50%). The mean neck shaft angle was 129° in all hips and 124° after femoral varus osteotomy. There was one redislocation and three subluxations. The modified Severin classification was class 2 in five hips (good), class 3 in 12 hips (fair), class 4 in three hips (poor), and class 6 in one hip (failure). Septic hip dislocation with CFE present is a distinct entity. MRI is helpful for planning treatment. A significant number of patients need open reduction with other procedures. Femoral varus osteotomy may contribute to coxa vara. In the short term, intervention results in a stable, functional, and mobile hip.