Severity of hip dysplasia as the major factor affecting outcome of closed reduction in children with hip dysplasia.

The objective of this study was to analyze a multicenter cohort of children with developmental dysplasia of the hip (DDH) who underwent treatment with closed reduction. We sought to report the effects that severity of hip dysplasia and age have on the development of femoral head avascular necrosis (AVN) and the need for additional procedures. All patients with DDH and minimum 2 years of follow-up who underwent closed reduction were identified. The following variables were recorded: sex, laterality of hip involvement, age, acetabular index (AI), and International Hip Dysplasia Institute (IHDI) grade. The effects of patient age and pre-procedure IHDI grade on the rate of AVN and need for additional procedures after the closed reduction were analyzed using an alpha of 0.05. Seventy-eight total hips were included in the final analysis. The average patient age was 12 months. AVN of the femoral head was reported in 24 hips (30.8%) and 32 hips (41.0%) required additional surgery. Higher pre-op IHDI grade was associated with higher risk of developing Bucholz-Ogden grades II-IV AVN of the femoral head (P = 0.025) and requiring additional surgery (P= 0.033) regardless of patient age. There were no statistically significant differences for the effect of age on the measured outcomes (P > 0.05). These findings suggest that severity of dislocation (IHDI grade) is a significant risk factor for the development of AVN and need for additional procedure.

Outcomes of Open Reduction in Children With Developmental Hip Dislocation: A Multicenter Experience Over a Decade.

BACKGROUND: Open reduction of the hip is commonly performed in children with severe developmental dysplasia of the hip, or in cases that are refractory to nonoperative forms of treatment. The open reduction has been associated with numerous complications including avascular necrosis (AVN) of the femoral head, the need for reoperation, and residual radiographic dysplasia. This study seeks to determine the effects of preoperative severity of dysplasia, associated procedures (femoral and acetabular osteotomies), age on AVN, and the need for reoperation. METHODS: Children with developmental dysplasia of the hip and a minimum of 2 years of follow-up who underwent open reduction were identified. The following data points were recorded: sex, laterality of hip involvement, simultaneous procedures, surgical approach used, age, acetabular index, and International Hip Dysplasia Institute grade. We analyzed the effects of preoperative International Hip Dysplasia Institute, age, surgical approach (anterior/medial), bilateral reduction, and simultaneous femoral shortening or pelvic osteotomy on the outcomes of AVN and reoperation. RESULTS: One hundred eighty-five hips in 149 patients were included in this study with an average follow-up of 4 years (range: 2 to 5 y). The average age at index surgery was 23 months (range: 1 to 121 mo). Overall, 60 hips (32.4%) required secondary surgical procedures at an average age of 58.5 months. High-grade AVN was noted in 24 hips (13.0%) and was found to be associated with the severity of the hip dislocation ( P = 0.02). A higher rate of reoperation was found in children over 18 months at the time of open reduction who did not receive an acetabular osteotomy ( P = 0.012). CONCLUSION: Approximately 1/3 of patients require another operative intervention within the first 4 years after open reduction of the hip. We found the severity of hip dislocation to be associated with a higher risk of AVN development. These findings support performing an acetabular osteotomy in children over 18 months of age at the time of open reduction to decrease the likelihood of requiring future reoperation during the first 4 years after the index procedure. LEVEL OF EVIDENCE: Level III.