Comparison of two methods of early treatment in developmental dislocation of the hips

Abstract

Objective To compare the early treatment results of Pavlik harness and closed reduction plus spica casting in treating developmental dislocation of the hips (DDH). Methods The patients with Graf Ⅲ/Ⅳ type DDH diagnosed by ultrasound in our hospital were analyzed retrospectively from January 2009 to December 2013. The subjects with intact clinical and radiologic data and more than 2 years follow-up were included. The present study included 257 patients (298 hips), 31 male and 226 female, with the average age of 74.1±39.2 d (from 30 to 159 d). Pavlik harness underwent in 190, while 67 cases were treated with closed reduction plus spica casting. Acetabular index (AI), Wiberg OE angle (point O was the middle point of proximal metaphyseal border) and Smith instability index (SI, SI-c: the lateral displacement index, SI-h: the vertical displacement index) on the pelvic X-ray film at 2-3 years of age after successful early treatment were recorded. Femoral head avascular necrosis (AVN) was diagnosed according to the Salter criteria. Results The success rate of reduction of closed reduction was significantly higher than Pavlik harness (97.5% vs. 69.9%, χ2=0.353,P=0.000). There was no significant difference in the incidence of AVN between the closed reduction and Pavlik harness (6.6% vs. 4.6%, χ2=0.106,P=0.745). For Graf Ⅲ type DDH, the success rate of reduction of Pavlik harness and closed reduction were 80.7% and 98.4% respectively (χ2=11.248,P=0.001), while the Pavlik harness group had significantly worse results of AI, OE and SI-c at the age of 2-3 years (Pavlik harness: 22.9°±3.7°, 16.5°± 6.3° and 0.74±0.06; closed reduction: 21.4°±3.4°, 18.9°±3.6° and 0.72±0.03;P<0.05). For Graf Ⅳ type DDH, the success rate of reduction of Pavlik harness was much less than closed reduction (25.6% vs. 94.4%, χ2=24.231,P=0.001), with significantly worse results of OE at the age of 2-3 years (16.0°±4.1° vs. 18.6°±4.5°,t=-2.141,P=0.038). Conclusion Pavlik harness has limitations in treating Graf Ⅲ/Ⅳ type DDH, with lower success rate of reduction for Graf Ⅳ type DDH. Closed reduction plus spica casting has better clinical results than Pavlik harness in success rate of reduction and subsequent hip development without the additional risk of AVN. Key words: Hip dislocation, congenital; Bone diseases,developmental; Orthopedic fixation devices