Short-term effects on arthroscopic-assisted surgery for irreducible or unstable developmental dislocation of the hip in infants

Abstract

Objective To explore the short-term effects on arthroscopic-assisted surgery for irreducible or unstable developmental dislocation of the hip (DDH) in infants. Methods From April 2009 to September 2010, 15 children (16 hip) with irreducible or unstable DDH undergoing arthroscopic-assisted surgery were followed up. The operative duration, blood loss and obstructions for hip reduction were recorded. Modified McKay grading was used for evaluating the hip joint functions. Acetabular index (AI), acetabular head index (AHI), avascular necrosis (AVN) and Severin's classification were used for evaluating the radiographic findings. Results The average operative duration was 123 min and average amount of blood loss 4.8 milliliter. The obstructions for hip reduction included a proliferation of soft tissue in acetabular fossa, hypertrophic ligament teres, acetabular transverse ligament and inverted labrum. All patients were successfully reduced. There was no onset of infection or nerve injury. The average follow-up period was 32 (6-59) months. Six patients were followed up recently. According to the Barrett's modified McKay criteria, the outcomes were excellent (n=3), good (n=1), fair (n=3) and poor (n=1). Based upon the Severin criteria, 4/8 hips (50%) were graded Severin I, II. And 7/16 hips (43.8%) showed sign of AVN. Kalamchi-MacEwen type wasⅠ(6 hips) and Ⅱ (1 hip). Conclusions Arthroscopic-assisted surgery for irreducible or unstable DDH in infants is both safe and mini-invasive with less bleeding and a high rate of stable reduction. AVN may be related with modified hip spica and residual acetabular dysplasia is probably caused by not performing acetabular osteotomy. Key words: Arthroscopy; Dislocation of hip joint; Reduction