Arthroscopic reduction and acetabuloplasty for the treatment of dislocated hips in children of walking age: a preliminary report.

INTRODUCTION

This paper presents our initial findings on the use of arthroscopic hip reduction in conjunction with acetabuloplasty to treat patients of walking age who had congenital dislocation of the hip.

MATERIALS AND

METHODS

Arthroscopic reduction with acetabuloplasty was performed on nine children of walking age with nine dislocated hips. The average age of the patients was 21.4 months (14-41 months). Arthroscopic reduction was performed using a two-portal method with a 2.7-mm mini cannulated arthroscopic instrument. We used a subadductor portal and a high anterolateral portal. The obstacles preventing reduction-hypertrophic teres ligament, pulvinar, capsular constriction, hypertrophic transverse ligament-were eliminated.

RESULTS

We treated one grade 4 hip, four grade 3 hips and four grade 2 hips, as classified by Tönnis. We were able to perform arthroscopic reduction on all of the hips. The main obstacles preventing reduction were a capsular constriction and a hypertrophic teres ligament. During the investigation period, which averaged 15.4 months (6-29 months), no repeat dislocation occurred. According to the Tönnis classification system for avascular necrosis, there were two cases of a grade 2 necrosis of the femoral head. The average preoperative AC angle was 40° (34°-47°). The average AC angle at the follow-up examination was 18.7° (11°-27°).

CONCLUSIONS

We can conclude that the standardized arthroscopic surgical technique presented here can also be used to safely perform arthroscopic reduction in toddlers. The new arthroscopic method is an alternative to open reduction for selective hip dislocations. We believe this approach can be used to treat dislocated hips that are classified as grades 2 and 3 dislocations according Tönnis. Early results are promising. Medium-term results are needed to make a definitive statement on the rates of necrosis of the femoral head.