Abstract

BACKGROUND: Developmental dislocation of the hip (DDH) results in osteoarthritis in infants and children. This study aimed to investigate the effects of a single approach to arthroscopic reduction and debridement on clinical outcome in 12 infants with DDH.

MATERIAL AND METHODS: Twelve infants with irreducible DDH underwent single approach arthroscopic reduction and debridement followed by the use of a frog-leg position plaster cast with fixed flexion and abduction of the hips combined with external fixation for 6–8 weeks. Magnetic resonance imaging (MRI) or plain X-ray images were analyzed. Intra-articular obstructive factors for reduction were evaluated. The safety angle, medialization rate of the femoral head, and the acetabular angle were measured before and after arthroscopic reduction.

RESULTS: Imaging showed that the signs of DDH were significantly improved following arthroscopic reduction. Obstructive factors included hypertrophy of the round ligament, fibrous tissue and fat in the acetabular base, arthrocapsular constriction, and varus deformity of the hip. The safety angle was significantly increased following arthroscopic reduction (53.5°) compared with the safety angle before treatment (18.5°) (p<0.05). Medialization of the femoral head was significantly increased (127%) compared with that before treatment (72%) (p<0.05). Arthroscopic reduction significantly reduced the acetabular angle (25°) compared with that before treatment (37.5°) (p<0.05).

CONCLUSIONS: Single approach arthroscopic reduction and debridement was an effective method for treating DDH that significantly improved the medialization rate of the femoral head, acetabular angle, and the outcome of external fixation when a plaster cast was used with fixed flexion and abduction of the hips.

Keywords: Arthroscopy, Hip Dislocation, Congenital, Osteoarthritis, Hip, Acetabulum, Debridement, Femur Head, Hip Dislocation, Hip Joint, Infant, Joint Diseases, Joint Dislocations, Magnetic Resonance Imaging, Treatment Outcome