Fixation with poly-L-lactide screws in hip osteotomies.

UNLABELLED: The purpose of our study was to investigate the bone union rates and complication rates, including breakage of screws, infection, and osteolysis, in hip osteotomies using poly-L-lactic screws. We prospectively followed up 111 hips in 100 patients using conventional radiography, in which 81 rotational acetabular osteotomies, 26 Chiari pelvic osteotomies, and four Sugioka's transtrochanteric osteotomies were performed. The mean age of the patients at the time of surgery was 34 years, and the mean followup was 5.4 years. Eighty-one osteotomized acetabula and 98 osteotomized greater trochanters were fixed using poly-L-lactic screws. These hips were compared with 64 hips in 58 patients using metallic screws. Bone union was achieved in 80 of the 81 acetabular osteotomies, except in one hip with postoperative deep infection. Proximal displacement of the greater trochanter because of poly-L-lactic screw breakage occurred in six (6%) hips. None of the metallic screws broke. Osteolysis occurred in one hip with a trochanteric osteotomy using poly-L-lactic screws. Poly-L-lactic screws are suitable to transfix the osteotomized acetabulum, but there is some risk of fracture when used to reattach an osteotomized greater trochanter. Complete bone ingrowth in the screw channels cannot be expected for several years after insertion. Osteolysis is a possible complication.

LEVEL OF EVIDENCE: Therapeutic study, Level II (prospective comparative study). See the Guidelines for Authors for a complete description of levels of evidence.