Injury to the growth plate after Pemberton osteotomy

The Pemberton osteotomy involves cutting directly into the iliopubic and il ioischial limbs of the triradiate cartilage of the acetabulum. Complete clo sure of the triradiate cartilage after this osteotomy has been described in case reports. The present experimental study was performed to determine wh ether physeal osseous bars formed after Pemberton osteotomy. Eight Pemberton osteotomies were performed in six piglets. The animals were killed, and the acetabula were studied with use of radiography, computed t omography, and histological analysis for evidence of physeal injury. Plain anteroposterior radiographs of the pelvis did not clearly demonstrate the formation of osseous bars. However, Bucholz radiographs, made with the acetabulum placed directly on the cassette, showed osseous bars in three o f the four specimens that were studied in this manner. Histological section s of the eight specimens of triradiate cartilage demonstrated five osseous bars in the iliopubic limb and four in the ilioischial limb. In two specime ns, there was disruption of the cartilage without osseous bridging. Only tw o of the eight specimens had normal histological findings in both the iliop ubic and the ilioischial limb of the triradiate cartilage. CLINICAL RELEVANCE: The results of the present study demonstrate that cross ing the triradiate cartilage with an osteotome can cause the formation of a n osseous bar in the triradiate cartilage. Such a bar may cause growth arre st and could lead to acetabular dysplasia secondary to disturbance of norma l pelvic growth.