Anterior approaches to the hip for the treatment of femoro-acetabular impingement: a cadaveric study.

Femoroacetabular impingement (FAI) may be a cause of early osteoarthritis of the hip. The aim of surgical treatment is to improve the head-neck offset in the presence of a cam lesion and to perform acetabular rim resection when pincer impingement is evident, either by open surgery or arthroscopically. We investigated two mini anterior approaches to the hip joint based on the Heuter and direct anterior approach to assess their potential for treating FAI. The two approaches were employed in 20 hips in 10 human cadaveric specimens. The area of femoral head and the portion of the acetabular rim that could be exposed was documented. We found that the two approaches were easy and reproducible. Both allowed adequate exposure to the femoral head. The area of acetabular rim accessible varied significantly according to the approach (p<0.05). We also found that the position of the anterior inferior iliac spine in relation to the acetabular rim also affected the area of acetabular rim exposed (p<0.05). In summary, cam and pincer impingement of the hip can be treated by either the direct anterior or by the Heuter approach. The choice of approach is dictated by the site of the acetabular pincer lesion identified on pre-operative imaging, with a more medial exposure possible through the direct anterior approach and more anterolateral exposure via the Heuter approach.