Hip osteochondral lesions: arthroscopic evaluation.

Background: Hip arthroscopy has allowed the diagnosis and treatment of chondral injuries.

Methods: We retrospectively analysed the intraoperative data of 359 patients treated with hip arthroscopy from January 2012 to December 2013. We estimated the frequency, location and extension of acetabular cartilage (AC) injuries and their correlation to femoroacetabular impingement (FAI).

Results: Grade 1 and 2 acetabular chondral lesions were not statistically significant in incidence, location and extension. Chondral lesions were absent on the acetabulum in 3.9% of cases, significantly lower compared to the femoral head (32.0%). 101 (28.1%) were affected by an acetabular chondral lesion. In 244 (68.0%) the chondral lesion was located on both acetabulum and femoral head. On the acetabulum, peripheral superior and superior-posterior area were frequently involved. Grade 4 acetabular chondral defects showed a significant high location on the superior-anterior, superior and superior-posterior area, involving both the peripheral and central surface. Delamination was present in 113 (31.5%) patients. Patients affected by acetabular delamination showed a reduced injury extension if compared to grade 3 or 4. 81 patients (25%) revealed acetabular chondral lesions grade 2a, 3 and 4 without any radiological, clinical or arthroscopic sign of FAI.

Conclusions: Location, extension and degree of hip chondral lesions show a progression toward a progressive degeneration. The high percentage of chondral delamination in the hip must be taken in consideration. The presence of symptomatic chondral lesion in cases with no radiological evidence of FAI, suggests that their aetiopathogenesis could be related to biomechanical alterations.