Does arthroscopic excision of a femoroacetabular impingement lesion improve function in patients with hip osteoarthritis?

Clin Orthop Relat Res, Dec 2010
Larson CM, Giveans MR, Taylor M.
Earlier studies reporting the effect of osteoarthritis on pain and function after hip arthroscopy predate the establishment of arthroscopic excision of femoroacetabular impingement (FAI).
The aim of the researchers was to assess the improvement in function after excision of a femoroacetabular impingement lesion in patients with radiographic narrowing of the joint space preoperatively, and to identify possible preoperative predictors of the level of pain and function, as well as the failure rates in these patients.
Between 2004 and 2008, 210 patients (227 hips) with a femoroacetabular impingement lesion were treated by hip arthroscopy and were followed for a minimum of 12 months (mean, 27 months). The group with a femoroacetabular impingement lesion comprised 154 patients (169 hips) without radiographic narrowing of the joint space, while the group with femoroacetabular impingement and hip osteoarthritis comprised 56 patients (58 hips) with radiographically observed narrowing of the joint space (early hip osteoarthritis). Assessment was made with the Harris hip score (HHS) and the Short Form-12 (SF-12) questionnaire, while pain was assessed with a visual analogue scale (VAS) preoperatively and postoperatively.
The improvement in the outcome scores was greater for the group with a femoroacetabular impingement lesion than for the group with a femoroacetabular impingement lesion and hip osteoarthritis. The overall failure rate was higher for the group with femoroacetabular impingement and hip osteoarthritis (52%) than for the group with femoroacetabular impingement (12%). Although the patients with narrowing of the joint space of less than 50%, or with a joint space greater than 2 mm on the preoperative radiographs, had improved scores throughout the study, no improvement was observed in any score in the patients with advanced narrowing of the joint space. Thus advanced narrowing of the joint space, advanced chondral lesions on MRI and a longer duration of preoperative symptoms predicted lower scores.
The researchers concluded that correction of femoroacetabular impingement when it is accompanied by mild narrowing of the joint space brings about improvement in pain and function in the medium term. Patients with severe narrowing of the joint space do not improve and are not candidates for correction of femoroacetabular impingement.