Purpose of the study: We conducted a retrospective study of 66 cases of non-traumatic osteonecrosis of the femoral head by percutaneous drilling and autograft. This technique associated drilling with graft conductor effects and bone marrow inducers.
Material and Methods: Forty-six patients (41 male, 5 female) with non-traumatic osteonecrosis were included in this study. Mean age at surgery was 46 years (22–68). The 66 cases involved 32 right hips and 34 left hips (21 bilateral cases), six asymptomatic. Osteonecrosis was related to corticosteroid therapy (n=17), chronic ethylism (n=14), dyslipidaemia (n=7), barotraumatism (n=3), and renal transplantation (n=1). Four were found idiopathic. The preoperative ARCO classification was: 8 stage IIA, 21 stage IIB, 15 stage IIC, 7 stage IIIB, 13 stage IIIC and 2 stage IV. A minimally invasive surgical technique combined simple percutaneous drilling with a cancellous iliac bone graft harvested percutaneously homolaterally. Metaphyseal grafts were excluded from this analysis. Minimum postoperative follow-up was two years. The main outcome was rate of prosthesis conversion at two years.
Results: Considering all stages, 38 hips did not have a total prosthesis at two years (58% success) with a mean follow-up of 40 months (25–65). Twenty-eight hips had total prosthesis at two years (42% failure) with mean follow-up of 11 months (3–23). Mean survival was 29 months (3–65) with stabilisation of the initial lesions in 50% of hips. For the 44 stage II hips, success was achieved in 28 (64%). The success rate for stages IIA and IIB was 70% with mean follow-up of 29 months (19–65). For the 20 stage III hips success was achieved in nine (45%), with 30% for stage IIIB and 54% for stage IIIB and mean follow-up of 21 months (12–45). There were no cases of mechanical complications. One superficial skin infection cured favourably.
Discusssion and conclusion: Subchondral fracture (stage III) and necrosis volume >
30% appear to be unfavourable factors for outcome with this technique. There are other conservative treatments but all with technical difficulties or cost considerations despite sometimes questionable results. This technique is simple and very attractive. In one hand, it combines the advantages of the decompression-effect for the local vascularization with the bone inducer effect of the marrow auto-graft. And in the other, it is a non-invasive and conservative procedure which does not modify the morphology of the upper extremity of the femur and does not jeopardize a future total hip replacement. This is a reliable technique which merits confirmation with a larger series. The best indication remains stage IIA and IIB.