Bone Marrow Injection in Hip Osteonecrosis

Several techniques have been described for supplementing core decompression with bone grafts and other materials. In this technique, grafting is done with autologous bone marrow obtained from the iliac crest of patients operated for hip osteonecrosis. The bone marrow is harvested under general anesthesia. A beveled metal trocar of 6 to 8 cm length and a bore of 1.5 mm is pushed deep into the cancellous bone. A 10-mL syringe that has been flushed with heparin is used to aspirate the marrow. Once the needle has been inserted to the desired depth, the tip is swept around a full circle in 45 degrees steps, with the bevel pointing in different directions at each step. This procedure is continued until a sufficient quantity of bone marrow has been harvested (150 mL). All the marrow aspirated is discharged into a plastic collection bag containing anticoagulant solution. It is then filtered to remove fat aggregates and clots. The aspirated marrow is reduced in volume by concentration and injected in the femoral head after core decompression with a small trocar. To measure the number of progenitor cells transplanted, the fibroblast colony forming unit is used as an indicator of the stroma cell activity and performed in vitro cultures of the fibroblast progenitor cells. The bone marrow is injected into the femoral head using a small trephine (Mazabraud, Collin, France). The instrument is introduced through the greater trochanter, as in conventional core decompression. Its position in the femoral head and in the necrotic segment is monitored with fluoroscopy. Because of the plain radiography evidence of necrosis at the time of treatment, preoperative MRI scans should be used together with the image intensifier to determine the site of the lesion. The bone marrow is injected through the trephine into the necrotic zone. When patients were operated on before collapse (stage I and stage II), hip replacement was done in 9 of the 145 hips. Total hip arthroplasty was necessary in 25 of the 44 hips operated on after collapse (stage III and stage IV). According to our experience, the best indications are hips with osteonecrosis and without collapse. In some patients who had Steinberg stage III (subchondral crescent, no collapse), successful outcomes (no further surgery) have been obtained between 5 and 10 years. Therefore, in selected patients, even more advanced disease can be considered for this technique.