Abstract
Introduction
This study reports the results of percutaneous autologous bone marrow grafting in 62 patients with corticosteroids treatment who had one hip osteonecrosis treated with bone marrow (BM) injection and the other contralateral hip osteonecrosis with core decompression (CD) alone. Only patients with bilateral symptomatic osteonecrosis and with those hips at stage I or II (as defined by Steinberg) were included in this study.
Material and Methods
Between 1988 and 1995, 62 consecutive patients (28 males and 34 females) were included in this study. These patients had a mean age of 31 years (range 18 to 34 years) at the time of the onset of symptoms. The average follow-up was 17 years (range, 15 to 20 years). An average of 152 + 16 milliliters of marrow was aspirated from the iliac crest. The number of stroma progenitor that was transplanted was estimated by counting the Fibroblast Colony Forming Units which express type I and type III collagen. The bone marrow graft obtained after concentration contained average 4889 + 716 progenitors per cubic centimeter (range 3515 to 6293 per cubic centimeter). Each hip received a mean number of thirty cubic centimeters of bone marrow graft (range 27 to 35 cubic centimeters). The average total number of CFU-F injected in each hip was therefore 147 × 103 cells (range 119 × 103 to 195 × 103 cells).
Results
Clinical results were determined by the change in Harris hip scores from preoperative evaluation to the last follow-up visit, by the change in the radiographic progression and by the need of subsequent total hip arthroplasty. Bone marrow grafting afforded better reduction in pain, effected a reduction with time in the number of hips that progressed to collapse, and delayed the need for total hip replacement. Ten hips had collapsed and needed arthroplasty at the most recent follow-up after bone marrow grafting, compared to 45 after core decompression. For hips with collapse, the mean survival time before collapse was 71.2 months (43.35- 60.96; 95% CI) for the bone marrow graft group and 38.5 months for the control group (13.2–39.74; 95% CI). With the number available, there was a positive correlation (Spearman's test) between the duration of clinical survival before collapse and the number or concentration of CFU-F and CFU-GM in the graft in the CD group. These results are explained by the fact that bone marrow injection improved the repair process on MRI and on histology. Overall, 10 hips with bone marrow injection showed a total regression of the signal, 59 hips showed a partial reduction (42 with BM and 17 with CD) and 55 hips did not show a significant reduction (10 with BM and 45 with CD).
Conclusion
Bone marrow grafting afforded better reduction in pain, reduction in the number of collapses, delayed the need for total hip replacement, and improved the repair process on MRI and on histology.
