Abstract
ONFH with large or lateral-located lesion is challenging due to difficulty of regeneration. We introduce novel tissue engineering technique using ex vivo expanded bone marrow stromal cell seeded on calcium metaphosphate (CMP) scaffold to regenerate dead bone for these challenging cases. Ten millilitres of bone marrow was aspirated from iliac crest and mononuclear cells were collected. These cells were expanded and differentiated to osteoblast-lineage cells using osteogenic media and autologous serum for 2–4 weeks ex vivo. Porous bead-form scaffolds were made of CMP and cells were seeded in a density of million/ml³ into 20 to 30 beads for 1 hour. The necrotic area was curetted and the beads were implanted through core tract in 9 hips (Steinberg IIc in 5 hips and IVc in 4 hips which involved greater than 30% of whole head; JIC classification C1 in 4 hips, and C2 in 5 hips which involved weight bearing area). The tract was blocked with a CMP rod. The age of patients ranged from 16 to 37. Associated factors were; steroid in 4, idiopathic in 3, alcoholic in 1 and traumatic in 1 hip, respectively. Kerboul combined necrotic angle was more than 200° in all hips. We compared preoperative and annual radiographs and MRI images to check dome depression of femoral head and signal change of osteonecrotic area. Follow-up period ranged from 8 to 14 years. Two IIc lesions progressed and were converted to THA at two and six years postoperatively. We could get clinical and radiographic success in 7 hips (78%). Follow-up radiographs and MRI showed partial or nearly complete regeneration of necrotic bone, prevention of collapse, and reduction in necrotic lesion. This can be a good strategy for bone regeneration of unmet need as in a human model.
