Abstract
Symptomatic and non-symptomatic hip osteonecrosis related to sickle cell disease (SCD) has a high risk of progression to collapse and total hip arthroplasty (THA) in this disease has a high rate of complications. We asked question about the benefit of performing an IRM to detect and treat with cell therapy an early (stage I or II) contralateral osteonecrosis.
430 consecutive SCD adult (32 years, 18 to 51) patients (225 males) with bilateral osteonecrosis (diagnosed with MRI) were included in this study from 1990 to 2010. One side with collapse was treated with THA and the contralateral without collapse (stage I or II) treated with cell therapy. The volume of osteonecrosis was measured with MRI. For cell therapy, the average total number of mesenchymal stem cells (MSCs) counted as number of colony forming units-fibroblast injected in each hip was 160,000 ± 45,000 cells (range 75,000 to 210,000 cells).
At the most recent FU (20 years, range 10 to 30), among the 430 hips treated with cell therapy, 45 hips (10.5%) had collapsed and had required THA at 10 years (range 5 to 14 years) and 380 hips (88%) were without collapse and asymptomatic (or with few symptoms) with a decrease percentage of necrosis on MRI from 45% to 11%. Among the 430 contralateral THA, 96 (22.3%) had required one revision, 28 had a re-revision, and 12 a third re-revision with aseptic loosening (85% of revisions) and/or infection (6% of revisions). Hips undergoing cell therapy were approximately three times less likely to undergo revision or re-revision surgery (p < 0.01) as compared with hips undergoing a primary THA.
THA is the usual treatment of collapsed ON in patients with SCD. In this population, it is worth looking with MRI for an early stage on the contralateral hip and performing (when necessary) bone marrow cell implantation during the same anesthesia as for arthroplasty.