Association between estrogen receptor gene polymorphism and back pain intensity in female patients with degenerative lumbar spondylolisthesis.

STUDY DESIGN: Prospective study. OBJECTIVE: To examine the possible association of estrogen receptor α (ERα) polymorphisms and pain intensity in symptomatic female degenerative spondylolisthesis (DS) patients. SUMMARY OF BACKGROUND DATA: DS has been associated with a significant sex effect. Thus, several studies about the association between the ER gene and osteoarthritis have been reported. However, whether estrogen is associated with pain sensitivity is inconsistent in the existing literatures from both human and animal studies. METHODS: The PvuII and XbaI polymorphisms, bone mineral density at the lumbar spine (LSBMD) and at the femoral neck (FNBMD), pain intensity at the leg and lower back, and radiologic and anthropometric findings were analyzed in 192 patients with DS. RESULTS: There was a significant association between XbaI polymorphism and the visual analog scale score of back pain. The back pain visual analog scale in patients with a GG genotype was significantly higher than in patients with the AG (P<0.05) or the AA (P<0.05) genotypes. In addition, the presence of the CG haplotype was found to be associated with back pain intensity in the haplotype analysis of the PvuII and the XbaI polymorphisms of ERα. CONCLUSIONS: These results suggest that the ERα gene polymorphism using XbaI restriction enzyme influences the perception of back pain in patients with DS.

Posterior approach with posterior soft tissue repair in revision total hip arthroplasty.

We investigated the influence of the posterior approach with soft tissue repair in revision hip arthroplasty by evaluating the rate of early posterior dislocation. Ninety-one patients (96 hips) who had undergone revision hip arthroplasty through the posterior approach were observed for 1 year or until dislocation occurred. Fifty-six revision hip arthroplasties were performed using the posterior approach with soft tissue repair technique. The results of these procedures were compared with those of 40 revision hip arthroplasties that had been performed using the posterior approach without soft tissue repair. The dislocation rate of 10.0% in 40 hips using the posterior approach without soft tissue repair was reduced to 1.9% in 56 hips using the posterior approach with soft tissue repair.

Alterations in the differentiation ability of mesenchymal stem cells in patients with nontraumatic osteonecrosis of the femoral head: comparative analysis according to the risk factor.

It has been suggested that decreased replication capacity of mesenchymal stem cells (MSCs) or decreased MSCs activity in the bone marrow is related to nontraumatic osteonecrosis (ON). However, little is known about differentiation ability of MSCs according to the risk factor of nontraumatic ON. We hypothesize that differentiation abnormalities in MSCs of the bone marrow of the proximal femurs might be related to nontraumatic ON of the femoral head. The purpose of this study was to investigate the osteogenic and adipogenic differentiation ability of MSCs in patients with nontraumatic ON of the femoral head. We examined the differentiation ability of MSCs in cultures derived from the bone marrow of the proximal femurs obtained from 10 patients with hip osteoarthritis (OA) and 37 patients with nontraumatic ON of the femoral head undergoing hip replacement surgery. We analyzed the osteogenic and adipogenic differentiation ability of MSCs according to the risk factor [alcohol-induced (15 patients), idiopathic (12 patients) and steroid-induced (10 patients)] of nontraumatic ON of the femoral head separately and compared it with patients with hip OA. The osteogenic activity was measured as the extracellular matrix calcification by alizarin red S staining and the alkaline phosphatase activity, and the adipogenic activity was measured as the accumulation of Oil red O-positive lipid vacuoles. The osteogenic differentiation ability of MSCs in patients with alcohol-induced and idiopathic ON was significantly reduced compared with that in patients with OA (p < 0.05 and p < 0.05, respectively). In patients with steroid-induced ON, the osteogenic differentiation ability was found to be increased, but the difference was not statistically significant. The adipogenic differentiation ability of MSCs was not significantly changed in patients with alcohol-induced, idiopathic, and steroid-induced ON compared to patients with OA. Our results indicate that altered osteogenic differentiation ability in MSCs is related to nontraumatic ON of the femoral head and the differentiation potential of MSCs in patients with nontraumatic ON differs according to its risk factor.

True femoral anteversion during primary total hip arthroplasty: use of postoperative computed tomography-based sections.

This study investigated a reference line that is closer to the true femoral anteversion on only the cutting surface of the proximal femoral neck during a femoral stem insertion in a cementless total hip arthroplasty. A postoperative computed tomography of both hips from 33 consecutive patients after a unilateral primary cementless total hip arthroplasty with an avascular necrosis of the femoral head was taken to observe the positioning of the stem and its correlation with the true anteversion of the contralateral side. The average of the midcortical angle was 14.1 degrees +/- 6.8 degrees on the lesion side and 0.1 degrees +/- 1.3 degrees more than the true anteversion on the contralateral side. This study has shown that anteversion using a midcortical line between the anterior cortical line and the posterior cortical line is compatible with the true femoral anteversion. However, further investigation is required to confirm the true femoral anteversion.

Decreased osteogenic differentiation of mesenchymal stem cells in alcohol-induced osteonecrosis.

We postulated that osteogenic and adipogenic differentiation ability of the mesenchymal stem cells isolated from the bone marrow could be altered in patients with alcohol-induced osteonecrosis of the femoral head. To examine this hypothesis, we investigated the differentiation ability of the mesenchymal stem cells isolated from the bone marrow from the proximal end of the femur during hip replacements in patients with alcohol-induced osteonecrosis of the femoral head and compared it with the differentiation ability of patients with femoral neck fractures. Marrow was collected from the proximal femurs of 33 patients having hip replacement for either alcohol-induced osteonecrosis of the femoral head or femoral neck fractures. The mesenchymal stem cells were isolated and the culture was expanded from the marrow. The cell populations were compared in terms of the doubling time and the differentiation ability to the osteoblasts and adipocytes. The cells obtained from the patients with alcohol-induced osteonecrosis of the femoral head showed a reduced ability to differentiate the osteogenic lineages compared with the cells obtained from the patients with femoral neck fractures. Such changes may play a role in the development of alcohol-induced osteonecrosis of the femoral head. The altered function of mesenchymal stem cells can be responsible for the pathogenesis of osteonecrosis.