Bone mineral density differences between paraplegic and quadriplegic patients: a cross-sectional study

Study design: This cross-sectional study was conducted by comparing bone mi neral density (BMD) of paraplegic and quadriplegic patients. Objectives: The purpose of this study was to investigate the relationship b etween the bone mineral loss and injury level in spinal cord injury patient s. Settings: Experiments were conducted at Yoneda Hospital and Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan. Methods: Lumbar spine (L2-4), proximal femur (femoral neck, trochanter regi on and Ward's triangle) and whole body BMD were measured in ten paraplegic and ten quadriplegic patients using dual-energy X-ray absorptiometry (DXA, HITACHI BMD-1X). Results: Significant differences were observed in the lumbar spine, trochan ter region and upper extremities BMD between paraplegic and quadriplegic pa tients (P<0.05, P<0.05 and P<0.01, respectively), but not in the femoral ne ck, Ward's triangle, head, pelvis, lower extremities or whole body BMD. Conclusion: These results suggest that the injury level influences on the l umbar spine, upper extremities and trochanter region BMD. From a biomechani cal standpoint, it is possible to explain that the differences in mechanica l loading exerted on bones also affected the difference of lumbar spine BMD in the two groups.