Bone loss and bone turnover in acute and chronic spinal cord injured patients

Objectives: To investigate bone loss and the rate of boneturnover in individuals with spinal cord injury (SCI), andto compare the results with those healthy controls.Methods: This cross-sectional, controlled study wasperformed between January and December 2005, in theIstanbul Physical Medicine and Rehabilitation TrainingHospital, Istanbul, Turkey. Forty-eight patients with SCIwere included in the study. The control group consistedof 47 age and sex matched healthy subjects. Bone densitywas measured at the proximal hip region by dual-energyX-ray absorptiometry. Serum levels of osteocalcin (OC)and C telopeptide of type 1 collagen (CTX) weremeasured.Results: Femur neck and femur total bone mineraldensity values in the SCI patients and control group were0.894 (0.188), 0.911 (0.185), and 0.994 (0.116), 1.063(0.132) (p 0.03, p 0.000). Serum levels of OC andCTX were significantly increased in patients (p 0.015,p 0.000). Femur bone density in both neck and totalregions showed a significant decrease in the SCI patientswith longer injury duration (p 0.001, p 0.000). SerumCTX levels were markedly elevated in the first year ofSCI. However, serum OC level showed no difference forthe injury duration.Conclusion: Significant bone loss was found at theproximal hip in SCI patients. Serum biochemical markerswere also significantly higher in the patient group thanthe healthy controls. The bone density was lower in thelong-standing SCI patients, although serum CTX levelswere higher in the first 12 months after injury.