Objective：To assess the effects of immobilization on the three-dimensional microstructure of cortical and cancellous bone.

Methods：Eight-week-old specific-pathogen-free Wistar rats were divided into two groups：the control (n＝12) and immobilized group (n＝12). The hind limbs of the rats in the immobilized group were fixed using orthopedic casts for 4 weeks. The cortical bone at the mid-shaft and the cancellous bone at the distal metaphysis of the femur were analyzed using micro-computed tomography.

Results：The values of total cross-sectional area, cortical bone area, and cortical thickness in the immobilized group were significantly lower than those in the control group. Meanwhile, the relative bone volume (bone volume/total volume) and mean trabecular thickness in the immobilized group decreased and the structure model index significantly increased compared with the values in the control group (P＜0.05).

Conclusion：Our rat model can evaluate the effects of load-permitting immobilization. The results of this study indicate that structural changes in immobilized osteopenia-affected bone arise mainly from thinning of the cortex and reduction of cancellous bone volume caused by a reduction of trabecular width.

Spinal tuberculosis usually occurs in a single vertebral body or two to three adjacent vertebrae; it rarely occurs in multiple vertebral bodies. Surgery is indicated in cases that do not improve with conservative therapy, or when paralysis is evident. Two cases regarding patients with spinal tuberculosis in multiple vertebral bodies on whom surgery was performed are reported. Case 1, the patient was a 77-year-old woman with spinal tuberculosis in four vertebral bodies from the lower thoracic to the lumbar spine. As she had pronounced lower back pain, posterolateral fusion with a pedicle screw was performed. Case 2, the patient was a 29-year-old Indonesian man with spinal tuberculosis in 17 vertebral bodies of the spine who was unable to stand due to paralysis of both legs, thus posterolateral fusion with a pedicle screw was performed. Good results were obtained from tuberculostatic drug therapy and surgical instrumentation.
Adult ; Aged ; Antitubercular Agents ; Female ; Humans ; Low Back Pain ; male ; Paraplegia ; Spine ; Surgical Instruments ; Tuberculosis ; Tuberculosis, Spinal