Evaluation of bone mineral density and morphology using pQCT in children after spinal cord injury.

OBJECTIVE

To evaluate the effects of spinal cord injury (SCI) on bone density and morphology in children using peripheral quantitative computer tomography (pQCT).

DESIGN

Retrospective cohort study of 19 paediatric patients with SCI (9 paraplegics and 10 tetraplegics).

RESULTS

There was significant reduction in tibial metaphysial volumetric bone mineral density (vBMD), diaphysial cortical cross-sectional area (CSA), cortical thickness and polar strength-strain index. There was a significant loss of calf muscle CSA. Those who were able to stand had greater trabecular vBMD, tibial cortical thickness and tibial muscle CSA Z-scores. Lower limb fractures did not occur if tibial trabecular vBMD was greater than 100 mg/cm³. Tibial geometry following SCI was more circular compared to controls.

CONCLUSIONS

pQCT provides a valuable insight into the regional changes in bone and muscle development in children following SCI. Residual muscle function with the ability to weight bear provides a significant benefit to bone development.