发育性髋关节脱位患儿术后股骨骨密度的变化及临床意义

Clinical significance and changes of femoral bone mineral density in children with developmental dislocation of hip

目的 研究发育性髋关节脱位患儿手术前后股骨骨密度的变化,讨论术后患儿发生骨折的可能性及如何减少骨折的发生.方法 采用美国Norland XR46骨密度扫描仪,以双能X线吸收法测定92例发育性髋关节脱位患儿在手术前及术后2、4、6个月的双侧股骨骨密度.同时测定15名健康儿童骨密度值,作为对照.结果 术前手术组与对照组的股骨骨密度无明显差异,手术组患儿双侧股骨骨密度无明显差异.92例患儿术后2个月手术侧股骨骨密度均明显下降（平均值自0.5178±0.0829降至0.2878±0.0674）,至术后6个月出现不同程度的恢复（平均值恢复至0.4927±0.1073）.结论 接受髋关节切开复位手术患儿,术侧股骨骨密度在术后2个月内出现明显降低,拆除石膏后逐渐恢复,术后6个月股骨骨密度仍明显低于正常,此期间为功能锻炼期,易发骨折.

Objective To analyze the risks and treatments of post-operative fracture by assessing the femoral bone mineral density in the children with developmental dislocation of hip. Methods The Norland XR46 bone densitomer system （USA） was employed and dual X-ray absorptiometry was employed to measure the bilateral femoral density of 92 children with developmental dislocation of hip pre-operatively and,2,4 and 6 months post-operatively. Results All 92 children demonstrated significant femoral bone mineral density reduction on the operated side 2 months posts-operatively （from 0. 5178 ± 0. 0829 to 0. 2878 ± 0. 0674）. They recovered to different degree after 4 months after removing plaster and internal fixation plate （the average recoved to 0. 4927 ± 0. 1073）. Conclusions The mineral density of the femur in children who underwent operative reduction for developmental dislocation of the hip joint decreased significantly 2 months post-operatively. It recoverd after the removal of the plaster. The femoral bone density during this period was lower than normal and it is susceptible to fracture.