半骨盆截肢后用废弃自体骨重建骨盆承重功能的解剖学与生物力学研究

目的 探讨对骨盆肿瘤行半骨盆截肢后,应用废弃自体骨重建坐骨结节和骨盆环以恢复骨盆承重功能的可行性.方法 带双侧下肢骨的10具骨盆标本,测量坐骨结节至正中矢状面和经骶骨耳状面中心冠状面的垂直距离、坐骨结节至同侧的骶骨耳状面和耻骨联合的距离.测量股骨髁和胫骨平台的最大径,对股骨和胫骨进行CT扫描并纵向剖开,观察骨质分布情况.根据解剖测量结果,选择4具成人尸体标本,应用电子万能试验机对完整骨盆和重建标本进行生物力学检测,比较两者在0-500 N的垂直加压下的稳定性.结果 坐骨结节至正中矢状面和经耳状面中心至冠状面的垂直距离分别为(4.52±0.48)cm和(3.31±0.57)cm.坐骨结节至同侧骶骨耳状面和耻骨联合的距离分别为(11.75±6.19)cm和(15.72±5.19)cm.股骨髁最大斜径在外后至内前方向平均为(7.93±0.44)cm,胫骨平台的最大径在冠状面上,平均为(7.19±0.61)cm.股骨髁和胫骨平台主要为松质骨,股骨髁松质骨平均纵向长度为(6.24±0.22)cm,胫骨上端平均纵向长度为(5.64±0.18)cm.在生物力学试验中,重建骨盆的抗压缩能力较完整骨盆弱,但在载荷去除后,重建骨盆和完整骨盆均可恢复原来的状态,说明重建骨盆和完整骨盆同样为弹性良好的刚体结构,具有较好的即刻稳定性.结论 半骨盆截肢后,可应用废弃股骨或胫骨重建坐骨结节和骨盆环,为患者坐立和装配假肢提供力学支持点,以降低半骨盆截肢者的残废程度.

Anatomic and biomechanical study of the reconstructed pelvis with autograft after hindquarter amputation

Objective To determine the possibility of restoring the weight bearing function of pelvis with autograft after hindquarter amputation.Methotis 10 pelves specimens with lower extremities involved in this study.To measure the perpendicular distance from ischial tuberosity to median sagittal plane and coronal plane through auricular surface center on 10 pelves.the distance from ischial tuberosity to ipsilateral facies auricularis and symphysis pubis,and the maximum oblique diameter of femoral condyle and tibia plateau.CT scan and cross section cut were performed to find the distribution of cancellous bone in distal femur and proximal tibia.Biomechanical study Was carried out on 4 intact and reconstructed pelves to compare their stability under the axial loading in the gradient from 0 to 500 N.Results The perpendicular distance from ischial tuberosity to median sagittal plane and coronal plane through auricular surface center were (4.52±0.48)ca and(3.3 1±0.57)cm respectively.The average distance from ischial tuberosity to ipsilateral facies auricularis and symphysis pubis were(11.75±6.19)cm and(15.72±5.19)cm respectively.The maximum oblique diameter of femoral condyle was situated from postemlateral to anteromedia direction.with mean length of (7.93±0.44)cm.,The maximum oblique diameter of tibial plateau lies on the coronal plane,with average length of(7.19±0.61)cm.The femoral condyle and tibial plateau were mainly occupied by cancellous bone.The average thickness of cancellated bone in femoral condyle and tibial plateau were (6.24:0.22)cm and(5.64±0.18)cm respectively.Biomechanical experiment showed the resisting compression ca pability of reconstructed pelvis Was weaker than that of intact one,but the instant stability of two models was similar.Conclusion It is feasible to reconstruct the ischial tuberosity in situ and pelvic ring with an individual femur or tibia to provide mechanical supporting point in sitting,standing and fitting prosthesis of pa tients after hindquarter amputation and decrease their handicapability degrees.