同种异体骨移植后的病理组织学观察

An pathological observation of retrieved human allografts

目的探讨同种异体骨移植后骨修复的生物学过程和病理组织学变化。方法收集自2002年2月～2004年3月因临床并发症取出的异体骨标本5例及因大段异体骨移植后不愈合再次植骨手术中活检病例2例,共7例。骨肿瘤4例,其中肱骨近端恶性纤维组织细胞瘤行肿瘤切除大段异体骨移植髓内钉内固定术1例,股骨干骨肉瘤行肿瘤段切除大段异体骨移植1例,股骨远端骨巨细胞瘤行肿瘤切除股骨远端大段异体骨移植钢板内固定术1例,胫骨近端巨细胞瘤行肿瘤切除大段异体骨移植钢板内固定术1例。创伤3例,其中2例为左股骨远端开放粉碎性骨折行大段异体骨移植骨不愈合切开取内固定植骨、外固定架固定术,同时对大段异体皮质骨取材活检;1例为胫骨中段开放性骨折,行钢板固定异体松质骨移植术,术后感染。结果通过观察骨吸收的病理组织学特点发现骨吸收主要集中在5例病例中,其临床特点可以归纳为:(1)X线片所示有严重的骨吸收,无伤口问题;(2)X线片显示有骨吸收伴有窦道、渗出;(3)伤口化脓。后者可以认为是骨组织的化脓性感染引起的骨吸收,前两种情况骨吸收可以分为:一是破骨细胞性骨吸收,常伴有新骨形成;二是炎症性骨吸收,吸收部位有较多的慢性炎性细胞,骨表面缺乏破骨细胞和成骨细胞,无新骨形成。3例有明显骨吸收者可以观察到血管内皮细胞增生?

Objective To study the retrieved human allografts pathologically in order to probe into the histological changes of implanted allograft. Methods The specimens were retrieved from seven cases between February 2003 and March 2004, and the allografts had been in situ from two to 16 months. Of seven cases, four were diagnosed primarily as malignant fibrohistocytoma of proximal humerus, osteosarcoma of femoral shaft, bone giant cell tumor of distal femur and bone giant cell tumor of proximal tibia each, which were treated with wide resection of tumor and massive allograft transplantation and internal fixation of plate or inter-locking nail; two were open comminuted fracture of distal femur, treated with massive allograft transplantation and internal fixation, underwent autograft bone transplantation because of united massive allograft, had a punch biopsy of allografts for observation; one was tibial open fracture being fixated with inter-locking nail and small segment allograft transplantation, sustained infection at two weeks after primary operation and underwent debriment, removal of internal fixation and external fixation. Results Of seven cases, five were found with bone absorption radiographically, and were classified into three types:1)sever bone absorption; 2)bone absorption associated with sinus and effusion of the wound; 3)bone absorption accompanied by pyogenic infection. The later condition was caused by bacterial infection without a relationship of allograft. And the former two conditions could be classified into two subtypes: 1)osteoclastic absorption, which was followed by new bone formation; 2)inflammatory absorption, which was found with infiltration by round inflammatory cell, preponderantly lymphocytes, and mononuclear phagocytes with few osteoclasts, osteoblasts or new bone formations. Moreover, in sever bone absorption, vascular lesions such as vasculitis, swelling of endothelial cells or proliferation changes in the vessels, and obliteration of the arteries. Conclusion An intensive infiltration accompanied by vascular lesions may be the evidences of histological changes suggestive of an immune reaction directed against the grafts, and the failure of the clinical outcomes.