AbstractThe implantation of combined hydroxyapatite (HAP) and autogenous red bone marrow (BM) was used to repair bone defect resulting from fibrodysplasia of bone in one case. After one year, the specimen was studied under optical and electronic scanning microscopes in order to study the biological features, histological changes and osteogenesis of hydroxyapatite implanted in the body. The results showed that there was not any inflammatory, toxic, or immune reaction in the tissue surrounding HAP-BM, and that HAP implanted was almost completely replaced by newly formed bone, and was firmly united to the surrounding bony tissue. This indicated that in the body HAP had a good biocompatibility and that HAP-BM provided the scaffold for osseous ingrowth as wellas boneinduction substances. The whole result was to that of the autogenous bone graft.
In order to evaluate the long-term effect of total hip replacement (THR) in patients with steroid-induced femoral head necrosis, 40 cases of 50 hips received THR patients were followed up for an average of 8.5 years after operation. Evaluation was carried act according to Harris score system. In these cases, average score was seventy-five points. Revision rate among them was 2% after four years and 18% after five to eight and a half years, with as overall rate of 20%. It was found that the main reason for revision was looseness of the prosthesis. In this follow-up, it showed that besides foreigen body reaction, abnormal osseous remodelling was the main factor in long-term failure of this arthroplasty. It was also proved that it was a good selection to perform cemented total hip replacement in younger patients, which could improve living quality.
OBJECTIVE: To investigate the effect of intermittent pneumatic compression on prevention of deep venous thrombosis after operation of lower limbs. METHODS: From Oct. 1997 to Aug. 1998, forty cases were received Doppler examination preoperatively, which showed no deep venous thrombosis in all the lower limbs of 40 cases. Among them, 24 cases were received total hip arthroplasties, 4 cases were received total knee arthroplasties and 12 cases were received dynamic hip screw. Postoperatively, every case were continuously received intermittent pneumatic compression for 14 to 21 days (2 hours, qid), and venography were performed on the operated lower limb on the 7th day after operation to check the presence of deep venous thrombosis. RESULTS: Among the 40 cases, there were 4 cases of deep venous thrombosis without symptom of pulmonary embolism, the incidence rate was 10%. CONCLUSION: Intermittent pneumatic compression can significantly reduce the incidence rate of deep venous thrombosis after the operation of the lower limbs.