RESUMO
BACKGROUND: A process of -80 ℃ profound hypothermia over three months and freeze drying will suppress the histocompatibility antigen of decalcified freeze-dried bone and reduce their immunogenicity. OBJECTIVE: To investigate the effect of treating intraarticular fracture using allogeneic decalcified freeze-dried bone nail alone. DESIGN, TIME AND SETTING: From August 2000 to August 2007, a clinical analysis was performed among 83 patients of cancellous bone fracture involving articulus, who were enrolled from Department of Orthopaedics in the Central People's Hospital of Zhanjiang (Zhanjiang, Guangdong, China). MATERIALS: The involved patients consisted of 64 males and 19 females, aged 16-53 years with a mean of 36.3. The lesioned sites were elbow joint in 28 cases, acetabulum in 6 cases, femoral condyles in 9 cases, tibial plateau in 17 cases and ankle joint in 23 cases. Allogeneic decalcified freeze-dried bone nail was developed by the Biomaterial Laboratory of the Southern Medical University (also known as the First Medical University of Chinese PLA). METHODS: Totally 83 cases of cancellous bone fracture involving articulus were fixed with bone nail or bone screw after reducing of bone fracture. Bone nails or screws were pretreated with saline or allogeneic blood over 30 minutes. Bone nail at 3.5-mm diameter were applied on elbow joints and ankle joints, while those at 4.0-mm diameter for knee joints and hip joints. After implantation, hip and femoral condyles fractures were treated with the traction for 4-6 weeks, and the fractures of elbow joints, ankle joints and tibial plateau were fixed with gypsum for 4-6 weeks. Patients received functional exercise after wound healing. Subsequent to draining for 48 hours, antibiotics were used to prevent infection, but immune depressant was unnecessary. MAIN OUTCOME MEASURES: Wound healing was observed. The growth of osteotylus and the absorption of bone nail were checked with X-ray. Immunological rejection was also checked. RESULTS: One case had dystopia at postoperative 2 weeks, one case with breakage of bone nail was found at postoperative 3 weeks, and two cases developed immunological rejection in advanced stage. The other 79 cases got bone healing without dystopia or immunological rejection, and they achieved bone union within 1-3 months with normal joint function. CONCLUSION: Being internal fixation material of intraarticular fracture, allogeneic bone nail can maintain the stabilization of cancellous bone fracture to bone healing, exhibit complete absorption and be good at bone repair.