Biomechanical study of injectable calcium phosphate cement in repairing lateral tibial plateau compression fractures in goats

Abstract

Objective To make a comparison of mechanical stability between calcium phosphate cement(CPC)and autograft in repairing lateral tibial plateau compression fractures in goats. Methods Bilateral tibial plateau compression fractures were made in 10 hind legs of goats.The bilateral fractures were reduced and filled with CPC and autograft respectively.Animals were executed 3 and 6 months after operation. Their bilateral tibial plateaus were obtained and the articular sudace subsidence of the plateaus was evaluated. Cement absorption was observed by X-ray examination and tibial plateau compression rigidity was tested. Articular Burface histology was evaluated with non-decalcified sections. Results Slight articular subsi- dence occurred in 3 of the 10 CPC specimens,while mediate or serious subsidence occurred in 8 of the 10 autograft specimens.X-ray showed that CPC was absorbed into several small blocs in 3 months and nearly disappeared in 6 months.Anti-compression rigidity was 226.89 ±62.81 N/mm in CPC group and 172.97 ± 79.82 N/mm in autngraft group in 3 months(t=1.369,P=0.243),and 471.27±212.89 N/nun and 371.05±207.98 N/mm in 6 months(t=0.948,P=0.397)respectively.There was no significant dif- ference between groups.Histology study showed plenty fibrous tissues existed in the repaired cartilage in au- tograft group,while fibrous tissues were scanty in the repaired cartilage in CPC group.Conclusions CPC can provide better eady fixation intensity than autograft in repairing tibial plateau compression fractures.CPC can be absorbed rapidly in hrge animals. Key words: Goat; Tibial fracture; Biomechanics; Calcium phosphate cement(CPC)