Abstract
Aims: Does PHILOS (Proximal Humeral Internal Locking system) construct provides better þxation than Clover leaf plate and T-plate in a simulated 2-part fracture of proximal humerus, in an osteoporotic bone model?Materials and Methods: Biomechanical laboratory study. Third generation composite Humerus model was used, with short e-glass epoxy þbres forming cortex and polyurethane cancellous core. Low density polyure-thane core (1.2gm/cc) was used to simulate an osteoporotic model. Osteotomy at surgical neck of humerus was carried out to create 2-part fracture of proximal humerus. Samples were randomised to receive one of the implants. Following þxation samples were placed in a custom made jig to þx proximal and distal ends without interfering with implants and osteotomy site. All samples were subjected to cyclical torque, Torque to failure, Cyclical compression and Compression loading to failure. Results were entered in a database. Results: PHILOS provided signiþcantly better þxation in ÔTorque to failureñ experiment. PHILOS construct shows less plastic deformation in cyclical torque and cyclical compression. Locking screws did not Ôback offñ in any of the experiments involving PHILOS construct, however ordinary screws did back off both in Ôtoque and compressionñ testing. Conclusions: PHILOS construct provides better stability in Torque and compression as compared to conventional plating devices, in an osteoporotic bone model.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
