Biomechanical study on the injury of the terminal extensor apparatus
LIU Zhigang ,WANG Guojun,YU Jiaao. Department of Hand Surgery, the First Hospital of Jilin University, Changchun 130021, China
Objective To discuss the machanism of the mallet finger caused by the injury of the terminal apparatus from the viewpoint of biomechanics. Methods The tensile extension and crush experiment were done on the index fingers,the long fingers,the ring fingers and the little fingers from the fresh Chinese normal cadavers in 10 cases and the results were analysized by the biomechanical methods.Results We got the kinetic and tensile strength relation figure on the tensile extension experiment and indicated the middle part of the terminal extensor apparatus was the strength dangerous area.The crush experiment demonstrated that the terminal extersor apparatus had the dependancy on the speed:the strength of the terminal extensor apparatus was less than that of bone under the fast load, which made the rupture of the extensor tendon;the strength of the terminal extensor apparatus was greater than that of bone under the slow load,which led to the exersion fracture of the bone.Conclusions The machanisms of the mallet finger were different in the tendon rapture induced and bone fracture induced mallet fingers,the treatment methods were also different principally.
【CateGory Index】： R658.1