Ali Moradi1, Reza Binava2, Arya Hedjazi3, Saeed Eslami Hasanabadi4, Negar Taher Chaharjouy2, Mohammad Hossein Ebrahimzadeh2. 1. Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran. Electronic address: moradial@mums.ac.ir. 2. Orthopedic Research Center, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran. 3. Legal Medicine Research Center, Legal Medicine Organization, Tehran, Iran. 4. Pharmaceutical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Abstract
INTRODUCTION: To avoid the DRUJ surgical procedures disadvantages, a new intraosseous distal radioulnar prosthesis designed on Sauvé-Kapandji procedure has been introduced. Stability of the prosthesis and biomechanics are to be evaluated in this article. MATERIALS AND METHODS: On a cadaveric study, during placement of the prosthesis, biometry of the bones, prosthesis stability (in axial and lateral tractions, wrist pronation and supination, and squeeze test), wrist range of motion before and after implantation, and radiographic evaluation were done on 16 cadavers. RESULTS: Range of motion of the wrist joint before and after the insertion of the prosthesis, had no significant difference in all six directions. Stability of the prosthesis, when rotational pronation force was exerted, was greater than when rotational supination force was exerted. The prosthesis showed significant stability against longitudinal traction forces in a way that no prosthesis dislocation was observed up to 150 N forces. Stability of the prosthesis was investigated when lateral force was applied to different wrist positions. The most stable position of the prosthesis was in the case of lateral traction forces in supination where no case of dislocation was observed. CONCLUSIONS: The intraosseous distal radioulnar prosthesis demonstrated stable structure with no effect on wrist range of motion. LEVEL OF EVIDENCE: IV.
INTRODUCTION: To avoid the DRUJ surgical procedures disadvantages, a new intraosseous distal radioulnar prosthesis designed on Sauvé-Kapandji procedure has been introduced. Stability of the prosthesis and biomechanics are to be evaluated in this article. MATERIALS AND METHODS: On a cadaveric study, during placement of the prosthesis, biometry of the bones, prosthesis stability (in axial and lateral tractions, wrist pronation and supination, and squeeze test), wrist range of motion before and after implantation, and radiographic evaluation were done on 16 cadavers. RESULTS: Range of motion of the wrist joint before and after the insertion of the prosthesis, had no significant difference in all six directions. Stability of the prosthesis, when rotational pronation force was exerted, was greater than when rotational supination force was exerted. The prosthesis showed significant stability against longitudinal traction forces in a way that no prosthesis dislocation was observed up to 150 N forces. Stability of the prosthesis was investigated when lateral force was applied to different wrist positions. The most stable position of the prosthesis was in the case of lateral traction forces in supination where no case of dislocation was observed. CONCLUSIONS: The intraosseous distal radioulnar prosthesis demonstrated stable structure with no effect on wrist range of motion. LEVEL OF EVIDENCE: IV.