In Vitro Stability Analysis of the Trapeziometacarpal Joint Implants

  • 鄧 經弘

Student thesis: Master's Thesis

Abstract

Human hands have a unique opposition movement that allow the performance of dexterous and complex motions These movements are enabled by the Trapeziometacarpal (TMC) joint of the thumb The TMC joint has two mutually saddle-like articular surfaces and is constrained by 16 supporting ligaments which limit the range of motion The TMC joint is flat enough for bearing large axial forces and the curvature is sufficient to avoid subluxation to perform more powerful strength than other joint can In addition flatter joint curvature surface can deal with larger axial loads but may cause instability during movement Six fresh frozen cadaver hands were used for total joint arthroplasty in this study The prostheses contained three different saddle type curvature implants and one ball-and socket type implant The electromagnetic tracking device was used to record real-time movement when guiding the thumb movements The passive motion was first guided by using the manual-control to the maximum end range for four directions upward-downward and inward-outward also the circumduction of the thumb Nest the simulator was set at the same movement as the manual-control with movement trajectory calculated from manual control When the intact data were recorded specimens would have the joint arthroplasty surgery for replacing the articular surface and repeated the tests The results showed the ROM of the TMC joint decreased 23 08 % 4 60 % and 14 39 % on original curvature greater curvature and ball-and socket implant but increase 35 40 % in prostheses with lower curvature comparison with intact condition in the average The original curvature shifted the path of the first metacarpal articular surface center to radial-volar side on the articular surface of trapezium bone but the two different curvature implants and ball-and-socket prostheses shifted to ulnar-volar and volar-distal side The displacement of the path increased 9 90 % 7 07 % and 69 75 % on original curvature greater curvature and lower curvature but decreased 26 99 % on ball-and socket type comparison with intact condition in the average Implants with greater curvature provide greater stability but limit range of motion and joint displacement However the ball-and-socket type implant provide greater joint stability than saddle type implants
Date of Award2014 Aug 13
LanguageEnglish
SupervisorFong-chin Su (Supervisor)

Cite this

In Vitro Stability Analysis of the Trapeziometacarpal Joint Implants
經弘, 鄧. (Author). 2014 Aug 13

Student thesis: Master's Thesis