Biomechanical Analysis of Abductor Pollicis Longus Lasso Suspensionplasty for Trapeziectomy

Abstract

Multiple methods of ligament reconstruction and tendon interposition (LRTI) or suspension have been described to prevent first metacarpal subsidence following trapeziectomy. An abductor pollicis longus (APL) lasso is a newly described technique of suspensionplasty, which aims to obviate concerns regarding previously described methods. The purpose of this study was to compare subsidence between the APL lasso and 2 other common methods, APL sling and flexor carpi radialis LRTI, after trapeziectomy in cadaveric forearms. Ten cadaveric forearms were prepared on a custom-made plinth to recreate pinch grip upon the loading of previously identified muscles. A sequence of procedures was performed, with radiographs taken after each to assess the subsidence. The APL lasso was superior to simple trapeziectomy and flexor carpi radialis LRTI in preventing subsidence. The APL lasso was superior to simple trapeziectomy and flexor carpi radialis LRTI in preventing subsidence, and it may be a viable alternative when considering suspension methods after trapeziectomy. The APL lasso may be considered when trying to prevent subsidence after trapeziectomy.