Patricia O Rappaport1, Andrew R Thoreson1, Tai-Hua Yang1, Ramona L Reisdorf1, Stephen M Rappaport2, Kai-Nan An1, Peter C Amadio3. 1. Tendon and Soft Tissue Biology Laboratory and the Biomechanics Laboratory, Mayo Clinic, Rochester, MN, USA. 2. School of Public Health, University of California, Berkeley, Berkeley, CA, USA. 3. Tendon and Soft Tissue Biology Laboratory and the Biomechanics Laboratory, Mayo Clinic, Rochester, MN, USA. Electronic address: pamadio@mayo.edu.
Abstract
INTRODUCTION: Therapy after flexor pollicis longus (FPL) repair typically mimics finger flexor management, but this ignores anatomic and biomechanical features unique to the FPL. PURPOSE OF THE STUDY: We measured FPL tendon tension in zone T2 to identify biomechanically appropriate exercises for mobilizing the FPL. METHODS: Eight human cadaver hands were studied to identify motions that generated enough force to achieve FPL movement without exceeding hypothetical suture strength. RESULTS: With the carpometacarpal and metacarpophalangeal joints blocked, appropriate forces were produced for both passive interphalangeal (IP) motion with 30° wrist extension and simulated active IP flexion from 0° to 35° with the wrist in the neutral position. DISCUSSION: This work provides a biomechanical basis for safely and effectively mobilizing the zone T2 FPL tendon. CONCLUSION: Our cadaver study suggests that it is safe and effective to perform early passive and active exercise to an isolated IP joint. LEVEL OF EVIDENCE: NA.
INTRODUCTION: Therapy after flexor pollicis longus (FPL) repair typically mimics finger flexor management, but this ignores anatomic and biomechanical features unique to the FPL. PURPOSE OF THE STUDY: We measured FPL tendon tension in zone T2 to identify biomechanically appropriate exercises for mobilizing the FPL. METHODS: Eight human cadaver hands were studied to identify motions that generated enough force to achieve FPL movement without exceeding hypothetical suture strength. RESULTS: With the carpometacarpal and metacarpophalangeal joints blocked, appropriate forces were produced for both passive interphalangeal (IP) motion with 30° wrist extension and simulated active IP flexion from 0° to 35° with the wrist in the neutral position. DISCUSSION: This work provides a biomechanical basis for safely and effectively mobilizing the zone T2 FPL tendon. CONCLUSION: Our cadaver study suggests that it is safe and effective to perform early passive and active exercise to an isolated IP joint. LEVEL OF EVIDENCE: NA.