Extensor carpi radialis brevis transfer to extensor pollicis longus: an anatomical study

Abstract

Objective To investigate the anatomical basic of extensor carpi radialis brevis (ECRB) tendon trans-ferring to extensor pollicis longus (EPL) tendon. Methods Twelve sides of ECRB and EPL in fresh adult cadaver’s forearms were collected, and the anatomical model of ECRB transferring to EPL was set up in all the forearms. The ana-tomical parameters of EPL were measured before and after anatomical model established. Results The effective trans-ferring length of ECRB was (3.5±0.8) cm; the maximum circumferential of ECRB and EPL were (8.5±0.8) cm and (3.6±0.3) cm (P >0.05) , the ratio of muscle cross-sectional area was 5.57; After the anatomical model setting up, anatomic an-gles of EPL was (30±7) °, which was a decrease of (20±5) ° comparing with the preoperative angel of (50±9) ° (P >0.05) ; Thumb extension angle was (50±12) °, which was a decrease of (8±3) ° comparing with the preoperative angel of (58 ±16) ° (P 0.05) ; Thumb tip lifting height was (2.3±0.9) cm, which was a decrease of (1.2±0.6) cm comparing with the preoperative height (3.5±1.2) cm (P >0.05). Conclusion Based on the measurement of the anatomic parameters of ECRB and EPL, the ECRB has enough length and muscle force to reconstruct the function of EPL. The thumb had a good extension appearance and accorded with the rule of biomechanics after setting up the anatom-ical model of ECRB transferring to EPL. This study will provide the anatomical evidence for further clinical application Key words: Extensor carpi radialis brevis; Extensor pollicis longus; Tendon transfer; Applied anatomy