Content area
Abstract
Purpose
The lacertus fibrosus (LF) is involved in various surgeries. However, the biomechanical contribution of the LF remains unclear. The aim of this study was to determine the role of the lacertus fibrosus on the elbow and forearm kinematics and on the biceps brachii muscle lever arms.
Methods
This biomechanical study was performed on seven fresh-frozen upper limbs of cadavers. Elbow flexion, forearm supination, and biceps brachii muscle lever arms were analyzed in the intact conditions (I) and after superficial (R) and deep part (R2) of the lacertus fibrosus release, respectively.
Results
Elbow flexion shows a significant difference (p < 0.0001) between I, R, R2. Abduction/adduction shows a significant difference between I-R (p < 0.0001) and I-R2 (p < 0.0001). Supination does not show a significant difference in mean maximum amplitude, but between 40 and 70%, there are significant differences. There is a significant mean decrease of lever arm in flexion (28%) and supination (50%) after superficial and deep part of the lacertus fibrosus release.
Conclusion
The results of this study show that the lacertus fibrosus increases the lever arm during flexion and supination. It limits the flexion and abduction of the elbow and supination of the forearm. Lacertus fibrosus maintains the rhythmicity between the elbow flexion and supination of the forearm.
Level of evidence
Basic science study, biomechanics
Details
; Coupier Jérôme 1 ; Beyer Benoît 1 ; Salvia, Patrick 1 ; Lefèvre, Philippe 1 ; Van Sint Jan Serge 1 ; Rooze Marcel 1 ; Feipel Véronique 1 1 Université Libre de Bruxelles ULB, Laboratory of Anatomy, Biomechanics and Organogenesis (LABO), Faculty of Medicine, Brussels, Belgium (GRID:grid.4989.c) (ISNI:0000 0001 2348 0746); Université Libre de Bruxelles ULB, Laboratory for Functional Anatomy, Faculty of Motor Sciences, Brussels, Belgium (GRID:grid.4989.c) (ISNI:0000 0001 2348 0746)