Tensile properties of the transverse carpal ligament and carpal tunnel complex

• A novel method and unique testing procedure has been developed.
• The procedure is uncomplicated and designed to determine the tensile properties of the transverse carpal ligament.
• Clinical and biomedical engineering researchers will benefit from this procedure.

BackgroundA new sophisticated method that uses video analysis techniques together with a Maillon Rapide Delta to determine the tensile properties of the transverse carpal ligament–carpal tunnel complex has been developed.MethodsSix embalmed cadaveric specimens amputated at the mid-forearm and aged (mean (SD)): 82 (6.29) years were tested. The six hands were from three males (four hands) and one female (two hands). Using trigonometry and geometry the elongation and strain of the transverse carpal ligament and carpal arch were calculated. The cross-sectional area of the transverse carpal ligament was determined. Tensile properties of the transverse carpal ligament–carpal tunnel complex and Load–Displacement data were also obtained. Descriptive statistics, one-way ANOVA together with a post-hoc analysis (Tukey) and t-tests were incorporated.FindingsA transverse carpal ligament–carpal tunnel complex novel testing method has been developed. The results suggest that there were no significant differences between the original transverse carpal ligament width and transverse carpal ligament at peak elongation (P = 0.108). There were significant differences between the original carpal arch width and carpal arch width at peak elongation (P = 0.002). The transverse carpal ligament failed either at the mid-substance or at their bony attachments. At maximum deformation the peak load and maximum transverse carpal ligament displacements ranged from 285.74 N to 1369.66 N and 7.09 mm to 18.55 mm respectively. The transverse carpal ligament cross-sectional area mean (SD) was 27.21 (3.41)mm2.InterpretationUsing this method the results provide useful biomechanical information and data about the tensile properties of the transverse carpal ligament–carpal tunnel complex.