Three-dimensional Analysis of the Attachment and Path of the Transverse Carpal Ligament

The purpose of this study was to describe and evaluate the detailed anatomic locations and areas of ligamentous attachments and paths of the transverse carpal ligament (TCL) on a three-dimensional (3-D) surface model.

Ten fresh-frozen cadaver wrists were used to dissect and identify the TCL. Their ligament attachments and whole bone surfaces were digitized three-dimensionally and their areas evaluated. The attachments of each ligament were represented in a model combining CT surfaces overlaid by a digitized 3-D surface, and were also visually depicted with a different color for each on 3-D images of the bones.

The TCL was found to be composed of two or three discrete ligaments. Both the trapezium-hook of hamate ligament and the trapezium-pisiform ligament were identified in all ten specimens. The scaphoid-pisiform ligament was found in only two of the ten specimens. The average areas of the attachments of the TCL were 42.7 mm(2) on the trapezium, 30.0 mm(2) on the hook of hamate, 21.6 mm(2) on the pisiform, and 12.7 mm(2) on the scaphoid.

The anatomic 3-D attachment sites of the TCL were visually shown qualitatively, and their areas quantified. This 3-D information offers further knowledge and understanding of the anatomy and biomechanics of the TCL. It could also help in the accurate assessment of radiographic images and treatment of various wrist injuries and diseases when performing such procedures as carpal tunnel release, Guyon's canal release, trapeziectomy, hook of hamate excision, or arthroscopy.