Anatomy of the lateral canthal tendon

The purpose of this study was to clarify and describe the anatomy of the lateral canthal tendon. Knowledge of this anatomy is essential in selection of appropriate surgical procedures to restore orbital anatomy.

Gross dissections were performed of the lateral orbital soft tissues from 21 preserved Caucasian cadaveric orbits. A block of the bony attachment of each lateral canthus was taken for histologic examination. After anatomical exposure, the following measurements of the lateral canthus were made: (1) the distance from the midpoint of insertion of the lateral canthus at the lateral orbit to the zygomaticofrontal suture; (2) the horizontal width of the lateral canthus, as measured from the lateral commissure to the lateral orbit; (3) the vertical difference in height between the medial canthal and lateral canthal insertions.

The mean midpoint of the lateral canthus insertion was 10. 24 mm inferior to the zygomaticofrontal suture (range, 5-15 mm). The mean horizontal length of the lateral canthus from the lateral commissure to the lateral orbit was 7.52 mm (range, 2-12 mm). The mean vertical difference in height between the insertions of the medial canthus and the lateral canthus was 1.35 mm (range, -2-4 mm), the lateral canthus being at a more superior point. Histologic examination of hematoxylin-eosin-stained slides showed that the fibers of the lateral canthus inserted into the periosteum but not beyond it.

The lateral canthal tendon attaches the upper and lower tarsal plates to Whitnall's tubercle inside the orbital rim deep to the septum. A precise knowledge of the periorbital anatomy will assist the surgeon in the selection of appropriate surgical techniques that will provide for restoration of this delicate anatomical configuration.