Anatomical measurements for degree orientation and muscle insertions for rectus muscles
Reviewed by Fiona Rowe

This study reports the relative degree orientation of the superior, lateral and inferior rectus muscles with respect to the medial rectus, and the distances between the rectus muscle insertions. The study involved 30 cadavers (60 eyes), all White, 50% female and mean age of 81.86 years, SD 12.16. With respect to the medial rectus, degree orientations were: superior rectus – mean 93.14, SD 3.04, minimum 82.3, maximum 100.3; lateral rectus – mean 180.21, SD 5.65, minimum 170.5, maximum 190.6; inferior rectus – mean 90.57, SD 4.47, minimum 84.0, maximum 98.9 degrees. Insertion distances were: medial to inferior rectus – mean 13.64, SD 0.54; inferior to lateral rectus – mean 13.79, SD 0.75; lateral to superior rectus – mean 13.54, SD 0.63; superior to medial rectus – mean 13.83, SD 0.75mm. Relative distances between midpoints of extraocular muscles were larger for males than females. There were no other significant differences for right or left eyes, or gender. This study provides useful information for planning ocular surgery.

A study of the relative orientation of the extraocular rectus muscles: an advanced cadaveric approach.
Barton AT, Rana VK, Kim EJ, et al.
STRABISMUS
2025;33(1):54–7.