Paul Jules Tillaux was a French surgeon that is the namesake of the spiral of Tillaux, an imaginary curve through the insertions of the eye’s rectus muscles.
There are six extraocular muscles that control the movement of the eye (the legendary 7th extraocular muscle, the levator palpebrae, controls eyelid elevation). These are:
- Medial rectus
- Lateral rectus
- Superior rectus
- Inferior rectus
- Superior oblique
- Inferior oblique
The 4 rectus muscles originate in the back of orbit at the annulus of Zinn and insert anteriorly on the globe near the limbus. Starting from the superior rectus and going to the lateral rectus, inferior rectus, and medial rectus, the muscle insertions lie progressively closer to the limbus (border between the cornea and sclera). This forms the aforementioned spiral of Tillaux.
As seen in the image above, for the average adult, the medial rectus inserts 5.5mm from the limbus, the inferior rectus 6.5mm, the lateral rectus 6.9mm, and the superior rectus 7.7mm. For the time-crunched resident reviewing for OKAPs, Dr. Pouw and Dr. Young on Eyes for Ears remind us that these values may be more easily remembered as 5.5, 6.6, 7.7, and 7.0.
The spiral of Tillaux has some importance when performing ophthalmic surgery. As the superior rectus insertion is quite posterior, a scleral pass that is too deep may perforate the retina (it doesn’t help that the sclera is the thinnest [a mere 0.3mm] directly posterior to the rectus muscle insertions). In cases when there is a remote history of strabismus surgery but the amount of advancement or recession is unknown, measurements of muscle insertions from the limbus may allow the surgeon to estimate the extent of previous surgeries.
Other Eponyms
Like many other surgeons of yesteryear, Dr. Tillaux is honored with eponyms across a variety of fields. He is best known to orthopedic surgeons for the Tillaux-Chaput fracture, an unusual fracture of the anterolateral tibial epiphysis. This Salter-Harris III fracture is most commonly seen in adolescents after forced lateral rotation of the foot.
The Tillaux maneuver is a physical exam technique to demonstrate adherence of a breast tumor to the pectoralis major.
There is also a Tillaux apparatus that maintains femoral diaphysis fractures in constant, steady adduction; Tillaux’s sign, an indication of a mesenteric tumor; and a Tillaux painful crepitus sign tenosynovitis of the adductor and short extensor of the thumb.
References
- https://eyesforears.net/episodes/2019/12/26/episode-34-strabismus-fundamentals-part-i
- American Academy of Ophthalmology,. (2021). 2021-2022 Basic and Clinical Science Course, Section 02: Fundamentals and Principles of Ophthalmology. Page 18-20.
- https://www.orthobullets.com/pediatrics/4028/tillaux-fractures
- https://litfl.com/paul-jules-tillaux-eponym/
Tillaux's Thoughts 