Roll cartilage

Drawing of the left eyeball and the external eye muscles; the trochlea can be seen in the upper left

The roll cartilage or the trochlea musculi obliqui superioris ( trochlea , Latin: "wind", "pulley") is an approximately 3 mm thick ring of cartilage on the anterior, inner (medial) upper edge of the eye socket ( orbit ), which is connected to the frontal bone anchored. It has the function of deflecting the course of the upper oblique eye muscle ( Musculus obliquus superior ) outwards (laterally) behind and thus giving it a different direction of pull. So that the tendon of the muscle can run smoothly through the cartilage ring, it is lined with a smooth synovial membrane . From the outer edge of the trochlea, a tight connective tissue pulls laterally as a tendon sheath and connects to the upper tether and the ring ligament .

Malfunctions

Two main trochlea disorders are known that affect the ability of the muscle tendon to move through the ring of cartilage: superior oblique click syndrome and superior oblique tendon sheath syndrome ( Brown syndrome ). In both clinical pictures there is a spindle-shaped thickening of the tendon, which means that it can only be pulled through the trochlea with very great force and results in passive movement restriction of the eye. In the first case, the resulting disabilities are intermittent, whereas in Brown's syndrome they are permanent.

See also

• Periorbita

literature

• Herbert Kaufmann (Ed.): Strabismus. Enke, Stuttgart 1986, ISBN 3-432-95391-7 .

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !