The medial palpebral ligament (medial canthal tendon) is a bilaminar fibrous band connecting the medial ends of the superior and inferior tarsal plates to the medial orbital wall. The anterior limb attaches to the anterior lacrimal crest of the maxilla, and the posterior limb attaches to the posterior lacrimal crest of the lacrimal bone, enclosing the lacrimal sac between them. The preseptal and pretarsal orbicularis oculi muscles arise from the two limbs.
Anchors the medial canthus to the orbital rim, maintains the medial canthal angle at approximately 30 degrees, supports the lacrimal pump mechanism by straddling the lacrimal sac, and provides the medial origin for the orbicularis oculi.
The medial palpebral ligament is the key structure in medial canthal reconstruction after trauma or tumour resection. Disruption produces telecanthus (widened intercanthal distance) and rounding of the medial canthal angle. Repair requires precise reattachment to the posterior lacrimal crest to restore the correct anatomical angle. The posterior limb attachment is most important for canthus position. Dacryocystorhinostomy for blocked nasolacrimal duct requires careful dissection around the medial canthal tendon to access the lacrimal sac.
Traumatic avulsion of the medial palpebral ligament in naso-orbito-ethmoid fractures produces telecanthus and epiphora from lacrimal pump failure, requiring transnasal wiring through the intact contralateral bone or plating to restore the intercanthal distance.
Chronic obstruction of the nasolacrimal duct between the lacrimal sac and inferior meatus, lying adjacent to the medial palpebral ligament, causes epiphora and dacryocystitis requiring dacryocystorhinostomy creating a new bypass through the lacrimal bone into the nasal cavity.
