Why does a lateral tarsal strip re-anchor to this tubercle rather than to the rim surface?

The lateral canthal tendon inserts on the Whitnall (lateral orbital) tubercle just inside the rim, holding the lid margin back against the globe. Re-anchoring a tarsal strip to the tubercle — not to the anterior rim — reproduces this posterior vector, so the tightened lid hugs the eye instead of standing away from it. The lateral (Whitnall) orbital tubercle is the common insertion for four structures: the lateral rectus check ligament, the lateral horn of the levator aponeurosis, the lateral canthal tendon, and Lockwood's suspensory ligament. The superior transverse (Whitnall) *ligament* is a separate structure that attaches to the orbital wall roughly 10 mm above the tubercle via the fascia of the lacrimal gland — it does not insert on the tubercle itself.