The variable almost nobody researches
Patients preparing for under-eye fat repositioning research the approach — conjunctival or incisional — and they research side effects. Almost nobody asks how the repositioned fat will be held in place. Yet for a natural contour that lasts, the fixation method is one of the most consequential choices in the entire operation: it decides whether the fat stays where the surgeon placed it after the sutures come out, the swelling settles, and the face returns to daily movement. If you take one question into your consultation from this article, make it this one.
Thirty seconds of anatomy
A brief recap so the comparison makes sense. The bulge is orbital fat wrapped in its membrane, pushing outward above the tear trough; the trough itself is pinned down by a band, which is why the under-eye reads as a ridge above a valley, with shadow and often darkness in between. Repositioning releases the band, brings the bulging fat down over the rim, spreads it across the trough, and fixes it there. Everything up to the last step can be done identically — the two fixation philosophies part ways at how that final anchoring happens.
External fixation: threads that come out through the skin
In external fixation, the sutures holding the repositioned fat are passed outward through the cheek skin and tied on the outside. Two consequences follow. First, the fat is suspended against the underside of the muscle and skin — it is not anchored to the bone membrane. Second, threads tied on the face cannot stay there: left too long they mark the skin, so they are removed within about a week. That week is also cosmetically awkward — visible threads on the mid-face — but the structural point is what happens at removal. Once the external knots are released, nothing rigid holds the fat at its new position, and it can ride back upward with the very tissues it was tied to. The hold was real, but temporary by design.
Internal fixation: sewn to the bone membrane from inside
Internal fixation anchors the fat from within: the periosteum — the membrane on the bone of the front cheek — is exposed, and the fat is sutured directly onto it at five points, with nothing passing out through the skin. There are no threads to see and no removal appointment on which the result depends. When non-dissolvable sutures are used, the anchoring is not waiting out a clock — the fixation persists, which is exactly what a structure under constant motion from blinking and expression requires. The trade is surgical: everything happens in a small internal space, and the periosteal knots must be tied precisely where they cannot simply be reached from outside.
Three axes: appearance, holding power, difficulty
Compared honestly along three axes: On appearance, external fixation shows threads on the face for about a week; internal fixation shows nothing. On holding power, external fixation suspends fat from soft tissue and must be undone within days, after which the position depends on early adhesion alone; internal fixation ties the fat to bone membrane with sutures that stay. On difficulty, external fixation wins — it needs less dissection, a shorter operation, and less swelling, which is precisely why it is widely used and why patients experience it as the easier surgery. Internal fixation demands working depth, periosteal exposure, and secure knots in a roughly two-centimeter conjunctival window — technique that takes sustained training and case volume to perform reliably. Neither list is hidden; they are two coherent philosophies with different priorities.
Why ST fixes internally
ST's position, stated as the surgeon's professional judgment rather than a universal verdict: a knot that must be untied in a week cannot be the long-term anchor of a structure you want to stay put for years. External fixation is chosen for good reasons — simplicity, speed, lighter recovery — but the durability of the hold is structurally weaker, because it was never attached to bone and never meant to remain. ST therefore performs internal fixation: five points, on the periosteum, with non-dissolvable sutures, accepting the harder operation in exchange for an anchoring that does not expire. Whichever clinic you consult, ask the question this article began with — how will my fat be held in place? — and listen for a specific answer.