Spreader Grafts vs. Autospreader Flaps: What Actually Holds the Middle Vault Open

When a surgeon removes a dorsal hump, something structurally important happens that most patients never hear explained. The upper lateral cartilages, which form the sidewalls of the middle third of the nose, are attached to the septum along the bridge. Taking down the hump detaches them from their anchor. Left unsupported, those sidewalls can drift inward over months to years, narrowing the internal nasal valve. The result is the classic post-rhinoplasty complaint: a nose that looks fine at rest but feels blocked, especially on inspiration, sometimes paired with a pinched or "inverted V" appearance across the middle of the bridge.

Two techniques exist to prevent this: the spreader graft and the autospreader flap (also called a spreader flap or turn-in flap). Both aim to hold the upper lateral cartilages away from the septum and keep the internal nasal valve angle above the roughly 10 to 15 degrees needed for comfortable airflow. They get there by different mechanical routes.

A spreader graft is a separate strip of cartilage, usually harvested from the patient's own septum, carved to roughly 1 to 3 millimeters thick and 15 to 25 millimeters long. The surgeon sutures one graft, or one on each side, between the dorsal edge of the septum and the upper lateral cartilage. Mechanically, it works like a shim: it physically occupies space, pushing the sidewall laterally and resisting the scar contracture that pulls tissues inward during healing. Because the graft is rigid and independent of the sidewall itself, it can also straighten a deviated dorsal septum when placed asymmetrically, which is why spreader grafts remain the standard tool in crooked nose correction and revision cases.

An autospreader flap takes a different approach. Instead of adding tissue, the surgeon preserves the excess upper lateral cartilage that would otherwise be trimmed during hump reduction, then folds it inward on itself and sutures the folded edge to the septum. The patient's own sidewall cartilage becomes the spacer. Mechanically this is elegant: no donor site, no separate graft to carve, and the fold adds a small amount of thickness that softens the dorsal aesthetic lines, which many surgeons consider an advantage in noses with thin skin where graft edges can become visible over time.

So which is better? The honest answer from the comparative literature is that for routine primary rhinoplasty with modest hump reduction, outcomes for breathing and appearance are broadly similar between the two. Studies measuring internal valve angles and patient-reported obstruction scores generally find both techniques effective at preventing midvault collapse when performed correctly.

The differences show up at the margins, and they follow directly from the mechanics. Autospreader flaps depend on there being enough redundant upper lateral cartilage to fold. Small humps under about 2 to 3 millimeters may not leave enough material, and very large reductions can leave cartilage that is too flimsy after trimming. Flaps also cannot straighten a crooked septum, because they have no independent rigidity: they follow whatever line the septum takes. Spreader grafts, being separate rigid struts, can push, brace, and camouflage asymmetry, which is why they dominate in revision surgery, trauma cases, and significant deviation.

Spreader grafts carry their own costs. Harvesting septal cartilage requires a septoplasty-style dissection even if the septum did not otherwise need work, and it consumes graft material that might be wanted later if a revision ever becomes necessary. In thin-skinned patients, a graft placed slightly too high can create visible or palpable edges along the bridge. And any free graft depends on suture fixation holding through the healing period, whereas a flap remains attached to its native blood supply and position.

Many surgeons now use hybrid logic rather than loyalty to one technique. A common pattern: autospreader flaps for straightforward primary hump reductions where the septum is midline, spreader grafts when deviation or valve collapse is already present, and occasionally both together, with a flap on one side and a graft on the other to correct asymmetry.

What should a patient actually take from this? Three practical points. First, if your surgical plan includes hump reduction, it is reasonable to ask how the midvault will be reconstructed, because skipping this step is a known driver of late breathing problems and revision surgery. Second, neither technique is universally superior; the right choice depends on hump size, septal position, skin thickness, and whether this is a first or repeat operation. Third, midvault work is largely invisible in early photos. Its value shows up years later, in a bridge that has not narrowed and an airway that still works. That is the quiet job both techniques were designed to do.

Related reading: Spreader Grafts Explained: Structural Support in Rhinoplasty.