Ear Reconstruction

The external ear (auricle) is a complex three-dimensional structure composed of elastic cartilage covered by thin skin with minimal subcutaneous tissue. The anterior surface skin is tightly adherent to the underlying perichondrium, while the posterior surface has slightly more subcutaneous tissue and mobility. The auricular framework consists of a single sheet of elastic cartilage that forms the helix, antihelix (with its superior and inferior crura), tragus, antitragus, and the conchal bowl. The lobule is the only part of the auricle lacking cartilage. It consists solely of fibroadipose tissue covered by skin. Vascular supply is provided by the superficial temporal artery (anteriorly) and posterior auricular artery (posteriorly), with a rich subdermal plexus that allows reliable flap perfusion even with narrow pedicles. The sensory innervation is complex, involving the great auricular nerve (C2-C3), auriculotemporal nerve (V3), and Arnold nerve (vagus). The key functional anatomy is the external auditory canal, which must not be narrowed or stenosed during reconstruction. The pre- and postauricular skin provides excellent donor tissue for full-thickness skin grafts due to its color and texture match to facial skin.

Ear reconstruction follows a stepwise approach from simple to complex, guided by defect size, location, depth, and involvement of the helical rim. The reconstructive ladder begins with secondary intention healing for concave surfaces (conchal bowl, antihelix, triangular fossa), progresses through wedge excision for small helical rim defects, Antia-Buch helical advancement for moderate rim defects, and extends to retroauricular interpolation flaps, revolving door flaps, composite grafts, and skin grafts for larger or more complex defects. The choice of technique is driven by the primary reconstructive goals: maintenance of auricular contour (particularly the helical rim), preservation of ear canal patency, avoidance of excessive ear size reduction, and skin coverage of exposed cartilage.

Secondary intention healing is often the optimal choice for defects on concave auricular surfaces. The conchal bowl, antihelix, triangular fossa, and scapha. These concave surfaces heal by contraction and re-epithelialization with minimal distortion, often producing cosmetic results superior to those achievable with skin grafts or flaps. The wound contracts toward the center of the concavity, and the resulting scar typically blends well with the surrounding contour. The critical requirement for successful secondary intention healing on the ear is that the perichondrium must be intact. When cartilage is exposed without its perichondrial covering, secondary intention is contraindicated because exposed cartilage will not granulate, is prone to desiccation and chondritis, and will result in a poor cosmetic outcome with cartilage necrosis. For defects with exposed cartilage, the cartilage should be trimmed back to where perichondrium is present, or a skin graft or flap should be used instead. Postoperative care involves keeping the wound moist with petrolatum-based ointment and non-adherent dressings, typically for 4 to 8 weeks depending on defect size.

Wedge excision is the simplest method for reconstructing helical rim defects involving up to approximately 25% of the total helical circumference. A full-thickness wedge (including skin, cartilage, and posterior skin) is excised, and the wound edges are reapproximated in layers: cartilage with absorbable suture (5-0 PDS or Vicryl), anterior and posterior skin with nonabsorbable or fast-absorbing suture. The pentagonal modification (sometimes called the star or bursting-star excision) converts the simple wedge into a pentagon by adding small triangular extensions at the base of the wedge along the helical rim. This modification distributes tension more broadly, reduces the risk of notching at the apex, and allows closure of slightly larger defects without excessive tension. When performing any wedge excision, the cartilage should be trimmed slightly shorter than the overlying skin edges (by 1-2 mm) to allow skin eversion and prevent a palpable cartilaginous step-off at the closure site. The major limitation of wedge excision is that it reduces the overall ear size, and serial wedge excisions may produce a noticeably smaller ear.

The Antia-Buch chondrocutaneous advancement flap is the technique of choice for moderate helical rim defects ranging from approximately 1.5 to 2.5 cm, which are too large for primary wedge closure but do not require the complexity of a two-stage interpolation flap. The technique involves mobilizing the remaining helical rim above and below the defect as chondrocutaneous advancement flaps. Composite units of skin and cartilage that slide along the helical rim to close the gap. For the superior component, a full-thickness incision is made along the helical rim extending superiorly from the defect, and the helical-scaphal composite is advanced inferiorly. A V-Y advancement or Burow triangle at the helical root provides the tissue release. For the inferior component, the helical-lobular composite is advanced superiorly, with a V-Y release at the lobule. The two advancing segments meet at the defect site and are sutured together. The key advantage of the Antia-Buch flap is that it maintains the natural curvature of the helical rim using the patient's own rim tissue, producing a smooth, continuous contour. The ear is slightly reduced in size (typically by the width of the defect), but the overall shape is preserved.

The retroauricular interpolation flap is a two-stage procedure indicated for large helical, antihelical, and conchal defects that exceed the reach of local advancement techniques. The flap is designed on the postauricular surface (mastoid skin), based superiorly or inferiorly on the posterior auricular artery branches. At the first stage, the flap is elevated and transposed through or around the auricular margin to cover the anterior defect. The pedicle bridges the auricular rim and is divided at 3 weeks, at which time the remaining pedicle is inset and the donor site is either closed primarily or skin-grafted. This flap provides excellent tissue bulk and vascularity but requires two procedures and produces a posterior scar. The revolving door (trapdoor) flap is a single-stage island flap used primarily for conchal bowl defects that extend to the antihelix. A full-thickness island of conchal bowl tissue (skin, cartilage, perichondrium, and posterior skin) is elevated on its posterior vascular pedicle, rotated 180 degrees through the cartilage defect, and inset into the antihelical or helical defect. The posterior conchal donor site is then skin-grafted or closed primarily. This flap is particularly useful because it brings cartilage-bearing tissue to reconstruct defects requiring structural support.

Composite grafts from the contralateral ear are used for small full-thickness helical rim defects under 1.5 cm. The graft is harvested from the corresponding location on the opposite ear (helical root, crus of helix, or conchal cartilage with overlying skin) and transferred as a composite unit containing skin, cartilage, and sometimes perichondrium. Graft survival depends entirely on diffusion and inosculation from the recipient wound bed, limiting the maximum graft dimension to approximately 1.5 cm (no point on the graft should be more than 5-7 mm from a vascularized wound edge). The graft must be secured with precise suturing and a firm bolster dressing to prevent shearing. Partial graft necrosis (particularly of the distal tip) is not uncommon but often heals with acceptable cosmesis. Full-thickness skin grafts (FTSG) are used for cartilage-deep defects when perichondrium is intact but local flap options are limited. The pre- and postauricular skin provides an ideal FTSG donor for auricular reconstruction due to its thin profile and excellent color match. The graft is secured with a bolster dressing for 5 to 7 days. Split-thickness skin grafts (STSG) are rarely used on the ear because they contract excessively and produce poor color and texture match.

The most significant complication of ear reconstruction is chondritis, an infection of the auricular cartilage most commonly caused by Pseudomonas aeruginosa. Chondritis presents with severe pain, erythema, and swelling of the ear, progressing to cartilage necrosis and permanent deformity if untreated. Prevention includes meticulous hemostasis, avoidance of tight dressings that compress the auricular vasculature, topical fluoroquinolone prophylaxis for wounds with cartilage exposure, and instruction to patients to avoid sleeping on the operative ear. Treatment requires systemic antipseudomonal antibiotics (fluoroquinolone) and often surgical debridement of necrotic cartilage. Ear canal stenosis is a risk when defects involve the conchal bowl near the external auditory meatus. Always maintain a minimum cartilage rim around the canal aperture and consider stenting during the healing period. Hematoma formation between skin and cartilage can cause pressure necrosis of the overlying skin and a cauliflower ear deformity; bolster dressings with through-and-through sutures prevent hematoma accumulation. Hypertrophic scarring is more common on the posterior auricular surface than the anterior. Finally, auricular prosthetics should be discussed as an alternative for patients with very large or total auricular defects, advanced age, or significant comorbidities that preclude multistage reconstruction.