The “Jigsaw Puzzle” Advancement Flap for Reconstruction of a Retroauricular Surgical Defect

An 89-year-old man presented with a large basal cell carcinoma tumor on his right retroauricular area adjacent to the mastoid–auricle border (Figure 1). The clinical tumor size was 17 × 17 mm. The tumor was excised in one stage, using the Mohs micrographic surgery technique. The final defect size was 20 × 20 mm (Figure 2). How would you reconstruct this defect?

Repairing retroauricular defects is quite challenging. Although direct observation of the repaired defect is not possible, choosing the wrong reconstruction might result in serious deformity of the auricle that will be easily noticed. Depending on the auricle size and skin mobility, several options are possible. In older individuals with large auricles where there is excess of skin, primary closure might be possible in small defects, but in larger defects, closure will be dealt with by simple transposition, rotation, or even a bilobed flap.¹ If feasible, attempts at undermining and direct closure will obliterate the retroauricular sulcus and flatten the auriculocephalic angle, making it hard for the patient to wear spectacles and causing asymmetry with the contralateral ear. In younger individuals or small auricles with tight skin or very large defects, recruitment of the laxity of the skin over the mastoid area should be used.

We describe a technique that was described by Goldberg et al for repairing lateral nasal ala defects.² Using a template of the defect, we draw an advancement flap on the adjacent mastoid skin with dog-ears lateral to the defect template along the retroauricular fold. We excised the dog-ears and incised the flap (Figures 1 and 2). Excess fat should be trimmed. Then we raised the flap and anchored it to the defect (Figure 3) using 4-0 subcutaneous absorbable sutures. The final cutaneous closure was done with running 6-0 nylon sutures.

We used the excess skin of the adjacent mastoid area as a flap because of the similarity in the thickness and texture. The retroauricular fold was used to hide the surgical scars.

This flap allows us to use the mastoid skin to cover the defect without disfiguring the auricle and without risking the graft with necrosis, as the width and vascularity of the flap are sufficient. Special care must be emphasized on the width of the base of the flap, as too narrow a neck will result in flap necrosis.

• This is an advancement flap whose dog-ears are hidden in a major skin fold.
• Skin texture and thickness are identical.
• Excess fat should be trimmed.
• Special care should be placed on the pedicle width.