Biomechanics of the helical rim advancement flap.

Abstract

To determine how helical rim closure with advancement flaps affects ear length and cupping, to compare the tension of closure with wedge excision and helical rim advancement and the effects of 3 tension-decreasing surgical techniques, and to review clinical experience with this flap. The laboratory study was performed on 6 fresh cadaver ears, by means of sequential excision of tissue, and closure tension was measured with a strain gauge. Results obtained in 10 patients were reviewed. University referral hospital. Ten patients with helical rim defects treated with helical rim advancement flaps. In cadaver ears, a helical rim defect of 5 mm was enlarged sequentially to 10 mm, 15 mm, and finally 20 mm. In the patients, defects of the helical rim caused by trauma or tumor were closed by this helical rim advancement flap method. For the laboratory study, the outcome measures were tension of closure of the defect, ear length, and ear cupping. For the review of cases, outcome was determination of perioperative complications and the patient's and surgeon's judgment of cosmetic appearance. Closure of a helical rim defect with advancement flaps caused minor shortening and moderate cupping of the ear. The tension of closure was decreased by extending the inferior incision into the earlobe, creating a Burow triangle, and shaving cartilage from the scapha. Both the Burow triangle and the scaphal shave caused mild increases in ear cupping. Helical rim advancement flaps provide satisfactory closure of helical rim defects up to at least 20 mm (longer in some ears) with excellent preservation of normal anatomic landmarks and a near-normal appearance of the reconstructed ear.