Lateral crura-alar ring
Reviewed by Felipe Culaciati

Lateral crura incision or excision are common procedures for most rhinoplasty surgeons despite the fact that they have potential complications such as nostril rim retraction, bossa tip formation and alar wall collapse during breathing. Fortunately, nowadays there is a trend to preserve the lateral crura more. This article reviews the anatomy of the lateral crura in a two-part investigation consisting of a clinical measurement study of 40 consecutive rhinoplasty patients and 20 fresh cadaver dissections. Photography of patients preoperatively and intraoperatively of  lateral crura shape were taken, as well as measurements of alar orientation, alar cartilage axis and width. The purpose of the cadeveric study was to study the part of alar cartilages and alar rim that it was not possible to evaluate during clinical examination. The authors found that the avarage axis orientation of the lateral crura was 43.6º separated from the mid-nostril point in 5.9mm. The most common shape was smooth and straight in its horizontal axis with the cephalic border higher than the caudal one, measuring in avarage 10.1mm width in the vertical axis. Average lateral crural dimensions were 23.4mm long, 6.4mm wide at the domal notch, 11.1mm wide at the so-designated turning point (TP), and 0.5mm thickness. The accessory cartilage chain was present in all dissections. The lateral crura–alar ring was present in all dissections as a circular ring continuing around toward the anterior nasal spine but not abutting the pyriform. The lateral crura begins at the domal notch and ends at the accessory cartilages, it exhibits a distinct TP from the caudal border, has distinct horizontal and vertical vectors, and should have a caudal border higher than the cephalic border. The importance of this study resides in describing the anatomy of the lateral crura-alar rim complex. To achieve an ideal tip shape, rhinoplasty surgeons must clearly understand the anatomy, position, configuration and eventual lateral crura malposition in order to use the proper surgical techniques.

Rhinoplasty: the lateral crura-alar ring.
Daniel RK, Palhazi P, Gerbault O, Kosins AM.
AESTHETIC SURGERY JOURNAL
2014;34:526.