Anatomical study of the latissimus dorsi muscle flap / Estudio anatómico del colgajo del músculo latísimo del dorso

SUMMARY: The latissimus dorsi is a broad muscle that originates from the inferior thoracic spinous processes, thoracolumbar fascia, iliac crest, and inferior ribs. It inserts on the inferior aspect of the intertubercular groove of the humerus through a thin tendon. The study was conducted on 10 cadavers (7 male and 3 female). These specimens were dissected and examined to study the gross anatomical characteristics of the latissimus dorsi muscle. The dimensions of the latissimus dorsi muscle and its surface area were measured in all the cadavers. The branching pattern of the thoracodorsal vessels was recorded. The pedicle length and caliper were measured using Vernier calipers. On the 20 dissected sides, the thoracodorsal artery was found to be one of the terminal branches of the subscapular artery that originates in the axillary region. In 19 (95 %) cases, the thoracodorsal artery terminated in a bifurcation, giving off a medial and a lateral branch. The average size of the elevated flap of the latissimus dorsi muscle was 18 cm x 36 cm. The average pedicle length was 9.5 cm (range: 5 cm-14 cm), and the average diameter at its origin was 2.5 mm (range: 1.5 mm-3.5 mm). The average diameter of the vena comitans was 3.3 mm. The current study focuses on the anatomical features of the latissimus dorsi muscle and its blood supply to increase the success rate of operations in clinical practice.

RESUMEN: El músculo latísimo del dorso se origina en los procesos espinosos de las vértebras torácicas inferiores, la fascia toracolumbar, la cresta ilíaca y las costillas inferiores y se inserta en el surco intertubercular del húmero a través de un delgado tendón. El estudio se realizó en 10 cadáveres (7 mujeres y 3 hombres). Estos especímenes fueron disecados y examinados para estudiar las características anatómicas macroscópicas del músculo latísimo del dorso. En todos los cadáveres se midieron las dimensiones del músculo y su superficie. Se registró el patrón de ramificación de los vasos toracodorsales. La longitud del pedículo y el calibre se midieron con paquímetro Vernier. En los veinte lados disecados, se encontró que la arteria toracodorsal era una de las ramas terminales de la arteria subescapular que se originaba en la región axilar. En 19 (95 %) casos, la arteria toracodorsal terminaba bifurcándose en dos ramas, una rama medial y otra lateral. El tamaño promedio del colgajo elevado del músculo latísimo del dorso era de 18 cm x 36 cm. La longitud promedio del pedículo era de 9,5 cm (rango: 5 cm-14 cm), y el diámetro promedio en su origen era de 2,5 mm (rango: 1,5 mm-3,5 mm). El diámetro medio de la vena comitans era de 3,3 mm. El estudio actual se centra en las características anatómicas del músculo latísimo del dorso y su irrigación para aumentar la tasa de éxito de las operaciones en la práctica clínica.

Intra and postoperative evaluations of microcirculation and micro-rheological parameters in a rat model of musculocutaneous flap ischemia-reperfusion

PURPOSE:To examine how the ischemia-reperfusion injury of latissimus dorsi-cutaneous maximus (LDCM) musculocutaneous flap affects the microcirculatory (flap's skin surface) and hemorheological parameters, and whether an intraoperative deterioration would predictively suggest flap failure in the postoperative period.METHODS: Ten healthy male rats were subjected to the study. In Group I the left flap was sutured back after 2-hour, while the contralateral side was right after its elevation. In Group II the same technique was applied, but the pedicle of the left flap was atraumatically clamped for 2-hour. The contralateral side was left intact. On the flap skin surface laser Doppler tissue flowmetry measurements were done before and after and during the protocols applied in the groups. Microcirculatory and hemorheological examinations were done postoperatively.RESULTS: The microcirculatory parameters significantly decreased during immobilization and ischemia. Afterwards, all the regions showed normalization. In the retrospective analysis there was a prominent difference between the microcirculatory parameters of necrotic and survived flap during the early postoperative days (1-3) in Group II. Erythrocyte aggregation and deformability showed only slight differences.CONCLUSIONS: Two-hour ischemia and reperfusion caused deterioration in latissimus dorsi-cutaneous maximus flap microcirculation. Predicting the possible postoperative complication, the intraoperative laser Doppler measurement can be informative.