Research Article

Comparative Analysis of Vascular Density in the Femoral Head Ligament of the Dog, Sheep, and Goat

Imani Stanard, Hazem Almhanna, Aqeel Mohsin Mahdi Al-Mahmodi, David Kilroy­ㅤ, Arun HS Kumar

Abstract

Background: The ligament of the head of the femur (ligamentum teres) is an intra-articular structure that contributes to hip joint stability and serves as a potential conduit for vascular supply to the femoral head. Despite its recognised anatomical presence across mammalian species, its vascular capacity and functional significance remain incompletely understood. This study aimed to comparatively evaluate vascular density within the ligament of the femoral head in adult dog, sheep, and goat, and to determine whether a relationship exists between ligament length and vascular characteristics. Materials and Methods: Nine cadavers (three specimens each of adult dog, sheep, and goat) were examined. Ligament length was measured macroscopically, and selected samples were processed for histological analysis using haematoxylin and eosin staining. High-resolution images were analysed using ImageJ software to quantify blood vessel area and vascular density. Statistical analysis was performed using one-way ANOVA followed by Bonferroni post hoc testing, with significance set at p<0.05. Results: Ligament length ranged from 13-22 mm in dogs and 20-22 mm in both sheep and goats. No correlation was identified between ligament length and blood vessel area. However, significant interspecies differences in vascularity were observed. Goats exhibited a significantly greater mean blood vessel area (47,025.58 μm²) and higher vascular density compared to both dogs (10,289.43 μm²) and sheep (5,806.94