Neurovascular structures of the ligament of the head of femur

Abstract

The ligament of the head of femur (LHF), or ligamentum teres, is believed to provide blood supply to the head of femur and mechanical stability to the hip joint. But these functions in the adult are often debated. The existence and distribution of neurovascular structures within the ligament are not widely documented. This study examined the blood vessels and nervous tissue within the LHF to determine whether the ligament may have a vascular and proprioceptive function at the hip joint. Histological sections from the LHF from 10 embalmed hips (six female, four male; mean age 80.4 ± 8.7 years) were cut at three levels: the foveal attachment, mid‐length and its base where it attaches to the transverse acetabular ligament. Sections were stained with haematoxylin and eosin to study general tissue architecture or with von Willebrand factor and neurofilament to identify blood vessels and nervous tissue, respectively. The proportion of the ligament's cross‐sectional area occupied by blood vessels was expressed as a vascularity index (VI). Nerve endings within the ligament were identified and morphologically classified. Comparisons between the VI at the three levels, or between the tissue layers of the ligament, were made using 95% confidence intervals; statistical significance was set P < 0.05. The ligament tissue comprised three distinct layers: a synovial lining with cuboidal cells, a sub‐synovial zone formed of loose connective tissue and the ligament proper composed of dense collagen bundles. Patent blood vessels and nerve fibres were present both in the sub‐synovial zone and the ligament proper; Pacinian corpuscles and free nerve endings were found scattered only in the sub‐synovial zone. The VI of the ligament proper at the fovea was significantly higher than its middle (P = 0.01) and basal levels (P = 0.04); it was also higher than that of the sub‐synovial layer (P = 0.04). The LHF has three histologically distinct zones, and blood vessels and nerves are distributed both in the sub‐synovial layer and ligament proper. Higher vascularity within the ligament proper at its foveal insertion suggests a possible nutritive role of the LHF to the adult head of femur. The presence of nerves and nerve receptors indicates the ligament is involved in the perception of pain and proprioception, thereby contributing to mechanical stability of the joint.

The morphology of the subacromial and related shoulder bursae. An anatomical and histological study

“…Blood vessel density was calculated as a percentage of the area of the ROI that was occupied by blood vessels for each section (Perumal et al, 2019). The median and interquartile range (IQR) of blood vessel density were calculated for all samples combined, and for specific areas of each bursa.…”

Early efficacy of rotational osteotomy of the femoral neck with preservation of the round ligament in the treatment of osteonecrosis of the femoral head

“…The presence and integrity of central concave vessels in the round ligament of the femoral head were observed in 61% of the 266 patients in the Barrington et al [30] study. Perumal et al [31] also found a high distribution of vessels in the central concave round ligament of the femoral head as well as the presence of nerves and neuroreceptors, which suggests that the round ligament is involved in the perception of pain and proprioception. Therefore, our team believes that the destruction of the round ligament during rotational osteotomy of the femoral neck using surgical dislocation techniques may cause the following three problems: 1. loss of hip stability, leading to secondary femoral head collapse or even osteoarthritis; 2. destruction of hip proprioception; and 3. destruction of the blood supply to the femoral head concavity.…”

Comparative histomorphological analysis of elbow ligaments and capsule

“…Stained slices were analyzed in transmission and polarization mode, using 20×, 40×, 200×, and 400× magnification. HE staining was used for the qualitative determination of the structure and composition of collagen (Costa et al, 2018; Perumal et al, 2019; Zhang et al, 2018), EvG staining for the occurrence and semiquantitative distribution of elastic fibers (Chan et al, 2007; Sawatsubashi et al, 2010; Sencimen et al, 2009). The anisotropic arrangement of collagen fibers was classified into four types by using polarization microscopy: densely packed parallel, mixed tight and loose parallel, densely interlaced, and mixed tight and loose interlaced (Rein et al, 2015; Rein et al, 2020; Semisch et al, 2016).…”