MR imaging-anatomical-histological evaluation of the abdominal muscles, aponeurosis, and adductor tendon insertions on the pubic symphysis

PURPOSE: To perform an MR(magnetic resonance) imaging, anatomical, and histological evaluation of the abdominal muscles and adductor tendon insertions.

METHOD: Four fresh cadaveric pelvis specimens were imaged at 3 T with the following imaging parameters: TE (echo time)/TR (repetition time): 20, 4090, slice thickness: 2 mm, FOV: 270 × 90, matrix size: 512. Anatomical slices were obtained with a band saw and photographed. MR images and photographs were evaluated by an anatomist and radiologist. Selected 3 mm thick slices were placed in formalin and decalcified, cut, placed on large slides, and stained with hematoxylin eosin stain (HES).

RESULTS: The main adductor tendon insertions are: the anterosuperior aspect of the pubic bone for the adductor longus, the anteroinferior aspect of the pubic bone - for the adductor brevis, and the inferior aspect of the pubic bone for the adductor magnus. On histology, the adductor longus tendon fibers inserted perpendicularly into the bone at a fibrocartilage enthesis and cross connected along the anterior pubic ligament into the controlateral tendon. The rectus abdominis-pyramidalis unit was covered by a thin anterior and posterior aponeurosis. The posterior aponeurosis inserted into the superior aspect of the anterior pubic ligament, whereas the anterior aponeurosis fused distally with the adductor longus tendons.

CONCLUSION: Our findings demonstrate the insertions of the adductor tendons, on the pubic ligament and pubic bone.Histologically, the adductor longus tendon fibers inserted perpendicularly into the bone through a fibrocartilage enthesis, and cross connected along the anterior pubic ligament into the contralateral tendon.