Subsartorial Compartments and Membranes in the Adductor Canal:Morphological, Histological and Immunohistochemical Study

Background: The precise description of the adductor canal and its containing membranes has become an issue of great surgical and clinical importance. Neurovascular entrapment within the adductor canal may simulate many clinical conditions for cases presented with medial knee or leg pain and ischemic manifestations of the leg.
Aim of the work: The The aim of the present work was to spotlight on the subsartorial fascial compartments in the adductor canal and to elucidate the morphological, histological and immunohistochemical features of the containing membranes. Materials and Methods: Forty thigh specimens, pertaining to 15 embalmed and 5 fresh human adult cadavers (15 males, 5 females) were dissected in pursuit of this aim. Trichrome staining and immunohistochemical staining using skeletal muscle actin mouse monoclonal antibody were used to elucidate the structure of these membranes.
Results: Thick pentagonal vastoadductor membrane (VAM), distally, and thin triangular vastofemoral membrane (VFM), proximally, roofing two corresponding fascial tunnels and the subsartorial space superficial to them were observed. The mean length of VAM and VFM were 7.9 and 7.8 cm respectively. The VAM stretched between the vastus medialis (VM) and the adductor magnus (AM) and longus muscles and overlaid the saphenous nerve, its subsartorial and lower medial femoral cutaneous branches, femoral vessels, one to three arterial pedicles for the sartorius, one pedicle for the vastus medialis muscle and descending genicular vessels. The VAM originated from the tendinous fibres of the adductor magnus
tendon and constantly spread anterolaterally. The arterial pedicles to sartorius muscle, the lower medial femoral cutaneous and the subsartorial branches of the saphenous nerve constantly pierced the VAM. An arterial pedicle to the vastus medialis muscle and perforating veins between the superficial veins and the femoral vein proved to pierce the VAM in 8/40 specimens. The VFM stretched between the femoral artery and the VM muscle and overlaid the femoral vessels, the saphenous nerve, nerve to the VM and an arterial pedicle for VM. It was pierced constantly by two arterial pedicles to the sartorius muscle and occasionally (20/40 specimens) by a communicating nerve between the saphenous and the medial femoral cutaneous nerves. Trichrome staining of the VAM revealed that it consisted of three superimposed layers of collagen bundles, appeared in oblique and longitudinal directions and having the same structural configuration and
continuous with the tendinous fascia overlying the AM muscle. The VFM was formed of multiple thin transversely-cut collagen bundles. Immunohistochemical study proved the absence of the skeletal muscle fibres in both membranes as proved by negative immunoreaction. Conclusions: The morphological and histological features of these subsartorial membranes may help the physicians to improve the management techniques of various clinical cases.