The adductor canal (AC), also known as the subsartorial or Hunter's canal, is a conical musculoaponeurotic tunnel passing through the distal portion of the middle third of the thigh. It functions as a passageway for several neurovascular structures from the femoral triangle to the adductor hiatus. The adductor canal has three borders. The vastus medialis muscle forms the anterolateral border, and the adductor longus and adductor magnus muscles form the posterolateral border. Medially, the adductor canal's border is an aponeurosis - the vastoadductor membrane, which is immediately deep to the sartorius muscle. Major structures passing through the canal include the superficial femoral artery, the femoral vein, and the saphenous nerve. Other structures, such as the nerve to vastus medialis and medial femoral cutaneous nerves, have previously been described to pass through the adductor canal, but their exact locations remain controversial. In addition to functioning as a key anatomical landmark, the adductor canal is clinically relevant. It can be a site of disease or suffer damage by trauma. It is also an increasingly-common site for the administration of regional anesthetic (nerve block) for knee, ankle, and foot surgeries.[1][2][3][4][5][6]
The adductor canal is a space located distal to the midpoint of the anteromedial thigh that functions as a tunnel for several neurovascular structures. The average length of the canal is reportedly between 8.5 to 11.5 centimeters, depending on specific study and differences in sex.[1]
Overview: The adductor canal houses the superficial femoral artery and the femoral vein.
The course of the Superficial Femoral Artery:
The course of Femoral Vein:
The saphenous nerve (SN) exits the femoral triangle at its apex and enters the adductor canal immediately lateral to the femoral artery. The saphenous nerve travels through the adductor canal until it diverges from the femoral artery distally. The saphenous nerve proceeds to exit between the sartorius and gracilis muscles.
The nerve to vastus medialis (NVM) has been previously described to travel within the adductor canal. However, other studies dispute this claim and report that the NVM travels through the subsartorial space, superficial to VAM, and deep to the sartorius muscle (see the section on clarification above). The subsartorial space also houses the subsartorial plexus, which is formed by contributions from three nerves: the medial cutaneous nerve of the thigh, the saphenous nerve, and the anterior branch of the obturator nerve.[2][7][8]
Below is a summary of the major muscles that border the adductor canal. For further detail, please see the references for each respective muscle.
Adductor Canal Block
The structures passing through the adductor canal are susceptible to multiple pathologies.
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