Are palpation-guided interventional procedures on the adductor longus muscle safe? A cadaveric and sonographic investigation.

Purpose: The main objective was to study the anatomy of the adductor longus by ultrasound and cadaveric dissection, correlate the findings with the different approaches described, and evaluate the feasibility of defining a "safe window" for interventional musculoskeletal procedures.

Methods: The anatomical study was performed on six cadaveric pieces, while ultrasound evaluations were performed on both lower limbs of 26 subjects (n = 52). Ultrasound variables included the number of saphenous veins, the location of the saphenous vein in relation to the proximal myotendinous junction, the number of vessels within or superficial to the adductor longus, and the distance between the dermis and the inferior border of the adductor longus to the anterior branch of the obturator nerve.

Results: Key anatomic risk factors identified in cadavers included the great saphenous vein, the anterior branch of the obturator nerve, and the vascular network traversing the adductor longus. Ultrasound findings revealed that 91.4% of cases had at least one vessel at the proximal myotendinous junction in the cross-sectional area, almost 60% showed two to five vessels within the thickness of the muscle, and the anterior branch of the obturator nerve was located at a mean depth of 3.63-3.93 cm.

Conclusions: It was not possible to define a "safe" approach area without the risk of damaging any neurovascular bundle due to the high anatomical variability both in number and in the route of these along the adductor longus. Therefore, the use of ultrasound to guide any interventional musculoskeletal procedure is highly recommended.