Ultrasound-Guided Injection of the Adductor Longus and Pectineus in a Cadaver Model

Background: The close anatomic and functional relationship between the proximal parts of the adductor longus and pectineus muscles produce considerable overlap in symptoms and signs in the inguinal region. To our knowledge, there have been no publications of ultrasound (US)-guided injection techniques into the 2 muscles. Objective: This study sought to describe US-guided injection techniques in the proximal part of the adductor longus and pectineus muscles and to validate whether these techniques deliver injections appropriately to their target muscles in unembalmed cadavers. Study Design: Cadaveric study. Methods: A preliminary trial with 2 unembalmed cadavers provided information on the target sonographic structures of proximal adductor longus and pectineus muscles. Bilateral US-guided intramuscular injections in the proximal adductor longus and pectineus were performed using the remaining 5 unembalmed male cadavers. To avoid confusion of dye location, we did not inject into both the adductor longus and pectineus muscle in the same side. After injections, each specimen was dissected to evaluate the accuracy of injection. Results: Ten injections (5 for the adductor longus muscle and 5 for the pectineus muscle) were performed targeting the proximal parts of muscles in 5 cadaveric specimens. All injections were successful and blue dye was injected accurately at the target area within the adductor longus and the pectineus muscles. No other muscles were injected unintentionally. There were no accidental penetrations and/or injuries at adjacent neurovascular structures as well. Limitation: Despite successful injection of the proximal parts of adductor longus and pectineus, this study did not verify the usefulness of this technique in clinical practice. Conclusions: The results of this study may play a role in the diagnosis and management of patients presenting with chronic pelvic pain syndrome and sports hernia.