Accuracy of palpating the long head of the biceps tendon: An ultrasonographic study

Objective: To determine the accuracy of palpating the long head of the biceps tendon (LHBT) within the intertubercular groove with the use of ultrasonographic localization as a gold standard. Design: Prospective, single-blinded pilot study. Setting: Sports medicine clinic at a tertiary care academic institution. Participants: Twenty-five male and female asymptomatic volunteers ages 24-41 years (mean, 30.9 ± 4.3 years) with body mass indices of 19.3 to 36.3 kg/m ² (23.84 ± 4.8 kg/m ²). Methods: Three examiners of differing experience (a sports medicine board-certified staff physician, a sports medicine fellow, and a physical medicine and rehabilitation resident) identified the LHBT location in the intertubercular groove via palpation on a subject in the supine position and marked its location by taping an 18-gauge Tuohy needle to the skin overlying the groove. The examiner order was randomized. A fourth examiner who was blinded to the palpation order assessed the previous examiner's palpation accuracy by comparing the needle position to the sonographically determined tendon position. Main Outcome Measures: Needle placement in relation to the intertubercular groove was graded as being within the groove, medial to the groove, or lateral to the groove. In the latter 2 cases, the distance from the needle to the closest groove edge was recorded. Results: Overall accuracy rate was 5.3% (4/75), ranging from 0% (0/25) for the resident to 12% (3/25) for the fellow (P ≤ .007 for interexaminer differences). All missed palpations were localized medial to the intertubercular groove by an average of 1.4 ± 0.5 cm (range, 0.3 for the fellow to 3.5 cm for the resident). Conclusion: Based on the current methodology, clinicians have a tendency to localize the intertubercular groove medial to its actual location. Consequently, clinicians should exercise caution when relying on clinical palpation to either diagnose a biceps tendon disorder or perform a bicipital tendon sheath injection. When clinically indicated, sonographic guidance can be used to accurately identify the LBHT within the intertubercular groove.