Usefulness of ultrasound in diagnosing long head of the biceps tendon malposition in patients with rotator cuff tears

Is It Time to Rethink the Relationship Between Subscapularis Tears and the Long Head of Biceps Tendon?

Introduction Pre-operative diagnosis of subscapularis tears remains a difficult challenge. Ultrasound has been shown to be ineffective at directly detecting subscapularis tears. It has been widely accepted that medial subluxation of the long head of biceps tendon (LHBT) is associated with full-thickness subscapularis tears. The aims of this study are to assess whether LHBT subluxation on ultrasound scanning has any predictive value for subscapularis tears and to determine the relationship between LHBT subluxation and subscapularis tears at arthroscopy. Methods Pre-operative ultrasound and arthroscopic findings for patients undergoing arthroscopic rotator cuff repair at our institution between March 2011 and January 2016 were analysed. The accuracy of LHBT subluxation on ultrasound and at arthroscopy as a predictor of subscapularis tears at arthroscopy was calculated. The correlation between LHBT subluxation and subscapularis tears was determined. A standardised technique was used for ultrasound scans, and the grade of the sonographer was recorded. Results Three hundred fifty-nine rotator cuff repairs were performed. Twenty-four patients had a subluxed LHBT. Ultrasound was poorly sensitive (50%), and a subluxed LHBT on ultrasound only correlated very weakly with subscapularis tears at arthroscopy (R = 0.268, p<0.001). At arthroscopy, 92 patients had full-thickness subscapularis tears. Of these, only 16 patients (17%) had a subluxed/dislocated LHBT. Of the 24 patients with a subluxed LHBT, eight had no subscapularis tears. Thus, LHBT subluxation/dislocation only correlated weakly with full-thickness subscapularis tears (R=0.252, p<0.001). Conclusion Due to their close anatomical relationship, traditional teaching suggests subscapularis tears are associated with medial LHBT subluxation. Our data indicate that, contrary to popular belief, the two are only weakly correlated. In our series, the majority of patients with subscapularis tears (83%) had their LHBT in-groove. The authors therefore recommend high vigilance during arthroscopy for the diagnosis and repair of subscapularis tears, regardless of pre-operative ultrasound findings and the intra-operative position of the LHBT.

Point-of-care ultrasound in musculoskeletal field

The musculoskeletal field is relatively new in point-of-care ultrasound (POCUS), a modality that has been gaining significance with the evolution of ultrasound (US) equipment and high-frequency probes. Images have become progressively clearer over the past decade, making it possible to diagnose many pathological conditions without exposure to radiation. Ultrasonography reveals many soft tissue pathologies that cannot be visualized using plain radiographs, which have historically been the first choice for the evaluation of musculoskeletal disorders. US saves money and time compared to magnetic resonance imaging (MRI). Although it is difficult to diagnose a disorder inside bone, its surface can be visualized very clearly, and it is also possible to visualize cartilage. Furthermore, with POCUS, it is possible to confirm a disorder and the continuity of the fibrous structures of muscles, tendons, and ligaments. In addition, the understanding of pathological conditions of motor disturbances, such as nerve or muscle/tendon injury, nerve paralysis, adhesions of the tendons, and joint instability, is deepened by observing the movement of these structures. Peripheral nerves, even small branches, can be visualized, and pathological conditions can be pinpointed by observing the nerve morphology, continuity, and relationship with the surrounding tissues. Children can be examined in a safe, relaxed environment, without leaving their parents. In addition, US is significantly different from other modalities in that it can be used for both diagnosis and treatment. Being able to visualize target sites improves safety and route accuracy of needle insertion for injection or puncture. Musculoskeletal POCUS is indispensable in routine medical care and is a technique that medical residents should acquire.