Posterosuperior (PS) labral tear can occur in patients with repetitive overhead activity of the shoulder, as overhead activity may provoke repetitive shearing of the humeral head against the PS labrum.1 Although arthroscopy has been the golden standard diagnostic method of glenoid labral tear to date, its application is limited because of its invasiveness. Magnetic resonance arthrography is another useful tool. Despite its high diagnostic accuracy for the glenoid labral tear, performing arthroscopy and magnetic resonance arthrography may be limited because of their invasiveness and high cost. Recently, a few studies showed the possibility of ultrasonography (US) as a useful method to diagnose PS labral tear.2,3 Given that US can be performed in real time, it has an advantage in diagnosing PS labral tear by performing dynamic US with a specific motion inducing pain. Despite such advantages, there has been no report regarding the diagnosis of PS labral tear by identifying labral detachment using dynamic US. Therefore, we report a patient with PS labral tear, which was diagnosed by identifying labral detachment in dynamic US.
A 60-yr-old, right-handed man reported right shoulder pain for 1 mo. He complained of posterior shoulder pain with clicking sensation during abduction and external rotation (ABER) stress test. Pain started after excessive ABER of the shoulder during dumbbell lifting. The initial level of pain at the posterolateral shoulder was rated at 6 of 10 on a numeric rating scale. There was no limitation on the motion of the shoulder joint, but there was posterior joint-line tenderness and pain at the end range of external rotation. The O’Brien test was positive. Posterosuperior shoulder pain was induced by posterior apprehension test and relieved by relocation test. However, other tests, such as Hawkins-Kennedy test, Neer test, Yegason test, and adduction stress test, were negative. The patient was initially advised to undergo magnetic resonance arthrography for the evaluation, but he refused it because of the high cost. After obtaining the consent from the patient, US was performed with the patient sitting down in front of the examiner. Initially, conventional US scanning of PS labrum was performed with the patient’s arm passively adducted and internally rotated with an elbow flexion of 90 degrees. Then, a dynamic US was performed by passively abducting and externally rotating the patient’s arm. Posterosuperior labral detachment, in addition to Hill-Sachs lesion, and capsular detachment of the labrum away from the shoulder joint capsule, was visible (Fig. 1). Patient’s symptom was deemed secondary to this PS labral injury. With such dynamic US findings and physical examination, the patient was diagnosed with PS labral tear (Video 1).
Such findings may only be found in ABER motion; therefore, it may be helpful to consider adding dynamic ABER position examination in clinical scenario suspicious for PS labral tear. In conclusion, dynamic US with ABER motion may be helpful to physicians when diagnosing and treating patients with PS labral tear, if arthroscopy or magnetic resonance arthrography is not possible.
1. Budoff JE, Nirschl RP, Ilahi OA, et al.: Internal impingement in the etiology of rotator cuff tendinosis revisited. Arthroscopy
2. Park D: Clinical characteristics of patients with posterosuperior labral tear: a comparison with patients with other shoulder disorders. J Pain Res
3. Park D: Evaluation of posterosuperior labral tear with shoulder sonography after intra-articular injection: a case series. Am J Phys Med Rehabil