Long head biceps tendon

Long head biceps tendon

MR evaluation of the intra-articular segment of the long head biceps tendon (LHBT) is best carried out on both oblique sagittal and oblique coronal images, while the extra-articular segment is best evaluated on axial images. The LHBT tendon is covered with a synovial sheath connected with the joint space along its course within the bicipital grove. Therefore, fluid signal around the tendon may be seen in cases of joint effusion, nevertheless in proportionate amount, and should not be mistaken for tenosynovitis. Tenosynovitis of the LHBT is diagnosed if fluid is detected around the tendon only or if the amount of fluid around the tendon is clearly out of proportion to that in the glenohumeral joint. Tendinosis of the LHBT is suspected when focal thickening and high signal (but less than that of fluid) of the tendon or part of it is noted, usually associated with fluid signal within the synovial covering. The most commonly affected part is the supra-humeral portion or the horizontal part and it may be a result of impingement. Tears of the LHBT vary from partial to complete tear to tendon avulsion. Tears appear as focal areas of high signal intensity, similar to that of fluid on T2-weighted images. Avulsion is diagnosed by noting the absence of the intra-articular segment of the tendon with no signs of dislocation. A dislocated LHBT is often medially displaced, and is commonly associated with subscapularis tendon tear.

Subscapularis tendon avulsion with long head of biceps tendon dislocation. A: Axial T1-weighed image; B: Axial gradient-recalled echo image; C: Coronal oblique T1-weighted images showing avulsion of the subscapularis tendon (asterisk in B) with muscular atrophy and long head biceps tendon dislocation (arrows) with diffuse tendinous thickening and high signal.