Posterior dislocation of long head of biceps tendon following traumatic anterior shoulder dislocation: imaging and intra-operative findings

Abstract

A case of posterior dislocation of the long head of biceps tendon, a rare occurrence following traumatic anterior glenohumeral dislocation, along with complete rotator cuff rupture and large haemarthrosis is presented with imaging and intra-operative findings. The interposed tendon prevented complete reduction. Appearances at MRI were diagnostic and directed the surgical approach.

Keywords: MRI; Posterior dislocation long head biceps tendon; failed glenohumeral reduction; traumatic anterior glenohumeral dislocation.

Figure 1

69 year old male presenting with traumatic anterior glenohumeral dislocation. Findings: the humeral head is seen to lie inferior to the coracoid process (asterisk) consistent with anterior shoulder dislocation. No definite fracture is seen. Technique: AP radiograph.

Figure 2

69 year old male with traumatic anterior glenohumeral dislocation. CT performed after failed attempts at reduction. Findings: a) axial image shows anterior subluxation at the glenohumeral joint, black asterisk marks humeral head. The course of infraspinatus is disrupted by a soft tissue “mass” posteriorly (posterior white asterisk) - a haemarthrosis within which lies a tiny avulsion fracture (arrow). b) Posterolateral view of a 3D volume reconstruction showing the relationship of the humerus to the glenoid fossa (asterisk). Technique: Unenhanced MDCT, 125 mAs, 120kV, slice thickness 1mm, increment 0.5 mm (Brilliance CT 64-channel, Philips, Surrey, UK).

Figure 3

69 year old male with traumatic anterior glenohumeral dislocation with failed reduction after multiple attempts, complete rotator cuff tear, posterior dislocation long head of biceps tendon and haemarthrosis. Findings: a) There is an abnormal course of subscapularis with the disrupted tendon insertion folded into the anterior joint space (black arrow). A haemarthrosis with fluid-fluid levels is seen posterior to the joint. The tiny avulsion fracture, (white arrowhead) seen as a small hypointense focus lies posterolaterally. b) Disrupted subscapularis tendon and teres minor tendon are seen (anterior and posterior black arrows). The long head of biceps tendon has slipped over the greater tuberosity and lies posterior to the humeral head (white arrow). c) Disrupted teres minor insertion is demonstrated (black arrow). The dislocated long head of biceps tendon lies against the lateral aspect of humerus (white arrow). Short head of biceps can be seen (white arrowhead). d) The dislocated long head of biceps tendon is lying abnormally laterally at a more inferior level (white arrow). Technique: Axial gradient echo MRI a–d cranial to caudal 1.5T; TR/TE/Flip angle: 1300ms/27ms/30 degrees; FOV 200; matrix 410 × 512; slice thickness 4 mm.

Figure 4

69 year old male with traumatic anterior glenohumeral dislocation with failed reduction after multiple attempts, complete rotator cuff tear, posterior dislocation long head of biceps tendon and haemarthrosis. Findings: a) The long head of biceps tendon can be seen at its origin on the superior glenoid (white arrow).There is a full-thickness tear of supraspinatus with retraction (black arrow). b) The intra-articular portion of the long head of biceps tendon is seen (white arrow). c) The long head of biceps tendon is lying posteriorly with respect to the bicipital groove (white arrow). d) The long head of biceps tendon can be seen dislocated posterior to the humerus (white arrow). Technique: Coronal oblique STIR anterior to posterior a–d 1.5T; TR/TE/time to inversion: 4290ms/29ms/130ms; FOV 160; matrix 394 × 512; slice thickness 4 mm

Figure 5

69 year old male with traumatic anterior glenohumeral dislocation with failed reduction after multiple attempts, complete rotator cuff tear, posterior dislocation long head of biceps tendon and haemarthrosis. Findings: a) The long head of biceps tendon is seen just lateral to its origin (white arrow). The musculotendinous portions of the rotator cuff: supraspinatus, infraspinatus and teres minor are seen in a clockwise direction (black arrows). b) The posteriorly dislocated long head of biceps tendon (white arrow) is seen. Torn, retracted supraspinatus demonstrated (superior black arrow) while infraspinatus and teres minor are stretched posteriorly due to the haemarthrosis (further black arrows). c) The posteriorly dislocated long head of biceps tendon is again seen (white arrow). Supraspinatus and infraspinatus are no longer seen. Torn teres minor is demonstrated (black arrow). d) The long head of biceps tendon is seen wrapping round the humeral shaft to come anteriorly (white arrow). No rotator cuff tendons are now visualised. Technique: Sagittal oblique proton-density medial to lateral a–d 1.5T; TR/TE: 3570ms/15ms; FOV 160; matrix 512 × 512; slice thickness 4 mm

Figure 6

69 year old male following traumatic anterior glenohumeral dislocation with complete rotator cuff tear, posterior dislocation long head of biceps tendon and haemarthrosis at MRI. Intra-operative image seen as if from above, pre-reduction following removal of the haemarthrosis where tenotomy of long head of biceps tendon and rotator cuff repair were subsequently performed. Findings: 1) The exposed articular surface of the humeral head secondary to rotator cuff tear is seen. The humeral head remains anteriorly translated relative to the glenoid (and long head of biceps origin). 2) Posteriorly displaced long head of biceps tendon is shown by the Langenbeck retractor. 3) Supraspinatus footprint region. 4) Deltoid muscle (reflected during exposure) 5) Acromion is here. 6) Line of the bicipital groove and hence anatomical position of long head of biceps tendon. Technique: Superior strap approach with deltoid split.