A Rare Case of Rotator Cuff Interposition Causing Humeral Head Subluxation Following Anterior Shoulder Dislocation

Abstract

This case report aims to highlight that not all shoulder dislocations are simple to treat and that early recognition of complications is key in managing these injuries successfully. We report the case of a 68-year-old gentleman who presented to Accident and Emergency (A&E) following a fall and sustaining an anterior dislocation of his right shoulder. This was reduced under sedation; however, the patient had an ongoing feeling that his shoulder "was not right." The subsequent investigation demonstrated persistent anterior subluxation of the humeral head with rotator cuff interposition in the glenohumeral joint. This case appears to be the first of its kind to be reported in which the supraspinatus, subscapularis, and long head of biceps were collectively interposed. This was treated operatively with open reduction and rotator cuff repair, even though the procedure was technically difficult due to tissue fibrosis and the formation of adhesions. The patient progressed well and had a good clinical outcome. This case highlights that rotator cuff interposition following shoulder dislocation is a rare but debilitating complication and is often neglected in initial care. We must recognise that patients are their own experts, and if they report something is "not right," further investigation and prompt treatment are required.

Keywords: complication; dislocation; open reduction; rotator cuff; shoulder; shoulder dislocation; shoulder pathology; soft tissue impingement; trauma.

Figure 1. Anteroposterior radiograph of the right shoulder. The arrow indicates anterior dislocation of the humeral head.

Figure 2. (A) Anteroposterior radiograph of the right shoulder. (B) Lateral Y-view of the right shoulder. The arrows indicate the reduction of the humeral head into the glenoid fossa.

Figure 3. (A) Anteroposterior radiograph of the right shoulder. (B) Lateral Y-view of the right shoulder. The arrows demonstrate anterior subluxation of the humeral head in the glenoid fossa.

Figure 4. Axial magnetic resonance image of the right shoulder.

Figure 5. Axial magnetic resonance image of the right shoulder.

Figure 6. Coronal magnetic resonance image of the right shoulder.

Figure 7. Image demonstrating the humeral head button-holed through the subscapularis muscle.

(α) Humeral head. (β) Deltoid muscle. (γ) Subscapularis muscle.

Figure 8. Displaced anatomy identification.

(α) Bicep tendon. (β) Subscapularis tendon.

Figure 9. Displaced anatomy identification.

(α) Supraspinatus tendon. (β) Humeral head.

Figure 10. Supraspinatus muscle repair with the use of a bone anchor.

(α) Supraspinatus muscle. (β) Bone anchor fixation of the supraspinatus.

Figure 11. Postoperative radiographs. Arrows indicate in-situ bone anchors in the humeral head. (A) Anteroposterior radiograph of the right shoulder. (B) Lateral Y-view of the right shoulder.