Pedicled-lesser tuberosity osteotomy for glenohumeral joint exposure: a technical note and case report highlighting its use in allograft reconstruction of a large engaging reverse Hill-Sachs lesion after posterior shoulder dislocation

Abstract

Exposure of the humeral articular surface through an anterior approach to the shoulder for grafting humeral bone defects requires partial or complete detachment of the subscapularis tendon and traditionally is achieved through a subscapularis tenotomy, peel tuberosity osteotomy, or lesser tuberosity osteotomy. This case report presents a technique of performing a pedicled-lesser tuberosity osteotomy to allow adequate access for allograft reconstruction of a large reverse Hill-Sachs lesion after a traumatic posterior dislocation, to restore humeral head sphericity and prevent recurrent glenohumeral joint instability. The inferior subscapularis insertion is left intact leaving a periosteal sleeve and preserving the blood supply to the lesser tuberosity and humeral head, with the aim of improving healing of the osteotomy and preventing graft-related complications, such as resorption. Successful union of the pedicled-lesser tuberosity osteotomy and allograft was seen on a 6-month follow-upcomputed tomography scan, with adequate restoration of subscapularis function.

Keywords: Lesser tuberosity osteotomy; allograft; humeral head exposure; reverse Hill-Sachs lesion; shoulder instability; subscapularis.

Figure 1

Illustration demonstrating P-LTO preparation. (a) Osteotome used to make medial, superior, and lateral champher cuts. Inferior periosteal sleeve left intact. (b) P-LTO rotated inferomedially to expose vascular bed and allow exposure of humeral articular surface. (c) P-LTO rotated back before fixation. ACHA, anterior circumflex humeral artery; P-LTO, pedicled-lesser tuberosity osteotomy; RHSL, reverse Hill-Sachs lesion.

Figure 2

Axial CT scan with RHSL involving approximately 20% of humeral head articular surface. CT, computed tomography; P-LTO, pedicled-lesser tuberosity osteotomy; RHSL, reverse Hill-Sachs lesion.

Figure 3

Preoperative planning using 3D segmented models in coronal and sagittal views. (a) Overlay of the right pathologic (purple) and left mirrored (gray) humeri and (b) right pathologic humerus (purple) and personalized humeral graft (gray) computed from the left mirrored humerus. 3D, 3-dimensional.

Figure 4

The P-LTO has been created and rotated on its pedicle (currently rotated under the anteroinferior soft tissues largely out of view, as indicated by the arrow) to give excellent access to the large RHSL of the humeral head. The highly vascular bed of the P-LTO is also demonstrated. BG, bicipital groove containing long head of biceps; HH, humeral head; P-LTO, pedicled-lesser tuberosity osteotomy; RHSL, reverse Hill-Sachs lesion; ∗, vascularized bed of P-LTO; ˆ, RHSL.

Figure 5

(a) Size-matched humeral head allograft fixed with 2 headless cannulated screws. The P-LTO is visualized before being rotated on its periosteal sleeve back into its vascularized bed. (b) The P-LTO has been rotated back and fixed with 2 cancellous screws with washers as well as a double-row suture fixation from 2 medial anchors passed through the subscapularis tendon to a single lateral row anchor. arrow, P-LTO; BG, bicipital groove; P-LTO, pedicled-lesser tuberosity osteotomy; SSC, subscapularis tendon; ∗, bed of osteotomy; ˆ, allograft humeral head.

Figure 6

(a) Postoperative axial CT and (b) 3D model (superior axial view) demonstrates restoration of humeral head sphericity and union of the allograft and P-LTO. CT, computed tomography; P-LTO, pedicled-lesser tuberosity osteotomy; 3D, 3-dimensional.