53 Internal Latissimus Transfer for Reverse Shoulder Arthroplasty

10.1055/b-0039-167702

53 Internal Latissimus Transfer for Reverse Shoulder Arthroplasty

Seth Gamradt and Frank Russo

Abstract

This chapter describes the anatomy and technique of a combined reverse total shoulder arthroplasty (TSA) and latissimus dorsi/teres major (LD/TM) transfer for those patients with combined pseudoparesis and loss of external rotation. Massive tearing of the rotator cuff results in active motion loss and is a debilitating condition that often warrants surgery as definitive treatment. Boileau et al have described two patterns of motion loss in patients with massive rotator cuff tears and subsequent cuff arthropathy. These authors describe the dysfunction in patients who exhibit both absent forward elevation (pseudoparesis) and absent active external rotation as combined loss of elevation and external rotation (CLEER). Retensioning the deltoid with a constrained, reversed prosthesis predictably restores forward elevation. However, lack of external rotation can persist after reverse TSA in patients with massive tears of both the infraspinatus and the teres minor. The L’Episcopo transfer was first described in 1934 for obstetric palsy. Using this technique, the LD and TM tendons are transferred posteriorly and laterally on the humerus, such that the function of the transferred muscles changes from internal rotation to external rotation. ³ In their study of 17 patients who underwent reverse TSA with LD/TM transfer, Boileau et al reported significant improvement in subjective and objective results with restoration of active forward elevation and external rotation in patients with CLEER. This procedure restores control of the shoulder in both the coronal and the sagittal planes, thereby improving spatial control of the hand to facilitate activities of daily living.

53.1 Goals of Procedure

To restore forward elevation and external rotation in those patients with combined coronal and sagittal muscle imbalances secondary to rotator cuff arthropathy.

53.2 Advantages

As opposed to a reverse arthroplasty alone, the latissimus dorsi/teres major (LD/TM) transfer combined with reverse arthroplasty can improve active external rotation in the appropriately selected patient.

53.3 Indications

Rotator cuff arthropathy with combined loss of forward elevation and external rotation.
Failed rotator cuff repair with anterior superior escape.
Failed conventional shoulder arthroplasty.
Nonunion or malunion of failed three- or four-part proximal humerus fractures.

53.4 Contraindications

Axillary nerve palsy.
Previous surgery that would make dissection of the area difficult.
Infection.
Patients who are able to maintain the arm in a minimal of neutral external rotation may not need the tendon transfer in combination with the reverse.

53.5 Anatomy

The LD acts to adduct and internally rotate the humerus. The muscle has a broad origin, from the sacrum, iliac wing, ribs 9 to 12, spinous processes of T7–T12, and inferior border of scapula. The average width of the LD tendon at its insertion measures 3.1 cm × 8.4 cm on the posterior lip of the intertubercular groove just medial to the pectoralis major and anterior to TM insertions. Given up to 30% of patients have conjoined LD and TM tendons, these tendons are often transferred together ( Fig. 53.1 ). ⁴

**Fig. 53.1** Anterior shoulder depicting the respective lengths of the tendon insertion sites with their respective neurovascular pedicles. Used with permission from Pearle AD, Kelly BT, Voos JE, Chehab EL, Warren RF. Surgical technique and the anatomic study of latissumus dorsi and teres major transfers. J Bone and Joint Surg Am. 2006; 88: 1524–1531.

The neurovascular pedicle of the LD includes the thoracodorsal artery and nerve, which insert into the anterior muscle belly roughly 13.1 cm medial from its humeral insertion. ⁴ A corresponding branch of the lower subscapular nerve inserts into the anterior muscle belly of the TM approximately 7.4 cm medial from its humeral insertion. ⁴ Each of these nerves branch from the posterior cord of the brachial plexus, and measure 13.5 and 9.3 cm in length to their respective insertions. ⁴

Structures at risk during a deltopectoral approach include the radial and axillary nerves. The radial nerve branches from the posterior cord of the brachial plexus and courses medial to the coracobrachialis and anterior to the latissimus tendon, roughly 2.4 cm medial to the humeral shaft in neutral. ⁵ This distance is variable with positioning of the humerus, measuring up to 4 cm from the insertion in 90 degrees of abduction and 45 degrees of external rotation. ⁵ Superiorly, the axillary nerve branches and wraps posteriorly around the humerus before exiting via the quadrangular space. With the arm at its side, the axillary nerve travels 1.9 cm above the superior boarder of the latissimus tendon. ⁵ However, this relationship changes similarly as above with the position of the humerus, increasing to 3.6 cm in 90 degrees of external rotation and 45 degrees of abduction ( Fig. 53.2a–c). ⁵