Latissimus Dorsi Transfer for Irreparable Subscapularis Tear

Abstract

The purpose of this study is to report the outcome of latissimus dorsi transfer to reconstruct an irreparable subscapularis tear. Irreparable subscapularis tears is associated with marked shoulder dysfunction and morbidity. Given the variable outcomes with pectoralis major transfer or graft augmented reconstruction, leaving many patients with a reverse shoulder arthroplasty as their only surgical option. Conversely to the pectoralis major, the latissimus dorsi (LD) line of pull is posterior to the body’s axis, in the same direction as the subscapularis. Although LD transfer has been described for posterosuperior rotator cuff tears, there is a paucity of information on LD transfer for subscapularis insufficiency. Seventy-two consecutive patients with irreparable subscapularis tears who underwent latissimus dorsi transfer. Sixteen of these patients had a prior failed latarjet and subsequently required additional bone grafting, and were excluded. Therefore, 56 patients were included in this study. The average age of 53 years (range, 37-79), with 39 (70%) males, and 30 (54%) performed in the dominant extremity. Every patient had a prior surgery, with a mean number 2 (range, 1-5). Concomitant pathologies included a supraspinatus tear in 37, upper infraspinatus tear in 11, and mild arthritis in 7 shoulders. On radiographic evaluation, 38 patients had evidence of proximal migration, while 27 had anterior subluxation. The surgical technique included open repair in 14 shoulders and arthroscopic repair in 42 shoulders. Outcome measures included visual pain analogue score (VAS), range of motion (ROM), subjective shoulder value (SSV), and Constant shoulder score. At a mean 13 months follow-up (7-51 months), patients had significant improvements in their pain, flexion, abduction, internal rotation, SSV, and Constant scores when compared to preoperatively (p<0.03). There was an improved subjective lift off test in all patients, but only 12 patients had a complete reversal of the lift off test. Belly press test improved in 43 patients, but similar to lift off, only 16 patients had a complete reversal of the belly press test. At final follow-up, 10 of 38 patients continued to have proximal migration, while 3 of 27 patients continued to have evidence of anterior subluxation. Of note, the patients with frank anterior escape had a higher likelihood of having proximal migration and anterior subluxation, but this was no statistically significant. There was no progression of arthritis stages at final follow-up. Revision surgeries included 2 patients revised to a reverse shoulder arthroplasty for rupture of the tendon transfer. Furthermore, 3 patients had LD transfer ruptures, but did not elect to undergo further surgery. Latissimus dorsi transfer for irreparable subscapularis tears has the potential to lead to clinical improvements in patients shoulder function. At final follow-up, most patients improve in many of the signs of subscapularis insufficiency, including anterior and/or proximal subluxation, clinical examination maneuvers and shoulder function. Overall, this transfer represents a reasonable option for this difficult pathology.