Anatomical basis of Latissimus dorsi and Teres major transfers in rotator cuff tear surgery with particular reference to the neurovascular pedicles

Musculotendinous transfers (MTT) of latissimus dorsi (LD) and teres major ( TM), either in isolation or combination, have recently been advocated to tr eat irreparable rotator cuff tears. The purpose of this study was to (1) re view the anatomy of the LD acid TM neurovascular pedicles, and (2) undertak e experimental MTT to humeral insertions of either supraspinatus or infrasp inatus to evaluate tension on their nutrient arteries in six positions of t he arm. Twenty-six shoulders were studied, 22 of which had previously been injected with red latex. Cross dissection, using 4.3 x magnification when n ecessary, was followed by one MTT for each shoulder (11 LD, 6 TM, 9 combine d). The anatomy of the LD and TM neurovascular pedicles was consistent with classic descriptions in 85% of cases; "medialisation" of the thoracodorsal artery was observed in 4 specimens. Tension on the teres major artery was not observed in 15 isolated or combined MTTs, while tension on the thoracod orsal artery in at least one arm position was observed in 60% of 20 isolate d or combined MTTs. Three factors were found to be associated with tension: medialisation of the thoracodorsal artery, fixation onto the supraspinatus insertion, and 90 degrees abduction combined with internal rotation. The r esults suggest that tension on the thoracodorsal artery is possible under c ertain circumstances when an isolated LD or combined MTT is performed to tr eat irreparable rotator cuff tear.