The aim of this study was a better understanding of the role of the va
scular supply as a pathogenic factor in rotator cuff disease. Twenty-f
ive shoulders from unembalmed cadavers were studied after injection of
the upper limb aa. with barium sulfate. The predominant arteries were
the vessels of the subscapularis m. These branches originated from th
e axillary a. the anterior circumflex humeral a., and the posterior ci
rcumflex humeral a. The supraspinatus m. was supplied by the suprascap
ular a but the acromial branch of the thoracoacromial a. supplied the
tendon of the supraspinatus. The infraspinatus and teres minor tendons
were vascularised by the ascending branches of the posterior circumfl
ex humeral a. The tendon of the long head of the biceps brachii m. was
supplied by a branch termed the ''arcuate artery'' [7] and by a branc
h we describe derived from the brachial a. at the level of the latissi
mus dorsi tendon and travelling in a true mesotendon. There is a very
real critical zone, with a lesser blood-flow, 1.5 cm from greater tube
rcle, situated mainly at the supraspinatus tendon. This is a convergen
ce zone of the anterior and posterior circumflex humeral aa., the supr
ahumeral a. [14] and the thoracoacromial a. The histologic studies con
firmed the poor vascularity of this critical zone.