The arterial supply of the long head of biceps tendon: Anatomical study with implications for tendon rupture

Abstract

Zones of hypovascularity are thought to exist in several tendons of the shoulder, contributing to localized tendon weakness and subsequent rupture in clinical practice. Although these zones have been demonstrated in many frequently ruptured tendons, the existence of a similar area in the often ruptured long head of biceps (LHB) tendon is largely unknown. Twenty cadaveric upper limb specimens were dissected after injection with either a radio-opaque lead oxide/milk mixture or India ink, followed by histological sectioning of the tendons. The LHB tendon was consistently supplied via its osteotendinous and musculotendinous junctions by branches of the thoracoacromial and brachial arteries respectively. In two specimens, additional branches from the anterior circumflex humeral artery travelling in a mesotenon vascularized the midsection of tendon. These source arteries divided the LHB tendon into either two or three vascular territories, depending upon the presence of the mesotenon-derived vascular supply. A zone of hypovascularity was consistently found in the region of the LHB tendon most frequently prone to rupture. This zone covered an area 1.2-3 cm from the tendon origin, extending from midway through the glenohumeral joint to the proximal inter-tubercular groove. This hypovascular region occurred on the border of two adjacent vascular territories, where reduced caliber choke vessels provide limited arterial supply. While it is probable that the limited arterial supply contributes to the susceptibility of this area to rupture, similar to other tendons the true pathogenesis is likely to be a combination of both vascular and mechanical factors.

Disorders of the long head of biceps tendon

“…A zone of hypovascularity is found 1.2 to 3 cm from the tendon origin. 16 This zone of hypovascularity correlates with the portion of the tendon that starts intra-articularly and courses through the biceps pulley, ending near the proximal bicipital groove. 16 …”

“…LHB tendon rupture typically occurs in the hypovascular zone 1.2 to 3 cm from the tendon origin. 16 Partial-thickness rupture is often seen in association with tendinopathy and contributes to shoulder pain and dysfunction, with or without concomitant rotator cuff tear. Complete rupture of the diseased LHB tendon may actually relieve the symptoms.…”

Poly(3,4-ethylenedioxythiophene) on decellular scaffolding interrupts grafted muscle revascularization

“…One week following surgery, rats were prepared for visualization of RPNI vascularity by deposition of lead oxide (10). A lead oxide solution containing 1g of 300 Bloom Gelatin Powder (Type A Electron Microscopy Services, Hattfield, PA), 20mL tap water, along with 20g of lead oxide powder (Lead (III,IV) Oxide red 98%, (Acros Organics, Fisher Scientific, Pittsburgh, PA) was freshly prepared.…”

Assessment and treatment strategies for rotator cuff tears

“…36,37 Within this framework, the long head of biceps tendon (LHBT) passes to the sulcus: at the transition from intra-articular to extra-articular portions, there is a vascular watershed. 38 Because the intrinsic tendon vessels are accompanied by sympathetic nerve fibres, 39 damage to this portion of the LHBT is almost always accompanied by characteristic pain, 40,41 often localized to the sulcus region during motion but often diffuse in the anterior compartment of the arm at rest. The close anatomical-mechanical relationship between the strong cord of the LHBT and the two pillars of the lateral aperture of the rotator interval during respective rotation of the humeral head 42 suggests a potential feedback mechanism involving afferent information from the LHBT (under tensile load and working with the pillars) complementing that of the distal cuff tendons in determining the joint position and motion detection during the wind-up, cocking and follow-through phases of a throwing action.…”