quadrilateral space

qua·dran·gu·lar space

musculotendinous formation providing passageway for the axillary nerve, posterior humeral circumflex artery, and accompanying veins as they run from the axilla to the superior posterior arm; as the neurovascular structures enter the formation anteriorly, it is bounded superiorly by the shoulder joint, medially by the lateral border of subscapularis, laterally by the surgical neck of the humerus, and inferiorly by the tendon of latissimus dorsi; where the vessels exit the formation posteriorly, it is bounded superiorly by the teres minor, medially by the long head of the triceps, laterally by the lateral head of the triceps and inferiorly by the teres major muscle or tendon; as they emerge, most of the neurovascular structures run on the deep surface of the deltoid muscle, which they supply.
Synonym(s): quadrilateral space

quadrilateral space

An anatomic space in the upper arm and shoulder, which is defined superiorly by the teres minor, anteriorly by the subscapularis, inferiorly by the teres major and latissimus dorsi, medially by the long head of the triceps and laterally by the proximal humerus. The space contains the axillary nerve, which lies in close proximity to the inferior shoulder joint capsule and exits posteriorly around the humeral neck.
Mentioned in ?
References in periodicals archive ?
Upon traversing the quadrilateral space the nerve immediately forms an anterior and a posterior branch (9,10).
The safest and most consistent point at which to block the axillary nerve is immediately following the nerve's passage through the quadrilateral space to lie posterior to the humerus.
The quadrilateral space lies at the level of this horizontal plane (Figure 2 and 6).
The axillary nerve is vulnerable to damage in closed shoulder injuries, such as dislocation and may become involved in the quadrilateral space syndrome ((Baker & Liu 1993, Burkhead et al 1992, Cahill 1980, Cahill & Palmer 1983, Mendoza & Main 1990, Narakas 1989, Post & Grinblatt 1992, Pratt 1986, Shankwiler & Burkhead 1996, Sicuranza & McCue 1992).
Cahill BR, Palmer 1983: Quadrilateral space syndrome.
8,9) The course of the axillary nerve after it exits the quadrilateral space has been well described, (10-16) but its position in relation to the raphe has only recently been reported.
Innervation of the deltoid is from the axillary nerve, which arises from the posterior cord of the brachial plexus and passes through the quadrilateral space dividing into anterior and posterior branches.
The posterior humeral circumflex artery passes through the quadrilateral space with the axillary nerve.