Update on lateral and medial spaces of the dorsal wall of the axillary fossa

Lateral and medial axillary spaces (also named quadrilateral and triangular spaces) correspond to orifices of the posterior wall of axillary fossa communicating with deltoid and scapular areas. We attempt to become clear the anatomic boundaries of these spaces and the structures passing through. We studied by dissection 18 fresh and embaulmed human upper limb of both sex. Lateral axillary space was limited by lateral edge of the long head of the triceps muscle medialy, the medial edge of the surgical neck of the humerus lateraly. The tendon of teres major and latissimus dorsi muscles constituted lower limit and the superior boundary was the scapulohumeral capsule rather than the teres minor muscle. Structures passing through the quadrilateral space where the axillary nerve and the posterior humeral circumflex vascular pedicle. Boundaries of the triangular space where, lateraly the medial edge of the long head of the triceps, superiorly the inferior edge of the teres minor and the axillary border of the scapula; the upper edge of the teres major corresponded to the superior limit. Abduction of the upper limb is a movement which increase the risk of entrapment phenomenon of the axillary nerve in relation to rigid anatomic structures like the surgical neck of the humerus, the scapulohumeral capsule and the tendon of latissimus dorsi and teres major muscles. Neverless genetics cause of anatomic predisposition is evocated in the quadrilatere space syndrome.