This cadaveric study dissected 30 shoulders to map the branching pattern of the axillary nerve. It characterizes where the nerve divides, which branches supply which muscles, and the surgical landmarks for the posterior approach. The goal is safer shoulder surgery and better planning for selective nerve transfers.
When you approach the shoulder posteriorly, the posterolateral corner of the acromion is your anchor. The axillary nerve sits a mean 7.8 cm away, so plan deltoid splits and hardware placement with that danger zone in mind.
The branching hierarchy is testable and clinically useful. The posterior branch always feeds teres minor first, then posterior deltoid, then becomes the superior lateral cutaneous nerve. The anterior branch reliably supplies the anterior and middle deltoid.
This matters for nerve transfer planning. Procedures like transferring the branch to the long head of triceps into the anterior branch depend on knowing exactly which fascicle drives which muscle.
The practical trap: posterior deltoid innervation is variable. Only 70% comes purely from the posterior branch. If you cannot trace a branch back to the trunk, you cannot assume which division it belongs to.
This cadaveric study dissected 30 shoulders to map the branching pattern of the axillary nerve. It characterizes where the nerve divides, which branches supply which muscles, and the surgical landmarks for the posterior approach. The goal is safer shoulder surgery and better planning for selective nerve transfers.
When you approach the shoulder posteriorly, the posterolateral corner of the acromion is your anchor. The axillary nerve sits a mean 7.8 cm away, so plan deltoid splits and hardware placement with that danger zone in mind.
The branching hierarchy is testable and clinically useful. The posterior branch always feeds teres minor first, then posterior deltoid, then becomes the superior lateral cutaneous nerve. The anterior branch reliably supplies the anterior and middle deltoid.
This matters for nerve transfer planning. Procedures like transferring the branch to the long head of triceps into the anterior branch depend on knowing exactly which fascicle drives which muscle.
The practical trap: posterior deltoid innervation is variable. Only 70% comes purely from the posterior branch. If you cannot trace a branch back to the trunk, you cannot assume which division it belongs to.