Introduction Overview a fairly limited approach to the shoulder, allowing little anterior exposure. Indications proximal humerus fracture-dislocations (posterior) scapula fractures scapular neck posterior glenoid rim posterior articular segments glenoid osteotomy open posterior rotator cuff repair biopsy and tumour resection Internervous plane Internervous plane between suprascapular nerve (infraspinatus) and axillary nerve (teres minor) Approach Positioning standard positioning prone alternative positioning beach chair lateral decubitus Incision classic incision curved incision starting from posterolateral lip of the acromion, extending medial along the spine of the scapula, right angle turn at the medial border of the scapula modified incision straight incision starting from posterolateral lip of the acromion, extend incision in line with the tip of scapula, incision should be parallel, and lateral, to the medial scapular border Superficial dissection incise through skin and fat identify and expose the posterior deltoid muscle belly sharply dissect deltoid muscle origin off the scapular spine and base of acrominon retract muscle distal and lateral to reveal the underlying infraspinatus and teres minor muscles Deep dissection working through the infraspinatus and teres minor interval retract teres minor inferiorly avoid injury to posterior branch of axillary nerve retract infraspinatus superiorly avoid injury to suprascapular nerve and artery deep dissection lateral identify underlying posterior glenoid capsule deep to musculature incise posterior capsule in line with muscular interval allows access to the posterior aspect of glenohumeral joint medial dissecting the infraspinatus along off the medial border of scapula retract infraspinatus muscle belly superior and lateral, as this will maintain its suprascapular neurvascular pedicle allows access to the inferior aspect of scapular body improve exposure lateral the infraspinatus tendon insertion can be tagged and cut approx. 1-2 cm lateral to its insertion on greater tuberosity retract medially medial dissection of infraspinatus off the medial border of scapula is extended superiorly to the scapular spine Dangers Suprascapular nerve anatomy passes around the base of the spine of the scapula as it runs from the supraspinous fossa to the infraspinous fossa risk of injury forceful medial and superior retraction of infraspinatus muscle Axillary nerve anatomy passes through the quadrangular space beneath the teres minor risk of injury dissection carried out inferior to the teres minor