Axillary (Anteroinferior) Approach to the Shoulder

What it exposes. The axillary (anteroinferior) approach gives direct access to the anterior and anteroinferior glenohumeral joint - the anteroinferior glenoid rim and labrum, the anterior capsule, and the subscapularis. It is the workhorse cosmetic exposure for open Bankart repair, capsular shift (capsulorrhaphy), and Latarjet coracoid transfer. Why an axillary incision (and what does not change). The whole rationale is a cosmetic scar hidden in the most dependent axillary crease. The deep dissection is the standard deltopectoral approach - only the skin incision and the subcutaneous tunnel are new. A candidate who forgets this and describes a brand-new deep plane will fail the question. The cosmetic benefit is greatest for young active patients, women and overhead athletes who are concerned about a visible chest scar.

Position. The patient is placed in the beach-chair (semi-sitting) position, seated at the side of the table so the shoulder is fully accessible, with a backrest elevated about 45 to 60 degrees. The head is secured and the arm is free-draped so it can be moved through flexion, abduction and external rotation during deep dissection - free-draping is essential. The whole anterior shoulder, the axilla and the upper chest are prepped into the field, because the incision sits in the axilla while the deep target (the coracoid and the deltopectoral interval) lies superior to it. General anaesthesia is usually supplemented by an interscalene block for post-operative analgesia. Lateral decubitus is occasionally used, but beach-chair is preferred for open anterior work. Surface landmarks to mark: - Coracoid process - the deep target; palpable about 2 to 3 cm lateral to the junction of the middle and lateral thirds of the clavicle, just inferior to the clavicle.

• Acromion and clavicle - orient the surgeon to the superior shoulder.
• Anterior axillary fold (the lower border of pectoralis major) and posterior axillary fold (latissimus dorsi and teres major) - frame the axilla.
• The axillary skin creases - the incision is placed in the most inferior (dependent) crease, where the scar is hidden when the arm is by the side.
• The deltopectoral groove - the deep target interval (this is not where the skin is cut).

Clinical assessment before surgery. Confirm the direction of instability clinically (apprehension and relocation tests, load-and-shift) and on imaging. Quantify glenoid bone loss on CT with 3D reconstruction - if it exceeds approximately 15 to 20 percent, isolated soft-tissue repair is likely to fail and a Latarjet (bony augmentation) is preferred. Assess for an engaging off-track Hill-Sachs lesion that may need addressing (remplissage, or it may push the decision toward Latarjet). Weigh patient factors (age, activity level, sport or occupation, and attitude toward a visible scar) and soft-tissue quality - hyperlaxity (Beighton score) influences whether a capsular shift is added to a Bankart repair.

Work from the axillary skin crease upward. There is no true internervous plane in the superficial dissection - the skin incision lies in the axilla and the dissection crosses only skin and subcutaneous fat. The defining step is a blunt subcutaneous mobilisation superiorly, raising a mobile skin-and-fat flap from the axillary incision up toward the coracoid. Deep to this, the standard deltopectoral internervous plane is then developed. The deep internervous plane lies between deltoid (axillary nerve) and pectoralis major (medial and lateral pectoral nerves) - the deltopectoral groove. Because the two muscles are supplied by different nerves, the plane is internervous and can be developed without denervating either muscle, and it is identical to the standard anterior shoulder approach.

Structures at risk, by layer

The axillary nerve. The axillary nerve arises from the posterior cord, passes backwards and laterally inferior to the subscapularis and the shoulder capsule, and exits through the quadrilateral space (bounded above by teres minor, below by teres major, medially by the long head of triceps, and laterally by the surgical neck of the humerus) with the posterior circumflex humeral artery. It also gives a lateral cutaneous branch to the upper arm before motor branches to deltoid and teres minor. It is endangered whenever the inferior capsule or inferior glenoid neck is dissected. Palpate it on the inferior surgical neck before inferior work, protect it with a blunt retractor placed superiorly, and never plunge instruments inferiorly. A traction injury causes deltoid denervation with shoulder abduction and external rotation weakness. The musculocutaneous nerve. The musculocutaneous nerve arises from the lateral cord, pierces coracobrachialis (which it supplies, along with biceps and brachialis), and continues distally as the lateral cutaneous nerve of the forearm. It enters coracobrachialis on average about 5 cm below the coracoid, but can lie as proximal as 1 to 2 cm in some patients. It is endangered by medial retraction of the conjoined tendon and coracoid and by retractors placed deep to the conjoined tendon. Keep retractors on bone (the coracoid or glenoid neck), avoid forceful medial retraction, and never place a retractor blindly medial to the conjoined tendon.

Subcutaneous-flap complications. The mobile axillary flap has a random blood supply, so excessively thin flaps, rough handling, prolonged retraction, or undermining that is too wide risk skin necrosis, seroma and wound dehiscence - the principal soft-tissue disadvantage of the approach. Prevent these with a thick flap (fat kept on its deep surface), gentle handling, limited retraction time, and meticulous haemostasis. A seroma in the subcutaneous pocket is managed conservatively; rarely it requires aspiration. How to extend the approach. The proximal or superior deltopectoral interval can be extended toward the coracoid and clavicle for greater exposure (coracoid osteotomy in Latarjet, rotator-interval work), and the subcutaneous tunnel can be lengthened superiorly - but the skin window is limited by the cosmetic incision. Distal extension is limited and is the principal disadvantage: the cosmetic axillary incision cannot be extended distally along the deltopectoral groove without sacrificing the cosmetic result. If extensive distal or anterior humeral exposure is required, abandon this approach for a standard deltopectoral incision. If exposure proves inadequate intra-operatively, the incision can be extended (converting to a standard deltopectoral incision), but this loses the cosmetic advantage - so patient selection and pre-operative planning are essential.

Closure. Repair the capsule (if a capsulotomy or capsular shift was performed) with absorbable sutures, and repair the subscapularis if it was tenotomised or peeled (to the lesser tuberosity through bone tunnels or suture anchors); if it was only split, close the split. Re-approximate the deltopectoral interval loosely with absorbable suture so as not to constrain the cephalic vein, and achieve meticulous haemostasis of the subcutaneous pocket. Close the subcutaneous tissue in layers to obliterate dead space in the tunnel and reduce seroma, then close the skin with a running subcuticular monofilament suture (the whole point of the approach) - dermal adhesive may supplement. A drain is rarely required; if used, remove it early. Apply a sling or shoulder immobiliser with the arm in internal rotation. Post-operative care. Sling or immobiliser for the period dictated by the procedure (typically 4 to 6 weeks for a Bankart or capsular shift, protecting external rotation). Phased physiotherapy: pendulums and passive motion first, then active motion, then strengthening; restrict external rotation in abduction early to protect the repair. Return to contact sport is typically 6 to 9 months after stabilisation, once strength and motion are restored. Review the wound at 10 to 14 days.

The axillary approach provides access to the anterior and anteroinferior glenohumeral joint and is used for: - Open Bankart repair - reattachment of the avulsed anteroinferior labrum and capsulolabral complex to the glenoid rim (anchors or transosseous), the classic operation for recurrent anterior dislocation with a Bankart lesion and acceptable bone stock.

• Latarjet coracoid transfer - the related procedure; transfer of the coracoid process (with its attached conjoined tendon) to the anteroinferior glenoid neck to restore the bony arc and provide a sling effect, used when glenoid bone loss is significant (approximately greater than 15 to 20 percent) or there is bipolar bone loss with an engaging Hill-Sachs lesion.
• Capsular shift or capsulorrhaphy - tightening of a redundant capsule (an inferior capsular shift, medial or lateral shift, or T-capsulorrhaphy) for capsular laxity and anteroinferior or multidirectional instability.
• Combined Bankart and capsular shift - for instability with both a labral tear and capsular redundancy.
• Rotator interval closure - adjunctive tightening for inferior or superior laxity.
• Removal of loose bodies and limited synovectomy within the accessible anterior joint.
• Historical soft-tissue reconstructions (Putti-Platt, Magnuson-Stack) - largely superseded but performed through the same anterior exposure.

Guidelines, Registries & Global Practice Anterior shoulder stabilisation is practised worldwide and is examined across advanced orthopaedic practice or advanced orthopaedic practice, DNB or MS, MRCS and SICOT. Globally convergent principles guide the use of an open anterior (cosmetic axillary) approach: confirm the direction of instability, quantify glenoid bone loss on CT, and reserve isolated soft-tissue reconstruction (Bankart with or without a capsular shift) for instability with a Bankart lesion and bone loss below the critical threshold (roughly 15 to 20 percent), while selecting coracoid transfer (Latarjet) when bone loss is significant or bipolar. The choice of skin incision (a visible deltopectoral scar versus a hidden axillary crease scar) is a cosmetic decision that does not change the deep surgical technique, the internervous plane, or the structures at risk. Side-by-side principles (where guidance converges): | Body | Position on anterior stabilisation and approach |

|------|--------------------------------------------------| | ISAKOS or ASES international consensus | Bone loss greater than approximately 13.5 to 20 percent (the glenoid track or bipolar concept) favours bony augmentation (Latarjet) over isolated Bankart repair; soft-tissue repair preferred when bone loss is below this threshold | | BOA or BOAST (UK) | Document instability direction and bone loss; counsel patients on recurrence rates and the option of arthroscopic versus open repair; shared decision-making on scar | | AAOS (US) | Indication-based selection: traumatic anterior instability with a Bankart lesion and acceptable bone stock - repair; significant glenoid deficiency - bony augmentation | | AO Foundation | Standard deltopectoral deep interval for open anterior work; protect the axillary and musculocutaneous nerves; repair capsule and subscapularis in layers | Global practice variation. In high-resource settings, arthroscopic Bankart repair is now the default for soft-tissue-only instability, with open (including cosmetic axillary) approaches reserved for cases needing a capsular shift, a Latarjet, or revision. In resource-limited settings, open Bankart repair through a standard or cosmetic anterior incision remains a durable, implant-light option. The cosmetic axillary incision is a refinement available wherever the soft-tissue envelope is healthy and the surgeon is familiar with subcutaneous tunnelling; it is not appropriate in revision cases with previous anterior scarring or compromised axillary skin. Consent (globally applicable). Discuss recurrence of instability (higher in young contact-sport athletes and in bone loss), stiffness and loss of external rotation (typically a small loss after stabilisation), axillary nerve injury with deltoid weakness, wound and flap complications (seroma, skin necrosis) for the axillary incision, infection, and the small risk of recurrence requiring revision.