Anterolateral approach to the shoulder

The anterolateral approach to the shoulder provides excellent exposure of the acromioclavicular joint, the coracoacromial ligament, and the supraspinatus tendon. It is commonly used for:

1. Rotator cuff repair
2. Long head of the biceps repair
3. Acromioclavicular joint decompression
4. Anterior shoulder decompression

The use of arthroscopic subacromial decompression has reduced the need for this approach in treating impingement syndrome and, in some cases, rotator cuff repair. However, the anterolateral approach to the shoulder remains clinically relevant for many patients with extensive degenerative rotator cuff disease.

Patient Positioning

The patient is placed supine on the operating table in a beach-chair position. A sandbag is positioned under the spine and the medial border of the scapula to bring the affected side forward.

Landmarks and Incision

Landmarks:

• Coracoid process
• Acromion

Incision:

Make a transverse incision starting at the anterolateral corner of the acromion and ending just lateral to the coracoid process.

Internervous Plane

There is no internervous plane for the anterolateral approach to the shoulder (the deltoid muscle is split proximal to the axillary nerve).

Superficial Dissection

The superficial fascia is identified and incised. Numerous superficial vessels are present; these must be managed to improve visualization. The deltoid muscle is then sharply released from the acromion or clavicle, depending on the area requiring surgical intervention. This release should be limited, as deltoid repair is often challenging. The acromial branch of the thoracoacromial artery must be ligated when encountered deep within the deltoid muscle, near the acromioclavicular joint.

Deep Dissection

The coracoacromial ligament is then released from the acromion. It can also be removed by detaching it from the coracoid. The subacromial bursa is now visible and can be excised to reveal rotator cuff pathology.

Approach Extension

The anterolateral approach to the shoulder cannot be extended proximally or distally.

Dangers

Structures at risk during the anterolateral approach to the shoulder include:

1. Axillary nerve: This nerve runs transversely across the surface of the deltoid muscle, approximately 7 cm distal to the acromion.
2. Acromial branch of the thoracoacromial artery: It runs directly beneath the deltoid muscle.

References and Further Reading

1. Surgical Exposures in Orthopaedics – 4th Edition
2. Mouraria GG, Zoppi A, Kikuta FK, Moratelli L, Cruz MA, Etchebehere M. ANTEROLATERAL APPROACHES FOR PROXIMAL HUMERAL OSTEOSYNTHESIS: A SYSTEMATIC REVIEW. Acta Ortop Bras. 2019 May-Jun;27(3):178-182. doi: 10.1590/1413-785220192703215572. PMID: 31452617; PMCID: PMC6699402.
3. Hettrich CM, Paul O, Neviaser AS, Borsting EA, Lorich DG. The anterolateral approach to the proximal humerus for nonunions and delayed unions. Int J Shoulder Surg. 2011 Jan;5(1):21-5. doi: 10.4103/0973-6042.80466. PMID: 21660194; PMCID: PMC3109769.
4. Kongcharoensombat W, Wattananon P. Risk of axillary nerve injury in standard anterolateral approach of shoulder: Cadaveric study. Malays Orthop J. 2018 Nov;12(3):1-5. doi: 10.5704/MOJ.1811.001. PMID: 30555639; PMCID: PMC6287134.