Deltopectoral approach to the shoulder

The deltopectoral approach to the shoulder (also known as the anterior approach) is utilized for the following procedures:

Shoulder arthroplasty.
Proximal humerus fractures (particularly 3- and 4-part fractures).
Reconstruction for recurrent dislocations.
Long head of the biceps tendon injuries.
Septic glenohumeral joint.
Tumor biopsy and excision.

Patient Positioning

Beach Chair Position:

The head is secured in a Mayfield headrest or a standard beach chair attachment.
The torso is elevated 30 to 60 degrees depending on the procedure; this can cause temporary hypotension.
The opposite arm, both legs, and other bony prominences are padded and secured.
The operative shoulder and arm are positioned off the side of the table to ensure full access.
Placing a bump under the ipsilateral scapula can improve exposure.
Rotating and tilting the bed away from the surgical side may be helpful. Commercial arm holders or positioning aids can also be beneficial.

Landmarks and Incisions

Landmarks:

Coracoid process.
Deltopectoral groove.

Incision:

Extended Deltopectoral Incision: Typically used for arthroplasty and fracture fixation. A 10 to 15 cm oblique incision is made just lateral to the coracoid process, extending to the deltoid insertion.

Limited Anterior Incision: Typically used for coracoid bone block transfers or open capsulorrhaphy. A 5 cm vertical incision is made from the coracoid process downward toward the axillary crease. This incision can be extended superiorly for better visualization.

Internervous Plane

The internervous plane for the deltopectoral approach lies between:

The deltoid muscle, innervated by the axillary nerve.
The pectoralis major muscle, innervated by the medial and lateral pectoral nerves.

Superficial Dissection

Identify and dissect the deltopectoral interval:

The cephalic vein is the key landmark.
Identification can be easier distally. Helpful clues include the orientation of muscle fibers (deltoid fibers are more vertical, pectoralis fibers more horizontal), a visible groove, and perivascular fat.
The vein is typically easier to dissect away from the pectoralis major and retract laterally with the deltoid muscle.
Small tributaries should be coagulated.
A large branch often crosses the superior aspect of the incision and may require ligation with a suture.

Retract the deltoid laterally and the pectoralis major medially:

Commercial self-retaining retractors are helpful.
A superiorly placed retractor over the coracoid process can also be useful.
Make an incision in the clavipectoral fascia, lateral to the conjoined tendon.
Start proximally at the coracoacromial ligament and continue distally to the inferior aspect of the subscapularis tendon.
The clavipectoral fascia can be identified as the structure that moves when the arm is internally and externally rotated.

Deep Dissection

The short head of the biceps (supplied by the musculocutaneous nerve) and the coracobrachialis (also supplied by the musculocutaneous nerve) must be retracted medially to access the anterior shoulder joint.
To release them, perform an osteotomy of the tip of the coracoid process (the coracoid must be drilled and tapped before the osteotomy for later screw reattachment).
The axillary artery is surrounded by the cords of the brachial plexus, lying behind the pectoralis minor muscle. Abducting the arm tenses these neurovascular structures, bringing them closer to the coracoid tip and the surgical field. Therefore, the arm should be kept adducted when working near the coracoid.
Retract the coracoid (with its attached muscles) medially. Divide the fascia that fans out from the conjoined tendon (coracobrachialis and short head of biceps) on its lateral side, as the musculocutaneous nerve enters the coracobrachialis on its medial side.
Beneath the conjoined tendon lie the fibers of the subscapularis muscle.
Apply external rotation to the arm to stretch the subscapularis tendon and protect the axillary nerve as it passes below the inferior edge of the muscle.
Insert a blunt instrument between the capsule and the subscapularis. Place traction sutures in the muscle belly to prevent it from retracting medially when cut and to facilitate later reattachment to the humerus. Then, divide the subscapularis from its insertion on the lesser tuberosity.
Finally, incise the capsule (as needed) to enter the joint.

Approach Extensions

Proximal Extension of the Deltopectoral Approach:

To expose the brachial plexus and axillary artery for bleeding control, extend the skin incision superomedially, crossing the middle third of the clavicle.
Subperiosteally dissect the middle third of the clavicle and perform an osteotomy to remove this segment. Divide the subclavius muscle, which runs transversely beneath the clavicle.
Retract the trapezius muscle superiorly and the pectoralis major and minor muscles inferiorly to expose the underlying axillary artery and surrounding brachial plexus.
Take care to avoid damaging the musculocutaneous nerve, the most superficial nerve in the brachial plexus.

Distal Extension of the Deltopectoral Approach:

The deltopectoral approach can be extended into an anterolateral approach to the humerus.
Extend the skin incision along the deltopectoral groove, then curve it distally, following the lateral border of the biceps muscle.
During deep dissection, retract the biceps brachii medially to expose the underlying brachialis muscle. This muscle can then be split along its fibers to access the humerus.

Dangers

The following structures are at risk during the deltopectoral approach:

1. Musculocutaneous Nerve:

The musculocutaneous nerve runs medial to the biceps muscle, 5–8 cm distal to the coracoid process (stay lateral). It can be injured by excessive retraction, causing neurapraxia.

2. Cephalic Vein:

The cephalic vein should be preserved if possible; if injured, it can be ligated.
Preserving it is helpful as an anatomical landmark for revision cases requiring the same approach.

3. Axillary Nerve:

The axillary nerve is at risk when releasing the subscapularis tendon (as it runs distally and medially) or when incising the teres major or latissimus dorsi tendons (as it runs proximally).

4. Anterior Humeral Circumflex Artery:

The anterior humeral circumflex artery runs anteriorly around the proximal humerus, cranial to the pectoralis major tendon.

Closure

Depending on the procedure, the capsule and subscapularis are closed separately or together. Take special care to reattach the subscapularis to the proximal humerus, as detachment can lead to significant iatrogenic problems. The deltopectoral interval is typically not closed; it is simply allowed to fall back into its original position. The cephalic vein should be preserved and protected.