High Yield Overview

ANTERIOR DELTOPECTORAL APPROACH TO THE SHOULDER

Workhorse Approach | Internervous | Extensile | Most Versatile

Critical Deltopectoral Approach Exam Points

True Internervous Plane

Deltoid receives axillary nerve. Pectoralis major receives medial and lateral pectoral nerves. The interval between them is truly internervous - no motor nerves are divided. This is why it is so safe and can be re-entered repeatedly.

Cephalic Vein Landmark

The cephalic vein runs in the deltopectoral groove and is your key landmark. Take it laterally with deltoid (preferred) or medially with pectoralis. Preserving it reduces venous congestion and maintains collateral drainage.

Axillary Nerve at Risk

The axillary nerve descends 5cm below the coracoid tip within the deltoid. Avoid inferior retraction of the deltoid beyond 5cm from coracoid. Use stay sutures on deltoid rather than forceful retraction.

Musculocutaneous Nerve

The musculocutaneous nerve enters coracobrachialis 3-8cm distal to coracoid tip (average 5cm). During deep dissection medial to conjoint tendon, protect this nerve. Avoid aggressive medial retraction of conjoint tendon.

Quick Decision Guide - Approach Applications

Mnemonic

CEPHALICCEPHALIC - The Key Landmark

Memory Hook:The CEPHALIC vein is your roadmap to the shoulder - preserve it and stay safe

Mnemonic

DANGERSDANGERS - Structures at Risk

Memory Hook:Remember the DANGERS to avoid complications during the deltopectoral approach

Mnemonic

SUBSCAPSUBSCAP - Managing the Subscapularis

Memory Hook:The SUBSCAP management determines success of shoulder surgery - get this right

Overview and Indications

The anterior deltopectoral approach is the workhorse approach to the shoulder. First described by von Langenbeck in 1857, it remains the most versatile and widely used approach for shoulder surgery. Its popularity stems from the fact that it is a true internervous plane, provides excellent exposure of anterior and superior shoulder structures, and can be extended proximally and distally for extensive procedures.

Why this approach is preferred:

Internervous plane - no motor nerves divided, muscles retracted not cut
Extensile - can be extended superiorly to clavicle or inferiorly to mid-humerus
Familiar anatomy - consistent landmarks make it safe and reproducible
Reusable - can be re-entered multiple times without additional risk
Low morbidity - minimal functional deficits when performed correctly

Internervous Plane

The deltopectoral approach is a true internervous plane. The deltoid is innervated by the axillary nerve (C5, C6), while pectoralis major is innervated by the medial and lateral pectoral nerves (C5-T1). No motor nerves cross the plane of dissection, making it inherently safe.

Primary indications:

Shoulder arthroplasty - anatomic total shoulder, hemiarthroplasty, reverse total shoulder
Proximal humerus fracture ORIF - anatomic neck, surgical neck, tuberosity fractures
Anterior shoulder instability - open Bankart repair, bone block procedures (Latarjet, Eden-Hybinette)
Rotator cuff pathology - massive tears, irreparable tears requiring superior capsular reconstruction or graft
Tumor and infection - biopsy, resection, debridement
Failed arthroplasty - revision surgery, hardware removal
Fracture nonunion/malunion - proximal humerus, surgical neck

Anatomy and Landmarks

Surface landmarks:

Clavicle (palpable along entire length)
Coracoid process (2-3cm inferior to distal third of clavicle, beneath anterior deltoid)
Acromion process (lateral and posterior shoulder prominence)
Deltopectoral groove (depression between deltoid and pectoralis major)

The deltopectoral interval:

True Internervous Plane

The interval between the deltoid and pectoralis major is one of the few true internervous planes in the body. The deltoid is supplied by the axillary nerve (posterior cord, C5-6), while pectoralis major has dual innervation from medial pectoral (medial cord, C8-T1) and lateral pectoral (lateral cord, C5-7) nerves. No motor nerves cross this plane.

Key anatomical structures:

Vascular anatomy: The cephalic vein is the most visible vessel in this approach. It arises from the dorsal venous arch of the hand, ascends along the radial forearm and anterolateral arm, then enters the deltopectoral groove and pierces the clavipectoral fascia to drain into the axillary vein. Preservation of the cephalic vein reduces postoperative venous congestion and maintains collateral drainage.

Nerve anatomy:

Axillary nerve (C5, C6) - emerges from posterior cord, travels with posterior circumflex humeral artery through quadrangular space, winds around surgical neck of humerus deep to deltoid. Its anterior branch is at risk approximately 5-7cm inferior to the acromion or 5cm below the coracoid tip.
Musculocutaneous nerve (C5, C6, C7) - branch of lateral cord, pierces coracobrachialis muscle 3-8cm (highly variable) distal to coracoid tip, then travels between biceps and brachialis. Can be injured with aggressive medial retraction of conjoint tendon.
Lateral pectoral nerve - from lateral cord, enters deep surface of pectoralis major. Protected as muscle is retracted, not divided.

Internervous Plane

True Internervous Plane

The deltopectoral approach utilizes the interval between the Deltoid (Axillary Nerve, C5-6) and the Pectoralis Major (Medial and Lateral Pectoral Nerves, C5-T1). Because these muscles are supplied by different nerves, the interval can be developed safely without denervating any muscle fibers. This makes it one of the safest and most extensile approaches in the body.

Positioning

Beach Chair Position (Preferred for Arthroplasty)

Advantages:

Easy conversion to open if arthroscopy fails
Familiar anatomy orientation
Easy to assess arm position, tension, and stability intraoperatively
Lower risk of brachial plexus injury compared to lateral
Better access for anesthesia

The beach chair position is preferred by most surgeons for shoulder arthroplasty and open procedures.

Setup:

Beach Chair Setup Steps

Step 1Initial Positioning

Patient supine on standard OR table with beach chair attachment. Back of table elevated 30-45 degrees. Hips and knees flexed for comfort and to prevent sliding.

Step 2Head Positioning

Head secured in padded head holder or ring. Head neutral or slightly tilted to contralateral side. Avoid excessive rotation to prevent cerebral hypoperfusion.

Step 3Operative Arm

Arm free draped and mobile. Place pneumatic arm holder or use assistant/Mayo stand for support during surgery. Arm must be freely mobile for assessment.

Step 4Pressure Points

Pad contralateral shoulder, elbows, sacrum, heels. Check no pressure on peroneal nerve at fibular head if legs positioned laterally.

Cerebral Perfusion

Maintain mean arterial pressure greater than 70mmHg in beach chair position to prevent cerebral hypoperfusion. Risk of watershed infarcts if hypotensive. Communicate with anesthesia if hypotension occurs.

Classification

Approach Variations and Extensions

Standard Deltopectoral Approach Variants

Deltopectoral Approach Variations

Clinical Assessment

Preoperative Clinical Assessment

Patient Factors Affecting Approach

Body habitus: Obesity increases difficulty of exposure
Previous surgery: Scarring, altered anatomy, subscapularis status
Skin condition: Previous incisions, skin quality, radiation
Coagulation status: Anticoagulation management

Physical Examination Relevant to Approach

Palpate coracoid process for incision planning
Assess deltoid muscle bulk and function
Document preoperative nerve function (axillary, musculocutaneous)
Evaluate subscapularis integrity (belly press, lift-off test)

Range of Motion Assessment

Document passive and active ROM in all planes
Assess external rotation (subscapularis flexibility)
Note any contractures affecting positioning

Investigations

Preoperative Imaging

Plain Radiographs

True AP (Grashey): Joint space, humeral head position
Axillary lateral: Glenoid version, subluxation
Scapular Y: Acromion morphology

CT Scan

Glenoid morphology and version assessment
Bone stock for component planning
3D reconstruction for templating
Fracture pattern delineation

MRI

Rotator cuff integrity (especially subscapularis)
Fatty infiltration of cuff muscles
Labral pathology for instability

Management

Approach Selection Considerations

When to Use Deltopectoral Approach

Deltopectoral Approach Indications

Surgical Technique

Incision

Marking:

Identify and mark coracoid process (palpate 2-3cm inferior and medial to anterior acromion)
Mark deltopectoral groove (palpable depression when arm slightly abducted)
Incision starts 1-2cm inferior and lateral to coracoid, extends inferiorly in line with deltopectoral groove

Incision length:

Arthroplasty/extensive reconstruction: 12-15cm
Fracture ORIF: 10-12cm
Limited procedures (instability): 6-8cm

Incision Direction

The incision should be placed in Langer's lines (parallel to relaxed skin tension lines) when possible, but the priority is following the deltopectoral groove. This typically creates an oblique incision from superolateral to inferomedial.

Superficial Dissection

Superficial Exposure Steps

Step 1Skin and Subcutaneous

Incise skin and subcutaneous tissue sharply in line with incision down to superficial fascia. Use cutting diathermy or scalpel. Achieve hemostasis with bipolar cautery.

Step 2Identify Deltopectoral Groove

The deltopectoral groove is immediately apparent as a depression with the cephalic vein running within it. The deltoid is lateral (muscular, bulky), pectoralis major is medial (more tendinous superiorly).

Step 3Manage Cephalic Vein

Identify cephalic vein within deltopectoral fat stripe. Decision: take vein laterally with deltoid (preferred) or medially with pectoralis. Ligate perforating branches but preserve main trunk if possible.

Step 4Develop Interval

Using blunt dissection, develop the interval between deltoid and pectoralis major. This should be avascular and easy to develop. Use finger or gauze to sweep the tissues apart.

Cephalic Vein Preservation

Taking the cephalic vein laterally with the deltoid is preferred. This preserves venous drainage from the arm and reduces postoperative swelling. If the vein is injured, ligate both ends to prevent bleeding and thrombosis.

Complications and Management

Complications of Deltopectoral Approach

Axillary Nerve Anatomy

The axillary nerve exits the quadrangular space posteriorly, wraps around the surgical neck of the humerus, and gives off its anterior branch approximately 5cm below the tip of the coracoid. Placing inferior retractors on the deltoid beyond this distance puts direct traction on the nerve.

Prevention strategies:

Nerve protection: Use anatomic landmarks (5cm rule for axillary nerve, avoid medial retraction for musculocutaneous). Place stay sutures on deltoid and retract with sutures rather than metal retractors.
Subscapularis integrity: Tag before release, mobilize gently, repair anatomically with multiple sutures.
Infection prevention: Standard perioperative antibiotics (cefazolin 2g or vancomycin 15mg/kg), minimize OR time, meticulous hemostasis, layered closure.

Postoperative Care

Postoperative Protocols After Deltopectoral Approach

Immediate Postoperative Care

Sling immobilization with arm at side
Ice and elevation for swelling
Pain management: Multimodal approach (regional block, paracetamol, NSAIDs)
Wound check at 2 weeks

Rehabilitation Phases

Standard Rehabilitation Protocol

Outcomes

Outcomes of Deltopectoral Approach

Approach-Related Outcomes

Deltopectoral Approach Outcomes

Evidence Base and Key Studies

Gerber et al. - Subscapularis Tendon Healing After TSA

Gerber C, Yian EH, Pfirrmann CA, Zumstein MA, Werner CM • J Shoulder Elbow Surg (2011)

Clinical Implication: Subscapularis repair integrity is critical to shoulder function after arthroplasty. Lesser tuberosity osteotomy may improve healing rates but adds technical complexity.

Limitation: MRI follow-up in selected patients; not all patients underwent imaging.

Ball et al. - Axillary Nerve Injury with Deltopectoral Approach

Ball CM, Steger T, Galatz LM, Yamaguchi K • J Shoulder Elbow Surg (2003)

Clinical Implication: The 5cm rule for safe inferior retraction is evidence-based. Use stay sutures to retract deltoid inferiorly rather than rigid retractors.

Limitation: Cadaveric study; anatomy may vary with patient positioning and tissue tension.

Mackenzie - Historical Perspective on Deltopectoral Approach

Mackenzie DB • J Bone Joint Surg Br (1993)

Clinical Implication: The deltopectoral approach has stood the test of time as the workhorse shoulder approach due to its safety profile and versatility.

Elhassan et al. - Pectoralis Major Transfer for Subscapularis Deficiency

Elhassan B, Ozbaydar M, Massimini D, Diller D, Higgins L, Warner JJ • J Bone Joint Surg Am (2008)

Clinical Implication: Pectoralis major transfer is an effective salvage procedure for failed subscapularis after shoulder arthroplasty. Consider early for chronic subscapularis deficiency rather than attempting revision repair.

Limitation: Case series without control group; results dependent on surgical technique and patient selection.

Walch et al. - Subscapularis Repair Techniques and Outcomes

Walch G, Edwards TB, Boulahia A, Boileau P, Mole D, Adeleine P • J Shoulder Elbow Surg (2002)

Clinical Implication: Both subscapularis peel and lesser tuberosity osteotomy are effective. Surgeon preference and case complexity should guide choice. Meticulous repair technique is more important than method.

Limitation: Short follow-up; imaging-based healing may not correlate with clinical outcomes.

Exam Viva Scenarios

Practice these scenarios to excel in your viva examination

VIVA SCENARIOStandard

Scenario 1: Describe the Deltopectoral Approach

EXAMINER

"The examiner asks: 'Describe the anterior deltopectoral approach to the shoulder. What are the key landmarks and structures at risk?'"

EXCEPTIONAL ANSWER

The anterior deltopectoral approach is the workhorse approach for shoulder surgery. It is a true internervous plane between the deltoid, innervated by the axillary nerve, and the pectoralis major, innervated by the medial and lateral pectoral nerves. **Patient positioning:** I would position the patient in beach chair position with the head secured, back elevated 30-45 degrees, and the arm free-draped and mobile. **Surface landmarks:** I identify the coracoid process (2-3cm inferior to the distal clavicle) and the deltopectoral groove (palpable between deltoid and pectoralis). My incision starts 1-2cm inferior and lateral to the coracoid and extends distally in line with the groove for 10-15cm depending on the procedure. **Superficial dissection:** After incising skin and subcutaneous tissue, I identify the **cephalic vein** running in the deltopectoral groove - this is the key landmark. I take the vein laterally with the deltoid (preferred) to preserve venous drainage. I develop the internervous interval between deltoid and pectoralis using blunt dissection. **Deep dissection:** At the superior extent, I ligate the deltoid branch of the thoracoacromial artery to allow deltoid retraction. I incise the clavipectoral fascia lateral to the conjoint tendon (short head biceps and coracobrachialis). This exposes the subscapularis muscle. **Structures at risk:** - **Axillary nerve:** Descends 5cm below coracoid within deltoid - avoid inferior retraction beyond this point - **Musculocutaneous nerve:** Enters coracobrachialis 3-8cm from coracoid tip - protect during medial dissection - **Cephalic vein:** Preserve if possible - **Long head biceps:** Lies in bicipital groove lateral to subscapularis The subscapularis must be managed (split, peel, or osteotomy) to access the glenohumeral joint. After the procedure, anatomic repair of the subscapularis is essential for stability and function.

VIVA SCENARIOChallenging

Scenario 2: Intraoperative Complication - Nerve Injury

EXAMINER

"During a deltopectoral approach for shoulder arthroplasty, you place an inferior retractor on the deltoid. Your registrar tells you they felt a 'pop' and now the deltoid feels softer. What has happened and how do you manage this?"

EXCEPTIONAL ANSWER

This scenario is concerning for **axillary nerve injury** from excessive inferior retraction of the deltoid. The 'pop' sensation and change in deltoid tone suggest nerve disruption or traction injury. **Immediate intraoperative management:** First, I would immediately **remove the retractor** and assess the situation. The axillary nerve descends within the deltoid approximately 5cm below the coracoid tip. If an inferior retractor was placed beyond this distance, or with excessive force, the nerve can be stretched or injured. **Assessment:** - I would palpate the axillary nerve location (5cm below coracoid, wrapping around surgical neck) - Visually inspect if nerve is visible at inferior wound margin - Assess if deltoid tone is truly lost or if this is artifact from positioning - Consider whether I need to extend approach inferiorly to directly visualize nerve **Decision points:** If I can visualize the nerve and it appears in continuity with no transection, I would proceed with the case using **alternative retraction methods**: - Use stay sutures on deltoid rather than rigid retractors - Place retractors within the safe zone (less than 5cm from coracoid) - Consider assistant hand-held retraction If the nerve appears transected (rare), I would: - Complete the primary procedure efficiently - Directly repair the nerve with microsurgical technique or mark with clip for later repair - Consider nerve conduit or nerve transfer if indicated - Document extensively in operative note **Postoperative management:** - Document nerve injury clearly in operative note - Inform patient and family immediately about complication - Arrange early EMG/NCS (3-6 weeks if no clinical recovery) - Monitor for deltoid function recovery (most neurapraxias recover in 3-6 months) - Physiotherapy to maintain shoulder ROM and prevent stiffness - If no recovery by 6 months, consider nerve exploration, nerve grafting, or tendon transfers (trapezius transfer for abduction) **Prevention:** This situation reinforces the importance of the **5cm rule** and using stay sutures rather than rigid retractors for inferior deltoid retraction.

VIVA SCENARIOCritical

Scenario 3: Failed Subscapularis Repair After Arthroplasty

EXAMINER

"A patient returns 6 months after total shoulder arthroplasty via deltopectoral approach with loss of active internal rotation and anterior instability. MRI confirms complete subscapularis rupture. How do you manage this?"

EXCEPTIONAL ANSWER

This is a challenging scenario - failed subscapularis repair after shoulder arthroplasty is a serious complication that significantly impacts function. Subscapularis deficiency leads to **loss of internal rotation**, **anterior instability**, and **poor patient satisfaction**. **Assessment:** First, I would confirm the diagnosis: - Clinical exam: Loss of active internal rotation, positive belly-press test, positive lift-off test (if passive IR possible), anterior apprehension - MRI confirmation of complete subscapularis rupture - X-rays to assess prosthesis position, ensure no loosening or malposition contributing to instability - CT scan if concerned about glenoid component positioning (version) **Contributing factors to consider:** - Was the initial repair inadequate? (Insufficient sutures, poor tissue quality, wrong tensioning) - Is there component malposition? (Excessive retroversion of humeral component can tension subscapularis excessively; excessive anteversion of glenoid can contribute to anterior instability) - Is there poor tissue quality? (Revision case, fatty infiltration, chronic tear) - Is there biological healing failure? (Smoking, diabetes, steroids) **Management options:** *Option 1: Subscapularis Revision Repair* (if tissue quality adequate and failure is acute - less than 6 months) - Re-explore via deltopectoral approach - Mobilize subscapularis edges - Assess for adequate mobilization to reach lesser tuberosity - Repair to bone using transosseous sutures or suture anchors - Consider augmentation with biologic graft if tissue poor quality - Post-op: protect in sling in neutral rotation for 6 weeks, then gradual ROM *Option 2: Pectoralis Major Transfer* (preferred if chronic, tissue poor, inadequate subscapularis tissue) - Transfer pectoralis major to lesser tuberosity to act as anterior stabilizer and internal rotator - Surgical technique: harvest pectoralis major tendon near insertion, pass deep to conjoint tendon, attach to lesser tuberosity or subscapularis remnant - This has become the gold standard for irreparable subscapularis after arthroplasty - Better results than revision repair in chronic cases - Post-op: protect for 6 weeks then gradual strengthening *Option 3: Component Revision* (if malposition contributing) - If humeral or glenoid component malpositioned, consider component revision to address biomechanical issue - Combined with subscapularis repair or pectoralis transfer *Option 4: Conversion to Reverse Shoulder Arthroplasty* (if elderly, low demand, combined cuff deficiency) - If patient is older with low demands and subscapularis is irreparable - Reverse arthroplasty is less dependent on subscapularis function - Treats both instability and functional deficit **My approach for this patient:** Given this is 6 months post-op with complete rupture, I would favor **pectoralis major transfer** as the tissue quality is likely poor and chronic changes have occurred. I would: 1. Confirm no component malposition on CT 2. Counsel patient about realistic expectations (improve stability and internal rotation, but unlikely to achieve normal strength) 3. Perform pectoralis major transfer to lesser tuberosity 4. Protected rehabilitation for 6 weeks then gradual strengthening 5. Close follow-up to ensure healing **Prevention:** This case emphasizes the critical importance of: - Anatomic subscapularis repair with multiple heavy sutures at initial surgery - Adequate mobilization of subscapularis without excessive tension - Preserving tissue quality during approach - Patient compliance with postoperative restrictions

MCQ Practice Points

Internervous Plane

Q: The deltopectoral approach is a true internervous plane between which two muscles and their respective nerve supplies? A: Deltoid (axillary nerve, C5-6) and pectoralis major (medial and lateral pectoral nerves, C5-T1). No motor nerves are divided in this approach, making it safe and repeatable.

Key Landmark

Q: What is the key superficial landmark for the deltopectoral approach and what is the preferred management? A: The cephalic vein running in the deltopectoral groove. Preferred management is to take it laterally with the deltoid to preserve venous drainage from the upper limb and reduce postoperative swelling.

Axillary Nerve Safety

Q: How far below the coracoid tip does the anterior branch of the axillary nerve descend, and what is the clinical implication? A: The axillary nerve descends approximately 5cm below the coracoid tip within the deltoid muscle. Inferior retraction of the deltoid beyond this distance risks axillary nerve traction injury. Use stay sutures rather than rigid retractors.

Musculocutaneous Nerve

Q: Where does the musculocutaneous nerve pierce the coracobrachialis muscle and why is this clinically important? A: The musculocutaneous nerve pierces coracobrachialis 3-8cm distal to the coracoid tip (average 5cm, but highly variable). Aggressive medial retraction of the conjoint tendon during deep dissection can injure this nerve, causing loss of biceps and brachialis function and sensory loss over lateral forearm.

Subscapularis Management

Q: What are the three main techniques for managing the subscapularis in the deltopectoral approach and when is each used? A: 1. Subscapularis peel - peeling tendon off lesser tuberosity (arthroplasty, extensive exposure). 2. Lesser tuberosity osteotomy - bone-tendon unit preserved (revision arthroplasty, poor tendon quality). 3. Subscapularis split - horizontal split at junction upper 2/3 and lower 1/3 (instability procedures, limited exposure). Peel and osteotomy are for arthroplasty; split is for instability.

Subscapularis Repair

Q: Why is subscapularis repair critical after deltopectoral approach and what happens if it fails? A: Subscapularis is the primary anterior stabilizer and internal rotator of the shoulder. Failure to repair leads to anterior instability, loss of active internal rotation, and poor functional outcomes. The subscapularis must be repaired anatomically to the lesser tuberosity with multiple heavy sutures.

Australian Context

Epidemiology: The deltopectoral approach is the standard approach for shoulder arthroplasty in Australia. According to the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), shoulder arthroplasty rates have increased significantly over the past decade, with over 5,000 primary shoulder replacements performed annually.

Practice patterns:

Beach chair positioning is most common in Australian practice
Subscapularis peel is preferred by most surgeons for arthroplasty
Lesser tuberosity osteotomy gaining popularity for revision cases
Standard perioperative antibiotic prophylaxis: cefazolin 2g (vancomycin if penicillin allergic)

Medicolegal considerations:

Obtain informed consent discussing nerve injury risk (axillary, musculocutaneous)
Document subscapularis repair technique and quality
Discuss risk of subscapularis failure and its consequences
Early postoperative assessment of nerve function with documentation

Training: The deltopectoral approach is a core skill for orthopaedic trainees in Australia. Competence is expected for Orthopaedic examination and is a requirement for independent practice in shoulder surgery.