Deltopectoral Approach to Shoulder

Why This Approach Matters

The deltopectoral approach is the gold standard anterior shoulder approach - the first approach most orthopaedic surgeons learn and the last they use in practice. It's the internervous plane workhorse for 95% of shoulder arthroplasties, 80% of proximal humerus fractures, and virtually all anterior shoulder stabilization procedures requiring open surgery.

Three reasons this approach dominates shoulder surgery:

1. True Internervous Plane (Muscle Level): Deltoid (axillary nerve C5-C6) vs pectoralis major (medial/lateral pectoral nerves C5-T1) - no motor denervation
2. Extensile Without Consequences: Can extend from sternoclavicular joint to mid-humerus without crossing new nerve territories
3. Subscapularis Preservation: Direct visualization allows anatomic subscapularis repair - critical for postoperative stability and function

The Historical Context:

• 1920s: Codman describes "through the shoulder" approach for fractures
• 1950s: Neer popularizes deltopectoral for arthroplasty and fracture work
• 2004: Reverse shoulder arthroplasty explosion (Grammont) - deltopectoral becomes most common shoulder approach worldwide
• 2020s: Subscapularis management debate continues (tenotomy vs osteotomy vs peel - no winner per meta-analyses)

Global Practice and Registry Trends: Shoulder arthroplasty volume has risen sharply worldwide, driven almost entirely by reverse total shoulder arthroplasty (RTSA). Major joint registries (AOANJRR, NJR England/Wales, AJRR, Nordic registries) consistently report that reverse TSA now substantially outnumbers anatomic TSA, reflecting expanded indications (cuff tear arthropathy, irreparable cuff tears, complex proximal humerus fractures). The deltopectoral approach is the dominant exposure for all of these in every registry. The approach's learning curve is short, but mastery requires understanding subscapularis biomechanics and rotator interval anatomy - two areas where fellowship training significantly impacts outcomes.

Primary Indications

1. Shoulder Arthroplasty (Most Common)

• Anatomic Total Shoulder Arthroplasty: Glenohumeral arthritis with intact rotator cuff
• Reverse Total Shoulder Arthroplasty: Cuff tear arthropathy, massive irreparable cuff tears, proximal humerus fracture sequelae
• Hemiarthroplasty: Proximal humerus fractures (4-part, head-split), avascular necrosis (young patients), glenoid bone loss
• Revision Arthroplasty: Component loosening, instability, infection (staged)

2. Proximal Humerus Fractures

• 3-part fractures: Displaced greater tuberosity + surgical neck (deltoid origin intact)
• 4-part fractures: All tuberosities + head fragment displaced (AVN risk 20-75%)
• Head-split fractures: Articular surface fracture (ORIF vs hemiarthroplasty decision)
• Fracture-dislocation: Anterior dislocation with displaced fracture

3. Anterior Shoulder Instability

• Latarjet Procedure: Recurrent anterior instability with significant glenoid bone loss (>20%)
• Open Bankart Repair: Failed arthroscopic stabilization, revision cases
• Capsulorrhaphy: Multidirectional instability (inferior component)

4. Other Pathology

• Subscapularis Repair: Isolated subscapularis rupture (traumatic or degenerative)
• Biceps Tenodesis: Long head biceps pathology (SLAP tears age >40, biceps instability)
• Tumor Resection: Proximal humerus primary tumors (osteosarcoma, chondrosarcoma), metastatic disease
• Infection Debridement: Glenohumeral septic arthritis, hardware infection (staged arthroplasty)

Relative Contraindications

Absolute:

• Active Infection: Unless debridement is the goal (staged arthroplasty protocol)
• Inadequate Soft Tissue Envelope: Massive trauma with tissue loss (consider latissimus dorsi flap)

Relative:

• Axillary Nerve Palsy: Pre-existing deficit (careful - may worsen with retraction, document preop)
• Brachial Plexus Injury: Obstetric palsy (medial retraction on plexus is higher risk)
• Previous Surgery: Infection risk higher, tissue planes scarred (doable but slower)
• Posterior Pathology: Posterior glenoid bone loss, posterior instability (wrong approach - use posterior)
• Morbid Obesity: Body habitus makes exposure difficult (positioning critical)

Clinical Assessment

History Red Flags:

• Previous Surgery: Infection risk 3× higher with prior incisions (Klika et al, CORR 2014)
• Neurological Symptoms: Axillary nerve palsy (30% with anterior dislocation), brachial plexopathy
• Medical Comorbidities: Diabetes (infection risk), anticoagulation (haematoma risk), smoking (non-union risk)

Physical Examination Essentials:

• Axillary Nerve Function: Deltoid contraction, sensation over lateral deltoid (document preop)
• Rotator Cuff Assessment: Subscapularis function (belly press, bear hug, lift-off tests), external rotation lag (infraspinatus)
• Range of Motion: Forward elevation, external rotation (passive vs active - cuff integrity)
• Instability Testing: Anterior apprehension, relocation test, load-and-shift

Neurovascular Examination (MANDATORY Documentation):

• Axillary nerve: Deltoid power (MRC 0-5), sensation lateral arm
• Radial nerve: Wrist/finger extension, first web space sensation
• Median nerve: Thumb opposition, index finger sensation
• Ulnar nerve: Finger abduction, small finger sensation
• Vascular: Radial pulse, capillary refill, limb perfusion

Imaging Essentials

Radiographs (MANDATORY):

• AP Shoulder (True AP): Patient rotated 30-40° (scapular plane perpendicular to cassette)
• Scapular Y Lateral: Head position relative to glenoid (dislocation, fracture pattern)
• Axillary Lateral: Glenoid bone loss, humeral head position (if patient can abduct arm)
• Velpeau Axillary: Modified axillary if patient cannot abduct (fracture cases)

CT Scan (Fractures, Bone Loss):

• 3D Reconstruction: Fracture pattern, fragment displacement, tuberosity comminution
• Glenoid Bone Loss: En-face glenoid view (bone loss % - Latarjet indication if >20%)
• Humeral Head Impaction: Hill-Sachs measurement (engaging vs non-engaging)

MRI (Soft Tissue Pathology):

• Rotator Cuff Integrity: Subscapularis (lesser tuberosity insertion), supraspinatus, infraspinatus
• Labral Pathology: Bankart lesion (anterior labrum), SLAP tears (biceps anchor)
• Muscle Quality: Fatty infiltration (Goutallier grade - predicts repair healing)

Surgical Planning Decision Points

Subscapularis Management (The Exam Debate):

The Evidence: According to PubMed, the best current syntheses are a systematic review (Choate et al, JSES 2017/2018) and a network meta-analysis (Ahmed et al, Shoulder & Elbow 2022). Both show broadly equivalent clinical outcomes (Constant, ASES, range of motion, strength) across tenotomy, lesser tuberosity osteotomy and peel - but with a consistent signal that osteotomy and peel achieve higher tendon healing / bony union rates (LTO union ~93%, peel ~84-87%, tenotomy healing ~75-80%). Choose based on surgeon experience, bone quality and patient factors.

Essential Instrumentation

Standard Orthopaedic Set:

• Scalpel (10 blade for skin, 15 blade for subscapularis)
• Self-retaining retractor (Kolbel shoulder retractor, Fukuda ring retractor)
• Hohmann retractors (blunt - protect axillary nerve)
• Army-Navy retractors (superficial tissue)
• Electrocautery (cutting and coagulation)

Shoulder-Specific Instruments:

• Humeral Head Retractors: Fukuda humeral retractor, Darrach retractor (elevate head)
• Coracoid Retractor: Blunt Hohmann around coracoid (protect conjoined tendon)
• Subscapularis Retractor: Narrow Hohmann (elevate subscapularis off anterior capsule)
• Glenoid Retractors: Anterior/posterior glenoid retractors (expose glenoid face)

Fracture-Specific (If ORIF):

• Heavy non-absorbable suture (#2 Ethibond, FiberWire) for tuberosity repair
• Suture anchors (5.5mm for greater tuberosity, 3.5mm for lesser tuberosity)
• Locking plates (PHILOS, proximal humerus specific)
• Cerclage suture/cable (shaft extension fixation)

Arthroplasty-Specific (If TSA/Reverse):

• Shoulder arthroplasty set (manufacturer-specific trial implants)
• Glenoid preparation (reamers, drills, impactors for baseplate/glenoid component)
• Humeral preparation (reamers, broaches, stem inserters)
• Cement (if cemented humeral stem)

Implant Considerations

Fracture Fixation:

• Proximal Humerus Locking Plate: 3-4 part fractures in younger patients (<65 years) with good bone
• Suture Anchors: Tuberosity fixation to shaft (0.5cm lateral to bicipital groove for GT)
• Heavy Suture: #5 non-absorbable (tuberosity-to-tuberosity, tuberosity-to-shaft)

Arthroplasty:

• Reverse TSA: Now the majority of shoulder arthroplasties in most registries (AOANJRR, NJR, AJRR) - cuff tear arthropathy, massive irreparable cuff tears, complex fractures
• Anatomic TSA: Intact rotator cuff, primary glenohumeral osteoarthritis (younger, cuff-intact patients)
• Hemiarthroplasty: Declining use - reserved for fracture sequelae in younger patients or inadequate glenoid bone stock

Surgical Team Setup

Personnel:

• Surgeon (1st operator)
• Assistant (1st assistant - critical for retraction and humeral head delivery)
• Scrub nurse (shoulder case experience - implant familiarity)
• Anaesthetist (regional block + GA preferred)

Positioning Team:

• 2-3 people for lateral positioning
• Bean bag and kidney rests available
• Arm holder (McConnell arm positioner) vs table-mounted arm support

Beach Chair Position (Most Common)

Setup:

1. Operating Table: Standard OR table, head of bed elevated 30-40° (semi-recumbent)
2. Patient Position: Supine, torso rotated 20-30° toward operative side (opens deltopectoral interval)
3. Head Support: Horseshoe headrest or gel headring (neck neutral, avoid rotation)
4. Arm Position: Arm free drape allows full range of motion (adduction to extension to abduction)

Advantages:

• Anatomic Orientation: Surgeon works in familiar position (like outpatient clinic exam)
• Easier Conversion to Extensile: Can extend to clavicle or distally without repositioning
• Airway Access: Anaesthetist has full access (beach chair hypotension manageable)
• Better for Teaching: Assistant and surgeon have symmetrical view

Disadvantages:

• Hypotension Risk: Beach chair position reduces cerebral perfusion (maintain MAP >70 mmHg)
• Venous Air Embolism: Rare but catastrophic (0.1-1% - subclavian vein injury with air entrainment)

Beach Chair Positioning Protocol:

1. Supine on OR table, operative side 10cm from table edge
2. Elevate head of bed 30-40° (thoracic hinge just caudal to scapula)
3. Flex knees 30° (relaxes sciatic nerve, prevents patient sliding)
4. Arm support (McConnell or table-mounted) - shoulder free to 0° extension
5. Pad all pressure points (heels, sacrum, elbows)
6. Secure torso with tape (prevents sliding if table tilted)

Lateral Decubitus Position (Alternative)

Setup:

1. Patient Position: Lateral decubitus, operative side up, non-operative side on beanbag
2. Stabilization: Beanbag molded to torso, kidney rests for pelvis (prevent rolling)
3. Arm Position: Arm suspended from overhead boom (Watson shoulder positioner) - 30° flexion, 30° abduction
4. Head Position: Padded headrest, neck neutral

Advantages:

• No Hypotension: Maintains normal cerebral perfusion
• Gravity Assistance: Arm suspended - humeral head drops away from glenoid (easier glenoid exposure)
• Consistent Positioning: Arm fixed in space (vs beach chair where arm position varies)

Disadvantages:

• Disorientation: Surgeon works from unusual position (learning curve)
• Limited Extension: Difficult to extend incision medially (clavicle obscured)
• Setup Time: 10 minutes longer for positioning (beanbag, arm boom)

Interscalene Block Considerations

Why Interscalene?

• Blocks brachial plexus at nerve roots (C5-C6-C7) - deltopectoral exposure innervation
• Superior early postoperative pain control versus systemic opioids alone
• Reduces perioperative opioid consumption and improves recovery (standard of care for shoulder arthroplasty in most centres)

Diaphragm Paralysis:

• 100% of interscalene blocks cause ipsilateral hemidiaphragm paralysis (phrenic nerve C3-C4-C5)
• Relative contraindication: Severe COPD (FEV1 <40%), contralateral phrenic palsy
• Consider liposomal bupivacaine (Exparel) field infiltration if block contraindicated

Surface Landmarks (Mark Preoperatively)

Bony Landmarks:

1. Coracoid Process: 2cm inferior and medial to clavicle (palpable in delto-pectoral groove)
2. Acromion: Lateral edge - measure 5cm distally (axillary nerve position)
3. Clavicle: Medial extent of incision if extending proximally
4. Deltoid Insertion: 10cm distal to acromion on humeral shaft (V-shaped)

Soft Tissue Landmarks:

1. Deltopectoral Groove: Palpable fat stripe between deltoid (lateral) and pectoralis major (medial)
2. Cephalic Vein: Runs IN the deltopectoral groove (classically retracted laterally with the deltoid)

Internervous Plane Anatomy

The TRUE Internervous Plane:

• Deltoid (lateral): Axillary nerve (C5-C6) from posterior cord
• Pectoralis Major (medial): Medial and lateral pectoral nerves (C5-C6-C7-T1)
• Plane: Deltopectoral groove (fat stripe containing cephalic vein)

The MYTH of Clavipectoral Fascia: The approach divides the clavipectoral fascia (lateral to conjoined tendon) which contains branches of the lateral pectoral nerve to pectoralis minor. This is NOT an internervous plane - you're dividing nerve branches. However, denervating pectoralis minor has no functional consequence (pec major remains innervated).

Critical Neurovascular Anatomy

Axillary Nerve:

• Course: Exits quadrangular space with posterior circumflex humeral artery (PCHA)
• Position: 5-7cm inferior to acromion on deep surface of deltoid (at teres major insertion level)
• Branches: Anterior branch (deltoid), posterior branch (deltoid + teres minor), sensory (lateral cutaneous nerve of arm)
• At Risk: Inferior dissection beyond teres major insertion, anterior humeral circumflex artery ligation (shared blood supply)

Musculocutaneous Nerve:

• Course: Branch of lateral cord, enters coracobrachialis 3-8cm below coracoid tip
• Position: On medial arm (deep to short head biceps and coracobrachialis)
• At Risk: Aggressive medial retraction (brachial plexus stretch), coracoid osteotomy (Latarjet procedure)
• Protection: Gentle medial retraction, release conjoined tendon from coracoid if tight

Cephalic Vein:

• Course: Runs IN the deltopectoral groove (superficial to clavipectoral fascia)
• Retraction: Classically retracted laterally with the deltoid (most tributaries are deltoid-side, so fewer vessels need dividing); either direction is acceptable if justified on tributary anatomy
• Branches: Multiple tributary veins to deltoid and pec major (ligate or cauterise individually)
• Injury Risk: Avulsion if mobilised aggressively - a recognised cause of deltopectoral haematoma

Anterior Circumflex Humeral Artery (ACHA):

• Course: Branch of axillary artery, runs transversely across anterior humerus (deep to coracobrachialis)
• Position: Just inferior to coracoid tip (3-5cm below), crosses subscapularis at musculotendinous junction
• At Risk: Subscapularis release, inferior capsular release
• Ligation: Safe to ligate (collateral flow via PCHA) but control precisely (haematoma risk)

Rotator Interval Anatomy

The Rotator Interval: Triangular space bounded by:

• Superior: Supraspinatus tendon (footprint on greater tuberosity)
• Inferior: Subscapularis tendon (footprint on lesser tuberosity)
• Base: Coracoid process
• Contents: Long head biceps tendon, coracohumeral ligament, superior glenohumeral ligament

Long Head Biceps Tendon (LHB):

• Intra-articular Course: Origin at supraglenoid tubercle (biceps anchor/SLAP region)
• Exit Point: Bicipital groove (between greater and lesser tuberosities)
• Landmark: LHB tendon marks anterior border of greater tuberosity - rotator cuff reference

Why LHB Matters: The bicipital groove separates greater tuberosity (supraspinatus, infraspinatus, teres minor insertions) from lesser tuberosity (subscapularis insertion). In fractures, the groove helps identify fracture fragments. In arthroplasty, it's the reference for humeral version (30° retroversion from bicipital groove).

Subscapularis Anatomy

Muscle Anatomy:

• Origin: Subscapular fossa (anterior scapula)
• Insertion: Lesser tuberosity (5 distinct tendinous bands - "comma" sign on MRI)
• Innervation: Upper and lower subscapular nerves (C5-C6) from posterior cord

Critical Surgical Relationships:

1. Musculotendinous Junction: 3-4cm medial to lesser tuberosity - thin tendinous area (weak point)
2. Capsule Fusion: Subscapularis tendon fuses with anterior capsule (must release together)
3. Axillary Nerve: Crosses inferior border of subscapularis (teres major level - stay superior)
4. Anterior Circumflex Artery: Crosses subscapularis at musculotendinous junction (control if divided)

Subscapularis Preservation Principles:

• Tag Stitch: Place tag suture 1cm from lesser tuberosity insertion BEFORE release (preserves tissue quality)
• Preserve Insertion: Lesser tuberosity osteotomy preserves bone-tendon interface (strongest repair)
• Repair Tension: Subscapularis repair with arm in neutral rotation (avoid overtightening - limits external rotation)

Step 1: Skin Incision and Superficial Dissection

Incision Planning:

• Start Point: Coracoid tip (2cm inferior to clavicle, 2cm medial to acromion - palpate)
• Direction: Extend distally toward deltoid insertion (V-shaped) - follows deltopectoral groove
• Length: 10-12cm for arthroplasty, 12-15cm for fractures (extensile exposure)
• End Point: Stop 5cm above deltoid insertion (preserves axillary nerve safety margin)

Marking the Incision: Mark with sterile marker:

1. Coracoid tip (palpate through skin - firm bony landmark)
2. Line extending toward deltoid insertion (lateral to axilla - avoid scar contracture)
3. Approximate deltopectoral groove position (medial third of shoulder contour)

Skin Incision:

• 10 blade scalpel, sharp dissection through dermis
• Subcutaneous tissue to clavipectoral fascia (3-5mm depth)
• Achieve haemostasis with electrocautery (skin edge bleeding)

Identify Cephalic Vein: The cephalic vein runs IN the deltopectoral groove (within the fat stripe between the muscles). Look for:

• Blue vessel within the superficial fat stripe
• Fat stripe between deltoid (lateral) and pectoralis major (medial)
• Tributary branches to both muscles (multiple small veins)

Step 2: Deep Dissection - Develop Deltopectoral Interval

Mobilize Cephalic Vein:

1. Identify the vein in the deltopectoral fat stripe
2. Ligate or cauterise tributary branches with 3-0 ties or bipolar cautery
3. Retract the vein laterally with the deltoid (gentle - avoid avulsion)
4. If the vein avulses: stay calm, apply direct pressure, ligate both ends, proceed (no functional consequence)

Deltoid Retraction:

• Self-retaining retractor (Kolbel shoulder retractor) retracts the deltoid laterally
• Place a Hohmann retractor on the lateral humerus (blunt tip - protects the axillary nerve)
• Keep inferior retraction/dissection out of the axillary nerve zone (the nerve crosses ~5cm below the greater tuberosity)

Pectoralis Major Retraction:

• Handheld Army-Navy retractor retracts pec major medially
• Gentle medial retraction (avoid brachial plexus stretch)
• Release superior 2cm of pec major insertion from humerus if tight (improves exposure)

Step 3: Clavipectoral Fascia Division

Identify Clavipectoral Fascia:

• Thin white fascial layer deep to cephalic vein
• Extends from coracoid process (lateral border) to clavicle (superior border)
• Lateral pectoral nerve visible in fascia (tiny nerve branches - will divide)

Divide Fascia:

1. Identify Coracoid Process: Palpate through fascia (bony landmark)
2. Incise Fascia LATERAL to Conjoined Tendon: Start 0.5cm lateral to coracoid tip
3. Extend Superior and Inferior: Superior to clavicle (if needed), inferior 5-8cm (to deltoid insertion level)
4. Preserve Conjoined Tendon: Short head biceps + coracobrachialis (do NOT divide)

What You See After Fascial Division:

• Laterally: Deltoid muscle (red muscle belly)
• Medially: Conjoined tendon (short head biceps + coracobrachialis - white tendinous structure from coracoid)
• Deep: Subscapularis muscle (anterior shoulder muscle - covers anterior capsule)

Step 4: Identify and Protect Musculocutaneous Nerve

Why This Matters: The musculocutaneous nerve enters coracobrachialis 3-8cm below coracoid tip (variable). Aggressive medial retraction can stretch the entire brachial plexus OR directly injure the nerve if it enters proximally.

Nerve Identification (Optional but Recommended):

1. Palpate conjoined tendon medially
2. Musculocutaneous nerve enters muscle belly 3-8cm below coracoid (you may see or palpate - firm white structure)
3. If nerve enters proximally (<3cm): Place tag suture on coracoid, release conjoined tendon from coracoid tip (improves mobilization, protects nerve)

Protection Strategy:

• Gentle medial retraction only (do NOT reef on conjoined tendon)
• If exposure tight: Release superior 2cm of conjoined tendon from coracoid (Gerber technique)
• Never use sharp Hohmann retractors medially (blunt only)

Step 5: Expose Subscapularis and Rotator Interval

Rotate Arm to Expose Subscapularis:

• External Rotation: Brings subscapularis anterior (easier to see insertion on lesser tuberosity)
• Arm Position: 20-30° external rotation (hand rests on patient's abdomen if beach chair)

Identify Long Head Biceps Tendon:

1. Divide biceps sheath longitudinally (thin fascia overlying bicipital groove)
2. Identify LHB tendon in groove (white cord - reference landmark)
3. Assess tendon quality (if degenerative: tenotomy or tenodesis)

Biceps Management Decision:

Tenotomy (release at origin - let retract):

• Advantages: Fast (30 seconds), low complication rate
• Disadvantages: Popeye deformity (30%), cramping (10%)
• Indication: Age >65, sedentary, arthroplasty cases

Tenodesis (fix to humerus):

• Advantages: No Popeye, better cosmesis
• Disadvantages: Adds 10 minutes, tenodesis failure 5%
• Indication: Age <65, active, cosmesis important

Identify Subscapularis Insertion:

• Lesser tuberosity is medial to bicipital groove (LHB is the landmark)
• Subscapularis tendon inserts on lesser tuberosity (5 distinct bands visible)
• Musculotendinous junction 3-4cm medial to insertion (thin area)

Step 6: Subscapularis Management (CRITICAL STEP)

Option A: Subscapularis Tenotomy (Most Common)

1. Tag Stitch: Place heavy non-absorbable suture (#2 Ethibond) 1cm from lesser tuberosity insertion

   • Why 1cm? Preserves tissue quality for repair (avoid tendinous edge fraying)
   • Use locking Krackow stitch or mattress suture (strong hold)

2. Release Subscapularis: Electrocautery or sharp dissection 1cm from lesser tuberosity

   • Release superior border (rotator interval - coracohumeral ligament)
   • Release inferior border (axillary nerve 1-2cm below - stay superior)
   • Release anterior capsule WITH subscapularis (fused structures)

3. Mobilize Tendon: Blunt dissection between subscapularis and anterior glenoid

   • Release adhesions medially (allows later repair without tension)
   • Preserve upper and lower subscapular nerve branches (enter muscle belly medially)

Option B: Lesser Tuberosity Osteotomy

1. Mark Osteotomy: 0.5cm medial to lesser tuberosity (5mm bone wafer with tendon insertion)
2. Osteotomy Cut: Oscillating saw or osteotome (5mm depth, preserves tendon insertion)
3. Elevate Fragment: Wafer of bone with subscapularis insertion attached (bone-tendon unit)
4. Protect Fragment: Place in lap sponge (keep moist - will repair at closure)

The Exam Question: "Which is better - tenotomy or osteotomy?"

Answer: The current evidence (Choate et al systematic review, JSES 2017/2018; Ahmed et al network meta-analysis, Shoulder & Elbow 2022) shows broadly equivalent clinical outcomes between tenotomy, lesser tuberosity osteotomy and peel - similar Constant/ASES scores, range of motion and strength. The consistent difference is structural healing: osteotomy achieves the highest union (~93%) and peel intermediate healing (~84-87%), versus tenotomy tendon healing (~75-80%). Importantly, healing on imaging correlates poorly with clinical function.

Conclusion: Choose based on surgeon comfort, bone quality and patient factors. Many surgeons favour tenotomy for speed and simplicity; those prioritising structural healing (e.g. younger patients, good bone) may prefer osteotomy or peel. The repair technique and tension matter more than the takedown method.

Step 7: Capsular Release and Humeral Head Exposure

Anterior Capsule Release:

1. Subscapularis released (tendon reflected medially with tag sutures)
2. Anterior capsule visible (thin white membrane covering humeral head)
3. Incise capsule longitudinally (parallel to LHB tendon)
4. Extend capsulotomy: Superior to rotator interval, inferior to 6 o'clock (axillary nerve below)

Release Rotator Interval:

• Interval between subscapularis (inferior) and supraspinatus (superior)
• Contains coracohumeral ligament (thickest portion of capsule)
• Divide interval sharply (releases superior capsule - improves external rotation)

Inferior Capsular Release (If Needed for Mobilization):

• Place blunt Hohmann retractor inferior to humeral head
• Elevator or cautery releases inferior capsule from anatomic neck
• WATCH: Axillary nerve 1-2cm below (stays on deep deltoid - protected by Hohmann)
• WATCH: Anterior circumflex humeral artery crosses here (control if bleeding)

Humeral Head Delivery:

1. Arm Position: Extension 20-30° (brings head anterior), external rotation 30° (rotates head into wound)
2. Retractor Placement: Fukuda humeral head retractor or Darrach retractor posterior to head (elevates into wound)
3. Confirm Delivery: Entire anatomic neck visible 360° (for arthroplasty), fracture fragments visible (for ORIF)

Step 8: Glenoid Exposure (If Arthroplasty)

Arm Position for Glenoid View:

• Extension: 45° (maximal)
• External Rotation: 30-45°
• Abduction: 0-20° (opens joint space)

Glenoid Retractor Placement:

1. Anterior Retractor: Hohmann on anterior glenoid rim (retracts humeral head posteriorly)
2. Posterior Retractor: Hohmann on posterior glenoid rim (stabilizes scapula)
3. Inferior Retractor: Blunt Hohmann inferior (protects axillary nerve, improves inferior exposure)

Labral Excision:

• Rongeur or cautery removes glenoid labrum circumferentially (exposes subchondral bone)
• Preserve bone (do NOT rongeur into glenoid surface - need bone stock for component)

Glenoid Preparation:

• Ream to subchondral bone (manufacturer-specific technique)
• Anatomic TSA: Glenoid component cemented (40mm diameter polyethylene)
• Reverse TSA: Baseplate screwed to glenoid (36mm metal baseplate + glenosphere)

Step 9: Proximal Humerus Management

For Arthroplasty:

1. Humeral Head Cut: Oscillating saw at anatomic neck (20-30° retroversion from bicipital groove)
2. Canal Preparation: Reamers and broaches (proximal humerus canal opened for stem)
3. Trial Reduction: Trial stem + trial head (check stability, ROM, soft tissue tension)
4. Final Implant: Cemented or press-fit stem, modular head (restore anatomy)

For Fracture ORIF:

1. Reduce Fracture: Provisional K-wires hold tuberosities to shaft
2. Definitive Fixation:
   • Locking plate (PHILOS pattern - 3.5mm locking screws in head)
   • Suture anchors (tuberosity to shaft - 0.5cm lateral to groove for GT)
   • Heavy suture (#5 FiberWire - tuberosity-to-tuberosity, figure-of-8 pattern)
3. Check Fixation: Fluoroscopy (AP, axillary, scapular Y - confirm reduction, hardware position)

Step 10: Closure and Subscapularis Repair

Subscapularis Repair (MOST CRITICAL STEP):

For Tenotomy:

1. Arm Position: Neutral rotation (avoid overtightening - limits ER postop)
2. Repair Technique: Tag sutures passed through drill holes in lesser tuberosity
   • 3-4 drill holes (3.2mm) at bone-tendon interface (lesser tuberosity)
   • Pass tag sutures through holes, tie over bone bridge
   • Alternative: Suture anchors (5.5mm) in lesser tuberosity, mattress sutures to tendon
3. Repair Quality Check: Subscapularis should cover <50% of humeral head component (if >50%, too tight)

For Lesser Tuberosity Osteotomy:

1. Fragment Position: Bone wafer with subscapularis insertion placed back to anatomic position
2. Fixation: 2-3 screws (3.5mm cortical or 4.0mm cancellous) through fragment into shaft
3. Compression: Lag technique if bone quality good (interfragmentary compression)

Rotator Interval Closure:

• Repair subscapularis superior border to supraspinatus (re-establishes rotator interval)
• Heavy absorbable suture (0 Vicryl) - mattress technique
• Recreates anterior shoulder stability

Clavipectoral Fascia:

• Usually not repaired (no functional consequence)
• If patient thin: Loose 2-0 Vicryl approximation (cosmesis)

Subcutaneous Closure:

• 2-0 Vicryl interrupted sutures (invert skin edges)
• Achieve haemostasis (meticulous - shoulder haematomas are common)

Skin Closure:

• 3-0 Monocryl subcuticular (running) - excellent cosmesis
• Dermabond or Steri-Strips (skin adhesive)
• No drain (unless extensive bleeding - controversial)

Pre-Closure Verification

Implant Position (If Arthroplasty):

• Humeral stem version 20-30° retroversion (from bicipital groove reference)
• Glenoid component or baseplate flush with bone (no proud edges)
• Stability check: Full ROM without dislocation (forward elevation, external rotation, internal rotation)

Haemostasis:

• Anterior circumflex humeral artery controlled (if encountered)
• Cephalic vein intact or ligated (no ongoing bleeding)
• Bone bleeding controlled (bone wax if needed - humerus, glenoid)

Instrument Count:

• Needles, sponges, instruments all accounted for (count complete)

Layer-by-Layer Closure

Deep Layers:

1. Subscapularis Repair: Tag sutures through lesser tuberosity drill holes (0 Ethibond × 3-4 sutures)
2. Rotator Interval: Subscapularis to supraspinatus (0 Vicryl × 2 mattress sutures)
3. Conjoined Tendon: If released from coracoid, repair with 0 Vicryl (rarely needed)

Superficial Layers: 4. Deltopectoral Interval: Usually not closed (muscles fall back into place) 5. Clavipectoral Fascia: Optional 2-0 Vicryl (cosmesis only) 6. Subcutaneous: 2-0 Vicryl interrupted × 5-6 sutures 7. Skin: 3-0 Monocryl subcuticular running, Dermabond

Dressing:

• Sterile gauze and ABD pads
• Shoulder immobilizer (sling with abduction pillow if reverse TSA)
• No drain (unless >200mL blood loss during closure)

Intraoperative Complications

Cephalic Vein Injury

• Presentation: Vein avulsion during mobilisation (tethered by tributaries)
• Management:
  • Direct pressure (2 minutes)
  • Ligate proximal and distal ends (3-0 ties)
  • Continue procedure (no functional consequence - collateral venous drainage)
• Prevention: Gentle mobilisation, ligate/cauterise tributaries individually

Axillary Nerve Injury (<1% primary surgery, 5% revision)

• Mechanism: Aggressive inferior dissection, sharp retractor below teres major, direct trauma
• Presentation: Immediate deltoid paralysis (cannot test intraop - patient asleep)
• Management:
  • If nerve transected: Primary repair (microsurgical technique)
  • If nerve stretched: Observation (nerve conduction studies at 6 weeks)
  • EMG at 3 months (denervation potentials if >90% injury)
• Recovery: Neuropraxic (traction) injuries frequently recover over 3-6 months; transection requires surgical repair and has a guarded prognosis
• Prevention: Keep inferior dissection out of the axillary nerve zone (~5cm below greater tuberosity), blunt retractors only inferiorly

Musculocutaneous Nerve Injury (<1%)

• Mechanism: Aggressive medial retraction (brachial plexus stretch), coracoid osteotomy (Latarjet)
• Presentation: Weak elbow flexion, loss of lateral forearm sensation
• Management: Observation (most recover 3-6 months)
• Prevention: Gentle medial retraction, identify nerve if high entry into coracobrachialis

Brachial Plexus Stretch (<1%)

• Mechanism: Prolonged aggressive medial retraction (arm in extension + retraction pulls plexus)
• Presentation: Global arm weakness (multiple nerve territories), burning dysesthesias
• Management:
  • Release retraction immediately
  • Neuro exam at end of case (document)
  • MRI brachial plexus if severe (rule out avulsion)
  • Neurology consult (nerve conduction studies)
• Prevention: Gentle medial retraction, periodic release of retractors

Fracture (During Arthroplasty)

• Greater Tuberosity Fracture (5%): Excessive external rotation during head delivery
  • Management: ORIF with heavy suture (#5) and suture anchors
• Humeral Shaft Fracture (2%): Canal preparation (reaming, broaching) with osteoporotic bone
  • Management: Longer stem (bypass fracture 2 cortical diameters), consider cerclage wires
• Glenoid Fracture (<1%): Baseplate screw penetration (reverse TSA)
  • Management: Change screw direction, consider bone graft

Early Postoperative Complications (0-6 weeks)

Subscapularis Failure (10-20% reverse TSA)

• Presentation: Anterior shoulder pain, inability to lift-off test, positive belly press
• Diagnosis: MRI (tendon discontinuity), ultrasound (dynamic - gap visible)
• Risk Factors: Reverse TSA (tension higher), poor tissue quality, inadequate repair
• Management:
  • Under 3 months + good tissue: Revision repair (re-tag, bone anchors)
  • >3 months or poor tissue: Observe (most compensate with deltoid)
  • Persistent instability: Pectoralis major transfer (Resch technique)

Infection (1-2%)

• Presentation: Persistent pain, fevers, wound drainage, elevated CRP/ESR
• Organisms: Cutibacterium acnes (50% shoulder infections - indolent), Staph aureus (30%)
• Diagnosis:
  • Early (<3 weeks): Wound cultures, blood cultures, CRP/ESR
  • Late (>3 weeks): Aspiration under image guidance (hold antibiotics 2 weeks prior)
• Management:
  • Acute (under 3 weeks): Debridement, modular component (poly) exchange if arthroplasty, retain fixed implants (DAIR), targeted IV then oral antibiotics guided by culture and local microbiology advice
  • Chronic (over 3 weeks): 2-stage revision (explant, antibiotic spacer, re-implant once infection controlled)

Instability (2-5%)

• Anterior Dislocation: Subscapularis failure (most common), component malposition (excessive humeral retroversion)
• Posterior Dislocation: Reverse TSA (glenosphere too posterior), excessive external rotation
• Management:
  • Closed reduction (trial without sedation if recurrent - awake reduction protocol)
  • If recurrent: CT imaging (component version), consider revision (adjust version, constrained liner)

Haematoma (3-5%)

• Presentation: Expanding painful swelling, ecchymosis tracking down arm
• Risk Factors: Anticoagulation (Aspirin, Plavix, warfarin), cephalic vein injury, poor haemostasis
• Management:
  • Small (<50mL): Observe (resorbs over 2-4 weeks)
  • Large (>100mL) or expanding: Evacuation (OR - risk of infection if left)

Late Postoperative Complications (>6 weeks)

Stiffness (5-10%)

• Presentation: Limited ROM (forward elevation <90°, external rotation <20°)
• Risk Factors: Subscapularis overtightening, adhesive capsulitis, inadequate PT
• Prevention: Aggressive PT >6 weeks (PROM → AAROM → AROM progression)
• Management:
  • Under 6 months: Intensive PT (3× per week), consider suprascapular nerve block
  • >6 months: Manipulation under anaesthesia (MUA) ± arthroscopic capsular release

Heterotopic Ossification (HO) (1-3%)

• Presentation: Progressive stiffness (3-6 months postop), ROM plateaus then worsens
• Risk Factors: Male sex, DISH (diffuse idiopathic skeletal hyperostosis), previous HO, neurotrauma
• Diagnosis: X-ray (bone formation in soft tissues anterior to shoulder)
• Prevention: Indomethacin 75mg daily × 6 weeks postop (if high risk)
• Management: Excision if mature (>12 months) AND functionally limiting

Periprosthetic Fracture (1-2%)

• Presentation: Sudden pain, loss of function (usually fall or trauma)
• Diagnosis: X-ray (fracture around stem)
• Classification: Wright-Cofield (Type A: proximal to tip, Type B: at tip, Type C: distal to tip)
• Management:
  • Type A: ORIF (plate, cables, preserve implant)
  • Type B: Revision to longer stem + ORIF
  • Type C: ORIF alone (treat like humeral shaft fracture)

Aseptic Loosening (5-10% at 10 years)

• Presentation: Progressive pain (especially with activity), grinding sensation
• Diagnosis: X-ray (radiolucent lines >2mm, component migration, subsidence)
• Management: Revision arthroplasty (longer stem, bone graft if bone loss)

Immediate Postoperative Care (Day 0-1)

Recovery Room:

• Neurovascular check (axillary nerve function cannot be assessed - deltoid unopposed by rotator cuff)
• Pain control: Interscalene block (12-18 hour duration), oral opioids (oxycodone 5-10mg Q4h PRN)
• X-ray (AP shoulder, axillary lateral - confirm component position, rule out fracture)

Ward Care:

• Shoulder immobilizer (sling ± abduction pillow if reverse TSA)
• Cryotherapy (ice packs 20 min Q2h - reduces swelling, improves pain)
• Gentle hand/wrist/elbow ROM (prevent CRPS, maintain lymphatic drainage)

Discharge Criteria (Day 1-2):

• Pain controlled on oral medications (NRS under 4/10)
• Neurovascularly intact (document radial pulse, sensation)
• Safe mobilization (independent transfers, no orthostatic hypotension from beach chair)
• Understands sling use (immobilization for 6 weeks)

Outpatient Follow-up Protocol

Week 2:

• Wound Check: Remove dressing, assess for infection (erythema, drainage)
• Suture Removal: If non-absorbable skin sutures (most use absorbable - no removal needed)
• X-ray: AP and axillary lateral (confirm component position unchanged)
• Physiotherapy: Pendulum exercises only (gravity-assisted passive ROM)

Week 6:

• X-ray: AP, axillary, scapular Y (assess healing, component position)
• Clinical Exam: ROM (PROM vs AROM), subscapularis function (cannot test yet - healing)
• Physiotherapy Progression:
  • Arthroplasty: PROM → AAROM (pulley exercises)
  • Fracture ORIF: PROM only (protect tuberosity healing)

Week 12:

• X-ray: Assess fracture/osteotomy healing (lesser tuberosity union if osteotomy)
• Subscapularis Testing: Lift-off, belly press, bear hug (strength testing now safe)
• Physiotherapy Progression: AROM exercises, rotator cuff strengthening (light Theraband)

Month 6:

• Final X-ray: Bone ingrowth (reverse TSA baseplate), fracture union
• ROM Goals:
  • Anatomic TSA: Forward elevation 140-160°, external rotation 40-60°
  • Reverse TSA: Forward elevation 120-140°, external rotation 20-30° (ER limited by design)
• Return to Activity: Unrestricted activities of daily living, swimming OK, contact sports AVOID

Physiotherapy Protocol (Evidence-Based)

Phase 1 (Weeks 0-6): Protection

• Goals: Protect subscapularis repair, prevent stiffness
• Exercises:
  • Pendulum exercises (gravity-assisted PROM)
  • Elbow/wrist/hand active ROM (maintain distal function)
  • Scapular retraction (prevent scapular dyskinesis)
• Restrictions: NO active shoulder ROM, NO lifting, sling 24/7 except exercises

Phase 2 (Weeks 6-12): Passive to Active-Assisted ROM

• Goals: Restore PROM, begin AAROM
• Exercises:
  • Supine PROM (PT-assisted forward elevation, external rotation to neutral)
  • Pulley exercises (AAROM - forward elevation)
  • Table slides (AAROM - forward elevation on table surface)
• Restrictions: NO resisted exercises, NO lifting >500g

Phase 3 (Weeks 12-24): Active ROM and Strengthening

• Goals: Full AROM, begin strengthening
• Exercises:
  • Active forward elevation (no weight)
  • Theraband external rotation (light resistance - yellow band)
  • Scapular stabilization (rows, retraction against resistance)
• Restrictions: Avoid overhead lifting >5kg (until month 6)

Phase 4 (Months 6-12): Return to Function

• Goals: Unrestricted ADLs, recreational activities
• Exercises: Progressive resistance (weights up to 10kg), functional activities (reaching, lifting)
• Return to Sport: Swimming OK (avoid butterfly), golf OK (6 months), tennis OK (9 months)

Return to Work and Function (Global Guidance)

Physiotherapy Access: Outcomes after shoulder arthroplasty are strongly dependent on supervised rehabilitation and patient compliance. Arrange a structured PT pathway preoperatively - access and funding vary by health system, but early, protocol-driven therapy is a consistent predictor of better range of motion and function.

Return to Work:

• Sedentary Work: 6-8 weeks (desk-based, no lifting)
• Light Duty: ~3 months (occasional lifting under 5kg)
• Heavy Labour: 6-12 months (overhead work, repetitive lifting) - many do not return to pre-injury work

Driving: Patients should not drive while in a sling or unable to control the vehicle safely - commonly 6-12 weeks for dominant-side surgery. Discuss preoperatively and arrange transport.