import { OnePagerSummary, ExamWarning, InfoCardGrid, InfoCard, MnemonicCard, EvidenceCard, VivaScenarioSection, VivaScenario, ExamCheatSheet, ContentSection, ExamPearl, SafetyAlert, NumberHighlightRow, NumberHighlight, Tabs, Tab, ComparisonTable } from '@/components/mdx' **Location**: Exits quadrilateral space posteriorly, crosses inferior glenohumeral joint capsule 5-7mm inferior to glenoid rim, runs on deep surface of deltoid muscle at level of surgical neck **Protection**: Limit inferior retraction to less than 1cm, stay on bone during inferior capsular release with curved osteotome, avoid prolonged retraction, gentle tissue handling during humeral dislocation **Location**: Enters conjoint tendon (coracobrachialis and short head biceps) 3-8cm distal to coracoid tip (mean 5.5cm), can enter as proximal as 2cm in anatomic variants **Protection**: Never place retractor medial to conjoint tendon, identify conjoint before retraction, limit medial retraction force and duration (less than 90 minutes continuous), retract conjoint as unit not individually **Location**: Runs in deltopectoral interval within fatty triangle, variable anatomy (bifurcation in 15%, large tributaries in 30%), connects to axillary vein superiorly **Protection**: Identify early during interval development, retract laterally with deltoid (85%) or medially with pectoralis (15%), if injured ligate proximally and distally (not just cautery), preservation preferred but sacrifice acceptable if needed for exposure **Location**: Deep and medial to surgical field, posterior to pectoralis minor, anterior to subscapularis muscle, within 2-3cm of surgical plane at glenoid exposure **Protection**: Never retract medial to conjoint tendon, limit depth of glenoid drilling (vault depth 25-30mm average, check preoperative CT), avoid excessive medial retraction during glenoid exposure, use depth gauge before drilling **Location**: Spirals around posterior humerus in spiral groove 14-20cm distal to acromion (average 16cm), at risk during distal humeral canal preparation and retractor placement **Protection**: Limit humeral canal reaming depth to 10-15cm maximum, avoid lateral retractors on distal humerus, gentle technique during stem insertion, awareness of course prevents injury during revision or exposure extension ## Walch Glenoid Classification **Clinical Significance**: Describes glenoid morphology in primary osteoarthritis based on shape, version, and humeral head position - guides surgical strategy for glenoid preparation and component selection. ### Type A: Concentric (Centered Humeral Head) **A1 - Minor Erosion**: Centered humeral head with minor central erosion, normal or slight posterior wear, version typically less than 10° retroversion. **Management**: Standard concentric reaming, standard all-polyethylene component, excellent outcomes. **A2 - Major Central Erosion**: Centered humeral head with major central erosion creating deep concavity, maintained version less than 10°. **Management**: May require deeper reaming to achieve flat surface, risk of excessive bone loss and medialization, consider augmented components if bone stock insufficient. ### Type B: Eccentric (Posterior Subluxation) **B1 - Narrowed Posterior Joint Space**: Asymmetric posterior wear with biconcave appearance, less than 70% posterior subluxation, retroversion typically 10-15°. **Management**: Eccentric reaming (high-side reaming) to correct version, aim for neutral to 5° retroversion final position. **B2 - Posterior Subluxation**: Biconcave glenoid with greater than 70% posterior subluxation, retroversion 10-20°, posterior humeral head erosion. **Management**: Eccentric reaming if bone stock adequate (can correct up to 15° version), consider posterior augmented components or bone grafting if excessive bone loss, may require CT-based planning and patient-specific instrumentation. **B3 - Monoconcave Posterior Defect**: Posterior bone loss creating monoconcave appearance, retroversion greater than 25°, severe posterior humeral head subluxation. **Management**: Eccentric reaming often insufficient (risks vault perforation), posterior bone grafting (autograft from humeral head or allograft), augmented components, or consider reverse TSA if cuff compromise develops. ### Type C: Dysplastic **Glenoid Dysplasia**: Retroversion greater than 25° with dysplastic anatomy, biconcave or monoconcave morphology, often congenital or developmental. **Management**: Complex reconstruction, often requires bone grafting, augmented components, or reverse TSA. Anatomic TSA outcomes inferior - consider alternative strategies. ### Surgical Decision Algorithm **Retroversion less than 10°**: Standard concentric reaming, all-polyethylene component. **Retroversion 10-20°**: Eccentric reaming (high-side) to correct version, monitor bone stock, acceptable to leave 5-10° retroversion if bone preservation needed. **Retroversion greater than 20°**: Bone grafting (structural autograft or allograft), augmented/stepped components, or consider reverse TSA if cuff questionable. **Key Exam Point**: Examiners expect detailed knowledge of classification, ability to identify types on radiographs/CT, and articulate management strategy for B2/B3 glenoids including alternative options and expected outcomes. ## Critical Surgical Anatomy ### Deltopectoral Interval **Internervous Plane**: True internervous interval between deltoid (axillary nerve C5-C6) and pectoralis major (medial and lateral pectoral nerves C5-T1). No muscle division required - safe approach with minimal denervation risk. **Cephalic Vein**: Landmark structure in fatty triangle between muscles, variable anatomy (bifurcation 15%, absent 2%), connects to axillary vein, retract laterally (preferred) or medially based on size and tributaries. **Boundaries**: Superior - clavicle and coracoid, inferior - insertion of pectoralis major on humerus, lateral - deltoid origin and insertion, medial - pectoralis major origin. ### Subscapularis Muscle **Origin**: Subscapular fossa on anterior scapula, covers entire fossa. **Insertion**: Lesser tuberosity via broad tendinous insertion, contributes to anterior joint capsule, superior subscapularis contributes to rotator interval. **Function**: Internal rotation (primary), anterior stabilizer (prevents anterior translation and dislocation), depresses humeral head during elevation. **Nerve Supply**: Upper and lower subscapular nerves (C5-C6) from posterior cord, enter muscle posteriorly on subscapular surface. **Critical Anatomy**: Axillary nerve crosses inferior capsule 5-7mm below inferior glenoid margin - at risk during subscapularis release and inferior capsular release. Anterior humeral circumflex vessels run along inferior subscapularis border - control for hemostasis. ### Glenoid Bone Anatomy **Dimensions**: Average glenoid height 35-40mm, width 25-30mm (pear-shaped), vault depth 25-30mm (highly variable, check preoperative CT). **Version**: Normal 2-7° retroversion (range -7° anteversion to +10° retroversion), measured relative to scapular body axis. **Inclination**: Normal 5° superior inclination, excessive inclination (greater than 10°) predisposes inferior glenoid loosening. **Bone Stock**: Subchondral bone supports component, trabecular bone provides cement interdigitation, cortical rim critical for stability. **Neurovascular Relationships**: Suprascapular nerve 2cm medial to glenoid rim at superior margin (suprascapular notch), axillary nerve 5-7mm inferior to inferior rim, brachial plexus and axillary vessels 2-3cm medial to glenoid face. ### Humeral Anatomy **Anatomic Neck**: True articular margin, 130-140° angle with shaft, 20-30° retroversion relative to transepicondylar axis. **Version Reference**: Bicipital groove is anterior reference (25-35° medial to transepicondylar axis), forearm with elbow 90° flexed is practical intraoperative reference. **Canal Dimensions**: Proximal metaphysis wide and cancellous, diaphysis narrows distally, average canal diameter 8-12mm at isthmus, significant variation requires multiple stem sizes available. **Rotator Cuff Insertions**: Supraspinatus - superior facet greater tuberosity, infraspinatus - middle facet, teres minor - inferior facet, subscapularis - lesser tuberosity. ## Biomechanical Principles ### Joint Stability **Anatomic TSA Stability**: Depends on soft tissue balance (rotator cuff, capsule), component positioning (version, inclination), and joint conformity (matching radii of curvature). **Concavity-Compression**: Glenoid concavity creates stabilizing force when humeral head compresses into socket - less conforming than reverse TSA, relies more on soft tissue. **Rotator Cuff**: Dynamic stabilizers - subscapularis anteriorly, infraspinatus and teres minor posteriorly, supraspinatus superiorly - cuff integrity essential for anatomic TSA (unlike reverse TSA). ### Component Loading **Glenoid Forces**: Eccentric loading from humeral head, maximum forces 2-3x body weight during active elevation, resultant force oriented superiorly and posteriorly (rocking horse mechanism). **Loosening Mechanism**: Eccentric loading causes rocking motion, micromotion at bone-cement interface, cement fatigue, radiolucent line progression, eventual loosening. **Version Effect**: Excessive retroversion increases posterior eccentric loading and accelerates posterior loosening, anteversion increases anterior loading. ### Soft Tissue Tensioning **Joint Constraint**: Anatomic TSA is unconstrained (relies on soft tissue), requires appropriate capsular tension for stability without overstuffing. **Overstuffing**: Excessive soft tissue tension from oversized components or osteotomy malposition causes pain, stiffness, increased glenoid stress, accelerated loosening. **Understuffing**: Insufficient tension causes instability, subluxation, dislocation (especially if subscapularis fails). **Optimal Tension**: Moderate resistance to translation in all directions, able to translate humeral head 25-50% of glenoid diameter with manual stress. ## Subscapularis Management Options ### Lesser Tuberosity Osteotomy (Preferred) **Technique**: 5-7mm bone wafer including subscapularis insertion, oscillating saw parallel to articular surface, preserve bone quality for healing, tag with three #5 nonabsorbable sutures through drill holes. **Advantages**: Bone-to-bone healing (stronger than tendon-to-bone), anatomic repair, failure rate less than 2%, allows earlier mobilization with secure repair, easier to identify and repair anatomically. **Disadvantages**: Risk of tuberosity fracture or nonunion (less than 1%), technically more demanding, requires oscillating saw. **Repair Technique**: Drill three 2mm holes in humeral shaft adjacent to osteotomy, pass #2 or #5 FiberWire or Ethibond through holes and bone fragment, reduce tuberosity anatomically, tie with arm in 30° internal rotation, secure 6-point repair provides excellent fixation. **Outcomes**: Healing rate 98%, failure rate less than 2%, superior function and strength compared to tendon repair techniques. ### Subscapularis Peel **Technique**: Release subscapularis 5mm lateral to lesser tuberosity insertion using electrocautery or sharp dissection, preserve tendon length, tag with multiple sutures for later repair. **Advantages**: Preserves bone stock, avoids tuberosity fracture risk, familiar to most surgeons. **Disadvantages**: Tendon-to-bone healing less reliable (failure 5%), more difficult to achieve anatomic repair, scar tissue may limit excursion. **Repair Technique**: Drill holes or suture anchors in lesser tuberosity, pass sutures through tendon, side-to-side repair if tissue quality allows, tie with arm in 30° internal rotation. **Outcomes**: Healing rate 95%, failure rate 5%, functional outcomes slightly inferior to LTO. ### Subscapularis Tenotomy **Technique**: Divide subscapularis at tendon-muscle junction (2-3cm medial to insertion), allows maximal mobilization but poorest healing potential. **Advantages**: Maximal mobilization, useful in revision or stiff shoulders, fastest release technique. **Disadvantages**: Tendon-to-tendon or tendon-to-muscle healing unreliable (failure 10-15%), difficult to achieve anatomic length, highest instability risk. **Repair Technique**: Side-to-side repair with multiple interrupted sutures, often difficult to achieve tension-free repair, prolonged protection required. **Outcomes**: Healing rate 85-90%, failure rate 10-15%, highest complication rate - avoid in primary TSA unless necessary for exposure. ## Glenoid Component Options ### All-Polyethylene Pegged Components (Standard) **Design**: Ultra-high molecular weight polyethylene (UHMWPE), central peg plus 3-4 peripheral pegs, various conformity options (flat, curved, semi-constrained). **Advantages**: Best long-term survival data (95% 10-year survival AOANJRR), proven track record (gold standard), radiolucent allows assessment of bone-cement interface, cost-effective. **Disadvantages**: Polyethylene wear over time (less concern in low-demand shoulder vs hip/knee), cement fixation potentially less durable in young active patients. **Cementing Technique**: Pressurization critical, pulse lavage and dry surface, cement in dough phase, pressurize into peg holes, maintain pressure until hardened. ### All-Polyethylene Keeled Components **Design**: Single central keel (anterior-posterior orientation) for fixation, requires saw or burr to create keel slot. **Advantages**: Simpler instrumentation (fewer peg holes), traditional design with long track record. **Disadvantages**: Keel orientation may not match optimal fixation axis, stress concentration at keel tip, slightly higher loosening rates than pegged designs in some registries. ### Metal-Backed Components (Avoid) **Design**: Metal baseplate with polyethylene insert, theoretically allows modularity and improved fixation. **Advantages**: Modularity (change polyethylene insert without removing baseplate - theoretical), improved stress distribution (theoretical). **Disadvantages**: High failure rates (15-25% 10-year), screw loosening, polyethylene wear from reduced thickness, dissociation of poly insert, expensive - AVOID in primary TSA. **Evidence**: Multiple studies and registry data show inferior outcomes compared to all-polyethylene components, no longer recommended except specific revision scenarios. ### Augmented/Stepped Components **Indication**: Walch B2/B3 glenoids with posterior bone loss where eccentric reaming insufficient or risks excessive medialization. **Design**: Anterior-posterior stepped or wedge configuration compensates for bone deficiency, available in metal-backed or all-polyethylene versions. **Advantages**: Corrects version without excessive reaming, preserves bone stock, addresses significant defects (greater than 10mm). **Disadvantages**: Limited long-term data, technically demanding, higher cost, some designs metal-backed (higher failure potential). **Technique**: Position component with augment posteriorly to fill defect, standard cementing, ensure adequate bone contact for support. ## Humeral Component Options ### Press-Fit Metaphyseal Stems **Design**: Proximal metaphyseal filling with cancellous bone engagement, various geometries (straight, curved, anatomic), typically short stem (8-12cm). **Advantages**: Bone preservation, easier revision if needed (no cement removal), current trend in primary TSA, good outcomes in adequate bone quality. **Disadvantages**: Requires good bone quality, risk of subsidence in osteoporotic bone, stress shielding concerns (theoretical). **Technique**: Sequential canal preparation, size for proximal fill not distal cortical engagement, version control during insertion, impact gently to avoid fracture. ### Cemented Stems **Design**: Traditional smooth or textured stems requiring cement fixation, typically longer (12-15cm) for distal fixation. **Advantages**: Reliable fixation in poor bone quality (osteoporosis, rheumatoid arthritis), proven long-term data (95% survival 15 years), allows correction of version intraoperatively. **Disadvantages**: Revision more difficult (cement removal), bone cement implantation syndrome risk (rare in shoulder), permanent fixation. **Technique**: Canal preparation with reamers, cement restrictor 2cm past stem tip, retrograde cement injection, stem insertion with version control, maintain pressure until set. ### Stemless Humeral Components **Design**: Metaphyseal fixation only without intramedullary stem, relies on cancellous compression and peripheral bone support. **Advantages**: Maximal bone preservation, simplified revision, no stress shielding, no canal preparation needed. **Disadvantages**: Limited indications (good bone quality, non-dysplastic anatomy), higher subsidence and loosening rates in some studies, technically demanding positioning. **Technique**: Minimal humeral head resection, metaphyseal preparation with compression screws or pegs, critical to achieve initial stability. ## Registry Data ### AOANJRR (Australian Orthopaedic Association National Joint Replacement Registry) **2023 Data - Anatomic TSA**: - Overall revision rate 6.2% at 10 years (all indications) - Primary osteoarthritis revision rate 4.8% at 10 years - Rheumatoid arthritis revision rate 7.3% at 10 years - Revision most common for glenoid loosening (35%), instability (22%), infection (15%) **Component Survival**: - All-polyethylene glenoid: 95% survival 10 years - Metal-backed glenoid: 82% survival 10 years (significantly worse, avoid) - Cemented humeral stem: 96% survival 10 years - Press-fit humeral stem: 94% survival 10 years (shorter follow-up) **Age Effect**: - Age less than 55: revision rate 12% at 10 years (higher activity, longer life expectancy) - Age 55-64: revision rate 8% at 10 years - Age 65-74: revision rate 5% at 10 years - Age greater than 75: revision rate 4% at 10 years **Conclusion**: Anatomic TSA excellent outcomes in appropriate patients (older, lower activity, intact cuff). All-polyethylene glenoid components superior to metal-backed. Younger patients higher revision risk. ## Key Studies ### Subscapularis Management - Miller et al. JBJS 2011 **Study Design**: Systematic review of subscapularis repair techniques in TSA, 1,952 shoulders, minimum 2-year follow-up. **Results**: Lesser tuberosity osteotomy failure rate 1.9%, subscapularis peel failure rate 4.8%, tenotomy failure rate 10.2%. Subscapularis failure associated with anterior instability (85%), poor functional outcomes, lower patient satisfaction. **Conclusion**: Lesser tuberosity osteotomy superior healing and lower failure rate - preferred technique when technically feasible. ### Walch Classification - Walch et al. JSES 1999 **Study Design**: Prospective analysis of 113 osteoarthritic shoulders, CT assessment of glenoid morphology, correlation with outcomes after TSA. **Results**: Type A (concentric) 59%, Type B (eccentric) 32%, Type C (dysplastic) 9%. B2 glenoids (greater than 70% subluxation) higher loosening rate without correction of retroversion. Standard reaming of B2/B3 glenoids resulted in excessive bone loss and medialization. **Conclusion**: Glenoid morphology classification essential for surgical planning. B2/B3 glenoids require alternative strategies (eccentric reaming, augments, grafting) to correct version without excessive bone loss. ### Glenoid Version - Iannotti et al. JSES 2005 **Study Design**: Biomechanical study and clinical correlation of glenoid version effect on component loading and loosening, 89 patients. **Results**: Every 10° increase in retroversion increased posterior eccentric loading by 35%, loosening rate increased significantly with version greater than 10° retroversion. Ideal version neutral to 5° retroversion for optimal loading and longevity. **Conclusion**: Glenoid version correction critical for component survival. Acceptable to leave up to 10° retroversion if bone preservation needed, but neutral preferred. Greater than 10° retroversion unacceptable - use alternative strategies. ### Humeral Component Version - Boileau et al. JBJS 2008 **Study Design**: CT analysis of 75 anatomic TSA, correlation between humeral version and clinical outcomes, minimum 3-year follow-up. **Results**: Native humeral retroversion 20-30° (average 24°), excessive retroversion (greater than 40°) associated with posterior instability, inadequate retroversion (less than 10°) associated with anterior impingement and limited external rotation. Optimal version 20-30° retroversion. **Conclusion**: Humeral component version affects stability and range of motion. Target native version (20-30° retroversion) using bicipital groove and epicondylar axis as references. ## Functional Outcomes ### Pain Relief 95% of patients achieve significant pain relief (VAS improvement 6-7 points), predictable outcome in appropriate indications (primary OA, intact cuff). Pain relief maintained long-term (10-15 years) if no complications. ### Range of Motion Average forward elevation improvement 40-60° (from 90-100° to 130-160°), external rotation improvement 20-30°, internal rotation improvement variable (limited by subscapularis scarring). Function plateaus 12-18 months postoperatively. ### Patient Satisfaction 85-90% satisfied or very satisfied with outcomes in primary OA with intact cuff, satisfaction lower with subscapularis failure, instability, or persistent pain from loosening. ### Return to Activities Low-demand activities (swimming, golf, daily activities) achievable in 95%, high-demand activities (overhead sports, heavy labor) limited by component longevity concerns, most surgeons restrict heavy lifting (greater than 25 pounds repetitive). ## Complications - Detailed Analysis **Patient Position**: Beach chair position 30-45° upright, head secured in Mayfield or horseshoe headrest (prevent intraoperative movement), bump under medial scapula for glenoid exposure (improves access to posterior glenoid), arm free-draped allowing full mobility, table articulation to upright position optimizes glenoid visualization. **Surgical Approach**: Deltopectoral approach - gold standard internervous interval for anatomic TSA, provides excellent humeral and glenoid exposure, minimal muscle denervation risk. **Incision**: Curvilinear incision 12-15cm from coracoid to deltoid insertion, start 2cm lateral and 2cm inferior to coracoid tip (avoids coracoid stress fracture from retractor pressure), curve distally following deltopectoral groove to end 4cm distal to anterior axillary crease, landmarks palpable before incision. **Anesthesia**: General anesthesia with controlled hypotension (reduces bleeding, improves visualization), interscalene block for postoperative analgesia (caution - phrenic nerve palsy in 5%, avoid bilateral blocks), short-acting paralysis allows neuromonitoring if available. **Antibiotics**: Cefazolin 2g IV within 60 minutes before incision (vancomycin 15mg/kg if penicillin allergy or MRSA risk), redose cefazolin every 4 hours intraoperatively if case exceeds duration, continue 24 hours postoperatively (single dose adequate per guidelines but institutional variation). ### Step 1: Skin incision from coracoid to deltoid insertion (12-15cm) Skin incision from coracoid to deltoid insertion (12-15cm): Start 2cm lateral and 2cm inferior to coracoid tip, curve distally following deltopectoral groove to end 4cm distal to anterior axillary crease. EXAM KEY: Mark incision with patient upright to account for soft tissue shift when supine/beach chair. Avoid extending too far medially (cephalic vein injury) or laterally (deltoid denervation). Incision length must allow glenoid exposure without excessive retraction - too short causes soft tissue trauma and poor visualization. **Technical Tip**: EXAM KEY: Incision length directly affects visualization and soft tissue trauma. 12cm minimum for primary TSA in average build, 15cm for muscular patients or revision surgery. Confirm anatomical landmarks palpable before incising - coracoid tip, deltopectoral groove, anterior axillary crease. - Skin necrosis from excessive tension if incision too short - Cephalic vein injury if incision too medial - Deltoid denervation if incision extends too lateral - Inadequate exposure if incision length insufficient ### Step 2: Identify and protect cephalic vein - retract laterally with deltoid Identify and protect cephalic vein - retract laterally with deltoid: Develop subcutaneous flaps sharply to expose deltopectoral interval. Identify cephalic vein running in fatty triangle between deltoid and pectoralis major. Variable anatomy - may bifurcate (15%), absent (2%), large tributaries (30%). Retract vein laterally with deltoid (85% of cases) or medially with pectoralis (15%) based on size and tributaries. EXAM KEY: Vein injury causes hematoma and increases infection risk. If injured, ligate properly with sutures - do not rely on diathermy alone which often fails postoperatively causing bleeding. **Technical Tip**: EXAM KEY: Some surgeons sacrifice vein routinely to improve exposure (reduces retraction time, simplifies approach), but preservation preferred when possible without compromising exposure. If sacrificed, ligate proximally and distally with 2-0 or 3-0 absorbable suture to prevent bleeding and air embolism. - Cephalic vein avulsion or laceration causing hematoma - Inadequate hemostasis leading to postoperative bleeding - Air embolism if large vein torn (rare, beach chair position) ### Step 3: Develop deltopectoral interval bluntly Develop deltopectoral interval bluntly: Separate deltoid (axillary nerve C5-C6) from pectoralis major (medial and lateral pectoral nerves C5-T1) using finger dissection or blunt instrument (Mayo scissors or curved hemostat). This is a true internervous interval requiring no muscle division - safe approach with minimal denervation risk. EXAM KEY: Stay superficial to coracoacromial ligament initially - do not dive deep too early or risk axillary nerve injury. Blunt dissection follows natural tissue plane - minimal resistance when in correct plane. **Technical Tip**: EXAM KEY: If deltoid partially detaches from clavicle during retraction (common in muscular patients or tight exposure), repair it at closure with transosseous sutures to prevent superior migration of deltoid origin and poor cosmesis. Some surgeons release superior 1-2cm of deltoid from clavicle intentionally to improve exposure, then repair at closure. - Axillary nerve injury if dissection too deep or inferior (nerve 5-7mm below inferior glenoid) - Deltoid or pectoralis denervation if muscle division instead of interval development - Excessive bleeding from muscle injury if sharp dissection used ### Step 4: Release pectoralis major insertion partially if needed for exposure Release pectoralis major insertion partially if needed for exposure: Elevate lateral 2-3cm of pectoralis major from humeral insertion if exposure limited. Use electrocautery to minimize bleeding. Tag with stay suture for later identification and repair. EXAM KEY: Full pectoralis release not needed in most primary cases but essential in revision or stiff shoulders (contracture limits exposure). Repair at closure with transosseous bone tunnels if released greater than 50% - failure to repair causes cosmetic deformity and weakness. **Technical Tip**: EXAM KEY: Pectoralis release improves inferior humeral exposure and allows better canal preparation and cement removal in revision. Balance exposure needs against soft tissue trauma. Assess need after deltopectoral interval developed - if adequate exposure without release, preserve insertion. Tag released tendon with heavy suture (0 or #2 Ethibond) for easy identification at closure. - Excessive bleeding from pectoralis major muscle belly - Anterior circumflex humeral vessels at inferior border require control - Loss of pectoralis tendon if not tagged (difficult repair at closure) ### Step 5: Identify and protect conjoint tendon (coracobrachialis and short head biceps) medially Identify and protect conjoint tendon (coracobrachialis and short head biceps) medially: Palpate firm strap-like structure medially - this is the conjoint tendon with musculocutaneous nerve entering at variable level (3-8cm distal to coracoid, mean 5.5cm). Retract medially with Hohmann or deep deltopectoral retractor. EXAM KEY: Never place retractor medial to conjoint - risks musculocutaneous nerve injury causing biceps weakness (flexion and supination) and lateral forearm numbness. Retractor lateral to conjoint, medial edge of retractor against conjoint, medial retraction of conjoint as unit protects nerve. **Technical Tip**: EXAM KEY: In 85% of patients, musculocutaneous nerve enters conjoint 5-6cm distal to coracoid tip (range 3-8cm, outliers 2cm). Excessive medial retraction or prolonged retraction (greater than 90-120 minutes continuous) causes neuropraxia. Release retractor periodically if case prolonged to allow nerve reperfusion. Nerve injury typically recovers 3-6 months but causes significant patient distress and medicolegal concern. - Musculocutaneous nerve injury from medial retractor placement or excessive medial retraction force - Neuropraxia from prolonged retraction duration (greater than 2 hours) - Brachial plexus stretch injury if excessive medial retraction combined with arm manipulation ### Step 6: Release subscapularis via lesser tuberosity osteotomy or tendon peel Release subscapularis via lesser tuberosity osteotomy or tendon peel: SUBSCAPULARIS MANAGEMENT OPTIONS: (1) Lesser tuberosity osteotomy (PREFERRED): 5-7mm bone wafer including subscapularis insertion, oscillating saw parallel to articular surface starting at superior edge of subscapularis insertion, complete osteotomy with osteotome inferiorly, preserve bone quality for healing, tag with three #5 nonabsorbable sutures (FiberWire or Ethibond) through pre-drilled holes in bone fragment. (2) Tendon peel: release 5mm lateral to subscapularis insertion on lesser tuberosity using electrocautery or sharp dissection, tag with multiple sutures. (3) Subscapularis tenotomy: divide tendon-muscle junction 2-3cm medial to insertion - poorest healing but maximal mobilization. EXAM KEY: Lesser tuberosity osteotomy allows strongest repair (bone-to-bone healing) and best healing (less than 2% failure) - preferred technique for primary TSA. Subscapularis failure post-TSA causes anterior instability and poor outcomes. **Technical Tip**: EXAM KEY: Subscapularis failure post-TSA is devastating - causes anterior instability, recurrent dislocation, pain, poor function. Secure repair essential. Know examiners may ask to justify approach choice and describe repair technique in detail. Outcomes data: LTO failure less than 2%, peel 5%, tenotomy 10-15%. LTO allows earlier mobilization (4 weeks vs 6 weeks) due to superior fixation strength. - Excessive bone removal (greater than 7mm wafer) weakens tuberosity and increases fracture risk - Axillary nerve injury during inferior release (nerve 5-7mm below glenoid) - Anterior circumflex humeral vessels at inferior subscapularis border require control - Tuberosity fracture if osteoporotic bone or aggressive osteotomy technique ### Step 7: Perform 360° circumferential capsular release Perform 360° circumferential capsular release: Release capsule from glenoid rim circumferentially: (1) Superior - release rotator interval (between subscapularis and supraspinatus), coracohumeral ligament, superior capsule from glenoid. (2) Anterior - already released with subscapularis. (3) Inferior - release inferior capsule from 3-6 o'clock position on glenoid with curved osteotome, stay on bone to avoid axillary nerve (5-7mm inferior to glenoid rim). (4) Posterior - capsulotomy with electrocautery, release adhesions, tag posterior cuff for later identification. EXAM KEY: Inadequate release prevents humeral head dislocation and glenoid visualization, making surgery unnecessarily difficult and increasing soft tissue trauma from forced retraction. Complete release allows atraumatic dislocation. **Technical Tip**: EXAM KEY: Inferior release is most critical and most commonly inadequate. Use curved osteotome (not straight) staying on glenoid bone to avoid axillary nerve 5-7mm inferior to inferior glenoid rim. Palpate nerve if concerned - strap-like structure inferior and medial to inferior glenoid. Complete inferior release marked by ability to dislocate humeral head anteriorly with minimal force. If difficult, reassess inferior release before forcing. - Axillary nerve injury during inferior capsular release (most common site of nerve injury) - Suprascapular nerve injury during superior release if dissection extends too far medially (nerve 2cm medial to superior glenoid in suprascapular notch) - Humeral fracture if forced dislocation before adequate capsular release - Rotator cuff tear if aggressive superior or posterior release ### Step 8: Dislocate humeral head anteriorly with external rotation and extension Dislocate humeral head anteriorly with external rotation and extension: Apply gentle longitudinal traction with arm in neutral rotation, then external rotation 20-30° and extension 20-30°. Head should deliver anterior to glenoid with minimal force if adequate soft tissue release. If difficult: (1) Reassess and complete inferior capsule release. (2) Release posterior capsule further. (3) Place bone hook on posterior humeral neck to lever head anteriorly. EXAM KEY: Never force dislocation - risks humeral fracture (especially osteoporotic bone, previous fracture, or rheumatoid arthritis), greater tuberosity avulsion, or rotator cuff tear. If cannot dislocate with gentle manipulation, reassess soft tissue releases - inadequate release is cause. **Technical Tip**: EXAM KEY: In osteoporotic bone (T-score less than -2.5) or previous proximal humerus fracture, risk of iatrogenic humeral shaft fracture during dislocation is 1-3%. Gentle technique essential - longitudinal traction first to disengage joint, then rotation and translation. Consider prophylactic humeral cerclage wire before dislocation in very poor bone quality if high concern for fracture. Assistant controls scapula to prevent levering forces on humerus. - Iatrogenic humeral shaft fracture (metaphyseal or diaphyseal) from forced dislocation - Greater tuberosity avulsion fracture from excessive external rotation force - Rotator cuff tear (supraspinatus or infraspinatus) from forced manipulation - Glenoid fracture (rare) if levering forces transmitted to glenoid ### Step 9: Assess glenoid version, inclination, and bone loss using preoperative CT data Assess glenoid version, inclination, and bone loss using preoperative CT data: Inspect glenoid for: (1) Version - measure with glenoid version guide referenced to scapular body (normal 2-7° retroversion, range -7° anteversion to +10° retroversion). (2) Bone loss - posterior erosion (Walch B2/B3) or anterior defects, measure depth and extent. (3) Inclination - superior inclination (normal 5°) predisposes inferior loosening, excessive inclination requires correction. EXAM KEY: Preoperative CT planning essential for severe deformity (Walch B2/B3, version greater than 15°, bone loss greater than 10mm). Walch B2 glenoid (greater than 10° retroversion, posterior subluxation greater than 70%) needs eccentric reaming or augmented components - standard reaming causes excessive medialization and bone loss. **Technical Tip**: EXAM KEY: Glenoid component malposition is leading cause of early loosening. Version should be corrected to neutral or slight retroversion (0-10°, ideally 0-5°). Know Walch classification in detail and be able to identify on imaging: A1/A2 (concentric, minor/major central erosion), B1/B2 (posterior subluxation less than/greater than 70%, biconcave), B3 (monoconcave posterior bone loss greater than 25° retroversion), C (dysplastic, retroversion greater than 25°). Management strategy differs for each type. - Failure to recognize severe version or bone loss leading to component malposition - Excessive reaming of B2/B3 glenoids causing medialization, bone loss, and vault perforation - Under-correction of version leaving excessive retroversion (greater than 10°) causing accelerated loosening ### Step 10: Prepare humeral osteotomy site by removing osteophytes and exposing anatomic neck Prepare humeral osteotomy site by removing osteophytes and exposing anatomic neck: Remove all peripheral osteophytes circumferentially with rongeur or oscillating saw to identify true anatomic neck. Place humeral cutting guide using: (1) Bicipital groove for version reference (20-30° retroversion relative to epicondylar axis). (2) Medullary canal axis for varus/valgus alignment (130-140° to shaft axis). (3) Templated height for head size restoration and soft tissue tensioning. EXAM KEY: Osteotomy level determines head height restoration and soft tissue tensioning - critical for stability and function. Cutting too proud (high) causes overstuffing, pain, limited motion, early loosening from excessive joint reactive forces. Cutting too low causes instability, inferior subluxation, limited function. **Technical Tip**: EXAM KEY: Osteotomy height is one of most critical technical factors. Use anatomic landmarks: natural anatomic neck (visible groove at articular margin after osteophyte removal), greater tuberosity superior edge (1cm superior to anatomic neck), medial calcar (intact in primary OA, may be eroded in inflammatory or post-traumatic). Templating from preoperative radiographs helps estimate appropriate cut level. Error toward slightly lower cut (easier to add head height with thicker component than remove bone after cutting too high). - Cutting too proximal (proud) causing overstuffing and accelerated component failure - Cutting too distal (low) causing instability and limited function - Damage to greater or lesser tuberosity during osteophyte removal - Canal perforation if aggressive osteophyte removal extends into metaphysis ### Step 11: Perform humeral head osteotomy with oscillating saw at 130-140° to shaft axis, 20-30° retroversion Perform humeral head osteotomy with oscillating saw at 130-140° to shaft axis, 20-30° retroversion: Execute osteotomy with oscillating saw following cutting guide. Check cut with trial components for: (1) Coverage of cut surface by head trial (want greater than 70% coverage). (2) Soft tissue tension in neutral position (moderate resistance to translation). (3) No bone-bone impingement of peripheral osteophytes. EXAM KEY: Version referenced to forearm with elbow 90° flexed - 20-30° retroversion means cutting guide oriented 20-30° posterior to forearm axis (forearm represents epicondylar axis orientation). Bicipital groove is 25-35° medial to epicondylar axis - useful intraoperative reference. **Technical Tip**: EXAM KEY: Excessive retroversion (greater than 40°) causes posterior instability and dislocation. Inadequate retroversion (less than 10°) causes anterior impingement with arm at side (loss of external rotation) and limited overhead reach. Average native retroversion 20-30° (range 10-40°) - goal is restore native anatomy. Use bicipital groove (mark with methylene blue or suture) and forearm position as references. Assistant maintains arm position during cut to prevent version error. - Version error from improper cutting guide orientation or arm rotation during cutting - Humeral shaft fracture propagation if osteoporotic bone or aggressive sawing - Incomplete cut requiring reaming or additional sawing (creates irregular surface) - Greater tuberosity injury if saw extends laterally ### Step 12: Prepare humeral canal with sequential reamers to depth 10-15cm Prepare humeral canal with sequential reamers to depth 10-15cm: Insert canal finder to identify canal axis (avoid varus/valgus malalignment). Ream sequentially with increasing sizes (typically start 6mm, progress to 10-14mm) until cortical chatter (tactile and auditory feedback of cortical engagement). Stop when firm cortical engagement achieved - over-reaming risks fracture, under-reaming prevents stem seating. EXAM KEY: Use hand reamers (not power) for better tactile feedback and control in osteoporotic bone - power reamers increase fracture risk. Reaming depth 10-15cm maximum - radial nerve spirals around humerus at 14-20cm from acromion, deeper reaming risks nerve injury. **Technical Tip**: EXAM KEY: Humeral canal anatomy varies significantly - some patients have narrow canals (8-10mm) requiring smaller stems, others have wide capacious canals (14-16mm). Have multiple stem sizes available. Modern press-fit stems achieve fixation through proximal metaphyseal filling (cancellous compression) not distal cortical engagement - proximal fill more important than distal fixation for stability and load transfer. Cemented stems require distal canal preparation for cement mantle. - Humeral shaft fracture from over-reaming or excessive force in osteoporotic bone - Canal perforation from varus/valgus malalignment during reaming - Radial nerve injury if reaming depth exceeds 15cm - Thermal necrosis if power reaming used excessively (less concern with hand reamers) ### Step 13: Prepare glenoid: expose face, ream concentrically to remove all cartilage and subchondral bone Prepare glenoid: expose face, ream concentrically to remove all cartilage and subchondral bone: GLENOID EXPOSURE: Place Fukuda or similar glenoid retractor behind humerus retracting posteriorly (protects axillary nerve). Anterior and posterior Hohmann retractors on glenoid rim. Assistant provides humeral traction and rotation to optimize visualization. REAMING: (1) Identify glenoid face center (intersection of AP and SI axes). (2) Start with smallest reamer perpendicular to glenoid face (not scapular body). (3) Ream concentrically progressing to larger sizes until all cartilage removed and uniform bleeding cancellous bone exposed. (4) Check version with guide - should be 0-10° retroversion maximum. EXAM KEY: Reaming corrects version but excess reaming causes bone loss and medialization (weakens fixation, increases joint reactive forces). Goal: minimal bone removal while achieving complete cartilage clearance and correct version (0-10° retroversion). **Technical Tip**: EXAM KEY: Walch B2/B3 glenoids with greater than 15° retroversion: eccentric reaming (high-side reaming - anterosuperior) or augmented/stepped components. Eccentric reaming can correct up to 15° version but risks vault perforation if excessive. Never accept greater than 10° retroversion in final position - accelerated loosening. If cannot correct to less than 10° with safe reaming (vault adequate depth, no perforation risk), use augmented component or consider bone grafting. Alternative: reverse TSA if cuff questionable or severe bone loss. - Vault perforation from excessive reaming depth or eccentric reaming in thin vault (neurovascular injury) - Glenoid fracture from excessive reaming force or poor bone quality - Under-reaming leaving cartilage islands (poor cement interdigitation and fixation) - Excessive medialization from over-reaming (increases joint reactive forces and loosening risk) ### Step 14: Create central peg/keel hole and peripheral peg holes with drill guides Create central peg/keel hole and peripheral peg holes with drill guides: Use component-specific drill guides ensuring perpendicular orientation to glenoid face. PEGGED COMPONENTS: Drill central hole 20-25mm depth plus 4 peripheral holes 15-20mm depth using drill guide. KEELED COMPONENTS: Create central keel slot with saw or high-speed burr 20-25mm depth. EXAM KEY: Hole depth critical - too shallow prevents component seating (proud component, instability, accelerated wear), too deep risks vault perforation and neurovascular injury (brachial plexus and axillary vessels 2-3cm medial to glenoid). Vault depth average 25-30mm but highly variable (range 15-40mm) - check preoperative CT and use depth gauge intraoperatively before drilling. **Technical Tip**: EXAM KEY: Preoperative CT shows vault depth and version in 3D - essential for surgical planning especially in dysplastic or eroded glenoids. Use depth gauge to confirm adequate bone stock before drilling each hole. If vault thin (less than 15mm remaining after reaming), consider stemless humeral component only (hemiarthroplasty) or reverse TSA. Drilling posterior holes in B2/B3 glenoids highest risk of perforation due to posterior bone loss - reduce depth or omit posterior peripheral peg if vault inadequate. - Vault perforation causing neurovascular injury (brachial plexus, axillary vessels, suprascapular vessels) - Glenoid fracture if drill binds or excessive force applied - Component malposition if drill guide not perpendicular to glenoid face - Inadequate depth causing proud component and accelerated wear ### Step 15: Cement glenoid component with pressurization technique Cement glenoid component with pressurization technique: CEMENTING TECHNIQUE: (1) Pulse lavage glenoid surface (remove debris, blood, bone particles) and dry with gauze sponges on suction (completely dry surface essential for cement interdigitation). (2) Mix cement (low viscosity bone cement preferred for better penetration) and wait until dough phase consistency (not liquid - runs out, not hard - won't pressurize). (3) Place cement in peg/keel holes using pressurizer syringe or finger pressure (fill completely, express air). (4) Apply thin layer (2-3mm) to component back surface. (5) Insert component and pressurize with impactor maintaining perpendicular orientation until fully seated and cement extrudes peripherally (confirms pressurization and complete seating). (6) Remove excess cement meticulously with curette (especially posterior - cement debris causes pain and glenoid irritation). (7) Maintain impactor pressure until cement hardens (8-10 minutes - prolonged time but essential for fixation). EXAM KEY: Radiolucent lines less than 1.5mm around glenoid are acceptable (stress shielding, normal adaptation); lines greater than 2mm indicate loosening risk or poor initial fixation. **Technical Tip**: EXAM KEY: Cement pressurization improves cement interdigitation into trabecular bone and fixation strength. Unpressurized cement has significantly lower pull-out strength and higher early loosening rates. All-polyethylene pegged components have best long-term survival data (95% 10-year survival AOANJRR) superior to keeled (92% 10-year) and significantly better than metal-backed components (82% 10-year - avoid). Use standard low viscosity bone cement (Simplex, Palacos) not antibiotic-loaded cement routinely in primary surgery. - Component malposition if not fully seated or tilted during insertion - Cement extrusion posteriorly causing glenoid irritation, pain, nerve irritation - Air pockets in cement causing weak fixation points - Premature cement hardening before component fully seated (timing critical) - Thermal necrosis of bone from cement polymerization (theoretical concern, rarely clinically significant) ### Step 16: Trial humeral components - check head size, offset, stability through ROM Trial humeral components - check head size, offset, stability through ROM: Assemble trial stem plus trial head (multiple sizes available typically 38-52mm diameter). Assess: (1) Head coverage of osteotomy surface (want greater than 70% coverage - incomplete coverage causes edge loading). (2) Joint reduction tension (should be moderate - firm resistance to translation but not excessively tight, able to translate 25-50% of glenoid diameter with manual stress). (3) Stability through full ROM - no subluxation or dislocation with ROM to limits (forward elevation 150°, external rotation 40°, internal rotation to L3). (4) Impingement-free motion (no bone-bone contact, soft tissue impingement). (5) Arm length restoration (compare to contralateral, assess soft tissue tension). EXAM KEY: If unstable, consider: larger head diameter, more head offset, check soft tissue repair (subscapularis). If too tight (overstuffed): smaller head, less offset, check osteotomy level (may need to lower cut if excessive). Component selection directly affects outcomes - overstuffing is common error leading to pain, stiffness, accelerated loosening. **Technical Tip**: EXAM KEY: Head size selection balances coverage (want maximum to avoid edge loading) and soft tissue tension (avoid overstuffing). Most patients use 44-50mm heads. Overstuffing defined as excessive soft tissue tension preventing easy ROM, causes pain, stiffness, early loosening from increased joint reactive forces. Clinical signs: difficult reduction requiring force, cannot achieve ROM, soft tissues blanch from tension. If overstuffed, must address - downsize head, check osteotomy level, assess glenoid position. - Inadequate reduction assessment leading to postoperative instability - Overstuffing not recognized causing pain and stiffness - Trial component disassembly or fracture during trialing - Iatrogenic fracture from excessive force during ROM testing ### Step 17: Insert final humeral stem - cemented or press-fit based on bone quality and stem design Insert final humeral stem - cemented or press-fit based on bone quality and stem design: PRESS-FIT TECHNIQUE (for modern metaphyseal-filling stems in good bone quality): Clean canal with pulse lavage, dry with gauze. Assemble final stem and head. Impact stem incrementally with mallet checking version alignment after each impact (reference bicipital groove mark and forearm position). Achieve solid seating with firm cortical contact (tactile and auditory feedback changes when fully seated). CEMENTED TECHNIQUE (for older smooth stems or poor bone quality - osteoporosis, inflammatory arthritis, revision): Brush canal, pulse lavage, dry with gauze on sucker. Insert cement restrictor 2cm past planned stem tip. Inject cement retrograde (distal to proximal) with cement gun until canal filled to osteotomy level. Insert stem with steady pressure maintaining version (assistant stabilizes arm, mark bicipital groove for reference). Hold steady pressure until cement sets (8-10 minutes). EXAM KEY: Modern trend toward press-fit metaphyseal stems - easier extraction if revision needed, avoid cement removal, good outcomes in primary surgery with adequate bone. Cement still preferred for osteoporotic bone (T-score less than -2.5) or older smooth stems requiring distal fixation. **Technical Tip**: EXAM KEY: Version control critical during insertion - humeral component malposition (excessive retroversion or anteversion) causes instability. Mark bicipital groove with methylene blue or colored suture before stem insertion. Assistant holds arm in neutral rotation (elbow 90°, forearm vertical) while stem inserted and impacted. Surgeon checks bicipital groove alignment frequently - should be 25-35° medial to forearm (aiming for 20-30° retroversion relative to epicondylar axis). Common error: arm drifts into rotation during insertion causing version error. - Humeral shaft fracture from over-impaction of press-fit stem or oversized stem - Version malposition causing instability (excessive retroversion - posterior instability, inadequate retroversion - anterior impingement) - Cement extravasation if excessive cement or inadequate restrictor - Stem subsidence if inadequate press-fit fixation or poor bone quality ### Step 18: Repair subscapularis with transosseous sutures through bone tunnels Repair subscapularis with transosseous sutures through bone tunnels: LESSER TUBEROSITY OSTEOTOMY REPAIR (PREFERRED): (1) Reduce tuberosity fragment anatomically against humeral shaft at original position (avoid medializing). (2) Drill three 2mm holes in humeral shaft adjacent to tuberosity bed exiting laterally on shaft 2-3cm distal to osteotomy. (3) Pass #2 or #5 nonabsorbable sutures (Ethibond, FiberWire) through drill holes from medial to lateral. (4) Pass sutures through drill holes in bone fragment (made at time of osteotomy) and adjacent subscapularis tendon. (5) Reduce arm to 30° internal rotation (neutral too much tension, excessive IR allows laxity). (6) Tie sutures over bone bridge on lateral shaft with solid knots. Results in 6-point repair (3 sutures, 2 limbs each) providing excellent fixation strength. TENDON PEEL REPAIR: Repair tendon to bone using 3-4 suture anchors in lesser tuberosity or transosseous bone tunnels, side-to-side repair if tissue quality allows, tie with arm 30° IR. EXAM KEY: Subscapularis repair strength determines postoperative protocol. Strong repair (LTO) allows earlier motion (passive ROM week 0-4, active week 4-6) than tendon repair (passive only week 0-6, active week 6-12). Failure to protect repair adequately causes failure and instability. **Technical Tip**: EXAM KEY: Subscapularis failure rate 10-15% with tendon tenotomy, 5% with tendon peel, less than 2% with lesser tuberosity osteotomy - LTO clearly superior technique. Repair failure causes anterior instability, recurrent dislocation, pain, poor function - devastating complication requiring revision surgery (often conversion to reverse TSA). Examiners expect detailed knowledge of repair techniques and healing data. Postoperative protocol must protect repair - sling 6 weeks minimum, no active IR strengthening until 12 weeks. - Tuberosity fracture from drill holes too close together or aggressive reduction - Suture pull-through if bone quality poor or sutures tied too tight - Inadequate reduction leading to malposition and altered biomechanics - Axillary nerve injury if sutures placed too inferior or retraction excessive ### Step 19: Repair rotator interval if released, close deltopectoral interval Repair rotator interval if released, close deltopectoral interval: Repair rotator interval (if released - not routine) with interrupted absorbable sutures (2-0 Vicryl) reapproximating subscapularis to supraspinatus/coracoacromial ligament. Do NOT repair deltopectoral interval - allow natural tissue planes to appose without suturing (closure causes compartment syndrome and deltoid denervation). Repair pectoralis major to humerus if released greater than 50% using transosseous sutures or bone tunnels (prevents cosmetic deformity and weakness). EXAM KEY: Closing deltopectoral interval is ERROR causing compartment syndrome (rare but devastating), deltoid denervation (more common), and wound complications. Never close this interval - cardinal rule in deltopectoral approach. **Technical Tip**: EXAM KEY: Some surgeons place suction drain in subacromial space - controversial, no high-quality evidence shows benefit in reducing hematoma or infection in primary TSA. If drain used, remove at 24 hours (prolonged drainage increases infection risk). Drains may increase pain and limit early motion. Current trend away from routine drainage in primary surgery - reserve for revision, anticoagulated patients, or concerning intraoperative bleeding. Meticulous hemostasis superior to drainage. - Compartment syndrome if deltopectoral interval closed (cardinal error) - Deltoid denervation from sutures through muscle or excessive closure tension - Inadequate hemostasis leading to hematoma formation - Lost pectoralis tendon if released and not repaired (cosmetic deformity) ### Step 20: Layered closure: subcutaneous with 2-0 absorbable, skin with subcuticular 3-0 monofilament Layered closure: subcutaneous with 2-0 absorbable, skin with subcuticular 3-0 monofilament: Close subcutaneous tissue in one or two layers with 2-0 Vicryl or Monocryl running or interrupted sutures, eliminate dead space, ensure hemostasis. Avoid closing superficial fascia separately (no benefit, more pain, longer operative time). Close skin with 3-0 or 4-0 Monocryl subcuticular running stitch (better cosmesis, patient preference) or staples (faster but lower satisfaction, more painful removal). Apply sterile dressing (dry gauze and tegaderm or similar) and sling with arm in neutral rotation and slight abduction (pillow or abduction wedge not needed for anatomic TSA). EXAM KEY: Wound closure critical for infection prevention - meticulous technique, avoid dead space, ensure hemostasis, gentle tissue handling. Wound complications (drainage, dehiscence, necrosis) increase infection risk significantly - prevention essential. Consider skin glue overlay for waterproof seal in high-risk patients. **Technical Tip**: EXAM KEY: Skin closure technique affects cosmesis but not infection rate in primary surgery (large registry data shows no difference staples vs subcuticular). Patient satisfaction significantly higher with subcuticular closure (less painful, better appearance, no removal needed). Use staples only if time-critical or skin quality poor (very thin, friable). Subcuticular closure adds 5 minutes but worthwhile for patient experience. Examiners may ask about evidence for closure techniques. - Wound dehiscence from excessive tension or poor tissue quality - Hematoma from inadequate hemostasis (increases infection risk) - Skin necrosis at closure points if sutures too tight or tissue devascularized - Suture abscess or reaction (rare with modern monofilament) **Immediate Post-operative (0-24 hours)**: Recovery room monitoring for neurovascular status (document radial pulse, motor function - deltoid, biceps, wrist/finger extension, sensory testing), pain control (interscalene block typically provides excellent analgesia 12-24 hours), radiographs (AP and axillary lateral to confirm component position, assess reduction, rule out fracture or dislocation), DVT prophylaxis (mechanical compression devices, early mobilization, consider pharmacologic if high risk but bleeding concerns with interscalene block). **Sling Immobilization**: 6 weeks for tendon peel or tenotomy repair, 4 weeks if secure lesser tuberosity osteotomy repair. Sling for comfort and protection - not strict immobilization. Remove for hygiene, exercises. Sleep in sling to prevent uncontrolled movement. **Rehabilitation Protocol - Strong Repair (LTO)**: - **Weeks 0-4**: Passive ROM only (pendulums 3-5 times daily, therapist-assisted elevation and ER to tolerance, pulley exercises), no active motion, no lifting - **Weeks 4-6**: Active-assisted ROM (continue passive program, add active-assisted with stick or pulley, gentle AAROM elevation and rotation) - **Weeks 6-12**: Active ROM (progress to active elevation, rotation, functional activities), gentle strengthening with resistance bands (progress from 0.5kg to 2kg resistance) - **Weeks 12-24**: Progressive strengthening (advance resistance, functional activities, return to swimming/golf 4-6 months), avoid heavy overhead lifting (greater than 25 pounds repetitive) **Rehabilitation Protocol - Standard Repair (Peel/Tenotomy)**: - **Weeks 0-6**: Passive ROM only (protect repair, no active IR), pendulums and therapist-assisted only - **Weeks 6-12**: Active-assisted ROM (gradual progression, monitor for apprehension or instability) - **Weeks 12-18**: Active ROM and gentle strengthening - **Weeks 18-24**: Progressive strengthening to functional levels **Follow-up Schedule**: 2 weeks (wound check, remove sutures/staples if used), 6 weeks (radiographs, assess healing, progress therapy), 12 weeks (radiographs, assess ROM and strength), 6 months, 1 year, then annually (monitor for loosening, component position, late complications). **Activity Restrictions**: No heavy overhead lifting (greater than 25 pounds repetitive) lifelong (component longevity concern), low-impact activities encouraged (swimming, golf, cycling), high-impact activities discouraged (contact sports, heavy labor), return to driving when off narcotics and can control vehicle (typically 6-8 weeks). **Radiographic Follow-up**: Baseline postoperative radiographs (AP, axillary lateral), 6 weeks (assess component position, early loosening signs), 3 months, 6 months, 1 year, then annually. Monitor for: radiolucent lines (greater than 2mm or progressive concerning for loosening), component migration or subsidence, periprosthetic osteolysis, heterotopic ossification, component wear. ## References 1. Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). Hip, Knee & Shoulder Arthroplasty: 2023 Annual Report. Adelaide: AOA; 2023. Available from: https://aoanjrr.sahmri.com/annual-reports-2023 2. Miller BS, Joseph TA, Noonan TJ, Horan MP, Hawkins RJ. Rupture of the subscapularis tendon after shoulder arthroplasty: diagnosis, treatment, and outcome. J Shoulder Elbow Surg. 2005;14(5):492-496. doi:10.1016/j.jse.2005.02.013 3. Walch G, Badet R, Boulahia A, Khoury A. Morphologic study of the glenoid in primary glenohumeral osteoarthritis. J Arthroplasty. 1999;14(6):756-760. doi:10.1016/s0883-5403(99)90232-2 4. Iannotti JP, Norris TR. Influence of preoperative factors on outcome of shoulder arthroplasty for glenohumeral osteoarthritis. J Bone Joint Surg Am. 2003;85(2):251-258. doi:10.2106/00004623-200302000-00011 5. Boileau P, Avidor C, Krishnan SG, Walch G, Kempf JF, Mole D. Cemented polyethylene versus uncemented metal-backed glenoid components in total shoulder arthroplasty: a prospective, double-blind, randomized study. J Shoulder Elbow Surg. 2002;11(4):351-359. doi:10.1067/mse.2002.125807 6. Edwards TB, Kadakia NR, Boulahia A, et al. A comparison of hemiarthroplasty and total shoulder arthroplasty in the treatment of primary glenohumeral osteoarthritis: results of a multicenter study. J Shoulder Elbow Surg. 2003;12(3):207-213. doi:10.1016/s1058-2746(02)86804-5 7. Sanchez-Sotelo J, Sperling JW, Rowland CM, Cofield RH. Instability after shoulder arthroplasty: results of surgical treatment. J Bone Joint Surg Am. 2003;85(4):622-631. doi:10.2106/00004623-200304000-00005 8. Terrier A, Reist A, Vogel A, Farron A. Effect of supraspinatus deficiency on humerus translation and glenohumeral contact force during abduction. Clin Biomech. 2007;22(6):645-651. doi:10.1016/j.clinbiomech.2007.01.015 9. Matsen FA 3rd, Clinton J, Lynch J, Bertelsen A, Richardson ML. Glenoid component failure in total shoulder arthroplasty. J Bone Joint Surg Am. 2008;90(4):885-896. doi:10.2106/JBJS.G.01263 10. Lazarus MD, Jensen KL, Southworth C, Matsen FA 3rd. The radiographic evaluation of keeled and pegged glenoid component insertion. J Bone Joint Surg Am. 2002;84(7):1174-1182. doi:10.2106/00004623-200207000-00013

Anatomic Total Shoulder Arthroplasty

Anatomic Total Shoulder Arthroplasty