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 5-7cm inferior to lateral acromion, travels around surgical neck **Protection**: Stay superior during inferior capsular release, palpate nerve before inferior screw insertion, limit retraction **Location**: Enters coracobrachialis muscle 3-8cm distal to coracoid tip, lateral to conjoined tendon **Protection**: Avoid aggressive lateral retraction, identify before subscapularis release, protect during humeral exposure **Location**: Medial to coracoid, deep to pectoralis minor, typically 2-3cm from deltopectoral interval **Protection**: Gentle medial retraction only, avoid deep medial dissection, recognize if inadvertent exposure occurs **Location**: Superficial in deltopectoral fat, proximal and distal branches crossing interval **Protection**: Careful subcutaneous dissection, preserve cephalic vein branches, avoid excessive cautery superficially **Location**: Pass through suprascapular notch posteriorly, 2-3cm from glenoid rim, at risk with posterior baseplate screws **Protection**: Limit posterior-superior screw trajectory to 20mm depth, angle screws away from notch, use drill guides ## Imaging Assessment ### CT Scan Analysis (Essential) **High-yield**: 3D CT reconstruction mandatory for revision cases - assess glenoid bone stock, version, wear patterns, screw trajectories, and plan bone grafting needs. **Key measurements on CT:** - Glenoid bone loss volume (Favard classification: E0-E4) - Anterior-posterior dimension (minimum 20mm for standard baseplate) - Superior-inferior height (minimum 25mm) - Version (excessive retroversion necessitates correction) - Scapular anatomy for screw planning **Favard Classification of Glenoid Bone Loss:** - **E0**: Intact bone stock - **E1**: Centered erosion, minor defect - **E2**: Superior defect, biconcave pattern - **E3**: Superior + posterior defect, >25mm loss - **E4**: Severe global bone loss, <50% intact ### Radiographic Evaluation **AP and axillary views assess:** - Component loosening (radiolucent lines, component migration) - Tuberosity position and healing - Humeral bone stock and cortical integrity - Acromion morphology and prior fracture - Heterotopic ossification extent ### Previous Operative Reports **Critical information:** - Original implant manufacturer and model (order extraction instruments) - Fixation method (cemented vs press-fit) - Complications during index procedure - Soft tissue state (subscapularis repair, cuff integrity) - Obtain manufacturer-specific extraction tools for humeral component - Have bone graft available (allograft femoral head or distal tibia) - Arrange longer operative time (90-150 minutes typical) - Extended revision instrumentation set (extended stems, augments, bone graft screws) - Cross-match blood products (revision carries higher bleeding risk) ## Patient Assessment **Indications for revision to reverse:** - Failed anatomic TSA with irreparable rotator cuff tear - Failed hemiarthroplasty with pain and dysfunction - Severe glenoid component loosening with bone loss - Proximal humerus fracture sequelae (tuberosity nonunion, malunion) - Recurrent instability not amenable to revision anatomic TSA **Relative contraindications:** - Active infection (requires two-stage with spacer) - Severe glenoid bone loss without grafting option (E4 with <40% stock) - Deltoid dysfunction or axillary nerve palsy - Neuropathic arthropathy - Medical comorbidities prohibiting major surgery ## Patient Positioning ### Beach Chair Position **Setup specifics:** - Back support 30-45° from horizontal - Head secured in padded headrest, neutral rotation - Operative shoulder positioned at edge of table - Entire upper extremity and hemithorax prepped - Arm freely mobile in all planes **Technical tip**: Position patient far lateral on table so operative shoulder sits at table edge - this allows full extension and adduction access during humeral preparation without table obstruction. **Padding and pressure points:** - Bony prominences padded (sacrum, heels, contralateral elbow) - Kidney rest support to prevent shifting - Sequential compression devices for DVT prophylaxis ### Draping Technique **Steps:** - U-drape around shoulder - Stockinette to mid-humerus - Isolation drape to separate head from field - Ensure superior access to acromion - Lateral access for arm manipulation ## Extended Deltopectoral Approach ### Incision - Mark coracoid process - Palpate deltopectoral interval (cephalic vein guides) - Incision from coracoid to deltoid insertion (12-15cm) - May need to extend distally for humeral component removal **Incision details:** - Start 2cm lateral to coracoid tip - Extend inferiorly along deltopectoral interval - Distal extent to mid-humeral shaft if needed for stem removal - Can extend proximally toward clavicle if needed for exposure ### Interval Development **Layer-by-layer:** 1. **Subcutaneous dissection** - Identify and preserve lateral cutaneous nerves when possible - Minimize cautery to reduce wound complications - Develop flaps to visualize cephalic vein 2. **Cephalic vein identification** - Usually lies on deltoid side of interval - Retract laterally with deltoid (preferred) or ligate if needed - Preserve deltoid perforating branches 3. **Deltopectoral interval** - Blunt dissection between deltoid (lateral) and pectoralis major (medial) - Release clavipectoral fascia - Identify and protect musculocutaneous nerve entering coracobrachialis **Exam key**: In revision cases, the deltopectoral interval may be obliterated by scarring - stay superficial initially, identify cephalic vein first, then work deep to interval plane using blunt technique. 4. **Deltoid retraction** - Place self-retaining retractor (Kolbel, Fukuda) - Gentle lateral retraction on deltoid - Avoid aggressive lateral traction (risk to axillary nerve) 5. **Superior and inferior exposure** - Release superior 1-2cm of pectoralis major insertion if needed - Inferior capsular release carefully (axillary nerve protection) - Tag residual subscapularis if present ## Assessment of Components ### Humeral Component **Determine fixation type from operative note:** - Cemented: requires cement removal after stem extraction - Press-fit: may have significant bony ingrowth - Modular vs monoblock design **Check for complications:** - Periprosthetic fracture (intraoperative management needed) - Component dissociation - Polyethylene wear debris - Tuberosity status ### Glenoid Component (if present) **Assess:** - Loosening extent (probe periphery) - Bone loss pattern (central, peripheral, eccentric) - Polyethylene wear - Screw removal needs ## Humeral Component Removal ### Soft Tissue Releases If subscapularis present and intact: - Perform lesser tuberosity osteotomy (preferred for healing) OR - Direct tendon peel (mark tissue for repair) - Tag with heavy braided suture - Protect throughout case for final repair **Capsular releases:** - Release anterior capsule from humeral neck - Careful inferior release (axillary nerve 5-7cm from acromion) - Posterior release as needed for exposure - Preserve tissue for later repair when possible ### Cemented Stem Removal **Technique:** 1. **Expose cement-bone interface** - Remove any accessible cement superiorly - Define proximal extent of cement mantle - Osteotome between cement and bone 2. **Create extraction purchase** - Slot-cutting burr along anterior stem - Create sufficient access for extraction tools - Avoid aggressive force causing fracture 3. **Extract stem** - Use manufacturer-specific extraction device if available - Impact extraction through slap hammer - Alternative: Gigli saw around cement mantle - Progressive small taps rather than large impacts **Technical pearl**: If cemented stem proves difficult, consider extended humeral osteotomy - create anterior cortical window with oscillating saw, preserve bone bridge distally, extract stem, reconstruct osteotomy with cables/cerclage. 4. **Cement removal** - Hand instruments (curved osteotomes, curettes) - Ultrasonic cement removal system (Sontec) - Preserve cortical bone stock - Remove all cement to achieve bleeding bone bed ### Uncemented Stem Removal **Well-fixed stems:** - May require extended humeral osteotomy - Plan osteotomy location (proximal third typically) - Use oscillating saw for precise cuts - Maintain distal bone bridge for stability - Mark osteotomy edges for anatomic reduction **Osteotomy technique:** 1. Plan anterior longitudinal osteotomy (8-10cm) 2. Preserve lateral and posterior cortex continuity 3. Create bone window to access stem 4. Extract stem through window 5. Preserve osteotomy fragment for repair **Loose stems:** - Mobilize with curved osteotomes - Twist and extract - Minimal bone loss with this scenario ## Glenoid Component Removal ### Polyethylene Insert Removal **Steps:** - Identify locking mechanism - Use manufacturer-specific removal tool - Lever out polyethylene insert - Inspect metal baseplate/keel ### Metal-Backed Component Removal Goal: Remove component while preserving maximum glenoid bone stock for reverse baseplate fixation **Technique:** 1. **Remove screws first** - Identify screw heads - Use appropriate driver - Remove systematically - Note any stripped/broken screws 2. **Mobilize baseplate** - Thin curved osteotome at bone-implant interface - Work circumferentially around periphery - Gentle levering action - Avoid plunging into glenoid vault 3. **Keeled component** - May need to drill around keel - Use high-speed burr to create troughs alongside keel - Extract with steady pull - Preserve bone between drill troughs ### All-Polyethylene Component Removal **Steps:** - Score around component with saw - Use curved gouges to mobilize - Remove any bone cement - Ream to healthy bleeding bone ### Assess Final Bone Stock **Critical measurement:** - Anterior-posterior diameter (minimum 20mm needed) - Superior-inferior height (minimum 25mm) - Central depth available for central peg - Peripheral bone for screw purchase **If inadequate bone stock** → proceed to bone grafting (see below) ## Glenoid Bone Grafting (if needed) ### Indications **Structural bone graft needed when:** - Favard E2-E4 defects - Anterior-posterior diameter less than 20mm - Superior bone loss preventing baseplate rim contact - Contained central cavitary defect greater than 10mm deep ### Graft Options **Structural allograft (femoral head or distal tibia):** - Shape to match defect contour - Fix with 3.5mm or 4.0mm screws - Ream flat surface for baseplate seating - Baseplate screws engage native and graft bone **Bone substitute alternatives:** - Cancellous chips for small contained defects - Impaction grafting for central deficiency - Avoid in large structural defects **Exam key**: BIO-RSA (bone-increased offset reverse) developed for superior glenoid bone loss - uses augmented baseplate with metallic wedge to restore anatomy without bone grafting. Preserves joint line and version correction. ## Baseplate Preparation ### Glenoid Exposure **Steps:** - Complete capsular release - Place retractors (Fukuda, Darrach) - Anterior, posterior, superior, inferior visualization - Remove labrum and soft tissue - Identify glenoid rim completely ### Reaming **Technique:** 1. **Initial reaming** - Use spherical reamer matching planned baseplate - Ream to bleeding bone (viable bed) - Progressive reamer sizes if needed - Goal: flat, well-prepared surface 2. **Version correction** - Excessive retroversion common in revision - Ream anterior more than posterior to correct - Goal: neutral to 5° retroversion 3. **Assess rim contact** - Trial baseplate should contact entire periphery - No gaps at rim (risk for loosening) - Reream if poor contact ### Central Peg Preparation Central peg provides 30-40% of baseplate fixation strength - ensure excellent fit and depth **Steps:** - Locate center of glenoid face (usually just inferior to center) - Use central drill guide - Drill to appropriate depth (25-30mm typical) - Ream peg hole to match baseplate peg diameter - Should have firm rotational stability ## Baseplate Positioning and Fixation ### Baseplate Orientation **Inferior tilt 10-15° (critical):** - Reduces scapular notching (polyethylene impingement on inferior scapula) - Optimizes impingement-free motion arc - Use guide to set angle - Confirm with trial before final impaction **Version:** - Neutral to 5° retroversion optimal - Excessive anteversion risks anterior instability - Excessive retroversion limits external rotation **High-yield concept**: Inferior baseplate tilt and proper lateralization creates optimal biomechanics - increases deltoid moment arm, reduces shear forces at glenoid-baseplate interface, minimizes scapular notching. ### Screw Insertion **Principles:** - Minimum 4 screws (some systems allow 6) - Divergent trajectories for maximal purchase - Bicortical purchase ideal - Avoid suprascapular nerve posteriorly **Standard screw placement:** 1. **Superior screw** (anterior-superior quadrant) - Angled toward base of coracoid - Usually longest screw (30-40mm) - Avoids suprascapular notch 2. **Anterior-inferior screw** - Angled toward glenoid pillar - Typically 20-30mm 3. **Posterior-superior screw** - Limit to 20mm depth - Angle away from suprascapular notch - Most dangerous screw trajectory 4. **Posterior-inferior screw** - Aimed toward lateral scapular border - 25-35mm typically - Posterior-superior screw: suprascapular nerve 2-3cm from rim at notch - Anterior screws: avoid medial perforation into thorax (pneumothorax risk) - Inferior screws: axillary nerve 5-7cm inferior to acromion - Always use drill guides and depth control ### Baseplate Impaction **Technique:** - Final baseplate positioning - Central peg fully seated - Peripheral rim complete contact - Impactor with sequential taps - Check stability (no rocking) - Insert locking screws per design ## Humeral Component ### Preparation **Humeral canal:** - Remove residual cement completely - Ream canal to bleeding bone - Progressive broaches to size - May need revision-length stem if bone loss **Version setting:** - 0-20° retroversion typical - Reference posterior humeral cut or epicondyles - Less retroversion than anatomic TSA - Check with trial to ensure no impingement ### Humeral Component Insertion **Cemented technique (common in revision):** - Clean and dry canal - Cement restrictor if needed - Retrograde cementing - Pressurize cement - Insert stem in correct version - Hold until cement sets - Remove excess cement **Press-fit technique:** - Appropriate stem diameter for canal - Progressive broaching - Final stem size should have rotational stability - Insert with impactor - Check final version ### Modular Components **Reverse humeral components:** - Modular poly liner (various thicknesses) - Select size based on trial reduction - Goal: appropriate tension without overstuffing **Avoid overstuffing**: Excessive joint tension risks scapular notching, stiffness, and acromial stress fracture. Trial should allow smooth motion without excessive resistance. ## Trial Reduction ### Assessment **Check systematically:** 1. **Stability** - Range humeral component through full motion - No dislocation tendency - Stable at extremes of motion 2. **Tension** - Moderate resistance to distraction - Not overly tight or loose - Compare to contralateral if available 3. **Motion** - Impingement-free elevation - Internal and external rotation smooth - No scapular notching with adduction 4. **Liner thickness** - May need to upsize or downsize - Affects joint tension directly - Thicker = more tension ### Final Implant Insertion **Steps:** - Remove trial components - Insert final humeral liner onto baseplate ball - Ensure proper locking mechanism engaged - Reduce humeral component onto ball - Confirm stability in neutral position ## Soft Tissue Repair ### Subscapularis Reconstruction (if possible) **High-yield**: Subscapularis repair in reverse TSA controversial - not anatomically functional but may provide anterior stability and improved internal rotation. **Lesser tuberosity osteotomy repair:** - Reduce tuberosity fragment to anatomic position - Fix with heavy braided suture through drill holes - Alternative: suture anchors or cable/wire fixation - Repair to lesser tuberosity and anterior capsule **Tendon peel repair:** - Repair tagged subscapularis to tissue at lesser tuberosity - Use heavy braided suture - Side-to-side closure if possible ### Capsular Closure **Anterior capsule:** - Repair capsule if adequate tissue - Reinforces stability - Closes dead space ## Wound Closure **Layer-by-layer:** 1. **Deep layer** - Close deltopectoral interval partially if desired - Re-approximate clavipectoral fascia - Absorbable suture (0 or 2-0 Vicryl) 2. **Subcutaneous layer** - Eliminate dead space - 2-0 or 3-0 absorbable suture - Avoid excessive tension 3. **Skin** - Running subcuticular (Monocryl or similar) - Interrupted nylon acceptable - Skin adhesive or sterile strips **Dressing:** - Sterile dressing - Shoulder immobilizer - Ice therapy ## Postoperative Protocol ### Immediate (0-6 weeks) **Week 0-2:** - Sling immobilization except exercises - Passive forward elevation to 90° (therapist only) - Passive external rotation to 30° in scapular plane - Active elbow, wrist, hand exercises - Wound check at 2 weeks **Week 2-6:** - Continue sling - Progress passive motion to 140° elevation, 45° ER - Gentle pendulum exercises - No active elevation yet (deltoid must heal to function) NO active shoulder elevation until 6 weeks minimum - violating this risks deltoid detachment and loss of function ### Intermediate (6-12 weeks) **Week 6:** - Wean from sling - Begin active-assisted elevation - Progressive active elevation as able - Continue passive stretching - Gentle isometric strengthening **Week 8-12:** - Active motion emphasized - Strengthening program initiated - Functional activities as tolerated - Most patients achieve 120-130° elevation ### Advanced (3-6 months) **Month 3-6:** - Progressive resistance exercises - Sport/work-specific training - Expect continued improvement to 1 year - Final motion typically: 120-140° elevation, 30-40° ER ### Expected Outcomes **Pain relief:** - 85-90% significant improvement - VAS reduction 6-7 points typical **Function:** - ASES score improvement 35-45 points - ROM: 120-140° elevation average - External rotation limited (30-40° typical) **Return to activities:** - Light activities: 3 months - Full activities: 6 months - Continued improvement: up to 12-18 months ## Complications Management ## References 1. Boileau P, Watkinson DJ, Hatzidakis AM, Balg F. Grammont reverse prosthesis: design, rationale, and biomechanics. J Shoulder Elbow Surg. 2005;14(1 Suppl S):147S-161S. doi:10.1016/j.jse.2004.10.006 2. Favard L, Levigne C, Nerot C, Gerber C, De Wilde L, Mole D. Reverse prostheses in arthropathies with cuff tear: are survivorship and function maintained over time? Clin Orthop Relat Res. 2011;469(9):2469-2475. doi:10.1007/s11999-011-1833-y 3. Walch G, Mottier F, Wall B, Boileau P, Mole D, Favard L. Acromial insufficiency in reverse shoulder arthroplasties. J Shoulder Elbow Surg. 2009;18(3):495-502. doi:10.1016/j.jse.2008.12.002 4. Sanchez-Sotelo J, Wagner ER, Sim FH, Houdek MT. Allograft-prosthetic composite reconstruction for massive proximal humeral bone loss in reverse shoulder arthroplasty. J Bone Joint Surg Am. 2017;99(24):2069-2076. doi:10.2106/JBJS.17.00237 5. Klein SM, Dunning P, Mulieri P, Pupello D, Downes K, Frankle MA. Prosthetic glenoid component position in reverse shoulder arthroplasty. J Shoulder Elbow Surg. 2011;20(5):761-766. doi:10.1016/j.jse.2010.08.024 6. Levigne C, Boileau P, Favard L, et al. Scapular notching in reverse shoulder arthroplasty. J Shoulder Elbow Surg. 2008;17(6):925-935. doi:10.1016/j.jse.2008.02.010 7. Groh GI, Heckman MM, Wirth MA, Curtis RJ, Rockwood CA Jr. Treatment of glenoid deficiency in revision shoulder arthroplasty with a structural bone graft. J Shoulder Elbow Surg. 2008;17(1):60-67. doi:10.1016/j.jse.2007.03.022 8. Stephenson DR, Oh JH, McGarry MH, Rick Hatch GF III, Lee TQ. Effect of humeral component version on impingement in reverse total shoulder arthroplasty. J Shoulder Elbow Surg. 2011;20(4):652-658. doi:10.1016/j.jse.2010.08.020 9. Zumstein MA, Pinedo M, Old J, Boileau P. Problems, complications, reoperations, and revisions in reverse total shoulder arthroplasty: a systematic review. J Shoulder Elbow Surg. 2011;20(1):146-157. doi:10.1016/j.jse.2010.08.001 10. Melis B, DeFranco M, Ladermann A, et al. An evaluation of the radiological changes around the Grammont reverse geometry shoulder arthroplasty after eight to 12 years. J Bone Joint Surg Br. 2011;93(9):1240-1246. doi:10.1302/0301-620X.93B9.25926

Revision Shoulder Arthroplasty to Reverse

Revision Shoulder Arthroplasty to Reverse