import { OnePagerSummary, ExamWarning, InfoCardGrid, InfoCard, MnemonicCard, EvidenceCard, VivaScenarioSection, VivaScenario, ExamCheatSheet, ContentSection, ExamPearl, SafetyAlert, NumberHighlightRow, NumberHighlight, Tabs, Tab, ComparisonTable } from '@/components/mdx' **Location**: Exits quadrangular space 5-7cm below acromion, travels with posterior circumflex humeral artery **At Risk**: Fracture injury (5-10%), retractor placement, during tuberosity reduction **Protection**: Document preop function, gentle retractors, stay anterior during exposure **Location**: Enters conjoint tendon 5-8cm distal to coracoid tip (variable 3-10cm) **At Risk**: Aggressive medial retraction, dissection along conjoint **Protection**: Gentle retractors on conjoint, avoid vigorous medial pull, palpate nerve entry **Location**: Lies in deltopectoral interval, variable course **At Risk**: Often disrupted by fracture hematoma, can be divided if necessary **Protection**: Take laterally with deltoid or medially with pectoralis - avoid injury if preserving **Location**: Ascending branch travels along lateral bicipital groove to supply humeral head **At Risk**: Usually disrupted in fracture (causes AVN), further injury during dissection **Protection**: Identify and ligate if bleeding, avoid excessive stripping of proximal humerus **Location**: Bicipital groove between tuberosities - KEY VERSION LANDMARK **At Risk**: Avulsion from tuberosity fragments, can be used as tissue marker **Protection**: Preserve if intact for version reference, tag for identification, consider tenotomy if damaged **Patient Position**: Beach chair position at 60-80° (typically 70°), head secured in horseshoe headrest, bump/bolster under medial scapular border to position glenoid vertically, arm draped completely free including hand. Fluoroscopy C-arm available from contralateral side. Fracture table NOT needed. Mayo stand over chest for instruments. **Surgical Approach**: Deltopectoral approach - TRUE INTERNERVOUS PLANE (between deltoid [axillary nerve] and pectoralis major [medial and lateral pectoral nerves]). Fracture hematoma often disrupts normal planes but facilitates dissection. **Incision**: 15-18cm extensile incision from clavicle/AC joint extending distally past deltoid insertion onto arm - significantly longer than elective arthroplasty (which is 10-12cm) to access widely displaced fracture fragments and allow extensive soft tissue repair work. **Anesthesia**: General anesthesia with interscalene block for postoperative analgesia. Avoid indwelling catheters (phrenic nerve palsy risk). ## Indications for Hemiarthroplasty **Traditional Indications** (now evolving): - 3-part or 4-part proximal humerus fractures in elderly patients >70-75 years - Head-splitting fractures (>40% articular surface involvement or severe impaction) - Fracture-dislocation with valgus impacted head and predicted high AVN risk - Failed ORIF with humeral head collapse or AVN - Impression fractures >40% of articular surface (large Hill-Sachs or reverse Hill-Sachs) **Modern Evolution**: RSA (Reverse Shoulder Arthroplasty) now increasingly preferred over hemiarthroplasty for acute fractures in elderly patients because: - Better functional outcomes (mean forward elevation 120-130° vs 90-100° for hemi) - NOT dependent on tuberosity healing (RSA function preserved even with tuberosity nonunion) - Lower revision rates (5-10% vs 15-20% for hemi at 5 years) - More predictable pain relief **Hemiarthroplasty Still Considered For**: - Younger patients 65-75 years with reconstructable tuberosities and good bone quality - Patients with intact or reparable rotator cuff function - Anatomic reconstruction preferred by patient/surgeon - Contraindications to RSA (active deltoid dysfunction, infection concern) ## Neer Classification (Historical but Still Used) **1-Part**: All fragments displaced <1cm or angulated <45° - NONOPERATIVE treatment **2-Part**: One fragment displaced >1cm or angulated >45°: - Surgical neck (most common 2-part) - Greater tuberosity (second most common) - ORIF if displaced >5mm - Lesser tuberosity (rare) - Anatomic neck (rare, high AVN risk) **3-Part**: Two fragments displaced (third fragment is head): - Greater tuberosity + surgical neck (most common 3-part) - Lesser tuberosity + surgical neck (less common) - AVN risk 15-25% **4-Part**: All three fragments (GT, LT, shaft) displaced from head: - Head completely free, no soft tissue/vascular attachment - AVN risk 75-90% - Classic indication for arthroplasty vs RSA ## Preoperative Planning **Imaging Review**: - AP in scapular plane, Scapular Y, Axillary lateral X-rays - CT scan with 3D reconstruction ESSENTIAL - defines fragment size, displacement, comminution, head involvement - Identify: GT fragment size/quality, LT fragment, shaft comminution, head split/impaction - Measure contralateral normal shoulder for reference (head size, height landmarks) **Patient Assessment**: - Age, functional demand, hand dominance - Bone quality assessment (DEXA if available, cortical thickness on CT) - Rotator cuff quality (chronic tears suggest RSA over hemi) - Medical optimization (diabetes control, smoking cessation, nutritional status) - **CRITICAL**: Document preoperative neurovascular exam, especially axillary nerve function **Implant Planning**: - Head size from CT measurements (typically 43-49mm) - Stem length - standard vs long (long stem if metaphyseal comminution extends >5cm) - Cemented vs uncemented (cemented preferred in fracture setting for immediate stability) - Have revision options available (longer stems, RSA conversion if needed) ## Deltopectoral Interval **Boundaries**: - Lateral: Deltoid muscle (axillary nerve C5-C6) - Medial: Pectoralis major (medial and lateral pectoral nerves C5-T1) - TRUE INTERNERVOUS PLANE - safest approach to shoulder **Contents**: - Cephalic vein (variable course, may be disrupted in fracture) - Deltoid branch of thoracoacromial artery (superior) - In fracture cases: Extensive hematoma, disrupted planes ## Proximal Humerus Bony Anatomy **Greater Tuberosity** (posterolateral): - Supraspinatus attachment (superior facet) - abduction 0-90° - Infraspinatus attachment (middle facet) - external rotation - Teres minor attachment (inferior facet) - external rotation - Most commonly displaced fragment in fractures (pulled posterosuperiorly by rotator cuff) **Lesser Tuberosity** (anteromedial): - Subscapularis attachment (entire medial surface) - internal rotation, anterior stability - Displaced medially in fractures **Bicipital Groove**: - Between GT and LT - Contains long head biceps tendon (version landmark) - Anatomic retroversion 30-40° (aim 20-30° in prosthesis) **Surgical Neck**: - Metaphyseal region, weak area prone to fracture - Often comminuted in elderly osteoporotic bone ## Neurovascular Anatomy **Axillary Nerve**: - Terminal branch of posterior cord (C5-C6) - Exits quadrangular space with posterior circumflex humeral artery - Runs 5-7cm below acromion (variable, measure from bony landmarks) - Innervates deltoid and teres minor - **5-10% injured at presentation** in proximal humerus fractures - MUST document preoperatively **Musculocutaneous Nerve**: - Terminal branch of lateral cord (C5-C7) - Enters conjoint tendon (coracobrachialis) 5-8cm distal to coracoid (highly variable 3-10cm) - At risk with aggressive medial retraction - Innervates biceps, brachialis, coracobrachialis **Blood Supply to Humeral Head**: - **Anterior circumflex humeral artery** (branch of axillary artery): - Ascending branch travels in lateral bicipital groove - Enters head via arcuate artery - PRIMARY blood supply to head (>70%) - Usually disrupted in 3-part and 4-part fractures → AVN - **Posterior circumflex humeral artery**: Travels with axillary nerve, minor contribution - Head in 4-part fractures has NO soft tissue attachment → 90% AVN risk ## Step 1: Patient Positioning & Preoperative Planning Patient Positioning & Preoperative Planning: Beach chair at 70°. Bump under scapula. Entire arm free. Review CT scan and 3D reconstruction preoperatively to understand fracture pattern (Neer 3-part vs 4-part), fragment displacement, head involvement. Document axillary nerve function preoperatively (unable to assess if unconscious - document limitation). Mark fragments on skin using fluoroscopy. Plan tuberosity reduction strategy. Have RSA implants available as backup if tuberosities non-reconstructable. **Technical Tip**: EXAM KEY: 'I position the patient in beach chair with the arm completely free. Before draping, I review the CT scan carefully to understand the fracture pattern and plan my approach. I document axillary nerve function preoperatively - this is critical medicolegally as 5-10% of proximal humerus fractures have axillary nerve injury at presentation. I use fluoroscopy to mark the greater tuberosity fragment on the skin. I ensure RSA implants are available as a backup in case I encounter non-reconstructable tuberosities intraoperatively.' - Not documenting preoperative nerve status - medicolegal issues if postop deficit - Not reviewing imaging - miss fracture pattern complexity, inadequate implant planning - Inadequate positioning - difficult exposure, C-arm positioning issues - No RSA backup available - cannot convert if needed ## Step 2: Extensile Deltopectoral Incision Extensile Deltopectoral Incision: 15-18cm incision from AC joint/clavicle extending distally past deltoid insertion (significantly longer than elective arthroplasty 10-12cm). Deepen through subcutaneous tissue. Identify cephalic vein in deltopectoral interval - often disrupted by fracture hematoma, may ligate if necessary. Develop deltopectoral interval taking cephalic vein laterally with deltoid or medially with pectoralis. Evacuate fracture hematoma systematically. Explore full extent of fracture. Identify fragments by muscle attachments: GT (supraspinatus/infraspinatus), LT (subscapularis), shaft. **Technical Tip**: EXAM KEY: 'I make a generous incision, 15-18cm long, from the AC joint extending distally past the deltoid insertion. This is longer than elective arthroplasty because I need to access widely displaced fracture fragments and perform extensive soft tissue repair. I develop the deltopectoral interval - the cephalic vein is often disrupted by hematoma so I may need to ligate it. I evacuate the fracture hematoma systematically. I identify fragments by their soft tissue attachments - the greater tuberosity has supraspinatus and infraspinatus, the lesser tuberosity has subscapularis attached.' - Incision too short - inadequate fragment access, difficult tuberosity reduction - Not identifying all fragments early - poor reconstruction planning - Aggressive stripping of soft tissue from fragments - devascularization, nonunion risk - Injury to musculocutaneous nerve with medial retraction ## Step 3: Identify & Tag All Fracture Fragments Identify & Tag All Fracture Fragments: **CRITICAL STEP**: Identify and TAG all fragments before removing anything. **GREATER TUBEROSITY**: Contains supraspinatus (superior facet), infraspinatus (middle facet), teres minor (inferior facet). Often displaced posterosuperiorly by muscle pull. Place heavy non-absorbable suture (Ethibond #2 or #5) through tendon substance as TAG - minimum 2 sutures. **LESSER TUBEROSITY**: Contains subscapularis. Displaced medially. Tag with 2 heavy sutures. **HUMERAL HEAD**: Often free floating in 4-part fractures. Preserve for bone graft - DO NOT DISCARD. **SHAFT**: Identify and protect. Tag biceps tendon if intact (version landmark). Document fragment sizes, quality, comminution. **Technical Tip**: EXAM KEY: 'The most critical step is identifying and tagging all fracture fragments before proceeding. I place heavy non-absorbable sutures through the tuberosities with their cuff attachments - I use at least 2 sutures per tuberosity. The greater tuberosity has supraspinatus, infraspinatus, and teres minor - this is essential for abduction and external rotation. The lesser tuberosity has subscapularis - essential for internal rotation and anterior stability. I tag the long head of biceps if intact as this marks the bicipital groove which is my version reference point. In 4-part fractures, the head is often completely free without soft tissue - I carefully preserve this for bone graft later. I assess fragment quality - severe comminution or osteoporosis may indicate conversion to RSA.' - Not tagging fragments early - fragments lost in operative field, cannot reconstruct - Stripping soft tissue from tuberosities during tagging - devascularization, nonunion - Discarding head fragment prematurely - lose valuable autograft bone - Not identifying bicipital groove - version errors during stem implantation - Missing severe comminution - proceed with hemi when should convert to RSA ## Step 4: Remove Humeral Head & Assess Fragments Remove Humeral Head & Assess Fragments: Remove humeral head fragment (usually free/mobile in 3-part and 4-part). **DO NOT DISCARD** - set aside on back table for autograft bone. Assess head for: (1) AVN signs (dark, purple, no bleeding from bone) - expected in 4-part. (2) Size measurement with sizing template - typically 43-49mm diameter. (3) Articular cartilage integrity and head shape. Clear fracture site of small fragments and hematoma. Identify bicipital groove on shaft (if visible) or on head fragment (for version reference). Measure head diameter carefully. Assess tuberosity fragment quality, size, comminution, bone quality. Determine if reduction and stable fixation possible - if severely comminuted/osteoporotic, consider conversion to RSA. **Technical Tip**: EXAM KEY: 'I remove the humeral head fragment and carefully preserve it for autograft bone - this is critical for tuberosity healing. I assess it for signs of AVN and measure its size to select the appropriate prosthetic head diameter, typically 43-49mm. I identify the bicipital groove which is my key landmark for version - the normal humeral retroversion is 30-40 degrees, and I aim for 20-30 degrees in the prosthesis. I carefully assess the tuberosity fragments - their quality determines the functional outcome and whether I should proceed with hemiarthroplasty or convert to RSA. If tuberosities are severely comminuted or bone quality is very poor (severe osteoporosis), I have a low threshold to convert to RSA which has better outcomes and is not dependent on tuberosity healing.' - Discarding head fragment - lose autograft bone for tuberosity-shaft junction - Not measuring head size - wrong prosthesis diameter selection - Loss of bicipital groove reference - version errors (excessive retroversion or anteversion) - Not assessing fragment quality realistically - proceed with doomed reconstruction - Missing indication for RSA conversion - commit to inferior procedure ## Step 5: Prepare Humeral Canal Prepare Humeral Canal: Identify humeral shaft. Clear soft tissue from proximal 3-4cm of shaft exposing metaphyseal bone. **CRITICAL**: Use bicipital groove as version reference (normal anatomic retroversion 30-40°). Goal is 20-30° retroversion in prosthesis. Open canal with box chisel or curved awl starting in **CENTER of metaphysis** (NOT lateral - causes varus stem position). Sequential reaming/broaching to cortical contact. In fracture cases, metaphyseal bone is often weak/comminuted - extend stem into diaphysis for stability. May need longer stem (standard 80-100mm or long 150mm+) for adequate fixation. Cemented fixation strongly preferred in fracture setting due to weak bone and need for immediate stability. **Technical Tip**: EXAM KEY: 'I prepare the humeral canal using the bicipital groove as my version reference. I aim for 20-30 degrees of retroversion in the prosthesis - slightly less than the normal anatomic 30-40 degrees. In fracture cases, the metaphyseal bone is often weak and comminuted, so I typically use a longer stem extending 5-7cm into the diaphysis for stability, and I use cemented fixation for immediate stability to allow early passive motion. I start the canal in the center of the metaphysis to avoid varus stem alignment. The starting point is critical - too lateral causes varus malalignment which leads to superior migration and glenoid erosion. I sequentially broach until I achieve cortical contact, feeling the rasp engage strong diaphyseal bone.' - Starting point too lateral - varus stem position, superior migration, glenoid erosion, poor outcomes - Excessive retroversion >35° - loss of internal rotation, limits function - Excessive anteversion <15° - posterior instability risk - Short stem in severely comminuted metaphysis - early loosening, subsidence - Iatrogenic humeral shaft fracture during preparation - need longer stem or cerclage - Uncemented fixation in osteoporotic bone - micromotion, loosening ## Step 6: Determine Prosthetic Height & Head Size Determine Prosthetic Height & Head Size: **MOST CRITICAL DECISION**: Prosthetic height determines tuberosity tension and healing. Goal: RESTORE NORMAL ANATOMY. Use anatomic landmarks: **(1) Superior edge of pectoralis major insertion is 5.5-6cm distal to top of head - GOLD STANDARD landmark**. (2) Distance from top of head to greater tuberosity typically 8-10mm. (3) Measure from native head if available. (4) Use contralateral shoulder radiograph for reference. Insert trial stem to planned depth. Place trial head. Assess: Tuberosities should reduce to anatomic position **WITHOUT TENSION** when head is on. If too high = excessive tension on tuberosity reduction, leads to nonunion and stiffness. If too low = instability, superior migration, cuff dysfunction. Head size from native head measurement (typically 43-49mm, most common 45-47mm). **Technical Tip**: EXAM KEY: 'Determining prosthetic height is one of the most critical and difficult decisions in fracture hemiarthroplasty - it determines whether tuberosities will heal. I use multiple references: The superior edge of the pectoralis major insertion is 5-6cm distal to the top of the head - this is my primary landmark. The greater tuberosity sits 8-10mm below the top of the head. I measure the native head if available and I use the contralateral shoulder X-ray for reference. During trialing, the tuberosities must reduce to their anatomic position without tension - if there is tension the prosthesis is too high and I need to seat it deeper or use a shorter head offset. The most common error is placing the prosthesis too high which causes tuberosity nonunion and stiffness. It is better to err slightly low than high. I verify height by attempting passive forward elevation to 90-100° during trialing - if there is excessive resistance, the prosthesis is too high.' - Prosthesis too HIGH - stiffness, tuberosity under tension, nonunion (MOST COMMON ERROR - 40% of failures) - Prosthesis too LOW - instability, superior migration, cuff dysfunction, glenoid erosion - Wrong head size - overstuffing (stiffness) or understuffing (instability, eccentric loading) - Not using contralateral shoulder for reference - no anatomic baseline - Not trialing before cementing - cannot adjust height after cementation ## Step 7: Trial Reduction of Tuberosities Trial Reduction of Tuberosities: **Before cementing final stem**, perform comprehensive trial reduction to confirm height and plan fixation. Using tagged sutures, reduce greater tuberosity to posterior-superior position on prosthetic head. Should sit ~8-10mm below top of head in anatomic position. Reduce lesser tuberosity to anterior position on prosthesis, medial to bicipital groove. Hold tuberosities with tagged sutures. Assess: (1) **NO TENSION on reduction** - fragments should reduce easily. (2) Adequate bone-to-bone contact with shaft and prosthesis. (3) Ability to secure with sutures/cerclage - assess fixation points. (4) Closure of rotator interval between GT and LT. If tuberosities don't reduce easily or spring away, **prosthesis is likely too HIGH - must revise height before cementing**. Check passive ROM with tuberosities held - should achieve 90-100° elevation, 20-30° ER without excessive tension. **Technical Tip**: EXAM KEY: 'Before cementing the final stem, I perform a comprehensive trial reduction of the tuberosities. I reduce the greater tuberosity to the posterior-superior aspect and the lesser tuberosity anteriorly using the tagged sutures. They should reduce easily without tension and sit stably against the prosthesis and shaft. If there is tension or they spring away from the prosthesis, the prosthetic height is too high and I must revise it - this is why trialing is critical. Once the stem is cemented, height cannot be easily adjusted. I check passive range of motion with the tuberosities held - I should achieve 90-100 degrees of forward elevation without excessive tension. I assess the fixation points and plan my suture technique - identifying where I will place vertical mattress sutures through the shaft, horizontal cerclage sutures, and side-to-side sutures. This trial step prevents the most common technical error.' - Cementing stem before trialing tuberosities - cannot adjust height, committed to wrong height - Accepting tension on tuberosity reduction - leads to 40% nonunion rate and poor outcomes - Not checking ROM during trial - miss stiffness/impingement until too late - Proceeding despite poor tuberosity contact - setup for nonunion - Not planning suture fixation strategy - disorganized fixation, weak construct ## Step 8: Cement Final Humeral Stem Cement Final Humeral Stem: After satisfactory trial with tuberosity reduction, prepare for final cementation. Remove trial components and irrigate canal. Prepare cement (PMMA - high-viscosity with antibiotic, typically gentamicin or vancomycin). Dry canal with gauze or suction. Optional: Use distal cement restrictor (placed 1-2cm below planned stem tip). Pressurize cement into humeral canal with finger packing, then cement gun or syringe for distal canal. Insert final stem in correct **VERSION** (20-30° retroversion using bicipital groove reference) and **HEIGHT** (determined from trialing with pectoralis major landmark). Hold stem in position with steady axial pressure until cement sets (~8-10 minutes for high-viscosity cement). Avoid mallet strikes on stem (can fracture cement). Ensure stem fully seated to planned depth using proximal landmark (pectoralis insertion). Remove excess cement before complete polymerization. **Do NOT assemble head yet** - need access to fix tuberosities first. **Technical Tip**: EXAM KEY: 'I cement the final humeral stem after satisfactory trialing. I use antibiotic-loaded high-viscosity cement - typically gentamicin 1-2g per batch - and I pressurize it into the canal for a good cement mantle, which improves fixation and reduces infection risk. I insert the stem at 20-30 degrees of retroversion using the bicipital groove as my reference landmark, and at the precise height I determined during trialing using the pectoralis major insertion as my guide. I hold it steady with axial pressure until the cement fully polymerizes - usually 8-10 minutes. I never strike the stem with a mallet as this can fracture the cement mantle. I do NOT place the final head yet because I need access to fix the tuberosities first - the head goes on last after all tuberosity sutures are placed. I verify the stem is fully seated to the planned depth by checking the relationship to the pectoralis major insertion.' - Wrong version - functional limitation (excessive retroversion → loss of IR, excessive anteversion → instability) - Wrong height - cannot correct after cementation, leads to tuberosity failure or instability - Cement extrusion into soft tissues - heterotopic ossification, stiffness, neurovascular injury - Stem not fully seated - changes height, proud stem prevents tuberosity reduction - Placing head before tuberosity fixation - very difficult to work around head, poor fixation - Mallet strike on assembled components - cement fracture, loss of fixation ## Step 9: Bone Graft Tuberosity-Shaft Junction Bone Graft Tuberosity-Shaft Junction: **CRITICAL FOR HEALING**: Use preserved humeral head as autograft source. Morselized head into small cancellous bone chips using rongeur, bone mill, or rasp. Pack bone graft generously at tuberosity-shaft junction circumferentially. Place graft between tuberosities (GT and LT). Fill metaphyseal void. Creates biological environment for union - studies show bone graft improves tuberosity healing from 60% without graft to 80-85% with graft. The metaphyseal void is often large (2-4cm) in comminuted 4-part fractures - fill completely. Some surgeons place graft under tuberosities as well for additional contact. Place graft before reducing and fixing tuberosities. **Technical Tip**: EXAM KEY: 'I use the native humeral head as autograft bone, morselizing it into cancellous chips using a rongeur or bone mill. I pack this generously at the tuberosity-shaft junction circumferentially and between the tuberosities. This is critical for healing - evidence shows bone graft significantly improves tuberosity union rates from 60% without graft to 80-85% with graft. The metaphyseal void in comminuted 4-part fractures can be quite large, and the autograft provides both mechanical scaffold and biological stimulus for healing. I use all available head bone - typically 20-30cc of graft. I place the graft before reducing the tuberosities so it is compressed when I fix the tuberosities down onto the shaft.' - Not using bone graft - 40% lower tuberosity healing rates, poor outcomes - Discarding head fragment early - no autograft source available - Inadequate graft packing - insufficient biological scaffold - Using allograft when autograft available - inferior healing ## Step 10: Reduce & Fix Greater Tuberosity Reduce & Fix Greater Tuberosity: **MOST IMPORTANT fragment for function**. Reduce greater tuberosity (with supraspinatus, infraspinatus, teres minor attached) to ANATOMIC position: posterior-superior humeral head/prosthesis, sitting ~8-10mm below top of prosthetic head. Hold with previously placed tagged sutures. Fix to SHAFT with heavy non-absorbable sutures (#2 or #5 Ethibond) using multiple techniques: **(1) Vertical mattress sutures** through drill holes in shaft (2-3 sutures). **(2) Horizontal cerclage sutures** around shaft and through tuberosity tendon (2 sutures). **(3) Side-to-side sutures** to lesser tuberosity closing rotator interval (2 sutures). **(4) Sutures through prosthesis holes** if available (1-2 sutures). **Minimum 6-8 sutures total** for GT. Ensure bone-to-bone contact of GT to shaft compressing autograft. Test fixation - should be STABLE without gapping with gentle traction. No sharp edges of bone that could cut sutures. **Technical Tip**: EXAM KEY: 'The greater tuberosity is the most important fragment to fix because it contains the posterior-superior rotator cuff which is essential for abduction and external rotation - if it doesn't heal, the patient has a very poor outcome with pseudoparalysis. I reduce it anatomically to sit 8-10mm below the prosthetic head top and fix it with multiple heavy non-absorbable sutures in a comprehensive construct. I use at least three different fixation points: First, I pass 2-3 vertical mattress sutures through drill holes in the shaft from lateral to medial. Second, I place 2 horizontal cerclage sutures around the shaft capturing the GT tendon. Third, I place 2 side-to-side sutures to the lesser tuberosity which closes the rotator interval. If the prosthesis has suture holes, I use those as a fourth point. I typically use 6-8 sutures total for the GT. The fixation must be stable enough to allow early passive motion at 1-2 weeks. I ensure there is direct bone-to-bone contact of the GT to the shaft which compresses the autograft we placed. I test the fixation with gentle traction - there should be no gapping.' - Inadequate fixation - tuberosity migration, nonunion (occurs in 30-40% historically, devastating) - Anatomic malposition - persistent dysfunction even if healed - Too superior position - subacromial impingement, pain, limited elevation - Too inferior position - loss of lever arm, poor mechanics - Weak sutures (#0 or smaller) or too few sutures (<4) - fixation failure - Sharp bone edges - suture cutting, late failure - No bone-to-bone contact - relying on suture fixation alone, nonunion ## Step 11: Reduce & Fix Lesser Tuberosity Reduce & Fix Lesser Tuberosity: Reduce lesser tuberosity (with subscapularis attached) to ANTERIOR position on prosthesis. Anatomic position: medial to bicipital groove, on anterior metaphysis. Hold with previously placed tagged sutures. Fix to SHAFT with heavy non-absorbable sutures using multiple techniques: **(1) Vertical mattress sutures** through drill holes in shaft (2 sutures). **(2) Side-to-side sutures** to greater tuberosity - **CRITICAL** to close rotator interval completely with no gap (2-3 sutures). **(3) Horizontal cerclage** if needed for additional stability (1 suture). **(4) To prosthesis holes** if available (1 suture). **Minimum 4-6 sutures total** for LT. Ensure **NO GAP between GT and LT** - closes rotator interval, improves stability, prevents superior migration. Ensure bone-to-bone contact LT to shaft. Test fixation stability with gentle traction - no gapping. **Technical Tip**: EXAM KEY: 'I reduce the lesser tuberosity with subscapularis attached to the anterior prosthesis, medial to the bicipital groove in its anatomic position. I fix it with a similar heavy suture technique using 4-6 sutures total. I use vertical mattress sutures through bone tunnels in the shaft, and most importantly I place 2-3 side-to-side sutures to the greater tuberosity. This is critical because closing the gap between GT and LT - closing the rotator interval - provides additional stability and prevents superior migration of the prosthesis. The lesser tuberosity provides internal rotation function and anterior stability. I ensure there is bone-to-bone contact of the LT to the shaft. If the LT fragment is small or comminuted, I may incorporate it into the subscapularis repair and advance the subscapularis directly to the prosthesis and shaft. I test the fixation with gentle traction - there should be no gapping with shoulder in neutral or external rotation.' - Gap between tuberosities - rotator interval defect, superior migration, instability, poor outcomes - Malposition of LT - loss of internal rotation, anterior instability - Inadequate fixation - LT nonunion, subscapularis failure - Excessive tension on subscapularis - tendon failure, stiffness - Not incorporating comminuted LT - fragment lost, subscapularis dysfunction ## Step 12: Place Final Prosthetic Head Place Final Prosthetic Head: After tuberosity fixation complete and stable with all sutures tied, place final prosthetic head. Choose head size based on native head measurement from Step 4 (typically 43-49mm diameter, most common 45-47mm). Choose head HEIGHT/offset to restore anatomy while maintaining tuberosity reduction - typically standard height/offset. Snap or screw head onto humeral stem taper (mechanism depends on system). Verify secure seating with gentle traction test. **Do NOT strike head with mallet** (can damage taper morse lock or cause cement fracture). Check that tuberosities remain well-positioned with head in place. May need to adjust tuberosity sutures around head for optimal position. Rotate head to best position for tuberosity coverage. **Technical Tip**: EXAM KEY: 'After I have completed all the tuberosity fixation and tied all sutures, I place the final prosthetic head. I choose the size based on the native head measurement I made earlier, typically 43-49mm in diameter with 45-47mm being most common. I select the standard head height in most cases to restore anatomy while maintaining the tuberosity position we achieved. I seat the head onto the taper with firm hand pressure - I never strike it with a mallet as this can damage the taper morse lock or cause cement fracture which would be catastrophic requiring stem removal. I verify the head is fully seated by attempting to lift it off the taper - it should be locked. I verify the tuberosities remain well-positioned with the head in place and rotate the head to the position that provides best tuberosity coverage and stability. In some systems the head can be rotated on the taper to optimize position.' - Wrong head size - overstuffing (stiffness, glenoid erosion) or understuffing (instability, eccentric wear) - Mallet strike on assembled head - taper damage, morse lock failure, cement fracture - Displacing tuberosities while placing head - requires re-fixing - Head not fully seated on taper - dissociation risk, instability - Wrong head height/offset - changes construct stability and tuberosity tension ## Step 13: Final Stability Assessment & ROM Final Stability Assessment & ROM: Reduce shoulder and assess stability systematically in all directions: **(1) ANTERIOR stability**: Extend arm and externally rotate - assesses subscapularis/LT repair, should be stable. **(2) INFERIOR stability**: Axial traction - should be minimal translation, tests tuberosity fixation and prosthetic height. **(3) POSTERIOR stability**: Forward flex to 90° and internally rotate - should be stable. **(4) SUPERIOR**: Assess for superior subluxation. Check PASSIVE ROM (do not force): Forward elevation to 90-120° (limited intentionally to protect tuberosity healing). External rotation to 20-40°. Internal rotation limited. Assess tuberosity fixation throughout ROM - should remain stable without gapping or crepitus. If gapping occurs, fixation inadequate - requires revision. Document maximum passive ROM achieved for postoperative protocol planning. **Technical Tip**: EXAM KEY: 'I perform systematic stability testing in all directions. I test anterior stability by extending the arm and externally rotating to assess the lesser tuberosity and subscapularis repair - it should be stable. I test inferior stability with axial traction - there should be minimal translation. I test posterior stability with forward flexion and internal rotation. Then I check passive range of motion carefully - I should achieve 90-120 degrees of forward elevation but I do not force it beyond what feels safe for the tuberosity fixation. External rotation to 20-40 degrees is typical. Throughout the range of motion, I continuously assess the tuberosity fixation - I should feel smooth motion without any gapping or crepitus. If I feel the tuberosities gapping or hear crepitus, the fixation is inadequate and I need to revise it with additional sutures. This intraoperative ROM assessment guides my postoperative rehabilitation protocol - if the fixation feels very strong, I can be more aggressive with passive motion. If it feels tenuous, I protect longer.' - Forcing ROM beyond safe limits - tuberosity fixation failure intraoperatively - Not testing stability systematically - miss instability pattern until postoperatively - Not documenting maximum safe ROM - medicolegal issues, inability to guide rehabilitation - Accepting unstable tuberosity fixation - guaranteed failure, requires revision - Not assessing throughout arc - may be stable at 0° but gap at 90° flexion ## Step 14: Closure & Immobilization Closure & Immobilization: Copious irrigation (minimum 9L pulsatile lavage, 3L per 3L bag). Meticulous hemostasis with electrocautery - fracture surgery has more bleeding. Place deep suction drain (10mm flat drain) deep to deltoid. Close rotator interval between supraspinatus and subscapularis if any defect remains (usually partially closed by tuberosity repair). May place additional reinforcing sutures in cuff if tissue quality poor. Close deltopectoral interval loosely with 2-3 absorbable sutures (2-0 Vicryl) - **do not restrict deltoid excursion**. Subcutaneous layer with 2-0 Vicryl. Skin closure with subcuticular 3-0 Monocryl or staples. Sterile dressing. **IMMOBILIZE in shoulder sling with ABDUCTION PILLOW at 30° abduction** - this is critical to offload tuberosities and protect repair. Some surgeons use neutral rotation vs slight external rotation. Document postoperative neurovascular exam especially axillary nerve (deltoid contraction, sensation over lateral shoulder). **Technical Tip**: EXAM KEY: 'I achieve meticulous hemostasis and irrigate copiously with at least 9 liters of pulsatile lavage. I place a deep suction drain which I will remove at 24-48 hours when drainage decreases below 30cc per 8 hours. I close the deltopectoral interval loosely with just 2-3 sutures to avoid restricting the deltoid muscle. I immobilize in a sling with an abduction pillow at 30 degrees of abduction - this is critical because it offloads tension on the tuberosities and protects the repair during the critical 6-week healing period. The abduction pillow is not optional - it is a key component of success. I document a careful postoperative neurovascular examination especially the axillary nerve which I documented preoperatively. I test deltoid contraction and sensation over the lateral shoulder. I obtain immediate postoperative X-rays to confirm component position and tuberosity reduction before the patient leaves the operating room.' - Inadequate hemostasis - hematoma formation increases stiffness and infection risk - Overtight deltopectoral closure - restricts deltoid excursion, contributes to stiffness - No abduction pillow - excessive tension on tuberosities during healing, high nonunion rate - Not documenting postoperative neuro exam - medicolegal issues if deficit develops - Drain too superficial - inadequate drainage, hematoma - Sling in adduction - tension on GT repair, higher failure rate ## Step 15: Postoperative X-rays & Planning Postoperative X-rays & Planning: Obtain immediate postoperative X-rays before leaving OR: AP in scapular plane, scapular Y, axillary lateral (or Velpeau axillary if cannot position arm). Assess systematically: **(1) Prosthetic head size and height** - should restore anatomy, GT sitting 8-10mm below head. **(2) Tuberosity position** - GT posterior-superior, LT anterior, no gap between them, anatomic contact with shaft. **(3) Stem alignment** - neutral, not varus (varus predicts superior migration). **(4) Version** - difficult to assess on X-ray but stem should appear centered. **(5) No fracture extension** to shaft. **(6) Cement mantle quality** if visible. Document X-ray findings in operative note. Plan individualized rehabilitation protocol based on: Tuberosity fixation quality (strong vs tenuous), bone quality (normal vs osteoporotic), patient factors (compliance, age). If fixation strong and bone good, standard protocol (passive 0-6 weeks). If fixation tenuous or bone osteoporotic, extended protection (passive 0-8 weeks, delayed active 8-12 weeks). Communicate directly with physiotherapist regarding ROM restrictions. **Technical Tip**: EXAM KEY: 'I obtain three postoperative X-ray views immediately in the operating room: AP in scapular plane, scapular Y, and axillary lateral if possible or Velpeau axillary view if the arm cannot be positioned. I systematically assess the X-rays: The prosthetic height and head size should restore anatomy, with the greater tuberosity sitting 8-10mm below the prosthetic head top. The tuberosity positions should be anatomic - GT posterior-superior, LT anterior, with no gap between them visible on axillary view. The stem alignment should be neutral on AP view - varus alignment predicts superior migration and poor outcomes. I confirm there is no intraoperative fracture extension into the shaft. These X-rays serve as the critical baseline for all follow-up comparisons. I plan the rehabilitation protocol based on the quality of tuberosity fixation I achieved - if the fixation is strong and bone quality is good, I use the standard protocol with passive motion 0-6 weeks then active 6-12 weeks. If fixation is tenuous or bone is severely osteoporotic, I extend the protection period to 8-12 weeks before allowing active motion. I communicate directly with the physiotherapist about ROM restrictions and my assessment of fixation quality.' - Not obtaining immediate postop X-rays - miss malposition or fracture until too late - Not assessing X-rays systematically - miss subtle varus alignment or tuberosity malposition - Wrong rehabilitation protocol - tuberosity failure (too aggressive) or stiffness (too conservative) - Starting aggressive active therapy too early - tuberosity nonunion (30-40% if too early) - Not communicating with therapist - protocol not followed, complications - No baseline X-rays - cannot assess tuberosity healing or migration at follow-up ## Additional Complications **Heterotopic Ossification (10-20%)** - Usually mild, rarely limits function - Prevention: Consider indomethacin 25mg TDS for 6 weeks in high-risk patients (head trauma, burns, HO history) - Treatment: Observe if asymptomatic, excision if severe limitation after maturity (12-18 months) **Glenoid Erosion (20-30% long-term)** - Especially with superior migration, rotator cuff dysfunction - Eccentric loading of glenoid - May require conversion to TSA or RSA if symptomatic - Difficult surgery with bone grafting often needed **Nerve Injuries (Other)** - Musculocutaneous (rare <1%): Avoid aggressive medial retraction - Suprascapular (very rare): Avoid superior dissection - Radial (rare): Positioning injury, padding - Ulnar (rare): Positioning injury, padding ## Immobilization (Critical for Tuberosity Healing) **Weeks 0-6**: Sling with **abduction pillow at 30° abduction** (NOT adduction) at all times except for exercises and hygiene - Abduction pillow offloads tension on GT repair (reduces pull of supraspinatus) - Sleep in sling with pillow (elevated position, recliner often helpful) - Remove only for gentle passive exercises and dressing - **NO active motion, NO lifting, NO weight bearing** **Weeks 6-8**: Wean from abduction pillow based on X-ray evidence of tuberosity healing - May transition to simple sling for additional 2 weeks if healing progressing - Continue night immobilization longer if bone quality poor or fixation tenuous ## Physiotherapy Protocol **Phase 1 (Weeks 0-6): Passive ROM Only - TUBEROSITY PROTECTION PRIORITY** Restrictions: NO active motion, NO active-assisted motion, NO lifting - Pendulum exercises (gravity-assisted): 3-5 minutes, 3-4 times daily starting Day 1-2 postop - Passive forward elevation (therapist or opposite arm): Goal 90° by week 4, 120° by week 6 - Passive external rotation in scapular plane: Goal 20° by week 4, 30° by week 6 - NO internal rotation stretching (protects subscapularis/LT) - Elbow, wrist, hand active ROM to prevent stiffness **Phase 2 (Weeks 6-8): Active-Assisted ROM** Prerequisites: X-ray evidence of tuberosity healing (callus formation, no migration) - Active-assisted forward elevation with cane/pulley: Progress from 90° to 140° - Active-assisted external rotation: Progress to 40-45° - Begin gentle internal rotation (hand to stomach) - Gentle scapular exercises (clock exercises on wall) - Continue passive ROM to maintain gains - Still NO active lifting or resistance **Phase 3 (Weeks 8-12): Active ROM** Prerequisites: Progressive tuberosity healing on X-ray, no pain with active-assisted - Begin active forward elevation without support: Progress to 120-140° - Active external rotation and internal rotation - Supine active elevation (gravity-eliminated position first) - Progress to upright active motion - Begin very gentle isometric strengthening (no resistance) **Phase 4 (Weeks 12-16): Gentle Strengthening** Prerequisites: Radiographic tuberosity union (cortical bridging on 3 of 4 cortices) - Progressive resistance exercises with theraband - Light weights (0.5-1kg maximum) for deltoid and rotator cuff - Functional exercises (reaching, lifting light objects) - Continue ROM maintenance **Phase 5 (Months 4-6): Functional Strengthening** - Progressive resistance increase (up to 2-3kg) - Functional activities and ADLs - Sport/activity-specific training if appropriate (limited for most fracture patients) - Plateau by 6-12 months ## Follow-up Schedule **2 weeks**: Wound check, drain removal (if still in), verify patient performing passive ROM correctly **6 weeks**: X-ray (AP, scapular Y, axillary) to assess tuberosity healing, advance to active-assisted if healing **12 weeks**: X-ray to confirm progressive healing, advance to strengthening if healed **6 months**: X-ray to assess final tuberosity position and union, component position, glenoid **1 year**: X-ray and functional assessment **2 years and annually**: X-ray to monitor for late complications (loosening, glenoid erosion, HO) ## Expected Functional Outcomes **IF TUBEROSITIES HEAL** (60-80% with bone graft and good fixation): - Forward elevation: 100-130° (compare to 160-170° normal) - External rotation: 30-45° - Internal rotation: Limited, to buttock or sacrum - Pain: Minimal to none - Function: ADLs achievable, limited overhead work - Satisfaction: 70-80% satisfied **IF TUBEROSITIES DO NOT HEAL** (20-40%): - Forward elevation: 60-90° (pseudoparalysis) - External rotation: <20° - Pain: Moderate to severe - Function: Severely limited, difficulty with ADLs - Satisfaction: <40% satisfied - Often requires conversion to RSA **Compare to RSA for acute fractures** (growing evidence): - Forward elevation: 120-140° (BETTER, not dependent on tuberosity healing) - External rotation: 20-30° (similar or slightly worse) - Pain relief: Superior to hemiarthroplasty - Satisfaction: 85-90% (BETTER) ## Red Flags Requiring Urgent Review - Sudden loss of function (tuberosity failure) - Increasing pain after initial improvement (infection, loosening) - Wound drainage, erythema (infection) - New neurological deficit (nerve injury) - Visible deformity (dislocation, fracture) ## References 1. Boileau P, Krishnan SG, Tinsi L, et al. Tuberosity malposition and migration: reasons for poor outcomes after hemiarthroplasty for displaced fractures of the proximal humerus. J Shoulder Elbow Surg. 2002;11(5):401-412. 2. Bufquin T, Hersan A, Hubert L, Massin P. Reverse shoulder arthroplasty for the treatment of three- and four-part fractures of the proximal humerus in the elderly: a prospective review of 43 cases with a short-term follow-up. J Bone Joint Surg Br. 2007;89(4):516-520. 3. Gallinet D, Clappaz P, Garbuio P, et al. Three or four parts complex proximal humerus fractures: hemiarthroplasty versus reverse prosthesis: a multicenter, randomized, controlled study. Orthop Traumatol Surg Res. 2009;95(7):493-498. 4. Greiner S, Kaab MJ, Haas NP, Bail HJ. Humeral head necrosis rate after fracture treatment with hemiarthroplasty. Orthopedics. 2008;31(11):1073-1077. 5. Krishnan SG, Reineck JR, Bennion PD, et al. Shoulder arthroplasty for fracture: does a fracture-specific stem make a difference? Clin Orthop Relat Res. 2011;469(12):3317-3323. 6. Mata-Fink A, Meinke M, Jones C, et al. Reverse shoulder arthroplasty for treatment of proximal humeral fractures in older adults: a systematic review. J Shoulder Elbow Surg. 2013;22(12):1737-1748. 7. Neer CS 2nd. Displaced proximal humeral fractures. I. Classification and evaluation. J Bone Joint Surg Am. 1970;52(6):1077-1089. 8. Robinson CM, Page RS, Hill RM, et al. Primary hemiarthroplasty for treatment of proximal humeral fractures. J Bone Joint Surg Am. 2003;85(7):1215-1223. 9. Sebastiá-Forcada E, Cebrián-Gómez R, Lizaur-Utrilla A, Gil-Guillén V. Reverse shoulder arthroplasty versus hemiarthroplasty for acute proximal humeral fractures. A blinded, randomized, controlled, prospective study. J Shoulder Elbow Surg. 2014;23(10):1419-1426. 10. Spross C, Platz A, Rufibach K, et al. The PHILOS plate for proximal humeral fractures--risk factors for complications at one year. J Trauma Acute Care Surg. 2012;72(3):783-792.

Shoulder Hemiarthroplasty for Acute Proximal Humerus Fracture

Shoulder Hemiarthroplasty for Acute Proximal Humerus Fracture