import { OnePagerSummary, ExamWarning, InfoCardGrid, InfoCard, MnemonicCard, EvidenceCard, VivaScenarioSection, VivaScenario, ExamCheatSheet, ContentSection, ExamPearl, SafetyAlert, NumberHighlightRow, NumberHighlight, Tabs, Tab, ComparisonTable } from '@/components/mdx' **Temporal Classification of Post-TKA Stiffness** | Timing | Definition | Preferred Treatment | |--------|------------|---------------------| | Early | Less than 6-12 weeks | MUA (optimal window) | | Intermediate | 3-6 months | Arthroscopic or open lysis | | Late | Greater than 6 months | Open arthrolysis ± revision | **Stiffness Pattern Classification** | Pattern | Definition | Primary Cause | |---------|------------|---------------| | Flexion deficit | Flexion less than 90° | Anterior adhesions, tight posterior capsule | | Extension deficit | FCE greater than 10° | Posterior adhesions, inadequate bone cuts | | Global stiffness | Both deficits | Arthrofibrosis, infection, CRPS | **Functional ROM Requirements** - Level walking: 67° flexion - Stair climbing: 83° flexion - Rising from chair: 93° flexion - Tying shoes: 105° flexion **Patient Factors** - Pre-operative stiffness (strongest predictor) - Complex Regional Pain Syndrome (CRPS) - Poor compliance with physiotherapy - Low pain tolerance - Diabetes, inflammatory arthritis **Surgical Factors** - Component malposition (especially femoral internal rotation greater than 3°) - Femoral component oversizing (blocks flexion) - Tibial component oversizing/malposition - Patella baja or maltracking - Inadequate posterior osteophyte removal - Residual PCL in PS design **Post-operative Factors** - Infection (must exclude in all cases) - Haematoma/haemarthrosis - Prolonged immobilisation - Inadequate analgesia limiting rehabilitation - Heterotopic ossification **Step 1: Exclude Infection** - ESR, CRP, white cell count - Knee aspiration: WBC greater than 1,100/μL, PMN greater than 64% - Alpha-defensin if equivocal **Step 2: Imaging Assessment** - Plain radiographs: Component position, sizing, loosening - CT rotation study: Femoral rotation relative to TEA (greater than 3° IR = malposition) - Lateral radiograph: Patella height (Insall-Salvati 0.8-1.2) **Step 3: Treatment Selection** | Presentation | No Component Issue | Component Issue | |--------------|-------------------|-----------------| | Early (less than 12 weeks) | MUA | MUA first, revise if fails | | Intermediate (3-6 months) | Arthroscopic/Open lysis | Revision with lysis | | Late (greater than 6 months) | Open arthrolysis | Revision TKA | **Step 4: Postoperative Optimisation** - Continuous passive motion (CPM) - Regional anaesthesia (indwelling femoral catheter or adductor canal block) - Aggressive physiotherapy - Consider anti-inflammatory prophylaxis **For MUA** - General or spinal anaesthesia (full relaxation essential) - Fluoroscopy (optional - assess for fracture if excessive force) - Leg holder (if available) **For Arthroscopic Lysis** - Standard knee arthroscopy set - Arthroscopic shaver and radiofrequency device - Anterolateral and anteromedial portals - Superomedial/superolateral portals for suprapatellar pouch **For Open Arthrolysis** - Standard TKA instrument set - Full revision instruments available - Polyethylene insert exchange options - Constrained liner available - Quadriceps snip/V-Y turndown instruments (if needed) - TTO equipment (if needed for severe cases) **Lies 3-5mm posterior to posterior capsule in flexion** - At extreme risk during posterior capsule release for flexion contracture. Injury may not be immediately apparent (intimal tear). EXAM KEY: Use elevator on posterior tibia, release capsule from bone with knee flexed 90°, never use sharp dissection posteriorly. **Wraps around fibular neck 2-3cm distal to joint line** - At risk with aggressive lateral release or valgus correction. EXAM KEY: If lateral retraction needed, protect with finger, avoid retractors at fibular neck level, check peroneal function immediately post-op. **Insertion may be compromised, especially in revision/stiff knee** - Avulsion occurs at tibial tubercle insertion during MUA or exposure. Risk factors: patella baja, previous surgery. EXAM KEY: If resistance during MUA, STOP - consider open approach. Intraoperatively, maintain 45° flexion during exposure. **Quadriceps tendon and patellar insertion vulnerable in stiff knees** - May rupture with aggressive manipulation or excessive force during exposure. EXAM KEY: If cannot evert patella, use lateral parapatellar approach, quadriceps snip, or rectus snip. Never force eversion. **MCL especially vulnerable with aggressive valgus manipulation or medial release** - Rupture converts primary procedure to constrained revision. EXAM KEY: Protect MCL during medial adhesion release, avoid valgus stress during MUA, check stability after lysis - may need increased constraint. **Sites of Adhesion Formation** | Location | Effect on ROM | Release Priority | |----------|--------------|------------------| | Suprapatellar pouch | Limits flexion | High | | Lateral gutter | Limits flexion and patellar mobility | Highest | | Medial gutter | Limits flexion | Moderate | | Posterior capsule | Limits extension | For FCE only | | Patellofemoral articulation | Limits flexion | Moderate | **Key Anatomical Measurements** - Patella-popliteal artery distance: 10-15mm (flexed), 30mm (extended) - Common peroneal nerve to fibular head: adherent - Joint line to fibular head: 15-20mm - Patellar tendon length: 45-55mm (Insall-Salvati ratio 0.8-1.2) **Mandatory Investigations** 1. **Infection Screen** - ESR (elevated greater than 30mm/hr suspicious) - CRP (elevated greater than 10mg/L suspicious) - Knee aspiration: WBC greater than 1,100/μL, PMN greater than 64% - Hold aspiration if on antibiotics (2-week washout) 2. **Imaging** - AP/lateral radiographs: Component position, sizing, loosening - Skyline view: Patellar tracking, thickness, position - CT rotation study: Femoral component rotation (should be 0-3° ER relative to TEA) - Component assessment: Posterior condylar offset, joint line height 3. **Component Analysis** - Femoral size: Oversizing blocks flexion (anterior impingement) - Tibial rotation: Should align with tibial tubercle - Patella position: Baja limits flexion, alta limits stability ### Step 1: Anaesthesia and Positioning Patient supine on standard operating table. General anaesthesia or spinal with complete motor block essential - any muscle guarding increases fracture risk. Tourniquet on thigh but NOT inflated. Fluoroscopy available. **Optimal Timing**: MUA most successful at 6-12 weeks post primary TKA. Success rate 85-90% in this window, drops to less than 50% after 3 months due to mature scar formation. After 6 months, MUA rarely successful - proceed to open lysis. ### Step 2: Baseline ROM Assessment Document pre-manipulation ROM under anaesthesia. Compare to recorded intraoperative ROM from primary surgery. Note any crepitus, instability, or malalignment. **Expected Intraoperative ROM Targets**: - Flexion: Greater than 120° (or within 10° of primary intraoperative) - Extension: Full (0°) ### Step 3: Flexion Manipulation Hold distal femur with one hand providing counter-pressure. Hold proximal tibia with other hand. Apply slow, progressive flexion force. Feel for sequential release of adhesions (popping sensation). Target minimum 120° flexion or audible/palpable scar release. - NEVER use rapid forceful manipulation - risk of fracture, tendon rupture - Apply force through TIBIA, not ankle (avoid ligament injury) - Maintain axial compression during flexion (reduces fracture risk) - If resistance at 90° with no release, STOP - consider fluoroscopy for occult fracture ### Step 4: Extension Manipulation For flexion contracture, extend knee fully with gentle sustained pressure. May need to hold for 60-90 seconds. Feel posterior capsule release. ### Step 5: Fluoroscopic Assessment If any concern for fracture (excessive force required, sudden loss of resistance), obtain fluoroscopic images in AP and lateral projections. ### Step 6: Post-Manipulation Assessment Document final ROM achieved. Check for any crepitus, instability, or haemarthrosis. Apply compression bandage. **MUA Contraindications**: Periprosthetic fracture, component loosening, infection, heterotopic ossification (Brooker III/IV), greater than 6 months post-surgery, previous extensor mechanism repair. ### Step 1: Positioning and Approach Patient supine with tourniquet. Use previous midline incision. Raise full-thickness skin flaps to expose fascia. Incise fascia and identify arthrotomy plane. **Approach Decision**: If concern about patellar eversion, consider lateral parapatellar approach rather than standard medial parapatellar. Allows direct access to lateral gutter adhesions and easier patella subluxation. ### Step 2: Arthrotomy with Extensile Options Begin medial parapatellar arthrotomy. If patella cannot be everted/subluxed, employ extensile measures in order: 1. **Quadriceps Snip**: 45° incision into vastus lateralis from proximal medial arthrotomy 2. **Rectus Snip**: Release rectus tendon from quadriceps tendon proximally 3. **V-Y Quadriceps Turndown**: Rarely needed for stiffness alone 4. **TTO**: Last resort - adds significant morbidity ### Step 3: Lateral Gutter Release Most common and important site of adhesions. Use sharp dissection to release fibrotic tissue from lateral femoral condyle, lateral tibial plateau, and lateral patella facet. Restore patellofemoral tracking. Lateral release should not extend below joint line. If needed distally, protect common peroneal nerve at fibular neck. ### Step 4: Suprapatellar Pouch Lysis Release adhesions in suprapatellar pouch. Essential to restore quadriceps excursion. Blunt finger dissection often sufficient. Ensure free gliding of quadriceps muscle. ### Step 5: Medial Gutter Release Release medial parapatellar adhesions. Be cautious of MCL insertion at femur and tibia. Less common site of restrictive adhesions than lateral side. ### Step 6: Posterior Capsule Release (if Extension Deficit) For flexion contracture greater than 10° that doesn't respond to anterior releases: 1. Flex knee 90° to move popliteal vessels posteriorly 2. Use curved elevator on posterior tibia 3. Release posterior capsule from tibia, staying on bone 4. Check extension - repeat if needed ALWAYS flex knee to 90° during posterior release. Use elevator on bone, not sharp dissection. If arterial bleeding occurs, apply pressure, extend knee, and call vascular surgery. ### Step 7: Component Assessment Assess for component malposition: - Femoral rotation: Internal rotation causes lateral patella tracking and stiffness - Femoral sizing: Oversizing causes anterior impingement in flexion - Tibial rotation: Should align with tibial tubercle - Posterior osteophytes: Remove any residual ### Step 8: Polyethylene Assessment and Exchange Consider insert exchange if: - Thickness contributing to overstuffing - Damage from manipulation or arthrofibrosis debris - Need for increased constraint after soft tissue releases ### Step 9: ROM Check and Closure Confirm greater than 120° flexion and full extension. Check patella tracking. Close in layers over drain. Compression bandage applied with knee in extension. **Immediate Post-operative** - Continuous Passive Motion (CPM): Start 0-90°, increase 10°/day as tolerated - Regional anaesthesia: Indwelling femoral catheter or adductor canal block for 48-72 hours - Cryotherapy and compression **Rehabilitation Protocol** - Day 1: CPM, isometric quadriceps, ankle pumps - Day 2-3: Weight-bearing as tolerated, active ROM exercises - Week 1-2: Target 90° flexion, full extension - Week 2-6: Progress to full ROM, strengthening - Week 6-12: Return to activities **Adjunctive Measures** - NSAIDs (indomethacin 25mg TDS) for heterotopic ossification prophylaxis - Consider low-dose radiation if high HO risk - Psychological support if CRPS suspected **Key to Maintaining ROM**: Pain control is paramount. Regional anaesthesia allows aggressive early rehabilitation without opioid-related sedation and nausea limiting participation. 1. Pfefferle KJ, Shemory ST, Tilbury RT, et al. Risk factors for manipulation after total knee arthroplasty: a pooled electronic health record database study. J Arthroplasty. 2014;29(10):2036-2038. 2. Scranton PE Jr. Management of knee pain and stiffness after total knee arthroplasty. J Arthroplasty. 2001;16(4):428-435. 3. Christensen CP, Crawford JJ, Olin MD, Vail TP. Revision of the stiff total knee arthroplasty. J Arthroplasty. 2002;17(4):409-415. 4. Nicholls DW, Dorr LD. Revision surgery for stiff total knee arthroplasty. J Arthroplasty. 1990;5(Suppl):S73-77. 5. Esler CN, Lock K, Harper WM, Gregg PJ. Manipulation of total knee replacements. Is the flexion gained retained? J Bone Joint Surg Br. 1999;81(1):27-29. 6. Kim J, Nelson CL, Lotke PA. Stiffness after total knee arthroplasty: prevalence of the complication and outcomes of revision. J Bone Joint Surg Am. 2004;86(7):1479-1484. 7. Yercan HS, Sugun TS, Bussiere C, et al. Stiffness after total knee arthroplasty: prevalence, management and outcomes. Knee. 2006;13(2):111-117. 8. Ghani H, Maffulli N, Khanduja V. Management of stiffness following total knee arthroplasty: a systematic review. Knee. 2012;19(6):751-759. 9. Mont MA, Serna FK, Krackow KA, Hungerford DS. Exploration of radiographically normal total knee replacements for unexplained pain. Clin Orthop Relat Res. 1996;331:216-220. 10. Australian Orthopaedic Association National Joint Replacement Registry. Annual Report 2023. Adelaide: AOA; 2023.

Management of Stiff Total Knee Arthroplasty

Management of Stiff Total Knee Arthroplasty