HTO Syllabus
2014-07-01
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6/30/2014 Clinica Ortopedica e Traumatologica Università degli Studi di Pavia Fondazione IRCCS Policlinico San Matteo Direttore: Prof. F. Benazzo Fixed Unicompartmental Knee Arthroplasty in Young Osteoarthritic Knee F. Benazzo, SMP Rossi, M. Ghiara Disclosure • • • • LimaCorporate Consultant, Conceptor Zimmer Consultant, Conceptor Ceramtec Consultant Fidia Consultant UNI and Young Patients Focus on • • • • Dilemmas Indications and contraindications Implant selection with specific indications Up-to-date indications (combined implants, ACL reconstruction, postrauma/osteotomy) • Return to sport 1 6/30/2014 Dilemmas 2012 - Surgeons, given identical information, do not concur on treatment for patients with the same pathology. - Decision making process heavily influenced by radiographic findings but individual surgeons are consistent with their own treatment choice. - Consensus treatment for medial osteoarthritis of the knee remains in question. Dilemmas - If a more standardised approach to offering this surgical care is to be achieved, then improved decision support for patients around this specific treatment choice will be required. - Comprehensive comparative data across the three treatment options (UKA;TKA;HTO) is not available. Dilemmas Uni vs TKR • preservation of bone stock and soft tissues, • more natural gait pattern and kinematics, • improved range of motion • reduced operative time • reduced incision size. 2 6/30/2014 Dilemmas Gait: No differences were noted between the groups (UKA or HTO) other than at 3 months after surgery when there was a significant difference in the timedistance variable of gait in favor of UKR. This became insignificant at 1-year and 5-year follow-up Borjesson M, Weidenhielm L, Mattsson E, Olsson E: Gait and clinical measurements in patients with knee osteoarthritis after surgery: a prospective 5year follow-up study. Knee 2005, 12:121-127 Indications Classic: • Unicompartmental degenerative disease (medial or lateral) with mild degeneration of the opposite side • Painful osteonecrosis/osteochondritic involvement of the femoral condyle, with or without rim narrowing 3 6/30/2014 Indications Classic: • Deformity of the anatomical axis of the limb due to narrowing of the joint line for the degenerative disease and not to deformity of the tibia (schuss x-rays view) • Deformity correctable manually (stress x-rays) and therefore surgically, with the thickness of the implant Indications Classic: • • • • • • • Healthy (functionally valid) ACL Full or almost full flexion (ROM almost normal) Finger sign positive Age > 60 years BMI < 30 Varus /valgus deformity < 10° Flexion contracture < 10° 4 6/30/2014 Indications Enlarged: • Age < 60 years • BMI >30 … < 32 • Presence of degenerative patello-femoral joint without anterior knee pain (no full-thickness chondral lesions or lateral facet involvement) Indications Enlarged: • ACL deficient knee frequent in young patients - low demanding patients tibial slope < 7° - Possibility of ACL reconstruction together with the UNI Indications ACL and Tibial slope: - >7° should be avoided - particularly if the anterior cruciate ligament is absent at the time of implantation. - An intact anterior cruciate ligament, even when partly degenerated, was associated with the maintenance of normal anteroposterior stability of the knee for an average of sixteen years following unicompartmental knee arthroplasty. Hernigou P, Deschamps G: Posterior slope of the tibial implant and the outcome of unicompartmental knee arthroplasty. J Bone Joint Surg Am 2004, 86:506-511 5 6/30/2014 Implant selection 1) Resurfacing 2) Measured resection Different philosophies Slightly different indications Choice is a matter of age Implant selection Resurfacing: - “la uni c’est du resurfaçage” by Philippe Cartier bone sparing and of respecting the joint physiology respect of the so called “Cartier angle”(angle of tibial varus deviation) Reaming of the cartilage surface on the femoral side. Implant selection Measured resection: - Implants and concepts that are closer to a total knee design and philosophy - Tibial cut at 90° and a parallel cut on the femoral side (based upon the tibial cut) 6 6/30/2014 Implant selection Indications Our experience : resurfacing in case of more degenerated OA with condylar recession Less bone to be removed Easier to avoid overcorrection Measured resection Resurfacing Measured resection Resurfacing Implant selection Fixed vs mobile - Good results with both implants - Different philosophies - Different techniques 7 6/30/2014 Implant selection Indications: • No specific indications according to each specific design Our opinion: • ACL concomitant reconstruction, partially deficient ACL: fixed bearing • Lateral OA: fixed bearing Surgical technique: medial Uni No matter the implant design • Tibial sagittal plane: slope = native, mostly 3°-5° • Tibial coronal plane: - 90° - Pristine varus (Cartier angle) • Osteophytes removal from tibia and femur: MCL release Surgical technique: medial Uni No matter the implant design • Femur: central /slightly lateral positioning of the femoral component on the condyle, avoiding notching with the tibial spine • Balancing: slight looseness to avoid lateral overloading (1-2 mm) 8 6/30/2014 Surgical technique: lateral Uni No matter the implant design • Femur: no osteophyte removal from femoral condyle. The osteophytic overgrowth can be used to support the femoral component particularly on hypoplastic condyles • The component must be implanted as lateral as possible • Some remaining valgus (no full correction) Up-to-date indications Uni solo: “one finger sign” + slight AKP with only medial facet involved Beard et al The influence of the presence and severity of pre-existing patellofemoral degenerative changes on the outcome of the Oxford medial unicompartmental knee replacement Pre-operative clinical and radiological assessment of the patellofemoral joint in unicompartmental knee replacement and its influence on outcome JBJS Br, 2007 . F. Benazzo, S. M. P. Rossi, L. Piovani, A. Combi, S. Perle Bi-uni und bi-uni + femoropatellarer Gelenkersatz 2012 Up-to-date indications 9 6/30/2014 Up-to-date indications Up-to-date indications Up-to-date indications Considerations • Uni insufficient to improve patellar tracking and provide pain relief if lateral facet involved • TKA is an overkilling solution: ACL sacrificed, lateral compartment sacrificed 10 6/30/2014 Up-to-date indications Uni and acl: technical issues • tunnel positioning • approach • stability of the implant 6 months 11 6/30/2014 Up-to-date indications Uni + ACL Trans-tibial approach Problems: • Tunnel widening • Possible secondary impingement with metal back • Possible tibial baseplate subsidence Up-to-date indications Our solution: Acl trans-am reconstruction • Tunnel widening: unavoidable • Prosthesis site placement: unchangeable • Transfer tibial tunnel from medial site closer to tt, producing an anatomic foot print Move away tunnel from prosthesis Reduce likelihood of impingement between new-ACL and baseplate Up-to-date indications 12 6/30/2014 Up-to-date indications 1 year Lateral UNI Lateral arthritis: 10% of patients with knee OA - Valgus knee - Post-traumatic - Post-osteotomy Lateral UNI 13 6/30/2014 Follow-up 3 months Lateral UNI Lateral UNI Lateral 3.UNI UNI 14 6/30/2014 Return to sport - More patients returned to or increased sports following UKA (P=.0003), but no sooner than TKA patients. - Patient-perceived Oxford and modified Grimby scores were better and sporting activity was greater following mini-incision UKA compared to TKA. Walton et al Patient-perceived outcomes and return to sport and work: TKA versus mini-incision unicompartmental knee arthroplasty. J Knee Surg. 2006 Apr;19(2):112-6. Return to sport - The majority of patients returned to sports and recreational activity UKA - However, the numbers of different disciplines patients were engaged in decreased as well as the extent of activities. - Activities in which most patients participated were primarily low- or midimpact. - Patients scored higher on the SF-36 than age-related norms, which might be due to the patient-selection process for unicompartmental knee arthroplasty and geographical differences. Naal et al Return to sports and recreational activity after unicompartmental knee arthroplasty. AJSM, 2007 Conclusion • UKA is a valid option to address the unicompartmental degenerated knee • Age is not anymore a limitation, assuming that surgery is correctly performed • Young patients can benefit from this procedure, including those who seek for sport activities 15 6/30/2014 VuMedi Webinar HTO vs UKR Mobile UKR D Murray Disclosure: Personal & Institutional support - Biomet High Activity patients • Concern –? Causes UKR wear & failure • Fixed bearing UKR – Wear inevitable esp second decade – Small contact area, high contact stress – Thin polyethylene • Normal Knee – Wear prevented by meniscus – Reproduce function of meniscus Minimise wear • Reproduce meniscus –Full congruent contact in all positions • Only achieved with –Mobile bearing –Spherical femur 1 6/30/2014 Oxford knee 1976 Articulation unchanged • Femur spherical • Tibia flat • Mobile Bearing (1mm error) – Fully congruent - low wear – Unconstrained - low loosening 20 year wear in vivo • RSA (Kendrick et al 2010) • 7 knees, Phase 2 • Wear 0.4mm (max 0.6mm) • Rate 0.02mm/yr (max 0.03) • Order of magnitude less than fixed • Ideal for young active patients Survival % Independent Results (Svard 2006) 683 Oxford UKR 20 yr survival 92% CI 15 Better than other UKR No failures due to wear OA progression 2% at 20 yrs Years 2 6/30/2014 Phase 1 study (Svard 2013) • 1983 to 1988 – 25 to 30 years ago • 125 implants (104 patients) • 80% Dead, alive reviewed mean 25yr • 90% Definitive knee replacement with no revision & Good/Excellent HSS score • No TKR has better results Medial OA – optimal treatment • Young (? <60 25% of cases) –UKR v Osteotomy –Debate – no good comparative evidence • Old (? >60 75% of cases) –UKR v Osteotomy –UKR better - no debate UKR v HTO in elderly • UKR definite solution – Rapid recovery, Low morbidity, Good function – 90% patients die with without revision and with good clinical outcome • HTO – Results not so good – 15yr Comparative study (Weale 1994) – Meta-analysis (Virolainen) 3 6/30/2014 UKR v HTO in young Controversial issues • Bone-on-bone or Partial thickness • Activity level • Extent of varus deformity • ACL deficiency UKR v HTO in young Indications • Bone – on – bone medial OA – UKR reliably relieve symptoms, good long term results – HTO – not so reliable • Partial thickness cartilage loss – Diagnose – Xray or arthroscopy – UKR not reliable – contra-indicated – ? HTO ideal if associated with Varus PTCL compared to Bone Exposed (BE) & Bone loss (BL) • PTCL worse score and greater variability than BE or BL (OKS 36 v 43) 36 OKS • PTCL 21% worse or no substantial improvement (ΔOKS<6). BE & BL all substantial improvement 48 24 12 p < 0.001 0 PTCL BE BL Groups • 4 complications (pain related) all PTCL (14%) Gulati et al (2010) 4 6/30/2014 Partial thickness loss • UKR –Not reliable – contraindicated –Rare to have severe symptoms • HTO –PTCL + varus ? Best indication –PTCL without varus ? Not indicated Bone-on-bone HTO v UKR • No RCT in young • Age matched comparison (mean 55yr) – Distraction osteoclasis 76, 6yr mean – Oxford UKR 78, 6yr mean – OKS (0-48) - HTO 27 UKR 38 – Perhaps not highly active • HTO 10yr survival 66% • Other series 60% - 80% Oxford age < 60yrs (mean 55, n=52, Price et al ESSKA 2000) >60 <60 • 15yr 92% • No significant difference (p=0.8) • Appears to be reliable in young patients (50s) Years post operation 5 6/30/2014 <50yr, 7 centre study 107 patients, Mean age 47 3 revisions: 2 for pain, 1 dislocation 7 yr survival = 98% (n=24) 10 yr survival = 91% (n=9) High level activity subgroup 100 90 80 • Does it compromise UKR outcome? • Analysis of 1000 Oxford UKR with 5 to 15yr follow-up • Overall with increased activity – Increased 12yr survival (p=0.025) – Increased OKS (p<0.01) • High activity does not cause failure • Pandit 2014 12yr survival 70 OKS 60 50 40 30 20 10 0 0-1 2 3 4 5 ≥6 Tegner High level activity in UKR • High activity group patients (Tegner ≥ 5) – (Tegner 5 = Heavy labour, competitive cycle, jog uneven ground) – n=115 – 12 year survival 97.3% (95%CI: 92-99). – OKS 45 (SD 5) – KSS-O 82 (SD 16) KSS-F 95 (10) • Activity does not compromise outcome • Not contraindication, can be recommended 6 6/30/2014 High activity in HTO • Tegner score ≥ 5 • Bone on bone arthritis • 12 year survival ??? – not nearly 97% • Mean 6 year clinical follow-up – OKS ??? – not as good as 45 Activity - summary • UKR function well so high activity achieved • High activity does not cause failure • Is high activity so reliably achieved after HTO and if so is long term survival so good? Tibia vara & medial OA • Determine site and severity of deformity • Intra-articular (usually 5º to 10º) – Corrected by operation • Extra-articular (usually 0º to 10º) – Tibia vara – Not corrected by operation, • Alignment restored to pre-disease state • ? Does tibia vara compromise outcome? 7 6/30/2014 Tibia Vara & Oxford UKR • Incidence of tibia vara – 5º tibia vara – 10º tibia vara 20% 5% • Tibia vara – Does not cause long term failure – Does not compromise function • Tibia vara not contra-indication ACLD & medial OA • Primary ACLD with secondary medial OA • Postero-medial tibial defect • Combined UKR & ACLR if – Young and active – Bone on bone – Normal MCL & lateral side (stress Xray) Technique • Depends on presenting symptoms • Pain – Simultaneous procedure – Open, BTB • Instability – ACL first – Arthroscopic, Hamstring – UKR if symptoms persist 8 6/30/2014 Results • 52 cases (Weston-Simons 2013) • Mean age 51yr (36-57) • Mean follow up 5yr (1 – 10) • 10yr survival 91% – 2 failures – infected, lat OA • Mean OKS 41 • 98% pleased • Kinematically normal Other factors to consider • • • • Predictability – UKR better Speed of recovery - UKR better Cosmesis - UKR better Ease of revision – UKR usually simple (fracture & infection) – HTO variable (? Opening wedge easier) Summary • Medial OA, bone-on-bone, intact ACL – UKR better (function, survival, etc) • Partial thickness loss – UKR contraindicated – ? HTO if associated varus • Very young (<40), Very high activity (contact sport), ACLD deficient – Still debatable (we do UKR) 9 6/30/2014 The Role of Osteotomy around the knee Ph. Lobenhoffer Disclosures: I have no financial relationship to techniques or products mentioned in this presentation AO Trauma Europe Hannover – München - Innsbruck – Bozen Frontal plane alignment Constitutional Varus deformity: • 32% males • 17% females HKA 0° ALL MALE HKA: mechanical axis femur / tibia Bellemans CORR 2012 Constitutional Varus J. Victor CORR 2013 knee outwards foot inwards WBL shifts medial 1 6/30/2014 Constitutional Valgus Knee inwards foot outwards WBL shifts lateral Epidemiology Osteoarthritis is a disease of mechanics D.T. Felson JAMA 2013 A frontal plane deformity more than 3° leads to osteoarthritis and should be corrected 4 degrees of deformity: 3 x risk for OA Progression 10 to 20 x faster with deformity Felson 2013, Brouwer 2007, Sharma 2001, 2009, 2010, 2012, Cerejo 2002 Framingham, MOST, other studies Biomechanical Study 6 human knees Axial load in mechanical testing system (mts) in extension Bi-cardanic fixation Ligaments and menisci intact Agneskirchner, Hurschler*, Lobenhoffer , Arthroscopy 23, 2007 2 6/30/2014 Varus Malalignment lateral Pressure++ medial 0% 50%100% 0% Agneskirchner, Hurschler, Lobenhoffer Arthroscopy 23, 2007 Open wedge HTO lateral 0% 50%100% Pressure ++ medial WBL to 62% HTO 9mm, MCL 100% released Agneskirchner, Hurschler, Lobenhoffer Arthroscopy 23, 2007 Indication for osteotomy • Congenital deformity • Posttraumatic deformity • Unilateral Osteoarthritis 3 6/30/2014 Frontal plane alignment and correction Constitutional deformity Frontal plane alignment and correction Intraarticular defect Patient criteria Metaphyseal deformity (TBVA) Tibial Bone Varus Angle Tibial Bone Varus Angle Good / excell. 10-y. results >5° 2-5° 0-2° <0° 83% 71% 56% 36% TBVA > 5° TBVA = 0° Bonnin,Orthopäde 2004 Niemeyer Arthroscopy 2009 4 6/30/2014 HTO Survival Rate 5 Jahre 10 Jahre Insall 85% 66% Yashuda 63% 18% Berman 77% > 10 Jahre 62% 59% Cochrane Database : 78% 70% Rudan 50% Brouwer et 28% al 2007 Matthews Rininapoli 73% Silver Evidence: 46% 57% 43% Hernigou 90% 45% 70% of patients benefit Aglietti 96% 78% 57% 10 Levigne from an 69%osteotomy for 54% Gstöttner 94% 80% 54% years Van Raaij 75% Ivarsson Akizuki 98% Flecher 90% 85% Billings 85% 53% HTO Survival Rate Insall Yashuda Berman Rudan 5 Jahre 10 Jahre 85% 66% > 10 Jahre 18% Spahn 63% G, KSSTA 2013 77% 62% 59% 46 studies HTO 70% 78% Matthews 50% 28% 73% 5-8 years after HTO: 46% Ivarsson 57% 43% further45%surgery Hernigou91% no 90% Rininapoli Aglietti 96% 78% 57% 98% 90% 69% 9 – 12 years after HTO:54% Gstöttner 94% 80% 54% surgery Van Raaij84% no further 75% Levigne Akizuki Flecher Billings 85% 85% 53% Valgus HTO Closed Wedge Lateral translation of shaft Impaction medial hinge Loss of correction Pape et al. Orthopäde 2/2004 42 Pat RSA-Analysis HTO Convent. implant > 8° correction week 0 – 3: 3 mm. fragment movement 5 6/30/2014 HTO lateral closed wedge Lesions of peroneal nerve Coventry 1988 3.3% 30 Osteotomies Jackson 1974 11,9 % 229 Osteotomies Motor branches of peroneal nerve endangered by fibula osteotomy Vainionpää 1981 2% 103 Osteotomies Aydogdu 2000 27% (EMG) 11 Osteotomies Kirgis, A., JBJS 1992 Open Wedge HTO W. Blauth 1986 P.Hernigou 1987 No fibula osteotomy No risk for peroneal nerve No muscle detachment Only 1 osteotomy cut Intraoperative fine-tuning No leg shortening GC Puddu 1999 Problems Open Wedge Osteotomy • Stability • Implant failure • Slope increase • Pseudarthrosis Lobenhoffer KSSTA 2003, Paccola KSSTA 2004, Jakob A´scopy 2004 6 6/30/2014 Open wedge biplanar Tomofix Increased stability Rapid healing full weight-bearing Locking screws 3 weeks postop Hannover 1998 – 2000: 101 HTO spacer plates 6 implant failures Hannover 2001 – 2006: 807 HTO with Tomofix no implant failure Lobenhoffer KSSTA 2003 Percutaneous Plate fixator Tomofix Distance holders • Subcutaneous placement • No compression of MCL, Pes anserinus Spontaneous bone healing No substitute or graft necessary 2 Y. postop Elastic motion induces callus formation 7 6/30/2014 Stability RSA studies Heerwaarden 2006: 42 cases open wedge Tomofix no relevant migration, no difference to closed wedge Tomofix Heerwaarden Acta Orthop Scan2010: 14 vs 23 patients full weight-bearing /partial weight bearing no differences after one year Immediate full weight bearing allowed Brinkman, Lobenhoffer, Agneskirchner, Staubli, Wymenga, Heerwaarden JBJS (Br) 12, 2008 TomoFix TM retrospective study Functional outcome assessment in patients treated with open wedge high tibial osteotomy (HTO) for knee osteoarthritis using TomofixTM . 533 patients, 3 centers, op. 4/2004 to 4/2006 75% follow-up rate, BMI 27, 9,8 mm opening AO Foundation Clinical Investigation • • • • • • • D. Freiling S. Meyer S. Friedmann P. Lobenhoffer A.Staubli S. Schröter D. Hoentzsch Flörkemeier et al, KSSTA 1/2013 8 6/30/2014 Oxford Knee Score (OKS) Subjective score Internationally accepted Available in Englisch Translated/Validated by AOCID 12 questions, 5 answers (excellent 4 P., bad 0 P.) 48 points: excellent result 0 points: bad result Comparison with Unicondylar and Total Knee Present version of OKS: 48 points best result 0 points worst results Ø 43 (0-48) Results better than UKA, TKA No correlation to age Ø 51,6 (20-60) 9 6/30/2014 No correlation to stage of osteoarthritis Ø 51,6 (20-60) Activity 6 Mo. after Tomofix both sides 6 Mo. after Tomofix right side 3 Mo.after Tomofix right side 3 Mo. after Tomofix right side . Studies Tomofix Salzmann GM, Imhoff, AB et al AJSM 2009 65 patients Tomofix 36 months postop 91% engaged in sports activity 2 sessions /4 hours per week Lysholm 70, Tegner 4,3 Downhill skiing, mountain biking 10 6/30/2014 W., U., 51 y., male former German champion 400 m running orthopaedic surgeon 2 x arthroscopic debridement, medial meniscectomy Medial pain ADL MPTA 85° W., U., 51 y. PreOP Plan Software: 7° correction, 10 mm opening W., U., 51 y. 6 days 5 weeks postop postop 65 days weeks postop postop FWB and working 5 weeks postop 11 6/30/2014 W., U., 51 y., male, 9 months postop 9 months postop: 10 days trekking up to 6000 m. no pain! Age of osteotomy patients Hannover 1100 patients Mean age: 40,5 years Instability Osteoarthritis Instab + OA Deformity years Effect of Tibial Slope on Stability PCL Instability Flexion Osteotomy: Slope increase ACL Instability 10° Extension Osteotomy: Slope reduction 12 6/30/2014 Biomechanical Study • Human cadaver joints • Flexion osteotomy • Gradual increase of slope (0° 5 ° 10° 15° 20°) • Computer-regulated isokinetic extension movement of knee (Knee Kinemator) J. Agneskirchner, C. Hurschler, A. Imhoff, P. Lobenhoffer Winner of AGA DonJoy Award 2004 Archives Orthop Trauma Surg 4/2004 Results Kinematics PCL transsected Durchtrennung hinteres Kreuzband posterior subluxation of tibia reduction by slope increase Slope reduction in anterior knee instability Tibial Slope 0° Anterior Translation force 130 N 5° 235 N 10° 340 N 15° 443 N 20° 541 N 10° slope difference produce 6,8 mm. anterior translation of tibia in monopedal stance 70 Kg, 20° Flexion, monopedal stance M. Bonnin, Lyon 1990 13 6/30/2014 Site of deformity Single level osteotomy producing joint line obliquity Femoral SCO correction What have we learnt? Not all deformities can be adressed at the tibia The importance of the joint line 14 6/30/2014 Femur biplanar closed wedge osteotomy technique post 2/3 femur: transverse bone cuts of closing wedge along K-wires ant 1/3 femur: ascending bone cut parallel to posterior femur cortex Design new Tomofix MDF plate MIPO tapered tip Antecurvation Twisted shaft -> screws all point in one direction 2 most proximal holes allow locking only Twisted shaft Optimal anatomic fit Even load distribution for increased stability Less invasive Optimized for osteotomies 46 www.sportsclinicgermany.com M.S., male, 46 y., tennis trainer 15 6/30/2014 M.S.,male, 46 y. Double osteotomy LDFA 90° MPTA 82° Femur closed wedge 7 mm Tibia closed wedge 11 mm Double osteotomy Femur closed wedge 7 mm Tibia closed wedge 11 mm 1 week postop 16 6/30/2014 Double osteotomy 4 days postop Double osteotomy Femur closed wedge 7 mm Tibia closed wedge 11 mm 6 weeks postop Double osteotomy 6 weeks postop 17 6/30/2014 Double osteotomy Left side: Femur closed wedge 7 mm Tibia closed wedge 11 mm 6 weeks postop left side Osteotomy versus Uni 2001 – 2013 2049 osteotomies 1752 Uni 2013: 20% DFO, DO Osteotomy Uni 2013 Key Points Renaissance of osteotomy Osteotomy around the knee works Best indication metaphyseal deformity HTO can treat ACL/PCL deficiency Plate fixator/biplanar technique is safe Osteotomy stimulates regeneration in involved compartment 18 6/30/2014 19 6/30/2014 Technical Pearls in OW HTO Avoiding Complications Hatem Said Prof. Orthopaedic & Trauma Assiut University, Egypt SICOT Editorial Secretary No Financial Disclosures Complications 1. Overstuffing the joint 2. Lateral cortex break (6-20%) 3. Intra-articular Fracture (3%) 4. Changing the slope (1%) 5. Delayed (12%) / Nonunion (3%) 6. Loss of correction (1%) 7. Joint Line Tilt. Martin et al, JAAOS 2014 1 6/30/2014 Technique Non- Locked - Short Lateral Hinge BG Locked T No BG 1- Overstuffing • Proper MCL release Lobenhoffer et al, 2007 MCL Release 2 6/30/2014 2- Lateral cortex break • 1 cm from lat. Cortex – Too short – Intra-artic fr. • Lateral Hinge – Non-Locked plates • Locked plates: – change principle - procedure – Positional Fixation – plate Lateral cortex break • Osteotomy too long • Large opening • Opening of lateral cortex. Lat. break - Ttt • Expose Lateral hinge • Axial & Valgus Pr. – Lat. cortex • Staples 3 6/30/2014 Intraop 1m 3- Intra-articular fractures • Osteotomy: – Too high – Too short • Use Image intensifier • Saw Under Wire Intra-articular Fr. 7 wks 4 6/30/2014 Displaced: Loosen screws, valgus force, Lag screw. Intra-op 5 weeks 4- Changing the slope Ant 9 Deg. Lateral Medial Post 5 6/30/2014 • Inc Slope: – PCL deficient • Dec Slope – ACL Def PCL/Varus: 15 Deg. 5- Delayed healing: • 65% Locked plates – 10% length Roderer et al, 2014 6 6/30/2014 5- Non Union 13 m • Mechanical – Inadequate fixation – Lateral cortex break • Not Biological – No BG • El-Assal et al. KSSTA 2010 Long fixation + grafting 2.5 m 7 6/30/2014 6- Loss of Correction: • Undercorrection • Weak fixation – Osteoporotic bone • Locked plates 7- Joint Line Tilt: Valgus 10 Summary • MCL release • Locked Plates: – Lateral Cortex Break – Intra-artic Fr. • • • • Slope Delayed / Nonunion Loss of correction Joint Line Tilt 8
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