Total Knee Arthroplasty in Total Knee Arthroplasty in Valgus kneeValgus knee

H.Makhmalbaf MDH.Makhmalbaf MDConsultant Knee surgeonConsultant Knee surgeon

Mashad UniversityMashad University

The Typical patientThe Typical patient

Sever valgus deformitySever valgus deformityElderly woman in7th or8th decadeElderly woman in7th or8th decadeHas had “knock knees” Has had “knock knees” Also had patellofemoral problemsAlso had patellofemoral problemsValgus deformity progressesValgus deformity progressesLoss of lateral joint spaceLoss of lateral joint spaceAttenuation of MCLAttenuation of MCL

The typical patientThe typical patient

PFJ involvement & patella dysplasia on PFJ involvement & patella dysplasia on X-RayX-RayPatella subluxation & concave patellaPatella subluxation & concave patellaPatella alta & a very thin patellaPatella alta & a very thin patellaChondrocalcinosis & calcification of Chondrocalcinosis & calcification of meniscimenisciLong leg film of tibia shows valgus bowLong leg film of tibia shows valgus bow

The typical patientThe typical patient

The valgus tibia is problematic if using The valgus tibia is problematic if using intramedullary guide intramedullary guide The long leg film is necessary to templateThe long leg film is necessary to templateThe diagnosis is usually OA or RAThe diagnosis is usually OA or RAHypermobile knee or hyperextentionHypermobile knee or hyperextentionIn RA might have stiff knee & flexion cont.In RA might have stiff knee & flexion cont.

Clinical features of valgus vs varusClinical features of valgus vs varus

Valgus knees tolerate significant damageValgus knees tolerate significant damageIn windblown knees varus knee is more In windblown knees varus knee is more symptomaticsymptomaticVarus knee should be operated on 1Varus knee should be operated on 1stst

Source of deformity is also differentSource of deformity is also differentMedial tibial plateau is deficient & tibial Medial tibial plateau is deficient & tibial joint line in sever varus in varus kneesjoint line in sever varus in varus kneesThe femoral joint line is still in 5-7 valgusThe femoral joint line is still in 5-7 valgus

Valgus vs varus kneeValgus vs varus knee

In valgus knees, is from the femurIn valgus knees, is from the femurThe tibial joint line usually in neutralThe tibial joint line usually in neutralThe femoral joint line is in marked valgusThe femoral joint line is in marked valgusDeformity due to hypoplasia of lat.femoral Deformity due to hypoplasia of lat.femoral condylecondyleBoth distally & posteriorlyBoth distally & posteriorlyThe tibial defect in valgus is containedThe tibial defect in valgus is contained

Variants of valgusVariants of valgus

Based on degree of deformityBased on degree of deformityStatus of MCL, osseous deficiency &Status of MCL, osseous deficiency &The amount of release must be performedThe amount of release must be performedVariant I: mild & correctable deformityVariant I: mild & correctable deformityVariant II: greater deformity ,intact soft Variant II: greater deformity ,intact soft tissuetissueVariant III: stretched MCL, Marked bone Variant III: stretched MCL, Marked bone loss & deformity & lateral contractureloss & deformity & lateral contracture

Type of prosthesisType of prosthesis

In variant I: P CR or PS may be usedIn variant I: P CR or PS may be usedIn variant II: may require a PS implantIn variant II: may require a PS implantInvariant III: a PSC (constrained) should Invariant III: a PSC (constrained) should be usedbe usedComplete set of instruments if preferred Complete set of instruments if preferred

Lateral femoral condyle hypoplasiaLateral femoral condyle hypoplasia

Is present in sever valgus deformityIs present in sever valgus deformityExists both distally & posteriorlyExists both distally & posteriorlyIn distal femoral resection don’t cut to the In distal femoral resection don’t cut to the defectdefectThe deficiency must be augmentedThe deficiency must be augmentedIf not, causes large extension gapIf not, causes large extension gapAnd elevation of joint lineAnd elevation of joint lineAnd mid-flexion laxity, distorting kinematicAnd mid-flexion laxity, distorting kinematic

The angle of DF cutThe angle of DF cut

5 degree is preferred5 degree is preferred7 degree cut is better for balance but?7 degree cut is better for balance but?55oo or less to overcorrect the deformity or less to overcorrect the deformityLess tension on MCL on WBLess tension on MCL on WBBut needs more lateral releaseBut needs more lateral releaseDistal metaphyseal bow Distal metaphyseal bow More medial point of entrance in the notch More medial point of entrance in the notch

Balancing the knee in flex.& Balancing the knee in flex.& extensionextension

Create symmetric flexion extension gapsCreate symmetric flexion extension gapsValgus knees could be balanced in flexion Valgus knees could be balanced in flexion & extension independently& extension independentlyIn flexion the tissues are not tightIn flexion the tissues are not tightNor the medial tissues are lax in flexionNor the medial tissues are lax in flexionDraw Whiteside line & transepicondylar axDraw Whiteside line & transepicondylar axIn sever valgus int rotation of femoral In sever valgus int rotation of femoral component is necessarycomponent is necessary

Flexion extension balanceFlexion extension balance

Lateral release, after bone cutsLateral release, after bone cutsPut spacers, varus & valgus testsPut spacers, varus & valgus testsInverted cruciform releaseInverted cruciform releaseLCL, poplliteal, & Biceps tendon releaseLCL, poplliteal, & Biceps tendon releasePS in sever valgus & CR in mild onePS in sever valgus & CR in mild oneSurgical approachSurgical approach

SummarySummary

Associated with PFJ diseaseAssociated with PFJ diseaseLat femoral condyle hypoplasiaLat femoral condyle hypoplasiaMedial laxity, a valgus tibial bowMedial laxity, a valgus tibial bowConservative bone cutsConservative bone cutsCruciform release of ITB & capsuleCruciform release of ITB & capsuleProtect peroneal nerveProtect peroneal nervePS or CR kneePS or CR knee

Thank youThank you