Osteoarthritis Osteoarthritis of of

The KneeThe Knee

Osteoarthritis of The KneeOsteoarthritis of The Knee

I.I. Overview Overview EpidemiologyEpidemiology DefinitionDefinition Risk FactorsRisk Factors

II.II. Clinical Approach to Knee Pain Clinical Approach to Knee Pain

III.III. Differential Diagnosis Differential Diagnosis

IV.IV. Diagnosis of Knee OADiagnosis of Knee OA

V.V. ManagementManagement LifestyleLifestyle Medical Medical SurgicalSurgical

Overview: EpidemiologyOverview: Epidemiology

• Knee OA most common cause of disability in adultsKnee OA most common cause of disability in adults

• Decreased work productivity, frequent sick days Decreased work productivity, frequent sick days

• Highest medical expenses of all arthritis conditionsHighest medical expenses of all arthritis conditions

• Symptomatic Knee OASymptomatic Knee OA

– More than 11% of persons > 64yoMore than 11% of persons > 64yo

Overview: DefinitionOverview: DefinitionArthritis vs. ArthrosisArthritis vs. Arthrosis

Gradual loss of articular cartilage in the knee jointGradual loss of articular cartilage in the knee joint• 3 articulations:3 articulations:

1)1) Lateral condyles of the femur and tibiaLateral condyles of the femur and tibia

2)2) Medial condyles of the femur and tibiaMedial condyles of the femur and tibia

3)3) Patellofemoral jointPatellofemoral joint

Damage caused by a complex interplay of joint Damage caused by a complex interplay of joint

integrity, biochemical processes, genetics, and integrity, biochemical processes, genetics, and

mechanical forcesmechanical forces

Anatomy of The KneeAnatomy of The Knee

Anatomy of The KneeAnatomy of The Knee

Overview: Risk FactorsOverview: Risk Factors

• AgeAge

• FemaleFemale

• Obesity ( most important modifiable)Obesity ( most important modifiable)

• Previous knee injuryPrevious knee injury

• Lower extremity malalignmentLower extremity malalignment

• Repetitive knee bendingRepetitive knee bending

• High impact activitiesHigh impact activities

• Muscle weaknessMuscle weakness

Osteoarthritis of The KneeOsteoarthritis of The Knee

I.I. Overview Overview EpidemiologyEpidemiology DefinitionDefinition Risk FactorsRisk Factors

II.II. Clinical Approach to Knee Pain Clinical Approach to Knee Pain

III.III. Differential Diagnosis Differential Diagnosis

IV.IV. Diagnosis of Knee OADiagnosis of Knee OA

V.V. ManagementManagement LifestyleLifestyle Medical Medical SurgicalSurgical

EvaluationEvaluationHistory:History:

•Site/Severity:Site/Severity:

•Onset:Onset:

•Character:Character:

•Radiation:Radiation:

•Alleviation:Alleviation:

•Time:Time:

•Exacerbation:Exacerbation:

•Sx associated:Sx associated:

EvaluationEvaluationHistory:History:

•Site/Severity: Site/Severity: medial / lateral – pain scoremedial / lateral – pain score

•Onset: Onset: gradual, no acute traumagradual, no acute trauma

•Character: Character: ache, joint soreness ache, joint soreness

•Radiation: Radiation: present / absentpresent / absent

•Alleviation: Alleviation: rest, medicationrest, medication

•Time: Time: how many yrs/ recent episodehow many yrs/ recent episode

•Exacerbation: Exacerbation: eg. walking ½ mile, inclineseg. walking ½ mile, inclines

•Sx associated: Sx associated: swelling / instabilityswelling / instability

EvaluationEvaluation

Physical ExamPhysical Exam

• Height, weight,BMIHeight, weight,BMI

• joint line tendernessjoint line tenderness

• ROM of knees: L and RROM of knees: L and R

• Lachmann’s/valgus/varus stress testSLachmann’s/valgus/varus stress testS

• Patellar mobilityPatellar mobility

• Genu varus (bowlegged) valgus alignmentGenu varus (bowlegged) valgus alignment

• Type of gait (antalgic)Type of gait (antalgic)

Clinical Approach to Knee PainClinical Approach to Knee Pain

Varus Test (LCL)Varus Test (LCL)Valgus Test (MCL)Valgus Test (MCL)

McMurray ManeuverMcMurray Maneuver(menisci)(menisci)

Lachman Test (ACL)Lachman Test (ACL)

Duck Waddle Duck Waddle (stability)(stability)

Clinical Approach to Knee PainClinical Approach to Knee Pain

TestsTests

• FBC, ESR, RFFBC, ESR, RF

• ArthrocentesisArthrocentesis

• X-rays (3 views)X-rays (3 views)– Weight-bearing AP Weight-bearing AP – LateralLateral– Tangential Patellar (Sunrise)Tangential Patellar (Sunrise)

• MRIMRI

Osteoarthritis of The KneeOsteoarthritis of The Knee

I.I. Overview Overview EpidemiologyEpidemiology DefinitionDefinition Risk FactorsRisk Factors

II.II. Clinical Approach to Knee Pain Clinical Approach to Knee Pain

III.III. Differential DiagnosisDifferential Diagnosis

IV.IV. Diagnosis of Knee OADiagnosis of Knee OA

V.V. Management Management LifestyleLifestyle Medical Medical SurgicalSurgical

Differential Diagnosis of Knee PainDifferential Diagnosis of Knee Pain

Medial PainMedial Pain• OAOA

• MCLMCL

• MeniscusMeniscus

• BursitisBursitis

Diffuse PainDiffuse Pain• OAOA

• Infectious arthritisInfectious arthritis

• Gout, pseudogoutGout, pseudogout

• RARA

Lateral PainLateral Pain• OAOA

• LCLLCL

• MeniscusMeniscus

• Iliotibial band syndromeIliotibial band syndrome

Anterior PainAnterior Pain• OAOA

• Patellofemoral syndromePatellofemoral syndrome

• Prepateller bursitisPrepateller bursitis

• Quadriceps mechanismQuadriceps mechanism

Osteoarthritis of The KneeOsteoarthritis of The Knee

I.I. Overview Overview EpidemiologyEpidemiology DefinitionDefinition Risk FactorsRisk Factors

II.II. Clinical Approach to Knee Pain Clinical Approach to Knee Pain

III.III. Differential Diagnosis Differential Diagnosis

IV.IV. Diagnosis of Knee OADiagnosis of Knee OA

V.V. ManagementManagement LifestyleLifestyle Medical Medical SurgicalSurgical

Diagnosis of Knee OADiagnosis of Knee OA

Classic Clinical CriteriaClassic Clinical Criteria– established by ACR, 1981established by ACR, 1981– sensitivity 95%, specificity 69%sensitivity 95%, specificity 69%

knee painknee pain plus at least 3 of 6 characteristics: plus at least 3 of 6 characteristics:• > 50 yo> 50 yo• Morning stiffness < 30 minMorning stiffness < 30 min• CrepitusCrepitus• Bony tendernessBony tenderness• Bony enlargementBony enlargement• No palpable warmth No palpable warmth 55

Diagnosis of Knee OADiagnosis of Knee OAClassification TreeClassification Tree• Clinical symptomsClinical symptoms• Synovial fluidSynovial fluid

1.1. WBC<2000/mmWBC<2000/mm33

2.2. Clear colorClear color3.3. High ViscosityHigh Viscosity

• X-raysX-rays1.1. OsteophytesOsteophytes2.2. Loss of joint spaceLoss of joint space3.3. Subchondral sclerosisSubchondral sclerosis4.4. Subchondral cystsSubchondral cysts

Confirmed by arthroscopyConfirmed by arthroscopy (gold standard)(gold standard)

No OANo OA

Sensitivity 94 %; Specificity 88 %

Diagnosis of Knee OADiagnosis of Knee OA

Osteoarthritis of The KneeOsteoarthritis of The Knee

I.I. Overview Overview EpidemiologyEpidemiology DefinitionDefinition Risk FactorsRisk Factors

II.II. Clinical Approach to Knee Pain Clinical Approach to Knee Pain

III.III. Differential Diagnosis Differential Diagnosis

IV.IV. Diagnosis of Knee OADiagnosis of Knee OA

V.V. ManagementManagement LifestyleLifestyle Medical Medical SurgicalSurgical

Management: LifestyleManagement: Lifestyle• Weight lossWeight loss

– Nutrition referralNutrition referral

• Exercise ProgramExercise Program– PT referral PT referral – Quadriceps strengthening Quadriceps strengthening – ROM exercisesROM exercises– Low impact activities e.g. swimming, biking Low impact activities e.g. swimming, biking 77

• Ambulatory assist devicesAmbulatory assist devices– CaneCane– Walker Walker

• InsolesInsoles• Unloader knee bracesUnloader knee braces

Management: LifestyleManagement: Lifestyle

Varus (bowlegged) vs Valgus (knock-kneed)Varus (bowlegged) vs Valgus (knock-kneed)

Unloader BraceUnloader Brace

Management: MedicalManagement: Medical

• Glucosamine/ChondroitinGlucosamine/Chondroitin• AcetaminophenAcetaminophen• NSAIDsNSAIDs• Cox-2 inhibitorsCox-2 inhibitors• OpioidsOpioids• Intraarticular injectionsIntraarticular injections

– GlucocorticoidsGlucocorticoids

– HyaluronansHyaluronans

Management: MedicalManagement: Medical

• Glucosamine/ChondroitinGlucosamine/Chondroitin– 1500 mg/1200 mg daily (Rs. 2500 /month)1500 mg/1200 mg daily (Rs. 2500 /month)

– Glucosamine: building block for glycosaminoglycansGlucosamine: building block for glycosaminoglycans

– Chondroitin: glycosaminoglycan in articular cartilageChondroitin: glycosaminoglycan in articular cartilage– What does studies show (What does studies show (GAIT study, NEJM, Feb 23, 2006)GAIT study, NEJM, Feb 23, 2006)

• Multicenter, double blind, placebo-controlled, 24 wks, N=1583Multicenter, double blind, placebo-controlled, 24 wks, N=1583

• Symptomatic mild or moderate-severe knee OASymptomatic mild or moderate-severe knee OA

• Infrequent mild side effects e.g. bloatingInfrequent mild side effects e.g. bloating

• For mild OA, not better than placeboFor mild OA, not better than placebo

• For moderate-severe OA, combination showed benefit For moderate-severe OA, combination showed benefit 88

– Patient satisfactionPatient satisfaction

Management: MedicalManagement: Medical

• AcetaminophenAcetaminophen– Indication: mild-moderate painIndication: mild-moderate pain

– 1000 mg Q6h PRN1000 mg Q6h PRN

– Better than placebo but less efficacious than NSAIDs Better than placebo but less efficacious than NSAIDs 99

– Caution in advanced hepatic diseaseCaution in advanced hepatic disease

• NSAIDsNSAIDs– Indication: moderate-severe pain, failed acetaminophenIndication: moderate-severe pain, failed acetaminophen

– GI/renal/hepatic toxicity, fluid retentionGI/renal/hepatic toxicity, fluid retention

– If risk of GIB, use anti-ulcer agents concurrentlyIf risk of GIB, use anti-ulcer agents concurrently

– Agents have highly variable efficacy and toxicityAgents have highly variable efficacy and toxicity

Management: MedicalManagement: Medical• NSAIDsNSAIDs

1010NSAIDS DosesNSAIDS Doses

Management: MedicalManagement: Medical• Cox-2 inhibitorsCox-2 inhibitors

– Indication: mod-severe pain, failed NSAID, risk of GIBIndication: mod-severe pain, failed NSAID, risk of GIB

– OA pain relief similar to NSAIDsOA pain relief similar to NSAIDs

– Fewer GI events e.g. symptomatic ulcers, GIBFewer GI events e.g. symptomatic ulcers, GIB

– Celecoxib 200 mg dailyCelecoxib 200 mg daily

– GI/renal toxicity, fluid retentionGI/renal toxicity, fluid retention

– Increased risk of CV events? Increased risk of CV events? • APC Trial: 700 pts each assigned to placebo, 200 BID, 400 BIDAPC Trial: 700 pts each assigned to placebo, 200 BID, 400 BID

– Increased risk at higher dosesIncreased risk at higher doses

• CLASS Trial: 8,000 pts compared Celecoxib vs IbuprofenCLASS Trial: 8,000 pts compared Celecoxib vs Ibuprofen

– Similar risk to IbuprofenSimilar risk to Ibuprofen

Management: MedicalManagement: Medical• Opioid AnalgesicsOpioid Analgesics

– Indication: Indication: • Moderate-severe painModerate-severe pain• Acute exacerbationsAcute exacerbations• NSAIDs/Cox-2 inhibitors failed or contraindicatedNSAIDs/Cox-2 inhibitors failed or contraindicated

– Oxycodone synergistic w/ NSAIDs Oxycodone synergistic w/ NSAIDs 1313

– Tramadol/acetaminophen vs codeine/acetaminophenTramadol/acetaminophen vs codeine/acetaminophen• Similar pain relief Similar pain relief 1414

– Avoid long-term useAvoid long-term use

– Caution in elderlyCaution in elderly• Confusion, sedation, constipationConfusion, sedation, constipation

Management: MedicalManagement: MedicalIntraarticular InjectionsIntraarticular Injections

• GlucocorticoidsGlucocorticoids

– Indication: pain persists despite oral analgesicsIndication: pain persists despite oral analgesics

– 40 mg/mL triamcinolone (kenalog-40)40 mg/mL triamcinolone (kenalog-40)

– Solution: 5 mL (lidocaine 4 mL + kenalog 1 mL)Solution: 5 mL (lidocaine 4 mL + kenalog 1 mL)

– Limit to Q3months, up to 2 yrsLimit to Q3months, up to 2 yrs

– Effective for short-term pain relief < 12 wksEffective for short-term pain relief < 12 wks

– Acute flare w/in 48 hrs post-injection Acute flare w/in 48 hrs post-injection 1515

Management: MedicalManagement: MedicalIntraarticular InjectionsIntraarticular Injections

• Hyaluronans (e.g. Synvisc)Hyaluronans (e.g. Synvisc)– Indication: pain persists despite other agentsIndication: pain persists despite other agents

– Synthetic joint fluidSynthetic joint fluid

– Pain relief similar to steroid injectionsPain relief similar to steroid injections

– 2 mL injection Qwk x 3, $560-760/series2 mL injection Qwk x 3, $560-760/series

– Medicare reimburses 80%, Medi-cal $455.90Medicare reimburses 80%, Medi-cal $455.90

– 60-70% patients respond, relief up to 6 months60-70% patients respond, relief up to 6 months

– Patient satisfaction Patient satisfaction 16, 1716, 17

Management: MedicalManagement: MedicalIntraarticular InjectionsIntraarticular Injections• TechniqueTechnique

– 23 gauge 1.5 inch needle23 gauge 1.5 inch needle

– Approach accuracy:Approach accuracy:• Lateral mid-patellar 93% Lateral mid-patellar 93% 1818

– Patient supinePatient supine

– Leg straight Leg straight

– Manipulate patella Manipulate patella

– Angle needle slightly posteriorly Angle needle slightly posteriorly

– Inject after drop in resistance or fluid aspiratedInject after drop in resistance or fluid aspirated

Management: AlgorithmManagement: Algorithm

Lifestyle ModificationsLifestyle Modifications AcetaminophenAcetaminophen

NSAIDsNSAIDs

OpioidsOpioids

CelecoxibCelecoxib

Steroid InjectionsSteroid Injections

Hyaluronan InjectionsHyaluronan Injections

Surgical ReferralSurgical Referral

Management: SurgicalManagement: Surgical

When to ReferWhen to Refer• Knee pain or functional status Knee pain or functional status has failed to improve with has failed to improve with non-operative managementnon-operative management

Types of ProceduresTypes of Procedures• Arthroscopic IrrigationArthroscopic Irrigation

• Arthroscopic DebridementArthroscopic Debridement

• High Tibial OsteotomyHigh Tibial Osteotomy

• Partial Knee ArthroplastyPartial Knee Arthroplasty

• Total Knee ArthroplastyTotal Knee Arthroplasty

Management: SurgicalManagement: Surgical

High Tibial OsteotomyHigh Tibial Osteotomy

• Indication:Indication:

– Unicompartmental arthritisUnicompartmental arthritis

– Genu varus or valgusGenu varus or valgus

• Realign mechanical axisRealign mechanical axis

• Age < 60yoAge < 60yo

• < 15 degrees deformity< 15 degrees deformity1919

Management: SurgicalManagement: Surgical

Partial Knee ArthroplastyPartial Knee Arthroplasty

• Indication:Indication:

– Unicompartmental arthritisUnicompartmental arthritis

• Ligaments sparedLigaments spared

• Increased ROMIncreased ROM

• Faster recoveryFaster recovery

• Prosthesis 10-yr survival: 84%Prosthesis 10-yr survival: 84%

• Implant cost –Implant cost – Rs 200000Rs 200000

Management: SurgicalManagement: Surgical

Total Knee ArthroplastyTotal Knee Arthroplasty• Indication:Indication:

– Diffuse arthritisDiffuse arthritis

– Severe painSevere pain

– Functional impairmentFunctional impairment

• Pain relief > functional gainPain relief > functional gain

• ACL sacrificedACL sacrificed

• PCL also may be sacrificedPCL also may be sacrificed

• Prosthesis 10-yr survival: 90%Prosthesis 10-yr survival: 90%

• Implant cost –Implant cost – Rs 200000Rs 200000

Clinical PearlsClinical Pearls• Assess functional lossAssess functional loss

• Knee exam: palpation, ROM, Knee exam: palpation, ROM,

• Nutrition referralNutrition referral

• Exercise program/PT referralExercise program/PT referral

• OrthoticsOrthotics

• Lateral mid-patellar or superolateral approachLateral mid-patellar or superolateral approach• Educate patients about glucosamine/chondroitin, Educate patients about glucosamine/chondroitin,

Cox-2 inhibitors, injectionsCox-2 inhibitors, injections