Post on 01-Apr-2015
OsteoarthritOsteoarthritisisDavid HunterDavid HunterMBBS, PhDMBBS, PhD
Chief of ResearchChief of Research
New England Baptist HospitalNew England Baptist Hospital
Osteoarthritis: Osteoarthritis: Future ShockFuture Shock
20 million 20 million currently currently affectedaffected
40 million affected in 2020
Aging of the population
Increasing obesity
Increased sports related injuries
Prevalence of Knee Pain and Prevalence of Knee Pain and Osteoarthritis in Persons Age 55 Osteoarthritis in Persons Age 55
and Overand Over
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000
People aged 55+years
4 Weeks of kneepain in past year
Knee pain and somedisability
Knee pain andsevere disability
Population of adults aged 55+ years
160*
1250
2500
10000
* The proportion with radiographic evidence in this category is not known, though seems likely to be high
Shading represents the proportion in each category with radiographic evidence of knee osteoarthritis.
Disease BurdenDisease Burden
Most common joint disease in the worldMost common joint disease in the world
Affects the majority of people over the age of 65Affects the majority of people over the age of 65
Prevalence increases with age; 80% of people Prevalence increases with age; 80% of people
over the age of 75 are affected.over the age of 75 are affected.
Females affected twice as commonly.Females affected twice as commonly.
<50% of those with radiographically <50% of those with radiographically
demonstrated OA have symptoms.demonstrated OA have symptoms.
Klippel et al. Klippel et al. Rheumatology. Rheumatology. 1998; 2.1 - 2.81998; 2.1 - 2.8
Brandt. Brandt. Harrison’s Principles of Internal MedicineHarrison’s Principles of Internal Medicine. 1998; 1935 - 1941. 1998; 1935 - 1941
Social and Economic Social and Economic ImpactImpact
In the elderly, accounts for more lower extremity In the elderly, accounts for more lower extremity
disability than any other disease.disability than any other disease.
One in eight days of restricted activity in U.S. One in eight days of restricted activity in U.S.
elderly.elderly.
Accounted for 140 million MD visits, 185 million Accounted for 140 million MD visits, 185 million
bed days and 68 million work days lost per year bed days and 68 million work days lost per year
(as of 1983).(as of 1983).
Total annual cost about $46 billion (U.S., 1990), Total annual cost about $46 billion (U.S., 1990),
25% direct. All arthritis costs equal 2.5% GNP in 25% direct. All arthritis costs equal 2.5% GNP in
1988 and rising1988 and rising
Accounts for most total knee and hip replacementsAccounts for most total knee and hip replacements
William Hunter (1718-William Hunter (1718-1783)1783)
Hunter W. Of the structure and diseases of articular cartilages. Phil Trans 1744;42:514–21.
What is osteoarthritis?What is osteoarthritis?
Myth: Osteoarthritis Myth: Osteoarthritis is a disorder of is a disorder of hyaline articular hyaline articular cartilage.cartilage.
A disease of the A disease of the whole joint:whole joint: Cartilage lossCartilage loss Bone remodeling and Bone remodeling and
sclerosissclerosis Capsular thickening Capsular thickening
and distensionand distension Synovial Synovial
inflammationinflammation Muscle atrophy and Muscle atrophy and
weaknessweakness
Conscious Neurosensory Mapping of the Internal Structures of the Human Knee Without Intraarticular Anesthesia. The American Journal of Sports Medicine 26:773-777 (1998)
Pain sensitive structures in Pain sensitive structures in the normal kneethe normal knee
Joint capsuleJoint capsule LigamentsLigaments Outer third of meniscus, especially Outer third of meniscus, especially
near capsulenear capsule Periosteal and subchondral bonePeriosteal and subchondral bone SynoviumSynovium Soft tissues including fat around Soft tissues including fat around
and deep to patellar tendonand deep to patellar tendon*from Dye, Kellgren and others
Characteristics of OA Characteristics of OA PainPain
Pain with use (e.g. Pain with use (e.g. knee pain with knee pain with climbing stairs)climbing stairs)
Pain relieved with restPain relieved with rest Onset usually insidiousOnset usually insidious AM stiffness absent or AM stiffness absent or
<30 minutes<30 minutes If severe OA, pain can If severe OA, pain can
be present at night be present at night and at rest (late and at rest (late disease)disease)
Hand OsteoarthritisHand Osteoarthritis
Symptomatic Symptomatic hand hand osteoarthritis-osteoarthritis- 26% of women26% of women 13% of men aged 13% of men aged
over 70.over 70. Leads to reduced Leads to reduced
grip strength, grip strength, difficulty writing, difficulty writing, and carrying and carrying weight.weight.
MultifactorialMultifactorial Genetic Genetic
predispositionpredisposition Mechanical Mechanical
FactorsFactors ObesityObesity Prior Prior
inflammatory inflammatory joint diseasejoint disease
Zhang Y et al. Am J Epidemiol 2002; 156:1021-1027.
Risk Factors for OARisk Factors for OA
Vulnerable Joint
Genetic PredispositionAge
GenderEthnicity
Dietary Factors
MalalignmentStructural abnormality (BML, meniscal tear, ACL)
Bridging Muscle WeaknessProprioceptive Deficiencies
Laxity
ObesityObesity
Increased BMI has been associated with Increased BMI has been associated with an increased prevalence of knee, hip, an increased prevalence of knee, hip, and hand OA .and hand OA .
Weight loss of 5kg is associated with a Weight loss of 5kg is associated with a 50% reduction in chance of developing 50% reduction in chance of developing OA, and also slows progression.OA, and also slows progression.Adjusted OR (95% CI)
Risk Factor Male Female
Age (per 5-year) 0.9 (0.5-1.6) 1.3 (0.9-1.7)
BMI (per 5-unit) 1.0 (0.5-2.1) 1.8 (1.2-2.6)
Weight change (per 10-lb) 0.9 (0.5-1.5) 1.6 (1.2-2.3)
Aims of ManagementAims of Management
Patient education about both the disease Patient education about both the disease and its management and its management
Pain controlPain control Improvement of function Improvement of function Alteration of the disease process and its Alteration of the disease process and its
consequencesconsequences
Algorithm for OA Algorithm for OA ManagementManagement
Knee MRIKnee MRI
Relation of MRI Relation of MRI features to features to symptoms.symptoms.
Improvement of Improvement of scoring methods.scoring methods.
Clinical TrialsClinical Trials
Outcome Outcome measurement- measurement- function and function and structurestructure
Responsiveness Responsiveness of cartilage of cartilage volume, volume, dGEMRIC, dGEMRIC, biomarkers.biomarkers.
Knee Brace ± Knee Brace ± Orthosis.Orthosis.
0.2
0.4
1.0
0.8
0.6
T1 (sec)
1.2
Relationship between peri-articularbone changes and initiation and progression of OA
CHICKEN(bone)
EGG(cartilage)
WHICH COMES FIRST?
Intervention-PF Bracing Intervention-PF Bracing TrialTrial
CONTROL ARM CONTROL ARM Q Brace without Q Brace without
T strap.T strap. ACTIVEACTIVE
Stratus Q Brace .Stratus Q Brace .
Thank-you for your Thank-you for your attentionattention
Raphael. The School of Athens