125 - Osteoarthritis Flashcards
If someone has joint pain, how could you describe it in one word?
Arthralgia
Is someone has joint inflammation, how would you describe it in one word?
Arthritis
Is someone has a joint deformation, how could you describe it in one word?
Arthropathy
How could you determine between inflammatory joint pain and mechanical joint pain?
Inflammatory: gets better with use. Has diurnal pattern. Early morning stiffness. Swelling Red + Hot
Mechanical - worse after use
Most painful at end of day
What are the different dirstributions of inflammatory joint pain?
Monoarthritis - one joint
Olgioarthritis - a few joints
Polyarthritis - many joints
What is an example of monoarthritis?
Septic arthritis
Reactive arthritis
Gout
Isolated OA
What are examples of oligoarthritis?
Reactive arthritis
Psoriatic arthritis
OA
Ankylosing spondylitis
What can cause polyarthritis?
OA
RA
Gout
When considering joint pain, what must you be aware it could also be?
Periarticular joint pain - eg. in the close muscles, tendons, synovial fluid..
What non inflammatory joint disorders are there?
Metabolic - eg. osteromalacia, vit D deficiency, throid issues
Mechanical/degenerative
Fibromyalgia
What factors help maintain the stability of a joint?
Bones
Ligaments
Muscles
What is OA?
Osteoarthritis
Most common joint disorder
Degeneration of joint cartillage and the underlying bone - chronic degenerative process.
What increases the risk for OA?
Local biomechanical factors - joint weakness, joint congruency, high impact loading
What are OA risk factors?
Hereditary
Obestiy
Hypermobility
Smoking
Where is OA most common?
Hands - especially DIP and PIP joints
Knee - 75% medial sided
Feet
Hips
What clinical signs are expected in OA?
Joint pain Joint tenderness Limited movement Crepitus Occasional effusion
What pathological changes are seen in OA?
focal destruction of cartilage
Sclerosis of subchondral bone
Subchondral cysts
Marginal ostephytes
- due to a metabolically active repair process - triggered by a variety of joint insults
What investigations would you suggest for someone with suspected OA?
Bloods - CRP, ESR
Synovial fluid aspiration
X ray
What is synovial fluid normally like?
Clear, colourless, oil like
What might you see on a standing up knee X ray in someone with OA?
L oss of joint space
O steophytes
S ubchondral sclerosis
S ubchondral cysts
What is the non-pharmacological management of OA?
Info - use the joint
Weight loss
Exercise
Physio help - adaptive devices, supportive devices
What pharmacological management is seen in OA?
Topical - NSAIDS, capsaicin
Systemic - Paracetamol, NSAIDS, Opiods
Intra-articular - Corticosteroids, Hyaluronate (acts like fake synovial fluid)
If pharmacological methods fail in OA what is left for patients to try?
Surgery - Joint preserving, eg. arthroscopic debridement, osteotomy (realignment of the joint)
- Joint replacement - Arthroplasty
What is the future in terms of OA management?
Joitn modifying agents
- Glucosamine was used, but limited evidence of repair benefit
- Stem call transplants
What is Wolff’s law of biomechanics?
The shape and structure of a bone (and all MSK tissue) is a reflection of their mechanical loading history.
What are the 5 types of force a bone can be subjected to?
Tension Compression Torsion Sheer Bending
What fractures are seen after a tension force is exerted?
Avultion fractures - bits of bone pulled away where the tendon joins
What fractures are seen after compressive forces are applied?
Vertebral fractures - particularly in osteoporosis
What type of damage is caused by sheer forces?
Spondylolisthesis - 2 vertebrae are forced to slide over one another.
What is the typical force caused by bending fractures?
Ski boot fractures
What type of fracture is common from a torsion force?
Spiral fractures of the femur
What are the bio-mechanical adaptations of cartilage?
Adapted to withhold compressive and sheer forces
What are the bio-mechanical adaptations of tendons?
have high type 1 collage levels - so can resist tensile forces.
Act as springs in locomotion - store energy when stretched and released to complement muscle action
What are the bio-mechanical adaptations of menisci?
Fibrocartillagenous - key to help load distribution.
50% of the compressive load of the knee is through the medial meniscus
What are the bio-mechanical adaptations of ligaments?
Their stiffness can change - initially work in a low force range during normal movements, as force increases, ligaments become stiffer to protect the joint more
They link bones across joints, the guide joints and limit them.
They act as strain sensors.
What are the 4 key biomechanical properties of muscle?
Irritability
Contractility
Extensibility
Elasticity
What enables a muscle to have elasticity?
Titin
What influences muscle movements?
Gravity
What are the 4 classes of muscle actions?
Agonist
Antagonist
Fixator/stabiliser
synergist
What does a fixator/stabiliser muscle do?
Provides an immobile base for a joint, on which an antagonist/prime mover can act.
What does a synergist muscle do?
Prevents unwanted movements, which would be produced if the agonist acted solo.
What are the 4 ways the skeletal movement is limited?
Passive insufficiency
Active insufficiency
Concurrent movement
Countercurrent movement
Describe passive insufficincy
In bi-articular muscles, which cross 2 joints, you can’t move both joints simultaneously
Describe active insuffieicney
There is a limit on hw much a muscle can contract - limiting the amount of movement possible
Describe concurrent movement
When, for example, there is simultaneous flexion or extension of both the knee and the hip
Describe countercurrent movement
When one muscle shortens at both joints, and its antagonist lengthens correspondingly, so tension is gained at both ends.
What does the swing component of a muscle action do?
It moves or alters the angle of the mobile bone - eg. brachialis flexes the elbow
What does the shunt component of a muscle action do?
It compresses bones together - eg. brachioradialis
What does the spin component of a muscle action do?
It twists or rotates the bone along its long axis- eg. Supinator
What is gait?
The manner and style of an individuals walk
What occurs in stance phase?
65% of the gait cycle
From heel strike to toe off
Loading resposne, mid stance, terminal stance
What occurs in swing phase?
From toe off to heel strike
Preswing - midswing - terminal swing
Single leg support
35% of cycle
What is wolff’s law of bone?
The structure/shape of the bone changes depending on the mechanical loading of the bone. - all MSK tissue
What forces is bone subjected to?
Tension - pullSheer - snappingCompression Bending Torsion - twisting/spiral
Describe Menisci
fibrocartillagenousHelp load distribution - 50% of compressive load of knee through the medial meniscus.Increases joint contact area
What helps tendons resist tensile forces?
Collagen I
What are the 4 biomechanics properties of muscle?
Irritability - responds to nervesContractibilityExtensibilityElasticitiy
What gives muscle it’s elastic properties?
Titin
What are 4 types of muscle action?
Agonist - prime mover - main muscle of a jointAntagonist - Opposes the agonist - brings joint backFixator/stabiliser - provides immobile base so other rime movers can actSynergist - Prevents unwanted movements
How do muscles help limit skeletal movement?
Passive insufficiency - biarticular muscles - can’t move both joints at once.Active insufficiency - Muscle can’t contract more than a fixed amountConcurrent movement - another muscle moves to aid the function of another. Countercurrent movement
What is Osteroarthritis?
Joint failure - cartillage diseaseMost common joint disorderHeterogenous. Multiple interactions.Chronic degenerative condition - not just ageing
What are the risk factors of OA?
HereditaryObesityHyper mobilitySmokingLocal biomechanics factors
What clinical signs suggest OA?
Joint pain - mechanical - gets worse with useJoint tendernessLimited movementCrepitusOccasional effusion
What investigations can you do for OA?
No set test - bloods will be normal (it doesn’t have much inflammation)- Xray- Synovial fluid usually clear
