MSK Diseases 1 Flashcards
What is OA?
osteoarthiritis
DEGENERATIVE JOINT DISEASE
Patho of OA?
Wear and Tear leads to destroying the T2 collagen and proteoglycans
Chondrocytes will try and rescue by producing T2 collagen and proteoglycans
But after a while it does not work, and instead they start producing type 1 collagen.
T1 collagen and proteoglycans don’t interact and hence the joint loses elasticity
After a while, the chondrocytes cant keep up and undergo apoptosis causing cartilage to flake off and float in the synovial cavity
These flaky segments invite macrophages and pro-inflammatory cytokines to join the party – and they bring their cleaning booze with them
This leads to synovitis and fibrillation aka cracks – these cracks continue to erode – until just bone is remaining.
This bone on bone movement is called eburnation, and makes the bones look like polished ivory. Later this leads to bone stretching laterally producing osteophytes
Classification of OA
Primary where aetilogy is unknown and Secondary where aetilogy is known
In primary the joint has worn out Naturally, age related, normal wear and tear (Genetic, biochemical, Mechanical, Age-related)
Most people after 60 will have some percentage of OA
Secondary: Trauma, Neuropathic Joint disease, Other inflammatory joint disease, previous repeated steroid injections.
WHat is the grading for OA?
Commonly affected joints in OA
- Hips
- Knees
- Sacro-iliac joints
- Distal-interphalangeal joints in the hands (DIPs)
- The CMC joint at the base of the thumb
- Wrist
- Cervical spine
WHat are the four radiological signs seen in OA
What are OA changes in the joints
What are the risk factors for OA?
- AGE is THE BIGGEST RF
- Inflammation increases the progression of OA (some of the factors cause proteolysis and some factors block formation of new cart) : which is usually caused after JOINT INJURY
- Mechanical stress and OBESITY
- Genetics
- Meds
- Neuro Disorders
- Ocuupation
- Female
What are the Important Features seen in OA
Usually bilateral: Usually one joint at a time is affected over a period of several years. The carpometacarpal joints, distal interphalangeal joints are affected more than the proximal interphalangeal joints.
Episodic joint pain: An intermittent ache. Provoked by movement and relieved by resting the joint.
Stiffness: Worse after long periods of inactivity e.g. waking up in the morning. Stiffness lasts only a few minutes compared to the morning joint stiffness seen in rheumatoid arthritis.
Painless nodes (bony swellings): Heberden’s nodes at the DIPJs, Bouchard’s Nodes at the PIPJs. These nodes are the result of osteophyte formation
What are the signs you look for in hands for OA
Herberdens node
Bouchards node
Squaring of the thumbs: Deformity of the carpometacarpal joint of the thumb resulting in fixed adduction of the thumb.
What is this seen in?
OA
How is osteoarthritis different to inflammatory arthritis?
Osteoarthritis presents with joint pain and stiffness. This pain and stiffness tends to be worsened by activity in contrast to inflammatory arthritis where activity improves symptoms. It also leads to deformity, instability and reduced function in the joint.
Treatment for OA
patient education: weightloss, physio, OT
Medical / Conservative
- Oral paracetamol and topical NSAIDs or topical capsaicin (chilli pepper extract).
- Add oral NSAIDs and consider also prescribing a proton pump inhibitor (PPI) to protect their stomach such as omeprazole. They are better used intermittently rather than continuously.
- Consider opiates such as codeine and morphine. These should be used cautiously as they can have significant side effects and patients can develop dependence and withdrawal. They also don’t work for chronic pain and result in patients becoming depending without benefitting from pain relief.
Surgical
- Intra-articular steroid injections provide a temporary reduction in inflammation and improve symptoms.
- Replacement
What is Gout
Inflammatory disease in which monosodium urate crystals deposit into a joint making it red, hot, tender and swollen within hours
Crystals usually develop in areas of fast blood flow like the joints and liver
TRUE OR FALSE
FALSE
Crystals usually develop in areas of slow blood flow like the joints and kidney tubules.
What is uric acid present in?
Uric acid is present in Purines, Foods - shellfish, anchovies, red and organ meat.
WHat joint is affected in gout usually?
1st metatarsal joint is usually affected, its called podagra. person will wake up from sleep, and will feel as if their big toe is on fire.
- Base of the big toe (metatarsophalangeal joint)
- Wrists
- Base of thumb (carpometacarpal joints)
In gout you might find the presence of _____: White, Chalky aggregates of uric acid crystals with fibrosis and giant cell reaction in soft tissues and joints aka permanent deposits of uric acid crystals.
In gout you might find the presence of Tophi: White, Chalky aggregates of uric acid crystals with fibrosis and giant cell reaction in soft tissues and joints aka permanent deposits of uric acid crystals.
Risk factors for gout
Male
Obesity
High purine diet (e.g. meat and seafood)
Alcohol
Diuretics
Existing cardiovascular or kidney disease
Family history
Prophylaxis of Gout
Allopurinol is a xanthine oxidase inhibitor used for the prophylaxis of gout. It reduces the uric acid level.
Lifestyle changes can reduce the risk of developing gout. This involves losing weight, staying hydrated and minimising the consumption of alcohol and purine-based food (such as meat and seafood).
TOM TIP: Do not initiate allopurinol prophylaxis until after the acute attack is settled. Once treatment of allopurinol has been started then it can be continued during an acute attack.
Radiological features for gout?
- Joint effusion is an early sign
- Well defined punched out erosions
- Relative presentation of joint space until late disease
- Eccentric (well defined) erosions
- No particular osteopenia (in contrast with RA)
- Soft tissue tophi many be seen
What Can lead to GOUT?
Decreased Uric Acid Excretion
- drugs: diuretics
- chronic kidney disease
- lead toxicity
Increased production of uric acid
- myeloproliferative/lymphoproliferative disorder
- cytotoxic drugs
- severe psoriasis
How do you diagnose Gout?
History and Exam
Serum Urate - may be normal during an attack
Joint aspiration - synovial fluid will show negatively bi-fringent needle shaped crystals under polarized light
Management of Gout
During the acute flare:
- NSAIDs (e.g. ibuprofen) are first-line
- Colchicine second-line
- Steroids can be considered third-line
Colchicine is used in patients that are inappropriate for NSAIDs, such as those with renal impairment or significant heart disease. A notable side effect is gastrointestinal upset. Diarrhoea is a very common side effect. This is dose-dependent meaning lower doses cause less upset than higher doses.
