Rheumatology/MSK Flashcards
(204 cards)
Define osteoarthritis
Non inflammatory, progressive synovial joint damage caused by wear and tear of most commonly used joints.
Joints commonly affected in osteoarthritis
Knees
Hips
Sarco-ileac joints
Wrist
Carpometacarpal
Interphalangeal
Risk factors for osteoarthritis
Age
Female sex
Raised BMI/obesity
Joint injury/trauma
Joint malalignment (congenital or not)
Pathophysiology of osteoarthritis
Usually, cartilage breakdown and production by chondrocytes is under balance.
In OA, chondrocytes secrete more metalloproteinases (degrading enzymes) leading to loss of Type 2 cartilage. (Type 1 has less elasticity)
IL-1 and TNF-a also stimulate metalloproteinase production and inhibit collagen production.
Causes decreased joint space, which causes damage to bones on movement. Bone attempts to repair itself with type 1 collagen but causes bony overgrowths
Signs/symptoms of osteoarthritis
Asymmetrical non inflamed joint pain, which gets worse as the day goes on
- Herbeden’s nodes (DIP Swelling)
- Bouchard’s nodes (PIP swelling)
- Fixed flexion deformity of carpometacarpal
- Joint pain worse with activity
- Mechanical locking
- Joint stiffess, tenderness, crepitus (crunching sensation when moving)
- NO EXTRA ARTICULAR MANIFESTATIONS
Typical presentation of osteoarthritis
> 45 years old
Typical activity related pain
No morning stiffness (<30 mins)
Investigations in osteoarthritis
1st - X ray (LOSS)
L - Loss of joint space
O - Osteophytes (bony overgrowths)
S - Subchondral sclerosis
S - Subchondral cysts
Non pharmacological treatments of osteoarthritis
- Weight loss
- Low impact exercise
- Physiotherapy
- Occupational therapy
- Heat/cold packs at site of pain
- Orthotics (helps with foot issues)
Pharmacological treatment of osteoarthritis
1st - Oral paracetamol, topical capsaicin, topical NSAID
Topical NSAID first for knee
Others:
- Intra articular steroid injection
- Joint replacement
Define Rheumatoid arthritis with epidemiology
Autoimmune, systemic disease causing symmetrical deforming inflammation of small joints which progresses to larger joints and organs.
More in women aged 30-50
Type 3 hypersensitivity reaction
Risk factors for Rheumatoid arthritis
- Female
- Smoking
- Family history
- Post menopause
- HLA-DR1, HLA-DR4
Pathophysiology of rheumatoid arthritis
Arginine -> Citrulline mutation of type 2 collagen. Immune cells cannot differentiate self and non-self, causing antibody formation. Anti-CCP (cyclic citrullinated peptide) antibodies formed. These bind to citrullinated peptides and form immune complexes, which accumulate in synovial fluid, causing inflammation.
Cytokines recruited by macrophages (TNF, IL1,6) proliferate, forming thick pannus containing cytokines, myofibroblasts and fibroblasts. These grow past joint margins, destroy subchondral bone and articular cartilage. T cells also express RANKL, which bind to osteoclasts, causing bone breakdown.
Inflammatory cytokines also escape joint space, causing systemic effects
Signs/symptoms of rheumatoid arthritis
Symmetrical polyarthritis
Signs
- Boutonniere deformity (PIP flexion, DIP hyperextension)
- Swan-neck deformity (PIP hyperextension, DIP flexion)
- Z thumb deformity (thumb IP hyperextension, MCP flexion)
- Ulnar deviation
- Popliteal cysts (synovial sac bulges posterior to knee)
- Rheumatoid nodules (lumps under skin and around organs)
Symptoms
- Morning stiffness, >30 mins, improves throughout day
- Carpometacarpal joint spared in rheumatoid but not psoriatic
Investigations in rheumatoid arthritis
ESR/CRP high
Autoantibodies:
- Anti CCP (more specific - can be detected 15 years before symptoms)
- Rheumatoid factor (present in other diseases e.g. Sjogren’s)
X ray- LBSP
Loss of joint space
Bone erosions
Soft tissue swelling
Periarticular osteopenia (punched out erosion)
Subluxation
Extra articular manifestations of rheumatoid arthritis
(skin, respiratory, CVD, eyes, haem, systemic)
Skin
- Rheumatoid nodules
Respiratory
- Pulmonary nodules
- Pleurisy
- Bronchiectasis
- Caplan’s syndrome
- Interstitial lung disease
Opthalmological
- Keratoconjunctivitis sicca
- Scleritis
- Corneal ulceration
CVD
- IHD and pericarditis
Anaemia, Amyloidosis, Felty syndrome
Treatment of rheumatoid arthritis
DMARD - Methotrexate (CI in pregnancy!)
NSAID
Intraarticular steroid injections
Main life threatening complication of rheumatoid arthritis
Felty’s syndrome
- Rheumatoid arthritis
- Splenomegaly
- Neutropenia
Monitoring of rheumatoid arthritis
Monitor FBC, LFT, U&E weekly until treatment stabilised
Check ESR/CRP monthly
- Check disease activity score (DAS-28) annually
- Check for comorbidities
- Assess for surgery need
What type of reaction is rheumatoid arthritis
Type 3 hypersensitivity
Define gout
Inflammatory Arthritis caused by deposition of monosodium urate crystals in joints (Most commonly first metatarsophalangeal (MTP) joint - big toe)
Risk factors for gout
- Elderly
- Male
- Purine rich foods (red meat, seafood, alcohol)
- Obesity
- Hypertension
- Impaired kidney function
- Type 2 diabetes mellitus
- Family history
Causes of gout
Increased uric acid production
- Increased cell turnover (leukaemia, haemolytic anaemia)
- Purine rich diet (shellfish, red meat, organ meat)
- Obesity/metabolic syndrome
Decreased excretion
- CKD
- Diuretics/aspirin/pyrazinamide
- Lead toxicity
What type of diet would you recommend a patient with gout switch to
High dairy diet is protective from Gout
Pathophysiology of gout
Normally, purines are broken down into uric acid by xanthine oxidase, which is then excreted by kidney. Uric acid has limited solubility in blood, in high concentrations, can become a urate ion which binds to sodium to become monosodium urate, which deposits in areas of low blood flow (joints/ kidney tubules).
WBCs attack said crystals, causing inflammation