MSK Flashcards
(139 cards)
What is Osteoarthritis?
Osteoarthritis is often described as “wear and tear” in the joints. It occurs in the synovial joints and results from genetic factors, overuse and injury. Osteoarthritis is thought to result from an imbalance between cartilage damage and the chondrocyte response, leading to structural issues in the joint.
Commonly affected joints in osteoarthritis?
Hips
Knees
Distal interphalangeal (DIP) joints in the hands
Carpometacarpal (CMC) joint at the base of the thumb
Lumbar spine
Cervical spine (cervical spondylosis)
X ray changes seen in osteoarthritis
The four key x-ray changes in osteoarthritis can be remembered with the “LOSS” mnemonic:
L – Loss of joint space
O – Osteophytes (bone spurs)
S – Subarticular sclerosis (increased density of the bone along the joint line)
S – Subchondral cysts (fluid-filled holes in the bone)
X-ray reports might describe findings of osteoarthritis as degenerative changes. X-ray changes do not necessarily correlate with symptoms. A patient might have significant signs on an x-ray but minimal symptoms, or the reverse.
Presentation of osteoarthritis
Osteoarthritis presents with joint pain and stiffness. The pain and stiffness tend to worsen with activity and at the end of the day. This is the reverse of the pattern in inflammatory arthritis, where symptoms are worse in the morning and improve with activity. Osteoarthritis leads to deformity, instability and reduced function of the joint.
General signs of osteoarthritis are:
Bulky, bony enlargement of the joint
Restricted range of motion
Crepitus on movement
Effusions (fluid) around the joint
Signs of osteoarthritis in the hands
Heberden’s nodes (in the DIP joints)
Bouchard’s nodes (in the PIP joints)
Squaring at the base of the thumb (CMC joint)
Weak grip
Reduced range of motion The carpometacarpal joint at the base of the thumb is a saddle joint, with the metacarpal bone sitting on the trapezius bone, using it like a saddle. It gets a lot of use and is very prone to wear.
Dx of osteoarthritis
The NICE guidelines (2022) suggest that a diagnosis can be made without any investigations if the patient is over 45, has typical pain associated with activity and has no morning stiffness (or stiffness lasting under 30 minutes).
First line managament for osteoarthritis
Conservative management: Education and advice about their condition
Exercise: both muscle strengthening and general aerobic fitness
Weight loss (if overweight or obese)
Medical management
Non-pharmacological managament of osteoarthritis
Non-pharmacological management involves patient education and lifestyle changes, such as:
Therapeutic exercise to improve strength and function and reduce pain
Weight loss if overweight, to reduce the load on the joint
Occupational therapy to support activities and function (e.g., walking aids and adaptations to the home)
Stepwise management of osteoarthritis
First-line: topical non-steroidal anti-inflammatory drugs (NSAIDs)
Second-line: paracetamol and topical analgesia
Third-line: NSAID, paracetamol and topical capsaicin
Fourth-line: opioid, NSAID, paracetamol and topical capsaicin
Pharmacological management of osteoarthritis
Pharmacological management recommended by the NICE guidelines (2022) are:
Topical NSAIDs first-line for knee osteoarthritis
Oral NSAIDs where required and suitable (co-prescribed with a proton pump inhibitor for gastroprotection)
Weak opiates and paracetamol are only recommended for short-term, infrequent use. NICE (2022) recommend against using any strong opiates for osteoarthritis.
Intra-articular steroid injections may temporarily improve symptoms (NICE say up to 10 weeks).
Joint replacement may be used in severe cases. The hips and knees are the most commonly replaced joints.
Why do you have to be careful with NSAIDs with osteoarthritis tx?
NSAIDs (e.g., ibuprofen or naproxen) are very effective for musculoskeletal pain. However, they must be used cautiously, particularly in older patients and those on anticoagulants, such as aspirin or DOACs. They are best used intermittently, only for a short time during flares. They have several potential adverse effects, including:
Gastrointestinal side effects, such as gastritis and peptic ulcers (leading to upper gastrointestinal bleeding)
Renal side effects, such as acute kidney injury (e.g., acute tubular necrosis) and chronic kidney disease
Cardiovascular side effects, such as hypertension, heart failure, myocardial infarction and stroke
Exacerbating asthma
There is little evidence that opiates help with chronic pain. They are associated with side effects, risks, tolerance, dependence and withdrawal. They often result in dependence without any objective benefits.
Differentials for Osteoarthritis
Any joint: fracture, inflammatory arthropathies (such as rheumatoid arthritis), crystal arthropathies (such as gout), septic arthritis or malignancy
Knee: meniscal or ligamentous tears
Hip: bursitis, avascular necrosis
Hand: De Quervain’s tenosynovitis
What can be offered for the acute exacerbation of pain in osteoarthritis?
Intra-articular corticosteroid injection can be offered for acute exacerbation of pain despite regular use of the above analgesia. Typically, these are performed in an outpatient clinic environment. The injection consists of both a steroid and local anaesthetic, the latter providing immediate symptomatic relief to the patient for the first few hours. Patients may experience a worsening of symptoms for the first few days after administration, this is known as the ‘steroid flare’.
What is osteoporosis?
Osteoporosis involves a significant reduction in bone density.
What is osteopenia?
Osteopenia refers to a less severe decrease in bone density. Reduced bone density makes the bones weaker and prone to fractures.
What is the T score?
The World Health Organization (WHO) provide definitions based on the T-score of the femoral neck, measured on a DEXA scan. The T-score is the number of standard deviations the patient is from an average healthy young adult. A T-score of -1 means the bone mineral density is 1 standard deviation below the average for healthy young adults.
T score >-1
Normal
T score -1 to -2.5
Osteopenia.
T score < -2.5
Osteoporosis.
T score < -2.5 + fracture
Severe osteroporosis
How is Bone Mineral Density measured
Bone mineral density (BMD) is measured using a DEXA scan (dual-energy x-ray absorptiometry). DEXA scans are a type of x-ray that measures how much radiation is absorbed by the bones, indicating how dense the bone is. The bone mineral density can be measured anywhere on the skeleton, but the femoral neck reading is most important.
Bone density can be represented as a Z-score or T-score.
What is the Z score
The Z-score is the number of standard deviations the patient is from the average for their age, sex and ethnicity
Risk factors for osteoporosis
Older age
Post-menopausal women
Reduced mobility and activity
Low BMI (under 19 kg/m2)
Low calcium or vitamin D intake
Alcohol and smoking
Personal or family history of fractures
Chronic diseases (e.g., chronic kidney disease, hyperthyroidism and rheumatoid arthritis)
Long-term corticosteroids (e.g., 7.5mg or more of prednisolone daily for longer than 3 months)
Certain medications (e.g., SSRIs, PPIs, anti-epileptics and anti-oestrogens)
The NICE clinical knowledge summaries (April 2023) recommend assessing for osteoporosis in who?
Anyone on long-term oral corticosteroids or with a previous fragility fracture
Anyone 50 and over with risk factors
All women 65 and over
All men 75 and over