Ortho II Flashcards
What is most common type of primary malignant bone tumour
Osteosarcoma
Which most population are more affected by osteosarcomas
Children and adolescents
where do osteosarcomas mostly commonly occur
occurs most frequently in the metaphyseal region of long bones prior to epiphyseal closure, with 40% occuring in the femur, 20% in the tibia, and 10% in the humerus
What might an x-ray show in osteosarcoma
x-ray shows Codman triangle (from periosteal elevation) and ‘sunburst’ pattern
What mutation is associated with osteosarcoma
mutation of the Rb gene significantly increases risk of osteosarcoma (hence association with retinoblastoma)
other predisposing factors include Paget’s disease of the bone and radiotherapy
Definition of osteoporosis
presence of bone mineral density (BMD) of less than 2.5 standard deviations (SD) below the young adult mean density.
Risk factors for osteoporosis
Age Female gender Corticosteroid use Smoking Alcohol Low BMI Family Hx
Recommended screening tool for assessing fracture risk in osteoporosis
Guidelines recommend using a screening tool such as FRAX or QFracture to assess the 10-year risk of a patient developing a fragility fracture.
How is bone mineral density assessed
To assess the actual bone mineral density a dual-energy X-ray absorptiometry (DEXA) scan is used. The DEXA scan looks at the hip and lumbar spine. If either have a T score of < -2.5 then treatment is recommended.
1st line treatment for osteoporosis
Oral bisphosphonate such as alendronate
How do patients with osteoporotic vertebral fractures typically present
Asymptomatic
Acute back pain
Breathing difficulties: changes in the shape and length of vertebrae lead to the compression of organs such as the lungs, heart and intestine
Gastrointestinal problems: due to compression of abdominal organs
Only a minority of patients will have a history of fall/trauma
Signs of osteoporotic vertebral fractures
Loss of height: vertebral osteoporotic fractures of lead to compression of the spinal vertebrae hence a reduction in overall length of the spine and thus the patient becomes shorter
Kyphosis (curvature of the spine)
Localised tenderness on palpation of spinous processes at the fracture site
Advice for supplementation for women with osteoporosis
vitamin D and calcium supplementation should be offered to all women unless the clinician is confident they have adequate calcium intake and are vitamin D replete
Alternative if patients cannot tolerate alendronate for osteoporosis mx
Around 25% of patients cannot tolerate alendronate, usually due to upper gastrointestinal problems. These patients should be offered risedronate or etidronate
Alternative if patients cannot tolerate bisphosphonates for osteoporosis management
Strontium ranelate and raloxifene are recommended if patients cannot tolerate bisphosphonates
What is raloxifene
Selective oestrogen receptor modulator(SERM)
has been shown to increase bone density in the spine and proximal femur
may worsen menopausal symptoms
increased risk of thromboembolic events
may decrease risk of breast cancer
Features of denosumab
human monoclonal antibody that inhibits RANK ligand, which in turn inhibits the maturation of osteoclasts
given as a single subcutaneous injection every 6 months
Assessing patients following a fragility fracture - Age>75
Patients who’ve had a fragility fracture and are >= 75 years of age are presumed to have underlying osteoporosis and should be started on first-line therapy (an oral bisphosphonate), without the need for a DEXA scan.
Assessing patient following a fragility fracture - Age<75
If a patient is under the age of 75 years a DEXA scan should be arranged. These results can then be entered into a FRAX assessment (along with the fact that they’ve had a fracture) to determine the patients ongoing fracture risk.
Management of glucocorticoid-induced osteoporosis
- Patients over the age of 65 years or those who’ve previously had a fragility fracture should be offered bone protection.
- Patients under the age of 65 years should be offered a bone density scan, with further management dependent
Normal DEXA scan T score
> -1.0 = normal
Interpretation of DEXA scan T score -1.0 to -2.5
Osteopenia
Interpretation of DEXA scan T score < -2.5
Osteoporosis
What is osteomalacia
Osteomalacia describes softening of the bones secondary to low vitamin D levels that in turn lead to decreased bone mineral content. If this occurs in growing children it is referred to as rickets, with the term osteomalacia preferred for adults.
Causes of osteomalacia
vitamin D deficiency malabsorption lack of sunlight diet chronic kidney disease drug induced e.g. anticonvulsants inherited: hypophosphatemic rickets (previously called vitamin D-resistant rickets) liver disease: e.g. cirrhosis
Features of osteomalacia
bone pain
bone/muscle tenderness
fractures: especially femoral neck
proximal myopathy: may lead to a waddling gait
IX for osteomalacia
Bloods
low vitamin D levels
low calcium, phosphate (in around 30%)
raised alkaline phosphatase (in 95-100% of patients)
x-ray translucent bands (Looser's zones or pseudofractures)
Treatment for osteomalacia
vitamin D supplmentation
a loading dose is often needed initially
calcium supplementation if dietary calcium is inadequate
Most common side effects of denosumab
Dyspnoea and diarrhoea are generally considered the two most common side effects, occuring in around 1 in 10 patients. Other less common side effects include hypocalcaemia and upper respiratory tract infections.
Bisphosphonates mechanism of action
Bisphosphonates are analogues of pyrophosphate, a molecule which decreases demineralisation in bone. They inhibit osteoclasts by reducing recruitment and promoting apoptosis.
Clinical uses of bisphosphonatees
prevention and treatment of osteoporosis
hypercalcaemia
Paget’s disease
pain from bone metatases
Adverse effects of bisphosphonates
oesophageal reactions: oesophagitis, oesophageal ulcers (especially alendronate)
osteonecrosis of the jaw
increased risk of atypical stress fractures of the proximal femoral shaft in patients taking alendronate
BNF advice for counselling for bisphosphonates
Tablets should be swallowed whole with plenty of water while sitting or standing; to be given on an empty stomach at least 30 minutes before breakfast (or another oral medication); patient should stand or sit upright for at least 30 minutes after taking tablet
What is osteopenia
Osteopenia refers to a less severe reduction in bone density than osteoporosis. Reduced bone density makes bone less strong and more prone to fractures.
Features of strontium ranelate
Strontium ranelate is a similar element to calcium that stimulates osteoblasts and blocks osteoclasts but increases the risk of DVT, PE and myocardial infarction.
Risk factors for osteoarthritis
Risk factors include obesity, age, occupation, trauma, being female and family history.
What is osteoarthritis thought to be linked to
It is thought to be the result of an imbalance between the cartilage being worn down and the chondrocytes repairing it leading to structural issues in the joint.
X-ray abnormalities of osteoarthritis
L – Loss of joint space
O – Osteophytes
S – Subchondral sclerosis (increased density of the bone along the joint line)
S – Subchondral cysts (fluid-filled holes in the bone, aka geodes)
Osteoarthritis presentation
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.
Commonly affected joints in osteoarthritis
Hips Knees Sacro-iliac joints Distal-interphalangeal joints in the hands (DIPs) The MCP joint at the base of the thumb Wrist Cervical spine
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 at the carpo-metacarpal joint Weak grip Reduced range of motion
General management of osteoarthritis
Start with patient education about the condition and advise on lifestyle changes such as weight loss if overweight to reduce the load on the joint, physiotherapy to improve strength to support the joint and occupational therapy and orthotics to support activities and function.
Analgesia in osteoarthritis
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.
Intra-articular steroid injections provide a temporary reduction in inflammation and improve symptoms.
Causes of mechanical back pain
Muscle or ligament sprain
Facet joint dysfunction
Sacroiliac joint dysfunction
Herniated disc
Spondylolisthesis (anterior displacement of a vertebra out of line with the one below)
Scoliosis (curved spine)
Degenerative changes (arthritis) affecting the discs and facet joints
Causes of neck pain
Muscle or ligament strain (e.g., poor posture or repetitive activities)
Torticollis (waking up with a unilaterally stiff and painful neck due to muscle spasm)
Whiplash (typically after a road traffic accident)
Cervical spondylosis (degenerative changes to the vertebrae)
Red-flag causes of back pain
Spinal fracture (e.g., major trauma) Cauda equina (e.g., saddle anaesthesia, urinary retention, incontinence or bilateral neurological signs) Spinal stenosis (e.g., intermittent neurogenic claudication) Ankylosing spondylitis (e.g., age under 40, gradual onset, morning stiffness or night-time pain) Spinal infection (e.g., fever or a history of IV drug use)
Causes of back pain not linked to spine
Pneumonia Ruptured aortic aneurysms Kidney stones Pyelonephritis Pancreatitis Prostatitis Pelvic inflammatory disease Endometriosis
Spinal nerve roots for the sciatic nerve
L4-S3
Path of the sciatic nerve
The sciatic nerve exits the posterior part of the pelvis through the greater sciatic foramen, in the buttock area on either side. It travels down the back of the leg. At the knee, it divides into the tibial nerve and the common peroneal nerve.
What does the sciatic nerve innervate
The sciatic nerve supplies sensation to the lateral lower leg and the foot. It supplies motor function to the posterior thigh, lower leg and foot.
Presentation of sciatica
Unilateral pain from the buttock radiating down the back of the thigh to below the knee or feet.
It might be described as an “electric” or “shooting” pain. Other symptoms are paraesthesia (pins and needles), numbness and motor weakness.
Reflexes may be affected depending on the affected nerve root.
Main causes of sciatica
The main causes of sciatica are lumbosacral nerve root compression by:
Herniated disc
Spondylolisthesis (anterior displacement of a vertebra out of line with the one below)
Spinal stenosis
What is bilateral sciatica a red flag for
cauda equina syndrome
Which symptoms associated with back pain indicate cauda equina syndrome
Saddle anaesthesia
Urinary retention or incontinence
Faecal incontinence
Bilateral neurological motor or sensory symptoms
What is the sciatic stretch test
can be used to help diagnose sciatica. The patient lies on their back with their leg straight.
The examiner lifts one leg from the ankle with the knee extended until the limit of hip flexion is reached (usually around 80-90 degrees). Then the examiner dorsiflexes the patient’s ankle.
Sciatica-type pain in the buttock/posterior thigh indicates sciatic nerve root irritation. Symptoms improve with flexing the knee.
main cancers that metastasise to the bones
Po – Prostate R – Renal Ta – Thyroid B – Breast Le – Lung
(portable)
ix for ankylosing spondylitis
Inflammatory markers (CRP and ESR)
X-ray of the spinal and sacrum (may show a fused “bamboo spine” in later-stage disease)
MRI of the spine (may show bone marrow oedema early in the disease)
Which tool can be used to risk stratify patients with acute back pain
STarT back screening tool - risk of developing chronic back pain
Management of patients with low risk of chronic back pain
Self-management Education Reassurance Analgesia Staying active and continuing to mobilise as tolerated
Management of patients with medium/high risk of developing chronic back pain
Physiotherapy
Group exercise
Cognitive behavioural therapy
Analgesia options for back pain
NSAIDs (e.g., ibuprofen or naproxen) first-line
Codeine as an alternative
Benzodiazepines (e.g., diazepam) for muscle spasm (short-term only – up to 5 days)
What is radio frequency denervation
Radiofrequency denervation may be an option in patients with chronic low back pain originating in the facet joints. Radiofrequency is used to target and damage the medial branch nerves that supply sensation to the facet joints associated with the back pain. This is done under a local anaesthetic.
Pharmacological interventions for sciatica if persisting symptoms
Amitriptyline
Duloxetine
Specialist management options for chronic sciatica
Epidural corticosteroid injections
Local anaesthetic injections
Radiofrequency denervation
Spinal decompression
Conservative mx of carpal tunnel syndrome
Wrist splints
Corticosteroids
Rest
Surgical mx of carpal tunnel syndrome
Arthroscopy
Most common distal radial fracture
Colle’s fracture - extra-articular fracture with dorsal angulation and displacement - dinner fork
