Breaking is bad Flashcards
What is Osteoporosis?
Osteoporosis is a complex skeletal disease characterised by low bone density and micro-architectural defects in bone tissue, resulting in increased bone fragility and susceptibility to fracture.
What is bone density determined by?
Bone mineral density Size/shape of the bone Bone turnover Micro-architecture Bone mineralisation
What are the risk factors for fractures?
Prior fragility fracture
Female sex (they have lower peak bone mass + have greater declines in bone mass over time
White ancestry
Older age (over 50 for women, over 65 for men).
Low BMI (loss of bone mass is accelerated in those with a lower BMI)
Fam hx of maternal hip fracture
Loss of height (may indicate vertebral fracture)
Post-menopause (oestrogen decline - decreases in bone mineral density).
Prolonged immobilisation (bone mineral density declines).
Vitamin D deficiency (associated with increased PTH production -> increased bone resorption).
Smoking + excessive alcohol intake (bone mass declines more rapidly + increases risk of osteoporosis).
Glucocorticoid excess (50% of people with Cushing’s syndrome experience fractures (esp vertebral)).
What is a DXA scan?
Dual-energy x-ray absorptiometry (DXA). DXA scans measure bone density. The result is given in a T-score which is determined by measuring bone density at the hip. This means they are best at predicting hip fractures. A T-score of < or equal to 2.5 is indicative of osteoporosis. A T-score of < or equal to 2.5 with fragility fractures = indicative of severe or established osteoporosis.
What are the diagnostic tests for osteoporosis?
Dual-energy x-ray absorptiometry
Quantitative ultrasound of the heel
X-rays (heel, wrist, spine, hip)
How would you manage a female patient with high risk of osteoporotic fracture?
Give them bisphosphonate (alendronate) and consider prescribing calcium and vitamin D supplementation too.
If bisphosphonates are contraindicated/not tolerated, then - teriparatide and calcium and vitamin D supplementation.
How would you manage a male patient with osteoporosis and low testerone?
Testosterone added to bisphosphonate (testosterone buccal) + calcium and vitamin D supplementation.
Who should be risk assessed for fragility fractures?
All women aged 65+ and all men aged 75+.
In women aged below 65 and men aged below 75 if they have the relevant risk factors.
What tools can be used to assess risk of fracture?
you can use FRAX (fracture risk assessment tool) with or without BMD value (bone mineral density value) or QFracture to estimate 10-year predicted absolute fracture risk. FRAX - age range = 40-90, with or without BMD values. QFracture - age range = 30-84, BMD values can’t be factored in.
What is a fracture?
A fracture is a soft tissue with a loss of continuity in the bone and there can be different types of fractures depending on the mechanism of action and the place the break is.
What are the different types of fracture?
Stable fracture - the broken ends of the bone line up and are barely out of place.
Open compound fracture - skin may be pierced by the bone or by a blow that breaks the skin at the time of the fracture. The bone may or may not be visible in the wound.
Transverse fractures - a horizontal fracture line, an oblique fracture which a fracture in an angled pattern or a comminuted fracture which is where the bone shatters into 3 or more pieces.
What is a hip fracture?
Considered to be any fracture of the femur distal to the femoral head and proximal to a level a few centimetres below the lesser trochanter.
Neck of femur fractures are common injuries sustained by many older patients, who are more likely to have unsteadiness gait as well as reduced bone mineral density.
What causes hip fractures?
Hip fractures are mainly caused by falls from a standing height accounting for a significant majority of hip fractures in older people. This is associated with osteopenia or osteoporotic condition of bone.
In younger people, the primary aetiology is high energy trauma including motor vehicle accidents and falls from a height.
What is the mechanism behind hip fractures in elderly people?
With the elderly patients, the injury has multiple different mechanisms, varying from patients falling directly onto their hips to a twisting mechanism in which the patient’s foot is planted on the floor and the body rotates causing the hip to break.
What is the mechanism behind hip fractures in young people?
In younger patient the fracture is predominantly axial loading during high force trauma, with an abducted hip during injury causing a neck of femur fracture and an adducted hip causing a hip fracture dislocation.
What are the risk factors for hip fractures?
Falls Older age Osteoporosis/osteopenia Malignancy Female High energy trauma Medications Alcohol consumption
How might hip fractures present?
Global pains around the groin and the region on the greater trochanter, with this potentially radiating distally down the femur or up to the pelvis.
Pain is often increased with internal or external rotation of the leg or flexion of the hip.
Weight bearing is either impossible or causes pain in the groin, hip or femur.
How would you investigate hip fractures?
Plain X-rays
Full-length radiograph of the femur to identify bone metastasis
Bloods
MRI or CT scan
What aspects seen on X-ray would suggest a hip fracture?
Shenton’s line disruption: loss of contour between normally continuous line from medial edge of femoral neck and inferior edge of the superior pubic ramus
Lesser trochanter is more prominent due to external rotation of femur
Femur often positioned in flexion and external rotation
Asymmetry of lateral femoral neck/head
Sclerosis in fracture plane
Smudgy sclerosis from impaction
Bone trabeculae angulated
What is a intracapsular fracture?
Intracapsular fractures: The retinacular vessels that pass up the femoral capsule may be damaged, especially if the fracture is displaced, resulting in poor blood supply to the femoral head often leading to avascular necrosis.
What is an extracapsular fracture?
This includes intertrochanteric or subtrochanteric, which typically heal well.
What is the differential diagnosis for a hip fracture?
Acetabular fracture Pubic rami fracture Femoral shaft or subtrochanteric femur fracture Femoral head fracture Septic hip
What is the management for a hip fracture?
Pain relief
Non operative management
Internal fixation
Prosthetic replacement
What are the possible complications from a hip fracture?
Thromboembolic complications
Avascular necrosis
Non union/failure to fixation
What are ankle fractures?
Fractures types in which one or more of either the medial, lateral or posterior malleolus is broken.
Typically in young men and older females.
What causes ankle fractures?
Most commonly caused by a low energy fall, but other causes include inversion injury to the ankle, sporting injury, fall down the stairs, fall from a height and motor vehicle accident.
What are the risk factors for ankle fractures?
Osteoporosis and multiple falls
How might an ankle fracture present?
Swelling that is over the medial or lateral malleolus.
History of slip, fall or other trauma leading to inability to weight bear.
Pain is over the medial or lateral malleolus with associated with bruising.
May have heard a ‘pop’ on fall.
How would you investigate an ankle fracture?
X-ray
Use of Ottwa rules:
Bone tenderness at the posterior edge or tip of the lateral malleolus OR
Bone tenderness at the posterior edge or tip of the medial malleolus OR
Unable to weight bear or walk a few steps
What are the differential diagnosis for an ankle fracture?
Lateral ankle ligament tear
Achilles tendon rupture
