Hip and Proximal Femur Fractures Flashcards
Occurrence of proximal femur fractures?
Most are in those >80 years and 75% are female
Very common due to increase in the ageing population and osteoporosis
Causes of proximal femur fractures?
Falls:
• There may be an underlying cause - CV disease (e.g: TIA), cardiac arrhythmia, postural hypotension
• Mechanical fall
• Usually, no obvious organic cause falls
Osteoporosis:
• Age-related qualitative defect of bone (more common in females)
• May be related to smoking, alcohol, steroids
Why do most people have surgery, despite the assoc. morbidity and mortality?
Non-operative Mx is very painful and the risk of prolonged bed rest are just as high as the risk of surgery
Surgery affords the best chance of returning home
Which patients do not have surgery for proximal femur fractures?
Patients with severe co-morbidites (massive stroke, MI, etc) and those who are expected to die with surgery
Consequences of proximal femur fractures, in terms of independence?
Most patients drop a level of mobility:
• Stick - 2 sticks - walker / frame - needs assistance - wheelchair - hoist
Independent patients have a 1/5 risk of requiring institutional care
What are the risk of surgical complications?
- Failure of fixation (screws may not hold in osteoporotic bone)
- AVN (avascular necrosis)
- Non-union
- Infection (risk is higher with this surgery than for THR)
- Dislocation
Examination findings with a proximal femur fracture?
- Shortened and externally rotated leg
- Trochanteric bruising and tenderness
- Unable to SLR
- Severe groin pain on rotational movements
What is the most powerful flexor of the hip joint?
Iliopsoas
Describe the blood supply to the femoral head
Branches of the femoral artery winds around the neck and branches of these supply the femoral head
Artery of ligamentum teres only supplies 5%
What is the capsule of the hip joint?
AKA capsular ligament - strong and dense
3 types of proximal femur fractures?
- Intracapsular - inv. the femoral neck, between the edge of the femoral head and insertion of the capsule of the hip joint
- Extracapsular - distal to the insertion of the capsule, inv. or between the trochanters
- Subtrochanteric - below, but no more than 5 cm below, the lesser trochanter, i.e: inv. the proximal femoral shaft at/just distal to the trochanters
Ix for proximal femur fractures?
X-ray (GOLD STANDARD - require 2 views at 90 degrees to one another)
MRI for occult fractures
Complications of intracapsular proximal femur fractures?
Can interrupt the blood supply and there is a risk of AVN (higher with displaced fractures); AVN is not a risk with extracapsular fractures
Risk of non-union
Signs of fractured proximal femur on X-ray?
Interrupted Shenton’s line - imaginary line drawn along the inferior border of the superior pubic ramus and along the inferomedial border of the neck of femur; it should be continuous and smooth (DIAGNOSTIC if interrupted)
Centre of the femoral neck does not bisect the centre of the femoral head
Treatment of intracapsular proximal femur fractures?
Replacement is a reliable option:
• Hemiarthroplasty (acetabulum is left alone) is used in those with poorer function/cognitive deficit as there is a lower chance of dislocation
• THR gives a better functional outcome but there is a higher dislocation rate
Consider fixation in:
• Undisplaced fractures
• Intracapsular fractures in a younger patient
What to do if the MRI is +ve for an intracapsular proximal femur fracture but the X-ray is -ve?
There is a risk of displacement with weight-bearing
Surgery may provide better pain relief and easier rehabilitation but the pros and cons should be discussed with the patient and their family
Complications of internal fixation for intracapsular proximal femur fractures?
Fixation may fail, e.g: screws slide out, and this would then require a THR
Treatment of extracapsular proximal femur fractures?
Usually heal with a sliding hip screw (Dynamic Hip Screw/DHS) which compresses the fracture site
An IM nail and sliding hip screw can also be used
What does the success of fixation of an extracapsular fracture depend upon?
Quality of reduction
Centrality of screws in the head
Occurrence of subtrochanteric fractures?
Assoc. with long-term bisphosphonate use
Complications of subtrochanteric fractures?
Blood supply to this fracture site is not great so there is a higher risk of NON-UNION
Treatment of subtrochanteric fractures?
Thomas splint or femoral nerve block can help with analgesia
IM nail is biomechanically superior (may last longer before breakage if there is delayed union)
Describe pubic rami fractures
These are different from the high-energy pelvic fractures that tend to occur in young patients; these tend to occur in fragile patients who fall on their side
There is no major displacement or bleeding
Examination findings with pubic rami fractures?
Tender groin
Less pain on rotation than in a hip fracture
Treatment of pubic rami fractures?
Conservative Mx
Treatment of greater trochanter fracture?
Usually conservative Mx
If an MRI shows that the fracture traverses the femoral neck, then internal fixation can be used
Only proven method that prevents proximal fractures?
EXERCISE helps to maintain muscle strength and bone mineral density
There are no drugs that increase bone density; bisphosphonates may stop loss of bone density but they are assoc. with atypical fractures
