Fractures and dislocations of the femur
For anatomy of proximal femur see handwritten notes. Make note of the vasculature and the angle.
Dislocations
Dislocations of the femur can be Anterior or posterior. Such dislocations are the result of high energy trauma, especially dashboard injuries. It is considered an orthopaedic emergency due to high risk of femoral head avascular necrosis. Such dislocations are commonly associated with fractures of the femoral head/neck and acetabulum. Posterior dislocations are significantly more common (85%).
In posterior dislocations the patient presents with an adducted and flexed leg with internal rotation, while the anterior hip presents with abducted and flexed with external rotation. Patients will have pain, especially with motion, it is important to confirm the patency of the sciatic nerve.
Classification of dislocations:
- Posterior: Thompson classification
- Type I - no or minor posterior wall fracture
- Type II - large posterior wall fracture
- Type III - comminuted acetabular fracture
- Type IV - acetabular floor fracture
- Type V - femoral head fracture
- Anterior: Epstein classification
- Type I (A,B,C)
- Tye II (A,B, C)
- A - no associated fracture
- B - femoral head fracture
- C - acetabular fracture
Treatment is early reduction which is essential (should be in less than 6 hours).
- Posterior dislocations
- Type I - closed reduction and abduction pillow
- Type II-V - closed reduction or ORIF if irreducible. Start with ORIF if fracture is unstable
- Anterior dislocation
- Closed reduction, ORIF if required
The main complication is post traumatic osteonecrosis, other complications include sciatic nerve injury (in posterior dislocations), femoral artery/nerve injury (in anterior dislocations) and heterotopic ossification.
Proximal femoral fractures
There are a two main types of proximal femoral fractures, these are:
- Femoral neck fractures
- Intertrochanteric fracture
- Femoral head fractures
Femoral neck fractures (articular)
There are two main population groups that are affected by femoral neck fractures, it most commonly affects those over the age of 65, especially oesteoporetic women, who suffer from low energy falls. The second group is young adults who have high-energy traumas, often in RTAs.
Patients will present following a fall, with pain and an inability to bear weight or walk. The leg will be shortened, abducted and externally rotated (rolling log extremity - due to the fact that the hip joint no longer counteracts the natural tension of iliopsoas m.).
The classification is the Garden classification:
- Type I - incomplete fracture; valgus impaction
- Type II - complete fracture; nondisplaced
- Type III - complete fracture, partial displacement (varus)