Intertrochanteric Fracture
- Extracapsular fracture of the proximal femur – between the greater and lesser trochanter
Epidemiology
- Female preponderance
- Proximal humerus fracture increases risk of trochanteric fracture
- Incidence of non-union and avascular necrosis is low due to rich blood supply
Etiology/pathophysiology
- High energy trauma in young patients
- Low energy trauma (falls) in older patients
Anatomy
- Blood supply – originates from deep femoral artery, gives off two branches
- Medial and lateral femoral circumflex arteries – they loop around the base of the femoral neck to form the extracapsular ring
- This gives off several small ascending cervical branches which penetrate the capsule – run proximally within the joint, close to the femoral neck
- When they reach the articular surface they form the subsynovial intracapsular ring
- Calcar femorale – vertical ridge of dense bone
- Originates from the postero-medial aspect of the femoral shaft, near the lesser trochanter
- Projects laterally toward the greater trochanter
- Provides mechanical support
- Helps determine stable vs unstable fracture patterns
Classification
- Stable – intact posteromedial cortex
- Once reduced it will resist medial compressive forces
- Unstable – comminution of posteromedial cortex
- Once reduced, fracture will collapse into varus
Clinical features
- Pain
- Shortened, externally rotated leg
Diagnosis
- X-ray
- CT/MRI
Treatment
- Dynamic hip compression screw – for stable fracture
- Intramedullary hip screw
- Arthroplasty – for severely comminuted fractures; patients with pre-existing arthritis
Subtrochanteric Fracture
- Subtrochanteric area is up to 5cm below the lesser trochanter
Epidemiology/etiology
- High energy trauma in young patients
- Low energy trauma in old patients
- Long-term use of bisphosphonates
- More unstable than intertrochanteric fractures
- Higher incidence of non-union than intertrochanteric fractures
Classification – Russel-Taylor Classification
- Type I – no extension into piriformis fossa
- Type II – extension into greater trochanter with involvement of piriformis fossa
Clinical features
- Hip and thigh pain
- Inability to bear weight
- Pain with motion
- Deformity – varus and shortening
Diagnosis
- X-ray
- CT
Treatment
- Observation and pain management – for non-ambulatory patients with co-morbidities who may not be able to tolerate surgery
- Intramedullary nailing – preferred choice of treatment
- Fixed angle plate – for patients with associated femoral neck fracture