Trochanteric fracture

Trochanteric (femur) fractures are a type of hip fracture. Pertrochanteric and intertrochanteric fractures are at the level of the greater and lesser trochanter, while subtrochanteric fractures are more distal. Pertrochanteric fractures involve both trochanters, whereas the fracture line of an intertrochanteric fracture runs between the trochanters, but the difference is small and so these terms are often used interchangeably. These fractures are roughly as frequent as femoral neck fractures.

Like the other hip fracture, trochanteric fractures are also a condition affecting elderly with high morbidity and mortality. The cause is low-energy trauma, often fall from standing height. Pertrochanteric (involve both trochanters) are the most common type of trochanteric femur fracture, also caused by low energy trauma like other hip fractures. They’re classified according to Evans as stable or unstable. Features are as for other hip fractures, but usually with haematoma. Treatment is ORIF with gamma nail.

Trochanteric femur fractures include:

Type of fracture	Approximate percentage of all hip fractures
Pertrochanteric fracture	30%
Subtrochanteric fracture	10%
Greater trochanteric avulsion fracture	5%
Lesser trochanteric avulsion fracture	1%

Greater and lesser trochanteric avulsion fractures are usually the result of forceful muscle contraction of a fixed limb, which “rips off” the trochanter. This mostly occurs in young and active adults but is rare overall.

Classification

Trochanteric fractures are classified according to the AO or Evans classifications. The Evans classification classifies pertrochanteric fractures as stable (only one fracture line) or unstable (more than one fracture line, no medial support).

Clinical features

As for other hip fractures, the limb is painful, shortened, and externally rotated. As the fracture is extracapsular, there is usually haematoma.

Diagnosis and evaluation

Evaluation with x-ray is usually sufficient.

Treatment

Like femoral neck fractures, trochanteric and pertrochanteric fractures always require surgery. The gold standard for treatment is fixation with gamma nail.

The main complication of fixation with gamma nail for trochanteric fracture is “cut-out”, referring to the collapse of the neck-shaft angle into varus, leading to extrusion of the screw from the femoral head.

Avulsion fractures are the exception, as they are treated conservatively unless significantly displaced.