Classification, Clinical Diagnosis and Treatment of Intertrochanteric Fractures of the Femur

Ward's Triangle

A triangular vulnerable area is formed in the central area where the femoral neck trabeculae cross. In elderly people with osteoporosis, this area is only filled with fat.

Femoral Calcar

A dense bone plate located posterior - medial to the junction of the femoral neck and shaft deep to the lesser trochanter. It is an extension of the posterior - medial cortex of the femoral shaft into the cancellous bone and is the point of application of eccentric load on the proximal femur.

Grading of Hip Bone Trabeculae

 Grading of the mechanical strength of the proximal femur:
(1) Grade 6; (2) Grade 5; (3) Grade 4; (4) Grade 3; (5) Grade 2; (6) Grade 1

High - energy Injuries in Young Patients

Intertrochanteric fractures in young patients are usually caused by high - energy injuries such as falls from a height and car accidents. These situations may lead to severe fractures, and patients need to be closely monitored for associated injuries, including those to the head, spine, and thoracic and abdominal organs.

Factors of Falls in Elderly Patients

90% of intertrochanteric fractures in the elderly are caused by falls. Factors contributing to the tendency of the elderly to fall include poor eyesight, reduced muscle strength, unstable blood pressure, decreased reaction ability, vascular diseases, and bone and joint diseases.
   Whether a fall results in a fracture is determined by the following five factors: the severity of osteoporosis, the direction of the fall, especially when the hip or an area close to the hip hits the ground, the insufficiency of protective reflexes to reduce the energy of the fall, the inability of the hip soft tissues to absorb sufficient energy, and the insufficient strength of the hip bones.

Types of Violence and Mechanisms of Action

1. Direct Violence: High - energy injuries act directly on the hip, such as traffic accidents or falls where the hip is directly impacted, leading to fractures.

2. Indirect Violence: Body torsion subjects the hip to varus and forward angulation stress. With the lesser trochanter as the fulcrum, it is strongly compressed, and there may also be the pulling effect of the iliopsoas muscle, forming a butterfly - shaped bone fragment. The greater trochanter may also form a separated bone fragment due to the strong pulling of the gluteus medius muscle.

Evans Classification

 The most commonly used in clinical practice. Evans divided intertrochanteric fractures into two types:

1. Type I:Trans - trochanteric fractures    According to the stability before and after reduction, it is further divided into 4 subtypes:

• Ⅰa: Two - part fracture without displacement.

• Ⅰb: Two - part fracture with displacement, the medial cortex is relatively intact, and the fracture is stable after reduction.

• Ⅰc: The lesser trochanter is free, with fracture displacement and varus deformity; or the greater trochanter is a separate bone fragment.

• Ⅰd: In addition to the intertrochanteric fracture, both the greater and lesser trochanters become separate bone fragments, with varus deformity.

• Among them, types Ⅰa and Ⅰb are stable types, and the rest are unstable types.

2. Type II:Reverse - oblique intertrochanteric fractures
   Type II is a reverse - trochanteric fracture, with the fracture line extending obliquely from below the greater trochanter to the upper part of the lesser trochanter.

AO Classification

Type A1: Simple two - part fractures through the trochanter, with good support of the medial bone cortex and intact lateral bone cortex.

1. Along the intertrochanteric line.

2. Through the greater trochanter.

3. Through the lesser trochanter.

Type A2: Comminuted fractures through the trochanter, with fractures of the medial cortex in two planes, but the lateral bone cortex remains intact.

1. With one medial fracture fragment.

2. With several medial fracture fragments.

3. Extending more than 1 cm below the lesser trochanter.

Type A3:  Reverse - intertrochanteric fractures, with fractures of the lateral cortex as well.

1. Oblique.

2. Transverse.

3. Comminuted.

Generally, types A1.1 to A2.1 are considered stable, and types A2.2 to A3.3 are considered unstable.

PFNA for the Treatment of Intertrochanteric Fractures of the Femur

PFNA is used for unstable osteoporotic intertrochanteric fractures such as Evans Ic, Id, and Type II. It has better performance, good anti - rotational ability, short operation time, less blood loss, fewer complications, and a lower probability of proximal locking nail cut - out, showing obvious treatment advantages.

INTERTAN for the Treatment of Intertrochanteric Fractures of the Femur

With the development of modern medical technology, INTERTAN is a new type of intramedullary nail specifically designed for the treatment of intertrochanteric fractures of the femur. The cross - section of its main nail is trapezoidal. When used in combination with the proximal interlocking combined nail, it can prevent the "Z" effect. The addition of a secondary nail protruding from the femoral head increases the anti - rotational effect of the lag screw. This intramedullary nail has a wide range of applications and is suitable for patients with severe osteoporosis.