Femoral Shaft Fracture

A femoral shaft fracture involves the femoral diaphysis between the subtrochanteric region proximally and supracondylar region distally.

In young adults it is usually a high energy injury and should be considered a marker for potentially serious associated trauma.

A closed femoral shaft fracture can conceal approximately 1 to 1.5 litres of blood, and open injuries may lose considerably more.

AO/OTA classification

Femoral shaft fractures are coded 32.

32A: Simple

• A1 spiral
• A2 oblique, fracture line greater than approximately 30°
• A3 transverse, less than approximately 30°

32B: Wedge

• B1 spiral wedge
• B2 bending wedge
• B3 fragmented wedge

32C: Multifragmentary or complex

• C1 complex spiral
• C2 segmental
• C3 irregular multifragmentary.

Winquist Hansen classification

This older system describes comminution and remaining cortical contact.

Type 0

• No comminution

Type I

• Minimal comminution

Type II

• Comminution with more than 50% cortical contact remaining between main fragments

Type III

• Comminution with less than 50% cortical contact

Type IV

• Complete circumferential comminution or segmental pattern with no meaningful cortical contact.

Modern locked intramedullary nails have reduced its role in choosing fixation, but it remains useful for understanding mechanical stability.

The thigh is painful, swollen, shortened and often deformed.

Assess haemodynamic status early because significant occult blood loss may occur.

Inspect for an open wound.

Document distal vascular and neurological status.

Assess for compartment syndrome, although thigh compartment syndrome is less common than in the leg.

High energy femoral shaft fracture requires deliberate examination for:

• Ipsilateral femoral neck fracture
• Acetabular fracture
• Knee ligament injury
• Patellar fracture
• Distal femoral fracture
• Chest, abdominal and pelvic trauma

An ipsilateral femoral neck fracture accompanies approximately 1% to 9% of shaft fractures and may initially be missed in a substantial proportion of cases.

Obtain:

• AP and lateral entire femur
• Adequate AP pelvis and hip views
• Knee imaging

High energy trauma CT should be reviewed specifically for occult femoral neck fracture.

A thin slice CT through the hip can improve detection, but nondisplaced neck fractures can still require dedicated imaging when suspicion remains.

Resuscitation

Treat significant haemorrhage according to trauma resuscitation principles.

Provide analgesia and restore gross limb alignment.

A traction splint can temporarily reduce pain, shortening and bleeding during early trauma management in an isolated shaft fracture.

Do not use routine traction blindly when there is an associated:

• Pelvic fracture
• Femoral neck fracture
• Knee injury
• Significant lower leg injury

that makes traction inappropriate.

Definitive treatment

Locked intramedullary nailing is the standard treatment for most adult femoral shaft fractures.

Advantages include:

• Load sharing fixation
• Preservation of fracture biology
• High union rates
• Early mobilisation
• Control of length and rotation

Antegrade nails are suitable for most isolated shaft fractures.

Retrograde nailing is particularly useful in selected situations such as:

• Bilateral femur fractures
• Severe obesity
• Polytrauma requiring rapid supine fixation
• Some distal shaft fractures
• Certain associated pelvic or acetabular injuries

Reduction

Restore:

• Femoral length
• Coronal alignment
• Sagittal alignment
• Rotation

Rotational malalignment is an important but underrecognised complication because standard AP radiographs can appear acceptable despite significant torsion.

Compare cortical profiles and lesser trochanter appearance intraoperatively. If clinically significant malrotation is suspected postoperatively, CT rotational profile of both femora is the most reliable assessment.

Damage control orthopaedics

In a physiologically unstable polytrauma patient, temporary external fixation can rapidly control fracture motion while avoiding prolonged definitive surgery.

Convert to definitive internal fixation after physiological recovery.

Open fracture

Follow full open fracture principles with immediate antibiotics and operative debridement.

Intramedullary fixation can still be appropriate after adequate excision and source control.

Associated femoral neck fracture

Identify the neck injury before or during shaft fixation.

The femoral neck component requires anatomical reduction and secure fixation because displacement, nonunion and osteonecrosis carry greater functional consequences than modest shaft malalignment.

Complications

Fat embolism syndrome

Usually develops 24 to 72 hours after major long bone injury and can cause:

• Hypoxaemia
• Neurological change
• Petechial rash

Treatment is supportive critical care management.

Nonunion

Risk rises with:

• Open injury
• Large fracture gap
• Infection
• Severe soft tissue injury
• Smoking
• Poor mechanical stability

Malrotation

Internal or external rotation above approximately 15° can become clinically significant.

Knee stiffness

Particularly after prolonged immobilisation or associated knee trauma.

Begin knee and hip mobilisation early after stable fixation.