Ankle fractures

Isolated injuries of the leg bones

Injuries to one of the bones of the lower leg have their own biomechanical features. With an isolated fibular fracture, complications are rare, and thanks to natural support from the undamaged tibia, healing occurs without significant issues. Patients are allowed partial weight-bearing with a cane, and full working capacity returns in about five to six weeks.

Isolated tibia injuries are more severe. Since the intact fibula acts as a kind of splint, axial (longitudinal) displacement of fragments is atypical for such injuries. However, transverse or angular displacement often occurs. This creates a high risk of muscle interposition — soft tissues getting trapped between the edges of the broken bone.

Diagnosis is based on visual deformity, pain upon axial loading (heel tapping), and local tenderness upon palpation of the bone crest. To confirm the diagnosis, X-rays capturing both the knee and ankle joints are mandatory.

Shaft fractures of both bones

When both bones of the lower leg break, the mechanism of injury is of decisive importance:

• Direct impact: (e.g., a typical "bumper" injury in a car accident). Both bones break at the same level. The tibia is often shattered into multiple fragments.
• Indirect (torsional) mechanism: Occurs during sudden rotation of the lower leg when the foot is rigidly fixed. In this case, the bones fracture at different levels: tibia spirally in the lower third, and fibula in the upper third.

The clinical picture of such injuries is pronounced. The distal part of the leg turns outward under the weight of the foot. The skin over the central fragment becomes taut and pale, and with severe edema, blisters (phlyctenae) may appear. A characteristic sign of soft tissue interposition is the dimpling sign — a funnel-shaped depression of the skin when pressing on the protruding fragment.

Conservative treatment and immobilization

Treatment tactics directly depend on how stably the fragments are held in place. If the fracture is undisplaced or easily reducible (e.g., with a transverse fracture line), casts are applied.

First, a split cast is applied, and after the primary edema subsides (in a few days) — a solid circular cast. The duration of wearing a cast varies from 10 to 16 weeks depending on localization and severity. Injuries in the lower third heal longer due to meager blood supply.

With significant displacement, skeletal traction (with a 5–7 kg weight) can be used, acting either as standalone treatment for 3–6 weeks (followed by transition to a cast) or as preparation for surgery. Traction is not used in isolated tibia fractures, as the intact fibula prevents the fragments from being stretched.

Surgical treatment (Osteosynthesis)

Today, surgical fixation is the gold standard for diaphyseal leg fractures, especially if fragments are irremediable (tissue entrapment) or unstable. The surgeon's main task is to perfectly align and fix the tibia, as it bears all the weight-bearing load.

The following types of fixation are used:

1. Intramedullary osteosynthesis: Insertion of a nail into the medullary canal. Performed minimally invasively under X-ray guidance.
2. Plating (Extramedullary): Installation of support plates (often in the lower third of the bone).
3. External fixation: External fixation devices, which are indispensable for open fractures.

The fibula is rarely fixed — mainly if the fracture is in the distal third or accompanied by distal tibiofibular syndesmosis rupture. The main advantage of surgery is the absence of the need to wear a heavy cast and the ability to quickly start joint mobilization.

Class and exam questions

What else to study on this topic

• Compartment syndrome: pathogenesis and emergency care
• Fibular nerve complications in fibula head injuries
• Early functional weight-bearing in short leg casts
• Biomechanics of distal tibiofibular syndesmosis rupture

Other topics in the "Specialized Adult Traumatology" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.