Fibular Fracture

Description

Fractures of the tibia and fibula are common in athletes especially runners or non-athletes who suddenly increase their activity. Several factors appear to contribute to the development of this fracture including changes in athletic training specific metabolic factors that lead to bone loss density and diseases.[1] Sometimes the fibula is fractured while the ankle is severely fractured. The fracture can occur anywhere along the fibula. The fibula carries only 17% of body weight so these fractures are not as severe as weight-bearing fractures.[2]

Clinically Relevant Anatomy

The fibula is a non-weight-bearing bone that originates just below the posterior tibial plateau and extends distally to form the lateral malleolus, which is the distal portion of the fibula to the upper articular surface of the talus. The lateral malleolus provides primary stability from overload eversion of the ankle and foot. Near the fibular head is the point of attachment of the posterior collateral ligament of the knee and the muscle from the biceps femoris. Just below the fibular head, the common peroneal nerve attaches to the fibular neck before distributing over the proximal fibula into deep and superficial branches.[1]Along the superior and medial posterior borders of the fibula, the Peroneal (Fibularis)Longus and brevis muscles originate and provide a soft tissue sheath to protect the fibula from of direct contusion. The connective tissue between the tibia and fibula tibiofibular syndesmosis prevents displacement of the lateral malleolus. The distal portion of the syndesmosis has fibers that have thickened to form the distal tibio-fibular ligament. The stability of this muscle maintains the stability of the toe during external rotation and acute cutting movement required in many sports. Damage to syndesmosis (syndesmotic or horizontal ankle sprain) contributes to tibiotalar joint instability.[1]

The fibular bone.

The peroneal longus muscle (in red)

Mechanism of Injury

The mechanisms of tibia-fibula fracture injuries can be divided into 2 categories:

• low-energy injuries such as falls and sports injuries
• high-energy injuries such as vehicular injuries to pedestrians struck by vehicles and gunshot wounds.

Patients may report a history of direct (car crash or axial loading) or indirect (twisting) trauma and may complain of swelling pain and immobility with tibia fractures. [4] .

Classification

Ankle fractures are classified according to the Danis-Weber classification system [5].

• Type A is a transverse fibular fracture caused by adduction and internal rotation.
• Type B is caused by posterior rotation and is characterized by a short oblique fibular fracture oriented mediolaterally upward from the tibial plafond.
• There are two type C fractures: Type C 1 is an oblique medial-to-lateral fibular fracture caused by abduction. Type C 2 fractures result from a combination of abduction and external rotation resulting in a more extensive syndesmotic injury and a high fibular fracture.

The Danis-Weber classification system uses the position of the position of the fibular fracture in relation to its height at the ankle joint.

• Type A: tumors below the ankle joint
• Type B: fractures at the joint level with the tibiofibular ligaments usually intact.
• Type C: fracture beyond the joint separating the syndesmotic ligaments.

The Danis-Weber classification types.

Epidemiology/Aetiology

Distal fibular fractures represent the majority of ankle fractures. [6] Cord ruptures in younger adults are more commonly caused by trauma but compared to elderly cord ruptures that typically occur as a result of low-energy injuries, the extent of nerve damage is similar. [7] . Isolated cord fractures contain the majority of ankle fractures in older women occurring in approximately 1 to 2 per 1000 white women per year.[8] Fibular fractures can also occur as a result of repetitive loading and in this case are called stress fractures.

Risk factors

Bone mass is the primary risk factor for fibular or tibial shaft fractures in older adults. Factors that reduce bone density had a greater impact than overall health status or other risk factors for falls. [9] Smoking is another important risk factor for fibular fractures.[10]

Fibular fractures are common in athletes who participate in sports that involve cutting especially those involving contact or collision for example American soccer ball and rugby. [11] Participants in moderate winter sports have a higher rate of fibular fractures. These are more than that more common in snowboarding than skiing and the uniqueness of the fractures. Skiers typically fracture the proximal third of the tibia as well as the fibula while snowboarders frequently suffer isolated fractures of the distal portion of the fibula. [12] .

Clinical Presentation

A fractured fibula usually presents with the following signs and symptoms: [13] .

• pain, swelling and tenderness;
• inability to bear weight on the injured leg;
• bleeding and bruising in the leg;
• visible deformity;
• numbness and coldness in the foot
• tenderness to touch.

Diagnostic Procedures

• Physical examination: A thorough examination is performed, including checking for any obvious deformities.
• X-rays are used to look for fractures and possible bone displacement.
• An MRI scan provides a more detailed scan that can produce detailed pictures of internal bones and soft tissues.
• A bone scan CT scan and other tests may be ordered to make a more accurate diagnosis and determine the severity of the fibula fracture. [13]

Differential Diagnosis [14]

• Acute Compartment Syndrome
• Tibia Fracture
• Ankle Fracture
• Ankle Injury, Soft Tissue
• Child Abuse
• Knee Fracture
• Pediatric Limp
• Peripheral Vascular Injuries
• Soft Tissue Knee Injury

Management / Interventions

Distal fibula fractures mainly require open reduction and surgical fixation [15], but in stable minimally displaced fractures conservative treatment may achieve good results. [16] If the fracture is open, additional management is required to reduce the risk of contamination and infection.

Physical therapy management

After a few weeks of using a cast or splint, most people find that their legs are weak and their joints are stiff. Physiotherapy is administered after an individual assessment of the patient. It is important to evaluate the following:

• Pain and oedema
• Range of motion (ROM)
• Muscle strength
• Surgical scar tissue
• Patient ambulation and weight bearing

Physical therapy usually begins with ankle strengthening and mobility exercises. Once the patient is strong enough to bear weight on the injured area, walking and stepping exercises are common. Balance is an important part of regaining the ability to walk independently. Wobble board exercises are a great way to Work in balance. [13]

According to the ORIF postoperative fibular fracture protocol, fibula fracture rehabilitation is divided into 4 phases:[17]

Phase 1 – Maximum Protection (Weeks 0 to 6)

• Cast or boot for 6 weeks
• Elevate the ankle above the heart
• Non-weight bearing x 6 weeks
• Multi-plane hip strengthening
• Core and upper extremity strengthening

Phase 2 – Range of Motion and Early Reinforcement (Weeks 6 to 8)

• Full active and passive painless ROM full face
• Strong emphasis on returning to full dorsiflexion
• Isometric and Early Isotonic Ankle Exercises
• Foot intrinsic muscle strengthening
• Gradually progress to full weight bearing
• Restoration of normal gait mechanics
• Bilateral Progression to Unilateral Squat Step and Matrix Progression
• Proprioception training
• Non-impact cardiovascular work

Phase 3 – Progressive Strengthening (Weeks 8-12)

• Restores full range of motion in all planes
• Advancing Intrinsic Strengthening of the Ankle and Foot
• Pool running progressing to dry land
• Linear progression to lateral and rotational functional movements
• Bilateral Progression to Unilateral Plyometric Activities

Phase 4 – Advanced Reinforcement (Weeks 12-16)

• Advancing Impact and Feature Progress
• Sports-specific training on the field or court with functional braces
• Exercise testing at 3-4 months depending on progress [18]

For long-term care to reduce fracture risk, it is important to:

• Wear appropriate footwear;
• Eat calcium-rich foods, such as yogurt and cheese, to help build bone strength;
• Do weight-bearing exercises to help strengthen your bones. [13]