Paediatric Tibial Shaft Fracture
Tibial shaft fractures are the third most common long bone fracture in children and adolescents.
Thirty percent of tibial shaft fractures are associated with a fibula fracture.
Toddler fractures occur in young ambulatory children (from 9 months to 3 years). A toddler’s fracture is a spiral or oblique undisplaced fracture of the distal shaft of the tibia with an intact fibula. The periosteum remains intact and the bone is stable. These fractures occur as a result of a twisting injury.
Tibial shaft (diaphyseal) fractures can be classified by:
Location – proximal, middle, or distal third
Fracture pattern – transverse, spiral/oblique, comminuted or open
Involvement of the fibula
Fractures of the shaft of the tibia can result from a direct blow or a rotational force.
Direct trauma frequently produces a transverse fracture or segmental fracture pattern, whereas rotational forces typically result in an oblique or spiral fracture.
The child will present with pain, swelling and/or deformity in the lower leg. The child will not want to weight bear on the injured leg.
Any patient with a significant mechanism of injury should be assessed via Advanced Trauma Life Support (ATLS) principles.
Anteroposterior (AP) and lateral x-rays of the tibia and fibula to include knee and ankle joints should be ordered.
The reduction is required with any displaced fracture. The majority will require closed reduction.
AP and lateral radiographs of the tibia, including the knee and ankle joints, should be obtained immediately after reduction to verify alignment.
Acceptable reduction parameters –
< 8years: AP or lateral angulation 10 degrees, shortening 10 mm, rotation 10 degrees, apposition 0%
>8years: AP or lateral angulation 5 degrees, shortening 5 mm, rotation 5 degrees, apposition 50%
Toddler fracture– Treatment is supportive. A back slab is applied for 4 weeks.
Undisplaced tibial shaft fracture – No reduction is needed, treated with an above-knee plaster cast and analgesics.
Displaced tibial shaft fracture – Closed reduction and above-knee plaster cast application.
Operative intervention is indicated:
Neurovascular injury with fracture
Extreme swelling/compartment syndrome
Unable to achieve or maintain reduction
Ipsilateral leg injuries
Most fractures will heal well without complication in 8-12 weeks. Close follow-up is important to monitor fracture alignment.
Parents and the child should be given education on cast care.
There is a risk of compartment syndrome with the cast. Provide parents with “Caring for your child in a leg cast” and warning signs of a tight cast: increased pain despite analgesia, change in toes – colour, perfusion, increased swelling. Any concern should prompt an immediate return to the emergency department for evaluation.
Compartment syndrome – soft tissue swelling and circumferential casting can lead to acute compartment syndrome. Signs and symptoms include increasing pain, pain on the passive stretch of the toes, swelling, and late signs of circulation compromise. Injuries with concerning swelling should be splinted and have delayed casting to let the swelling reduce. Close observation and clinical monitoring need to be done for patients with high energy injuries.
Vascular injury – uncommon, however, the sequelae can be serious. Complete vascular assessment needs to be done on all patients with tibia fractures. Proximal tibial shaft fractures are at higher risk of causing a vascular injury.
Angular deformity – tibial varus angular deformity can occur in isolated tibial fractures. Therefore, close follow-up in the first 3 weeks is recommended. Casts can be wedged or repeat reduction may be needed. Patients under the age of 8 should remodel residual angular deformity up to 10 degrees. There is some remodelling for children aged 8-12 years. Children over age 12 have little chance of remodelling residual deformity. Most remodelling occurs in the first 2 years after deformity. Single plane deformity has a higher chance to remodel compared with biplanar deformity.
Malrotation – malrotation of the tibia does not correct with remodelling after injury. Thus limited malrotation can be tolerated. A derotational osteotomy of the tibia may be needed in cases that heal with significant malrotation.
Growth disturbance – growth disturbance can occur due to injury to the proximal tibial physis. This can lead to a recurvatum deformity. This needs to be monitored in patients with proximal tibial shaft fractures who could have injuries that extend into the growth plate.
Leg length discrepancy – accelerated growth after a tibia fracture does not occur as reliably as in femoral shaft fractures. Overgrowth usually does not exceed 5 mm. Leg length discrepancy can result from unrecognized injury to the proximal tibial physis.
Delayed union and non-union – most tibial shaft fractures should heal in 8-12 weeks post-injury with appropriate treatment. Risks for the delay to the union are open fractures and infection. Fractures that result in non-union will need further treatment to promote the union.