Paediatric Fracture Neck of Femur
The paediatric neck of femur fractures is rare and accounts for less than 1% of all paediatric fractures.
These fractures can be classified by the Delbet classification:
Delbet Type I – 5%, fracture goes through the physis (transphyseal)
Delbet Type II – 50%, most common and fracture goes through the middle of the femoral neck (transcervical)
Delbet Type III – 25-30%, fracture goes through the base of the femoral neck (cervicotrochanteric)
Delbet Type IV – 15%, fracture goes between the greater and lesser trochanters (intertrochanteric)
Fracture neck of femur generally occurs from high energy injury mechanisms (such as a fall from a height or motor vehicle collision). Pathologic fractures can occur from lower energy injuries.
The patient will have a painful leg or hip and will not want to weight bear. The leg may be shortened and externally rotated. Patients involved in high energy trauma. Assessment should be made to identify the presence of any other injuries.
All fractures should be assessed using the Advanced Trauma Life Support (ATLS) principles to ensure associated and potentially significant injuries are identified.
Anteroposterior (AP) pelvis and AP/lateral views of the affected femur should be obtained.
Analgesia should be given.
The reduction is required for all displaced fractures. This is performed in the operating theatre.
All fractures need stabilization. The method is dependent upon the patient’s age and fracture pattern.
Parents are explained about the need for operative intervention and the potential complications associated with the fracture neck of femur.
Emphasized to follow up regularly and promptly follow the instruction of the treating doctor.
Avascular necrosis (AVN, also called osteonecrosis) of the femoral head – this is the most common complication following a NOF fracture. The risk of disruption of the blood supply to the femoral head is dependent on fracture type and age. The risk for a displaced Delbet type I fracture is up to 100%, for type II fracture is up to 61%, for type III fracture is up to 27% and for type IV fracture is 14%.
Coxa vara (neck-shaft angle <120 degrees) – this is the second most common complication and has been reported to occur in up to 30% of cases. This can occur from progressive deformity in initially undisplaced fractures or from loss of reduction in displaced fractures. More severe coxa vara can cause abductor dysfunction and result in a Trendelenburg gait pattern.
Growth arrest – the physis of the femoral head contributes to approximately 15% of overall limb length (3-4 mm of growth per year). Reports of early physeal closure following NOF fractures vary in the incidence of 5-65%. It is associated with AVN and transphyseal fixation. Premature physeal closure can result in coxa vara and limb length discrepancy.
Chondrolysis – this is uncommon but can be associated with osteonecrosis of the femoral head due to disruption of the blood supply to the cartilage of the femoral head.
Infection – this is uncommon after surgical fixation of femoral neck fractures. It is reported to occur in less than 1% of cases.