Abstract
Tibiofemoral joint dislocations are uncommon. Four cases of paediatric knee dislocation are described, none in British journals.
We report two paediatric patients who presented with a 3-ligament knee injury following in-field or spontaneous reduction. One case was initially diagnosed as patella dislocation.
One patient, age 12 years, had associated nerve and vessel injury so underwent fixation, vascular grafting and fasciotomy emergently. The second, age 15 years, underwent acute reconstruction following MRI evidence of both cruciates and medial-collateral ligament ruptures, with tears to both menisci.
History is essential to diagnosis as the knee is often relocated at the scene. Tibiofemoral dislocation can be confused with patellofemoral dislocation. There are important differences on examination, which should be performed carefully, and must include neurovascular status. Knee AP and lateral radiographs can exhibit subtle signs, posterior subluxation of the tibia is pathognomonic of PCL rupture and should raise suspicion of dislocation.
These cases show that traumatic dislocation is an important differential diagnosis in a child that presents with a painful knee. Although an uncommon injury, particularly in the skeletally immature, it is essential to recognise the possibility of knee dislocation in children so that prompt diagnosis and treatment of this limb threatening injury can occur.
