[Fractures of the patella].

With 1% of all skeletal fractures patellar fractures are rare. The majority of cases are caused by a direct trauma to the flexed knee. The diagnosis is made via the injury mechanism as well as the physical and radiological findings. In conventional x‑ray imaging the extent of injury often is underrated, which mostly leads to the necessity of a computed tomography (CT) scan. The aim of the treatment is the reconstruction of the extensor mechanism and the anatomical reconstruction of the articular surface. The type of treatment depends on the fracture type. Tension band wiring still is the most frequently practiced technique. Complications, such as secondary dislocation or migration of the K‑wires resulting in revision surgery have been described in up to 30% of the cases. Studies could already show a higher biomechanical stability of osteosynthesis via cannulated screws. Especially in cases of comminuted fractures, osteosynthesis via a locking plate seems to have several advantages but long-term results are not yet available.