Question
A 60 year old woman trips and lands on her knee. She cannot perform a straight leg raise.
- Describe the radiograph.
- What are the indications for surgery?
- Describe your fixation options and their complications.
Answer
Radiograph
- Displaced transverse fracture of the patella
- Separation of the fragments with a haemarthrosis
- Loss of active extension means the retinacula are torn
Indications for surgery
- Extensor mechanism failure (no straight leg raise)
- Articular step over 2 mm
- Fragment separation over 3 mm
- Open fracture
Non-operative
- Intact extensor mechanism and minimal displacement
- Brace locked in extension, early weight bearing, progressive flexion
Fixation
- Tension band wiring with K-wires or cannulated screws
- Cannulated screws with a tension band are stronger than K-wires
- Mesh or fixed angle plates for comminution
- Repair the retinacula
- Partial patellectomy with tendon advancement for unreconstructable inferior pole fragments
- Total patellectomy as a last resort
Complications
- Symptomatic hardware, removal in up to half
- Loss of fixation
- Stiffness and quadriceps weakness
- Patellofemoral arthritis
- Infection
Related pages
Author Contributions
Orthofracs team
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.