Curriculum · Musculoskeletal / Orthopedic / Rheumatology
Patellar fracture
What it is
A fracture of the patella.
Causes and risk
High energy trauma. The mechanism is either a direct blow to the patella, in a fall or an MVC against the dashboard, or indirect trauma by sudden flexion of the knee against a contracted quadriceps. The important blood supply is at the inferior pole.
How it is treated
Non operative treatment is indicated for a non-displaced fracture, that is a step-off under 2-3 mm and a fracture gap under 1-4 mm: straight leg immobilization for 1-4 wk in a hinged knee brace, weight bearing as tolerated, progressing in flexion after 2-3 wk, with physiotherapy for quadriceps strengthening once the pain has subsided. Operative treatment is indicated for a displaced fracture, over 2 mm, a comminuted fracture, or a disrupted extensor mechanism: ORIF, which if comminuted may require partial or complete patellectomy, with the goal of restoring the extensor mechanism with maximal articular congruency.