Fractures that involve the patella (knee cap) are common injuries that usually result from a direct blow to the patella. Treatment depends on the amount of displacement of the fracture and whether the patient can straighten their leg. In non-displaced fractures, the bone has a small fracture, but the integrity of the soft tissue structures around the knee is not compromised.
In these cases, surgery is not indicated and these injuries are treated with a long leg cast and gradual progression of function. Surgery is required when the fracture is displaced or the soft tissue envelope has been disrupted. Surgery generally takes about 1 hour and involves realigning the bone and repairing the fracture with metal implants. Often, the surgery can be performed as an outpatient. Recovery is slow, usually taking 4-6 months to recover muscle strength and range of motion. The implants can cause irritation over the kneecap and may be removed after 12 months.