Broken kneecap

The kneecap is the hard bony structure at the front of the knee. It plays an important role primarily in extending the knee. The kneecap can break. Below we describe how a broken kneecap can occur and what the consequences are.

The medical term for the kneecap is 'patella'. A broken kneecap is also called a patellar fracture.

How does a broken kneecap occur?

Almost always, a hard blow, a so-called high-energy trauma, is the direct cause of a broken kneecap. Such trauma occurs when a body part comes into contact with something with great force or speed, and thus a lot of energy. An example is the kneecap hitting the dashboard of the car during a collision or a fall onto the knee.

In many cases, a broken kneecap is accompanied by injury to the knee ligaments, the surrounding muscles and/or the articular cartilage.

Symptoms of a broken kneecap

Immediately after the accident there is severe pain at the front of the knee and it is impossible to extend the knee or bear weight on the leg. As a result of the fracture, a bruise (black-and-blue mark) or swelling may also be visible at the level of the kneecap.

How is the diagnosis of a broken kneecap made?

The (family) doctor asks what happened and examines the knee. If a fracture of the kneecap is suspected, the doctor will have an X-ray taken. Such an image clearly shows whether the kneecap is indeed broken and where.

If necessary, the knee is further examined in the hospital with an MRI or CT scan. These can show whether there is damage to the knee ligaments or the muscles around the knee. All the information together determines the best treatment.

Treatment of a broken kneecap

There are two options for treating a broken kneecap: with or without surgery. This is largely determined by the severity and direction of the fracture.

If it concerns a fracture line in the longitudinal direction and the bone fragments have not shifted, it may be decided to let the broken kneecap heal without surgery. In that case, the knee will be immobilized with a cast splint for six weeks. After this period, the knee may regain strength through physical therapy.

For more severe fractures, surgery is always chosen. The broken parts are then fixed together with screws and metal tension-band wiring. After surgery, a period of six to eight weeks is advised before the knee may be (lightly) loaded again. This time is needed for the bone fragments to grow firmly back together.

After the advised rest period, it is wise to gradually resume activities under the guidance of a physical therapist. The knee can feel quite stiff and the thigh muscles will also have lost much strength and size. The physical therapist will focus treatment on mobilization techniques, exercise therapy, taping and treatments to reduce pain.

Here you can find a physical therapist who can help you recover well from a broken kneecap.