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The kneecap connects the muscles in the front of the thigh to the shin bone. It allows us to bend and straighten our knees. The kneecap sits in a groove on the thigh bone.

What is an unstable kneecap?

An unstable kneecap is when the kneecap slips out of its groove or dislocates. When this happens, it can damage cartilage, and the soft tissue including stretching or tearing the patellofemoral ligament.

What causes an unstable kneecap?

When the groove in the thighbone is too shallow or uneven the kneecap can slide off, and dislocate. This is an anatomical problem that can be treated with surgery.

A sharp blow to the knee from direct contact, or a fall can also cause the kneecap to slip out of place or dislocate.

What are the symptoms of an unstable kneecap?

The knee buckles, the leg cannot support your weight, there is pain at the front of the knee with movement, swelling and stiffness, creaking sounds, and pain while sitting. Apprehension to bending or using the knee can occur.

How is an unstable knee diagnosed?

Dr. Van Thiel will conduct an examination to determine if the bones are in alignment, test the strength of your thigh muscles, and ask you to walk around or to bend and straighten the knee. He may order x-rays to see how the kneecap fits into its groove. An MRI may be ordered to evaluate the knee ligaments for damage, and to detect cartilage injury which is common with a dislocation.

What is the treatment for kneecap instability?

When the kneecap dislocates it comes out of its groove, and may go back into its groove by itself. If not, Dr. Van Thiel will apply gentle force to push the kneecap back in to its proper location. This is called a reduction.

Once you experience a dislocation, it increases the risk of more dislocations which can damage the kneecap and the thighbone, and stretch the knee ligaments causing additional pain and instability. If left untreated, the result will be arthritis of the kneecap.

If this is the first dislocation, standard care is nonsurgical treatment. This will begin within the first few days of the dislocation, and include immobilization with a brace or splint, and physical therapy. This approach will allow you to return to your daily activities within a few weeks.

When is surgery needed?

The goal of surgery is to stabilize the kneecap so you can get back to the sports you love and your daily activities. Most important is protection of the cartilage under the kneecap to avoid damage and the risk of developing arthritis in the knee. We know that cartilage damage occurs every time the kneecap dislocates.

  • When a patient experiences more than one dislocation, surgery will be recommended to prevent additional instability and protect the cartilage from further damage,
  • Surgery will be recommended to treat a badly damaged ligament.
  • Surgery will be recommended when a piece of bone or cartilage comes loose and causes the knee to lock up. Arthroscopic surgery will remove the loose pieces, and stabilize the kneecap.

Knee stabilization surgery offers reliably good results, and should be pursued before cartilage damage occurs. However, if there is cartilage damage due to instability, Dr. Van Thiel may recommend procedures for cartilage restoration.

How long does it take to recover from knee stabilization surgery?

With extensive physical therapy, and activity modification, it can take 3-6 months to recover from surgery.

Dr. Van Thiel treats patients from all over Wisconsin and Illinois including Rockford, Elgin, Huntley, Dekalb, Crystal Lake, Barrington, McHenry, and Beloit. Schedule an appointment with him today.

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