Patella Dislocation

If the patella dislocates it can make the knee suddenly quite painful. If the patella remains out of position it is very difficult to stand up and the knee remains bent. In some patients it relocates spontaneously or if the leg is straightened. Swelling may persist for a few weeks and often confidence in the knee is lost.

The majority of people who suffer a dislocation of the patella have a shallow groove for the patella to track in which allows the patella to slip off the edge of the groove to the outside of the knee. It is frequently precipitated by a twisting movement. Unfortunately, when the patella dislocates it can tear the medial patella femoral ligament. Once torn this ligament heals poorly the patella is prone to further dislocations in future.

When the patella dislocates it sits on the outside of the knee. It often relocates if someone helps you straighten the knee. It may require you to attend accident and emergency. Once back in place the knee pain improves considerably. The knee will swell and may feel insecure.

In general, treatment options you might like to try may include:

• Rest, ice, compression, and elevation (RICE) to help manage pain and swelling.
• Physiotherapy to help strengthen the muscles around the knee and improve flexibility.
• Anti-inflammatory medication can help but don't take them for a prolonged period without advice from your doctor.

Your knee swelling may settle down and if you strengthen the leg it is possible that the knee can recover. Only approximately 50% will suffer a further dislocations. Some patients get a sense that the patella is trying to dislocate but it doesn’t actually do so (called subluxation). When the patella dislocates it can knock a piece of cartilage off which can become a loose body which may in itself cause the knee to jam or lock.

Treatment options for patella dislocation

• Non-operative treatments include rest, ice and support sleeve. This may be then followed by physiotherapy to strengthen the muscles of the leg.
• A patella trainer knee support may help improve the stability of the patella and may allow you to get back to sports.
• If the knee has subluxations or a further dislocation you may wish to consider surgery. The procedure most frequently carried out is medial patella femoral ligament reconstruction (MPFL), a hamstring tendon is used to substitute for the ruptured MPFL. It has a high success rate but is an intricate procedure that should only be carried out by a knee specialist who is familiar with this type of surgery. Other surgeries can involve moving the tendon (tibial tubercle transfer) or deepening the groove (trochlearplasty).

I have a great deal of experience in patella stabilisation surgery but also in the non-operative treatments. I published work on the MPFL before it became a mainstream knee procedure for the management of patella dislocation. Patella dislocation is relatively uncommon so many have never seen a specialist and may feel confused about their options for treatments. I find that part of the problem is that the dislocations are uncommon but that the significant loss of confidence affects all aspects of life, not just sports. For that reason many feel they can’t play sports or even dance at a party. I will help you understand whether surgery is right for you and if you go ahead, I will work together closely with your physiotherapist to ensure we get you back to all the things you are missing out on.