Fast track your treatment
To book an appointment or speak with one of our friendly team, please get in touch using the options below
A procedure to stabilise the knee joint
The kneecap is a small bone that sits at the centre of the knee. As well as helping the leg to extend, the kneecap also protects the joint from impact. The kneecap is secured in place with a tendon at the top and a ligament at the bottom.
When the knee is bent or extended, the kneecap slides along a groove in the bottom of the thigh bone .
Sometimes the kneecap can slip out of this groove. When this happened the kneecap can become dislocated. A kneecap dislocation can damage the cartilage in the shinbone and the thigh bone. Kneecap stabilization surgery (patella stabilisation surgery) is a procedure to stabilise the knee joint.
Because of the demands placed upon the knee during physical activities, it is particularly prone to sporting injuries.
Instead of a deep socket to maintain the stability of the joint, the kneecap joint (patellofemoral joint) relies on the thigh muscles (quadricep muscles) and surrounding soft tissue for this role.
Due to the huge forces that this joint experiences with every day and sports-related movements, this stability can sometimes be compromised with a traumatic kneecap dislocation.
In other circumstances, the kneecap may be unstable due to inherent, developmental factors. For example, the groove for the kneecap to sit in may not be deep enough or very flexible soft tissue structures in individuals with hypermobility syndrome. When this happens it is sometimes called a patellar subluxation.
Patellar subluxation results in an instability in the knee, which can pull the kneecap out of the groove and towards the outer side of the knee. This is less severe than a knee dislocation, which occurs when the kneecap completely pops out of the groove and sits on the outside of the knee joint.
Kneecap stabilisation surgery is a treatment option that aims to return the kneecap to its correct position in front of the knee.
Look out for the following symptoms if you believe that you may have an unstable patella:
If the kneecap repeatedly dislocated, it can cause the supporting ligaments to become stretched. This, in turn, increases the risk of repeated dislocations.
You would normally be admitted the evening before the operation if it is in the morning, or early on the day if your operation is scheduled for the afternoon or the evening. This allows you time to settle in and prepare for the procedure.
During the procedure, your surgeon will make a small incision down the front of your knee. The consultant will then assess the problem and then determine which procedure is best to stabilise the kneecap, such as an arthroscopic patella realignment.
Depending on the underlying cause of the kneecap instability, patellar stabilisation surgery can be performed in a number of ways.
One part of the surgery will often involve tightening up the stabilising soft tissue structures on the inside of the kneecap. This can help to prevent the kneecap from dislocating sideways in the opposite direction (laterally).
Another part of the surgery can be simultaneously releasing some of the structures towards the outside (lateral) aspect of the kneecap. This will be considered if these structures are considered too tight and the release can prevent excessive pulling of the kneecap laterally, which can lead to dislocation.
In many cases surgeons will also move the insertion point of the patellar tendon further towards the inside of the knee. This part of the procedure is termed a tibial tuberosity transfer. This positions the patellar further towards the inside of the patellofemoral joint groove leading to less chance of dislocation.
Patients may also be non-weight bearing or partial weight bearing for a period of time. This is to allow the bone to heal if a tibial tuberosity transfer has been performed and to allow the soft tissue tightening to heal.
Once these restrictions have been lifted, physiotherapists will create a comprehensive rehabilitation package to help you return to activities of daily living and sports as appropriate. These exercises will help you to strengthen the muscles in the leg, which will help the healing of the knee following surgery.
If the kneecap has been repeatedly dislocated, a kneecap stabilisation can help reduce the chance that the kneecap will dislocate in the future. This will reduce any further damage to the knee, which may delay the need for further, more significant, surgery, such as a kneecap replacement or knee replacement surgery.
Most people who have knee stabilisation surgery make a full recovery and don’t experience complications. However, there are some potential side effects. Your consultant surgeon will discuss the potential risks with you prior to surgery.
Complications can include: