The patella, also known as the kneecap is a circular-triangular bone which covers and protects the anterior articular surface of the knee joint. Patella surgery may be indicated in a number of conditions associated with the patella.

Reasons for Patella Surgery

There may be need for surgical intervention on the patella for a number of reasons such as:

1. Patella Dislocation

A dislocation of the patella occurs when the patella comes completely out of its groove on the end of the thigh bone (femur), and comes to rest on the outside of the knee joint. Kneecap dislocations usually occur as a significant injury the first time the injury occurs, but the kneecap may dislocate much more easily thereafter.

2. Patella Fracture

A patella fracture is a break of the kneecap. The may results from trauma to the kneecap from accidents which impacts a severe blow to the knee or falling on the knee.

Patella fractures are diagnosed by the symptoms they present with including pain, swelling and difficulty or inability to walk. The condition can be confirmed with X-rays.

Patella fractures make up 1% of total bone fractures and are more common in males than females.

3. Patella Alta & Baja

These are conditions that results when the kneecap sits too high or too low. Patella alta or high-riding patella refers to an abnormally high patella in relation to the femur. The patella sits high on the femur where the groove is very shallow whereas Patella baja is a low-riding patella.

Types of Patella Surgery

patella surgery

There are number of surgical options on the kneecap and the method and procedure differs depending on the condition.

1. Realignment Surgery

This procedure is done on a dislocated kneecap and the aim is to realign the patella to its original position. Some procedures can be done using a minimally invasive technique where the surgeons makes use of an instrument known as arthroscope, an endoscope that is inserted into the joint through a small incision.

 Other procedures require open surgery. The kneecap can be realigned to improve its tracking. To do this, soft tissue and bone may be cut, tightened, or moved.

Surgical Techniques

Kneecap realignment surgery can be performed using a number of techniques.

i. Lateral Release

This involves releasing (cutting) the retinaculum so as to reduce the pull on the kneecap and thereby moving it into its proper place. The retinaculum is a band of tissue on both the inside and the outside of the kneecap that assists its motion. Releasing a plica band may also reduce pain. Plica bands are thick, fibrotic bands that may be found in several areas inside the knee joint.

ii. Quad Transfer

This procedure balances pull from the upper leg and is done through open surgery. Part of the muscle is detached. Then it is reattached at a new place on the kneecap.

2. Patellectomy

A patellectomy is a surgical procedure used to remove the entire or part of the patella and it is carried out to treat patella fractures.

A patellectomy can be either total (the entire kneecap is removed) or partial (only a certain part of it is removed).During a patellectomy, an incision is made into the quadriceps tendon and the patella is freed and removed. With this procedure, the patella tendon remains intact and partially functional.

Related: Types of Hip Surgery

Patella Surgery Risks and Complications

Like every other surgical procedure, kneecap surgery carries with it risk of complications including:

Infection – This occurs in less than 1% of patients and it is the most serious complication. The prosthetic joint may be invaded by bacteria and other disease-causing agents.

Signs of an infection are fever, chills, painful joint, and a draining sinus. Further diagnostics tests may be done to confirm the diagnosis. Contact your doctor immediately if develop any of the signs.

Deep vein thrombosis – This refers to the formation of a blood clot in a deep vein following the surgery and it occurs in 15% of patients. Symptoms may include pain, swelling and redness of the affected area.

Extension lag – the reduction in ability to straighten the leg fully

Increased laxity – The loss of the patella leaves the quadriceps tendon lax, and the knee prone to dislocation

Vulnerable femoral joint surface – As stated earlier, the essential function of the kneecap is to protect the surface of the knee joint. When the kneecap is removed as in patellectomy, without the protection of the bony patella, the important cartilage covering the end of the femur is easily damaged by knocks and falls.

Patella Surgery Recovery

As you recover, you can aid the healing process by taking it easy at first. Follow the instructions of your surgeon. Your knee may be bandaged, wrapped, or iced to keep swelling down. You may be given a brace to protect your knee. This helps improve your range of motion and speed healing. Keep your leg raised above your heart so fluid can drain away and swelling is reduced. Surgery is often followed by a rehabilitation or physical therapy program.

More: Knee Replacement Surgery