Patellofemoral Instability

What is patellofemoral instability?

An unstable kneecap is referred to as patellar instability. The kneecap (patella) shifts from its natural position in the groove at the end of the thigh bone (femur). The trochlear groove, a V-shaped notch on the kneecap, glides up and down as you bend and straighten your knee. The kneecap doesn't fit properly in the groove when there is patellofemoral instability. As a result, the condition causes knee joint discomfort, swelling, and a sense of instability. A dislocated knee may result from an unstable kneecap.

What causes patellofemoral instability?

Several causes contribute to patellofemoral instability, such as:

  • Anatomic abnormalities - The patella's motion and tracking can be impacted by specific structural anomalies in the knee joint, which can cause instability. For instance, a tilted patella or a shallow trochlear groove can increase the risk of the patella
  • Genetic factors - There may be a familial history of patellofemoral instability in some cases, and the disorder itself may be inherited.
  • Overuse - The muscles that support the patella might become weak or unbalanced as a result of repetitive stress on the knee. The patella may migrate out of place more frequently due to this.
  • Trauma - Patellofemoral instability may occur after a severe injury, such as a fall or a blow to the knee. This could result from injury to the knee joint's supporting ligaments, tendons, or muscles.
  • Other factors - Other conditions, such as tight muscles, hypermobile joints, and neuromuscular diseases, may also cause instability in the patellofemoral joint.

What are the signs of patellofemoral instability?

Depending on the severity of the condition, patellofemoral instability symptoms might vary. However, typical symptoms include the following:

  • A cracking or grinding sound when bending the knee
  • Knee joint instability or weakness
  • Knee joint swelling or irritation
  • Patella-specific discomfort or pain, particularly during physical exercise or after extended sitting
  • Recurrent subluxations or dislocations of the patella
  • Restricted range of motion or knee stiffness
  • The sensation that the knee is giving way or buckling
  • Walking or carrying weight on the afflicted limb is difficult.

These signs and symptoms could be slight or severe, sporadic or ongoing. It is crucial to seek a medical examination with Dr van Niekerk if you are exhibiting any of these symptoms to identify the source of your knee discomfort and obtain the proper care.

How does Dr van Niekerk check for patellofemoral instability?

Dr van Niekerk will perform a physical examination and look for instability in the patient's knee, such as excessive lateral patellar mobility or discomfort along the medial or lateral patellar border. To assess the stability of the patella, he might also carry out additional tests, such as apprehension or gliding. Dr van Niekerk will examine your physical abilities and measure your range of motion. Imaging tests like X-rays, MRIs, or CT scans could be prescribed to examine the architecture of the knee joint, spot any structural issues or damage to the bones, ligaments, or tendons, and confirm the patellofemoral instability diagnosis. Further procedures such as nerve conduction studies or electromyography (EMG) may occasionally be prescribed to assess the function of the nerves and muscles.

How do you treat patellofemoral instability?

Treatment options may include:

  • Activity modification may be advised to limit knee-stressing activities to lessen the chance of patellar instability.
  • Bracing – In order to assist in maintaining the patella's position and lowering the risk of dislocation, a knee brace or other supportive device may be advised.
  • Medication - Over-the-counter painkillers or anti-inflammatory drugs may be suggested to control pain and swelling. Dr van Niekerk can also prescribe the necessary medications.
  • Physiotherapy - Exercises targeting the knee muscles can assist in increasing patellar stability and alignment.
  • Surgery - Surgery may occasionally be required to rectify anatomical defects or mend torn ligaments, tendons, or muscles.


What are the surgical options for patellofemoral instability?

Some standard surgical procedures that Dr van Niekerk performs include:

  • Cartilage restoration procedures
  • Lateral release
  • Medial patellofemoral ligament (MPFL) reconstruction
  • Realignment procedures
  • Tibial tubercle osteotomy
How long does patellofemoral instability surgery take?

Dr van Niekerk can perform most patellofemoral instability procedures with minimally invasive methods in 1-2 hours. However, a surgery that involves realigning the bones or restoring damaged cartilage may be more complex and take longer.

Does it take longer to heal after surgery for patellofemoral instability?

It can take several months to heal, and it might even take a year or longer to recover fully.