What is a Medial Patellofemoral Ligament Injury?
The medial patellofemoral ligament (MPFL) is a ligament that joins the kneecap (patella) to the thighbone (femur). Ligaments are fibrous connective tissue that attach bones to other bones. The MPFL is attached to the inside of the patella and helps stabilize it and position it in a groove at the lower end of the femur called the trochlea. Trauma or a blow to the knee may cause a tear in the ligament.
Causes of Medial Patellofemoral Ligament Injury
An MPFL injury may occur due to knee injuries causing patellar dislocation or forceful twisting. This can occur due to:
- Sports injuries
- Automobile accidents
- Falls from a height
- A blow to the knee
Symptoms of Medial Patellofemoral Ligament Injury
Symptoms of a medial patellofemoral ligament injury include:
- Recurrent patella instability or dislocations
- Knee stiffness
- Swelling
- Pain
- Tenderness
- Catching sensation on bending and straightening the knee
- Difficulty walking
- Cracking or crunching sound
- Restricted range of motion
- Discolouration near the injured area
- Bruising
Diagnosis of Medial Patellofemoral Ligament Injury
Your doctor will review your medical history and perform a physical examination where the knee and patella are assessed for range of motion, strength, and stability. Your doctor may also recommend imaging tests such as X-rays, CT scans, or an MRI scan to visualize the ligament injury and any damage to other structures.
Treatment for Medial Patellofemoral Ligament Tears
Treatment measures for medial patellofemoral ligament tears include:
Conservative methods
- RICE Method: Your doctor will recommend rest, ice application, compression, and elevation of the affected knee to reduce inflammation and pain.
- Physical therapy: You will be instructed to carry out physical exercises to strengthen the knee muscles and improve flexibility
- Medications: Non-steroidal anti-inflammatory drugs and analgesics are recommended to treat pain and swelling.
- Knee brace: A brace may help support the knee.
- Special Footwear: This can help control your gait while walking or running and decrease the pressure on the kneecap.
If conservative methods failed to improve the symptoms, surgery will be recommended and may include:
- Medial patellofemoral ligament reconstruction: The torn MPFL is reconstructed using a graft (usually a single hamstring tendon) which is fixed to the patella and femur using small screws. The grafts are either taken from your own body (autograft) or a donor (allograft).
- Tibial tubercle osteotomy: Changing the insertion point of the patellar tendon to improve patellar alignment.
- Lateral release: The tight lateral ligaments of the kneecap are released to correct the patella position.
- Trochleoplasty: Reshaping the groove or trochlea at the lower end of the femur helps with positioning and smooth movement of the patella.