Fact Checked
Patellofemoral instability is characterized by a sensation that the kneecap is slipping away or feels loose during movement. The instability might be linked with pain and swelling in the anterior part of the knee and categorized into 2 main groups – primary and secondary.
Primary patellofemoral instability
This form of instability can develop from a variety of mechanisms such as:
- Laxity of the ligaments surrounding the knee.
- The position of the patella might be too elevated inside the joint.
The bony prominence or tibial tuberosity at the front and upper part of the tibia might be positioned anatomically towards the exterior or lateral surface of the tibia. - The bony prominence or tibial tuberosity at the front and upper part of the tibia might be positioned anatomically towards the exterior or lateral surface of the tibia.
Management
The treatment for this type of patellofemoral instability might be non-surgical or surgical:
- Non-surgical – if the joint is inflamed and aching, a knee extension brace is used to restrain movement of the knee. Strengthening of the quadriceps might be recommended as well. Taping techniques are also beneficial in correcting the patellar tracking.
- Surgery – in some cases, surgery is required to fix the alignment of the patella. This might involve the lateral release of the retinaculum and other muscle fibers.
Secondary patellofemoral instability
This form usually stems from a primary knee dislocation. It is important to note that the medial patellofemoral ligament is responsible for stabilizing the patella to prevent it from shifting laterally. During a dislocation, the structure might be significantly compromised which results to instability.
Management
- Non-surgical – a knee extension brace is used if knee pain and swelling is present for immobilization. Strengthening of the quadriceps is also recommended as well as taping to correct patellar tracking.
- Surgery – this involves fixing the medial patellar ligament if severely torn