The retinaculum is a fine but strong sheet of fibrous tissue communicating on both sides of the knee between the patella and the muscles and other supportive structures around the knee.
Patellofemoral ligaments
The retinacula (plural) are distinct from the medial and lateral patellofemoral ligaments.
Medial and lateral "....[p]atellofemoral ligaments and retinacula are separate structures macroscopically and in imaging....The retinacula....[have]....a higher nerve fibre content and higher number of elastic fibres compared to the ligaments."
Is the patellar retinaculum important?
The patellar retinaculum is an important stabiliser of the patella.
During a traumatic patella dislocation event, the retinaculum may become damaged, together with the medial patellofemoral ligament (MPFL). Such damaged supports may allow the patella to chronically sublux.
....Lateral retinaculum tightness is assessed with the patellar glide test. The knee is flexed 20-30⁰, the quadriceps is relaxed, and the patella is pushed medially. Medial displacement less than one-fourth of the patellar width is indicative of a tight lateral retinaculum...."
What is a lateral retinacular release?
A lateral retinacular release is a surgical procedure performed in patients who are suffering from excessive lateral pressure syndrome, where the patellar cartilage is under stress due to tight structures on the lateral side.
It has proven important that this procedure should only be done for very specific indications, and should be avoided if there has been any previous episode of patellar instability.
....Surgeons should bear in mind that lateral retinaculum tightness should be diagnosed with caution, since inconsiderate lateral retinacular release (LRR) may lead to iatrogenic medial patellar instability...."
Relevant links on KNEEguru
A-Z Keywords
MPFL, Dislocation of the patella, Lateral retinaculum, Lateral release, Lateral retinacular lengthening
Forum discussions
- Lateral release made by mistake: is there a way to fix it? - A very full thread of discussions about lateral retinacular release surgery.