Synovial plicae (knee)

Synovial

plicae (knee) • Superior patellar plica - Ganzer Fall bei Radiopaedia

O'Donnell, C. Superior patellar plica. Case study, Radiopaedia.org. (accessed on 28 Oct 2022) https://doi.org/10.53347/rID-17139 • CC by-nc-sa 3.0 (modified)

Synovial

plicae (knee) • Infraction of the medial femoral condyle with hemarthrosis - Ganzer Fall bei Radiopaedia

Schubert, R. Infraction of the medial femoral condyle with hemarthrosis. Case study, Radiopaedia.org. (accessed on 28 Oct 2022) https://doi.org/10.53347/rID-17686 • CC by-nc-sa 3.0 (modified)

Synovial

plicae (knee) • Infrapatellar plica injury - Ganzer Fall bei Radiopaedia

Jha, P. Infrapatellar plica injury. Case study, Radiopaedia.org. (accessed on 28 Oct 2022) https://doi.org/10.53347/rID-18233 • CC by-nc-sa 3.0 (modified)

Synovial

plicae (knee) • Suprapatellar plica syndrome - Ganzer Fall bei Radiopaedia

Dixon, A. Suprapatellar plica syndrome. Case study, Radiopaedia.org. (accessed on 28 Oct 2022) https://doi.org/10.53347/rID-41239 • CC by-nc-sa 3.0 (modified)

An acquired

plica-induced notch in the medial femoral condyle in a patient with medial patellar plica syndrome: a case report. Preoperative axial (a) and sagittal (b) proton density-weighted images showing medial patellar plica (white arrows). c Idiopathic groove is observed in the articular surface of the medial femoral condyle (white asterisk). d Postoperative axial proton density-weighted image after excision of the medial patellar plica

bmcmusculoskeletdisord.biomedcentral.com • CC-by-4.0

An acquired

plica-induced notch in the medial femoral condyle in a patient with medial patellar plica syndrome: a case report. Intraoperative arthroscopic views. a Medial patellar plica (MPP) with a tight and hypertrophic margin is observed, along with an abnormal notch in articular surface of the medial femoral condyle beneath the MPP (black asterisk). b The MPP runs downwards and merges with the synovial membrane covering the infrapatellar fat pad. c The MPP becomes impinged in the patellofemoral joint above an abnormal notch of the medial femoral condyle (black asterisk). d The MPP is excised with scissor forceps

bmcmusculoskeletdisord.biomedcentral.com • CC-by-4.0

Radiopaedia • CC-by-nc-sa 3.0 • de

Synovial plicae are folds of synovium, thought to represent embryologic remnants. They are common, present in ~90% of arthroscopies .

They have been implicated in anterior knee pain and possibly in chondromalacia patellae although their role remains controversial .

Gross anatomy

Some plicae have been described with multiple names in the literature representing the same structure :

medial patellar plica: most common symptomatic plica
suprapatellar plica / superior patellar plica
infrapatellar plica / ligamentum mucosum: most common knee plica
lateral patellar plica: rare (<1%)

They range in shape from a ridge or shelf to more discrete cord-like structure .

Radiographic features

CT arthrography

Maybe seen as a shelf like band

MRI

PD/T2: typically seen as a band-like low signal structure traversing through the joint space (arthrography study or when joint effusion is present)