Table 2. Differential diagnoses for knee synovial plica syndrome.

• OCD

• Meniscus pathology

• Patella femoral subluxation

• Hoffa fat pad syndrome

• Osteoarthritis of the knee; this can often coexist with SPS

• Chondromalacia

• Inflammatory arthropathy of the knee; this may coexist with SPS (look for features of systemic disease as well as joint-specific symptoms)

• Snapping ITB syndrome; this may coexist with SPS, usually on the lateral side

• Ligament instability, such as ACL, MCL

• Chondromatosis

• PVNS

• Patella tendinosis

Abbreviations: ACL, anterior cruciate ligament; ITB, iliotibial band; MCL, medial collateral ligament; OCD, osteochondritis dissecans; PVNS, pigmented villonodular synovitis; SPS, synovial plica syndrome.