Popliteal cyst

Background

• Also known as Baker's cyst
• Develops posteriorly and inferiorly to the knee as herniation of the synovial membrane of the knee capsule
• The cyst communicates with the knee joint and is the leading cause of posterior knee pain

Clinical Features

• Pain/swelling of posterior knee

Differential Diagnosis

Knee diagnoses

Acute knee injury

• Knee dislocation
• Knee fractures
  • Patella fracture
  • Segond fracture
  • Tibial plateau fracture
• Meniscus and ligament knee injuries
• Patella dislocation
• Patellar tendonitis
• Patellar tendon rupture
• Quadriceps tendon rupture

Nontraumatic/Subacute

• Arthritis
• Gout and Pseudogout
• Osgood-Schlatter disease
• Patellofemoral syndrome (Runner's Knee)
• Patellar tendonitis (Jumper's knee)
• Pes anserine bursitis
• Popliteal cyst (Bakers cyst)
• Prepatellar bursitis (nonseptic)
• Septic bursitis
• Septic joint
• DVT

Calf pain

• Achilles tendon rupture
• Calcaneal bursitis
• Cellulitis
• Compartment syndrome
• Deep venous thrombosis (DVT)
• Distal leg fractures
• Gastrocnemius strain
• Ruptured popliteal cyst (Bakers cyst)
• Superficial thrombophlebitis

Evaluation

Baker's cyst on MRI, sagittal image

• Ultrasound

Management

• Treatment is conservative; excision may be required in some cases

Disposition

• Discharge

See Also

• Knee (Minor)