Clinical History
64 year old female with posterior knee pain.
Diagnosis: Posterior Intercondylar Notch Ganglion Cyst Arising from the ACL
Ganglion cysts are common sources of pain and soft tissue mass that arise from areas of soft tissue injury, such as ligaments and the joint capsule.
In the knee, the ACL is a common source of ganglion cysts.
Ganglion cysts of the knee are easy to diagnose on MRI. On ultrasound, ganglion cysts located deep may be harder to confidently diagnose.
Ganglion cysts arising from the ACL, similar to those occurring elsewhere, may be amenable to ultrasound-guided aspiration and injection.
Because these ACL cysts tend to decompress posteriorly, the procedure is performed with the patient prone, and care must be taken to avoid the popliteal vessels and the tibial and common peroneal nerves.