Central popliteal mass due to communicating posterior cruciate ligament cyst: an indication for a combined approach.

An isolated symptomatic posterior cruciate ligament cyst is uncommon, and extra-articular communication of this cyst is extremely rare. We report a case of a symptomatic communicating posterior cruciate ligament cyst presenting as a central popliteal mass. In view of the large extra-articular extension of this cyst and its close proximity to the popliteal neurovascular structures, we successfully treated this cyst with a combined arthroscopic and open approach.