Intra-articular knee cysts are most commonly found in the anterior and posterior cruciate ligaments. The etiology of cruciate ligament cysts, also known as cruciate tenosynovial cysts, is unclear and may be due to mucinous degeneration or cystic degeneration of the ligament. With the popularity of MRI, the number of cases of cruciate ligament cysts is gradually increasing. Diagnosis Primarily, there is limited knee flexion or extension activity with knee pain, usually without a history of trauma. Physical examination: Restricted knee flexion and extension activities are seen. Imaging MRI is the most useful adjunctive test and can clearly show the location and size of the cruciate ligament cyst. Treatment Minimally invasive arthroscopic surgery is the best way to treat cruciate ligament cysts in the knee joint. The cruciate ligament cyst can be completely removed arthroscopically with minimal trauma and the patient recovers quickly after surgery.