Submit Manuscript | http://medcraveonline.com Introduction Discoid medial meniscus was reported for frst time by Cave and Staples in 1941. 1 It is an extremely rare anomaly with an incidence of 0.1-0.3%. 2 Only 35 cases have been reported in literature so far. 3 We present a case report of a complete discoid medial meniscus associated with an anteromedial parameniscal cyst which was treated successfully by excision of the central anomalous part of the meniscus and cyst decompression. The discoid medial meniscus associated with a parameniscal cyst has not been described previously in the literature. Case report A 42 year old male consulted at arthroscopy and sports medicine institute because of right anteromedial knee pain on complete knee straightening and occasional limp and swelling on exertion. The pain was of 8 months duration, without any previous history of trauma, fall, either direct or indirect and was insidious in origin, and gradually progressive. There was occasional catching sensation especially on near complete knee extension. The pivoting activities was accompanied by pain and limp later and gradually progressed, affecting activities of daily living like prolonged standing ,sitting cross legged and squatting. The patient did notice fullness in the anteromedial region on exertion. There was no rest pain and no constitutional symptoms. Clinically, the medial joint line was tender and, Steinman II and Thessaly test were positive 4 (Figure 2). He had full range of motion with pain only on terminal extension localizing medially. The lachman, pivot shift was negative. Radiographs were seemingly normal with a fat medial plateau with MRI showing a bow-tie sign persisting in all sagittal images of medial meniscus with a grade 2 signal intensity (Figure 3). Arthroscopy confrmed an almost complete discoid medial meniscus with the free margin in contact with the ACL stump, without any evidence of abnormal attachment to ACL and medial tibial spine. The central anomalous portion of the discoid meniscus was excised arthroscopically revealing a horizontal cleavage. The cyst got decompressed once the mid segment and anterior segment junction was excised. A minimal yellow colored thick fuid was expelled during excision. Partial meniscectomy was completed leaving a well balanced peripheral rim. Post operatively the patient reported signifcant improvement in the VAS score from 8 to 1 (Figure 4). Physiotherapy was begun in immediate postoperative period and the recovery was good with no pain at the end of 1 week (VAS score 0) and patient did resume recreational sports after 1 month. MOJ Orthop Rheumatol. 2015;2(3):111‒113. 111 © 2015 Vishwakarma et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Pathognomic discoid medial meniscus with a parameniscal cyst: a case report and literature review of anomalous medial meniscus variants Volume 2 Issue 3 - 2015 Nilesh Vishwakarma, Abhishek Kini, Anant Joshiz, Julio Gali Pontifcal Catholic University of Sao Paulo, Brazil Correspondence: Nilesh Vishwakarma, Pontifcal Catholic University of Sao Paulo, Rua Caracas, Sorocaba,Sao Paulo, Brazil, Tel 32334171, Email Received: February 22, 2015 | Published: April 8, 2015 Abstract Discoid medial meniscus is an extremely rare anomaly with an incidence of 0.1-0.3%. Only 35 cases have been reported in literature so far. The association of a Parameniscal cyst with a discoid medial meniscus has been not described in literature to our knowledge. The cyst related to the discoid medial meniscus was anteromedial in location as compared to the lateral discoid meniscus cyst which usually is in lateral or postero-lateral in position. We present a case report of a complete discoid medial meniscus with a parameniscal cyst which was treated successfully by excision of the central anomalous part of the meniscus and cyst decompression. The presentation differs drastically as compared to a discoid lateral meniscus and the age of presentation is also not defned due to rarity of such cases. The discoid medial meniscus developed a horizontal cleavage tear and consequently a parameniscal cyst which became symptomatic insidiously. Physical examination revealed medial joint line tenderness with Thessaly test and Steinman II tests positive (Figure 1). Controversy exists with regards to the etiology of discoid medial meniscus wherein Kaplan in 1974 stated that congenital alteration in the attachment of posterior horn of the meniscus by the meniscofemoral ligament which becomes hypermobile and Smillie postulated that menisci exist as cartilaginous disc at an early stage in development and congenital discoid meniscus is attributable to persistence of the disc shape at varying stages of embryonic development. Various anomalies reported include anterior horn hypoplasia, anomalous posterior horn attachment to lateral femoral condyle, anomalous insertion of anterior horn to ACL, anterior transportation of the anterior medial meniscus below the anterior edge of the tibial plateau and the anterior horn contiguous with the ACL, increased tibial plateau concavity with elongated medial tibial spine and lastly bilateral occurance. Keywords: discoid, medial, meniscus MOJ Orthopedics & Rheumatology Case Report Open Access