A new arthroscopic technique for lateral parameniscal cyst decompression

The purpose of this study was to describe an arthroscopic technique for lateral parameniscal cyst (LPC) decompression with preservation of meniscal substance and to report the short- to mid-term outcome of 20 patients.

All patients underwent a complete physical examination and magnetic resonance imaging (MRI) of the knee prior to surgery. After arthroscopic diagnosis of a LPC, partial lateral meniscectomy was performed via anterolateral (AL) and anteromedial (AM) portals. For LPC treatment, we used AL and superomedial (SM) portals. We describe a SM portal at the most proximal part of suprapatellar pouch, just medial to quadriceps tendon for the arthroscope. To decompress the cyst, an intra-articular (IA) portal was created with a shaver on the anterior synovial wall of the cyst from the AL portal. Decompression was performed via the AL portal and through the IA portal under the view of the arthroscope in the SM portal in SM portal. At the last follow-up, Lysholm score was used, and patients' clinical outcomes were classified into four categories: excellent, good, acceptable, and poor. Additionally, during the last control, patients underwent an MRI which was assessed for recurrence.

Mean follow-up period was 37.5±18.8 months. Clinical outcomes were excellent in 15 patients, good in four, and fair in one. The mean Lysholm score was 96.2±7.59. No recurrence of the cyst was seen on control MRIs.

Arthroscopic LPC decompression with superior and anterior portals is a novel, safe, and effective technique for experienced surgeons. It allows conservation of meniscal tissue, easier handling of instruments, and provides an excellent view of the cyst.