Painfull Posterior Cruciate Ligament Ganglion Cyst. A Case Report

Abstract

Ganglion cysts (GC) are benign tumor-like lesions usually going out from mucinous degeneration of collagenous structures [1,2]. They could occur in several anatomic areas but GC arising from cruciate ligaments are rare [3,4] with a prevalence of 0.36% or 0.8% respectively when diagnosed by magnetic resonance (MR) or by arthroscopy [3,5-6] However other studies of GC prevalence refer ranges from 0.2% to 1.9% [7-9], with posterior cruciate ligament ganglion cysts (PCLGC) being five times less frequent than those identify in anterior cruciate ligament [5,10]. This lesion is mainly diagnosed in people aged 20-40 years-old and a male predominance has been reported [5,11-13]. The etiology of PCLGC is not clear. They could appear from synovial herniation or congenital translocation of synovial cells. Mesenchymal stem cells proliferation with cysts formation or mucoid degeneration occurring in areas suffering chronic injuries are also reported [7,14-16]. Many of PCLGC are asymptomatic. When symptomatic the main clinical symptoms and signals includes knee pain and / or movement restrictions [17]. The knee joint could present a slight effusion, restriction to extension and particularly in extreme flexion [1,4]. The common classification of cruciate ligament cysts is supported on the position of the cyst, anterior, posterior or between cruciate ligaments [7]. MR is the gold standard for detecting GC1. Recently observation by ultrasonography is considered useful for identifying and locating the lesion, as well as being a conservative approach to treat cystic lesions [1].