Trauma from ligamentous, osseous or meniscal injuries can result in an effusion. The majority of medial knee injuries are isolated ligamentous injuries. In this situation there is an absence of osseous and ligamentous structures. If muscular control does not compensate for ligamentous laxity, joint instability may result. Someone with ligamentous laxity, by definition, has loose ligaments. The sacroiliac joint is highly dependent on its strong ligamentous structure for support and stability. The Aryepiglottic folds are triangular folds of mucous membrane enclosing ligamentous and muscular fibres. This deformity is more common in women and people with familial ligamentous laxity. In connection with the stylohyoideus muscle, a ligamentous band, the stylohyoid ligament, may be described. In addition, ligamentous laxity may appear in conjunction with physical co-ordination conditions such as Dyspraxia. Cycling has to be avoided in people having ligamentous laxity. This ligamentous attachment ensures that the proximal fragment remains in its correct anatomical position. Grade III injuries have a complete ligamentous tear. The ligamentous structures offer resistance to shear and loading. The function of the ligamentous system is guiding and constraining certain patterns of motion.