ELEVATED PLASMA FIBRONECTIN CONCENTRATIONS IN PATIENTS WITH OSSIFICATION OF THE POSTERIOR LONGITUDINAL LIGAMENT AND OSSIFICATION OF THE LIGAMENTUM-FLAVUM

Fibronectin is a glycoprotein involved in a wide variety of cellular a ctivities, including the development of bone tissues. To study the rel evance of fibronectin to the development of ossification of the poster ior longitudinal ligament (OPLL) and ossification of the ligamentum fl avum (OLF), plasma fibronectin concentrations in 30 consecutive patien ts with OPLL or OLF and 20 age-and-sex-matched control subjects were m easured with an immunonephelometric method. Plasma fibronectin concent rations were significantly elevated in the patients with OPLL or OLF, independently of associated endocrinologic abnormalities, when compare d with the control subjects. Because fibronectin is one of the essenti al factors in endochondral ossification, it is probable that the highe r fibronectin concentration in plasma acts as a promoter of the develo pment of OPLL and OLF.