An Evaluation of the Facet Joint Angle Characteristics on the Development of Lumbar Disc Hernia in Young Patients

Background: The aim of the current study was to investigate facet tropism in young patients with lumbar disc hernia (LDH) and the role of facet tropism in the development of LDH. Methods: The study included 57 patients aged 20-32 years with a diagnosis of LDH and bilateral facet joint angles at L3-4, L4-5 and L5-S1 levels measured on lumbar magnetic resonance imaging (MRI) tests. In the comparison of the two facet joint angles, a difference of <7° was classified as no tropism, 7°-14° as moderate tropism and >14° as severe tropism. A control group was formed of 46 age-matched healthy individuals with no lumbar disc hernia. Results: A total of 618 facet facet angles were measured, comprising 342 in the 57 patients in the LDH group and 276 in the 46 subjects of the control group. In the LDH group, at the L3-4 level, no tropism was determined in 46 (80.7%), moderate tropism in 9 (15.7%) and severe tropism in 2 (3.5%). At the L4-5 level, no tropism was determined in 36 (63.1%), moderate tropism in 17 (29.8%) and severe tropism in 4 (7%). At the L5-S1 level, no tropism was determined in 33 (57.9%), moderate tropism in 17 (29.8%) and severe tropism in 7 (12.2%).In the control group, at the L3-4 level, no tropism was determined in 40 (87%), moderate tropism in 5 (10.9%) and severe tropism in 1 (2.2%). At the L4-5 level, no tropism was determined in 37 (80.4%), moderate tropism in 8 (17.3%) and severe tropism in 1 (2.1%). At the L5-S1 level, no tropism was determined in 34 (73.9%), moderate tropism in 7 (15.2%) and severe tropism in 5 (10.9%). In the LDH group, the mean facet angle values were 40.4° at L3-4, 42.7° at L4-5 and 45.9° at L5-S1 levels. In the control group, the mean facet angle values were 39.2° at L3-4, 41.4° at L4-5 and 43.9° at L5-S1 levels. Conclusion : Although facet joint tropism was seen at a higher rate in the LDH patients than in the control group, the difference was not statistically significant (p>0.05). The results of the study did not suggest that facet tropism is a factor in the etiology of LDH.