Risk factors for disc height loss in conservatively treated symptomatic lumbar disc herniation in elderly patients

Lumbar disc herniation, which causes low back pain and radiating pain in the lower extremities, is a common disease that occurs in 20% to 30% of the population [1]. Since Mixter and Barr introduced surgical treatment for lumbar disc herniation in 1934, discectomy has been performed as standard treatment for this disease [2]. However, it has been reported that the lumbar disc herniation-induced low back pain and radiating pain in the lower extremObjective: The purpose of this study was to evaluate the clinical and radiologic factors associated with disc height loss in patients with spontaneous resolution of lumbar disc herniation. Methods: In total, 56 symptomatic herniated lumbar disc patients above 65 years old (36 male and 20 female patients) who received conservative treatment from January 2017 to December 2018 were retrospectively investigated. Clinical findings including age, sex, pain, and smoking history were examined in each group (group A, patients with unchanged disc height; group B, patients with decreased disc height). As radiologic findings, the level, severity, laterality, Modic changes, and disc degeneration of lumbar disc herniation were investigated and compared between groups. Results: Group A contained 30 patients and group B comprised 26 patients. No statistically significant differences were found in age, sex, visual analogue scale scores, level of disc herniation, and laterality of disc herniation between groups. Group A had more protrusion cases (14/30 cases) and group B had more sequestration (11/26 cases). Group B had more cases of Modic changes and more disc degeneration cases than group A. Conclusion: In patients who receive conservative treatment for symptomatic lumbar disc herniation, disc height loss may occur later, especially in cases of extrusionand sequestration-type herniation. This disc height decrease after lumbar disc herniation without surgical removal of the disc may occur due to disc degeneration and disc herniation itself. Patients who are treated conservatively should receive an explanation that disc height may be reduced later.