Endemic fluorosis and its impact on cases of cervico-dorsal ossification of the posterior longitudinal ligament

Objectives: This study has been centered in the state of Rajasthan, to consolidate the significance of high fluoride consumption and endemicity in causing ossification of the posterior longitudinal ligament (OPLL) and tries to identify fluorosis as a predictor of operative as well as post-operative outcome. Materials and Methods: A single-center retrospective cohort study. Case records of clinico-radiologically diagnosed patients of OPLL were retrospectively evaluated who were managed during a three-year duration (2019–2022). Patients were grouped into Group A: Endemic zone; ground water consumption, Group B: Endemic zone; purified water consumption and Group C: Patients from non-endemic region. Nurick grade and modified Japanese Orthopedic Association (mJOA) scores were used for clinical evaluation. Demographic, clinical, radiological, management, and urinary fluoride were evaluated preoperatively, at discharge, and after three months. Results: Of the total operated 28 patients, 23 belonged to the fluorosis endemic zone whereas 5 were from a non-endemic zone. Group A showed deterioration in Nurick as well as mJOA scores P < 0.05 in the follow-up period. Group C patients showed the best improvement postoperatively followed by Group B. Fluorosis had an impact as an independent variable for clinical outcome, but it was not found to be clinically significant. Conclusion: Early outcomes of OPLL with fluorosis appear to have a higher risk of deterioration after surgery in comparison to those who are from non-endemic zones or have no fluorosis.