Ten-Year Follow-up of Posterior Decompression and Fusion Surgery for Thoracic Ossification of the Posterior Longitudinal Ligament

Background: We evaluated the clinical, functional, and quality of life (QoL) outcomes of surgical treatment of thoracic ossification of the posterior longitudinal ligament (T-OPLL). Methods: We retrospectively evaluated 51 patients followed for >= 10 years after posterior decompression and corrective fusion surgery for T-OPLL. The data collected included demographics, comorbidities, and pre- and postoperative symptoms. The Japanese Orthopaedic Association (JOA) score, numerical rating scale (NRS) for back and leg pain, and EuroQol-5 Dimension-5 Level (EQ-5D-5L) were used to assess neurological function, pain, and QoL. Imaging evaluations were conducted to assess changes in kyphotic angles and ossification progression. Results: A significant improvement was observed in the JOA score from preoperatively (3.7) to 2 years postoperatively (7.9) (p < 0.05); the score remained stable thereafter. The mean EQ-5D-5L score improved from 0.53 preoperatively to 0.68 at 10 years postoperatively (p < 0.001). NRS scores for back and leg pain decreased from 5.4 to 3.5 and 4.0 to 3.0, respectively, from preoperatively to 10 years (p < 0.001 for both). Radiographic outcomes showed changes in kyphotic angles and ossification areas, with no significant progression after 2 years. Fourteen (27.5%) of the patients experienced postoperative complications. Of these, 8 (15.7%) required reoperation, 6 (11.8%) in the perioperative period and 2 (3.9%) later. Four (7.8%) of the patients underwent additional surgeries for conditions including lumbar spinal canal stenosis and cervical OPLL. Nonetheless, physical function in all cases with postoperative complications or additional surgery remained stable over the decade. Conclusions: Surgical treatment of T-OPLL is effective in improving neurological function, QoL, and pain management over an extended period. The long-term outcomes of T-OPLL surgery revealed that, although cervical and lumbar spinal lesions led to reoperations, they did not affect QoL, and relative improvement was maintained even after 10 years.