Clinical outcomes of nonambulatory patients caused by ossification of the ligamentum flavum in the thoracic spine.

OBJECTIVE

Thoracic ossification of the ligamentum flavum (T-OLF) may lead to severe thoracic myelopathy and loss of ambulation. Limited data are available regarding surgical outcomes in patients who are nonambulatory preoperatively. This study aimed to evaluate the surgical outcomes of posterior decompression in nonambulatory patients with T-OLF and to identify factors associated with failure to regain ambulation.

METHODS

This retrospective study included consecutive patients with T-OLF who were nonambulatory before surgery and underwent posterior decompression with fusion (PDF) between July 2010 and July 2023. Preoperative nonambulatory status was defined as complete loss of walking ability, including inability to walk with assistive devices. Neurological function was assessed using the thoracic-adapted modified Japanese Orthopaedic Association (mJOA) score (maximum 11 points). Postoperative ambulation was defined as the ability to walk independently or with assistive devices. Patients were divided into ambulatory and nonambulatory groups based on walking status at the final follow-up. Multivariable logistic regression was performed to identify predictors associated with persistent nonambulation after surgery.

RESULTS

A total of 72 patients with a minimum 2-year follow-up were included. At final follow-up, 58 patients (80.6%) regained ambulatory function, whereas 14 patients (19.4%) remained nonambulatory. The mean mJOA score improved significantly after surgery (p < 0.001), with a median recovery rate of 47.2%. Female sex (OR 4.51, p = 0.032) and lower preoperative mJOA score (OR 0.46, p = 0.006) were independently associated with failure to regain ambulation after surgery.

CONCLUSIONS

In patients with T-OLF who were nonambulatory preoperatively, PDF resulted in recovery of ambulation in the majority of cases. Female sex and lower preoperative neurological function were associated with reduced likelihood of regaining ambulation. Even in severe thoracic myelopathy, meaningful functional improvement remains achievable following surgical decompression.