Correlation between preoperative physical signs and functional outcomes after laminoplasty for ossification of the posterior longitudinal ligament

Background Ossification of the posterior longitudinal ligament (OPLL) can cause myelopathy that is often managed surgically. Knowledge of predictors of surgical outcomes can provide decision support to surgeons. The aims of this study were to investigate the relationships between preoperative physical signs and postoperative functional outcomes in patients with OPLL and to clarify whether physical signs could predict functional outcomes. Methods Fifty-five patients with OPLL who had undergone cervical laminoplasty were included in this study. Six physical signs including hyperreflexia, Babinski sign, sensory disturbance, grip strength, 10-s grip and release test, and bladder dysfunction, and four other factors including age, duration of symptoms, history of minor trauma and preoperative Japanese Orthopaedic Association (JOA) score were investigated as potential predictive prognostic factors using both univariate and multivariate analyses. Results The mean recovery rate of JOA score was 62.5 ± 32.5%. The neurological recovery rate was negatively associated with age (P = 0.002), the duration of symptoms (P = 0.002) and Babinski sign (P = 0.007), whereas it was positively correlated with grip strength (P = 0.011). Multiple logistic regression analyses revealed that age (Odds ratio: 0.89, 95% CI: 0.81–0.99) and Babinski sign (Odds ratio: 0.18, 95% CI: 0.04–0.89) were factors associated with functional outcomes. Conclusions Satisfactory functional outcomes could be expected for patients who are young and do not exhibit the Babinski sign, showing that the Babinski sign could be useful as an indicator of the window of opportunity for achieving satisfactory functional outcomes.