Study Design.
Retrospective cohort study.
Objective.
To elucidate the postoperative time course of improvements in physical and mental well-being in patients with cervical spondylotic myelopathy (CSM).
Summary of Background Data.
Spinal surgeons should understand the postoperative course in detail. However, data are still needed regarding the time course of improvements in well-being, a fundamental aspect of human life, after cervical surgery for CSM.
Methods.
One hundred consecutive patients who underwent laminoplasty for CSM, with complete clinical data preoperatively and 3 months and 2 years postoperatively, were enrolled. The Short Form-36 physical component summary (PCS) and mental component summary (MCS) scores were used as parameters of physical and mental well-being, respectively, and 4.0 was defined as the minimal clinically important difference (MCID) for both parameters.
Results.
On average, PCS and MCS scores were significantly improved after surgery (P < 0.001, P=0.004, respectively). Moreover, 64 and 48 patients achieved meaningful improvement (>MCID) in PCS and MCS scores at 3 months postoperatively, with maintained improvement (to 2 yr) in 46/64 (71.9%) and 34/48 patients (70.8%), respectively (PCS vs. MCS: P = 0.912). Additionally, 15 of 36 patients (41.7%) and 8 of 52 patients (15.4%) achieved late improvement (meaningful improvement at 2 yr but not at 3 months) in PCS and MCS scores, respectively (PCS vs. MCS: P = 0.007). In multivariate regression analysis, improvement in cJOA score was significantly associated with PCS improvement, but not MCS improvement, at both 3 months and 2 years (P = 0.001, P > 0.001, respectively).
Conclusion.
The overall outcome of physical well-being improvement is decided within 3 months postoperatively, in proportion to the recovery in myelopathy, with a relatively high chance of meaningful improvement over the next 21 months. The outcome of improvement in mental well-being is decided within 3 months postoperatively, independently from the recovery in myelopathy, with a low chance of meaningful improvement over the next 21 months.
Level of Evidence: 3