The impact of postoperative cervical sagittal alignment on patient-reported outcomes following posterior decompression and fusion for degenerative cervical myelopathy: A prospective cohort study with 18 month follow-up.

内容摘要

Degenerative cervical myelopathy (DCM) is a leading cause of nontraumatic spinal cord dysfunction. While posterior cervical decompression and fusion (PCDF) effectively improves neurological symptoms, persistent axial neck pain remains a common postoperative challenge. This prospective study evaluated the impact of postoperative cervical sagittal alignment on achieving the minimal clinically important difference (MCID) for axial neck pain eighteen months following PCDF for DCM. We conducted a single-center prospective cohort study including adult patients undergoing primary PCDF for DCM. Comprehensive clinical and radiographic data were collected preoperatively and at multiple postoperative intervals up to eighteen months. Key radiographic parameters evaluated included C2-C7 sagittal vertical axis (SVA), cervical lordosis (CL), and T1 slope minus cervical lordosis (TS-CL) mismatch. Multivariable logistic regression was utilized to identify independent predictors for achieving MCID. Fifty-five patients were included, with a mean follow-up of 20.4 months. Twenty-four patients (43.6%) successfully achieved MCID for axial neck pain. The MCID cohort exhibited significantly lower postoperative C2-C7 SVA, greater CL, and a smaller TS-CL mismatch. Multivariable analysis demonstrated that increased postoperative SVA and active opium addiction independently reduced the odds of achieving MCID. Furthermore, patients with "balanced" postoperative alignment (C2-C7 SVA < 40&#x202f;mm and TS-CL < 15&#xb0;) demonstrated significantly superior improvements in Visual Analog Scale (VAS) pain, Neck Disability Index (NDI), and modified Japanese Orthopedic Association (mJOA) scores. Postoperative cervical sagittal balance is a critical determinant of patient-reported outcomes and neurological recovery after PCDF. Minimizing postoperative SVA and addressing TS-CL mismatch significantly increases the likelihood of achieving clinically meaningful relief of axial neck pain and improves overall functional recovery.