Impact of Myelopathy Severity and Degree of Deformity on Postoperative Outcomes in Cervical Spinal Deformity Patients

Objective Malalignment of the cervical spine can result in cord compression, leading to a myelopathy diagnosis. Whether deformity or myelopathy severity is stronger predictors of surgical outcomes is understudied. Methods Surgical cervical deformity (CD) patients with baseline (BL) and up to 1-year data were included. Modified Japanese Orthopaedic Association (mJOA) score categorized BL myelopathy (mJOA = 18 excluded), with moderate myelopathy mJOA being 12 to 17 and severe myelopathy being less than 12. BL deformity severity was categorized using the mismatch between T1 slope and cervical lordosis (TS-CL), with CL being the angle between the lower endplates of C2 and C7. Moderate deformity was TS-CL less than or equal to 25° and severe deformity was greater than 25°. Categorizations were combined into 4 groups: group 1 (G1), severe myelopathy and severe deformity; group 2 (G2), severe myelopathy and moderate deformity; group 3 (G3), moderate myelopathy and moderate deformity; group 4 (G4), moderate myelopathy and severe deformity. Univariate analyses determined whether myelopathy or deformity had greater impact on outcomes. Results One hundred twenty-eight CD patients were included (mean age, 56.5 years; 46% female; body mass index, 30.4 kg/m2) with a BL mJOA score of 12.8±2.7 and mean TS-CL of 25.9°±16.1°. G1 consisted of 11.1% of our CD population, with 21% in G2, 34.6% in G3, and 33.3% in G4. At BL, Neck Disability Index (NDI) was greatest in G2 (p=0.011). G4 had the lowest EuroQol-5D (EQ-5D) (p<0.001). Neurologic exam factors were greater in severe myelopathy (p<0.050). At 1-year, severe deformity met minimum clinically important differences (MCIDs) for NDI more than moderate deformity (p=0.002). G2 had significantly worse outcomes compared to G4 by 1-year NDI (p=0.004), EQ-5D (p=0.028), Numerical Rating Scale neck (p=0.046), and MCID for NDI (p=0.001). Conclusion Addressing severe deformity had increased clinical weight in improving patient-reported outcomes compared to addressing severe myelopathy.

[1]  Jen-Hung Wang,et al.  Two surgical strategies for treating multilevel cervical spondylotic myelopathy combined with kyphotic deformity , 2020, Medicine.

[2]  F. Schwab,et al.  Minimal Clinically Important Difference and Substantial Clinical Benefit Using PROMIS CAT in Cervical Spine Surgery , 2019, Clinical spine surgery.

[3]  D. Hoh,et al.  Cervical Spine Deformity Correction Techniques , 2019, Neurospine.

[4]  Jared C. Tishelman,et al.  McGregor's slope and slope of line of sight: two surrogate markers for Chin-Brow vertical angle in the setting of cervical spine pathology. , 2019, The spine journal : official journal of the North American Spine Society.

[5]  Justin K Scheer,et al.  Recovery kinetics following spinal deformity correction: a comparison of isolated cervical, thoracolumbar, and combined deformity morphometries. , 2019, The spine journal : official journal of the North American Spine Society.

[6]  Jun S. Kim,et al.  Cervical Spine Deformity: Indications, Considerations, and Surgical Outcomes. , 2019, The Journal of the American Academy of Orthopaedic Surgeons.

[7]  L. Lenke,et al.  Novel radiographic parameters for the assessment of total body sagittal alignment in adult spinal deformity patients. , 2019, Journal of neurosurgery. Spine.

[8]  Justin K Scheer,et al.  Outcomes of Operative Treatment for Adult Cervical Deformity: A Prospective Multicenter Assessment With 1-Year Follow-up , 2018, Neurosurgery.

[9]  Alan H. Daniels,et al.  The Relationship Between Improvements in Myelopathy and Sagittal Realignment in Cervical Deformity Surgery Outcomes , 2018, Spine.

[10]  M. Fehlings,et al.  Impact of Cervical Spine Deformity on Preoperative Disease Severity and Postoperative Outcomes Following Fusion Surgery for Degenerative Cervical Myelopathy: Sub-analysis of AOSpine North America and International Studies , 2017, Spine.

[11]  Zhanchun Li,et al.  Surgical treatment for cervical spondylotic myelopathy in elderly patients: A retrospective study , 2015, Clinical Neurology and Neurosurgery.

[12]  E. Benzel,et al.  Relationship between degree of focal kyphosis correction and neurological outcomes for patients undergoing cervical deformity correction surgery. , 2013, Journal of neurosurgery. Spine.

[13]  R. Laing,et al.  Measurement of long-term outcome in patients with cervical spondylotic myelopathy treated surgically , 2002, European Spine Journal.

[14]  Justin K Scheer,et al.  The Impact of Standing Regional Cervical Sagittal Alignment on Outcomes in Posterior Cervical Fusion Surgery. , 2012, Neurosurgery.

[15]  J. Cleland,et al.  Reliability, Construct Validity, and Responsiveness of the Neck Disability Index, Patient-Specific Functional Scale, and Numeric Pain Rating Scale in Patients with Cervical Radiculopathy , 2010, American journal of physical medicine & rehabilitation.

[16]  L. Bouter,et al.  Minimal Clinically Important Change of the Neck Disability Index and the Numerical Rating Scale for Patients With Neck Pain , 2007, Spine.

[17]  J. Chi,et al.  Complex deformities of the cervical spine. , 2007, Neurosurgery clinics of North America.

[18]  P. Mummaneni,et al.  Cervicothoracic kyphosis. , 2006, Neurosurgery clinics of North America.

[19]  Shunichi Kawano,et al.  Mechanism of the spinal cord injury and the cervical spondylotic myelopathy: new approach based on the mechanical features of the spinal cord white and gray matter. , 2003, Journal of neurosurgery.