Cervical Subcutaneous Fat Thickness and Its Association with Sagittal Parameters and Clinical Outcomes Following Laminoplasty in Patients with Cervical Spondylotic Myelopathy.

Abstract

To investigate the association between cervical subcutaneous fat thickness, sagittal alignment parameters, and clinical outcomes following laminoplasty in patients with cervical spondylotic myelopathy (CSM). A total of 131 patients with CSM who underwent single-door cervical laminoplasty between January 2021 and June 2023 were retrospectively analyzed, with an average follow-up period of 14.02 ±1.45 months. Subcutaneous fat thickness at the C5 vertebral level and skin-to-lamina distance were measured. Demographic characteristics, cervical sagittal parameters, surgical details, and postoperative outcomes were collected. Interobserver reliability was assessed using intraclass correlation coefficient. Binary logistic regression and receiver operating characteristic curve analyses were conducted to identify predictors of postoperative axial symptoms. Patients with greater subcutaneous fat thickness exhibited higher body mass index, greater body weight, shorter cervical length, smaller C2-C7 Cobb angles, higher T1 slope, and more severe paraspinal muscle fatty infiltration (all P < 0.05). The average of follow-up time is 14.02 ±1.445 months. There are no differences in final Japanese Orthopaedic Association and visual analog scale follow-up. But thicker subcutaneous fat patients have a higher incidence of postoperative axial symptoms (P = 0.02). Subcutaneous fat thickness was identified as the strongest independent predictor of axial symptoms (B = 0.828, P = 0.002), with receiver operating characteristic analysis showing moderate predictive ability (area under the curve = 0.64) and an optimal cutoff value of 1.357 cm. Greater cervical subcutaneous fat thickness is associated with abnormal sagittal alignment and increased risk of postoperative axial symptosms after laminoplasty. Subcutaneous fat thickness may serve as a practical localized predictor to optimize surgical planning and postoperative management in CSM patients.