Laminoplasty Achieves Improved Outcomes Despite Leading to a More Positive Sagittal Balance: Neither Preoperative Nor Postoperative Sagittal Balance Correlated With Spine-specific Outcome Data. Issue 1 (February 2022)

• Record Type: Journal Article
• Authors: Niu, Shuo; Anastasio, Albert T.; Rhee, John M.
• Is Part Of: Clinical spine surgery. Volume 35:Issue 1(2022)
• Publication Date: 2022-02
• Subjects: cervical sagittal balance -- cervical sagittal alignment -- myelopathy -- laminoplasty -- surgical outcome -- patient-reported outcome; Spinal cord -- Diseases -- Periodicals; Spinal cord -- Surgery -- Periodicals; 617.56059
• DOI: 10.1097/BSD.0000000000001165
• Languages: English
• ISSNs: 2380-0186

Abstract

Abstract : Study Design: A retrospective study of prospective data. Objective: Determine the correlation between cervical sagittal alignment, either preoperative or postoperative, and the outcomes of laminoplasty. Summary of Background Data: Cervical laminoplasty is a common surgical treatment for myelopathy. However, the effect of preoperative or postoperative cervical sagittal alignment on outcomes, such as neurological improvement and patient-reported outcomes, remains unclear. Methods: A total of 144 consecutive patients (2007–2017) with laminoplasty for myelopathy and a minimum of 1-year postoperative follow-up were reviewed. The severity of myelopathy was assessed by modified Japanese Orthopedic Association (mJOA) scores. Total pain was measured by the visual analog scale. Patient-reported outcome included neck disability index (NDI) and 12-item short-form survey (SF-12). Radiographic measures of cervical sagittal alignment on x-ray images consisted of C2–C7 angle, T1 slope, C2–C7 sagittal vertical axis (SVA), and C2–C7 forward pitch (FP). Patients were also divided into 2 groups based on the postoperative C2–C7 SVA (≥40 or <40 mm) for outcome comparison. Results: Laminoplasty yielded improvement in functionality as evidenced by significantly increased mJOA scores, decreased total pain scores, and improved NDI scores at final follow-up. There was a change in sagittal balance postoperatively with significantly increased C2–C7 SVA and FP (7–8 mm increase). However, there was no correlation between preoperative sagittal alignment and outcomes. There was also no correlation between postoperative sagittal alignment and most outcomes, except for a significantly negative correlation between FP and short form-physical component summary (Spearman r =−0.328, P =0.011). When those with postoperative C2–C7 SVA ≥40 mm (n=60) were compared with those with <40 mm (n=84), there was no significant difference in outcomes. Conclusions: Cervical laminoplasty yields significant neurological and functional improvement despite a more positive sagittal balance postoperatively, with increased C2–C7 SVA and FP. However, other than a lower short form-physical component summary score, neither preoperative nor postoperative sagittal alignment measures correlated with spine-specific outcomes. Level of Evidence: Level II—a retrospective cohort study.