Lee Dong-Ho, Lee Choon Sung, Hwang Chang Ju, Cho Jae Hwan, Park Jae-Woo, Park Kun-Bo
1Department of Orthopedic Surgery, Asan Medical Center, University of Ulsan College of Medicine; and.
2Division of Orthopedic Surgery, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
J Neurosurg Spine. 2020 May 22;33(3):307-315. doi: 10.3171/2020.3.SPINE2089. Print 2020 Sep 1.
Vertebral body sliding osteotomy (VBSO) is a safe, novel technique for anterior decompression in patients with multilevel cervical spondylotic myelopathy. Another advantage of VBSO may be the restoration of cervical lordosis through multilevel anterior cervical discectomy and fusion (ACDF) above and below the osteotomy level. This study aimed to evaluate the improvement and maintenance of cervical lordosis and sagittal alignment after VBSO.
A total of 65 patients were included; 34 patients had undergone VBSO, and 31 had undergone anterior cervical corpectomy and fusion (ACCF). Preoperative, postoperative, and final follow-up radiographs were used to evaluate the improvements in cervical lordosis and sagittal alignment after VBSO. C0-2 lordosis, C2-7 lordosis, segmental lordosis, C2-7 sagittal vertical axis (SVA), T1 slope, thoracic kyphosis, lumbar lordosis, sacral slope, pelvic tilt, and Japanese Orthopaedic Association scores were measured. Subgroup analysis was performed between 15 patients with 1-level VBSO and 19 patients with 2-level VBSO. Patients with 1-level VBSO were compared to patients who had undergone 1-level ACCF.
C0-2 lordosis (41.3° ± 7.1°), C2-7 lordosis (7.1° ± 12.8°), segmental lordosis (3.1° ± 9.2°), and C2-7 SVA (21.5 ± 11.7 mm) showed significant improvements at the final follow-up (39.3° ± 7.2°, 13° ± 9.9°, 15.2° ± 8.5°, and 18.4 ± 7.9 mm, respectively) after VBSO (p = 0.049, p < 0.001, p < 0.001, and p = 0.038, respectively). The postoperative segmental lordosis was significantly larger in 2-level VBSO (18.8° ± 11.6°) than 1-level VBSO (10.3° ± 5.5°, p = 0.014). The final segmental lordosis was larger in the 1-level VBSO (12.5° ± 6.2°) than the 1-level ACCF (7.2° ± 7.6°, p = 0.023). Segmental lordosis increased postoperatively (p < 0.001) and was maintained until the final follow-up (p = 0.062) after VBSO. However, the postoperatively improved segmental lordosis (p < 0.001) decreased at the final follow-up (p = 0.045) after ACCF.
Not only C2-7 lordosis and segmental lordosis, but also C0-2 lordosis and C2-7 SVA improved at the final follow-up after VBSO. VBSO improves segmental cervical lordosis markedly through multiple ACDFs above and below the VBSO level, and a preserved vertebral body may provide more structural support.
椎体滑动截骨术（VBSO）是一种用于多节段脊髓型颈椎病患者前路减压的安全、新颖的技术。VBSO的另一个优点可能是通过截骨水平上下的多节段颈椎前路椎间盘切除融合术（ACDF）恢复颈椎前凸。本研究旨在评估VBSO术后颈椎前凸和矢状面排列的改善及维持情况。
共纳入65例患者；34例行VBSO，31例行颈椎前路椎体次全切除融合术（ACCF）。术前、术后及末次随访的X线片用于评估VBSO术后颈椎前凸和矢状面排列的改善情况。测量C0-2前凸、C2-7前凸、节段性前凸、C2-7矢状垂直轴（SVA）、T1斜率、胸椎后凸、腰椎前凸、骶骨斜率、骨盆倾斜度及日本骨科协会评分。对15例单节段VBSO患者和19例双节段VBSO患者进行亚组分析。将单节段VBSO患者与接受单节段ACCF的患者进行比较。
VBSO术后末次随访时，C0-2前凸（41.3°±7.1°）、C2-7前凸（7.1°±12.8°）、节段性前凸（3.1°±9.2°）和C2-7 SVA（21.5±11.7mm）均有显著改善（分别为39.3°±7.2°、13°±9.9°、15.2°±8.5°和18.4±7.9mm，p分别为0.049、p<0.001、p<0.001和p=0.038）。双节段VBSO术后节段性前凸（18.8°±11.6°）显著大于单节段VBSO（10.3°±5.5°，p=0.014）。单节段VBSO末次随访时的节段性前凸（12.5°±6.2°）大于单节段ACCF（7.2°±7.6°，p=0.023）。VBSO术后节段性前凸增加（p<0.001）并维持至末次随访（p=0.062）。然而，ACCF术后改善的节段性前凸在末次随访时下降（p<0.001）（p=0.045）。
VBSO术后末次随访时，不仅C2-7前凸和节段性前凸，C0-2前凸和C2-7 SVA也得到改善。VBSO通过VBSO水平上下的多个ACDF显著改善节段性颈椎前凸，保留的椎体可能提供更多的结构支撑。
