Impact of the surgical treatment for degenerative cervical myelopathy on the preoperative cervical sagittal balance: a review of prospective comparative cohort between anterior decompression with fusion and laminoplasty
- 896 Downloads
Cervical sagittal balance has received increased attention as an important determinant of radiological and clinical outcomes. However, no prospective studies have compared the impact of cervical sagittal balance between anterior and posterior surgeries. We previously conducted a prospective study comparing anterior decompression with fusion (ADF) and laminoplasty (LAMP) for degenerative cervical myelopathy (DCM) and reported; however, analysis of cervical alignment within the concept of sagittal balance has yet to be performed, because that concept has recently been proposed. This study aimed to review this prospective cohort, specifically focusing on cervical sagittal balance.
We prospectively performed ADF or LAMP for DCM patients based on the year of enrollment: ADF was performed in odd-numbered years and LAMP in even-numbered years. Cervical lateral X-ray images taken in the neutral standing position were evaluated preoperatively and at a 1-year follow-up. The radiographic measurements included the following: (1) CL (cervical lordosis: C2–7 lordotic angle), (2) CGH (center of gravity of the head)-C7 SVA (sagittal vertical axis), and (3) C7 slope. The clinical results were evaluated using the Japanese Orthopedic Association scoring system for cervical myelopathy (C-JOA score).
We analyzed the data for 66 patients (ADF n = 28, LAMP n = 38). While the CL and CGH-C7 SVA in the ADF were unchanged after the operation, those in the LAMP group worsened, especially in patients with preoperative cervical sagittal imbalance. The C7 slopes were not affected by the operation in either group. The postoperative decreases in the CL in the LAMP group correlated with the preoperative CGH-C7 SVA (r = 0.618, P < 0.01), but those in ADF group did not. In patients with preoperative cervical sagittal imbalance (CGH-C7 SVA ≥40 mm), the recovery rate of the C-JOA score in the ADF group was superior to that in the LAMP group (67.3 vs. 39.8 %). In contrast, for patients without cervical sagittal imbalance, the recovery rate of the C-JOA score showed no significant difference between the ADF and LAMP groups (64.5 vs. 58.7 %).
Postoperative cervical sagittal alignment and balance were maintained after ADF but deteriorated following LAMP, especially in patients with preoperative CGH-C7 SVA ≥40 mm. In these patients, neurological recovery after LAMP was unsatisfactory. LAMP is not suitable for degenerative cervical myelopathy patients with preoperative cervical sagittal imbalance.
KeywordsCervical sagittal balance Cervical spondylotic myelopathy Degenerative cervical myelopathy Anterior decompression with fusion Laminoplasty
We gratefully acknowledge Dr. Satoru Egawa to help our work. This work was supported by Japanese Health Labour Sciences Research Grant.
Compliance with ethical standards
Conflict of interest
- 4.Diebo BG, Challier V, Henry JK et al (2016) Predicting cervical alignment required to maintain horizontal gaze based on global spinal alignment. Spine (Phila Pa 1976) [Epub ahead of print]Google Scholar
- 5.Fehling MG, Ibrahim A, Tetreault L et al (2015) A global perspective on the outcomes of surgical decompression in patients with cervical spondylotic myelopathy: result from the prospective multicenter AOSpine international study on 479 patients. Spine (Phila Pa 1976) 40(17):1322–1328. doi: 10.1097/BRS.0000000000000988 CrossRefGoogle Scholar
- 7.Hirai T, Okawa A, Arai Y et al (2011) Middle-term results of a prospective comparative study of anterior decompression with fusion and posterior decompression with laminoplasty for the treatment of cervical spondylotic myelopathy. Spine (Phila Pa 1976) 36(23):1940–1947. doi: 10.1097/BRS.0b013e3181feeeb2 CrossRefGoogle Scholar
- 8.Jalai CM, Passias PG, Lafage V et al (2016) A comparative analysis of the prevalence and characteristics of cervical malalignment in adults presenting with thoracolumbar spine deformity based on variations in treatment approach over 2 years. Eur Spine J [Epub ahead of print]Google Scholar
- 13.Lee CH, Jahng TA, Hyun SJ, Kim KJ, Kim HJ (2016) Expansive laminoplasty versus laminectomy alone versus laminectomy and fusion for cervical ossification of the posterior longitudinal ligament: is there a difference in the clinical outcome and sagittal alignment? Clin Spine Surg 29(19):E9–E15. doi: 10.1097/BSD.0000000000000058 PubMedGoogle Scholar
- 18.Miyamoto H, Maeno K, Uno K et al (2014) Outcomes of surgical intervention for cervical spondylotic myelopathy accompanying local kyphosis (comparison between laminoplasty alone and posterior reconstruction surgery using the screw-rod system). Eur Spine J 23(2):341–346. doi: 10.1007/s00586-013-2923-1 CrossRefPubMedGoogle Scholar
- 20.Oshima Y, Takeshita K, Taniguchi Y et al (2016) Effect of preoperative sagittal balance on cervical laminoplasty outcomes. Spine (Phila Pa 1976) [Epub ahead of print]Google Scholar
- 22.Protopsaltis TS, Scheer JK, Terran JS et al (2015) How the neck affects the back: changes in regional cervical sagittal alignment correlate to HRQOL improvement in adult thoracolumbar deformity patients at 2-year follow-up. J Nuerosurg Spine 23(2):153–158. doi: 10.3171/2014.11.SPINE1441 CrossRefPubMedGoogle Scholar
- 24.Ratliff JK, Cooper PR (2003) Cervical laminoplasty: a critical review. J Neurosug 98(3 Suppl):230–238Google Scholar
- 26.Sakai K, Okawa A, Takahashi M et al (2012) Five-year follow-up of surgical treatment caused by ossification of the posterior longitudinal ligament: a prospective comparative study of anterior decompression and fusion with floating method versus laminoplasty. Spine (Phila Pa 1976) 37(5):367–376. doi: 10.1097/BRS.0b013e31821f4a51 CrossRefGoogle Scholar
- 27.Sakai K, Yoshii T, Hirai T et al (2016) Cervical sagittal imbalance is a predictor of kyphotic deformity after laminoplasty in cervical spondylotic myelopathy patients without preoperative kyphotic alignment. Spine (Phila Pa 1976) 41(4):299–305. doi: 10.1097/BRS.0000000000001206 CrossRefGoogle Scholar
- 28.Shamji MF, Mohanty C, Massicotte EM, Fehlings MG (2016) The association of cervical spine alignment with neurologic recovery in a prospective cohort of patients with surgical myelopathy: analysis of a series of 124 cases. World Neurosurg 86:112–119. doi: 10.1016/j.wneu.2015.09.044 CrossRefPubMedGoogle Scholar
- 32.Suda K, Abumi K, Ito M et al (2003) Local kyphosis reduces surgical outcomes of expansive open-door laminoplasty for cervical spondylotic myelopathy. Spine (Phila Pa 1976) 28(12):1258–1262Google Scholar
- 35.Traynelis VC, Arnold PM, Fourney DR et al (2013) Alternative procedures for the treatment of cervical spondylotic myelopathy: arthroplasty, oblique corpectomy, skip laminectomy: evaluation of comparative effectiveness and safety. Spine (Phila Pa 1976) 38(22 Suppl 1):S210–S231. doi: 10.1097/BRS.0000000000000009 CrossRefGoogle Scholar