Cervical sagittal alignment after Prestige LP cervical disc replacement: radiological results and clinical impacts from a single-center experience

Abstract

Background Cervical disc replacement (CDR) has been widely used to treat one- and two-level cervical degenerative disc disease. Studies have shown the effectiveness of CDR in preserving range of motion (ROM) and delaying adjacent segment degeneration (ASD). Cervical sagittal alignment is an important factor affecting favorable clinical outcomes in cervical spine surgery. This study aimed to explore whether cervical sagittal alignment can be maintained after CDR and to identify the impact of cervical sagittal alignment on outcomes after CDR. Methods This was a single-center, retrospective study. 132 patients who underwent one-level CDR were included. Cervical sagittal alignments, including cervical lordosis (CL), segmental alignment (SA), sagittal vertical axis (SVA), T1 slope (T1s), and T1s minus CL (T1s-CL), were measured. The effects of cervical sagittal alignment on the CDR outcomes were analyzed. Patients were divided into the heterotopic ossification (HO) group and ASD group to determine the potential impacts of cervical sagittal parameters. Results The cervical sagittal alignment parameters, except for the SVA, were significantly improved after CDR and showed decreasing trends at the last follow-up. Significantly higher CL and T1s were found in patients with better ROM after CDR. SVA ≥ 20 mm increased the risk of anterior HO (odds ratio = 2.945, P = 0.007). Significantly kyphotic SA and lower T1s values were found in the ASD patients than in the non-ASD patients (P < 0.05). Patients with ASD at the inferior level showed significantly worse CL (P < 0.05). Conclusion CDR had limited function of improving cervical sagittal alignment. Poor cervical sagittal alignment after CDR was associated with HO, ASD, and less ROM.

Fatty infiltration in cervical extensor muscle: is there a relationship with cervical sagittal alignment after anterior cervical discectomy and fusion?

“…Static and dynamic lateral X-ray images were used to measure the cervical sagittal alignment and the parameters included C2-C7 Cobb angle, functional spinal unit (FSU) angle, range of motion (ROM) of C2-C7, the sagittal vertical axis (SVA) and T1 slope(T1S) [ 24 ]. The C2-C7 Cobb angle was formed between the lower endplate of the C2 vertebral body and the lower endplate of the C7 vertebral body.…”

Is there a difference in the outcomes of anterior cervical discectomy and fusion among female patients with different menopausal statuses?

“…Nevertheless, CL loss and the FSU angle tend to shift the axial load from the posterior column to the anterior column. The change in cervical alignment potentially increases the mechanical stress in the anterior column and adjacent levels, which will also interfere with the biomechanical environment [ 36 ]. Moreover, the BMD and HU values were both inferior in the late postmenopausal group, which may partly lead to changes in cervical alignment and graft subsidence after ACDF [ 26 , 37 ].…”

Personalised gravitational loading of the cervical spine from biplanar X-rays for asymptomatic and clinical subjects in neutral standing position

“…However, these observations are limited by the absence of evaluation of the evolution of pain for the patients, as well as by the very short postoperative follow-up. Studies with much longer postoperative followups have demonstrated changes in cervical alignment in both arthrodesis (Hyun et al, 2017;Lan et al, 2019) and arthroplasty (Guérin et al, 2012;Kim et al, 2008;Wang et al, 2021). Some of these changes have been identified as risk factors for complications such as ASD (Katsuura et al, 2001;Xiong et al, 2020) and pseudarthrosis (Choi et al, 2017).…”