Twenty-year Longitudinal Follow-up MRI Study of Asymptomatic Volunteers: The Impact of Cervical Alignment on Disk Degeneration

Quantitatively assessing the effect of cervical sagittal alignment on dynamic intervertebral kinematics by video-fluoroscopy technique

BACKGROUND

Cervical sagittal alignment is crucial for distributing the head load to lower cervical segments and maintaining normal cervical spine function, but its biomechanical effect on the cervical spine was not fully elucidated.

OBJECTIVE

To investigate the effect of cervical sagittal alignment on dynamic intervertebral kinematics.

DESIGN

Cross-sectional study.

METHODS

Healthy participants without neck pain were recruited and divided into lordosis, straight and kyphosis groups according to the C2-C7 Cobb angle at the neutral position. The anti-directional and total joint motions were extracted across 10 epochs of dynamic cervical flexion and extension movements.

RESULTS

/findings: The overall anti-directional joint motion during flexion is larger in the kyphosis group when compared with the lordosis group (p = 0.021), while the range of flexion is smaller in the kyphosis group than that in the lordosis group (p = 0.017). The C2/C3 anti-directional joint motion during extension in the straight group is larger than that in the lordosis group (p = 0016). The range of extension in the kyphosis group (p < 0.001) and the straight group (p = 0.002) are larger than that in the lordosis group. The increased range of extension in the kyphosis and straight groups were mainly from the C3/C4, C4/C5, and C5/C6 joints(p < 0.05).

CONCLUSION

Changes in cervical sagittal alignment alter both the quality and quantity of the individual joint motions. More adjustments are required by the cervical joints to complete neck movements with the loss of lordosis. The lordotic curvature is a relatively effort-saving mode for the cervical spine from a biomechanical perspective.

A Proposed Personalized Spine Care Protocol (SpineScreen) to Treat Visualized Pain Generators: An Illustrative Study Comparing Clinical Outcomes and Postoperative Reoperations between Targeted Endoscopic Lumbar Decompression Surgery, Minimally Invasive TLIF and Open Laminectomy

Background: Endoscopically visualized spine surgery has become an essential tool that aids in identifying and treating anatomical spine pathologies that are not well demonstrated by traditional advanced imaging, including MRI. These pathologies may be visualized during endoscopic lumbar decompression (ELD) and categorized into primary pain generators (PPG). Identifying these PPGs provides crucial information for a successful outcome with ELD and forms the basis for our proposed personalized spine care protocol (SpineScreen). Methods: a prospective study of 412 patients from 7 endoscopic practices consisting of 207 (50.2%) males and 205 (49.8%) females with an average age of 63.67 years and an average follow-up of 69.27 months was performed to compare the durability of targeted ELD based on validated primary pain generators versus image-based open lumbar laminectomy, and minimally invasive lumbar transforaminal interbody fusion (TLIF) using Kaplan-Meier median survival calculations. The serial time was determined as the interval between index surgery and when patients were censored for additional interventional and surgical treatments for low back-related symptoms. A control group was recruited from patients referred for a surgical consultation but declined interventional and surgical treatment and continued on medical care. Control group patients were censored when they crossed over into any surgical or interventional treatment group. Results: of the 412 study patients, 206 underwent ELD (50.0%), 61 laminectomy (14.8%), and 78 (18.9%) TLIF. There were 67 patients in the control group (16.3% of 412 patients). The most common surgical levels were L4/5 (41.3%), L5/S1 (25.0%), and L4-S1 (16.3%). At two-year f/u, excellent and good Macnab outcomes were reported by 346 of the 412 study patients (84.0%). The VAS leg pain score reduction was 4.250 ± 1.691 (p < 0.001). No other treatment during the available follow-up was required in 60.7% (125/206) of the ELD, 39.9% (31/78) of the TLIF, and 19.7% (12/61 of the laminectomy patients. In control patients, only 15 of the 67 (22.4%) control patients continued with conservative care until final follow-up, all of which had fair and poor functional Macnab outcomes. In patients with Excellent Macnab outcomes, the median durability was 62 months in ELD, 43 in TLIF, and 31 months in laminectomy patients (p < 0.001). The overall survival time in control patients was eight months with a standard error of 0.942, a lower boundary of 6.154, and an upper boundary of 9.846 months. In patients with excellent Macnab outcomes, the median durability was 62 months in ELD, 43 in TLIF, and 31 months in laminectomy patients versus control patients at seven months (p < 0.001). The most common new-onset symptom for censoring was dysesthesia ELD (9.4%; 20/206), axial back pain in TLIF (25.6%;20/78), and recurrent pain in laminectomy (65.6%; 40/61) patients (p < 0.001). Transforaminal epidural steroid injections were tried in 11.7% (24/206) of ELD, 23.1% (18/78) of TLIF, and 36.1% (22/61) of the laminectomy patients. The secondary fusion rate among ELD patients was 8.8% (18/206). Among TLIF patients, the most common additional treatments were revision fusion (19.2%; 15/78) and multilevel rhizotomy (10.3%; 8/78). Common follow-up procedures in laminectomy patients included revision laminectomy (16.4%; 10/61), revision ELD (11.5%; 7/61), and multilevel rhizotomy (11.5%; 7/61). Control patients crossed over into ELD (13.4%), TLIF (13.4%), laminectomy (10.4%) and interventional treatment (40.3%) arms at high rates. Most control patients treated with spinal injections (55.5%) had excellent and good functional outcomes versus 40.7% with fair and poor (3.7%), respectively. The control patients (93.3%) who remained in medical management without surgery or interventional care (14/67) had the worst functional outcomes and were rated as fair and poor. Conclusions: clinical outcomes were more favorable with lumbar surgeries than with non-surgical control groups. Of the control patients, the crossover rate into interventional and surgical care was 40.3% and 37.2%, respectively. There are longer symptom-free intervals after targeted ELD than with TLIF or laminectomy. Additional intervention and surgical treatments are more often needed to manage new-onset postoperative symptoms in TLIF- and laminectomy compared to ELD patients. Few ELD patients will require fusion in the future. Considering the rising cost of surgical spine care, we offer SpineScreen as a simplified and less costly alternative to traditional image-based care models by focusing on primary pain generators rather than image-based criteria derived from the preoperative lumbar MRI scan.

Cervical disc degeneration is associated with a reduction in mobility: A cross-sectional study of 1211 asymptomatic healthy subjects

The aim of this study was to establish the age-related changes and gender-specific differences of cervical disc degeneration using magnetic resonance image (MRI) and to evaluate the correlation between the severity of cervical disc degeneration and mobility in asymptomatic subjects. A total of 1,211 relatively healthy volunteers (606 males and 605 females, mean age 49.5 years) without neurological symptoms underwent MRI. At least 100 males and 100 females in each decade of life between the 20 s and the 70 s were included. This study was part of a larger project and used some previously published data. Cervical disc degeneration was defined according to the modified Pfirrmann classification system. A total disc degeneration score (DDS) was calculated by the summation of individual Pfirrmann scores from C2/C3 to C7/T1. Cervical range of motion (ROM) was measured by radiograph. The total DDS increased gradually with increasing age in both genders. DDSs were lower in females than in males in all decades. A DDS of 13 or more was found in more than half the cases in the 40 s or older age groups. The total DDS was 13 or more in over 95% of the cases in the 70 s age group. The total DDS was significantly and negatively correlated with cervical ROM overall (r =  - 0.46, p < 0.0001) and in both men (r =  - 0.52, p < 0.0001) and women (r =  - 0.40, p < 0.0001). This large-scale cross-sectional analysis of cervical spine MRI data in healthy subjects demonstrated that cervical disc degeneration progresses with age, and is correlated with a reduction in mobility.

The Prevalence of Degenerative Cervical Myelopathy-Related Pathologies on Magnetic Resonance Imaging in Healthy/Asymptomatic Individuals: A Meta-Analysis of Published Studies and Comparison to a Symptomatic Cohort

Degenerative cervical myelopathy (DCM) is a progressive cervical spinal cord injury brought about by mechanical stress from degenerative changes in the cervical spine. It is typically diagnosed on clinical symptoms and examination findings together with MRI findings. In this study, we explore the significance of these degenerative pathology to onset of DCM by performing the first meta-analysis on the prevalence of degenerative features reported on MRI amongst healthy and asymptomatic populations and compare this to the prevalence of degenerative features reported on MRI amongst a symptomatic population calculated in a previous review. We conducted a systematic review and meta-analysis in accordance with PRISMA guidelines, cognizant of their adaptation for epidemiological studies. A search strategy was used to identify original research carrying out MRI screening of cervical spines of asymptomatic patients in MEDLINE and Embase from 1985 to present day. The search yielded a total of 1098 studies of which 17 were included in this meta-analysis covering a total of 5059 patients. Ossification of posterior longitudinal ligament (pooled asymptomatic prevalence of 0.4%, 95% Confidence Interval [0.1%, 0.8%]), enlargement of ligamentum flavum (pooled asymptomatic prevalence of 11.8%, 95% Confidence Interval [5.3%, 18.4%]) and degenerative multilevel disc pathology (pooled asymptomatic prevalence of 64.5%, 95% Confidence Interval [48.3%, 80.8%], I² 100%) were found to be significantly lower in asymptomatic populations. Symptomatic populations have a prevalence of 10.5% (95% Confidence Interval [7.7%, 13.3%]) for ossification of posterior longitudinal ligament, 56.8% (95% Confidence Interval [52.3%, 61.3%]) for enlargement of ligamentum flavum and 89.7% (95% Confidence Interval [86.9%, 92.5%]) for degenerative multilevel disc pathology [18]. Understanding the natural history of DCM is a recognised research priority, and whilst these perspectives require further evaluation, they may be of significant relevance to the evolving biomechanical understanding of the disease.

Normative Magnetic Resonance Imaging Data of Age-Related Degenerative Changes in Cervical Disc Morphology

OBJECTIVE

Few studies have examined a possible correlation between cervical disc degeneration and disc height. The aim of this study was to establish age-related changes and sex-specific differences of cervical disc height using magnetic resonance imaging (MRI) and to evaluate the relationship between degree of cervical disc degeneration and disc height in asymptomatic subjects.

METHODS

We measured the intervertebral disc anteroposterior diameter and disc height in each disc level using MRI in 1211 relatively healthy volunteers (606 men and 605 women, mean age 49.5 years). We included at least 100 males and 100 females in each decade of life between the 20s and the 70s. Cervical disc degeneration was defined according to the modified Pfirrmann classification system, and disc index and intervertebral disc height narrowing ratio were evaluated on sagittal plane MRI.

RESULTS

Intervertebral disc height decreased gradually with increasing age in both sexes. The grade of disc degeneration significantly increased with age in both sexes at every level. Mild disc degeneration was observed even in subjects their 20s. Disc degeneration occurred around the C5-C6 level. The average disc height decreased with aging after the 40s. Disc index and intervertebral disc height narrowing ratio decreased with a progression in the disc degeneration grade in both sexes.

CONCLUSIONS

This large-scale cross-sectional analysis of cervical spine MRI data in healthy subjects demonstrated that cervical disc height narrowing progresses with age. Cervical disc height narrowing is highly correlated with the progression of disc degeneration.

Prevalence of cervical spine degenerative changes in elderly population and its weak association with aging, neck pain, and osteoporosis

Background

To investigate the prevalence of MRI degenerative findings of cervical spine in elderly Chinese males and females.

Methods

From a general population sample, cervical spine T2 weighted sagittal MR images were acquired in 272 males (mean age: 82.9±3.83) and 150 females (mean age: 81.5±4.27). Images were interpreted and degenerative changes were classified. Study subjects were divided into younger group (group A, ≤81 years) and older group (group B, >81 years). For neck pain, question was structured as 'during the past 12 months, have you had any neck pain?'. Two hundred and fifty-two males and 134 females also had hip bone mineral density (BMD) measured.

Results

98.1% subjects exhibited at least one degenerative change at one or more vertebral levels. The C5/6 level had the highest overall frequency for degenerative changes. Most of the degenerative changes were more common in females. The older female group had higher prevalence or higher severity of degenerative findings than the younger group. Eleven point four percent of the males and 20.6% of the females reported neck pain, and male subjects with neck pain tended to have slightly higher prevalence of cervical degenerative changes. There was a weak trend that osteoporosis was associated with a higher prevalence of spinal cord high signal and a higher prevalence of spinal canal stenosis.

Conclusions

The age-dependence of cervical spine degenerative changes was more notable in females. Subjects with neck pain and subjects with osteoporosis were weakly associated with higher prevalence of cervical degenerative changes.