The possible impact of cervical stenosis on cephalad neuronal dysfunction

Comparative clinical and morphometric investigations of cervical stenosis of the spinal canal in humans and dogs

Acquired stenosis of the spinal canal is a common problem in human and animal pathology. It is defined as a pathological condition that mainly develops as degeneration of the spine with cervical myelopathy development, which is a characteristic manifestation of this pathology. Pain both in the neck and upper back is the leading syndrome of this pathology. 65 human patients aged 20–65 years and 19 dogs weighing more than 20 kg were examined with the aim of comparative clinical and morphometric analysis of stenosis of the spinal canal. The age of the dogs was maximally converted to the age of a person. Computed tomography using the Pavlov-Torg index and the reserve space evaluation supplemented diagnosis of stenosis of the spinal canal. The mass proportion of stenotic changes of the spinal canal against the background of the degenerative-dystrophic process was 21 in males (n = 25) 84.0%, females – 28 persons (n = 40) 70.0%. Pain syndrome was the main complaint in all patients. Cervicalgia prevailed in 60 (92.3%), pain in the upper back was registered in 32 (49.2%) patients. The intensity of pain syndrome was equal to 3.1 ± 0.4 points. Motor deficiency in the form of paresis, mainly of the distal parts of the hands, was registered in 48 patients (73.8%), pyramidal symptoms were noted in the legs in 32 (49.2%) patients, pelvic reservoir dysfunction (7.0–10.8%), and sensory disorders were also found (24.0–36.9%). Such manifestations of cervical myelopathy progressed slowly. Pyramidal symptoms were more frequent and more pronounced in men. According to the computed tomography scan, degenerative changes of the spine were maximal at the level of the C6 vertebra with the maximum clinical correlation (neurological deficit, pain syndrome, etc.). In the course of the research, probable stenosis of the spinal canal was found in people on computed tomography images. In the 19 dogs observed weighing 20 kg or more the presence of pain syndrome was evaluated in all the animals (100.0%) as well as behaviour change (100.0%). During the examination, gait disorder was detected (18.0–94.7%); reaction to palpation of the neck area (15.0–78.9%); the habitus of animals experiencing pain, especially during neck movements (14.0–73.7%), body tension (12.0–63.1%), etc. Bony outgrowths of the edges of the vertebrae and intervertebral joints were found in almost all dogs of 18 (94.7%) large breeds compared to others. Narrowing of the intervertebral openings, deformation and sclerotic changes of the locking plates, thickening of the yellow and elongated ligaments occurred three to four times more in large breeds compared to dogs weighing less than 20 kg, and were absent in cats. Stenosis of the spinal canal was detected in 15 (78.9%) dogs. Therefore, acquired stenosis of the spinal canal probably develops after degenerative-dystrophic changes in the neck in 87.7% of people and in 78.9% of dogs with clinical manifestations of cervical myelopathy and with persistent pain syndrome (equal to 3.1 ± 0.3 points in humans and 2.6 ± 0.4 points in animals according to visual analog scale). This kind of pathological process in the investigated groups developed mainly at the level of the C6 vertebra. Similar clinical and morphometric indexes were obtained in humans (87.7%). It was found that the maximum similarity of pathological processes with stenosis of the spinal canal formation was characteristic in dogs of exclusively large breeds. Therefore, we consider it promising to study the development mechanisms of stenosis of the spinal canal and peculiarities primarily in young generations of humans and animals, to implement modern non-invasive neuroimaging methods, in particular for animals with investigation of morphometric indexes. This will prevent the occurrence of most comorbid syndromes, including chronic pain, neurological deficits as well as help find new opportunities for correction of stenosis of the spinal canal, to suppress the aging processes not only of the muscle-skeletal system but also of the body as a whole. The importance of this work, we suppose, lies in the further identification of adequate models in animals of different breeds and weight categories with stenosis of the spinal canal pathology in which it develops significantly faster, for extrapolation to humans to predict the development of pathological events.

Association of Lumbar Spinal Stenosis with Severe Disability and Mortality Among Community-Dwelling Older Adults: The Locomotive Syndrome and Health Outcomes in the Aizu Cohort Study

STUDY DESIGN

This prospective cohort study analyzed data from the Locomotive Syndrome and Health Outcomes in the Aizu Cohort Study.

OBJECTIVE

To investigate the association between lumbar spinal stenosis (LSS) and severe disability and mortality among community-dwelling older adults.

SUMMARY OF BACKGROUND DATA

Only a few studies have investigated LSS longitudinally, and the study participants were limited to selected patients diagnosed with LSS during a hospital visit. Additionally, the prognosis of LSS remains unclear.

METHODS

We enrolled independent community-dwelling older adults aged 65 years or older at the time of a baseline health checkup in 2008. LSS was diagnosed using a validated diagnostic support tool for LSS. The primary endpoint was a composite of severe disability (long-term care insurance certification grade 4 or 5) and mortality. We used 1 minus Kaplan-Meier failure estimates and the log-rank test to compare the interval between baseline and the predetermined endpoint as well as a Cox proportional hazards model to estimate hazard ratios (HRs) for the LSS group with adjustment for possible confounders. Multiple imputation by chained equations was performed for sensitivity analysis.

RESULTS

Of 2058 subjects enrolled, 1560 did not have missing covariates; 269 (17%) were diagnosed with LSS. After a median follow-up of 5.8 years, the rates of severe disability and mortality were 0.022 per year in subjects with LSS and 0.012 per year in those without (P = 0.006). The adjusted HR for the composite endpoint in the LSS group was 1.55 (95% confidence interval [CI], 1.01-2.38). A similar association was observed after multiple imputation of missing covariates (adjusted HR, 1.51 [95% CI, 1.06-2.16]).

CONCLUSION

LSS was associated with severe disability and mortality in community-dwelling older adults. Detection of adults with LSS in the community may contribute to local health promotion.Level of Evidence: 2.

Elevated Mitochondrial Reactive Oxygen Species within Cerebrospinal Fluid as New Index in the Early Detection of Lumbar Spinal Stenosis

Lumbar spinal stenosis (LSS) is a common neurodegenerative condition. However, how neurogenic claudication develops with severe leg pain has not yet been clearly elucidated. Moreover, cerebrospinal fluid (CSF) physiology at the lumbosacral level is poorly understood because of the difficulties involved in quantification and visualization. Recent studies have suggested that assessment of mitochondrial function in CSF provides an indirect way to assess neurological disorders and an important feature of disease progression. In this study, we assessed the relevance of endogenous extracellular mitochondria in the CSF of rats after LSS. Mitochondrial changes within the CSF were analyzed following LSS at 1 week using flow cytometry. An increase in cell size and number was observed in CSF with LSS, and reactive oxygen species (ROS) levels were also increased within the CSF at 1 week in the LSS group. Elevated mitochondrial ROS and functional changes in the CSF are hallmarks of LSS. The present study is the first to demonstrate that elevated mitochondrial ROS within the CSF is a new index for the early detection of LSS. Moreover, it may represent a potential novel treatment target for LSS.