Lumbar spinal stenosis has a negative impact on quality of life compared with other comorbidities: an epidemiological cross-sectional study of 1862 community-dwelling individuals.

Lumbar spinal stenosis (LSS) is common in the elderly. However, there have been few reports on its impact on quality of life (QoL) in community-dwelling individuals. The purpose of this study was to clarify how symptomatic LSS affects QoL at the community level. A total of 1862 people (697 males and 1165 females, most subjects were between 40 and 85 y.o.) agreed to participate and were interviewed. The presence of symptomatic LSS was assessed by a specially designed questionnaire. The Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) was also administered. In addition, the presence of comorbid conditions that affect QoL, such as osteoarthritis of the knee and hip, cardiovascular disease, cerebrovascular disease, or respiratory disease, was also analyzed. The prevalence of symptomatic LSS gradually increased with age. Furthermore, the presence of symptomatic LSS had a strong negative effect on all 8 physical and mental domains and the physical component summary (PCS) (OR: 1.547-2.544) but not the mental component summary (MCS). In comparison with comorbid conditions, LSS had a much stronger negative impact on health-related QoL (HR-QoL). The current study confirmed that the presence of symptomatic LSS might have a strong negative influence on HR-QoL in the community setting.

Effect of acute nerve root compression on endoneurial fluid pressure and blood flow in rat dorsal root ganglia.

The objective of the current study was to test the hypothesis that crush injury to nerve root increases endoneurial fluid pressure (EFP) and decreases blood flow in the associated dorsal root ganglion (DRG). A total of 21 adult, female Sprague-Dawley rats had their left L5 nerve root and DRG exposed. The L5 nerve root was clamped for 2 s with a vascular suture clip just proximal to the DRG (compression group). Sham-operated animals without compression were used for control (control group). EFP was recorded with a servo-null micropipette system using a glass micropipette with tip diameter of 4 mum before and after 3 h of treatment. After the final measurement of EFP, DRG was excised and processed for histology. Blood flow in the DRG was continuously monitored by laser Doppler flow meter for 3 h. Three hours after treatment, EFP was 4.7+/-2.7 cm H(2)O in the compression group and 2.2+/-1.2 cm H(2)O in the control group (P<0.05). Edema was the principal pathologic findings seen consistently in the DRG from animals in the compression group. Blood flow in the compression group was reduced 10 min after compression. This reduction was statistically significant compared with that of the control (P<0.01). An acute compression to the nerve root increased endoneurial edema, increased EFP in the associated DRG, and reduced DRG blood flow. This combination of increased EFP and decreased blood flow in the DRG may result in neuronal ischemia and sensory dysfunction. These acute pathophysiologic changes may thus have a role in the pathogenesis of low back pain and sciatica due to disc herniation and spinal canal stenosis.

Anatomic study of the axis for surgical planning of transarticular screw fixation.

Transarticular screw fixation has shown increased stability compared with other posterior stabilization techniques. However, there have been few reports on vertebral artery injury related to the screw insertion. The current study measured the parameters of the pedicle and vertebral artery groove of the axis and clarified the accuracy and safety of the transarticular screw fixation. Direct measurements were taken from 98 dry axis vertebrae. The width and height of the pedicle were measured. The mediolateral and anteroposterior dimensions of the vertebral artery groove also were measured. Forty-one percent had asymmetry. In 20% of the specimens, the pedicle was smaller than the diameter of the screw (3.5 mm). The pedicle of the axis has large anatomic variability and asymmetry. Some pedicles were not suitable for atlantoaxial transarticular screw fixation. The risks associated with screw fixation should be prevented by preoperative computed tomography with three-dimensional reconstruction. Screw trajectory reconstruction with coronal and sagittal reconstruction is useful to evaluate the pedicle width and height.