ABSTRACT
BACKGROUND AND PURPOSE: Epidural steroid injections may offer little-to-no short-term benefit in the overall population of patients with symptomatic spinal stenosis compared with lidocaine alone. We investigated whether imaging could identify subgroups of patients who might benefit most. MATERIALS AND METHODS: A secondary analysis of the Lumbar Epidural Steroid Injections for Spinal Stenosis prospective, double-blind trial was performed, and patients were randomized to receive an epidural injection of lidocaine with or without corticosteroids. Patients (n = 350) were evaluated for qualitative and quantitative MR imaging or CT measures of lumbar spinal stenosis. The primary clinical end points were the Roland-Morris Disability Questionnaire and the leg pain numeric rating scale at 3 weeks following injection. ANCOVA was used to assess the significance of interaction terms between imaging measures of spinal stenosis and injectate type on clinical improvement. RESULTS: There was no difference in the improvement of disability or leg pain scores at 3 weeks between patients injected with epidural lidocaine alone compared with corticosteroid and lidocaine when accounting for the primary imaging measures of qualitative spinal stenosis assessment (interaction coefficients for disability score, -0.1; 95% CI, -1.3 to 1.2; P = .90; and for the leg pain score, 0.1; 95% CI, -0.6 to 0.8; P = .81) or the quantitative minimum thecal sac cross-sectional area (interaction coefficients for disability score, 0.01; 95% CI, -0.01 to 0.03; P = .40; and for the leg pain score, 0.01; 95% CI, -0.01 to 0.03; P = .33). CONCLUSIONS: Imaging measures of spinal stenosis are not associated with differential clinical responses following epidural corticosteroid injection.
Subject(s)
Adrenal Cortex Hormones/administration & dosage , Lidocaine/administration & dosage , Spinal Stenosis/diagnostic imaging , Spinal Stenosis/drug therapy , Treatment Outcome , Adult , Aged , Anesthetics, Local/administration & dosage , Anti-Inflammatory Agents/administration & dosage , Double-Blind Method , Drug Therapy, Combination/methods , Female , Humans , Injections, Epidural/methods , Lumbar Vertebrae , Magnetic Resonance Imaging/methods , Male , Middle Aged , Randomized Controlled Trials as Topic , Retrospective Studies , Spinal Stenosis/pathology , Tomography, X-Ray Computed/methodsABSTRACT
Performing epidural injections is a complex task that demands a high level of skill and precision from the physician, since an improperly performed procedure can result in serious complications for the patient. The objective of our project is to create an epidural injection simulator for medical training and education that provides the user with realistic feel encountered during an actual procedure. We have used a Phantom haptic interface by SensAble Technologies, which is capable of three-dimensional force feedback, to simulate interactions between the needle and bones or tissues. An additional degree-of-freedom through an actual syringe was incorporated to simulate the "loss of resistance" effect, commonly considered to be the most reliable method for identifying the epidural space during an injection procedure. The simulator also includes a new training feature called "Haptic Guidance" that allows the user to follow a previously recorded expert procedure and feel the encountered forces. Evaluations of the simulator by experienced professionals indicate that the simulation system has considerable potential to become a useful aid in medical training.
Subject(s)
Computer Simulation , Education, Medical , Feedback , Injections, Epidural , User-Computer Interface , Humans , Phantoms, ImagingABSTRACT
OBJECTIVE: To analyze the role of the rectus femoris muscle in nondisabled gait at various walking velocities using fine-wire dynamic electromyography. DESIGN: Descriptive study. Fine-wire electromyography data were collected from the rectus femoris during level walking at four walking speeds. Rectus femoris activity patterns in the loading response phase and the pre- and initial-swing phase of the gait cycle were compared using paired t tests. SETTING: A gait laboratory. SUBJECTS: Ten nondisabled adult volunteers. MAIN OUTCOME MEASURES: Amplitude of rectus femoris activity in the loading response phase and the pre- and initial-swing phase during walking at four speeds. RESULTS: There was a bimodal pattern of rectus femoris activity in all subjects, at all speeds, in both phases, with high variability in the onsets, durations, and amplitudes of activity, and paired t tests revealed no significant differences (p > .05) between phases at any walking speed. CONCLUSION: Activity in the rectus femoris in the pre- and initial-swing phase in nondisabled individuals at all speeds suggests that similar activity detected in individuals with stiff-legged gait may not be inappropriate.
