Ju Seok Ryu

Association between Cross-sectional Areas of Lumbar Muscles on Magnetic Resonance Imaging and Chronicity of Low Back Pain

Objective To investigate the prognostic value of cross-sectional areas (CSA) of paraspinal (multifidus and erector spinae) and psoas muscles on magnetic resonance imaging (MRI) in chronicity of low back pain. Method Thirty-eight subjects who visited our hospital for acute low back pain were enrolled. Review of their medical records and telephone interviews were done. Subjects were divided into two groups; chronic back pain group (CBP) and a group showing improvement within 6 months after onset of pain (IBP). The CSA of paraspinal and psoas muscles were obtained at the level of the lower margin of L3 and L5 vertebrae using MRI. Results CSA of erector spinae muscle and the proportion of the area to lumbar muscles (paraspinal and psoas muscles) at L5 level in the CBP group were significantly smaller than that of the IBP group (p<0.05). The mean value of CSA of multifidus muscle at L5 level in the CBP group was smaller than that of the IBP group, but was not statistically significant (p>0.05). CSA of psoas muscle at L5 level and all values measured at L3 level were not significantly different between the groups (p>0.05). Conclusion CSA of erector spinae muscle at the lower lumbar level and the proportion of the area to the lumbar muscles at the L5 level can be considered to be prognostic factors of chronicity of low back pain.

Findings of Abnormal Videofluoroscopic Swallowing Study Identified by High-Resolution Manometry Parameters

OBJECTIVE To identify the parameters of high-resolution manometry (HRM) with a significant correlation to abnormal findings of videofluoroscopic swallowing study (VFSS). DESIGN Prospective study. SETTING Hospital rehabilitation department. PARTICIPANTS Patients with dysphagia symptoms (N=40). INTERVENTION Participants were evaluated once using VFSS in neutral head position and evaluated twice using HRM with 5mL of thin fluid. MAIN OUTCOME MEASURES HRM parameters included maximal pressure, area integral, rise time, duration of the velopharynx and tongue base, maximal pressure of pre-upper esophageal sphincter (UES), low pharynx, cricopharyngeus, minimal UES pressure, UES activity time, and nadir UES duration. HRM parameters were compared with the findings of VFSS. Receiver operating characteristic analysis was performed to obtain the cutoff value, sensitivity, and specificity of HRM parameters for the prediction of findings of VFSS. RESULTS The maximum pressure of the velopharynx showed a significantly positive prediction for most abnormal parameters of VFSS in the pharyngeal phase. Nadir UES pressure duration was significant for impaired laryngeal elevation, residue at pyriformis sinus, and combination of penetration and aspiration. The maximum pressure of the velopharynx <180.0 showed 100% sensitivity and 75% specificity for the presence of penetration and aspiration, and the cutoff point of 178.8 showed 86.7% sensitivity and 75% specificity for the presence of subglottic aspiration. CONCLUSIONS This study identified significant HRM parameters that are highly specific for individual abnormalities of VFSS, suggesting the cutoff value, sensitivity, and specificity. Because HRM could inform the quantitative measurement of pharyngeal weakness, the cutoff value for HRM parameters could be used to predict aspiration in patients with pharyngeal weakness.

Intraoperative facial electromyography and brainstem auditory evoked potential findings in microvascular decompression for hemifacial spasm: correlation with postoperative delayed facial palsy.

Background: Delayed facial palsy (DFP) after microvascular decompression (MVD) in patients with hemifacial spasm (HFS) is not uncommon, but the cause remains unknown. Objectives: To assess whether intraoperative electromyography (EMG) and brainstem auditory evoked potential (BAEP) can predict DFP after MVD. Methods: Between September 2009 and February 2011 we examined 86 patients, 9 of whom (10.4%) developed DFP after MVD on the same side. All patients underwent MVD and were followed-up for a median period of 13 months (range 6–22). We retrospectively examined intraoperative facial EMG and BAEP findings using our MVD patients’ registry. We excluded secondary HFS and immediate postoperative facial palsy after MVD in this study. We assessed the prevalence and clinical characteristics of DFP and compared EMG and BAEP findings between DFP and non-DFP groups. Results: All patients recovered completely, with a mean time to recovery of 37.8 days (range 22–57). There were no significant differences between DFP and non-DFP patients in terms of the amplitude and latency of intraoperative EMG and BAEP. Conclusion: The usefulness of intraoperative facial EMG and BAEP is limited and cannot predict DFP after MVD for HFS. We speculate that DFP after MVD is not associated with permanent nerve damage according to the EMG findings.

The Effects of Bolus Volume and Texture on Pharyngeal Pressure Events Using High-resolution Manometry and Its Comparison with Videofluoroscopic Swallowing Study.

Background/Aims The purpose of this study was to develop new parameters of high-resolution manometry (HRM) and to applicate these to quantify the effect of bolus volume and texture on pharyngeal swallowing. Methods Ten healthy subjects prospectively swallowed dry, thin fluid 2 mL, thin fluid 5 mL, thin fluid 10 mL, and drinking twice to compare effects of bolus volume. To compare effect of texture, subjects swallowed thin fluid 5 mL, yogurt 5 mL, and bread twice. A 32-sensor HRM catheter and BioVIEW ANALYSIS software were used for data collection and analysis. HRM data were synchronized with kinematic analysis of videofluoroscopic swallowing study (VFSS) using epiglottis tilting. Results Linear correlation analysis for volume showed significant correlation for area of velopharynx, duration of velopharynx, pre-upper esophageal sphincter (UES) maximal pressure, minimal UES pressure, UES activity time, and nadir UES duration. In the correlation with texture, all parameters were not significantly different. The contraction of the velopharynx was faster than laryngeal elevation. The durations of UES relaxation was shorter in the kinematic analysis than HRM. Conclusions The bolus volume was shown to have significant effect on pharyngeal pressure and timing, but the texture did not show any effect on pharyngeal swallowing. The parameters of HRM were more sensitive than those of kinematic analysis. As the parameters of HRM are based on precise anatomic structure and the kinematic analysis reflects the actions of multiple anatomic structures, HRM and VFSS should be used according to their purposes.

Facilitating Effects of Fast and Slope Walking on Paraspinal Muscles

Objective To quantify the activation of the paraspinalis muscles (multifidus and erector spinae) at different walking velocities and slope with surface electromyography. Methods This study was a prospective experimental study involving ten healthy male participants. Surface electrodes were placed over the multifidus and erector spinae muscles at the L5 and L3 level. After the electrode was placed at the lumbar paraspinalis muscles, electromyography signals were recorded over 20 seconds. Data were collected three times during the walking exercise at a 0° gradient with the speed from 3 to 6 km/hr. At 7° gradient and 15° gradient, data were also collected three times but a walking speed of 4 km/hr. The area under the curve was calculated for quantitative measurement of muscle activation. Results While the muscle activation was increased at higher walking velocities at the L5 and L3 levels of the multifidus, the erector spinae muscle activation did not show any change at higher walking velocities. At L3 level of the multifidus and erector spine muscles, the muscle activation was significantly increased in 15° gradient compared to those seen in at 0° gradient. At L5 level, the multifidus and erector spinae muscle activation in 0° gradient was not significantly different from that those seen in 7° or 15° gradient. Conclusion Fast walking exercise activates lumbar multifidus muscles more than the slow walking exercise. Also, the mid lumbar muscles are comparatively more activated than low lumbar muscles when the walking slope increases.

Electromyographic Changes in Trunk Muscles During Graded Lumbar Stabilization Exercises

Lumbar stabilization exercises are effective for the treatment of patients with low back pain. However, personalized exercise programs are required to facilitate more efficient treatment, as each individual exhibits the different characteristics of the trunk muscles and pain.

Effects of Head Rotation and Head Tilt on Pharyngeal Pressure Events Using High Resolution Manometry

Objective To observe changes in pharyngeal pressure during the swallowing process according to postures in normal individuals using high-resolution manometry (HRM). Methods Ten healthy volunteers drank 5 mL of water twice while sitting in a neutral posture. Thereafter, they drank the same amount of water twice in the head rotation and head tilting postures. The pressure and time during the deglutition process for each posture were measured with HRM. The data obtained for these two postures were compared with those obtained from the neutral posture. Results The maximum pressure, area, rise time, and duration in velopharynx (VP) and tongue base (TB) were not affected by changes in posture. In comparison, the maximum pressure and the pre-upper esophageal sphincter (UES) maximum pressure of the lower pharynx in the counter-catheter head rotation posture were lower than those in the neutral posture. The lower pharynx pressure in the catheter head tilting posture was higher than that in the counter-catheter head tilting. The changes in the VP peak and epiglottis, VP and TB peaks, and the VP onset and post-UES time intervals were significant in head tilting and head rotation toward the catheter postures, as compared with neutral posture. Conclusion The pharyngeal pressure and time parameter analysis using HRM determined the availability of head rotation as a compensatory technique for safe swallowing. Tilting the head smoothes the progress of food by increasing the pressure in the pharynx.

High Resolution Manometry Analysis of a Patient With Dysphagia After Occiput-C3/4 Posterior Fusion Operation

Many reports of changes in cervical alignment after posterior occipitocervical (O-C) fusion causing dysphagia are available. The clinical course can range from mild discomfort to severe aspiration. However, the underlying pathogenesis is not well known. We report an 80-year-old female with videofluoroscopic swallowing study evidence of aspiration that developed after occiput-C3/4 posterior fusion. Pharyngeal pressure was analyzed using high resolution manometry (HRM). Impaired upper esophageal sphincter opening along with diminished peristalsis and pharyngeal pressure gradient were revealed by HRM to be the main characteristics in such patients. The patient fully recovered after a revision operation for cervical angle correction. Distinct pressure patterns behind reversible dysphagia caused by a change in cervical alignment were confirmed using HRM analysis.

Effect of Different Viscosities on Pharyngeal Pressure During Swallowing: A Study Using High-Resolution Manometry

OBJECTIVES To investigate and compare the mechanism of swallowing with respect to the viscosity of ingested material between patients with and without dysphagia. DESIGN Prospectively collected and retrospectively analyzed clinical study. SETTING General teaching hospital, rehabilitation unit. PARTICIPANTS We retrospectively reviewed the high-resolution manometry (HRM) results of 35 patients with dysphagia symptoms (N=35). Additionally, we included 18 patients without dysphagia. Based on videofluoroscopic swallowing study results, we classified the patients into 2 groups: one with aspiration and the other without aspiration. INTERVENTION Swallowing of a 5-mL thin liquid and 5-mL honey-like liquid in all patients. MAIN OUTCOME MEASURE HRM of various variables during the swallowing process. RESULTS There was no significant difference between the thin liquid and honey-like liquid with respect to parameters for HRM in the patients without dysphagia and in the nonaspiration and aspiration groups. However, in a comparison between thin liquid and honey-like liquid with respect to visuospatial and timing variables, the degree of differences in the maximal pressure of the velopharynx in the aspiration group was significantly larger than the patients without dysphagia and the nonaspiration group (P<.05). CONCLUSIONS Our results indicate that there is a clear difference in the degree of adaptation to viscosity between the 3 groups-patients without dysphagia, patients with aspiration, and patients without aspiration. These differences may provide an explanation for the mechanism of swallowing, which may be useful for the treatment of dysphagia.

Poster 144 The Graded Effects of Lumbar Stabilization Exercises and Its Verification Using Electromyography

Disclosures: D. Park: I Have No Relevant Financial Relationships To Disclose. Objective: To determine the effects of graded lumbar stabilization exercises on lumbar stabilizing muscles. Design: Cross-sectional study. Setting: Tertiary teaching hospital. Participants: Ten healthy males. Interventions: Five common exercises for strengthening the lumbar stabilizing muscles were selected: curl up, dead bug, side bridge, superman and bird dog exercises. And each exercise was divided into five levels by varied level of intensity. Main Outcome Measures: Using superficial electromyography, the electrical activity of rectus abdominis (RA), external oblique abdominis (EO), multifidus (MF) and erector spinae (ES) muscles was recorded during the exercise. The areas under the curve which were adjusted to different duration and peak amplitude were calculated. The Kruskal Wallis test and the post-hoc test with Mann-Whitney test were used. Results or Clinical Course: As the level of intensity of each exercise increased, the activity of related lumbar stabilizing muscles was generally increased. In detail, the activity of RA and EO was distinctly increased when trunk curl was added to neck flexed or supine position in the curl up exercise. However the posture of upper extremities didn’t influence the activity change of recorded lumbar stabilizing muscles. In the dead bug posture, the activities of RA, EO and MF were more increased while performing both arm and leg movements rather than arm or leg movement alone. In the side bridge posture, when leg abduction was added, mean area of MF was significantly increased. In the prone posture, lengthening the duration of the superman exercise increased the mean area of MF, ES and RA. In the bird dog posture, the activities of ES and MF were more increased while performing both arm and leg lifts rather than arm or leg lift alone. Conclusion: The graded lumbar stabilization exercises could be effective ways to strength muscles and increase the patient compliance. According to the physical ability of patients, they will be prescribed the proper level of the exercise intensity, and also only small numbers of exercise were needed to educate, instead of various kinds of different lumbar stabilization exercises.