Chin tuck for prevention of aspiration: effectiveness and appropriate posture.

Chin tuck has been has been widely used to prevent aspiration in the patients with dysphagia. This study was performed to investigate the effectiveness and the degree of optimal neck flexion of chin tuck. Ninety-seven patients who showed aspiration in the videofluoroscopic swallow study (VFSS). Participants were grouped into the effective (patients who showed effect with chin tuck) and ineffective group (those who did not show effect with chin tuck). VFSS was performed in neutral and chin tuck position and findings were compared between the groups. Severity of aspiration was assessed by the point penetration-aspiration scale. Duration of dysphagic symptoms, history of tracheostomy, and other possible contributing factors were also compared. Neck flexion angle was measured to find appropriate posture in which aspiration was prevented with chin tuck. Aspiration was reduced or eliminated in only 19 patients (19.6 %) with chin tuck. Oral transit time, pharyngeal delayed time and pharyngeal transit time were significantly shortened in both groups (p < 0.05), but the difference between the groups was not significant. Female sex and absence of residue in pyriform sinus favored the effect of chin tuck (p < 0.05). At least 17.5° of neck flexion was required to achieve an effect with chin tuck. The effectiveness of chin tuck was less than anticipated. Patients without residue in pyriform sinus were more likely to benefit from chin tuck. Sufficient neck flexion was important in chin tuck to prevent aspiration.

Inhibition of nitric oxide mediated protein nitration: therapeutic implications in experimental radiculopathy.

STUDY DESIGN: Experimental animal study. OBJECTIVE: This study investigated whether nitric oxide (NO) mediated protein nitration is involved in the pathogenesis of radiculopathy and whether the symptoms can be relieved by its suppression. SUMMARY OF BACKGROUND DATA: It has been reported that nitration of protein mediated by NO is involved in the degenerative neurological disorders, but its involvement is not clear in the radiculopathy. METHODS: Two kinds of rat models of radiculopathy were used. Radiculopathy was induced either by ligation of spinal nerve roots or transplantation of autologous nucleus pulposus. In separate groups of rats, aminoguanidine, a potent nitric oxide synthetase inhibitor, was administered just before induction of radiculopathy, to suppress NO production and resultant nitration of protein. Sensation of the hind limb was evaluated by plantar stimulation test, and motor weakness was assessed by observation of gait pattern. Nitrotyrosine, product of protein nitration, was assayed quantitatively by Western immunoblotting. RESULTS: Mechanical allodynia was observed in both compression and nucleus pulposus groups, but motor weakness was observed only in the compression group. Preoperative administration of aminoguanidine attenuated mechanical allodynia and motor weakness. Optical densities of nitrotyrosine bands increased significantly in radiculopathy groups, but they were lowered by administration of aminoguanidine. CONCLUSION: NO mediated protein nitration contributes to the development of both types of radiculopathies. Suppression of NO production can decrease protein nitration and relieve neural dysfunctions of radiculopathy. LEVEL OF EVIDENCE: N/A.

Skin temperature changes in patients with unilateral lumbosacral radiculopathy.

OBJECTIVE: To clarify the relationship of skin temperature changes to clinical, radiologic, and electrophysiological findings in unilateral lumbosacral radiculopathy and to delineate the possible temperature-change mechanisms involved. METHODS: One hundred and one patients who had clinical symptoms and for whom there were physical findings suggestive or indicative of unilateral lumbosacral radiculopathy, along with 27 normal controls, were selected for the study, and the thermal-pattern results of digital infrared thermographic imaging (DITI) performed on the back and lower extremities were analyzed. Local temperatures were assessed by comparing the mean temperature differences (ΔT) in 30 regions of interest (ROIs), and abnormal thermal patterns were divided into seven regions. To aid the diagnosis of radiculopathy, magnetic resonance imaging (MRI) and electrophysiological tests were also carried out. RESULTS: The incidence of disc herniation on MRI was 86%; 43% of patients showed electrophysiological abnormalities. On DITI, 97% of the patients showed abnormal ΔT in at least one of the 30 ROIs, and 79% showed hypothermia on the involved side. Seventy-eight percent of the patients also showed abnormal thermal patterns in at least one of the seven regions. Patients who had motor weakness or lateral-type disc herniation showed some correlations with abnormal DITI findings. However, neither pain severity nor other physical or electrophysiological findings were related to the DITI findings. CONCLUSION: Skin temperature change following lumbosacral radiculopathy was related to some clinical and MRI findings, suggesting muscle atrophy. DITI, despite its limitations, might be useful as a complementary tool in the diagnosis of unilateral lumbosacral radiculopathy.