Comparison of amplitude and area decrement in repetitive nerve stimulation.

OBJECTIVE: To access the percentage of the patients whose repetitive nerve stimulation (RNS) studies were negative for 10% amplitude decrement but positive for 10% area decrement and to compare these disagreed results with specialist physician's diagnosis. STUDY DESIGN: Retrospective descriptive study. SETTING: Electrodiagnosis laboratory, Department of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital. MATERIAL AND METHOD: All of the electromyography (EMG) reports of RNS studies were reviewed Both 10% amplitude and area decrement were used as criteria for diagnosis in each patient. The disagreed results would be compared to final diagnosis of the specialist physicians that were recorded in out-patient medical records. RESULTS: Eighty-three reports were included in the present study. Nineteen records (22.9%) were negative for 10% amplitude decrement but positive for 10% area decrement. Three records (3.6%) were positive for 10% amplitude decrement but negative for 10% area decrement. Twenty-two patients had disagreed results. Sixteen disagreed out-patient medical records (72.7%) were available for review the final specialist doctors' diagnosis. About 69% of patients, whose test was negative for 10% amplitude decrement but positive for 10% area decrement, were diagnosed as myasthenia gravis (MG) or suspected MG. All of the patients, whose test was negative for 10% area decrement but positive for 10% amplitude decrement, were diagnosed as MG. The use of both 10% amplitude and area decrement instead of 10% amplitude decrement alone will provide additional diagnostic yields in about 13% of the cases. CONCLUSION: Twenty-three percent of patients had disagreed RNS results that were negative for 10% amplitude decrement but positive for 10% area decrement. When these disagreed results were compared to the final diagnosis of specialist doctors, 69% of these patients were diagnosed or suspected and treated as MG. Using both 10% amplitude and area decrement may improve sensitivity of MG diagnosis in about 13% of the cases.

Comparison of removable rigid dressing and elastic bandage in reducing the residual limb volume of below knee amputees.

OBJECTIVE: Compare the reducing volumes of the residual limbs between the removable rigid dressing method and the elastic bandaging technique. STUDY DESIGN: Randomized controlled trial. Setting: Department of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital. MATERIAL AND METHOD: Twenty-six below-the-knee amputees (11 men (42.3%) and 15 women (57.69%)) who were informed and gave written consents were included in this study. The mean age was 68.19 +/- 10.83 years. The patients who met the eligible criteria were randomized into two groups. Fourteen subjects (53.8%) were in the EB group and 12 (46.2%) in the RRD group. The first group was taught to use a removable rigid dressing (RRD) while the second group was taught to use an elastic bandage (EB) for stump shaping and volume reduction. Both groups were trained with the same pre-prosthetic program. The circumference of the stump was measured and calculated for volume at the beginning, 2 weeks, and 4 weeks. The volume reduction was compared between the two groups. RESULTS: Twenty subjects were amputated on the right side (76.92%). The majority underlying was diabetes mellitus (80.77%). Fifteen cases of amputation were peripheral vascular disease (57.69%). The stump volume reduction of the RRD group at 2 and 4 weeks were 42.73 +/- 62.70 and 79.9 +/- 103.33 cm3, respectively. The stump volume reduction of the EB group were 21.89 +/- 118.49 and 83.03 +/- 113.05 cm3, respectively. There were no statistically significant differences of volume reduction between the two groups at 4 weeks. CONCLUSION: Removable rigid dressing had a tendency to reduce residual limb volume of below knee amputees faster than elastic bandage at 2 weeks but the decreasing volumes were not different at 4 weeks.

Effect of ultrasound thermotherapy in mild to moderate carpal tunnel syndrome.

OBJECTIVE: To investigate the efficacy of low intensity ultrasound thermotherapy, a conservative option of treatment of mild to moderate carpal tunnel syndrome (CTS). DESIGN: Prospective experimental, placebo- controlled, before-after treatment trial. SETTING: King Chulalongkorn Memorial Hospital, Outpatient Clinic and Electrodiagnostic Laboratory, Department of Rehabilitation Medicine. PATIENTS: Eighteen women, 30 hands who had clinical and electrophysiologic evidence of mild to moderate CTS. INTERVENTIONS: Patients of CTS were divided into two groups; A and B of 15 hands by random sampling. Group A was given placebo and continuous ultrasound therapy with the intensity of 0.5 W/cm2 applied to the palmar carpal tunnel for 10 minutes. Group B was given Diclofenac 75 mg/day in divided doses and sham ultrasound. The ultrasound was applied 5 days a week for 4 weeks. OUTCOME MEASURES: Each patient was clinically and electrophysiologically evaluated before and after treatment. RESULTS: There were statistically significant improvements (p < 0.05), in the clinical parameters of both groups after treatment. In the electrophysiologic study, the median SNAP amplitude was increased significantly after the treatment in ultrasound group (group A). When both groups were compared, group A had significant difference in increasing of median SNAP amplitude after treatment. CONCLUSION: The therapeutic efficacy of low intensity ultrasound thermotherapy was satisfied for mild to moderate CTS. However, the electrophysiological changes after ultrasound treatment need further investigation.