Sensitivity and specificity of carpal tunnel syndrome signs.

The sensitivity and specificity of six carpal tunnel syndrome (CTS) signs were determined by evaluating 143 subjects (228 hands) with symptoms of CTS. Immediately after performing the six physical examination tests, standard nerve conduction studies were performed on all 228 hands to determine the presence or absence of CTS. CTS was present in 142 hands and absent in 86 hands. The signs were not very sensitive (23-69%), but were fairly specific (66-87%) for CTS. A square-shaped wrist and abductor pollicis brevis weakness were the most sensitive signs (69 and 66%, respectively), and are recommended as part of the examination of CTS. Median nerve hypesthesia and the Phalen sign both have fair sensitivity (51%) but good specificity (85 and 76%, respectively). The median nerve compression sign and the Hoffmann-Tinel sign both have poor sensitivity (28 and 23%, respectively), and thus are less helpful in evaluating subjects with suspected CTS.

Standardized nerve conduction studies in the lower limb of the healthy elderly.

Nerve conduction studies are commonly performed in elderly individuals. No complete set of reference data for the distal lower limb nerves exists for this population, making it difficult to accurately interpret electrodiagnostic findings. The purpose of this study was to provide reliable reference data by comprehensively examining conduction characteristics in routinely tested peripheral nerves of the lower limb in a healthy elderly population. Conduction studies of the tibial, deep peroneal, sural and medial dorsal cutaneous nerves were performed in one lower limb of 122 healthy elderly individuals between the ages of 60 and 89 years. Peak amplitudes of the sural sensory action potential and the tibial compound muscle action potential correlated significantly with both age and leg length. All other parameters did not show significant correlation with age. Conduction velocities and distal latencies slowed significantly with increasing leg length except for tibial distal latency.

Median and ulnar nerve conduction studies: normative data for young adults.

Temperature control and standardized technique, along with consideration of age, height, finger circumference, and instrumentation is imperative for appropriate interpretation of electrodiagnostic studies. Normative data must be based on these factors in adequate numbers of healthy subjects. This study provides comprehensive normative electrodiagnostic data for the median and ulnar nerves. Forty-four subjects participated in this study. The median motor studies showed a motor distal latency (DL) of 3.2 (0.4)msec, and distal amplitude (DAMP) of 12.1 (3.8)mV and sensory studies showed a DL of 2.5 (0.2)msec, and DAMP of 31.4 (8.7) microV for the men and 52.4 (14.3)microV for the women. The ulnar motor studies showed a motor DL of 2.6 (0.3)msec, and DAMP of 12.6 (2.3)mV and sensory studies showed a DL of 2.4 (0.2)msec, and DAMP of 27.0 (7.8)microV for the men and 52.9 (13.9)microV for the women. Sidedness and handedness did not affect the nerve conduction parameters of this study. Aging changes for these nerves were minimal but more apparent for the median nerve. The most noticeable change with aging was the decrease in amplitude of the sensory nerve action potential.

Gender and arm length: influence on nerve conduction parameters in the upper limb.

Median, ulnar, and radial nerve conduction studies (NCS) were performed in 44 subjects. Student's t-test was used to compare nerve conduction velocities (NCV), distal latencies (DL), and distal amplitudes (DAMP) for the two sexes. Only the sensory DAMPs showed statistical significance (p < .001) for gender. Women had greater mean median (52.4 microV vs 31.4 microV), ulnar (52.9 microV vs 27.0 microV), and radial (46.1 microV vs 20.1 microV) sensory DAMPs. Stepwise linear regression analysis of NCVs, DLs, and DAMPs on gender and arm length showed statistical significance only for the median (R2 = .46, p < .001), ulnar (R2 = .59, p < .001), and radial sensory DAMPs (R2 = .29, p < .001) for gender. Arm length did not account for any additional variability. Gender showed an effect on the distal sensory DAMPs obtained by antidromic technique in this study. In contrast to the reported effect of leg length and height on lower limb studies, arm length did not affect upper limb studies.

H reflex latency in the healthy elderly.

The purpose of this study was to evaluate prospectively and analyze the relationship of tibial nerve H reflex latency to age, sex, leg length, and skin temperature in a large healthy elderly population. The H reflex was recorded bilaterally in 92% of 103 carefully screened individuals aged 60-88 years. The mean H reflex latency was 30.8 (SD = 2.6) and 30.7 (SD = 2.6) ms for right and left legs, respectively. A high correlation (r = 0.55, P < 0.05) was present between H reflex latency and leg length. No significant correlation existed for H reflex latency and age. The upper normal limit for the difference between right and left H reflex latencies was 1.8 ms. This limit is greater than that reported in the literature for younger individuals due to a larger standard deviation. These findings suggest that aging increases the between-leg variability of H reflex latency in individuals. This greater difference must be taken into account when using side-to-side H reflex latency comparison to detect unilateral pathology in the elderly.

Standardized nerve conduction studies in the upper limb of the healthy elderly.

Nerve conduction studies are increasingly being performed on elderly individuals; however, no standardized data for the elderly population exists to provide an accurate interpretation of electrodiagnostic findings. The purpose of this study was to provide standardized data in the healthy elderly for the nerves of the upper limb that are routinely chosen for study by electromyographers. Nerve conduction studies were performed prospectively in one upper limb of 155 carefully screened healthy elderly individuals between the ages of 60 and 95 years. Upper limb temperature was controlled to limit the influence of temperature on the measured conduction parameters. Standard nerve conduction techniques using constant measured distances were applied to evaluate the median, ulnar and radial nerves. A normative electrodiagnostic database for elderly individuals was established in this study. The mean nerve conduction parameters of this healthy elderly population compared favorably with existing literature values for younger populations. However, age had a statistically significant but low strength effect on all ulnar nerve conduction velocities and distal latencies as well as the distal sensory amplitudes of all three nerves. Gender had a greater effect than age on these parameters as well as on median sensory distal latency. Other median motor and sensory conduction parameters along with radial sensory distal latency were not significantly related to age or gender based on two-way analysis of variance.

System for control, monitoring ensures efficient linen use.

By implementing recommendations from a short-term consulting program, a hospital regained control over the use, costs, and quality of its linen service. Long-term measures, such as use of rescheduled distribution, appropriate quotas, consistent policies, a hospital linen manager, and reports for measuring performance, have cut the costs and improved the service of the linen department.