Is there a relationship between light touch-pressure sensation and functional hand ability?

Age related changes in skin sensitivity assessed with smartphone vibration testing

The capacity to perceive tactile input at the fingertips, referred to as tactile sensitivity, is known to diminish with age due to regressive changes to mechanoreceptor density and morphology. Sensitivity is measured as perceptual responses to stimuli of varying intensity. Contrary to traditional sensitivity monitoring instruments, smartphones are uniquely suited for remote assessment and have shown to deliver highly calibrated stimuli along a broad spectrum of intensity, which may improve test reliability. The aim of this study was to evaluate a vibration-emitting smartphone application, the Vibratus App, as a mode of estimating tactile sensory thresholds in the aging adult. The peripheral nerve function of 40 neurologically healthy volunteers (ages 18-71) was measured using monofilaments, a 128-Hz tuning fork, the Vibratus App, and nerve conduction studies (NCS). Between group differences were analyzed to determine each measurement's sensitivity to age. Spearman correlation coefficients depicted the associative strength between hand-held measurements and sensory nerve action potential (SNAP) amplitude. Inter-rater reliability of traditional instruments and the software-operated smartphone were assessed by intraclass correlation coefficient (ICC2,k). Measurements taken with Vibratus App were significantly different between age groups (p < 0.001). The inter-rater reliability of monofilament, smartphone vibration, and tuning fork testing was moderate to good (ICC2,k = 0.65, 0.69, and 0.79, respectively). The findings of this study support further investigation of smartphones as sensitivity monitoring devices for at home monitoring of skin sensitivity.

Are the sensorimotor control capabilities of the hands the factors influencing hand function in people with schizophrenia?

BACKGROUND

Previous works reported people with schizophrenia experienced inferior hand functions which influence their daily participation and work efficiency. Sensorimotor capability is one of indispensable elements acting in a well-executed feed-forward and feedback control loop to contribute to hand performances. However, rare studies investigated contribution of sensorimotor ability to hand functions for people with schizophrenia. This study aimed to explore hand function in people with schizophrenia based on the perspective of the sensorimotor control capabilities of the hands.

METHODS

Twenty-seven people at the chronic stage of schizophrenia were enrolled. The following assessment tools were used: the Purdue Pegboard Test (PPT) and the VALPAR Component Work Sample-8 (VCWS 8) system for hand function; the Self-Reported Graphic version of the Personal and Social Performance (SRG-PSP) scale for functionality; and the Semmes-Weinstein Monofilaments (SWM), the pinch-holding-up-activity (PHUA) test and the Manual Tactile Test (MTT) for the sensory and sensorimotor parameters. The Clinical Global Impression-Severity (CGI-S) scale and the Extrapyramidal Symptom Rating Scale (ESRS) were used to grade the severity of the illness and the side-effects of the drugs. Spearman's rank correlation coefficient was used to analyze associations among hand function, functionality, and sensorimotor capabilities. A multiple linear regression analysis was used to identify the determinants of hand function.

RESULTS

The results indicated that both hand function and sensorimotor capability were worse in people with schizophrenia than in healthy people, with the exception of the sensory threshold measured with the SWM. Moreover, the sensorimotor abilities of the hands were associated with hand function. The results of the regression analysis showed that the MTT measure of stereognosis was a determinant of the PPT measure of the dominant hand function and of the performance on the VCWS 8, and that the ESRS and the MTT measure of barognosis were determinants of the performance on the assembly task of the PPT.

CONCLUSIONS

The findings suggested that sensorimotor capabilities, especially stereognosis and barognosis, are crucial determinants of hand function in people with schizophrenia. The results also revealed that the side effects of drugs and the duration of the illness directly affect hand function.

CLINICAL TRAIL REGISTRATION

ClinicalTrials.gov , identifier NCT04941677, 28/06/2021.

Skin Sensitivity Assessment Using Smartphone Haptic Feedback

Goal: This work presents a smartphone application to assess cutaneous sensory perception by establishing Vibrational Perception Thresholds (VPTs). Cutaneous sensory perception diagnostics allow for the early detection and symptom tracking of tactile dysfunction. However, lack of access to healthcare and the limited frequency of current screening tools can leave skin sensation impairments undiscovered or unmonitored. Methods: A 23-participant cross-sectional study in subjects with a range of finger sensation tests Smartphone Established VPTs (SE-VPTs) by varying device vibrational intensity. These are compared against monofilament test scores, a clinical measure of skin sensitivity. Results: We find a strong positive correlation between SE-VPTs and monofilament scores ([Formula: see text] = 0.86, p = 1.65e-07). Conclusions: These results demonstrate the feasibility of using a smartphone as a skin sensation screening tool.

Identification of Optimal Foot Tactile Sensation Threshold for Detecting Fall Risk Among Community-Dwelling Older Adults

OBJECTIVE

Foot tactile sensitivity loss, commonly assessed by monofilaments, is a fall risk factor among older adults. The broadly used threshold of the monofilament for fall risk assessment in older adults is 5.07. However, this threshold originates from assessing foot ulceration risk in people with peripheral neuropathy. The primary purpose of this study was to identify the optimal filament size and its cutoff number of sensitive sites that can be used to best identify a high risk of falls in terms of the foot tactile sensitivity for community-dwelling older adults.

METHODS

In this cross-sectional study, the foot tactile sensitivity was assessed by a 6-piece Semmes-Weinstein monofilament kit at 9 sites per foot among 94 older adults, including 38 fallers and 56 nonfallers. The number of sensitive sites was determined for each monofilament size as the cutoff. Logistical regression analyses were used to determine the monofilament size and number of sensitive sites best able to differentiate fallers from nonfallers.

RESULTS

Fallers showed overall worse foot tactile sensory measurements than nonfallers. Logistical regression analyses identified 4.31 as the best monofilament size and 7 as the number of sensitive sites to differentiate fallers from nonfallers with an accuracy of 71.3%.

CONCLUSION

The 4.31 monofilament could be the best filament to detect the risk of falls among older adults in terms of tactile sensory loss. Inability to feel the pressure from the 4.31 filament at more than 7 sites could indicate a high risk of falls.

IMPACT

These findings could help physical therapists and other rehabilitation professionals improve decision making in detecting older adults with a high risk of falls, thus facilitating the effort of fall prevention in older adults.

Anticipation and compensation for somatosensory deficits in object handling: evidence from a patient with large fiber sensory neuropathy

The purpose of this study was to determine the contributions of feedforward and feedback processes on grip force regulation and object orientation during functional manipulation tasks. One patient with massive somatosensory loss resulting from large fiber sensory neuropathy and 10 control participants were recruited. Three experiments were conducted: 1) perturbation to static holding; 2) discrete vertical movement; and 3) functional grasp and place. The availability of visual feedback was also manipulated to assess the nature of compensatory mechanisms. Results from experiment 1 indicated that both the deafferented patient and controls used anticipatory grip force adjustments before self-induced perturbation to static holding. The patient exhibited increased grip response time, but the magnitude of grip force adjustments remained correlated with perturbation forces in the self-induced and external perturbation conditions. In experiment 2, the patient applied peak grip force substantially in advance of maximum load force. Unlike controls, the patient's ability to regulate object orientation was impaired without visual feedback. In experiment 3, the duration of unloading, transport, and release phases were longer for the patient, with increased deviation of object orientation at phase transitions. These findings show that the deafferented patient uses distinct modes of anticipatory control according to task constraints and that responses to perturbations are mediated by alternative afferent information. The loss of somatosensory feedback thus appears to impair control of object orientation, whereas variation in the temporal organization of functional tasks may reflect strategies to mitigate object instability associated with changes in movement dynamics.NEW & NOTEWORTHY This study evaluates the effects of sensory neuropathy on the scaling and timing of grip force adjustments across different object handling tasks (i.e., holding, vertical movement, grasping, and placement). In particular, these results illustrate how novel anticipatory and online control processes emerge to compensate for the loss of somatosensory feedback. In addition, we provide new evidence on the role of somatosensory feedback for regulating object orientation during functional prehensile movement.

The Use of Quantitative Sensation Testing to Identify the Physiological Differences Between the Median and Ulnar Nerves

Introduction

Similarities in morphology, physiological function, and neurophysiological findings between median and ulnar nerves are not unequivocal. Our previous study confirmed differences in motor fiber parameters between these nerves in healthy persons. We made an attempt to assess and compare the physiological parameters of different sensation modalities (temperature, pain, and vibration) in median and ulnar nerves.

Methods

The study was performed in 31 healthy, right-handed volunteers: 17 women, 14 men, mean age 44.8 ± 15.5 years. Standard sensory conduction tests in the median and ulnar nerves were performed together with the estimation of vibratory, temperature, and warm- and cold-induced pain thresholds in the C7 and C8 dermatomes on the palm, using quantitative sensory testing.

Results

There were no statistically significant differences in the standard sensory conduction test in the median and ulnar nerves across the whole group: between right and left hands, and between women and men. We revealed differences in the temperature and pain thresholds between these nerves, mainly in low temperature perception. There were no differences in estimated thresholds between sides or in female and male groups. The vibratory limits did not differ significantly between nerves, and subgroups.

Conclusion

The study confirmed the differences in the physiological sensory perception between the median and ulnar nerves. The median nerve is more sensitive to temperature stimulation than the ulnar nerve, but simultaneously less sensitive to pain-inducing temperature stimuli. These findings should be considered during the examination of hand nerve pathology.

Relationship between nerve conduction studies and the Functional Dexterity Test in workers with carpal tunnel syndrome

Background

Dexterity impairments caused by carpal tunnel syndrome (CTS) make working and daily activities challenging. We aimed to investigate: i) the relationship between dexterity and nerve conduction studies (NCS) in workers with classic symptoms presentation; ii) the ability of the Functional Dexterity Test (FDT) to discriminate different levels of CTS severity as classified by NCS; iii) the diagnostic accuracy of a clinical battery composed of the FDT, Phalen’s test and Tinel’s sign.

Methods

In a convenience sample of individuals diagnosed with CTS, we correlated FDT net scores with the NCS-based classification by means of Spearman’s (rho) test. Discriminative ability of the FDT was assessed by ANOVA, and a ROC curve determined cutoff thresholds. Sensitivity, specificity, and likelihood ratios (LRs) were used to investigate the diagnostic accuracy of the clinical battery.

Results

Data from 180 hands were collected. The FDT was significantly correlated (rho = 0.25, p <  0.001) with NCS. The FDT was able to discriminate subjects with severe/extreme NCS findings, and two thresholds (0.29–0.36) were identified. Adding the FDT to the provocative tests improved the overall diagnostic accuracy (specificity: 0.97, CI_95% 0.83–0.99; LR+: 14.49, CI_95% 2.09–100.53).

Conclusions

Sensorimotor impairments related to CTS can affect hand dexterity. The FDT discriminated patients with severe NCS involvement. Positive results on the clinical battery (Phalen, Tinel, and FDT) could help to confirm the CTS diagnosis, showing a very high specificity and LR+. On the contrary, the low sensitivity is not able to rule out CTS in individuals with negative results.

Sensory retraining improves light touch threshold of the paretic hand in chronic stroke survivors: a single-subject A-B design

Background: Light touch, one of the primary and basic sensations, is often neglected in sensory retraining programmes for stroke survivors.Objective: This study aimed to investigate the effects of sensory retraining on the light touch threshold of the hand, dexterity and upper limb motor function of chronic stroke survivors.Methods: Five chronic stroke survivors with sensory impairment participated in this single-subject A-B design study. In baseline (A) phase, they only received standard rehabilitation. In the treatment (B) phase, they received a 6-week sensory retraining intervention in addition to standard rehabilitation. In both phases, they were evaluated every 3 days. Light touch threshold, manual dexterity and upper limb motor function were assessed using Semmes-Weinstein Monofilaments, Box-Block Test and Fugl-Meyer Assessment, respectively. Visual analysis, nonparametric Mann-Whitney U test and, c-statistic were used for assessing the changes between phases.Results: All participants indicated changes in trend or slope of the total score of light touch or both between the two phases. The results of the c-statistic also showed the statistical difference in the total score of light touch between baseline and treatment in all participants (p < 0.001). Also, the results of the c-statistic and Mann-Whitney U test supported the difference of manual dexterity and motor function of the upper limb between baseline and treatment in all participants (p < 0.001).Conclusion: Current findings showed that sensory retraining may be an effective adjunctive intervention for improving the light touch threshold of the hand, dexterity and upper limb motor function in chronic stroke survivors.

Beneficial Effects of Pulsed Electromagnetic Field during Cast Immobilization in Patients with Distal Radius Fracture

To assess whether pulsed electromagnetic field therapy during cast immobilization of distal radius fractures has beneficial effects on pain and limb function, the study included 52 patients (mean age 60.8 ± 15.0 years) with distal radius fractures treated with cast immobilization. Patients were allocated to a pulsed electromagnetic field group (n = 27) or a control group (n = 25). Pain; forearm and arm circumference; range of motion; disabilities of the arm, shoulder, and hand score; and touch sensation were evaluated on the day of the plaster cast dressing and 3 and 6 weeks after. In comparison to the control group, the pulsed electromagnetic field group reported significant changes after 3 and 6 weeks of treatment: lower pain levels (p=0.0052; p < 0.0001, respectively), greater mobility of upper-limb joints, improvement in exteroceptive sensation, and reduction in disability of the upper limb (disabilities of the arm, shoulder, and hand) (p=0.0003; p < 0.0001, respectively). Our results suggest that early addition of pulsed electromagnetic field treatment, during cast immobilization of distal radius fractures, has beneficial effects on the pain, exteroceptive sensation, range of motion, and daily functioning of patients.

Hand-eye coordination, movement reaction time and hand tactile sensitivity depending on the practiced sports discipline

BACKGROUND

Practicing competitive sports, particularly those disciplines in which the upper limbs are involved in the movement, develops physical fitness and its special feature, namely the hand-eye coordination. Some sport disciplines require manipulation of an object. Using a sport equipment every day, several times, during training and matches must affect the characteristics of the skin of the palmar side of the hand. It may be presumed to affect the tactile sensitivity of the skin. The aim of the study was to determine the relationship between hand-eye coordination and tactile sensitivity in basketball, volleyball, handball, football and combat sports players as compared to those who do not practice competitive sports.

METHODS

Overall, 121 men were subject to tests. The tactile sensitivity threshold was determined at three points of the palmar side of the hand using The Touch-Test™ Sensory Evaluators esthesiometer. The second test involved hand-eye coordination of the upper limbs and it was carried out using cross-type machine.

RESULTS

The greatest tactile sensitivity was shown in combat sports players. These players also demonstrated the shortest reaction time and the lowest number of errors in the motor coordination test. The correlation between tactile sensitivity and coordination was found to be the strongest in subjects not practicing sports.

CONCLUSIONS

The most interesting finding is that in the group of athletes using hands (team sports games and combat sports) the correlation between movement coordination and tactile sensitivity is weaker.

Effects of the Surface Texture and Weight of a Pinch Apparatus on the Reliability and Validity of a Hand Sensorimotor Control Assessment

OBJECTIVES

To investigate the reliability and validity of a modified pinch apparatus devised with 3 surface textures and 2 different weights for clinical application.

DESIGN

Case-controlled study.

SETTING

A university hospital.

PARTICIPANTS

The participants (N=32) included carpal tunnel syndrome (CTS) patients (n=16) with 20 sensory neuropathy hands, and an equal number of age-sex matched volunteers without CTS, as well as young volunteers without CTS (n=16 with 20 hands) used to analyze both the testing validity and reliability of the modified device.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The Semmes-Weinstein monofilament (SWM) and two-point discrimination (2PD) tests were conducted, and the force ratio between the FP_peak (peak pinch force during lifting phase) and FL_max (maximum load force at maximum upward acceleration onset) detected from a pinch-holding-up activity (PHUA) under various testing conditions was obtained.

RESULTS

The range of the intraclass correlation coefficient of this pinch device was 0.369-0.952. The CTS patients exhibited poorer force modulation ability according to the inertial change in a dynamic lifting task when compared to the controls under all testing conditions (P<.001). The area under the receiver operating characteristic force ratio curve was 0.841, revealing high accuracy of the test for diagnosing CTS neuropathic hands under the testing condition in which the 125-g coarse texture device was used. In addition, the weight factor was shown to have significant effects on the sensitivity and accuracy of the PHUA assessment.

CONCLUSIONS

This study showed that the PHUA test via the modified pinch apparatus is a sensitive tool that can be used in clinical practice for detecting neuropathic CTS hands. In addition, changing the weight of the pinch device has a significant effect on the sensitivity and accuracy of the PHUA assessment.

Validity and reliability of the Functional Dexterity Test in children

STUDY DESIGN

Clinical measurement study.

INTRODUCTION

The Functional Dexterity Test (FDT) has not been validated in children.

PURPOSE OF THE STUDY

To determine reliability and validity of the FDT in a pediatric population.

METHODS

Intraclass Correlation Coefficients (ICCs) were used to calculate interrater and test-retest reliability in typically developing children. Pearson correlation coefficients were used to compare FDT speed with the Jebsen-Taylor Hand Function Test (JHFT) and with 2 activities of daily living tasks to establish validity in children with congenital hand differences.

RESULTS

The FDT demonstrated excellent interrater (ICC, 0.99) and test-retest (ICC, 0.90) reliability. Pearson correlation coefficients exceeded 0.67 for JHFT subsets of fine dexterity and were all less than 0.66 for JHFT subsets of gross grasp. Correlations with the activities of daily living tasks were good to excellent. FDT speeds in TD children exceeded those of children with congenital hand differences (P < .001), demonstrating discriminant validity.

DISCUSSION

Children with congenital hand differences are often treated early in life, making it important to reliably assess hand function of these young children to distinguish developmental change from changes due to interventions. The FDT can reliably measure functional progress over time, help clinicians monitor the efficacy of treatment, and provide families realistic feedback on their child's progress.

CONCLUSION

The FDT is a valid and reliable instrument for the measurement of fine motor dexterity in children.

Assessment of dexterity and diagnostic accuracy of the Functional Dexterity Test in patients with carpal tunnel syndrome

BACKGROUND

The diagnosis of carpal tunnel syndrome (STC) is centered on the symptoms. However, patients also show an impairment of sensorimotor functions, but the relationship between STC and manual dexterity has never been investigated.

OBJECTIVES

To analyze the correlation between manual dexterity and severity of the STC. Another objective was the diagnostic accuracy of the clinical battery including provocative tests (Phalen, Tinel) and Functional Dexterity Test (FDT).

METHODS

A sample of 80 subjects with suspected STC was subdivided into 4 groups based on EMG (severe/extreme-GrA, moderate-GrB, mild/minimal-GrC, negative-GrD) and evaluated in blind by Phalen, Tinel and FDT. The relationship between the FDT and the allocation of subjects was investigated by Spearman's rho, while the groups were compared with univariate ANOVA and Tukey's post hoc analysis. Diagnostic accuracy of the clinical battery was expressed by sensitivity, specificity, and likelihood ratios (LR).

RESULTS

A moderate (r=0.48, p minor of 0.001) correlation was found between FDT and the 4 groups. ANOVA has returned a significant difference between GrA vs. all others and between GrB vs. GrD. The battery showed a sensitivity, specificity, positive likelihood ratio (LR+) and negative likelihood ratio (LR-) of 70%, 94%, 11.98 and 0.31 respectively.

CONCLUSIONS

The results of this study supported the hypothesis that STC patients also have a dexterity impairment. The FDT was able to discriminate between three levels of severity (negative, mild to moderate, severe to extreme), maintaining a good level of diagnostic accuracy in addition to provocative tests.

Sensorimotor performance and function in people with osteoarthritis of the hand: A case-control comparison

OBJECTIVES

To determine whether hand left/right judgements, tactile acuity, and body perception are impaired in people with hand OA. To examine the relationships between left right judgements, tactile acuity and hand pain. To explore the relationships between sensorimotor measures (left/right judgements and tactile acuity) and measures of hand function in people with hand OA.

METHODS

Twenty patients with symptomatic hand OA and 19 healthy pain-free controls undertook a hand left/right judgment task, a control left/right judgement task, two-point discrimination (TPD) threshold testing (assessing tactile acuity), a neglect-like symptoms questionnaire (assessing body perception) and several established measures of hand function.

RESULTS

Neglect-like symptoms were experienced more frequently in the hand OA group (P < 0.05). People with hand OA were slower (P < 0.05) and less accurate (P < 0.05) in the hand left/right judgement task when compared to healthy controls, with no significant difference in the control task. Significant associations were found between hand left/right judgement reaction time and pain intensity (P < 0.05) and accuracy and pain intensity (P < 0.05). TPD was not different between groups, and no correlation was found between TPD and left/right judgement performance. No association was found between left/right judgement performance and measures of hand function (all P > 0.05). However, TPD (tactile acuity) was related to several measures of hand function (all P < 0.05).

CONCLUSION

People with hand OA had more frequent neglect-like symptoms and were slower and less accurate compared to healthy controls at hand left/right judgments, which was indicative of disrupted working body schema. Future studies may wish to examine whether interventions targeting sensorimotor dysfunction are effective at reducing pain and improving hand function and dexterity in people with hand OA.

Hand Sensorimotor Function in Older Children With Neonatal Brachial Plexus Palsy

BACKGROUND

Routine sensory assessments in neonatal brachial plexus palsy are infrequently performed because it is generally assumed that sensory recovery exceeds motor recovery. However, studies examining sensory function in neonatal brachial plexus palsy have produced equivocal findings. The purpose of this study was to examine hand sensorimotor function in older children with neonatal brachial plexus palsy using standard clinical and research-based measures of tactile sensibility.

METHODS

Seventeen children with neonatal brachial plexus palsy (mean age: 11.6 years) and 19 age-matched controls participated in the study. Functional assessments included grip force, monofilament testing, and hand dexterity (Nine-Hole Peg, Jebsen-Taylor Hand Function). Tactile spatial perception involving the discrimination of pin patterns and movement-enhanced object recognition (stereognosis) were also assessed.

RESULTS

In the neonatal brachial plexus palsy group, significant deficits in the affected hand motor function were observed compared with the unaffected hand. Median monofilament scores were considered normal for both hands. In contrast, tactile spatial perception was impaired in the neonatal brachial plexus palsy group. This impairment was seen as deficits in both pin pattern and object recognition accuracy as well as the amount of time required to identify patterns and objects. Tactile pattern discrimination time significantly correlated with performance on both functional assessment tests (P < 0.01).

DISCUSSION

This study provides evidence that tactile perception deficits may accompany motor deficits in neonatal brachial plexus palsy even when measures of tactile registration (i.e., monofilament testing) are normal. These results may reflect impaired processing of somatosensory feedback associated with reductions in goal-directed upper limb use and illustrate the importance of including a broader range of sensory assessments in neonatal brachial plexus palsy.

Tactile sensitivity on the hands skin in rheumatic patients

Introduction

Clinical symptoms of rheumatic diseases can cause changes in the level of skin tactile sensitivity.

Aim

To determine the tactile threshold of the hands in female patients with rheumatic diseases. It also attempted to determine correlations between rheumatic patients’ tactile sensitivity and the degree of articular movement limitations, the Barthel Index (BI) and Edinburgh Handedness Inventory (EHI) results, the level of disability of the right hand and the left hand as well as age, education and eyesight.

Material and methods

Ninety-nine female rheumatic patients aged 19–87 years took part in the study. The control group comprised 45 healthy women aged 23–80 years. The measurement of the tactile threshold was performed using the Touch-Test™ Sensory Evaluators (Semmes-Weinstein Monofilaments Test). The tactile threshold was measured at three sites on the hand: the little finger, the index finger and the metacarpus.

Results

The patients’ tactile sensitivity ranges were classified as normal, diminished light touch and diminished protective touch. The degree of their disability was correlated with tactile sensitivity. The patients’ tactile sensitivity worsens with age, but it is not correlated with the level of education. The lateralization was similar to that of the control group and was not correlated with tactile sensitivity. The worsening eyesight, independent of rheumatic disease, corresponds, however, with decreasing tactile sensitivity.

Conclusions

The patients represented a group with a medium level of functional disability and lower tactile sensitivity.

The construct validity and responsiveness of sensory tests in patients with carpal tunnel syndrome

Background and Purpose :

Sensory evaluation is fundamental to evaluation of patients with Carpal Tunnel Syndrome (CTS). The purpose of this study was to determine the construct validity and responsiveness for sensory threshold tests in patients with CTS.

Methods :

Sixty-three patients diagnosed with CTS were evaluated prior to orthotic intervention and again at follow up at 6 and 12 weeks. Sensory tests included touch threshold PSSD (Pressure Specified Sensory Device) and vibration threshold (Vibrometer). Construct validity was assessed by comparing sensory tests to hand function, and dexterity testing using Spearman rho (r_s). Patients were classified as either responders or non-responders to orthotic intervention based on the change score of the Symptom Severity Scale (SSS) of 0.5. Responsiveness of the sensory tools was measured using ROC (receiver operating characteristic) curves, SRM (Standardized Response Mean), and ES (Effect Sizes).

Results :

The PSSD had low to moderate correlations (r_s ≤ 0.32) while Vibrometer scores had moderate correlations (r_s = 0.36 - 0.41) with dexterity scores. The Clinically Important Difference (CID) for the PSSD was estimated at 0.15 g/mm² but was not discriminative. The Vibrometer demonstrated moderate responsiveness, with a SRM = 0.61 and an ES = 0.46 among responders. The PSSD had a SRM = 0.09 and an ES = 0.08 and showed low responsiveness for patients with a clinically important improvement in symptoms.

Conclusion :

Measurement properties suggest that the Vibrometer was preferable to the PSSD because it was more correlated to hand function, and was more responsive. Clinicians may choose use the Vibrometer opposed to the PSSD for determining important change in sensation after orthotic intervention.

Impact of distal median neuropathy on handwriting performance for patients with carpal tunnel syndrome in office and administrative support occupations

PURPOSE

This study investigates the handwriting performance of patients with carpal tunnel syndrome (CTS) and healthy controls in office and administrative support occupations, adopting both biomechanical and functional perspectives. This work also explores how surgical intervention altered the performance of the CTS patients.

METHODS

Fourteen CTS patients and 14 control subjects were recruited to complete a self-reported survey and participate in sensory tests, hand strength, dexterity and handwriting tasks using a custom force acquisition pen along with motion capture technology. Based on the results of these, the sensory measurements, along with functional and biomechanical parameters, were used to determine the differences between the groups and also reveal any improvements that occurred in the CTS group after surgical intervention.

RESULTS

The CTS patients showed significantly poorer hand sensibility and dexterity than the controls, as well as excessive force exertion of the digits and pen tip, and less efficient force adjustment ability during handwriting. After surgery and sensory recovery, the hand dexterity and pen tip force of the CTS patients improved significantly. The force adjustment abilities of the digits also increased, but these changes were not statistically significant.

CONCLUSIONS

This study provides the objective measurements and novel apparatus that can be used to determine impairments in the handwriting abilities of office or administrative workers with CTS. The results can also help clinicians or patients to better understand the sensory-related deficits in sensorimotor control of the hand related to CTS, and thus develop and implement more suitable training or adaptive protocols.

Age-related changes in cutaneous sensation in the healthy human hand

Cutaneous sensation deteriorates with age. It is not known if this change is consistent over the entire hand or if sensation is affected by changes in skin mechanics. Cutaneous perceptual thresholds were tested at eight sites in the glabrous skin and two in the hairy skin of both hands in 70 subjects (20-88 years), five male and five female per decade, using calibrated von Frey filaments, two-point discrimination, and texture discrimination. Venous occlusion at the wrist (40 ± 10 mmHg) and moisturizer were used to alter skin mechanics. Cutaneous thresholds increased significantly with age (p < 0.001); von Frey thresholds were 0.04 g [0.02-0.07] (median and interquartile range) in the 20s and 0.16 g [0.04-0.4] in the 80s, with differences between hands for older females (p = 0.044) but not males. The pattern of changes in cutaneous sensation varied according to the site tested with smaller changes on the fingers compared to the palm. Two-point discrimination deteriorated with age (p = 0.046), but with no interaction between sex, handedness, or changes in skin mechanics. There were no significant differences for texture discrimination. Changes in skin mechanics improved cutaneous thresholds in the oldest males after moisturizing (p = 0.001) but not otherwise. These results emphasize the complex pattern of age-related deterioration in cutaneous sensation with differences between sexes, the hands, sites on the hand, and the mode of testing. As the index fingertip is not a sensitive indicator of sensory decline, the minimum assessment of age-related changes in cutaneous sensation should include both hands, and sites on the palm.

The Functional Dexterity Test: test-retest reliability analysis and up-to date reference norms

STUDY DESIGN

Clinical measurement.

INTRODUCTION

Among the available tests for fine finger dexterity, the Functional Dexterity Test (FDT) has been indicated as a valid instrument to measure outcome in different conditions.

PURPOSE OF THE STUDY

To analyze test-retest reliability, to study the influence of gender, age and hand dominance on the FDT score, and to collect reference norms for adult and elderly age-groups.

METHODS

Test-retest reliability was calculated with the Intraclass Correlation Coefficient (ICC) and Standard Error of Measurement (SEM) in a subgroup of 324 healthy volunteers. An enlarged sample of 698 subjects, tested at least once, was used to present stratified data for age group, sex, and hand dominance, and ANOVA was used to investigate statistically significant differences between groups.

RESULTS

The FDT showed excellent reliability (ICC > 0.90; SEM: <2 s for net times; <3 s for total scores). Age, gender and hand dominance significantly influenced FDT scores (p < 0.05), but no interaction between variables was found.

CONCLUSIONS

FDT is confirmed as reliable, and up-to-date reference norms over a broad range of ages of the Italian adult population have been provided.

LEVEL OF EVIDENCE

NA.

Lower touch sensibility in the extremities of healthy Indians: further deterioration with age

Touch sensibility testing is a cost-effective, psychophysical measure of peripheral nerve function and impairment. However, there is limited information regarding the natural variability in touch sensibility across different populations and different age groups. We studied 568 healthy Indian volunteers without any clinical evidence of peripheral nerve disease. Touch sensibility was evaluated bilaterally in palms, feet, and heels, using Semmes-Weinstein monofilaments, with target forces ranging from 0.008 to 300 g. No differences were observed between the right and the left limbs. The lowest target force detected ranged from 0.4 to 2 g in the palms and 1.4 to 15 g in the feet. These values showed further increase with age. Women compared with men had higher sensibility in the palms in most age groups. Touch sensibility thresholds recorded in a large group of Indians were higher than that reported in other populations. These findings have clinical implications for the diagnosis of early nerve impairment in the elderly and in disease states drawing attention to geographic variations in touch sensation.