Syndromes from segmental vibration and nerve entrapment: observations on case definitions for carpal tunnel syndrome

Vibrotactile sensitivity testing for occupational and disease-induce peripheral neuropathies

The International Standard Organization (ISO) standard 13091-1 describes methods and procedures for performing the vibrotactile perception threshold (VPT) testing to diagnose changes in tactile sensory function associated with occupational exposures. However, the VPT test also has been used in the diagnosis of peripheral neuropathies associated with a number of disorders. This review examines the VPT test, variations in procedures that have been used, as well as disorders and diseases in which this test has been reliable for the detection of sensory changes. Mechanisms potentially underlying the changes in VPTs are also discussed along with procedural and subject/patient factors that may affect the interpretation of test results. Based upon the review of the literature, there are also suggestions for where additional research might improve the administration of this test, depending upon the subject/patient population and interpretation of data.

Prevalence and occupational risk factors of musculoskeletal diseases and pain among dental professionals in Western countries: A systematic literature review and meta-analysis

Background

This review aimed at examining the prevalence of musculoskeletal diseases and pain among dental professionals in Western countries. Furthermore, possible occupational risk factors were analyzed.

Methods

The literature search was conducted from June to July 2016, with an update in December 2017 using the databases MEDLINE, CINAHL, LIVIVO, Science Direct, PubMed, and Web of Science. The quality assessment was performed with a standardized instrument consisting of 10 items. A meta-analysis was carried out to compute pooled prevalence rates for musculoskeletal diseases and pain.

Results

A total of 41 studies were included in this review; 30 studies met the criteria for the meta-analysis. Prevalence rates of musculoskeletal diseases and pain among dental professionals ranged from 10.8% to 97.9%. The neck was the body region affected most often (58.5%, 95% CI = 46.0–71.0) followed by the lower back (56.4%, 95% CI = 46.1–66.8), the shoulder (43.1%, 95% CI = 30.7–55.5) and the upper back (41.1%, 95% CI = 32.3–49.9). Potential occupational risk factors included an awkward working posture, high number of treated patients, administrative work, vibration, and repetition.

Conclusions

Musculoskeletal diseases and pain are a significant health burden for dental professionals. This study showed high prevalence rates for several body regions. Therefore, suitable interventions for preventing musculoskeletal diseases and pain among dental professionals are needed.

Do exposure limits for hand-transmitted vibration prevent carpal tunnel syndrome?

BACKGROUND

An apparently high frequency of carpal tunnel syndrome (CTS) among shipyard workers undergoing health surveillance because of exposure to hand-transmitted vibration (HTV) prompted concerns that current regulatory limits on exposure might not protect adequately against the disorder.

AIMS

To explore whether within regulatory limits, higher exposures to HTV predispose to CTS.

METHODS

As part of a retrospective audit, we compared duration and current intensity of exposure to HTV in cases with new-onset CTS and controls matched for age. Conditional logistic regression was used to quantify associations, which were summarized by odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

There were 23 cases and 55 controls. After adjustment for body mass index and previous diagnosis of diabetes, no clear associations were observed either with duration of exposure to HTV or with current intensity of exposure. Risk was non-significantly elevated in men with ≥30 years' exposure to HTV (OR 1.6), but in the highest category of current exposure [8-h energy-equivalent frequency-weighted acceleration (A8) ≥ 4.0 m/s(2)], risk was lower than that in the reference category (A8 < 2.5 m/s(2)). Moreover, there was a significantly reduced risk of CTS in men with a previous diagnosis of hand-arm vibration syndrome (HAVS) (OR 0.2, 95% CI 0.1-0.9).

CONCLUSIONS

We found no evidence that below the current limit for A(8) of 5 m/s(2), higher exposures to HTV predispose to CTS. However, care should be taken not to overlook the possibility of treatable CTS when workers with diagnosed HAVS present with new or worsening sensory symptoms in the hand.

Hand-arm vibration syndrome: clinical characteristics, conventional electrophysiology and quantitative sensory testing

OBJECTIVE

Workers exposed to vibrating tools may develop hand-arm vibration syndrome (HAVS). We assessed the somatosensory phenotype using quantitative sensory testing (QST) in comparison to electrophysiology to characterize (1) the most sensitive QST parameter for detecting sensory loss, (2) the correlation of QST and electrophysiology, and (3) the frequency of a carpal tunnel syndrome (CTS) in HAVS.

METHODS

QST, cold provocation tests, fine motor skills, and median nerve neurography were used. QST included thermal and mechanical detection and pain thresholds.

RESULTS

Thirty-two patients were examined (54 ± 11 years, 91% men) at the more affected hand compared to 16 matched controls. Vibration detection threshold was the most sensitive parameter to detect sensory loss that was more pronounced in the sensitivity range of Pacinian (150 Hz, x12) than Meissner's corpuscles (20 Hz, x3). QST (84% abnormal) was more sensitive to detect neural dysfunction than conventional electrophysiology (37% abnormal). Motor (34%) and sensory neurography (25%) were abnormal in HAVS. CTS frequency was not increased (9.4%).

CONCLUSION

Findings are consistent with a mechanically-induced, distally pronounced motor and sensory neuropathy independent of CTS.

SIGNIFICANCE

HAVS involves a neuropathy predominantly affecting large fibers with a sensory damage related to resonance frequencies of vibrating tools.