Relationship between work fatigue and manual dexterity in dental professionals: observational study.

BACKGROUND: Neuro-muscular fatigue (ANM) in the upper limbs can cause impaired coordination and dexterity. The main purpose of the study was to investigate whether ANM induced by a working day produced a reduction in digital dexterity in a population of dental health workers (OSD). Secondary objective was to investigate whether there were relationships between any reductions in dexterity and independent socio-demographic variables (gender, age and profession). METHODS: A cohort of OSD was assessed before and at the end of a working day of at least 7 hours using the Functional Dexterity Test (FDT). The effects of ANM (time), of the tested limb (dominance), and of their interaction on dexterity were investigated using two-way ANOVA. A multiple linear regression model was applied to explore the relationship between dexterity performance and independent variables. RESULTS: A total of 50 OSDs were included. The net time of the FDT at the end of the day was always higher than in the morning. The ANOVA showed a significant difference for time (p <0.001) and side (p <0.001), but an effect from the interaction between the two factors was not identified (p = 0.428). The worsening of manual dexterity appears to be weakly correlated with age on both sides, and with the profession in the dominant limb. CONCLUSION: The ANM appears to have negatively affected the dexterity of both hands in the sample examined. The results of this study may be useful for planning the OSD's work agenda more carefully.

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, CI95% 0.83-0.99; LR+: 14.49, CI95% 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.