Limits...
Quantitative analysis of tremors in welders.

Sanchez-Ramos J, Reimer D, Zesiewicz T, Sullivan K, Nausieda PA - Int J Environ Res Public Health (2011)

Bottom Line: Postural tremor intensity was increased in Welders and ET and was associated with visibly greater amplitude of tremor with arms extended.Mean center frequencies (Cf) of welders and patients with ET were significantly higher than the mean Cf of PD subjects.Although both the welders and the ET group exhibited a higher Cf with arms extended, welders could be distinguished from the ET subjects by a significantly lower Cf of the rest tremor than that measured in ET subjects.

View Article: PubMed Central - PubMed

Affiliation: College of Medicine, University of South Florida, Tampa, FL 33612, USA. jsramos@health.usf.edu

ABSTRACT

Background: Workers chronically exposed to manganese in welding fumes may develop an extra-pyramidal syndrome with postural and action tremors.

Objectives: To determine the utility of tremor analysis in distinguishing tremors among workers exposed to welding fumes, patients with Idiopathic Parkinson's Disease (IPD) and Essential Tremor (ET).

Methods: Retrospective study of recorded tremor in subjects from academic Movement Disorders Clinics and Welders. Quantitative tremor analysis was performed and associated with clinical status.

Results: Postural tremor intensity was increased in Welders and ET and was associated with visibly greater amplitude of tremor with arms extended. Mean center frequencies (Cf) of welders and patients with ET were significantly higher than the mean Cf of PD subjects. Although both the welders and the ET group exhibited a higher Cf with arms extended, welders could be distinguished from the ET subjects by a significantly lower Cf of the rest tremor than that measured in ET subjects.

Conclusions: In the context of an appropriate exposure history and neurological examination, tremor analysis may be useful in the diagnosis of manganese-related extra-pyramidal manifestations.

Show MeSH

Related in: MedlinePlus

Tremor Parameters in Healthy Controls. Left panel shows postural tremor intensity as a function of decade of life. Right panel shows Center frequencies of postural tremor against decade of life. Data are derived from accelerometer recordings of postural tremor using the Catsys Accelerometer system in 150 healthy controls (75 females and 75 males). Data were plotted from a published table of normal values [8].
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC3108121&req=5

f6-ijerph-08-01478: Tremor Parameters in Healthy Controls. Left panel shows postural tremor intensity as a function of decade of life. Right panel shows Center frequencies of postural tremor against decade of life. Data are derived from accelerometer recordings of postural tremor using the Catsys Accelerometer system in 150 healthy controls (75 females and 75 males). Data were plotted from a published table of normal values [8].

Mentions: Comparing tremor parameters of welders, IPD and ET subjects with published norms of healthy controls is instructive. In both the welders and the IPD group, the tremor intensity was significantly greater than in healthy controls measured with the same Catsys system. The mean intensity of postural tremor hovers between 0.11 and 0.13 throughout five decades of life (Figure 6). In contrast the postural tremor intensities of welders averaged 1.07 on the left and 1.61 on the right (a 12.4- and 9.7-fold increase, respectively, from healthy controls). Postural tremor intensities in the IPD subjects were also significantly elevated, up to 7.5-fold of healthy controls. In the ET group, the Cf increased with age. Interestingly, the Cf of postural tremor in controls declines normally with age, starting around 7.25 Hz in the 3rd and 4th decade of life and approximating 6.5 Hz by the 7th decade.


Quantitative analysis of tremors in welders.

Sanchez-Ramos J, Reimer D, Zesiewicz T, Sullivan K, Nausieda PA - Int J Environ Res Public Health (2011)

Tremor Parameters in Healthy Controls. Left panel shows postural tremor intensity as a function of decade of life. Right panel shows Center frequencies of postural tremor against decade of life. Data are derived from accelerometer recordings of postural tremor using the Catsys Accelerometer system in 150 healthy controls (75 females and 75 males). Data were plotted from a published table of normal values [8].
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3108121&req=5

f6-ijerph-08-01478: Tremor Parameters in Healthy Controls. Left panel shows postural tremor intensity as a function of decade of life. Right panel shows Center frequencies of postural tremor against decade of life. Data are derived from accelerometer recordings of postural tremor using the Catsys Accelerometer system in 150 healthy controls (75 females and 75 males). Data were plotted from a published table of normal values [8].
Mentions: Comparing tremor parameters of welders, IPD and ET subjects with published norms of healthy controls is instructive. In both the welders and the IPD group, the tremor intensity was significantly greater than in healthy controls measured with the same Catsys system. The mean intensity of postural tremor hovers between 0.11 and 0.13 throughout five decades of life (Figure 6). In contrast the postural tremor intensities of welders averaged 1.07 on the left and 1.61 on the right (a 12.4- and 9.7-fold increase, respectively, from healthy controls). Postural tremor intensities in the IPD subjects were also significantly elevated, up to 7.5-fold of healthy controls. In the ET group, the Cf increased with age. Interestingly, the Cf of postural tremor in controls declines normally with age, starting around 7.25 Hz in the 3rd and 4th decade of life and approximating 6.5 Hz by the 7th decade.

Bottom Line: Postural tremor intensity was increased in Welders and ET and was associated with visibly greater amplitude of tremor with arms extended.Mean center frequencies (Cf) of welders and patients with ET were significantly higher than the mean Cf of PD subjects.Although both the welders and the ET group exhibited a higher Cf with arms extended, welders could be distinguished from the ET subjects by a significantly lower Cf of the rest tremor than that measured in ET subjects.

View Article: PubMed Central - PubMed

Affiliation: College of Medicine, University of South Florida, Tampa, FL 33612, USA. jsramos@health.usf.edu

ABSTRACT

Background: Workers chronically exposed to manganese in welding fumes may develop an extra-pyramidal syndrome with postural and action tremors.

Objectives: To determine the utility of tremor analysis in distinguishing tremors among workers exposed to welding fumes, patients with Idiopathic Parkinson's Disease (IPD) and Essential Tremor (ET).

Methods: Retrospective study of recorded tremor in subjects from academic Movement Disorders Clinics and Welders. Quantitative tremor analysis was performed and associated with clinical status.

Results: Postural tremor intensity was increased in Welders and ET and was associated with visibly greater amplitude of tremor with arms extended. Mean center frequencies (Cf) of welders and patients with ET were significantly higher than the mean Cf of PD subjects. Although both the welders and the ET group exhibited a higher Cf with arms extended, welders could be distinguished from the ET subjects by a significantly lower Cf of the rest tremor than that measured in ET subjects.

Conclusions: In the context of an appropriate exposure history and neurological examination, tremor analysis may be useful in the diagnosis of manganese-related extra-pyramidal manifestations.

Show MeSH
Related in: MedlinePlus