Tremor is a common complication of mercury poisoning, especially following industrial exposures. It may show a spectrum of severity, ranging from subclinical to totally disabling the patient.
Parameters:
(1) severity of the tremor
(2) difficulty with delicate motor function (writing, shaving, holding a glass, threading a needle)
(3) difficulty with gross motor function (walking, etc.)
Severity of Tremor |
Delicate Motor Function |
Gross Motor Function |
Grade |
none |
normal |
normal |
0 |
slight static tremor |
normal to slight |
normal |
I |
mild static with slight intentional tremor |
mild to moderate difficulty |
normal to slight difficulty |
II |
moderate static and intentional tremor |
conspicuous difficulties |
mild to moderate difficulty |
III |
severe |
totally disabled |
conspicuous difficulties |
IV |
generalized and intense (concussio mercurialis) |
totally disabled |
totally disabled |
V |
where:
• A slight static tremor may only be detectable with the arms outstretched with the fingers spread. The patient may be unaware of the movement.
Specialty: Toxicology, Emergency Medicine, Critical Care