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Geoffrey Walsh
12-05-1997, 11:57 PM
Some years ago with colleauges I was investigating and measuring muscle
tone in normal subjects, patients with Parkinsonism, strokes etc. We were
using specially devised apparatus.

The methods are described in summary form in my book

Muscles, Masses and Motion
The Physiology of Normality, Hypotonicity, Spasticity and Rigidity
Clinics in developmental Medicine 125.
MacKeith/Cambridge University Press
ISBN 0 521 43229 4

We found that under certain circumstances the stiffness recorded depended
on the past history of movement i.e. there was a 'memmory' of what had
happened. If the limb had been still it was measureably stiifer than if it
had been moving in the immediate past. Our group has had a number of
publications about his effect. I list some of them below -


Lakie M., Walsh E. G. & Wright G. W. (1980) 'Passive wrist movements - a
large thixotropic effect.' Journal of Physiology, 300, 36-37 P

Lakie M., Walsh E. G., & Wright G.W. (1980) 'Thixotropy - a general
property of the postural system.' Journal of Physiology, 305, 73-74P.

Lakie M., Walsh E. G. & Wright G. W. (1981) 'Sudden increase of wrist
stiffness for small movements - demonstrated by positive velocity
feedback.' Journal of Physiology, 312, 46-47P.

Lakie M., Walsh E. G. & Wright G.W.(1983) 'Cooling of the forearm -
changes in thixotropy.' Journal of Physiology, 343, 112-113P.

Lakie M., Walsh E. G. & Wright G. W. (1984) 'Passive wrist movements -
thixotropy - measurement of memory time.' Journal of Physiology, 346, 6P.

Lakie M., Walsh E. G. & Wright G. W. (1984) 'Resonance at the wrist
demonstrated by the use of a torque motor: an instrumental analysis of
muscle tone in man.' Journal of Physiology, 353, 265-285.

Lakie M., Walsh E. G. & Wright G. W. (1986) 'Control and postural
thixotropy of the forearm muscles; changes caused by cold.' Journal of
Neurology, Neurosurgery and Psychiatry, 49, 69-76.

Walsh E. G. & Wright G. W. (1988) 'Postural thixotropy at the human hip.'
Quarterly Journal of Experimental Physiology, 73, 369-377.

Walsh E. G. (1992) 'Postural thixotropy - a significant factor in the
stiffness of paralysed limbs ?' Paraplegia, 30,113-115.

Lakie & Robson (1988) Thixotropy: the effect of stretch size in relaxed
frog muscle Quarterly Journal of Experimental Physiology 73, 127 - 129

Lakie & Robson (1988) Thixotropic changes in human muscle stiffness and
the effects of fatigue in frog muscle Quarterly Journal of Experimental
Physiology 73, 487-500

Lakie & Robson (1988) Thixotropy: the effect of stimulation in frog
muscle. Quarterly Journal of Experimental Physiology 73, 627-630

Lakie & Robson (1990) Thixotropy in frog single muscle fibresQuarterly
Journal of Experimental Physiology 75, 123-125

I am aware that Dr. Alan Weigner in Boston (USA) has made some
measurements along these lines in relationship to malignant hyperpyrexia
but I am now wondering if there has been other work on these effects
elsewhere.

As the phenomena are often so clear in normal subjects it is to be
expected that in some pahological conditions there may be more or less
thixotropy or different memmory times .

Beneficial effects of physiotherapy may result in part from changes in
thixotropy induced by the p[roceedures.

Does anyone have any relevant information ?


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Email - Geoffrey.Walsh@ed.ac.uk
http://www.ed.ac.uk/~gwalsh
Phone 0131.664.3046
64, Liberton Drive,
Edinburgh
EH16 6NW