Focal primary dystonia (FPD) has been recognized
as a motor disorder, although clinical, neurophysiological
and imaging observations suggest that sensory dysfunction
might also be involved.1-4
Underlying mechanisms that involve frequent, repetitive
and temporarily related stimuli could be a factor
triggering focal dystonia. It has been shown that the
sensory cortex (S1) and secondary parietal cortex
record increased activity during dystonic posture.5 Some
studies have found that, in patients with focal hand
there is an abnormal representation in S1 and that
this abnormality may be related to the severity of the
5 In these patients, there may be a loss of the cortical
inhibition, and an increase in neuronal plasticity.6
We report two patients with writer’s cramp dystonia who
responded well to prolonged and repeated stimulation of
their hand muscles with acupuncture needles.
Sixty-year-old, right-handed male patient, writer
by profession, with a right writer’s cramp dystonia that
started four years earlier. One year before he had been
administered a treatment with botulinum toxin, which
improved the dystonia for six months.
We performed a muscle puncture in his right hand
using acupuncture needles in the abductor pollicis brevis
and first interosseus dorsalis muscles for 30 minutes.
After this procedure, the patient showed significant
improvement in his writing for more than 72 hours. The
procedure was repeated twice a week for a
month and then once a week. The patient has shown a
significant improvement until one year after of the
Seventy-two-year-old, right-handed male
patient, lawyer, with a writer’s cramp dystonia that
started five years earlier. He has been working as a
writer for 30 years. He had not been able to write for one
year before treatment (Figure 1a). We performed a muscle
puncture in his right hand using acupuncture needles
in the abductor pollicis brevis and first interosseus
dorsalis muscles for 30 minutes. Immediately after the first
muscle puncture the patient was able to write again
with mild difficulty (Figure 1b). The procedure was
repeated twice a week for a month and then once a month for
The patient has been able to return to his
previous work as a writer. The patient has continued
working until one year after of the first stimulation with
acupuncture needles (Figure 1c). The patient did not take any
medication for dystonia during treatment.
Our results show that writer’s cramp
dystonia may improve with deep repeated muscle
stimulation in the abductor pollicis brevis and first interosseus
dorsalis, with the consequent mitigation of its severity
and persistence over time.7
evident motor manifestation of idiopathic focal hand dystonia, it has been
recognized that the sensory system performs an
important role in this condition.1,2,3,4,8
There is much
evidence substantiating sensory dysfunction in patients with
dystonia: sensory symptoms may precede the appearance of
dystonia; certain sensory tricks used by patients may
help to relieve dystonic postures and sensory training such
as the one used for Braille reading3
peripheral blockage may relieve the dystonic posture of the hand.9,10
Sensory dysfunction may contribute to a loss of
sensory-motor integration and abnormality of the motor
output in focal dystonia.1,5,11
The sensory system is a major drive for the
motor system and the basal ganglia perform an
important role in the central processing of the somato-sensory
drive.4,5,11. The temporal discrimination, a function of
the basal ganglia, and the spatial discrimination, a function
of S1, are impaired in dystonia
The sensory dysfunction, however, if not the
primary event in dystonia, may certainly contribute
to impaired sensorimotor integration and abnormal motor
In patients with focal hand dystonia,
various abnormalities have been shown at different levels of
experiments with animals, sensory studies with highly repetitive stimuli induce an
abnormal process of sensory information and a
remodeling of the
neuronal plasticity of the primary somato-sensory cortex.
13 Imaging studies of patients with writer’s cramp indicate
an increased output from the basal ganglia to the
thalamus and the cortical areas, with an upregulation of
the pre-motor and motor cortex with co-contraction and
dystonic posture.14 Studies with fMRI in patients with focal
hand dystonia have shown an abnormality in the cortical
representation of individual digital in the primary
somato-sensory cortex. In these patients, the cortical
of the fingers of the hand is compressed and
disorderly. Increase and overlay of the receptive fields
have been found, as well as an occasional inversion of
the digital representation8 and a loss of the cortical
function, probably with fluctuation in the activity
of inter-neurons in S1 and M1.6 The hypersensitivity and
expansion of the cortical sensory-motor representation
corroborates the hypothesis that dystonia is a sensory
disorder produced by an environmental experience.1,4
Neurophysiological research has revealed cortical
in patients with focal dystonia that reflect an underlying
Our results suggest that prolonged and repeated stimulation
of certain muscles of the hand related to writer’s
cramp produce a favorable therapeutic response that persists
over time, this contributes to demonstrating the sensory
participation of dystonia but also shows that intense
peripheral sensory input could achieve modification of
the cortical sensory-motor response.
We do not know about the neurophysiological mechanisms
whereby intense and prolonged stimulation of
the muscle is capable of producing a therapeutic response
that persists over time. It is probably due to a
related to neuronal plasticity of the cortical
Our findings open up new avenues of physiopathological
and therapeutic research.
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