Therapeutic riding in patients affected by progressive and non progressive torsion dystonia: a preliminary report

A SPECIFIC THERAPEUTIC RIDING INDICATION:
TORSION DYSTONIA
Prof. ANNA PASQUINELLI*, Dr. PAOLA ALLORI*, Ph MEIKE SUSANN
RAUPACH°, Dr. ETTORE CATERINO*
* Child Neuropsychiatrists, Institute of Child Neuropsychiatry, Department of Neurological and Psychiatric Science, University of Florence ° Physiotherapist, TR Instructor, TR Center "La Querce" Montemurlo (Prato).
Torsion Dystonia (TD) as the progressive form (PTD) as the non progressive one (NPTD), represents one of the most disabling Extrapyramidal Disorders (ED), and one of the least responsive to the various treatment (physiotherapeutic and pharmacological). The Postural Pattern (PP) characteristic of both forms is that of asymmetrical opisthotonus, extreme as regards position and muscolar involvement, accentuated by any stimulus or motor initiative. On the basis of this pattern there persists a general axial and limbs attitude with segmentary inconsistency of the rotational type (the vectorial inconsistency of rotation in the various segments constitutes the "torsion"). A "tonic innervation", often maximal and not reducible by agonists and antagonists, characterizes the TD postural and motor patterns. Particularly in the progressive form the affected limb or limbs assume a permanent abnormal posture with superimposed fluctuations. All of this results in alterations in breathing, swallowing, phonation, muscular hypertrophy (e.g. neck, shoulders), deformity (scoliosis, inverted foot), etc. Periods of spasm occur in crescendo, the intervals between them becoming progressively shorter, eventually occupying both day and night even for very long periods. Physiotherapeutic and pharmacological TD treatment (dopamine agonist and antagonists, anticolinergics, benzodiazepins, baclofen, etc) is generally disappointing No specific report about the application of TR on generalized TD are found in the literature, except for a previous notation of ours (Pasquinelli et al, 1997), or some results on focal dystonia (spasmodic torticollis). The purpose of this study is to analize the effect of TR treatment in S affected by pure TD in order to identify the most responsive symptoms. This is because, given the extreme rarity of the
pure form of TD and instead the frequency of its typical postural patterns such as torsion,
opisthotonus, segmentary inconsistency, in the mixed forms, we believe it will be extremely useful:
1 - to find a rehabilitation technique able to inhibit these highly disabling and dominant patters, and
thus to allow the emerging of more positive functional patterns, which are otherwise occluded
("tyranny of the pattern": "Milani Comparetti's diadikasia", 1971)
2)- not to contraindicate TR for S presenting these symptoms, as might be thought proper upon
superficial evaluation, considering that, as will be seen, TR can instead prove itself to be the
elective indication.
We present results relevant to S affected exclusively by pure forms TD which are very severe, but
different in etiopathogenesis, age, therapeutic treatment and follow up, in order to demonstrate that
the results obtained are "symptom-dependent", that is, any positive response is independent of said
variables and thus applicable to any subject presenting these symptoms: it is the symptom which
responds, not the form.
Further studies on homogeneous cases can furnish information on the response characteristics of the
individual forms.
PRELIMINARY REMARKS
This study is part of the research program on the methodology and the objective assessment of TR on ED being carried out, since 1993, by the Institute of Child Neurology and Psychiatry of the University of Florence in collaboration with Tuscan TR Centers. The medical team is made up of Child Neuropsychiatrists (CNP) from the Institute, who are responsible for setting up the TR program, including its methodology. They also act as scientific consultants for the TR Centers, and lastly, process the results. The TR Center's Team consists of a Riding Instructor, a Physiotherapist, Professional Educators, each of them are specialized in TR, Volunteers and the CNP. SUBJECTS
All the S are followed by our Institute in collaboration with two TR Centers: "Elisa" Center in
Florence and "La Querce" Center in Montemurlo (Prato).
4 male S, 2S affected by progressive generalized TD: GF: Idiopathic (or Primary) Dystonia; RL:
Infantile Bilateral Striatal Necrosis (IBSN) probably due to mitochondrial encephalopathy and 2S
(TV, ZJ) by non progressive TD ("Secondary" Dystonia) due to perinatal cerebral injury:
Dyskinetic Cerebral Palsy (Hagberg, 1984): "pure TD", according to Papini et al Classification of
Extrapyramidal Cerebral Palsy (1990).
Age at the beginning of TR: mean 9y5m, range: 3y–14y3m (GF 11y2m, RL 14y3m ;TV 3y; ZJ:
9y4m)
TR follow up: 3S: ongoing treatment: range 4m-3y (GF: 4m; TV: 1y; ZJ: 3y); 1S (LR): 11 cycles
for 9y (2 cycles each year the first 2ys and then 1 each year for the other 7 ys).
1S (ZJ) presented marked microcephaly and hyposomatism.
Disability level, according to the "Gross Motor Function Classification System" (GMFCS)
(reviewed by Palisano et al, 1997) was severe in 3/4S: 5th Level (no or poor head control) in 2S
(TV,ZJ); 4th Level (unable to walk) in 1S (RL); 2nd Level (walking with difficulty) in 1S (GF).
Mental Retardation was present in 3S (RL TV ZJ) (mild in RL, severe in TV, profound in ZJ).
Psychiatric involvement: absent.
Epilepsy: 1S (ZJ), in good control.
Neuroimaging: in the progressive forms: GF: negative; RL: olotopistic striatal degeneration; in the
non progressive forms: TV: periventricular leukomalacia, ZJ severe encephalic atrophy.
Involuntary Movements (IM) was present in 3S: grimaces 3S, choreoatetoid/ballic movements 2S,
flail movements: 1S (ZJ)
All the S had severe torsion and stiffness and the other pathological patterns characteristic of TD.
In all of the S the TD was present in structured form with worsening linked to motor initiative,
emotional state, fatigue and concomitant internal problems (respiratory, gastro-enteric problems,
infections in general, osteo-articolar, orthopedic problems, especially when associated with painful
symptomatology). Considering the severity of the symptomatology and its effect on functional and
adaptational competences, all of the S included in the study were on antidystonic treatment.
METHODOLOGY
The TR programme and evaluation of the results has been carried out in collaboration between the
Neuropsychiatrists from the Child Neuropsychiatry Institute and the TR Centres Team to set up an
integrated rehabilitation programme.
TR is applied twice a week in the 3 local resident S: ongoing treatment. In 1 S (RL), an out-of-town
S, TR is carried out in cycles consisting of 8 lessons for 1 month (twice a year in the first 2 years,
once a year in the others 7ys) during the hospitalization.
Lesson method: the TR lesson lasts 50 minutes.
In view of the severity of the pathology the TR began with HPP; the lessons were individual or,
later, in group. An english riding saddle with a special handle, which serves to maintain an adequate
trunk posture with open shoulders ("ELISA" saddle) (Gentile, 1997), was used. In the 2S less
severely affected (GF LR) it was sometimes possible to utilize riding reins and to move on to ER. In
the most severely affected S (ZJ), therapy was started without the saddle with the backrider and
only after 2 years was it possible to use the saddle.
TR Assessment
Serial Videorecordins (VRs) and obsevation both on horseback and on the ground are made and
analyzed at established intervals (0-3-6-12-24-36-48-60 months) or at the beginning and the end of
the cycles, according to our Scale "TR ED Assessment Scale" (Pasquinelli et al, Denver, 1997, reviewed). The VRs are then analyzed at slow motion and still playback to assess the results. The effects of TR on target symptoms (above all torsion, opisthotonus, stiffness, segmentary inconsistency, IM), functional competences, adjustment of tone, strength and timing are scored. RESULTS OF THE INDIVIDUAL CASES
(this part probably will not be read; thus GO DIRECTLY TO OVERALL RESULTS on
page 6 and to the next pages up to the end)
PROGRESSIVE FORMS: 2 S (GF,LR)
GF: ongoing treatment, age at TR beginning 11y2m; TR follow up: 4m; TR suspended
LR: 11 cycles of 8 lessons for 1 month for each cycle; age at TR beginning 14y3m; TR follow up:
9y; the TR cycles are still continuing. This represents the 1st patient affected by TD to undergo TR
treatment in 1993.
ON HORSEBACK
We observed right from the very first lesson a marked and impressive gap between the neuromotor conditions on the ground (extremely severe) and those on horseback: excellent/good control of pathological patterns such as torsion and segmentary inconsistency (LR/GF), and of IM (that completely disappeared with the horse movement), flexion (good control) (GF); good improvement of stiffness and of adjustment of tone; mild improvement of adjustment of strength and timing. Later on (GF 3rd months; RL at the end of the cycle) good improvement of strength and timing, and consequently of latency, good improvement in motor planning and coordination, mild improvement of balance reactions. Excellent improvement of flexion (GF). Striking and unexpected – this was the 1st patient on TR – was the dramatic reduction in torsion, which was due to the horseback posture alone, with the immediate acquisition of a more symmetric axial posture. The horse's movement then leads to a further improvement of this pathological pattern and of the others dystonic symptoms. The "TR ED Assessment Scale" examines:
a) neuromotor modifications observed on horseback and long-term ones on the ground;
b) possible modifications immediately following the TR session (within 20
minutes).This item serves to assess the difference in neuromotor capacity between the time just before mounting the horse and right after (within 20 minutes) c) acquired riding skills  the score is named according the "TR ED Assessment Scale": negative= worsening; none= unchanged; mild: difference of 1 point; good: difference of 2 points; excellent: difference of 3 points; dramatic: difference of 4 points The acquired control of pathological patterns and IM, the marked reduction of hypertone (stiffness)
and its regolarisation, result in the acquisition and maintaining of more correct postures. The better
coordination of motor acts and independence of the various body districts from each other, make it
possible to perform more appropriate complex stochastic motor acts with acquisition of some riding
competences.
TR TIME ON HORSEBACK: 0-3m

RIDING SKILLS
Because of the neurological severity both of the S began with HPP at the lower level: 2nd level: LR A2B1 , GF A2B2: S rides horse at slow walk using the "Elisa" saddle and holding a special handle, with leader holding horse on the longe and the TR Instructor aside. Because of their good mental level and the maintainance of the excellent results achieved on horseback they were able to move on to higher HPP Levels and at times even to the Remedial Education Riding (ER) program (occasionally, although not always, for brief periods): GF could ride holding reins with fair ability and perform exercises at slow walk, ER 2nd Level B2C1, because of improvement of motor planning and coordination; while holding the handle he could ride at sitting trot: HPP 3rd Level A3B3C2D1. LR (in the first 6 year) could ride holding reins with fair ability at slow walk: ER 2nd Level A3B2, or in HPP program to trot (sitting trot) at 3rd Level A3B3C2D1; after 6y, because of the progressive worsening of the disease, he came back to HPP 3rd level A2B2 (slow walk). ASSESSMENT OF NEUROMOTOR COMPETENCES ON THE GROUND AT THE
BEGINNING AND RIGHT AFTER THE END OF THE LESSON (within 20 minutes)
We could notice some positive results in the less severely affected child, GF: after 3m, the steady consolidation acquired on horseback of a marked reduction in torsion, flexion and segmentary inconsistency, as well as the improvement of the consensus mechanisms and motor planning and coordination resulted in an improved upright position (standing), greater nimbleness and coordination in walking and improved control of IM. In the other more severely affected child(unable to walk), LR, he maintained only a mild adjustment of tone and reduction of stiffness, but he reported a subjective sensation of greater relaxation and less tiredness. ASSESSMENT OF THE NEUROMOTOR COMPETENCES ON THE GROUND

In spite of the shortness of the follow up (GF= 4m) and of the cycles (1 month each cycle) we
observed the maintaining on the ground of a mild positive effect on the adjustment of tone and
stiffness in both the S (GF,LR) and on latency, flexion, torsion, foot avoiding in GF, with a
consequent mild improvement in standing, walking and utilisation of upper limbs. In spite of the
results obtained GF, after having interrupted TR during the summer holidays, has not resumed this
activity.
In LR these results were transitory because of the shortness and the rare frequency of the cicles and
primarly, due to the worsening of the disease. However we observed the same positive differences
between the beginning and the end of each cycle regardless of the situation at the start.
TR TIME ON GROUND: 1m-3m
NON PROGRESSIVE FORMS: 2 S (TV,ZJ)
 in HPP A= stationary; B= slow walk, C=fast walk; D: trot; 1=poor ability, 2= fair ability, 3= good ability ,4= excellent ability TV: ongoing treatment, TR beginning: 3y; TR follow up: 1y; transferred to another health-care
Center.
ZJ: ongoing treatment TR beginning: 8y7m; TR follow up: 3ys, TR in progress.
These S are very severely affected: no or poor head control (disability level: 5), severe/profound
mental retardation.
ON HORSEBACK
In the face of their disability we could observed marked improvement in these S, too.
During the follow-up we observed:
- right from the very first lesson in both the S, an excellent/good control of torsion and
opisthotonus (ZJ/TV)and IM (disappeared); a good/mild improvement in segmentary inconsistency
(TV/ZJ), mild improvement in tone and stiffness; strength and timing improved only in TV. Startle
disappeared in TV and improved mildly in ZJ (score on the ground 4= severe).
TV: avoiding: good; ZJ: grasping: mild.
- after 6 months: further improvement in tone with reduction of stiffness, torsion and opisthotonus
with acquisition of a more symmetric posture on horseback in the less severely affected S; further
reduction of startle in ZJ (score: 2)
- after 1 year: mild improvement of strength in TV; further improvement of tone, stiffness, torsion,
opisthotonus, startle in ZJ (score: 1); in TV disappearance of segmentary inconsistency
- after 2y (ZJ): the consolidation of the extremely positive results as regards control of
pathological patterns (disappearance of torsion, opisthotonus, startle), the excellent results on
stiffness, ** the improvement in strength (at 2y) made it possible to use the saddle with the stirrups
and to trot for brief periods, the almost complete control of startle made it possible to move from
individual to group lessons.
** good: flexion, segmentary inconsistency, grasping
TR TIME ON HORSEBACK: 0-2y

RIDING SKILLS

Because of neuropsychic severity, both the S began with HPP and remained in this module.
TV could achieve the 2nd level (with the saddle, without the backrider, but holding the handle) at
slow walk with fair ability: A2B2.
ZJ began at the 1st level A1B1 at slow walk without the saddle in an individual lesson because of
the neurological severity and due to the frequent and low threshold startle which could have
triggered the extensory pattern. The 1st, long = 2y (duration =2ys), phase consisted mainly of
working to inhibit the extragravitary pattern, e.g. opistothonus, torsion and startle, in favour of
flexory pattern and of a more symmetric posture; then at the 2nd year the maintaining of good
inhibition of the invalidating patterns, the reduction in stiffness, improvement in strength and
righting mechanisms of head and trunk, made it possible to move on to group lessons, to use the
saddle and even to trot for brief periods (1st Level A3B3C2D1).
ASSESSMENT OF NEUROMOTOR COMPETENCES ON THE GROUND AT THE
BEGINNING AND RIGHT AFTER THE END OF THE LESSON (within 20 minutes)

Due to the severity of disability – Level 5th – in both the S no significant modification occurs
except for a mild reduction of hyperthonus
ASSESSMENT OF THE NEUROMOTOR COMPETENCES ON THE GROUND
In spite of the severity of the clinical picture we observed a gradual (TV 6m-1y; ZJ: 1y- 2y) mild
improvement in torsion, opistothonus, segmentary inconsistency, startle(2y in ZJ), stiffness (1y in
ZJ).
TR TIME ON THE GROUND: 6m-2y

OVERALL RESULTS
ON HORSEBACK

RIGHT FROM THE VERY FIRST LESSON we observed a marked and impressive gap
between the neuromotor conditions on the ground (extremely severe) and those on horseback: the
horseback posture alone dramatically inhibits dystonic postural pattern which is further reduced by the horse's
movement.
Control of Pathological PP and MP:
Torsion: excellent* in 2S (beginning at a score of 4 ); good in 3S (beginning at a score of 3);
Opisthotonus: Excellent (ZJ)/good (TV) in 2/2S (NPTD),
Segmentary inconsistency: excellent/good in 2S (LR/GF) (PTD), mild in 2S (NPTD);
Flexion: good in 1S (GF); apparently worsening in ZJ: the dramatically reduction and control of
Torsion and Opisthotonus resulted in this S in the emergence of a flexory pattern but combined with
the great aposturality, that is occluded by those tyrannic hyperestensory patterns;
Startle: disappearance in 2S (GF, TV, mild in 1/3S (ZJ),
IM: excellent in 3/3S. The complete control (disappearance) was achieved on horseback (walk-
trot)(horse in motion) while there was less control when the horse was stationary.
Adjustment of consensus mechanisms impaired in all the S: tone: good improvement in 2S
(PTD), mild in 2S (NPTD); adjustment of strength: good 1s (LR), mild in 1S (TV); mild adjustment
of timing: 3/4
AT THE AND OF FOLLOW UP we observed a further improvement of:
Control of Pathological PP and MP:excellent in all the S:
Torsion (4/4S), Opisthotonus (2/2), Startle (3/3): disappeared
Flexion: excellent 1/2S;
Segmentary inconsistency: excellent in 3S, good in 1S (ZJ)
Grasping/Avoiding: disappear in 1S (GF), good in 3S
Stiffness: excellent in 3S (beginning at a score of 4), good in 1S(GF) (beginning at a score of 3)
Latency: excellent in 1S (GF), mild in 2S (LR, ZJ)
IM: disappeared
Adjustment of: tone: good in 4S; strength: good in 3/4S, mild in 1S (ZJ); timing: good in 2/4 S;
mild in 1S TV, no improvement in 1S (ZJ)
Motor Planning and coordination: excellent/good 2/2S (impossible evaluation in the 2S more
severely affected
Balance improvement: mild in 2S (PDT)
TR TIME ON HORSEBACK: 0-2 years

RIDING SKILLS
* the score is named according the "TR ED Assessment Scale": negative= negative= worsening; none= unchanged; mild: difference of 1 point; good: difference of 2 points; excellent: difference of 3 points; dramatic: difference of 4 points ° Evaluation of Target Symptoms: 0= absent, 1= mild; 2= moderate; 3= strong; 4= severe
Because of the neurological severity all the S began with HPP but the most severely affected
remained in this module and the other 2 move on to ER (they could ride holding reins and in HPP
program could trot). However also the 2S affected by Non Progressive TD with a disability level of
5, could improve their competences on horseback (the S with a more extended TR treatment could
trot). In detail:
S affected by NPDT:
TV could achieve the 2nd level (with the saddle, without the backrider, but holding the handle) at
slow walk with fair ability: A2B2.
ZJ began at the 1st level A1B1 at slow walk without the saddle in an individual lesson because of
the neurological severity and due to the frequent and low threshold startle which could have
triggered the extensory pattern. The 1st, long = 2y (duration =2ys), phase consisted mainly of
working to inhibit the extragravitary pattern, e.g. opistothonus, torsion and startle, in favour of
flexory pattern and of a more symmetric posture; then at the 2nd year the maintaining of good
inhibition of the invalidating patterns, the reduction in stiffness, improvement in strength and
righting mechanisms of head and trunk, made it possible to move on to group lessons, to use the
saddle and even to trot for brief periods (1st Level A3B3C2D1).
The S affected by PTD began in HPP at a low level: 2nd level: LR A2B1 , GF A2B2: S rides
horse at slow walk using the "Elisa" saddle and holding a special handle, with leader holding horse
on the longe and the TR Instructor aside.
Because of their good mental level and the maintainance of the excellent results achieved on
horseback they were able to move on to higher HPP Levels and at times even to the ER program
(occasionally, although not always, for brief periods): GF could ride holding reins with fair ability
and perform exercises at slow walk, ER 2nd Level B2C1, because of improvement of motor
planning and coordination; while holding the handle he could ride at sitting trot: HPP 3rd Level
A3B3C2D1.
LR (in the first 6 year) could ride holding reins with fair ability at slow walk: ER 2nd Level A3B2,
or in HPP program to trot (sitting trot) at 3rd Level A3B3C2D1; after 6y, because of the progressive
worsening of the disease, he came back to HPP 3rd level A2B2 (slow walk).
ASSESSMENT OF NEUROMOTOR COMPETENCES ON THE GROUND AT THE
BEGINNING AND RIGHT AFTER THE END OF THE LESSON (within 20 minutes)
We could notice some positive results in PTD and particularly in the less severely affected child, GF: after 3m, the acquired consolidation on horseback of a marked reduction in torsion, flexion, and segmentary inconsistency, as well as improvement in consensus mechanisms and motor planning and coordination resulted in an improved upright position (standing), greater nimbleness and coordination in walking and improved control of IM. In the other more severely affected child, LR, (unable to walk) he reported only a mild adjustment of tone and a subjective sensation of greater relaxation and less tiredness. In the 2 more severly affected S (NPTD) - Level of disability 5 no significant modification occurs except for a mild reduction of hyperthonus. ASSESSMENT OF THE NEUROMOTOR COMPETENCES ON THE GROUND
In spite of the shortness of the follow up and of the cycles for the 2S affected by the progressive form, and the severity of the clinical picture for the other 2S, we observed a mild improvement of stiffness in all the S, of torsion in the 3S on ongoing treatment (GF,TV, ZJ), of startle, segmentary inconsistency and opisthotonus in 2S (NPTD).  in HPP A= stationary; B= slow walk, C=fast walk; D: trot; 1=poor ability, 2= fair ability, 3= good ability ,4= excellent ability In the less severely affected S (GF) the positive effect on consensus mechanisms, motor
programming and coordination, latency, flexion, foot avoiding, resulted in a mild improvement of
antigravitational competences (standing, walking) and in the utilisation of upper limbs.
In LR the excellent results obtained on horseback are not maintained on the ground because of the
shortness and the rare frequency of the cycles and the worsening of the disease, too. However we
observed the same mild positive effect on stiffness between the beginning and the end of each cycle
independently from the starting situation.
TR TIME ON THE GROUND: 4m - 2y

DISCUSSION and CONCLUSION

In all the S regardless of etiopathogenesis, age, level of neuromotor impairment and mental
retardation, we observed right from the very first lesson that the horseback posture alone
dramatically inhibits IM and dystonic postural patterns e.g. torsion, opisthotonus, segmentary
inconsistency, which are further reduced by the horse's movement with the prompt
acquisition of a more functional posture: "Responsiveness of the Symptom" to TR.
The more gradual (0-2ys) but always excellent/good improvement in control of saboteur motor
patterns such as startle (disappearance), in adjustment of consensus mechanisms, such as tone and
timing with consequent reduction in stiffness and latency, in stabilization of the control of
pathological Patterns made it possible to achieve riding competences, even in the most severely
affected child (use of the saddle, trotting). In the 2 less severely affected S (PTD) and with a good
mental level, the acquisition of better coordination of motor acts and independence of the various
body districts from each other, made it possible to perform more appropriate complex stochastic
motor acts and to move on to a higher level of HPP and then to Remedial Education Riding, with
the capacity to ride holding the reins, to perform exercises on horseback and to trot.
HOW CAN THESE STRIKING RESULTS BE EXPLAINED?

From a neurophysiological point of view we must stress the particular relationship between the
Extrapyramidal System and the sensitive/sensorial afferent pathways and the marked
interdependence between dystonia and sensitive/sensorial system (Halley 1995,1997).
It is known that:
- in dystonic S the assumed posture is highly dependent on the position of the body in space (vestibular afferences) and on body contacts (tactile and proprioceptive afferences) (Denny-Brown, 1962); - the IM, stiffness, dystonic attitude are inhibited by sensitive stimuli (tactile, proprioceptive) e.g. "sensory tricks"; - freezing and apraxia in walking are reduced by rhythmical stimuli. Papini et al, (1993) pointed out as in TD, the torsion pattern can be inhibited by maintaining a forced flexory position with hyperflexion of the hips ("basket position") associated with a rhythmic stimulation ("rocking horse"). 1) On horseback the S is subjected to continuous and important vestibular, tactile and
proprioceptive stimulations both stationary and above all with the horse's rhytmic movement.
2) "the horseback posture" is a functional posture in itself, because of the broad plane of support,
which determines dramatic inhibition of the hyperextensory patterns (opisthotonus and torsion) for
a more functional antigravitary posture. In the most severe form it often causes the subject to fall
into the flexion posture, as in our 2 S affected by severe Non Progressive TD.
In this form of Cerebral Palsy (NPDT), the lack of the neurophysiological antigravitary
prerequisites due to the brainstem tyranny, produces only two dominant alternating patterns,
hyperextensory/flexory patterns. Consequently, the control of the first pattern, achieved on
horseback, causes the S to fall into the second one. But it represents a more functional posture
which can allow the emergence of trunk righting mechanisms (depending on the severity of the
form), thanks to the afferences, especially proprioceptive, enhanced by the horse's movement.
Instead if the neurophysiological prerequisites for the antigravitary competence are available, as in
our S affected by Progressive TD, (S with previous normal neuromotor development and less
severely affected), a prompt and evident results with acquisition of a posture that is almost correct
from a functional viewpoint, is realized. This is probably due to the fact that hyperestensory
patterns occludes patterns previously normal. Thus their control allows the re-emerging of
antigravitary patterns, achieved and maintained on horseback due to the posture assumed and the
constancy of the symmetrical, afferent stimuli enhanced by the horse's rhythmic movement, but
retained only partially on the ground due to the absence of these facilitating factors.
The use of the saddle can furnish much better holding of the posture.
Both these 2 points, e.g. the "horseback posture" and the constancy of afferent stimuli, can
explain the striking results observed right from the first lesson on horseback.
Further studies on homogeneous groups of patients are necessary to determine the responsiveness of
the different TD forms, (progressive and non progressive, pure and mixed ones) and the definition
of maintaining effects on the ground, which is the real target of any rehabilitation treatment.
However the steady responsiveness of dystonic postural patterns e.g. torsion, opisthotonus, segmentary
inconsistency, in such severe and pure forms of TD as in our S, prove that TR should be considered a specific
indication for these symptoms in any clinical picture and could represent, in combination with
pharmacological treatment, a real possibility of rehabilitation available to S in which only forced,
abnormal and non-functional postures are possible.

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