Importância do Papel dos Pacientes na Educação Médica

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extremely useful, as it is not uncommon for patients and their
families to become the best teachers of the providers who
return their care.
ACKNOWLEDGEMENTS
The author’s work on Lesch–Nyhan disease is supported in part by
grants from the NIH (HD053312, DK82840, and NS067501).
REFERENCES
1. McCarthy GT, Green EM, Ogunbona O, et al. A population
study of Lesch–Nyhan disease in the United Kingdom. Dev
Med Child Neurol 2011; 53: 34–9. DOI: 10.1111/j.1469-
8749.2010.03786.x.
2. Jinnah HA, Ceballos-Picot I, Torres RJ, et al. Attenuated
variants of Lesch–Nyhan disease. Brain 2010; 133: 671–89.
3. Jinnah HA, Visser JE, Harris JC, et al. Delineation of the
motor disorder of Lesch–Nyhan disease. Brain 2006; 129:
1201–17.
4. Puig JG, Torres RJ, Mateos FA, et al. The spectrum of
hypoxanthine-guanine phosphoribosyltransferase deficiency:
clinical experience based on 22 patients from 18 Spanish fam-
ilies. Medicine 2001; 80: 102–12.
5. Jinnah HA, De Gregorio L, Harris JC, Nyhan WL, O’Neill
JP. The spectrum of inherited mutations causing HPRT
deficiency: 75 new cases and a review of 196 previously
reported cases. Mutat Res 2000; 463: 309–26.
The contribution of spasticity to the movement disorder of cerebral
palsy using pathway analysis: does spasticity matter?
JEAN-PIERRE LIN
Guy's & St Thomas' Hospitals Foundation Trust, Paediatric Neurology, London, UK.
doi: 10.1111/j.1469-8749.2010.03843.x
This commentary is on the article by Kim et al. on pages 68–73 of this issue.
Does spasticity matter? Kim and Park attempt to answer this
clinical question by applying the technique of pathway analysis
to the problem.1 Should spasticity be treated? This is the topic
of a debate tabled at the 4th World Congress on Controver-
sies in Neurology (CONy) 2010 held in Barcelona. Defini-
tions of spasticity have recently been reviewed2 and it may be
a matter of some concern that out of 250 publications 31%
used the Lance3 definition, 35% used spasticity and increased
muscle tone synonymously, and 31% offered no definition at
all. The same review found 47 papers using neurophysiologi-
cal tests, 228 papers employing biomechanical measurements,
and a further 25 using miscellaneous clinical measures while
19 papers described no actual measure.2
What we consider important today for clinical decision-
making may appear puzzling to future generations of doctors
and allied health professionals. The clinical entity known as
spasticity has been the subject of much study mirroring the
clinical importance attached to the phenomenon. In the
1940s, 50s, and 60s most central motor disorders of childhood
were called ‘spastic’; ‘dystonia’ was not then part of the clinical
vocabulary as it is now. But the term ‘spasticity’ referred to the
whole motor disorder as a syndrome comprising weakness,
lack of distal selective motor control, release of tonic labyrin-
thine responses, poor motor planning and deformity. The
treatment of spasticity then implied the complete management
of the motor syndrome. In the UK, the Spastics Society took
on the role of supporting children and young people with
cerebral palsy. But as the term spastic became increasingly a
term of abuse, the Spastics Society changed its name to
SCOPE, to emphasize a more positive image for its clients. In
the 1980s, following a world conference titled Spasticity, Dis-
ordered Motor Control, the operational definition coined by
Lance3 gained currency and spasticity became defined as a
‘velocity dependent increase in stretch reflexes,’ allowing other
aspects of the motor syndrome to have their own operational
definitions. Spasticity became a precise sign rather than the
syndrome of old, a syndrome being a collection of symptoms
and signs. Despite these changes, old habits die hard in medi-
cal circles and may prevent new ways of understanding motor
disorders in children and young people.
Eighteen years ago, Dr Keith Brown and I published a
paper on the central and peripheral mechanisms of equinus,4
attempting to explore the pathophysiology of this maladaptive
ankle posture, preferring the term ‘dynamic equinus’ (which
describes what the clinician sees) in preference to ‘spastic equi-
nus’ which contains the inherently false supposition that the
equinus posture might be velocity-dependent. We could not
attribute this posture to spasticity but did recognize it as task-
dependent. Keith Brown went on to write an editorial on Sci-
ence and Spasticity for this journal5 attempting to lay bare the
pathophysiological complexity of the motor disorder. But has
our clinical thinking changed?
In 1996, while discussing spasticity on a fellowship in Con-
necticut, a senior orthopaedic colleague uttered the phrase,
‘My neurosurgeon and I speak the same language,’ encapsulat-
ing the problem in a nutshell: our ideas are often driven by the
traditional jargon of medicine. In 2003, a Task Force
attempted to introduce greater operational clarity in our use of
the terms spasticity, dystonia, and rigidity.6 Yet despite this, in
2008 Gainsborough et al.7 found widespread variance in the
clinical classification of cases with total body involvement after
sending case histories to regular contributors of the Surveil-
lance of Cerebral Palsy in Europe Register: cases classified as
dystonic or dyskinetic by half the respondents were classified as
spastic by the other half.7 Who was correct and in the end
would it matter?
Certainly the demographic statistics about cerebral palsy
said to reflect a spastic phenotype in 80% of cases would be
affected. In 2008, the American Association of Neurology
looked at the evidence for the use of botulinum toxin A for the
management of spasticity in adults and children8 but had to
conclude that while changes in the impairment domain (modi-
Commentaries 7
fied Ashworth Scale) could be measured, there was insufficient
evidence supporting improved participation and indepen-
dence, namely functional benefits along the lines of the World
Health Organization International Classification of Function.8
In November 2009, the House of Lords, which is the second
chamber to the UK legislature, held a short debate on cerebral
palsy which discussed the importance of recognizing dystonia
for appropriate clinical care and service development9. Baron-
ess Thornton replying for the then government stated: ‘I want
to put on the record that NICE [the UK National Institute for
Clinical Excellence] has been commissioned to produce guid-
ance on the management of spasticity in children with cerebral
palsy. That will include medicines effective in dystonia9.’
This year has seen the publication of operational definitions
of hyperkinetic movements in childhood again, in an attempt
to bring clear reasoning to our classification for decision-mak-
ing.10
NICE has launched a guideline group for the management
of spasticity, which will include dystonia but only if there is at
least some spasticity. Once established, these guidelines may
risk the possibility that clinicians will adopt ‘spastic spectacles’
and again see spasticity as a means of justifying a variety of
clinical management options, even when spasticity may not
explain the total motor picture1 (see also Fig. 1):11 on this
occasion, attempts to focus the guidelines around the manage-
ment of hypertonus were declined.
Despite this, one thing should remain clear for all clinicians:
our clinical focus should be on restoring function and partici-
pation and independence. To do this we need to continue our
understanding of motor physiology, dysfunction and adaptive
brain development in an often heterogeneous group of move-
ment disorders of childhood of which spasticity may be a com-
ponent, but not necessarily the most important feature.
REFERENCES
1. Kim WH, Park EY. Causal relationship between spasticity,
strength, gross motor function, and functional outcome in
children with cerebral palsy: a path analysis. Dev Med Child
Neurol 2011; 53: 68–73. DOI: 10.1111/j.1469-8749.
2010.03777.x.
2. Malhotra S, PandayanAD, Day CR, Jones PW, Hermens H.
Spasticity, an impairment that is poorly defined and poorly
measured. Clin Rehabil 2009; 23: 651–8.
3. Lance JW. Pathophysiology of spasticity and clinical experi-
ence with baclofen. In: Feldman RG, Young RR, Koella WP,
editors. Spasticity: Disordered Motor Control. Chicago, IL:
Year Book Medical Publishers, 1980: 185–204.
4. Lin JP, Brown JK. Peripheral and central mechanisms of
hindfoot equinus in childhood hemiplegia. Dev Med Child
Neurol 1992; 34: 949–65.
Botulinum toxin A
Baclofen ± ITB
Benzodiazepines
Anticholinergics
Tetrabenazine
Developmental delay and weakness:
Strengthen and support
? Orthopaedic
surgery
?
SDR?
DBS
?
CNS lesion:
subcortical
white matter
basal ganglia
Abnormal muscle
activation patterns and
temporal sequencing
?Dystonia:
inhibited
Cortical/
by sleep
Release of tonic Spinal cord
disinhibition
Trophic changes in
muscles and limb
Immobility over
Dynamic muscle resistance
time and effects
of gravity
Contrature:
inextensible
muscle
shortening
Muscle fibre-type
transformation plastic
muscle change:
EMG silent
EMG-silent
EMG-active
EMG discharges
Spasticity
including clonus:
resistance to passive
stretch reduced muscle
extensibility and joint range
Limb atrophy: skin and
vascular changes
labyrinthine and
neck reflexes
Stretch reflex
stretch reflex
disorder
Posture disorder:
eg hemiplegic posture.
‘scissoring’, ATNR,
fisting. EMG discharge
EMG discharges
active ‘at rest’ and
length-dependent
length-dependent
on passive 
stretching 
Movement disorder
abnormal proximal
to distal muscle
sequencing co-contraction
persistent joint synchrony:
velocity-dependent
Figure 1: Physiological mechanisms of hypertonus from movement disorder to contracture. Spasticity may be present but is it the main problem? DBS, deep
brain stimulation; ITB, intrathecal baclofen; SDR, selective dorsal rhizotomy. ATNR, asymmetrical tonic neck reflex; EMG, electromyography; CNS, central
nervous system. Adapted from Lin 19924 and 2004.11
8 Developmental Medicine & Child Neurology 2011, 53: 5–11
5. Brown JK. Science and spasticity. Dev Med Child Neurol
1993; 35: 471–2.
6. Sanger TD, Delgado MR, Gaebler-Spira D, Hallett M,
Mink JW. Task force on childhood motor disorders. Classi-
fication and definition of disorders causing hypertonia in
childhood. Pediatrics 2003; 111: e89–97.
7. Gainsborough M, Surman G, Maestri G, Colver A, Cans C;
on behalf of the Surveillance of Cerebral Palsy in Europe
collaborative group. Validity and reliability of the guidelines
of the Surveillance of Cerebral Palsy in Europe for the classi-
fication of cerebral palsy. Dev Med Child Neurol 2008; 50:
828–31.
8. Simpson DM, Gracies JM, Graham HK, et al. Assessment:
Botulinum neurotoxin for the treatment of spasticity (an evi-
dence-based review): report of the Therapeutics and Tech-
nology Assessment Subcommittee of the American Academy
of Neurology. Neurology 2008; 70: 1691–8.
9. Health: Cerebral Palsy Question for Short Debate House of
Lords Grand Committees 4 November 2009, Volume No. 714,
Part No. 129.
10. Sanger TD, Chen D, Fehlings DL, et al. Definition and clas-
sification of hyperkinetic movements in childhood. Mov Dis-
ord 2010; 25: 1538–49.
11. Lin J-P. The assessment and management of hypertonus in
cerebral palsy: a physiological atlas (road map). In: Scrutton
D, Damiano D, Mayston M, editors. Management of the
Motor Disorders of Children with Cerebral Palsy. Clinics in
Developmental Medicine No. 161.. London: Mac Keith
Press, 2004: 85–104.
Motor impairment in extremely preterm or low birthweight children
ANNA L BARNETT
Department of Psychology, Oxford Brookes University, Headington Campus, Oxford,
UK.
doi: 10.1111/j.1469-8749.2010.03801.x
This commentary is on the article by Roberts et al. on pages 55–60 of this
issue.
It has long been recognized that extremely preterm and extre-
mely low birthweight (ELBW) children are ‘at risk’ for motor
impairment, with cerebral palsy as the most severe form. Over
the years there has been increased awareness of those children
with less severe motor impairments, which nevertheless have a
negative impact on everyday life. Further studies in this field,
such as that by Roberts et al.1 are vital for increasing our
understanding of motor impairment and how it can best be
identified in these ‘at risk’ groups.
Roberts et al. used the Movement ABC test as an objective
measure of motor impairment in their cohort of extremely
preterm ⁄ extremely low birthweight children at the age of
8 years. The Movement ABC and the Bruininks-Oseretsky
Test of Motor Proficiency have been reported as the most
popular tools to identify motor impairment in these ‘at risk’
groups, involving the assessment of a range of both fine and
gross motor skills. Williams et al.2 note the importance of
using broad assessments like these in order to obtain accurate
rates of impairment. However, more focussed tests are also
needed if we are to elucidate the nature of the motor difficul-
ties in more detail. Armed with knowledge of the medical
histories and patterns of brain damage in these cohorts, clini-
cians may be in a position to hypothesize about the nature of
motor impairment and to include more specific assessments to
test these hypotheses. This might include, for example,
detailed testing of postural control and balance in cases where
there is damage to the underlying motor control systems relat-
ing to these aspects of performance.
Williams et al. have also stressed the importance of using
the most recent revised versions of standardized motor tests to
ensure that prevalence rates are accurately estimated and
advise that results are reported in relation to test norms as well
as to a local reference sample. Unfortunately, local and recent
norms are not always available to researchers and Roberts
et al. used North American test norms that were over 12 years
old with their Australian cohort. However, the inclusion of a
full-term local reference group was useful, allowing them to
check the appropriateness of the rate of moderate impairment,
which they found to be as expected at 5%.
In common with other published studies in this field, Rob-
erts et al. have attempted to identify children in their cohort
who met the formal criteria for a diagnosis of developmental
coordination disorder (DCD). They used the Movement ABC
scores to apply Criterion A from the Diagnostic and Statistical
Manual of Mental Disorders, 4th edition.3 They also excluded
children with cerebral palsy and those with intellectual impair-
ments in order to address Criteria C and D respectively.
15.9% of the cohort were identified in this way, substantially
higher than the 5% in the reference group. To refer to this
group as having DCD, however, is not entirely accurate, as no
reference has been made to Criterion B. The application
of Criterion B confirms that the motor impairment has a
negative impact on academic achievement or activities of daily
living and, when properly taken into account has been found
to give a lower prevalence of DCD of 1.7% in a UK popula-
tion cohort.4 It is recognized that using similar methodology
across studies may aid the direct comparison of results. How-
ever, to use diagnostic terms when not all criteria for the diag-
nosis have been met will create difficulty when attempting to
compare results with fully diagnosed DCD groups in other
studies.
It is usually recommended that results from teacher or par-
ent questionnaires are used to apply Criterion B. Question-
naires can also be employed, as by Roberts et al., in an
attempt to screen for children with motor impairments. How-
ever, the poor sensitivity reported by Roberts et al. serves to
emphasize the need to choose instruments specifically
designed for the purpose of identifying motor impairment in
children. Indeed more specific tools do exist, such as the
recently revised Developmental Coordination Disorder Ques-
tionnaire,5 which has much higher recordedlevels of sensitiv-
ity. While the value of instruments like this in the screening of
‘at risk’ populations needs further examination, they are
already well established as useful in the application of Crite-
rion B for the diagnosis of DCD and should be used more
widely for this purpose.
Commentaries 9