Original research| Volume 99, ISSUE 8, P1547-1552, August 2018

Download started.


Windmill-task as a New Quantitative and Objective Assessment for Mirror Movements in Unilateral Cerebral Palsy: A Pilot Study

Published:March 26, 2018DOI:



      To introduce the Windmill-task, a new objective assessment tool to quantify the presence of mirror movements (MMs) in children with unilateral cerebral palsy (UCP), which are typically assessed with the observation-based Woods and Teuber scale (W&T).


      Prospective, observational, cohort pilot study.


      Children’s hospital.


      Prospective cohort of children (N=23) with UCP (age range, 6–15y, mean age, 10.5±2.7y).


      Not applicable.

      Main Outcome Measures

      The concurrent validity of the Windmill-task is assessed, and the sensitivity and specificity for MM detection are compared between both assessments. To assess the concurrent validity, Windmill-task data are compared with W&T data using Spearman rank correlations (ρ) for 2 conditions: affected hand moving vs less affected hand moving. Sensitivity and specificity are compared by measuring the mean percentage of children being assessed inconsistently across both assessments.


      Outcomes of both assessments correlated significantly (affected hand moving: ρ=.520; P=.005; less affected hand moving: ρ=.488; P=.009). However, many children displayed MMs on the Windmill-task, but not on the W&T (sensitivity: affected hand moving: 27.5%; less affected hand moving: 40.6%). Only 2 children displayed MMs on the W&T, but not on the Windmill-task (specificity: affected hand moving: 2.9%; less affected hand moving: 1.4%).


      The Windmill-task seems to be a valid tool to assess MMs in children with UCP and has an additional advantage of sensitivity to detect MMs.


      List of abbreviations:

      AH (affected hand), CCCmax (maximum cross-correlation coefficient), MACS (Manual Ability Classification System), MM (mirror movement), MVC (maximal voluntary contraction), UCP (unilateral cerebral palsy), W&T (Woods and Teuber scale), W&Tfist (Woods and Teuber fist opening and clenching), W&Topposition (Woods and Teuber finger opposition), W&Ttapping (Woods and Teuber finger tapping)
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Archives of Physical Medicine and Rehabilitation
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Woods B.T.
        • Teuber H.L.
        Mirror movements after childhood hemiparesis.
        Neurology. 1978; 28: 1152-1157
        • Cox B.C.
        • Cincotta M.
        • Espay A.J.
        Mirror movements in movement disorders: a review.
        Tremor Other Hyperkinet Mov (N Y). 2012; 2
        • Connolly K.
        • Stratton P.
        Developmental changes in associated movements.
        Dev Med Child Neurol. 1968; 10: 49-56
        • Carr L.J.
        Development and reorganization of descending motor pathways in children with hemiplegic cerebral palsy.
        Acta Paediatr Suppl. 1996; 416: 53-57
        • Koerte I.
        • Eftimov L.
        • Laubender R.P.
        • et al.
        Mirror movements in healthy humans across the lifespan: effects of development and ageing.
        Dev Med Child Neurol. 2010; 52: 1106-1112
        • Staudt M.
        • Gerloff C.
        • Grodd W.
        • Holthausen H.
        • Niemann G.
        • Krägeloh-Mann I.
        Reorganization in congenital hemiparesis acquired at different gestational ages.
        Ann Neurol. 2004; 56: 854-863
        • Kuhtz-Buschbeck J.P.
        • Sundholm L.K.
        • Eliasson A.C.
        • Forssberg H.
        Quantitative assessment of mirror movements in children and adolescents with hemiplegic cerebral palsy.
        Dev Med Child Neurol. 2000; 42: 728-736
        • Klingels K.
        • Jaspers E.
        • Staudt M.
        • et al.
        Do mirror movements relate to hand function and timing of the brain lesion in children with unilateral cerebral palsy?.
        Dev Med Child Neurol. 2015; 58: 735-742
        • Adler C.
        • Berweck S.
        • Lidzba K.
        • Becher T.
        • Staudt M.
        Mirror movements in unilateral spastic cerebral palsy: specific negative impact on bimanual activities of daily living.
        Eur J Paediatr Neurol. 2015; 19: 504-509
        • Islam M.
        • Gordon A.M.
        • Skold A.
        • Forssberg H.
        • Eliasson A.C.
        Grip force coordination during bimanual tasks in unilateral cerebral palsy.
        Dev Med Child Neurol. 2011; 53: 920-926
        • Holmstrom L.
        • Vollmer B.
        • Tedroff K.
        • et al.
        Hand function in relation to brain lesions and corticomotor-projection pattern in children with unilateral cerebral palsy.
        Dev Med Child Neurol. 2010; 52: 145-152
        • Carr L.J.
        • Harrison L.M.
        • Evans A.L.
        • Stephens J.A.
        Patterns of central motor reorganization in hemiplegic cerebral palsy.
        Brain. 1993; 116: 1223-1247
        • Jaspers E.
        • Byblow W.D.
        • Feys H.
        • Wenderoth N.
        The corticospinal tract: a biomarker to categorize upper limb functional potential in unilateral cerebral palsy.
        Front Pediatr. 2015; 3: 112
        • Friel K.M.
        • Williams P.T.
        • Serradj N.
        • Chakrabarty S.
        • Martin J.H.
        Activity-based therapies for repair of the corticospinal system injured during development.
        Front Neurol. 2014; 5: 229
        • Norton J.A.
        • Thompson A.K.
        • Chan K.M.
        • Wilman A.
        • Stein R.B.
        Persistent mirror movements for over sixty years: the underlying mechanisms in a cerebral palsy patient.
        Clin Neurophysiol. 2008; 119: 80-87
        • Kuhnke N.
        • Juenger H.
        • Walther M.
        • Berweck S.
        • Mall V.
        • Staudt M.
        Do patients with congenital hemiparesis and ipsilateral corticospinal projections respond differently to constraint-induced movement therapy?.
        Dev Med Child Neurol. 2008; 50: 898-903
        • Verstynen T.
        • Spencer R.
        • Stinear C.M.
        • et al.
        Ipsilateral corticospinal projections do not predict congenital mirror movements: a case report.
        Neuropsychologia. 2007; 45: 844-852
        • Staudt M.
        • Pieper T.
        • Adler C.
        • Hessenauer M.
        • Kudernatsch M.
        • Berweck S.
        Ipsilateral motor control without mirror movements?.
        Neuropediatrics. 2012; 43 (FV12_06)
        • Zielinski I.M.
        • Green D.
        • Rudisch J.
        • Jongsma M.L.
        • Aarts P.B.
        • Steenbergen B.
        The relation between mirror movements and non-use of the affected hand in children with unilateral cerebral palsy.
        Dev Med Child Neurol. 2017; 59: 152-159
        • Eliasson A.C.
        • Krumlinde-Sundholm L.
        • Rösblad B.
        • et al.
        The Manual Ability Classification System (MACS) for children with cerebral palsy: scale development and evidence of validity and reliability.
        Dev Med Child Neurol. 2006; 48: 549-554
        • Nelson-Wong E.
        • Howarth S.
        • Winter D.A.
        • Callaghan J.P.
        Application of autocorrelation and cross-correlation analyses in human movement and rehabilitation research.
        J Orthop Sports Phys Ther. 2009; 39: 287-295
        • Mukaka M.M.
        Statistics corner: a guide to appropriate use of correlation coefficient in medical research.
        Malawi Med J. 2012; 24: 69-71
        • Staudt M.
        Should mirror movements modify therapeutic strategies for unilateral spastic cerebral palsy?.
        Dev Med Child Neurol. 2017; 59: 114-115