title: Electromyographic characteristics of gait impairment in cervical spondylotic myelopathy.
abstract: OBJECTIVE
  Gait impairment in cervical spondylotic myelopathy (CSM) is characterised by a number of kinematic and kinetic abnormalities. Surface electromyography (EMG) can evaluate the contributions of individual muscles to a movement pattern and provide insight into the underlying impairments that characterise an abnormal gait. This study aimed to analyse EMG signals from major lower limb muscles in people with CSM and healthy controls during gait.
  
  
  METHODS
  Sixteen people with radiologically confirmed CSM and 16 matched healthy controls participated in gait analysis. Surface EMG was recorded during walking from four lower limb muscles bilaterally. The timing of muscle activation, relative amplitudes of each burst of activity and baseline activation during gait, and the muscles' responses to lengthening as a measure of spasticity were compared using previously validated methods of EMG analysis.
  
  
  RESULTS
  Compared to healthy controls, people with CSM had prolonged duration of activation of biceps femoris (12.5% longer) and tibialis anterior (12.4%), prolonged co-activation of rectus femoris and biceps femoris (5.14%), and impaired scaling of the amplitude of rectus femoris and biceps femoris. Muscle activation in response to lengthening was similar between groups.
  
  
  CONCLUSIONS
  The results provide evidence for paresis as a contributory factor to gait impairment in CSM, indicated by impaired amplitude and the need for proximal co-activation to compensate for lack of distal power generation. Poor proprioception may have contributed to prolonged activation of tibialis anterior. Analysis of muscle responses to lengthening suggested that spasticity was not an important contributor. These findings have implications for the assessment and rehabilitation of gait impairment in CSM.
authors.affiliation: Gait Analysis Laboratory, Central Remedial Clinic, Clontarf, Dublin 3, Ireland, ammalone@crc.ie.
authors.forename: Ailish
authors.initials: A
authors.lastname: Malone
authors.forename: Dara
authors.initials: D
authors.lastname: Meldrum
authors.forename: John
authors.initials: J
authors.lastname: Gleeson
authors.forename: Ciaran
authors.initials: C
authors.lastname: Bolger
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae; D004576:Electromyography; D005260:Female; D020233:Gait Disorders, Neurologic / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009135:Muscular Diseases / Q000175:diagnosis* / Q000209:etiology; D013118:Spinal Cord Diseases / Q000175:diagnosis* / Q000209:etiology; D055009:Spondylosis / Q000150:complications*
references.citation: Spine (Phila Pa 1976). 2005 Jan 1;30(1):83-6
references.pmid: 15626986
references.citation: Phys Ther. 2009 Nov;89(11):1205-14
references.pmid: 19778980
references.citation: Clin Biomech (Bristol, Avon). 2009 Feb;24(2):122-34
references.pmid: 19042063
references.citation: Arch Phys Med Rehabil. 2001 Dec;82(12):1696-704
references.pmid: 11733885
references.citation: J Electromyogr Kinesiol. 2000 Dec;10(6):407-15
references.pmid: 11102843
references.citation: J Neurol Neurosurg Psychiatry. 2003 Jun;74(6):820-1
references.pmid: 12754364
references.citation: Gait Posture. 2003 Oct;18(2):109-17
references.pmid: 14654214
references.citation: J Electromyogr Kinesiol. 2011 Dec;21(6):1004-10
references.pmid: 21986038
references.citation: Clin Biomech (Bristol, Avon). 2009 Mar;24(3):236-45
references.pmid: 18995937
references.citation: J Neurosurg Spine. 2005 Apr;2(4):418-24
references.pmid: 15871480
references.citation: Neurophysiol Clin. 2005 Jul;35(2-3):59-71
references.pmid: 16087069
references.citation: J Rehabil Res Dev. 1987 Spring;24(2):24-30
references.pmid: 3585782
references.citation: Disabil Rehabil. 2005 Jan 7-21;27(1-2):2-6
references.pmid: 15799140
references.citation: Gait Posture. 2007 Jul;26(2):279-88
references.pmid: 17071088
references.citation: Eur Spine J. 2012 Dec;21(12):2456-66
references.pmid: 22825630
references.citation: J Electromyogr Kinesiol. 1991 Dec;1(4):263-9
references.pmid: 20870517
references.citation: J Manipulative Physiol Ther. 1999 Sep;22(7):444-6
references.pmid: 10519560
references.citation: J Spinal Disord Tech. 2002 Dec;15(6):519-22
references.pmid: 12468981
references.citation: Gait Posture. 2008 Apr;27(3):399-407
references.pmid: 18023352
references.citation: Eur Spine J. 2015 Apr;24 Suppl 2:236-51
references.pmid: 23386279
references.citation: Gait Posture. 2011 Mar;33(3):319-20
references.pmid: 21131204
references.citation: J Electromyogr Kinesiol. 2003 Dec;13(6):519-32
references.pmid: 14573367