An investigation into the agreement between clinical, biomechanical and neurophysiological measures of spasticity

Objective: To quantify agreement between three clinically usable methods of measuring spasticity. Methods: Patients with a first stroke who had no useful functional movement in the upper limb within six weeks from stroke onset were eligible to participate. Spasticity at the wrist joint was simultaneously measured using three methods, during an externally imposed passive stretch at two (uncontrolled) displacement velocities. The measures used were a common clinical measure (modified Ashworth Scale), a biomechanical measure (resistance to passive movement) and a neurophysiological measure (muscle activity). Results: One hundred patients (54 men and 46 women) with a median age of 74 years (range 43—91) participated. Median time since stroke was three weeks (range 1—6), the right side was affected in 52 patients and the left in 48 patients. Based on muscle activity measurement, 87 patients had spasticity. According to the modified Ashworth score 44 patients had spasticity. Sensitivity of modified Ashworth score, when compared with muscle activity recordings, was 0.5 and specificity was 0.92. Based on muscle activity patterns, patients could be classified into five subgroups. The biomechanical measures showed no consistent relationship with the other measures. Conclusion: The presentations of spasticity are variable and are not always consistent with existing definitions. Existing clinical scales that depend on the quantification of muscle tone may lack the sensitivity to quantify the abnormal muscle activation and stiffness associated with common definitions of spasticity. Neurophysiological measures may provide more clinically useful information for the management and assessment of spasticity.

[1]  R. Lyle.  A performance test for assessment of upper limb function in physical rehabilitation treatment and research , 1981, International journal of rehabilitation research. Internationale Zeitschrift fur Rehabilitationsforschung. Revue internationale de recherches de readaptation.

[2]  M. V. von Arbin,et al.  Spasticity After Stroke: Its Occurrence and Association With Motor Impairments and Activity Limitations , 2003, Stroke.

[3]  Douglas G. Altman,et al.  Statistics with confidence. 2nd edition , 2000 .

[4]  K. Harms-Ringdahl,et al.  Simultaneous Ashworth measurements and electromyographic recordings in tetraplegic patients. , 1998, Archives of physical medicine and rehabilitation.

[5]  M. Leathley,et al.  Prevalence of spasticity post stroke , 2002, Clinical rehabilitation.

[6]  Richard W. Bohannon,et al.  Interrater reliability of hand-held dynamometry. , 1987, Physical therapy.

[7]  W. Akeson,et al.  Spasticity and contracture. Physiologic aspects of formation. , 1988, Clinical orthopaedics and related research.

[8]  A. Lahunta.  Chapter 8 – Upper Motor Neuron , 2009 .

[9]  Steven White,et al.  Upper Motor Neurone Syndrome and Spasticity: Clinical Management and Neurophysiology , 2001 .

[10]  M. Reding,et al.  Dose-dependent response to intramuscular botulinum toxin type A for upper-limb spasticity in patients after a stroke. , 2004, Archives of physical medicine and rehabilitation.

[11]  A. Rodriquez,et al.  Botulinum toxin injection of spastic finger flexors in hemiplegic patients. , 2000, American journal of physical medicine & rehabilitation.

[12]  D Burke,et al.  Spasticity as an adaptation to pyramidal tract injury. , 1988, Advances in neurology.

[13]  J. Bamford,et al.  Classification and natural history of clinically identifiable subtypes of cerebral infarction , 1991, The Lancet.

[14]  D. Denny-Brown,et al.  cerebral control of movement , 1966 .

[15]  H Rodgers,et al.  Biomechanical examination of a commonly used measure of spasticity. , 2001, Clinical biomechanics.

[16]  Sean OʼReilly.  The Cerebral Control of Movement [Sherrington Lectures, 1963] , 1967 .

[17]  R. Young,et al.  Spasticity, disordered motor control , 1980 .

[18]  AD Pandyan,et al.  Spasticity: Clinical perceptions, neurological realities and meaningful measurement , 2005, Disability and rehabilitation.

[19]  Michael P Barnes,et al.  Are we underestimating the clinical efficacy of botulinum toxin (type A)? Quantifying changes in spasticity, strength and upper limb function after injections of Botox® to the elbow flexors in a unilateral stroke population , 2002, Clinical rehabilitation.

[20]  Michael P Barnes,et al.  A biomechanical investigation into the validity of the modified Ashworth Scale as a measure of elbow spasticity , 2003, Clinical rehabilitation.

[21]  Alberto Esquenazi.  Upper motor neurone syndrome and spasticity Michael P. Barnes Garth R , 2009, The Lancet Neurology.

[22]  Sandra C. Stark,et al.  The construct validity of a spasticity measurement device for clinical practice: An alternative to the Ashworth scales , 2006, Disability and rehabilitation.

[23]  M. Hallett,et al.  Classification and definition of disorders causing hypertonia in childhood. , 2003, Pediatrics.