Michael P. Barnes

A review of the properties and limitations of the Ashworth and modified Ashworth Scales as measures of spasticity

Background: The Ashworth Scale and the modified Ashworth Scale are the primary clinical measures of spasticity. A prerequisite for using any scale is a knowledge of its characteristics and limitations, as these will play a part in analysing and interpreting the data. Despite the current emphasis on treating spasticity, clinicians rarely measure it. Objectives: To determine the validity and the reliability of the Ashworth and modified Ashworth Scales. Study design: A theoretical analysis following a structured literature review (key words: Ashworth; Spasticity; Measurement) of 40 papers selected from the BIDS-EMBASE, First Search and Medline databases. Conclusions: The application of both scales would suggest that confusion exists on their characteristics and limitations as measures of spasticity. Resistance to passive movement is a complex measure that will be influenced by many factors, only one of which could be spasticity. The Ashworth Scale (AS) can be used as an ordinal level measure of resistance to passive movement, but not spasticity. The modified Ashworth Scale (MAS) will need to be treated as a nominal level measure of resistance to passive movement until the ambiguity between the ‘1’ and ‘1+’ grades is resolved. The reliability of the scales is better in the upper limb. The AS may be more reliable than the MAS. There is a need to standardize methods to apply these scales in clinical practice and research.

Spasticity: Clinical perceptions, neurological realities and meaningful measurement

The aim of this paper is to review briefly our understanding of the phenomenon of spasticity based in current evidence.

Rehabilitation after traumatic brain injury

Head injury is a common disabling condition but regrettably facilities for rehabilitation are sparse. There is now increasing evidence of the efficacy of a comprehensive multidisciplinary rehabilitation team compared to natural recovery following brain injury. This chapter outlines some basic concepts of rehabilitation and emphasises the importance of valid and reliable outcome measures. The evidence of the efficacy of a rehabilitation programme is discussed in some detail. A number of specific rehabilitation problems are outlined including the management of spasticity, nutrition, pressure sores and urinary continence. The increasingly important role of assistive technology is illustrated, particularly in terms of communication aids and environmental control equipment. However, the major long-term difficulties after head injury focus around the cognitive, intellectual, behavioural and emotional problems. The complex management of these disorders is briefly addressed and the evidence of the efficacy of some techniques discussed. The importance of recognition of the vegetative stage and avoidance of misdiagnosis is emphasised. Finally, the important, but often neglected, area of employment rehabilitation is covered.

A biomechanical investigation into the validity of the modified Ashworth Scale as a measure of elbow spasticity

Objective: To investigate the criterion validity of the modified Ashworth Scale. Population: Volunteers from a stroke population admitted to a district general hospital stroke unit diagnosed with a first ever stroke less than 26 weeks previously. Outcome measures: Resistance to passive movement about the elbow was simultaneously quantified (biomechanically) and graded (modified Ashworth Scale). Passive range of movement and peak instantaneous velocity during passive movement were also measured. Analysis: Criterion validity was investigated as convergent construct validity (using the Spearmans correlation coefficient) and concurrent validity (using analysis of variance). Results: One hundred measurements were taken on 63 subjects. Correlation between the modified Ashworth Scale and resistance to passive movement was 0.511. Resistance to passive movement and velocity showed significant differences between the modified Ashworth score of ‘0’ and a modified Ashworth score greater than ‘0’ (p < 0.01). There were no significant differences between MAS ‘1’, ‘1+’ and ‘2’. Resistance to passive movement in the impaired arm was significantly higher than in the nonimpaired arm (p < 0.01). Conclusion: The modified Ashworth Scale does not provide a valid measure of spasticity at lower grades but it may provide a measure of resistance to passive movement.

Spasticity in multiple sclerosis

The objective of this article is to establish the prevalence of spasticity in a random selection of people with multiple sclerosis (MS) in the city of Newcastle upon Tyne in the Northeast of England. A secondary aim was to assess the adequacy of current pharmacological intervention for spasticity and assess the relationship between spasticity and overall disability. The study design was a simple comparison that examined differences in functional independence in 2 random groups of people with MS subdivided by the presence of clinically significant spasticity. A total of 68 adults with a diagnosis of clinically definite MS were included in the study. Their level of functional independence was assessed using the Newcastle Independence Assessment Form (NIAF), the Functional Independence Measure (FIM), and the Kurtzke Extended Disability Status Scale (EDSS). Spasticity was assessed using the Modified Ashworth Scale. A subjective analysis was made of the appropriateness of oral antispastic medication by a rehabilitation physician. Thirty-two people (47%) had clinically significant spasticity (Modified Ashworth Score of 2, 3, or 4). Seventy-eight percent of the population were receiving some oral antispastic medication, but 50% were deemed to require some drug adjustment or additional treatment. Individuals with spasticity were found to have significantly higher levels of disability than those who had no spasticity or clinically insignificant spasticity. This study has confirmed that spasticity is highly prevalent in the MS population and is significantly associated with a reduced level of functional independence. Treatment of spasticity is suboptimal in a large proportion of the population, and the need for further information and education to health professionals and to people with MS is highlighted.

Traumatic brain injury: Efficacy of multidisciplinary rehabilitation

OBJECTIVE To establish efficacy of a coordinated multidisciplinary rehabilitation service for severe head injury, provided at Hunters Moor Regional Rehabilitation Centre. DESIGN A quasi-experimental design to compare treatment effects between two groups. The first group received a coordinated, multidisciplinary regional rehabilitation service; the other, a single discipline approach provided by local, district hospitals. Follow-up was for 2 years postinjury. PATIENTS OR OTHER PARTICIPANTS Fifty-six consecutive severe head injury admissions, with an identified main caregiver, referred for rehabilitation within 4 weeks of their injury. MAIN OUTCOME MEASURES The Barthel index, the Functional Independence Measure (FIM), and the Newcastle Independence Assessment Form (NIAF), a newly developed, real-life, comprehensive measure. In addition, caregivers completed the General Health Questionnaire. RESULTS The group that received coordinated multidisciplinary rehabilitation not only demonstrated significant gains throughout the study period but also maintained treatment effect after input ended. Furthermore, caregivers of this group had significantly reduced levels of distress. The comparison group, despite initial lower injury severity and shorter hospital stay, did not demonstrate equivalent gains or any posttreatment effect. CONCLUSIONS The results show the efficacy of a comprehensive, specialist multidisciplinary regional service. There are significant implications for service provision for people with severe traumatic head injury.

Botulinum Toxin for the Upper Limb After Stroke (BoTULS) Trial Effect on Impairment, Activity Limitation, and Pain

Background and Purpose— Botulinum toxin is increasingly used to treat upper limb spasticity due to stroke, but its impact on arm function is unclear. We evaluated botulinum toxin for upper limb spasticity and function poststroke. Methods— Three hundred thirty-three patients with stroke with upper limb spasticity and reduced arm function participated in a multicenter randomized controlled trial. The intervention group received botulinum toxin type A injection(s) plus a 4-week therapy program. The control group received the therapy program alone. Repeat injection(s) and therapy were available at 3, 6, and 9 months. The primary outcome was upper limb function at 1 month (Action Research Arm Test). Secondary outcomes included measures of impairment, activity limitation, and pain at 1, 3, and 12 months. Outcome assessments were blinded and analysis was by intention to treat. Results— There was no significant difference in achievement of improved arm function (Action Research Arm Test) at 1 month (intervention group: 42 of 167 [25.1%], control group 30 of 154 [19.5%]; P=0.232). Significant differences in favor of the intervention group were seen in muscle tone at 1 month; upper limb strength at 3 months; basic arm functional tasks (hand hygiene, facilitation of dressing) at 1, 3, and 12 months; and pain at 12 months. Conclusions— Botulinum toxin type A is unlikely to be useful for improving active upper limb function (eg, reaching and grasping) in the majority of patients with spasticity after stroke, but it may improve basic upper limb tasks (hand hygiene, facilitation of dressing) and pain.

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

Objective: To quantify the clinical efficacy of botulinum toxin type A in treating elbow flexor spasticity in a unilateral stroke population. Location: A spasticity clinic at a regional neurological rehabilitation centre. Study design: A convenience sample longitudinal study. Fourteen subjects with elbow flexor spasticity secondary to a stroke were recruited. Two repeated measures, one before and another four weeks after treatment, were taken to quantify clinical efficacy. Outcome measures: Elbow flexor spasticity was simultaneously rated with the modified Ashworth scale (MAS) and quantified by measuring the surface EMG from the flexors using a custom-built device. Strength at the elbow (isometric), grip strength and upper limb function (Action Research Arm test) were also assessed. Treatment: Injections of botulinum toxin type A (Botox®) to the m.biceps brachii (mean dose 70 U), m.brachioradialis (mean dose 56.5 U) and m.flexor digitorum longus (mean dose 83.3 U). Results: Following treatment, spasticity (as measured by flexor EMG activity) reduced but the MAS was unable to detect this improvement. In some subjects, isometric flexor strength at the elbow as well as grip strength increased. This was contrary to the expected weakening following treatment with botulinum toxin type A and suggests an optimization of motor control. Conclusion: Treatment with Botox® reduces spasticity but does not necessarily cause a reduction in the force generating capabilities at the joint. The improvement in strength may have contributed to the improvements in upper limb function. The MAS is an inappropriate measure of spasticity.

Assessing Motor Deficits in Neurological Rehabilitation: Patterns of Instrument Usage

To describe current patterns in the use of clinical scales and measurement tech nology for the assessment of motor deficits in neurological rehabilitation. Question naire, sent to the 2,556 members of the World Forum for Neurological Rehabilita tion, distributed over 75 countries. Sixty-eight questionnaires were returned. Generally, participants indicated that the centres where they were based used a num ber of different clinical assessment scales (median, three), most frequently with a small proportion of patients. The (Modified) Ashworth Scale, the FIM, and the Fugl-Meyer were used most frequently. Only 35 respondents stated that their centre used one or more scales in >75% of their patients, but the choice of such routinely applied in struments varied between centres. The application of measurement technology was re stricted, with video and goniometry being used most frequently. The main barriers to more frequent use of assessment tools were perceived to be a lack of resources, infor mation, and training. The (albeit limited) results from this survey suggest that the assessment of motor deficits in neurological rehabilitation is currently mostly qualita tive and lacks standardisation. More resources and education are required to support a more routine application of assessment tools and to integrate measurement tech nology further in neurological rehabilitation to assist in the process of quantification of outcomes. Key Words: Motor deficits—Neurological rehabilitation—Outcome as sessment—Standardisation—Measurement technology.

Developing Core Sets for Persons With Traumatic Brain Injury Based on the International Classification of Functioning, Disability, and Health:

The authors outline the process for developing the International Classification of Functioning, Disability, and Health (ICF) Core Sets for traumatic brain injury (TBI). ICF Core Sets are selections of categories of the ICF that identify relevant categories of patients affected by specific diseases. Comprehensive and brief ICF Core Sets for TBI should become useful for clinical practice and for research. The final definition of the ICF Core Sets for TBI will be determined at an ICF Core Sets Consensus Conference, which will integrate evidence from preliminary studies. The development of ICF Core Sets is an inclusive and open process and rehabilitation professionals are invited to participate.