Assistive technologies, including orthotic devices, for the management of contractures in adults after a stroke.

BACKGROUND: Contractures (reduced range of motion and increased stiffness of a joint) are a frequent complication of stroke. Contractures can interfere with function and cause cosmetic and hygiene problems. Preventing and managing contractures might improve rehabilitation and recovery after stroke. OBJECTIVES: To assess the effects of assistive technologies for the management of contractures in adults after a stroke. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, five other databases, and three trials registers in May 2022. We also searched for reference lists of relevant studies, contacted experts in the field, and ran forward citation searches. SELECTION CRITERIA: Randomised controlled studies (RCTs) that used electrical, mechanical, or electromechanical devices to manage contractures in adults with stroke were eligible for inclusion in this review. We planned to include studies that compared assistive technologies against no treatment, routine therapy, or another assistive technology. DATA COLLECTION AND ANALYSIS: Three review authors (working in pairs) selected all studies, extracted data, and assessed risk of bias. The primary outcomes were passive joint range of motion (PROM) with and without standardised force, and indirect measures of PROM. The secondary outcomes included hygiene. We also wanted to evaluate the adverse effects of assistive technology. Effects were expressed as mean differences (MDs) or standardised mean differences (SMDs) with 95% confidence intervals (CIs). MAIN RESULTS: Seven studies fulfilled the inclusion criteria. Five of these were meta-analysed; they included 252 adults treated in acute and subacute rehabilitation settings. All studies compared assistive technology with routine therapy; one study also compared assistive technology with no treatment, but we were unable to obtain separate data for stroke participants. The assistive technologies used in the studies were electrical stimulation, splinting, positioning using a hinged board, and active repetitive motor training using a non-robotic device with electrical stimulation. Only one study applied stretching to end range. Treatment duration ranged from four to 12 weeks. The overall risk of bias was high for all studies. We are uncertain whether: • electrical stimulation to wrist extensors improves passive range of wrist extension (MD -7.30°, 95% CI -18.26° to 3.66°; 1 study, 81 participants; very low-certainty evidence); • a non-robotic device with electrical stimulation to shoulder flexors improves passive range of shoulder flexion (MD -9.00°, 95% CI -25.71° to 7.71°; 1 study; 50 participants; very low-certainty evidence); • assistive technology improves passive range of wrist extension with standardised force (SMD -0.05, 95% CI -0.39 to 0.29; four studies, 145 participants; very low-certainty evidence): • a non-robotic device with electrical stimulation to elbow extensors improves passive range of elbow extension (MD 0.41°, 95% CI -0.15° to 0.97°; 1 study, 50 participants; very low-certainty evidence). One study reported the adverse outcome of pain when using a hinged board to apply stretch to wrist and finger flexors, and another study reported skin breakdown when using a thumb splint. No studies reported hygiene or indirect measures of PROM. AUTHORS' CONCLUSIONS: Only seven small RCTs met the eligibility criteria of this review, and all provided very low-certainty evidence. Consequently, we cannot draw firm conclusions on the effects of assistive technology compared with routine therapy or no therapy. It was also difficult to confirm whether there is a risk of harm associated with treatment using assistive technology. Future studies should apply adequate treatment intensity (i.e. magnitude and the duration of stretch) and use valid and reliable outcome measures. Such studies might better identify the role of assistive technology in the management of contractures in adults after a stroke.

The ESCAPS study: a feasibility randomized controlled trial of early electrical stimulation to the wrist extensors and flexors to prevent post-stroke complications of pain and contractures in the paretic arm.

OBJECTIVE: To establish feasibility of initiating electrical stimulation treatment of wrist extensors and flexors in patients early after stroke to prevent muscle contractures and pain. DESIGN: Feasibility randomized controlled trial with economic evaluation. SETTING: A specialist stroke unit in Nottinghamshire. SUBJECTS: A total of 40 patients recruited within 72 hours post-stroke with arm hemiparesis. INTERVENTIONS: Participants were randomized to receive usual care or usual care and electrical stimulation to wrist flexors and extensors for 30 minutes, twice a day, five days a week for three months. Initial treatment was delivered by an occupational therapist or physiotherapist who trained participants to self-manage subsequent treatments. MEASURES: Measures of feasibility included recruitment and attrition rates, completion of treatment, and successful data collection. Outcome data on wrist range of motion, pain, arm function, independence, quality of life, and resource use were measured at 3-, 6-, and 12-months post-randomization. RESULTS: A total of 40 participants (of 215 potentially eligible) were recruited in 15 months (20 men; mean age: 72 (SD: 13.0)). Half the participants lacked mental capacity and were recruited by consultee consent. Attrition at three-month follow-up was 12.5% (death (n = 2), end-of-life care (n = 2), and unable to contact (n = 1)). Compliance varied (mean: 65 (SD: 53)) and ranged from 10 to 166 treatments per patient (target dosage was 120). Data for a valid economic analysis can be adequately collected. CONCLUSION: Early initiation of electrical stimulation was acceptable and feasible. Data collection methods used were feasible and acceptable to participants. A large definitive study is needed to determine if electrical stimulation is efficacious and cost effective.

Study of the measurement and predictive validity of the Functional Movement Screen.

OBJECTIVE: The aim of the study was to evaluate the reported measurement capabilities and predictive validity of the Functional Movement Screen (FMS) for injury. METHODS: This was a prospective observational longitudinal study of 24 male footballers from a single team in England, alongside analysis of an existing database over one season (September 2015-May 2016). A preseason FMS was carried out with scores recorded by an experienced assessor and derived, retrospectively, from the three-dimensional movement data that were simultaneously captured. The assessor scores were compared with the photogrammetric system to determine measurement validity, and predictive validity was quantified by assessing sensitivity and specificity (cut-off score of 14). RESULTS: The real-time assessor score matched the photogrammetric score awarded for one of the participants, was higher than the photogrammetric system for 22 participants and was lower than the photogrammetric system in 1 participant. There was no discernible relationship between FMS scores and the competencies required to be met as per the rules articulated for the allocation of a score. A higher number of total injuries were associated with higher FMS scores, whether determined through real-time assessment or codification of kinematic variables. Additionally, neither method of score determination was able to prospectively identify players at risk of serious injury. CONCLUSION: The FMS does not demonstrate the properties essential to be considered as a measurement scale and has neither measurement nor predictive validity. A possible reason for these observations could be the complexity in the instructions associated with the scale. Further work on eliminating redundancies and improving the measurement properties is recommended.

Pharmacological interventions other than botulinum toxin for spasticity after stroke.

BACKGROUND: The long-term risk of stroke increases with age, and stroke is a common cause of disability in the community. Spasticity is considered a significantly disabling impairment that develops in people who have had a stroke. The burden of care is higher in stroke survivors who have spasticity when compared with stroke survivors without spasticity with regard to treatment costs, quality of life, and caregiver burden. OBJECTIVES: To assess if pharmacological interventions for spasticity are more effective than no intervention, normal practice, or control at improving function following stroke. SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register (May 2016), the Cochrane Central Register of Controlled Trials (CENTRAL, 2016, Issue 5), MEDLINE (1946 to May 2016), Embase (2008 to May 2016), CINAHL (1982 to May 2016), AMED (1985 to May 2016), and eight further databases and trial registers. In an effort to identify further studies, we undertook handsearches of reference lists and contacted study authors and commercial companies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that compared any systemically acting or locally acting drug versus placebo, control, or comparative drug with the aim of treating spasticity. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed the studies for inclusion and extracted the data. We assessed the included studies for both quality and risk of bias. We contacted study authors to request further information when necessary. MAIN RESULTS: We included seven RCTs with a total 403 participants. We found a high risk of bias in all but one RCT. Two of the seven RCTs assessed a systemic drug versus placebo. We pooled data on an indirect measure of spasticity (160 participants) from these two studies but found no significant effect (odds ratio (OR) 1.66, 95% confidence interval (CI) 0.21 to 13.07; I2 = 85%). We identified a significant risk of adverse events per participant occurring in the treatment group versus placebo group (risk ratio (RR) 1.65, 95% CI 1.12 to 2.42; 160 participants; I2 = 0%). Only one of these studies used a functional outcome measure, and we found no significant difference between groups.Of the other five studies, two assessed a systemic drug versus another systemic drug, one assessed a systemic drug versus local drug, and the final two assessed a local drug versus another local drug. AUTHORS' CONCLUSIONS: The lack of high-quality RCTs limited our ability to make specific conclusions. Evidence is insufficient to determine if systemic antispasmodics are effective at improving function following stroke.

ESCAPS study protocol: a feasibility randomised controlled trial of 'Early electrical stimulation to the wrist extensors and wrist flexors to prevent the post-stroke complications of pain and contractures in the paretic arm'.

INTRODUCTION: Approximately 70% of patients with stroke experience impaired arm function, which is persistent and disabling for an estimated 40%. Loss of function reduces independence in daily activities and impacts on quality of life. Muscles in those who do not recover functional movement in the stroke affected arm are at risk of atrophy and contractures, which can be established as early as 6 weeks following stroke. Pain is also common. This study aims to evaluate the feasibility of a randomised controlled trial to test the efficacy and cost-effectiveness of delivering early intensive electrical stimulation (ES) to prevent post-stroke complications in the paretic upper limb. METHODS AND ANALYSIS: This is a feasibility randomised controlled trial (n=40) with embedded qualitative studies (patient/carer interviews and therapist focus groups) and feasibility economic evaluation. Patients will be recruited from the Stroke Unit at the Nottingham University Hospitals National Health Service (NHS) Trust within 72 h after stroke. Participants will be randomised to receive usual care or usual care and early ES to the wrist flexors and extensors for 30 min twice a day, 5 days a week for 3 months. The initial treatment(s) will be delivered by an occupational therapist or physiotherapist who will then train the patient and/or their nominated carer to self-manage subsequent treatments. ETHICS AND DISSEMINATION: This study has been granted ethical approval by the National Research Ethics Service, East Midlands Nottingham1 Research Ethics Committee (ref: 15/EM/0006). To our knowledge, this is the first study of its kind of the early application (within 72 h post-stroke) of ES to both the wrist extensors and wrist flexors of stroke survivors with upper limb impairment. The results will inform the design of a definitive randomised controlled trial. Dissemination will include 2 peer-reviewed journal publications and presentations at national conferences. TRIAL REGISTRATION NUMBER: ISRCTN1648908; Pre-results. Clinicaltrials.gov ID: NCT02324634.

Is the practice of goal-setting for patients in acute stroke care patient-centred and what factors influence this? A qualitative study.

OBJECTIVE: To explore whether goal-setting for rehabilitation with acute stroke survivors is patient-centred and identify factors which influence the adoption of patient-centredness in goal-setting practice. SETTING: Acute stroke unit in a large teaching hospital in England. PARTICIPANTS: Patients with stroke who had no cognitive or significant communication problems and health care professionals who had a significant engagement with an individual patient were approached for participation. METHOD: Multiple qualitative methods were used. Perceptions and beliefs about patient-centredness, within the context of goal-setting, were collected from patients and corresponding professionals using qualitative semi-structured interviews. Adoption of patient-centred behaviour was triangulated using analysis of patient records and observation of team meetings related to participating patients. DATA ANALYSIS: Interview transcripts and field notes were coded, clustered under categories and descriptively summarised. Additionally, data from patients' documents were summarised. These summaries were then mapped on to an a-priori frame work of patient-centredness from which further interpretative themes were derived. RESULTS: Seven patients and seven health-care professionals participated. Goal-setting was not consistently patient-centred as evidenced by a) incongruities between patients and professionals in setting, communicating and prioritising of goals and b) dysfunctional therapeutic relationships. The factors that influenced patient-centred goal-setting were both professional and patient beliefs and attributes, work-culture, practice model, limitations in knowledge and systems that disempowered both professionals and patients. CONCLUSION: It may be possible to infer that current local practice of goal-setting was inadequately patient-centred. Further research is required to identify strategies to overcome these challenges and to develop patient-centred goal-setting methods.

The early use of botulinum toxin in post-stroke spasticity: study protocol for a randomised controlled trial.

BACKGROUND: Patients surviving stroke but who have significant impairment of function in the affected arm are at more risk of developing pain, stiffness and contractures. The abnormal muscle activity, associated with post-stroke spasticity, is thought to be causally associated with the development of these complications. Treatment of spasticity is currently delayed until a patient develops signs of these complications. METHODS/DESIGN: This protocol is for a phase II study that aims to identify whether using OnabotulinumtoxinA (BoNT-A) in combination with physiotherapy early post stroke when initial abnormal muscle activity is neurophysiologically identified can prevent loss of range at joints and improve functional outcomes.The trial uses a screening phase to identify which people are appropriate to be included in a double blind randomised placebo-controlled trial. All patients admitted to Sandwell and West Birmingham NHS Trust Hospitals with a diagnosis of stroke will be screened to identify functional activity in the arm. Those who have no function will be appropriate for further screening. Patients who are screened and have abnormal muscle activity identified on EMG will be given electrical stimulation to forearm extensors for 3 months and randomised to have either injections of BoNT-A or normal saline. The primary outcome measure is the action research arm test - a measure of arm function. Further measures include spasticity, stiffness, muscle strength and fatigue as well as measures of quality of life, participation and caregiver strain. TRIAL REGISTRATIONS: ISRCTN57435427, EudraCT2010-021257-39, NCT01882556.

The physiological impact of upper limb position in prone restraint.

Deaths occurring during and/or in close proximity to physical restraint have been attributed to positional asphyxia. This study investigated the physiological impact of three recognized prone-restraint positions with participants remaining passive. Position 3 (P3) the supported prone position (SPP) was designed to reduce the extent of pressure on the anterior chest wall (PAC) by bringing the upper limbs underneath the shoulder joint whereas for the other two positions (P1 and P2) the arms were abducted from the torso. Twenty-five adults participated. Forced vital capacity (FVC), expiratory volume in one second (FEV1), heart rate (HR) and oxygen saturations (SpO2) were taken three times in an upright seated position (baseline) and in each prone position. Mean PAC was measured at 102.6 (±24.3) and 101.4 (±24.4) mmHg for P1 and P2, respectively; however, in the SPP (P3) the mean PAC pressure reduced to 72.7 (±16.9) mmHg. All three prone-restraint positions reduced FVC and FEV1 compared with baseline (P < 0.001). P1 and P2 where the arms were abducted reduced respiratory measures equally but differed from the SPP position (P < 0.001) where PAC was significantly lower. Reductions in FVC from baseline were 16% for P1 and P2, and 11% for the SPP (P3) where PAC was ∼28% lower than in P1 and P2. Reductions in FEV1 were similar in all three prone-restraint positions and HR and SpO2 were unaffected. In summary, all prone-restraint positions restrict respiratory function but the risk associated with the position reduces as the PAC reduces.

Assessment of the risk of bias in rehabilitation reviews.

Systematic reviews are used to inform practice, and develop guidelines and protocols. A questionnaire to quantify the risk of bias in systematic reviews, the review paper assessment (RPA) tool, was developed and tested. A search of electronic databases provided a data set of review articles that were then independently reviewed by two assessors using the RPA. The inter-rater reliability was between moderate and good (κ scores 0.46-0.95). Many reviews did not describe the purpose in terms of population, intervention, comparator and outcome measure (i.e. PICO format), making inter-rater agreement on this question difficult. The RPA discriminated between high-quality reviews and those with a risk of bias (e.g. inadequate reporting of search terms, lack of independent reviewing or inclusion of non-randomized-controlled trials). The RPA questionnaire was revised to ensure that questions (on the basis of clarity of purpose, extent of search, independence of reviewers, randomized-controlled trial inclusion and availability of data) had dichotomous answers so that the positive responses scored one. The risk of bias increases as the score reduces.

A review of the scientific literature related to the adverse impact of physical restraint: gaining a clearer understanding of the physiological factors involved in cases of restraint-related death.

Deaths occurring during and/or in close proximity to physical restraint have been attributed to positional asphyxia, a conclusion primarily based on opinion and reviews of case studies. This review sought to identify the current scientific evidence available in regard to the aetiology of adverse events or death occurring during or in close proximity to physical restraint. A systematic search of electronic databases (SPORTDiscus, AMED, CINAHL, MEDLINE, PsycINFO) for papers published in English, between 1980 and 2011, using keywords that related to restraint, restraint position and cardiovascular function resulted in 11 experimental papers being found for review. The term positional asphyxia as a mechanism for sudden death is poorly understood. The literature shows that restraint position has the ability to impede life-maintaining physiological functions, but that the imposed impediment is not uniform across all restraint positions/techniques. Further research is required to ascertain the risks posed by struggling during restraint for more prolonged periods of time and in different positions using varied techniques of restraint. This research should seek to and rank known or future risk factors of adverse events occurring during restraint, seeking to understand the interactions and if present the cumulative effect of these risk factors. Finally, future research should focus on populations other than apparently healthy male adults.

Can surface neuromuscular electrical stimulation of the wrist and hand combined with routine therapy facilitate recovery of arm function in patients with stroke?

OBJECTIVE: To investigate whether treatment with surface neuromuscular electrical stimulation to the wrist extensors improves recovery of arm function in severely disabled patients with stroke. DESIGN: Single blinded randomized controlled trial. SETTING: Acute stroke unit and stroke rehabilitation wards of a university hospital. PARTICIPANTS: Patients with no upper limb function (Action Research Arm Test [ARAT] score 0) (N=90; mean age ± SD, 74±11y; 49% men) were recruited to the study within 6 weeks of stroke. Only 67 participants were alive at the end of the study and data from 66 of these people were analyzed. INTERVENTIONS: Participants were randomized to surface neuromuscular electrical stimulation using surface electrical stimulators for 30 minutes, twice in a working day for 6 weeks in addition to standardized upper limb therapy or just standardized upper limb therapy. MAIN OUTCOME MEASURE: The primary outcome measure was the ARAT score. Assessments were made at baseline and at 6, 12, 24, and 36 weeks after recruitment. RESULTS: There were statistically significant improvements in measures of wrist extensor (mean difference 0.5; 95% confidence interval [CI], 0.0-1.0) and grip strength (mean difference 0.9; 95% CI, 0.1-1.7) over the treatment period. Arm function (ARAT score) was not significantly different between the groups over the treatment period at 6 weeks (mean difference 1.9; 95% CI, -2.9 to 6.8) or over the study period at 36 weeks (mean difference 6.4; 95% CI, -1.8 to 14.7), and the rate of recovery was not significantly different (mean difference 0.7; 95% CI, -0.2 to 1.6). CONCLUSIONS: In patients with severe stroke, with no functional arm movement, electrical stimulation of wrist extensors improves muscle strength for wrist extension and grip, and larger studies are required to study its influence on arm function.

Quantitative measurement of poststroke spasticity and response to treatment with botulinum toxin: a 2-patient case report.

BACKGROUND AND PURPOSE: Spasticity (hypertonicity) is a frequent problem that can develop after stroke and can lead to a number of secondary complications, such as contractures and pain. Consequently, many rehabilitation resources are used in treating the condition and its secondary complications. At present, the clinical assessment of spasticity incorporates descriptive scales of resistance to passive movement, but the use of a neurophysiological measure of muscle activity levels has been advocated. This case report focuses on the diagnosis of spasticity through the use of a neurophysiological measure. CASE DESCRIPTION: . Two individuals who required botulinum toxin treatment for poststroke spasticity were assessed over a course of 20 weeks with both clinical (Modified Ashworth Scale) and neurophysiological (surface electromyography recording of levels of muscle activity) measures of spasticity. Additionally, arm function, arm movement, and pain were measured. The individuals' responses to treatment with botulinum toxin and overall recovery after stroke are described. OUTCOMES: There were discrepancies between the clinical and the neurophysiological measures of spasticity. The clinical measure of spasticity was not effective in consistently identifying the presence of spasticity and, therefore, also was ineffective in documenting the individuals' responses to treatment. The neurophysiological measure was able to identify when muscle activity levels had been reduced, but a reduction in muscle activity levels did not always correspond with a reduction in Modified Ashworth Scale scores. DISCUSSION: The accurate identification of spasticity is important not only for assessment but also for the selection of appropriate treatments after stroke.

Quantifying repeatability of the Wartenberg pendulum test parameters in children with spasticity.

The Wartenberg (pendulum) test is commonly used in a variety of studies involving healthy subjects, patients with CP, stroke patients, and other neurological conditions. There is some evidence that the Wartenberg test may be able to differentiate healthy people from patients with spasticity. The aim of the study was to explore the within-session repeatability of primary outcome measures, i.e. relaxation indices derived from the Wartenberg test when test was performed by single investigator. Patients were lying supine, thigh along the horizontal line. The lower legs were allowed to hang freely over the table edge, and the knee motion in response to leg drop from the horizontal position was measured using motion system VICON with external markers attached to each leg at greater trochanter, lateral knee epicondyle, and lateral malleolus. Data from four consecutive trials were collected at 1 min intervals. The set of relaxation indices and maximum velocity was calculated for each trial. Data of 21 children (42 limbs) who underwent the evaluation due to spasticity problem were analysed. The repeated measure ANOVA test, one way analysis of variance, coefficients of correlation and determination were used to determine the repeatability of the relaxation indices, the association between the indices in time, and influence of the spasticity origin on the variability. The results show that relaxation indices, did not differ between the trails in statistically significant way in our group of patients with spasticity, however they exhibited high within-session variability in the individual patients (16-90%). Therefore the variability of the relaxation indices may restrict the clinical usefulness of the indices to monitor the changes of spasticity over time. Further, our findings do not seem to conform to the earlier reports demonstrating a systematic, time-dependent, change in the relaxation indices when repeated measures were taken within a session. In conclusion, this study demonstrates that although the Wartenberg test is repeatable in groups of patients, it does not provide us with repeatable measures in individual patients, thus if it is to be used as a replacement for other clinical tests of spasticity further investigations are needed to explain the substantial variability of the indices.

Randomized controlled trial to evaluate the effect of surface neuromuscular electrical stimulation to the shoulder after acute stroke.

BACKGROUND AND PURPOSE: Surface neuromuscular electrical stimulation (sNMES) after stroke aims to improve upper limb function and reduce shoulder pain, but current evidence of effectiveness is inconclusive. We have undertaken a randomized controlled trial to evaluate sNMES to the shoulder after acute stroke. METHODS: One hundred seventy-six patients, within 10 days of stroke onset, were randomized to receive sNMES or placebo in addition to stroke unit care. The primary outcome measure was upper limb function measured by the Action Research Arm Test (ARAT) 3 months after stroke. Secondary outcome measures included other measures of upper limb function, upper limb impairment, pain, disability, and global health status. Outcome assessments were blinded. RESULTS: There was no difference in arm function between groups in terms of the primary outcome measure. The median ARAT at 3 months was 50 in the intervention group and 55.5 in the control group (P=0.068). Significant differences were seen at 3 months in favor of the control group for other measures of arm function and impairment: grasp and gross movement subsections of the ARAT, Frenchay Arm Test, and the arm subsection of the Motricity Index. Secondary analysis suggested that these differences were most marked in subjects with severe initial upper limb weakness. CONCLUSIONS: A 4-week program of sNMES to the shoulder after acute stroke does not improve functional outcome and may worsen arm function in severely impaired stroke patients. "Routine" use of sNMES to the proximal affected upper limb after acute stroke cannot be recommended.

The construct validity of a spasticity measurement device for clinical practice: an alternative to the Ashworth scales.

INTRODUCTION: Spasticity is a significant cause of disability in people with an upper motor neurone lesion, but there is a paucity of appropriate outcome measures to evaluate this phenomenon. The aim was to test the construct validity of a clinically relevant, non-invasive measure of spasticity. METHODS: A cross-section study design in which participants with elbow flexor spasticity and capable of providing written informed consent were recruited. RESULTS: Fourteen stroke patients participated (six female and eight male). Median age was 61 years and the median time post stroke was 48 months. Six patients had a MAS grading of '1+', three a grade of '2' and five a grade of '3'. The velocity of the brisk stretch was significantly higher than that of the slow stretch (p < 0.05: median difference, 34 degrees /s: IQR, 20 - 46). Flexor muscle activity during the brisk stretch was significantly higher than that of the slow stretch (p < 0.05: median difference, 2.0 microV; IQR, 0.4 - 8.4). In contrast the RPE was not significantly different between the slow and the fast stretches (p > 0.1: median difference, 0.07 N/deg; IQR, - 0.09 - 0.16). There were no patterns of association between the MAS, elbow flexor muscle activity and RPE. Other important observations, in some patients, were: continuous background muscle activation consistent with descriptions of spastic dystonia; muscle activity at the slow velocity stretch; muscle activation patterns consistent with the clasp-knife phenomenon. CONCLUSIONS: The measurement system was capable of measuring spasticity as defined by Lance (1980; In: Lance et al., editors. Spasticity: disordered motor control. Chicago, IL: Year Book. p 185 - 204). In addition, it enabled various other clinical phenomena associated with spasticity to be measured. Assessing spasticity by measuring changes in resistance to passive movement only may not be sufficient, as the latter is influenced by many factors of which spasticity may only be one. Further work is now required to investigate repeatability and sensitivity.

Biomechanical measurement of post-stroke spasticity.

BACKGROUND: spasticity following stroke is common, but clinical measurement is difficult and inaccurate. The most common measure is the modified Ashworth scale (MAS) which grades resistance to passive movement (RPM), but its validity is unclear. AIM: to assess the validity of the MAS. METHODS: spasticity was clinically graded using MAS and RPM measured biomechanically in the impaired arm of 111 patients following stroke. The biomechanical device measured RPM, applied force, angular displacement, mean velocity, passive range of movement (PROM) and time required. RESULTS: the median age was 72 years, and 66 subjects were male. The clinical grading by MAS was '0' in 15, '1' in 15, '1+' in 14, '2' in 13, '3' in 43 and '4' in 11. There was no difference in RPM among '0', '1', '1+' and '2' (P > 0.1). However, grade'4' was higher than '3' and below (P < 0.05). The force required increased with the increasing MAS while velocity and PROM decreased (P < 0.01). We regrouped the data using the algorithm: no stiffness = '0'; mild = '1' and '1+' and '2'; moderate = '3'; severe = '4'. There was no difference between 'no stiffness' and 'mild ' (P > 0.10), but 'mild' and moderate' as well as 'moderate' and 'severe' were different (P < 0.01). CONCLUSION: the MAS is not a valid ordinal level measure of RPM or spasticity. Objective measurement of RPM is possible in the clinical setting. However, additional measurements of muscle activity (electromyography) will be required to quantify spasticity.

The activity in the three regions of the trapezius under controlled loading conditions--an experimental and modelling study.

BACKGROUND: There is a degree of conflict in the literature regarding the biomechanical role of the three regions of trapezius. It is suggested that some of this may result from a lack of experiments using a well defined loading regime. OBJECTIVES: To study the activity of the three regions of trapezius under controlled load in order to gain further insight into its role in shoulder biomechanics. DESIGN: The emg activity of the three regions of trapezius was studied on five subjects using a specially designed test system which allowed the application of either a uniaxial shrug force or a pure couple in the coronal plane. METHODS: Test rigs were designed and constructed to measure isometric loads applied by shoulder shrugging and isometric pure moments produced in coronal plane abduction and adduction. Surface emg of the three regions of trapezius was performed simultaneously with loading. RESULTS: The activity of upper trapezius was always present but changed little with the type of loading. Middle trapezius was dominant during both shrug and abduction whereas the lower fibres predominated during adduction. CONCLUSIONS: The use of a test system applying defined loading at the shoulder allows the detail analysis of trapezius muscle activity. The reproducible technique can be extended to other shoulder muscles. RELEVANCE: The biomechanics of the shoulder calls for detailed analysis of the activity of all the interacting muscles. This paper describes a techniques which allows study of muscle activity under carefully defined loading.

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 Spearman's 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.