Ultrasound Assessment of Spastic Muscles in Ambulatory Chronic Stroke Survivors Reveals Function-Dependent Changes.

OBJECTIVE: To correlate ultrasound characteristics of spastic muscles with clinical and functional measurements in chronic stroke survivors. METHODS: Ultrasound assessment and clinical and functional assessments were performed in 28 ambulatory stroke survivors (12 females, mean age 57.8 ± 11.8 years, 76 ± 45 months after stroke). RESULTS: Muscle thickness in the affected side was decreased compared with the contralateral side (p < 0.001). The decrease was more evident in the upper limb muscles. On the affected side, the modified Heckmatt scale score was lowest (closer to normal) in the rectus femoris (RF) muscle compared with other muscles (biceps brachii (BB), flexor carpi ulnaris (FCU) and medial gastrocnemius (MG)). Muscle thickness and echogenicity of spastic muscles did not correlate with spasticity, as measured with the modified Ashworth scale (MAS), Fugl-Meyer motor assessment scores, age, or time since stroke. There was a significant negative correlation between grip strength and percentage decrease in muscle thickness for the spastic FCU muscle (r = -0.49, p = 0.008). RF muscle thickness correlated with ambulatory function (Timed Up and Go test (r = 0.44, p = 0.021) and 6-metre walk test (r = 0.41, p = 0.032)). There was no significant correlation between echogenicity and functional assessments Conclusion: Ambulatory chronic stroke survivors had function-dependent changes in muscle thickness on the affected side. Muscle thickness and echogenicity of spastic muscles did not correlate with spasticity, Fugl-Meyer motor assessment scores, age, or time since stroke.

Ultrasound Elastography in the Assessment of the Stiffness of Spastic Muscles: A Systematic Review.

The incidence of muscle spasticity is high in patients with diseases of the central nervous system. This condition leads to significant limitations in movement and impaired functional capacities. Muscle spasticity manifests as changes in the mechanical properties of the muscles. This muscle disorder is generally assessed using qualitative methods, whose validity, reliability and sensitivity are questionable. In recent years, ultrasound elastography (USE) has been used as a non-invasive technique for characterizing the stress response and mechanical properties of individual muscles in the evaluation of spasticity. This article presents a systematic review of the USE techniques, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) declaration guidelines, used for the evaluation of muscle stiffness caused by spasticity. The articles selected in this study were evaluated using the Quality Appraisal of Diagnostic Reliability (QAREL) tool. Mainly, studies on the assessment of spasticity involving the evaluation of muscle stiffness with USE techniques (i.e., shear-wave elastography [SWE] or compression elastography [CE]) were selected. Then, common topics related to the assessment of spastic muscles and the statistical results of these studies were classified. Of 21 articles, nine used only CE, 10 used only SWE and two used both techniques. In the studies, statistically significant differences were observed in the measurements of muscle stiffness between the paretic and non-paretic sides as well as between patients and healthy patients. The clinical measurements obtained, devices used and assessment and probe positions for both techniques were discussed. The most frequently studied muscles were the biceps (n = 7) and gastrocnemius (n = 11). On applying the QAREL tool, we found that only two studies showed compliance at 80%-90%, seven studies at 50%-70% and the remaining 12 at 10%-40%. The results showed that USE techniques have limitations in spasticity assessment, such as subjectivity because of the lack of standardized protocols. A deficit of studies on intra-operator and inter-operator measurements indicates that this technique is not yet mature for spasticity diagnosis, although it is a promising diagnostic tool for designing treatment plans and monitoring the effectiveness of therapeutic modalities.

Analysis of Machine Learning-Based Assessment for Elbow Spasticity Using Inertial Sensors.

Spasticity is a frequently observed symptom in patients with neurological impairments. Spastic movements of their upper and lower limbs are periodically measured to evaluate functional outcomes of physical rehabilitation, and they are quantified by clinical outcome measures such as the modified Ashworth scale (MAS). This study proposes a method to determine the severity of elbow spasticity, by analyzing the acceleration and rotation attributes collected from the elbow of the affected side of patients and machine-learning algorithms to classify the degree of spastic movement; this approach is comparable to assigning an MAS score. We collected inertial data from participants using a wearable device incorporating inertial measurement units during a passive stretch test. Machine-learning algorithms-including decision tree, random forests (RFs), support vector machine, linear discriminant analysis, and multilayer perceptrons-were evaluated in combinations of two segmentation techniques and feature sets. A RF performed well, achieving up to 95.4% accuracy. This work not only successfully demonstrates how wearable technology and machine learning can be used to generate a clinically meaningful index but also offers rehabilitation patients an opportunity to monitor the degree of spasticity, even in nonhealthcare institutions where the help of clinical professionals is unavailable.

Intrathecal Baclofen Therapy in Patients With Multiple Sclerosis: Improved Outcomes and Reduced Costs Through Identification of Catheter Malfunction.

INTRODUCTION: Two patients previously implanted with intrathecal Baclofen (ITB) pumps for management of intractable spasticity due to multiple sclerosis (MS) were referred to our center for ongoing management of their spasticity. Initial evaluation of these patients revealed high levels of spasticity in the presence of ITB doses 10 times the average daily dose of our other MS patients. CLINICAL FACTS: High doses of ITB required frequent clinical visits and result in high drug and procedure costs. Both patients' daily doses were greater than 1000 mcg/day resulting in clinical visits every 1-2 months with drug and procedure costs ranging from 16 to 23 thousand dollars annually based on Medicare national average pricing for physician's office. Of the 59 MS patients receiving ITB therapy at our institution, the mean, median, and mode daily doses for ITB are 184, 115, and 159 mcg/day, respectively. The high ITB doses in these patients and poor spasticity control raised suspicion for pump/catheter malfunction and prompted immediate troubleshooting. FINDINGS: One patient's catheter was found to be disconnected from the pump and the other's catheter tip was outside the intrathecal space. In both cases, the patients were not receiving the therapy. After pump/catheter replacement, both patients received excellent clinical benefits from ITB at significantly lower daily doses. This reduction in dose resulted in decreased frequency of medication refills (twice annually) which resulted in decreased cost of care (12-19 thousand dollars savings annually per patient). DISCUSSION: These cases illustrate the need for early ITB pump troubleshooting to identify catheter problems, improve efficacy, and avoid unnecessary healthcare costs.

Quantitative assessment of muscular stiffness in children with cerebral palsy using acoustic radiation force impulse (ARFI) ultrasound elastography.

PURPOSE: To evaluate the feasibility of quantitative analysis of muscle stiffness in the medial gastrocnemius muscle (GCM) by acoustic radiation force impulse (ARFI) ultrasound elastography in children with spastic cerebral palsy (CP). METHODS: Seventeen children with spastic CP and 25 healthy children participated in the study between the years 2016-2017. The medial GCM in the CP group was assessed using the Modified Ashworth Scale (MAS) by a physiatrist. ARFI was used to measure the shear-wave velocities (SWVs) of the medial GCM. The mean SWV value for each MAS score was calculated and used for statistics. RESULTS: The mean SWV values of the medial GCM in the CP and healthy groups were 3.17 ± 0.81 m/s (mean ± SD) and 1.45 ± 0.25 m/s (mean ± SD), respectively. The SWV of the medial GCM significantly increased in the CP patients when compared with controls (p < 0.001). In addition, the SWV values were correlated with the MAS scores (p < 0.001). The interobserver agreement expressed as the interclass correlation coefficient was 0.65 (95% CI 0.33-0.84, p < 0.001). CONCLUSIONS: ARFI imaging demonstrated a difference in muscle stiffness in the medial GCM between the CP and healthy groups. This method is a feasible imaging modality for the noninvasive assessment of contracting muscles in children with CP.

Quantitative assessment of muscle stiffness with acoustic radiation force impulse elastography after botulinum toxin A injection in children with cerebral palsy.

PURPOSE: Our objective in this study was to assess the changes in medial gastrocnemius muscle (GCM) stiffness after botulinum toxin A (BTA) injection in children with cerebral palsy (CP) by using acoustic radiation force impulse (ARFI) elastography and to research the usability of this technique in clinical practice. MATERIALS AND METHODS: Twenty-four spastic lower extremities of 12 children with CP were assessed. BTA injection treatment was applied to the medial GCM. Muscle stiffness was measured with the ARFI technique before the procedure and a month after the procedure. The patients were assessed with the modified Ashworth scale (MAS) in the physiotherapy department at about the same time. Shear wave velocity (SWV) values and MAS scores before and after the treatment were compared. RESULTS: Mean SWV values were measured as 3.20 ± 0.14 m/s before BTA and as 2.45 ± 0.21 m/s after BTA, and the difference between them was found to be statistically significant (p < 0.001). Mean MAS score (2.33 ± 0.70) after BTA decreased significantly when compared to the score before BTA (2.96 ± 0.62) (p = 0.001). SWV values positively correlated with MAS scores (ρ = 0.578, p = 0.003). The interobserver agreement expressed as interclass correlation coefficient (ICC) was 0.65 (95% CI 0.33-0.84, p < 0.001). CONCLUSION: ARFI elastography for identifying structural changes that occur in the spastic muscle after BTA injection in children with CP can yield more valuable information with combined use of MAS.

Assessment of forearm muscle spasticity with sonoelastography in patients with stroke.

OBJECTIVE: The aim of the study was to investigate the feasibility of sonoelastography to show muscle stiffness in post-stroke spasticity, and the relationship between sonoelastography findings and clinical spasticity scores in the spastic forearm muscles. METHODS: This study was carried out in a university rehabilitation centre. 23 patients with stroke with forearm muscle spasticity (≥1+ using the Modified Ashworth scale score and ≥1 using the Tardieu scale) were included. Sonoelastography parameters (elasticity index and elasticity ratio) were measured from the flexor digitorum superficialis, flexor digitorum profundus, flexor carpi radialis and flexor carpi ulnaris muscles on the affected and unaffected sides. RESULTS: Both elasticity index and elasticity ratio of the wrist and finger flexors on the hemiplegic side were significantly increased compared with those on the healthy side (p < 0.05). The Tardieu angle of finger flexors was negatively correlated with the elasticity index and elasticity ratio measured in the spastic flexor digitorum profundus (r = -0.418 and r = -0.469, respectively). Tardieu angle of finger flexors was negatively correlated with the elasticity index measured in the spastic flexor digitorum superficialis (r = -0.435). There was no correlation between other parameters. CONCLUSION: Sonoelastography may provide objective assessment of spasticity both in diagnosis and follow-up. To strengthen this prediction, further studies are necessary. Advances in knowledge: The results of this study represent that sonoelastography is a promising evaluation method for forearm muscle spasticity.

Bone strength in multiple sclerosis: cortical midtibial speed-of-sound assessment.

It has been previously suggested that multiple sclerosis (MS) patients are at increased risk for osteoporosis due to reduced mobility, decreased exposure to sunlight and recurrent steroid treatment. In order to systematically evaluate bone strength we assessed 256 MS patients (171 females, 75 males) through quantitative ultrasound measurement of cortical bone. Tibial speed of sound (SOS, m/sec) was measured at midpoint of the tibial shaft using a Soundscan 2000 (Myriad Ultrasound Systems, Rehovot, Israel) and results were compared to age- and gender-matched population norms. T-score distribution in male MS patients was similar to normal population. In contrast, for female MS patients T-score distribution was significantly different from population norms, reflected by increased SOS in 30.4% (T-score intervals 1-2 and >2 above normal values; P=0.001), compared with 7.4% in controls. These findings held true for both female patients younger and older than 45 years of age. Increased neurological disability and specifically motor involvement were more frequent in female patients with increased SOS (P<0.05). Bone strength was preserved in MS patients. In a subgroup of female patients increased SOS was conceivably related to spasticity.