Trunk flexor and extensor muscle performance in chronic stroke patients: a case-control study

Trunk biomechanical changes between the sit-to-stand and stand-to-sit performed at self-selected and fast speeds in stroke survivors

PURPOSE

To compare the trunk biomechanical characteristics between the sit-to-stand and stand-to-sit performed at self-selected and fast speeds in stroke survivors and healthy-matched controls.

METHODS

Thirty individuals (15 stroke survivors and 15 healthy-matched controls) were included. The following biomechanical characteristics were determined: peak of trunk forward flexion and time until the peak of trunk forward flexion, total duration, phase I (sit-to-stand: time spent from the beginning to seat-off; stand-to-sit: time spent from the beginning to seat-on) and II durations (sit-to-stand: time spent from seat-off to the end of the task; stand-to-sit: time spent from the seat-on to the end of the task). Two-way repeated measures ANOVA was used (α = 5%).

RESULTS

The maximum angle of trunk forward flexion and time spent until the maximum angle of trunk forward flexion in both tasks were significantly higher in stroke survivors. For both groups and speeds, phase I duration and peak of trunk forward flexion of the stand-to-sit were significantly higher than that of the sit-to-stand (11.41≤F ≤ 33.60; 0.001 ≤ p ≤ 0.002) and, phase II duration was significantly higher during the sit-to-stand than that of the stand-to-sit (21.27 ≤ F ≤ 65.10; p ≤ 0.001).

CONCLUSIONS

These results confirm specific trunk biomechanical characteristics between sit-to-stand and stand-to-sit in stroke survivors and healthy-matched controls.

Trunk training following stroke

BACKGROUND

Previous systematic reviews and randomised controlled trials have investigated the effect of post-stroke trunk training. Findings suggest that trunk training improves trunk function and activity or the execution of a task or action by an individual. But it is unclear what effect trunk training has on daily life activities, quality of life, and other outcomes.

OBJECTIVES

To assess the effectiveness of trunk training after stroke on activities of daily living (ADL), trunk function, arm-hand function or activity, standing balance, leg function, walking ability, and quality of life when comparing with both dose-matched as non-dose-matched control groups.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register, CENTRAL, MEDLINE, Embase, and five other databases to 25 October 2021. We searched trial registries to identify additional relevant published, unpublished, and ongoing trials. We hand searched the bibliographies of included studies.

SELECTION CRITERIA

We selected randomised controlled trials comparing trunk training versus non-dose-matched or dose-matched control therapy including adults (18 years or older) with either ischaemic or haemorrhagic stroke. Outcome measures of trials included ADL, trunk function, arm-hand function or activity, standing balance, leg function, walking ability, and quality of life.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two main analyses were carried out. The first analysis included trials where the therapy duration of control intervention was non-dose-matched with the therapy duration of the experimental group and the second analysis where there was comparison with a dose-matched control intervention (equal therapy duration in both the control as in the experimental group).  MAIN RESULTS: We included 68 trials with a total of 2585 participants. In the analysis of the non-dose-matched groups (pooling of all trials with different training duration in the experimental as in the control intervention), we could see that trunk training had a positive effect on ADL (standardised mean difference (SMD) 0.96; 95% confidence interval (CI) 0.69 to 1.24; P < 0.001; 5 trials; 283 participants; very low-certainty evidence), trunk function (SMD 1.49, 95% CI 1.26 to 1.71; P < 0.001; 14 trials, 466 participants; very low-certainty evidence), arm-hand function (SMD 0.67, 95% CI 0.19 to 1.15; P = 0.006; 2 trials, 74 participants; low-certainty evidence), arm-hand activity (SMD 0.84, 95% CI 0.009 to 1.59; P = 0.03; 1 trial, 30 participants; very low-certainty evidence), standing balance (SMD 0.57, 95% CI 0.35 to 0.79; P < 0.001; 11 trials, 410 participants; very low-certainty evidence), leg function (SMD 1.10, 95% CI 0.57 to 1.63; P < 0.001; 1 trial, 64 participants; very low-certainty evidence), walking ability (SMD 0.73, 95% CI 0.52 to 0.94; P < 0.001; 11 trials, 383 participants; low-certainty evidence) and quality of life (SMD 0.50, 95% CI 0.11 to 0.89; P = 0.01; 2 trials, 108 participants; low-certainty evidence). Non-dose-matched trunk training led to no difference for the outcome serious adverse events (odds ratio: 7.94, 95% CI 0.16 to 400.89; 6 trials, 201 participants; very low-certainty evidence). In the analysis of the dose-matched groups (pooling of all trials with equal training duration in the experimental as in the control intervention), we saw that trunk training had a positive effect on trunk function (SMD 1.03, 95% CI 0.91 to 1.16; P < 0.001; 36 trials, 1217 participants; very low-certainty evidence), standing balance (SMD 1.00, 95% CI 0.86 to 1.15; P < 0.001; 22 trials, 917 participants; very low-certainty evidence), leg function (SMD 1.57, 95% CI 1.28 to 1.87; P < 0.001; 4 trials, 254 participants; very low-certainty evidence), walking ability (SMD 0.69, 95% CI 0.51 to 0.87; P < 0.001; 19 trials, 535 participants; low-certainty evidence) and quality of life (SMD 0.70, 95% CI 0.29 to 1.11; P < 0.001; 2 trials, 111 participants; low-certainty evidence), but not for ADL (SMD 0.10; 95% confidence interval (CI) -0.17 to 0.37; P = 0.48; 9 trials; 229 participants; very low-certainty evidence), arm-hand function (SMD 0.76, 95% CI -0.18 to 1.70; P = 0.11; 1 trial, 19 participants; low-certainty evidence), arm-hand activity (SMD 0.17, 95% CI -0.21 to 0.56; P = 0.38; 3 trials, 112 participants; very low-certainty evidence). Trunk training also led to no difference for the outcome serious adverse events (odds ratio (OR): 7.39, 95% CI 0.15 to 372.38; 10 trials, 381 participants; very low-certainty evidence). Time post stroke led to a significant subgroup difference for standing balance (P < 0.001) in non-dose-matched therapy. In non-dose-matched therapy, different trunk therapy approaches had a significant effect on ADL (< 0.001), trunk function (P < 0.001) and standing balance (< 0.001). When participants received dose-matched therapy, analysis of subgroup differences showed that the trunk therapy approach had a significant effect on ADL (P = 0.001), trunk function (P < 0.001), arm-hand activity (P < 0.001), standing balance (P = 0.002), and leg function (P = 0.002). Also for dose-matched therapy, subgroup analysis for time post stroke resulted in a significant difference for the outcomes standing balance (P < 0.001), walking ability (P = 0.003) and leg function (P < 0.001), time post stroke significantly modified the effect of intervention.  Core-stability trunk (15 trials), selective-trunk (14 trials) and unstable-trunk (16 trials) training approaches were mostly applied in the included trials.

AUTHORS' CONCLUSIONS

There is evidence to suggest that trunk training as part of rehabilitation improves ADL, trunk function, standing balance, walking ability, upper and lower limb function, and quality of life in people after stroke. Core-stability, selective-, and unstable-trunk training were the trunk training approaches mostly applied in the included trials. When considering only trials with a low risk of bias, results were mostly confirmed, with very low to moderate certainty, depending on the outcome.

Effect of Core Exercises on Motor Function Recovery in Stroke Survivors with Very Severe Motor Impairment

Paresis of the upper and lower limbs is a typical issue in stroke survivors. This study aims to determine whether core exercises help stroke survivors with very severe motor impairment recover their motor function. This study employed a within-subjects design. Eleven hemiparetic stroke patients with very severe motor impairment (FMA score < 35) and ages ranging from 24 to 52 years old were enrolled in this study. All participants engaged in supervised core exercise training twice a week for 12 weeks. The main outcome measures were Fugl-Meyer Assessment Lower Extremity (FMA-LE) and Fugl-Meyer Assessment Upper Extremity (FMA-UE), which were measured before training and at intervals of four weeks during training. Repeated measures ANOVA was used to analyze the effect of core exercises on motor function performance and lower extremity motor function and upper extremity motor function recovery. There were significant differences in the mean scores for motor function performance, lower extremity motor function, and upper extremity motor function throughout the four time points. A post-hoc pairwise comparison using the Bonferroni correction revealed that mean scores significantly increased and were statistically different between the initial assessment and follow-up assessments four, eight, and twelve weeks later. This study suggests that 12 weeks of core exercise training is effective for improving motor function recovery in patients with very severe motor impairment.

Telerehabilitation for balance rehabilitation in the subacute stage of stroke: A pilot controlled trial

BACKGROUND

Telerehabilitation has been proposed as an effective strategy to deliver post-stroke specific exercise.

OBJECTIVE

To assess the effectiveness and feasibility of core stability exercises guided by a telerehabilitation App after hospital discharge.

METHODS

Extension of a prospective controlled trial. Subacute stage stroke survivors were included at the time of hospital discharge where they had participated in a previous 5-week randomized controlled trial comparing conventional physiotherapy versus core stability exercises. After discharge, patients from the experimental group were offered access to telerehabilitation to perform core stability exercises at home (AppG), while those from the control group were subject to usual care (CG). The Spanish-version of the Trunk Impairment Scale 2.0 (S-TIS 2.0), Function in Sitting Test (S-FIST), Berg Balance Scale (BBS), Spanish-version of Postural Assessment for Stroke Patients (S-PASS), the number of falls, Brunel Balance Assessment (BBA) and Gait were assessed before and after 3 months intervention.

RESULTS

A total of 49 subjects were recruited. AppG showed greater improvement in balance in both sitting and standing position and gait compared with CG, although no statistically significant differences were obtained.

CONCLUSION

Core stability exercises Telerehabilitation as a home-based guide appears to improve balance in post-stroke stage. Future studies are necessary to confirm the effects as well as identifying strategies to increase telerehabilitation adherence.

Kinematic Analysis of 360° Turning in Stroke Survivors Using Wearable Motion Sensors

Background: A stroke often bequeaths surviving patients with impaired neuromusculoskeletal systems subjecting them to increased risk of injury (e.g., due to falls) even during activities of daily living. The risk of injuries to such individuals can be related to alterations in their movement. Using inertial sensors to record the digital biomarkers during turning could reveal the relevant turning alterations. Objectives: In this study, movement alterations in stroke survivors (SS) were studied and compared to healthy individuals (HI) in the entire turning task due to its requirement of synergistic application of multiple bodily systems. Methods: The motion of 28 participants (14 SS, 14 HI) during turning was captured using a set of four Inertial Measurement Units, placed on their sternum, sacrum, and both shanks. The motion signals were segmented using the temporal and spatial segmentation of the data from the leading and trailing shanks. Several kinematic parameters, including the range of motion and angular velocity of the four body segments, turning time, the number of cycles involved in the turning task, and portion of the stance phase while turning, were extracted for each participant. Results: The results of temporal processing of the data and comparison between the SS and HI showed that SS had more cycles involved in turning, turn duration, stance phase, range of motion in flexion–extension, and lateral bending for sternum and sacrum (p-value < 0.035). However, HI exhibited larger angular velocity in flexion–extension for all four segments. The results of the spatial processing, in agreement with the prior method, showed no difference between the range of motion in flexion–extension of both shanks (p-value > 0.08). However, it revealed that the angular velocity of the shanks of leading and trailing legs in the direction of turn was more extensive in the HI (p-value < 0.01). Conclusions: The changes in upper/lower body segments of SS could be adequately identified and quantified by IMU sensors. The identified kinematic changes in SS, such as the lower flexion–extension angular velocity of the four body segments and larger lateral bending range of motion in sternum and sacrum compared to HI in turning, could be due to the lack of proper core stability and effect of turning on vestibular system of the participants. This research could facilitate the development of a targeted and efficient rehabilitation program focusing on the affected aspects of turning movement for the stroke community.

Core Stability Exercises Yield Multiple Benefits for Patients with Chronic Stroke - Randomized Controlled Trial

OBJECTIVE

This study examines the effect of core stability exercises on trunk control, core muscle strength, standing weight-bearing symmetry and balance confidence of people with chronic stroke.

DESIGN

This was an assessor-blinded randomized controlled trial involving 84 ambulatory patients with middle cerebral artery stroke, randomly assigned to three training groups. Two experimental groups practiced core stability exercises either on stable or unstable support surfaces. In contrast, the control group received standard physiotherapy. All the participants an hour-long training session a day, thrice a week over a six-week duration, and followed-up after 12 months. Trunk Impairment Scale, core muscle strength, weight-bearing asymmetry in standing and Activities-specific Balance Confidence scale were the outcome measures.

RESULTS

Compared to the control group, the two experimental groups demonstrated a significant improvement on all the outcome measures from baseline to post-training and from baseline to 12-month follow-up (P < 0.001). The two experimental groups demonstrated no significant difference between them on all the measures (P > 0.05).

CONCLUSION

Core stability exercises on stable and unstable support surfaces are equally beneficial in improving trunk control, core muscle strength, standing weight-bearing symmetry and balance confidence of ambulatory patients with chronic stroke than the standard physiotherapy.

Association between trunk core muscle thickness and functional ability in subacute hemiplegic stroke patients: an exploratory cross-sectional study

BACK GROUND

Balance impairment could occur due to weakness of the core muscles in stroke patients.

OBJECTIVE

To investigate the association between functional ability, including trunk balance and core muscle thickness using ultrasonography in subacute hemiplegic stroke patients.

METHODS

The muscle thickness of the anterior and posterior trunk muscles was measured using ultrasonography. For the evaluation of trunk balance, trunk impairment scale and Berg balance scale (BBS) were used. The functional ambulatory scale (FAS), timed up-and-go test, 10 m gait velocity, functional reach (FR), and functional independence measure were also assessed for functional ability.

RESULTS

Overall, 41 patients with subacute hemiplegic stroke were included. Partial correlation analysis showed that posterior trunk muscle thickness was significantly correlated with BBS, FAS, and FR. As for the paralytic side, the posterior trunk muscle thickness of both paretic and nonparetic sides presented a significant relationship with BBS, FAS, and FR. The quadratus lumborum (QL) thickness of both sides showed a significant relationship with BBS, FAS, and FR.

CONCLUSIONS

The thickness of the posterior trunk muscles, especially the QL, on both the paretic and nonparetic sides, was significantly related with the functional ability after stroke. The exercise program of core posterior trunk muscles closely related with functional ability would be helpful to improve trunk balance and ambulatory function in subacute stroke patients.

Measurement of trunk muscle strength after stroke: An integrative review

BACKGROUND

Research examining the measurement of trunk muscle strength after stroke is limited and diverse. This review, therefore, was undertaken to summarize research addressing what is known about measurements of trunk muscle strength after stroke.

METHODS

Potentially relevant research was identified via 3 electronic database searches and a hand search. The research was examined for information on patients, measurement procedures and study findings. Findings regarding measurement properties (ie, validity, reliability, and responsiveness) were of particular interest.

RESULTS

Searches identified 260 potentially relevant articles of which 28 met inclusion and exclusion criteria. Research involving diverse populations and measurement procedures demonstrates that trunk muscle strength is impaired after stroke. Many studies show that measurements of trunk muscle strength have known-groups/conditions and convergent validity with balance and performance of functional activities. The literature also supports the reliability of measurements of trunk strength after stroke. Little is known regarding the responsiveness of the measurements.

CONCLUSIONS

Trunk strength is commonly impaired after stroke. As weakness of the trunk muscles can affect balance and function, it may warrant routine measurement.

The Influence of Nordic Walking on Isokinetic Trunk Muscle Endurance and Sagittal Spinal Curvatures in Women after Breast Cancer Treatment: Age-Specific Indicators

Nordic walking (NW) is a popular form of rehabilitation. NW improves psychophysical condition in breast cancer (BC) survivors. This study aimed to analyze the effects of NW on functional and postural changes of the trunk in women of different ages after BC. We hypothesized that an age relationship would be found. BC survivors (n = 39) were stratified by age as “middle- aged” (45–59 years) or “older” (60–75 years), then randomly allocated to the training intervention. A study group (SG, n = 19) participated in NW and a control group (CG, n = 20) performed general gymnastics. The sagittal spinal curvatures and isokinetic trunk muscle endurance were recorded at two time points, pre- and post-training intervention. Significant within NW group changes (p < 0.05) were found for the total work (TW) and average power (AP) of trunk flexors and extensors and the upper thoracic angle in middle-aged women. In older Nordic walkers, significant increases in TW and AP of the trunk flexor muscles were observed, with a negative increase in the trunk inclination angle. In CG, no significant functional or postural changes were observed in response to general gymnastics. NW improved both functional and postural changes in middle-aged women. This study identified the limitations of NW training in older women.

A Method for Quantifying Trunk Motor Control During Reaching in Individuals Post Hemiparetic Stroke

After a hemiparetic stroke, the contralesional upper limb is left with significant motor impairments including: weakness, spasticity, and abnormal joint torque patterns resulting in the flexion synergy (i.e. abnormal coupling between shoulder abduction and elbow/wrist and finger flexion). These impairments, and in particular the flexion synergy, limit ability to reach to the full extent of their limb workspace. Motor control of the trunk is also altered post stroke, with compromised ability to stabilize the trunk and excessive trunk movement during reaching, abnormal isometric torque coupling patterns in the transverse and sagittal planes and weakness. These motor impairments in both trunk and arm limit their ability to perform activities of daily living. While the effect of stroke on reaching has been studied extensively, less is known about the impact of deficits in trunk motor control on reaching ability and the impact of the flexion synergy on trunk postural control. Methods for investigating altered trunk control, specifically during a reach when concurrent loads that elicit the flexion synergy are imposed on the limb and trunk, are limited. Specifically, trunk deficits have yet to be studied in the context of the flexion synergy whereby loads imposed on the arm to elicit shoulder abduction have a negative impact on reaching and potentially on trunk posture. In order to address this gap, we developed a system that integrates a robotic device to simulate varied reaching environments, surface electromyography to measure primary trunk and arm muscle activity, and a two-camera motion capture system that uses reflective markers to measure trunk and arm movement. Feasibility and usability of the system was established during evaluation of reaching ability with varying levels of shoulder abduction loads while the trunk is either restrained or unrestrained in two participants with stroke and a healthy control.Clinical Relevance- The system presented here is capable of monitoring changes in trunk postural control after a hemiparetic stroke during a reaching task as a first step in furthering our understanding of changes in trunk motor control during reaching with the goal of developing more targeted and effective interventions for stroke rehabilitation.

Isokinetic Analysis of Trunk Muscles in Stroke Patients and its Association with Functional Parameters

OBJECTIVE

The purpose of our study is to investigate the association of balance, motor and functional development parameters with trunk muscles via isokinetic analysis in stroke patients due to cerebrovascular event.

METHODS

The study included 91 stroke patients and 28 healthy controls. Brunnstroom staging (BS) for motor functions, functional independence measurement (FIM) and Barthel index (BI) for disability, Berg balance scale (BBS) balance test for balance, Rivermead motor evaluation (RMA) for mobility, and mini-mental test (MMT) for cognitive function were used. Strength and proprioception measurements of patients and controls' trunk extensor and flexor muscles were evaluated via exercise system and isokinetic test.

RESULTS

A strong positive correlation was found between FIM total score and lower-extremity Brunnstrom staging (p < 0.001). A strong positive correlation was found between trunk control test (TCT), and FIM total scores (p < 0.001, r = 0.892), BI (p < 0.001, r = 0.799) and BBS (p = 0.01, r = 0.885). Isokinetic muscle strength values of controls were found statistically significantly higher than those in patients with stroke (p < 0.001). Trunk control and proprioception were poor in patients with stroke compared to the control group (p <0.001). Trunk muscles performance measures were significantly associated with balance and functional parameters. However, no significant relationship was found between the angular values of trunk muscle proprioception and clinical parameters in patients with stroke.

CONCLUSIONS

In stroke patients, trunk muscles were weak and trunk proprioception was impaired. So, inserting exercise programs to strengthen trunk muscles and improve trunk proprioception through isokinetic dynamometers or conventional methods into the rehabilitation programs of patients with muscle weakness and proprioception disorder may provide a better functional development.

Five-repetition sit-to-Stand test among patients post-stroke and healthy-matched controls: the use of different chair types and number of trials

Background: In 2018, the American Physical Therapy Association (APTA) published a clinical guideline for adults with neurological conditions, which included recommendations for the Five-Repetition Sit-to-Stand test (5STSt). According to the APTA, a standard-height chair should be used, but there is no recommendation regarding seat depth. In addition, the APTA recommended the use of one trial of the test, based on expert opinion.Objectives: (1) Compare the 5STSt scores of patients post-stroke and healthy-matched controls using two types of chairs (one standardized and one adjusted to the individual's anthropometric characteristics); and (2) Verify whether different numbers of trial affect the 5STSt scores.Methods: Eighteen patients post-stroke and 18 healthy-matched controls performed three trials of the 5STSt for each type of chair. ANOVA was used for analysis (α = 0.05).Results: No significant interaction between groups and chairs was found. Patients post-stroke showed worsened performances in 5STSt when using both chairs compared to the healthy controls (p = .001). In both groups, the 5STSt scores were lower when using a standardized chair than an adjusted chair (p < .003) and different numbers of trials provided similar 5STSt scores (0.44 ≤ p ≤ 0.98).Conclusion: The 5STSt scores were affected by the physical characteristics of the chair, and an adjusted chair should be used. The APTA recommendation for one trial of the 5STSt is supported by the present results.

Post-stroke shoulder pain subtypes classifying criteria: towards a more specific assessment and improved physical therapeutic care

BACKGROUND

Post-stroke Shoulder Pain (PSSP) is a common stroke-related syndrome that prolongs hospitalization and diminishes quality of life. PSSP studies were unsuccessful in clarifying pathophysiological mechanisms. Therefore, cohort's studies with greater variety of the sample and larger follow-up period could provide additional clinical data and may improve medical care.

OBJECTIVE

To classify people with PSSP and identify intergroup clinical differences, providing additional data useful for therapeutic care planning.

METHODS

One thousand individuals with stroke were selected from all levels of one health Area and followed up during one year. Demographic data, stroke clinical characteristics, stroke-related symptoms and rehabilitation parameters were collected. The shoulder muscle impairment was used to group participants into three clinical profiles: severe muscular impairment, moderate muscular impairment and low muscular impairment groups.

RESULTS

A total of 119 individuals were diagnosed with PSSP. The suggested classification criteria showed two groups that differed significantly in relation to the onset and duration of PSSP, presence of sensory and speech impairment, and spasticity. The outcomes did not firmly support the existence of a third suggested PSSP subtype.

CONCLUSIONS

PSSP may vary in onset, clinical manifestations, severity and syndrome duration. These results highlight the course of different clinical profiles and require multidisciplinary management approaches.

Strength of the lower limb and trunk muscles is associated with gait speed in individuals with sub-acute stroke: a cross-sectional study

OBJECTIVES

To investigate the association between measures of strength of the lower limb and trunk muscles and gait speed and to identify the muscle group that would best predict gait speed in individuals with sub-acute stroke.

METHODS

Using a cross-sectional observational study design, forty-four individuals with sub-acute stroke (62 years, SD=14; 4 months, SD=1 post-stroke) were assessed. The evaluations were performed at a university laboratory, participants' homes, or community-based settings. Bilateral maximum isometric strength (hip, knee, and ankle flexors/extensors, hip abductors, trunk flexors/extensors, and trunk lateral flexors and rotators) was measured using a portable dynamometer. Comfortable and maximum gait speeds were measured using the 10-m walk test.

RESULTS

Weak to moderate associations were found between measures of strength of the lower limb muscles and comfortable (0.36≤r≤0.53; p<0.05) and maximum (0.37≤r≤0.59; p<0.05) gait speeds, except for the non-paretic knee flexors and comfortable gait speed (p=0.06). Weak to moderate associations were also found between measures of strength of the trunk muscles and comfortable (0.39≤r≤0.50; p<0.05) and maximum (0.39≤r≤0.61; p<0.05) gait speeds. Stepwise multiple regression analyses revealed that the non-paretic dorsiflexors and the left lateral trunk flexors explained 29% and 42% of the variance in the maximum and comfortable gait speeds, respectively.

CONCLUSIONS

The strength of the lower limb and trunk muscles was positively associated with comfortable and maximum gait speeds. The muscle strength of the non-paretic dorsiflexors and the left lateral trunk flexors might have a role to play in determining comfortable and maximum gait speeds of individuals with sub-acute stroke.

Knee extensor muscles strength indicates global lower-limb strength in individuals who have suffered a stroke: A cross-sectional study

OBJECTIVES

This study had three aims: (1) to evaluate the relationships between the paretic knee extensor muscle strength and global lower-limb strength in individuals who had suffered a sub-acute/chronic stroke, (2) to determine whether global lower-limb strength, sex, body mass index, or age could predict knee extensor muscle strength, and 3) to investigate whether the results obtained via a Modified Sphygmomanometer Test (MST) would be similar to those obtained using a hand-held dynamometer.

METHODS

This was a cross-sectional study, performed at a research laboratory, at participants' homes, or at outpatient clinics. Forty-two individuals with a sub-acute stroke and 45 individuals with a chronic stroke participated. Maximum isometric strength of the paretic lower-limb muscles (i.e. hip, knee, and ankle flexors/extensors, hip abductors) was measured using the MST and a hand-held dynamometer.

RESULTS

Significant and high correlation coefficients were found between knee extensor muscle strength and global lower-limb strength as measured by the combined strength values of 6 lower limb muscle groups in individuals with sub-acute (0.81≤r≤0.88; p<0.05) and chronic (0.82≤r≤0.85; p<0.05) stroke. Step-wise multiple regression analysis revealed that only global lower-limb strength was retained in the model and accounted for 66-78% and 67-72% (p<0.001) of the variance in knee extensor muscle strength at the sub-acute and chronic phases post-stroke, respectively. The results obtained via the MST were similar to those obtained using the hand-held dynamometer.

CONCLUSION

Paretic knee extensor muscles strength, assessed using a MST or a hand-held dynamometer, indicates global lower-limb strength in individuals with a sub-acute or chronic stroke.