The effect of foot position and chair height on the asymmetry of vertical forces during sit-to-stand and stand-to-sit tasks in individuals with hemiparesis

BACKGROUND

The asymmetrical motor pattern of persons with hemiparesis influences the performance of activities that require interactions between the two sides of the body.

METHODS

Twelve subjects with a chronic hemiparesis were asked to stand up and sit down at their natural speed in the following foot positions: (1) spontaneous; (2) symmetrical; (3) asymmetrical with the affected foot placed backward; and (4) asymmetrical with the unaffected foot placed backward. Forces were recorded under each foot using two force plates and under each thigh with an instrumented chair. Each foot position was tested at two chair heights corresponding to 100% and 120% of leg length. For each condition, the duration and the asymmetry of loading expressed by the vertical forces were calculated for four different events: onset, transition (forces under feet and thighs), seat-off or seat-on and at the end of the task.

FINDINGS

The time to execute the tasks ranged from 2.31 s to 3.69 s with higher values observed for the stand-to-sit task than for the sit-to-stand task. Overall, the asymmetry of vertical forces was greatest in the middle part of the tasks and was not influenced by the chair height. When the subjects were still in contact with the seat, the loading asymmetry originated from a difference between sides at both the thigh and the foot. The asymmetrical foot position with the affected foot backward promoted loading on the affected side during both tasks. Interpretation. This study shows that loading asymmetry was present before seat-off and after seat-on in sit-to-stand and stand-to-sit tasks, respectively. It shows that positioning the affected foot behind reduces the asymmetry whereas positioning the unaffected foot behind increases the asymmetry. Foot position should be taken into consideration when clinicians assess or train for these mobility tasks.

Side difference in the hip and knee joint moments during sit-to-stand and stand-to-sit tasks in individuals with hemiparesis

BACKGROUND

No study has reported the differences between sides in the net muscular moment of lower limbs of subjects with hemiparesis during sit-to-stand and stand-to-sit tasks in various foot positions. Moreover, the asymmetry of lower-joint moments has not yet been related to muscular weakness of the lower limbs in this population.

METHODS

A convenience sample of 12 individuals (mean age (standard deviation): 49.7 (9.0) years) with chronic hemiparesis due to stroke were asked to stand up and sit down at their natural speed in four foot positions. The joint moments at the hip and knee on both sides during the tasks were estimated with an inverse dynamic approach while the dynamic concentric strength in extension at the hip and knee was assessed with a Biodex dynamometric system. Statistical analyses (paired t-tests and ANOVAs) were used to assess the effects of sides and foot position factor on the asymmetry in the hip and knee joint moments. The level of association between muscle weakness and the asymmetry in the joint moments was quantified with Pearson correlation coefficients (r).

FINDINGS

At the knee, the extensor moments were significantly lower on the affected side (P<0.05) and were affected by the foot position. At the hip, the moments were not significantly different between sides and were slightly modified by the foot positions. There were also strong correlations (0.70<r<0.89; P<0.05, for symmetrical foot position) between the asymmetry in knee extensor moments and the asymmetry in strength. No relation was established at the hip.

INTERPRETATION

The sit-to-stand and stand-to-sit tasks are characterized by a marked asymmetry in the knee extensor moments, which is associated with knee extensor weakness.

Effects of Repeated Distension Arthrographies Combined with a Home Exercise Program Among Adults with Idiopathic Adhesive Capsulitis of the Shoulder

OBJECTIVE

The purpose of this study was to measure the effect of repeated distension arthrographies combined with a home exercise program on impairments and disability of the upper limb in subjects with adhesive capsulitis of the shoulder.

DESIGN

A total of 15 subjects with idiopathic adhesive capsulitis participated in the study. Intervention consisted of three distension arthrographies with steroid, done at 3-wk intervals, and a home exercise program. The repeated-measures design included five clinical evaluations with disability, pain, range of motion, and pain-free static strength outcomes. Two evaluations done before the first arthrography verified the stability of the condition.

RESULTS

There was a significant improvement of all outcomes at the end of intervention. The greatest effects occurred after the first distension arthrography. After the second, less marked, albeit significant, changes were observed in three motions of the shoulder and in the pain level. After the third distension arthrography, very small changes were noted. A comparison between sides revealed incomplete recovery of the range of motion on the affected side.

CONCLUSIONS

These findings showed that two distension arthrographies with steroid combined with a home exercise program reduce shoulder disability and impairments. Adding a third distension arthrography does not seem to provide any further benefit.

Bilateral thumb's active range of motion and strength in de Quervain's disease: comparison with a normal sample

The aims of the present study were to characterize the thumb active range of motion (AROM) and strength impairments resulting from unilateral de Quervain's disease; to verify the adequacy of standard clinical assessment tools to quantify impairments resulting from this pathology; and to validate the utilization of the asymptomatic thumb as a reference to quantify the symptomatic thumb's deficits by comparing the performances of asymptomatic to control thumbs. The thumb's AROM and strength were evaluated bilaterally in 31 participants with unilateral de Quervain's disease and 18 control participants using clinical assessments involving the flexors and adductors of the thumb and experimental assessment devices measuring strength and mobility in several directions of the thumb's movements. A comparison was made between the results obtained from the symptomatic, asymptomatic, and control thumbs. The AROM performance of symptomatic thumbs was found to be reduced when compared to the asymptomatic and control thumbs for maximal thumb flexion (p=0.008 and 0.003, respectively) and total circumduction displacement (p<0.001). The strength performance of the symptomatic thumb was also found to be reduced when compared to the asymptomatic and control thumbs for palmar pinch strength (p<0.001 and 0.002, respectively) and for maximal voluntary effort in all directions (p<0.001). Differences in performance were also found between the asymptomatic and control thumbs, reaching the significance level for some movement parameters of the thumb circumduction evaluations and when palmar pinch strength results are normalized (p<0.001 and 0.009, respectively). This study revealed bilateral impairments of thumb AROM and strength for participants with de Quervain's disease, the impairments being more pronounced on the symptomatic side. This finding may question the validity of using the asymptomatic thumb as a standard measure to identify the symptomatic thumb's impairments associated with de Quervain's disease. The study also demonstrated the validity of using clinical evaluations when assessing impairments associated with this disease.

Active movement measurements of the shoulder girdle in healthy subjects with goniometer and tape measure techniques: A study on reliability and validity

In response to the current need to develop objective measurement techniques for active movements of the shoulder girdle, this study had two goals: 1) to evaluate the reliability of the active range of motion (AROM) of shoulder girdle in elevation, protraction, and retraction with use of a goniometer and a tape measure and 2) to present the criterion-related validity of the reliable movements. Thirty healthy subjects performed two trials of each shoulder girdle AROM. They were assessed by two physical therapists, who used both evaluation techniques on two occasions. The generalizability theory was used to compute intratester (test-retest) and intertester reliability using dependability coefficients (phi) and standard errors of measurement (SEMs). The shoulder girdle movements were then evaluated with a movement analysis system (Optotrak 3020). The Pearson product-moment correlation coefficient (r) and paired t-tests were used to compare the results of clinical measurements with those of the movement analysis system. Overall, the reliability with the tape measure was good (phi = 0.78-0.91; SEM's = 0.7-1.1 cm) for the elevation motion. The goniometer was only reliable for intratester measures (phi = 0.78-0.79; SEM = 2.7 degrees) for the elevation motion. Retraction was reliable with the tape measure alone (phi = 0.76-0.84; SEM's = 0.5-0.7 cm). The criterion-related validity analysis revealed that measuring shoulder girdle elevation with the tape measure and goniometer, and retraction with the tape measure were not valid when evaluated against a gold standard, thus, both techniques have limitations in assessing true elevation and retraction measurements.

Reliability of arthrometric measurement of shoulder lateral rotation movement in healthy subjects

Numerous pathologic conditions of the shoulder result in loss of range of motion with lateral rotation being one of the most affected movements. Therefore, it is essential to know the reliability of the methods to measure this motion from a treatment evaluation perspective. The purpose of this study was to examine the reliability of the shoulder lateral rotation movement measured by an arthrometric method. Fifteen healthy subjects participated in the study. The passive range of motion in lateral rotation of the shoulder was measured with an arthrometric method for three positions of shoulder abduction and with three loads. Two evaluators took each measurement on two separate occasions. The reliability was good at 60 degrees and 90 degrees abduction with dependability indexes (phi) ranging from 0.77 to 0.87 and SEMs lower than 5 degrees. The reliability at 25 degrees abduction was lower with dependability indexes (phi) ranging from 0.52 to 0.66 and SEMs of 7 degrees or 8 degrees. Reliability was highest with the heaviest load reaching 0.66, 0.84, and 0.87 for the 25 degrees, 60 degrees, 90 degrees abduction angles, respectively. In all conditions of measurement, differences between intratester and intertester reliability were minimal. Reliability of the shoulder lateral rotation measured by arthrometry was dependent on angle of abduction and load used to move the shoulder. Further studies are needed to confirm these findings in individuals with impaired shoulders.

Intertrial and test-retest reliabilities of Timed Bridge tests among frail older adults

The objective of this study was to assess the reliability of three versions of the Timed Bridge test (TB test) using the generalizability theory. A convenience sample of 30 frail older adults, from 65 to 94 years of age, performed three different TB Tests: 1) hold test (TB-Static); 2) five-repetitions dynamic test (TB-5rep); and 3) 60-second dynamic test (TB-60s). The tests were repeated twice on two occasions separated by a 48-hour interval. For each trial, the height of the bridge, the time of execution or the number of repetitions, the pain, and perceived effort were recorded. The intertrial and test-retest reliability for bridge heights were excellent. For the duration and the number of repetitions, a good intertrial reliability was found (0.83 <Phi< 0.94; SEMs 11.1 s, 2.9 s, and 4.2 rep), and the test-retest reliability was good for the TB-60 s and moderate for TB-Static and for the TB-5rep. The different tests were generally well tolerated by the subjects. The level of exertion perceived by the participants was light for the TB-5rep and moderate for the TB-Static and TB-60 s. The TB tests were simple to execute, showed good clinical applicability, and provided reliable measurements in a geriatric population.