Activation of selected trunk muscles during symmetric functional activities in poststroke hemiparetic and hemiplegic patients.

OBJECTIVE: To compare the EMG activity between the recti abdominii muscles and between the lumbar erector spinae muscles in hemiparetic and hemiplegic patients during functional symmetric trunk movements and to compare patients' EMG activity profiles with those of healthy controls. METHODS: EMG activity from the selected muscles was recorded during three symmetric and time controlled trunk exercises. Data analysis was based on values of cross correlations and of ratios between EMG activity of the bilateral corresponding muscles. RESULTS: In all groups, the highest cross correlations were obtained for both muscles when the muscles acted as prime movers. For the recti abdominii muscles, these values in the patients were comparable with those of the healthy subjects, whereas for the extensor muscles, the highest synchronous activity was displayed in healthy subjects and the lowest in hemiplegic patients. Laterality differences in the amount of EMG activity of the recti abdominii muscles were not biased towards one side. For the extensor muscles, in the controls, the activation levels were higher in the left erector spinae muscle than in the right one in two of the three exercises. Similarly, in the extensor muscles of the hemiparetic patients, activity on the paretic side was higher than on the non-paretic side in two exercises. CONCLUSIONS: In patients with a supratentorial poststroke hemiparesis or hemiplegia, bilateral corresponding axial trunk muscles co-contract during symmetric trunk activities. Synchronous activation is at its highest level during voluntary dynamic tasks and is greater in the recti abdominii than in the erector spinae muscles. For both muscles, EMG activation levels on the paretic side were not lower than on the non-paretic side. Thus, the assertion that the muscles on the paretic side are activated to a lesser extent than their counterparts on the non-paretic side during symmetric trunk movements was not confirmed.

Total knee arthroplasty in the elderly: patients' self-appraisal 6 and 12 months postoperatively.

The objective of this work was to study patients' self-appraisal of total knee arthroplasty (TKA) 6 and 12 months postoperatively, and to establish which factors determine dissatisfaction from surgery. The study group consisted of 79 patients subjected to TKA who underwent rehabilitation in a specialized institution from which they were discharged home after becoming independently ambulatory and capable of independent home care. Data were collected by interviews and physical examinations which were conducted upon admission to the rehabilitation program and at the patients' homes 6 and 12 months postoperatively. Descriptive statistics and logistic regression were applied for data analysis. Results of the 1-year follow-up indicated a decrease in the prevalence of pain in the postoperated knee and improvement in ambulatory capacities. The frequency of reliance on a walking aid and the prevalence of pain in the nonoperated knee were not substantially changed, however. In 27% of the subjects pain in the nonoperated knee had worsened at 1 year. One third of the respondents expressed dissatisfaction from the operation. Outcomes of the logistic regression analysis pointed to pain in both the ipsi- and contralateral knee and to the limitations in using stairs as the variables which significantly affected the levels of dissatisfaction 1 year postoperatively. Dissatisfaction could have resulted from inappropriate expectations from either misinterpretations or limited prior knowledge of the likely results of the operation.

Repetitive practice of a single joint movement for enhancing elbow function in hemiparetic patients.

The primary goal of this study was to assess whether repetitive practice of flexion-extension movements of the affected elbow in hemiparetic patients enhances performance and to compare the effects of this practice mode to the effects of the physical therapy variable exercise program which is routinely applied during sessions. Subjects were 27 poststroke hemiparetic patients, residents of a rehabilitation institute, divided into an experimental (n = 15) and a control group (n = 12). The former were treated with 800 repeated elbow movements in a maximal predetermined amplitude of 80 degrees, provided in 8 equal sessions every other day. The latter received 10 min. of conventional physical therapy for the paretic upper extremity at similar time intervals. Pre- and posttreatment assessments included the bilateral measurements of kinematic variables and activation latencies of the biceps and triceps brachi muscles as well as motor and functional tests. For all criterion variables, the findings pointed to comparable improvement in both groups. It was concluded that repetitive elbow movements had no unique training effect on the kinematics of movement and on activation latencies of the primary muscles controlling elbow function in hemiparetic patients. Further, transfer of the effects of training to execution of movements towards and from the mouth was also comparable in both groups, pointing again to there being no particular advantage in using repetitive movements as a training mode for enhancement of elbow function in hemiparetic patients.

Somatosensory evoked potentials of the posterior tibial nerve in hemiparetic patients: relation to stance balance and walking ability.

OBJECTIVES: To examine the association between stance ability and walking performance of poststroke hemiplegic patients and their posterior tibial nerve somatosensory evoked potentials (SEPs). DESIGN AND SETTING: Fifteen patients, residents of a geriatric rehabilitation hospital, were evaluated twice, with a 2-week interval between sessions. In each session, clinical tests of stance balance and walking ability were performed, and bilateral SEPs to stimulation of the posterior tibial nerve were recorded. Eight healthy, age-matched control subjects underwent the same tests in a single session, but SEPs were recorded unilaterally. Correlation analysis and analysis of variance (ANOVA) were used for studying the prognostic value of the initial posterior tibial nerve SEP measurements as well as the within- and between-sessions relationships between the clinical-functional tests and the SEP data. RESULTS: No significant correlations between the initial SEP values and functional improvement were established. Within each session, positive significant correlations existed between decreased latencies of several of the medium-latency SEP waves and the performance of stance and gait tasks. However, the between-sessions improvement in stance balance was not correlated with a decrease in latency of the SEP peaks or with an increase in their amplitudes. As to walking ability, in those patients whose gait significantly improved, a significant shortening of P37 and P54 latencies took place. CONCLUSIONS: The association between the initial and/or the 2-week changes in SEP of the posterior tibial nerve and improvement in stance and walking abilities is equivocal. In addition, the applicability of SEP measurements is limited by patients' physical status and cooperation. The clinical significance of posterior tibial nerve SEP testing in poststroke hemiparetic patients is therefore debatable.

Electromyographic and positional changes in the elbows of spastic hemiparetic patients during walking.

The displacement of the paretic elbow of hemiparetic patients into flexion during walking is an acknowledged associated reaction characteristic of upper limb spasticity. The main purpose of this study was to examine the step-dependent pattern and magnitude of the angular and electromyographic changes which take place during this flexion movement. Steps-related changes in elbow angle were measured on the paretic side of 14 hemiparetic patients during walking with a 4-point cane. The EMG activity of the ipsilateral biceps and triceps brachii muscles was concomitantly recorded. The activity of the brachioradialis muscle in 8 patients was monitored as well. In another trial, the angular and electromyographic activities were measured bilaterally in 7 patients during free walking. Flexion movement on the paretic side was characterized by a steep increase in flexion occurring during the first 4 steps, followed by a more gradual rise with successive stepping. Neither the electromyographic activity of the elbow flexor nor that of the extensor muscles was related to that flexion movement. The excursion into flexion on the non-paretic side was smaller than on the paretic side and incorporated flexion-extension fluctuations. The associated reaction at the paretic elbow during walking is a postural response which is triggered by the balance perturbation in the gait activity. It starts with a steep rise in flexion which seems to be reflexive in nature. The preservation of elbow flexion during walking may be an expression of stiffening of the elbow flexor muscles fibers.