Arthur A. Rodriquez

Gait training efficacy using a home-based practice model in chronic hemiplegia

OBJECTIVE The efficacy of a home practice model for gait training was evaluated in 18 hemiplegic subjects 2.3 years (range, 1 to 5) after stroke. DESIGN Uncontrolled case series. SETTING Referral center. SUBJECTS Patients at least 1 year poststroke referred to an outpatient rehabilitation program. INTERVENTION Patients were taught home programs in two or more 2- to 5-day blocks averaging 35 physical therapy (PT) contact hours (range, 9.5 to 62.5); training extended over a mean of 22 months (range, 10 to 65). Training emphasized weight bearing, balance, segmental control, stretching, and bracing. MAIN OUTCOME MEASURES Gait changes were measured using the newly developed Wisconsin Gait Scale (WGS). The patient-rated Falls Efficacy Scale (FES) was administered before and after training to 8 subjects, and the Health Status Questionnaire (HSQ) was retrospectively administered to all subjects to appraise subjective pretraining to posttraining changes and current psychological status. RESULTS The average WGS score significantly improved (p < .05). Patients perceived that gait training increased the quality of their functional activities (p < .05). In a subset of patients, the FES showed that fear of falling was decreased (p < .05). Perception of well-being was comparable to a normative nonstroke reference population except for physical functioning. Compared to the only other published series (using traditional outpatient programming), the current model was of comparable cost. CONCLUSION Despite the literature indicating a plateau in mobility function by 6 months after stroke, postacute training of gait in hemiplegic subjects using a home-based training model results in improved gait and the perception of improved function. Additionally, we provide validation for the newly developed Wisconsin Gait Scale, an instrument of gait measurement that may assist in comparing outcomes.

Strength, endurance, and work capacity after muscle strengthening exercise in postpolio subjects

OBJECTIVE To determine whether a 12-week home quadriceps muscle strengthening exercise program would increase muscle strength, isometric endurance, and tension time index (TTI) in postpolio syndrome subjects without adversely affecting the surviving motor units or the muscle. DESIGN A longitudinal study to investigate the effect of a 12-week exercise program on neuromuscular function and electromyographic variables. SETTING Neuromuscular laboratory of a university hospital. SUBJECTS Seven subjects were recruited from a cohort of 12 subjects who had participated in a previous exercise study. All subjects had greater than antigravity strength of the quadriceps. Upon completion of a postpolio questionnaire, all acknowledged common postpolio syndrome symptoms such as new fatigue, pain, and weakness; 6 of the 7 acknowledged new strength decline. INTERVENTION On Mondays and Thursdays subjects performed three sets of four maximal isometric contractions of the quadriceps held for 5 seconds each. On Tuesdays and Fridays subjects performed three sets of 12 dynamic knee extension exercises with ankle weights. MAIN OUTCOME MEASURES Neuromuscular variables of the quadriceps muscles were measured at the beginning and completion of the exercise program and included: isokinetic peak torque (ISOKPT, at 60 degrees/sec angular velocity) and total work performed of four contractions (ISOKTW), isometric peak torque (MVC), endurance (EDUR, time subject could hold isometric contraction at 40% of the initial MVC), isometric tension time index (TTI, product of endurance time and torque at 40% of MVC), and initial and final ankle weight (WGT, kg) lifted. Electromyographic variables included: fiber density (FD), jitter (MCD), and blocking (BLK) from single fiber assessment and median macro amplitude (MACRO). Serum creatine kinase (CK) was also measured initially and at 4-week intervals throughout the study. RESULTS The following variables significantly (p < .05) increased: WGT by 47%, ISOKPT, 15%, ISOKTW, 15%; MVC, 36%; EDUR, 21%; TTI, 18%. The following variables did not significantly (p > .05) change: FD, MCD, BLK, MACRO, and CK. CONCLUSIONS This home exercise program significantly increased strength, endurance, and TTI without apparently adversely affecting the motor units or the muscle, as the EMG and CK variables did not change.

Late effects of polio: Critical review of the literature on neuromuscular function

Many individuals who have had poliomyelitis are now complaining of several new problems attributed to their former illness including muscle atrophy; fatigue; progressive weakness; and muscle, back, and joint pain. This paper critically examines the literature regarding the neuromuscular effects of poliomyelitis. Weakness resulting from poliomyelitis was due to destruction of anterior horn cells. After the illness, muscle strength was partially recovered as a result of several physiologic adaptive mechanisms including terminal sprouting and reinnervation, myofiber hypertrophy, and, possibly, myofiber type transformation. Several pathophysiologic and functional etiologies have been proposed for late neuromuscular deterioration, but none has been proven. In fact, to date, there is no objective evidence documenting progressive loss of strength in polio survivors. Studies attempting to differentiate polio survivors with and without symptoms of deterioration have resulted in conflicting results; however, it appears reasonable to conclude that symptomatic postpolio subjects had a more severe illness with greater loss of neuromuscular function. Exercise may be helpful for many postpolio patients, but the prescription must be tailored to the individual to avoid problems of overuse or excessive fatigue.

Needle electromyographic evaluation of patients with myofascial or fibromyalgic pain

Several past studies have evaluated the electromyographic activity of myofascial trigger points with conflicting results. This study was performed to determine whether spontaneous activity or motor unit activity was present in patients with focal myofascial pain or fibromyalgia. Using routine needle electromyographic techniques, we sampled reproducibly tender focal areas (tender points), similar tender areas with pain referral (trigger points), associated muscle bands and adjacent uninvolved musculature. Twenty-five subjects (14 females, 11 males, mean ± SD age 43 ± 14 years) were studied; twenty-one subjects with focal myofascial pain and four with fibromyalgia. Spontaneous fibrillatory or positive sharp wave potentials were not found in any muscle in the 25 subjects. There was no evidence of focal motor unit activity in the tender points, trigger points or associated muscle bands in either group. Motor unit recruitment was similar in all areas sampled. We conclude that no electrodiagnostic evidence of ongoing denervation or focal muscle spasm is found in association with focal myofascial pain or fibromyalgia.

Choline and betaine aldehyde oxidation by rat liver mitochondria

Abstract 1. The question of the ability or inability of rat liver mitochondria to oxidize externally added or internally generated betaine aldehyde has been reexamined. Well washed mitochondria were demonstrated to contain approx. 7% of the post-nuclear betaine aldehyde dehydrogenase as an integral component. The enzyme is approximately equally distributed between the inner membrane and the intermembrane plus matrix fractions. Significantly, none was found in the outer membrane fraction. The mitochondrial enzyme was shown to be functional under all the conditions tested; betaine aldehyde generated within the mitochondria by choline oxidation or added externally was oxidized to betaine in significant amounts. 2. The stoichiometry for the complete oxidation of choline or externally added betaine aldehyde was confirmed to be 2 and 1 moles, respectively, of O 2 utilized per mole of substrate added. Depending on the reaction conditions employed, considerable variation in the relative amount of choline oxidase and betaine aldehyde oxidase activities of mitochondria was observed when they were allowed to oxidize only a portion of the choline added. The necessity of measuring the contribution of betaine aldehyde oxidase in studies of choline oxidase is discussed. 3. Reasons for the discrepancies in the literature concerning the ability of mitochondria to oxidize betaine aldehyde are discussed.

Botulinum toxin injection of spastic finger flexors in hemiplegic patients.

OBJECTIVE To assess the outcomes of botulinum toxin injection of spastic finger flexors followed by intensive training of finger extensors. DESIGN Fourteen subjects with chronic hemiplegia spasticity of the upper limb had electromyographic-guided botulinum toxin injection into the long finger flexors. All patients presented with minimal active finger extension with the wrist flexed, sustained clonus of the finger flexors, functional proximal arm function, and absence of fixed contracture. Cadaver dissections directed selection of two injection sites: the flexor digitorum sublimis and the flexor digitorum profundus. Fifty mouse units of botulinum toxin were injected into each muscle. After injection, the subjects were instructed in a home program of stretching the long finger flexors, upper limb weight bearing with a weight-bearing splint, and exercise to improve finger extension control. RESULTS Compared with preinjection measures, assessment the first week after the initial injection showed significantly reduced tone, reduced clonus, and greater active finger extension with the wrist in the neutral position. Four months later, the Ashworth scale increased to preinjection levels in the six subjects with repeated injections but was again decreased postinjection. Active finger extension with the wrist in the neutral position and clonus showed a statistically nonsignificant trend toward cumulative improvement after the second injection. CONCLUSION The greatest change in finger extension and spasticity reduction occurred after the first injection. Continued significant improvement in finger extension was not observed.

Psychologic characteristics of polio survivors: A preliminary report

Ninety-three men and women with histories of polio were administered the Symptom Check List-90 Revised (SCL-90R), Psychosocial Adjustment to Illness Scale-Self Report (PAIS-SR), and a questionnaire about their polio histories. The SCL-90R and PAIS-SR are measures of emotional and psychosocial functioning. Two samples were used: a clinic sample (n = 71) and a postpolio support group sample (n = 22). Initial results for both on the SCL-90R and PAIS-SR indicated elevated scores on a number of subscales. SCL-90R subscale elevated scores for men included those for somatization, depression, anxiety, hostility, and phobia, whereas for women there were elevations on measures of somatization, depression, anxiety, and psychoticism. Elevations were found in the following subscales on the PAIS-SR (pooling men and women): health care orientation, social environment, and extended family relationships. Men scored slightly, but not significantly, higher than women in the SCL-90R except for the hostility subscale, in which the difference was significant (p less than 0.05). Symptom profiles indicated psychologic distress. Comparisons with variables associated with polio and its late effects (such as severity of initial polio, use of an iron lung during initial illness, number of involved limbs, etc) were not statistically significant.

Low-intensity, alternate-day exercise improves muscle performance without apparent adverse effect in postpolio patients

The purpose of this study was to examine the effect of a low-intensity, alternate-day, 12 wk quadriceps muscle-strengthening exercise program on muscle strength and muscle and motor unit integrity in 12 postpolio patients. Patients performed six to ten repetitions of a 5-s duration knee extension exercise with ankle weights. After completing six repetitions, patients rated the perceived exertion (RPE) in the exercised muscle. The patient continued repetitions until RPE was >/= 17 or ten repetitions were performed. The weight was increased the next exercise day whenever the RPE was < 17 after ten repetitions. Before and after the training program, median macroamplitude as well as jitter and blocking were determined electromyographically (EMG), serum creatine kinase (CK) was measured, and quadriceps muscle strength was assessed. The ankle weight lifted after 2 wk of training and at the end of the program were also recorded. Although the ankle weight lifted at the end of the program significantly (P < 0.05) increased from a mean +/- SD of 7.1 +/- 2.7 to 11.2 +/- 4.7 kg, the dynametrically determined muscle strength measures did not significantly (P > 0.05) increase. The EMG and the serum CK variables also did not significantly (P >0.05) change as a result of the exercise program. We conclude that performance was improved, as demonstrated by an increase in the amount of weight the patients lifted in the exercise program. No evidence was found to show that this program adversely affected the motor units or the muscle as the EMG and CK did not change.

Functional psychomotor deficits associated with carpal tunnel syndrome

A reliable task was developed for investigating functional deficits associated with carpal tunnel syndrome (CTS). A rapid pinch and release psychomotor task utilizing muscles of the hand innervated by the median nerve was administered using a strain gauge dynamometer and providing limited force feedback. The motor performance characteristics studied were speed and force control. An experiment was conducted for studying the effects of force level, hand dominance, test-retest reliability, learning, and inter-subject variability using 13 subjects free from any hand disabilities or symptoms. A companion study was also conducted using 17 normal subjects and ten subjects diagnosed having CTS to investigate differences between CTS and control subjects. Dominant hands performed 4% to 8% better than the non-dominant hands by having a greater pinch rate, a smaller overshoot force, and less time above the upper force level and below the lower force level. Control subjects performed 25% to 82% better than CTS subjects. Age contributed 6% of the total variance for pinch rate and 7% of the total variance for the time below the lower force level. The results suggest that people suffering from CTS may experience similar functional psychomotor deficits in daily living and manual work activities.

Efficacy of Repeated Botulinum Toxin Injections as a Function of Timing

This pilot study was designed to determine if the interval between repeated botulinum toxin injections influenced physiologic and histologic effects on laryngeal muscles in a rat model. The physiologic measurements included digitized videomicroscopic recording of vocal fold movement and electromyography. The histologic measurements included muscle fiber size and digitized optical density of laryngeal muscles after glycogen depletion by electrical stimulation. The results demonstrated that the effect of timing of the second injection was strongly correlated to laryngeal changes. Most notable were results in the subjects that underwent injections 6 weeks apart. We hypothesize that these findings might be related to terminal axonal sprouting with reinnervation. The results from this study help confirm and expand the validity of using the rat laryngeal model to understand the effect of botulinum toxin. Moreover, we believe that the data might be extrapolated to prove useful in predicting human responses to botulinum toxin treatment for functional dystonias such as spasmodic dysphonia.