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At least 91 records · Page 5Linked to original sources
PubMed2001

Proprioception in anterior cruciate ligament reconstruction. Endoscopic versus open two-tunnel technique. A prospective study.

ACL-reconstruction with patellar tendon autograft is a standard procedure which can be performed arthroscopically with a femoral half tunnel drilled from the joint or using the two-tunnel technique with medial miniarthrotomy and additional femoral approach. The arthroscopic procedure with single incision was hypothesized to improve proprioception and to provide earlier rehabilitation. Twenty-nine patients with chronic ACL-deficiency were included in the prospective study. Fifteen patients were operated endoscopically, 14 patients using the two-tunnel technique. Proprioception, Lysholm and Tegner scores as well as stability (KT-1000) were assessed preoperatively, 3 and 6 months postoperatively as well as after 3.9 +/- 0.4 years. A significant deficit of proprioception was assessed in both groups preoperatively. Six months postoperatively, both groups showed a restitution of proprioception near full extension and full flexion of the knee. In the mid-range position, the proprioception could not be restored. At the final examination after 3.9 years, the deficit documented in the mid-range position still persisted. There were no differences in proprioception, clinical results and stability between the arthroscopic and the open technique.

Adult↗
PubMed2003

Influence of neck proprioception on vibration-induced postural sway.

OBJECTIVE: Several reports have shown that the direction of the postural responses induced by vestibular stimulation is affected by the positions of the neck and torso. The aim of this study was to investigate whether the postural responses to vibratory proprioceptive stimulation of the calf muscles are affected by the position of the head and thus by proprioceptive and vestibular information from the neck and head. MATERIAL AND METHODS: Ten normal subjects were exposed to vibratory proprioceptive stimulation of the calf muscles when the head was maintained in five different positions: in a neutral position facing forwards, with the head turned to the right or left sides or with the head tilted backwards or forwards. Body movements were evaluated by analyzing the anteroposterior and lateral torques induced towards the supporting surface. RESULTS: The analysis showed that only the anteroposterior body sway was significantly affected by the position of the head. The anteroposterior postural responses were primarily increased during the tests with the head tilted backwards or forwards, whereas the postural responses were unaffected by head torsion towards the sides. The lateral responses were primarily affected by vision and not by the position of the head. CONCLUSIONS: The findings suggest that the responses evoked by vibratory proprioceptive stimulation of the calf muscles may be affected by different mechanisms, either by purely proprioceptive information or by an interaction between proprioceptive and vestibular information. Moreover, the increasing difference between the test conditions over time suggests that fatigue of the neck muscles may be one of the factors affecting the responses induced by the perturbations.

Adult↗
PubMedDate not supplied

Proprioceptive and sensorimotor performance in Parkinson's disease.

We explored the effects of random whole-body vibration on leg proprioception in Parkinson's disease (PD). In earlier studies it was found that this treatment leads to improved postural control in these patients. Thus, one could speculate that these effects result from modified proprioceptive capabilities. Twenty-eight PD patients were subdivided in one experimental and one control group. Proprioceptive performance was analyzed using a tracking task basing on knee extension and flexion movements. Treatment consisted of 5 series of random whole-body vibration taking 60 seconds each. Control subjects had a rest period instead. Prominent over- and undershooting errors were found in both groups representing proprioceptive impairments. No significant differences became evident, however, either between pre- and post-tests or between experimental and control group. One might therefore conclude that spontaneous improvements in postural control are not directly connected with proprioceptive changes. Nevertheless, one also should keep in mind the general aspects and difficulties of analyzing proprioception.

Humans↗
PubMed2002

Proprioception in poor- and well-functioning anterior cruciate ligament deficient patients.

The aim of this study was to examine proprioception with and without muscle tension and knee function in two groups of chronic (> 1 year post-injury) patients with deficient anterior cruciate ligaments with distinctly different functioning levels. The well (WF) and poor functioning (PF) group was defined as those with a Tegner/Lysholm score equal to or greater than 6/95 (WF, n = 7), and equal to or less than 4/83 (PF, n = 7), respectively. Clinical examination included a Lachman, and a Pivot shift test, as well as a KT2000 arthrometer assessment. Single and triple hop tests assessed one-legged performance. Proprioception was measured as threshold of passive movement detection, and as the ability to reproduce flexion angles with (20% and 50% MVC) and without muscle tension. Mean Tegner/Lysholm scores were: WF: 7 (range 6-8)/98 (range 95-100), PF: 2 (range 1-4)/71 (range 62-80). There were significant differences between the Pivot shift tests of the groups (p = 0.01). The laxity (KT2000) assessment yielded a significant (3 mm, p < 0.05) side-to-side difference in both groups. One-leg hop tests yielded no side-to-side differences in any of the groups or between the groups. There were no significant differences between the groups in any of the proprioceptive tests, except in one of the angle reproduction tests with muscle tension (20%, p < 0.05). WF had larger mean errors than PF. There was not found any side-to-side difference in any of the proprioceptive tests, except in one of the angle reproduction tests with muscle tension (WF, 20%, p < 0.05). In conclusion, these data suggest that subjects with long standing anterior cruciate ligament deficiency in the present study did not have a knee joint proprioceptive deficit as measured by some commonly accepted methods. There was no difference in proprioception between the two groups despite their markedly different function levels and pivot shift evaluated knee laxity.

Activities of Daily Living↗
PubMedDate not supplied

Effect of age and activity on knee joint proprioception.

Falls lead to significant morbidity and mortality in persons older than 65 years of age. Impaired proprioception may be a contributing factor to falls, and this may be influenced by the level of habitual physical activity. The primary purpose of this study was to investigate knee joint proprioception among young volunteers and active and sedentary elderly volunteers. Knee joint proprioception was measured through reproduction of static knee angles using a Penny and Giles electrogoniometer. The secondary purpose of this investigation was to test the reproducibility of the Penny and Giles electrogoniometer in measuring static knee angles. Sixteen young subjects (age range, 19-27 years) and 24 elderly subjects (age range, 60-86 years) participated. Subjects were given a screening history and physical examination to exclude neuromuscular or vestibular disorders or lower limb injuries. Knee joint proprioception was measured two times during one week. The elderly group was separated into active and sedentary subgroups based on their level of activity during the past year. The electrogoniometer was placed laterally across the dominant knee joint. From the prone position each subject attained one of ten randomly predetermined knee joint angles from 10 degrees to 60 degrees. The subject then returned to the starting position and reproduced the test angle. The absolute angular error (the absolute difference between the test angle and subject perceived angle of knee flexion) was determined. A positive correlation was found between control visits for all subjects (r = 0.88), and significant differences were observed between young (mean, 2.01 +/- 0.46 degrees) and active-fold (mean, 3.12 +/- 1.12 degrees; P < 0.001), young and sedentary-old (mean, 4.58 +/- 1.93 degrees; P < 0.001), and active-old and sedentary-old (P < 0.03). These findings demonstrate that the Penny and Giles electrogoniometer is a reproducible device for measuring knee joint angles in both young and elderly subjects. Furthermore, we found that proprioception is diminished with age and that regular activity may attenuate this decline. One strategy to reduce the incidence of poor proprioception and fall with ageing may be regular exercise.

Accidental Falls↗
PubMed2001

Knee bracing after ACL reconstruction: effects on postural control and proprioception.

PURPOSE: To evaluate the effects an anterior cruciate ligament (ACL) brace has on various measures of knee proprioception and postural control. METHODS: Thirty subjects (mean age 27 +/- 11 yr) having undergone unilateral ACL reconstruction were tested with and without wearing their own custom-fit brace on their involved limb. Proprioception was assessed using joint angle replication tests completed on an isokinetic dynamometer. Postural control was assessed using a series of single-limb standing balance tests completed on a force platform. The balance tests included: 1) standing on the stable platform with eyes open, 2) standing on a foam mat placed over the platform with eyes open, 3) standing on the platform with eyes closed, and 4) standing on the platform after landing from a maximal single-limb forward hop. RESULTS: The brace provided a small but statistically significant improvement in proprioception (mean reduction in error scores between target and reproduced angles = 0.64 +/- 1.4 degrees, P = 0.02). For the postural control tests, there was a significant brace condition by test situation interaction (P = 0.02), with the brace providing a small but statistically significant improvement during the test completed on the stable platform with eyes open (mean reduction in center of pressure path length = 4.2 +/- 8.4 cm, P = 0.02) but not during the other more challenging test situations. Additional post hoc analyses indicated that the relationship between knee proprioception and postural control measures were low and not significant (r = 0.003 to 0.19, P > 0.32), consistent with the suggestion that changes in knee proprioception can occur in the absence of substantial changes in postural control. Also, standing balance tests that challenged the somatosensory contribution to postural control (i.e., those completed on foam, or with eyes closed) were significantly related to single-limb forward hop distances (r = -0.4, P < 0.05), whereas performance during the proprioception test was not (r = 0.1, P > 0.50). CONCLUSIONS: In general, bracing appears to improve performance during tasks characterized by relatively limited somatosensory input but not during tasks characterized by increased somatosenory input. The small magnitude of the improvements, coupled with their apparent lack of carry over to more difficult and functionally relevant tasks, questions the clinical benefit of the present effects of bracing.

Adult↗
PubMed1998

The measurement of lumbar proprioception in individuals with and without low back pain.

STUDY DESIGN: A clinical trial comparing a back pain group with a pain-free group. OBJECTIVES: To investigate whether proprioceptive deficits existed in a group of individuals reporting low back pain. SUMMARY OF BACKGROUND DATA: Little work has so far been conducted on the measurement of proprioception in the spine. Those studies that have been carried out, however, have failed to identify proprioceptive deficits in individuals with back pain. Previous work on peripheral joints has revealed that proprioception is affected with muscular or joint injury or degeneration. METHODS: Forty individuals took part in the study, 20 with back pain and 20 with no pain. Participants were required to reproduce a predetermined target position, in standing and four-point kneeling, 10 times in 30 seconds. A computer screen was used to provide visual feedback on position. A mean deviation from the target position was obtained for each individual. A measurement of left elbow position sense was conducted in five individuals from each group to establish differences in short-term motor memory between the groups. RESULTS: There were no differences between the subject groups in terms of short-term motor memory (P > 0.05). A two-way analysis of variance between subject groups and position to identify differences in accuracy (deviation from the target) found that there were differences between subject groups in either position (P < 0.05). There was no significant difference in accuracy between the positions used (P > 0.05). CONCLUSIONS: Differences in proprioception do exist between individuals with back pain and those free from back pain. Further research needs to be undertaken on proprioceptive exercise programs and their effect on back pain.

Adult↗
PubMed1998

The effects of muscular fatigue on shoulder proprioception.

OBJECTIVE: To assess the influence of muscular fatigue on active and passive shoulder proprioception within the midrange of rotation. DESIGN: A randomized controlled, before-and-after design. SETTING: Neuromuscular research laboratory. PARTICIPANTS: Twenty recreationally active men (mean age, 23.81+/-2.77 years) were randomly assigned to either a control or a fatigue group. Exclusion criteria were any history of upper extremity injury or pathology, cardiovascular disease, or disease affecting the sensory system. INTERVENTION: Shoulder proprioception was assessed by active reproduction of passive positioning (ARPP), active reproduction of active positioning (ARAP), reproduction of passive positioning (RPP), and threshold to detect passive motion (TTDPM). For each test direction, the experimental group performed two bouts of maximal reciprocal concentric isokinetic internal and external contractions at 180 degrees/s until peak torque decreased to 50% of the established maximum voluntary contraction. After two bouts of the fatigue protocol, subjects were randomly assessed for proprioception into internal or external rotation. MAIN OUTCOME MEASURES: The absolute angular error for active and passive proprioception was measured on the Biodex System II Isokinetic Dynamometer (Biodex Medical Inc., Shirley, NY, U.S.A.) and a proprioception testing device, respectively. MAIN RESULTS: A two-factor repeated measures analysis of variance revealed no significant interactions between the experimental and control groups for ARPP, ARAP, RPP, or TTDPM. CONCLUSIONS: Shoulder proprioception was not affected by the short-duration, high-intensity protocol used in this study. This may be due to the lack of an extended recovery period observed with this type of fatigue regimen.

Adult↗
PubMed1994

Proprioceptive, visual and vestibular thresholds for the perception of sway during standing in humans.

1. Thresholds for the perception of postural sway induced by gentle perturbations were determined for five normal standing subjects. In this context we understand 'perception' to mean 'able to give a subjective report'. The thresholds for the perception of movements that were equivalent to sway in velocity and amplitude were determined when the available sensory input was limited to only one, or a pair, of the vestibular, visual, and proprioceptive systems. To examine vestibular inputs alone, vision was excluded and the whole body was moved with the ankles in a fixed position. To examine visual inputs alone, the body was kept stationary and a 'room' was moved around the subjects to simulate the relative visual-field movement that occurs during standing. To limit the available sensory input to proprioception from the legs, subjects were held stationary and balanced a load that was equivalent to their own body using their ankles. In this situation, perturbations were applied to the 'equivalent body' and these could only be perceived from the resulting ankle movements. Thresholds for perceiving ankle movements were also determined in the same posture, but with the leg muscles bearing no load. 2. The thresholds for the perception of sway during standing were very small, typically 0.003 rad at a velocity of 0.001 rad s-1, and even smaller movements were perceived as the mean velocity of the sway increased up to 0.003 rad s-1. No difference was found between the thresholds for perceiving forward sway and backward sway. Eye closure during standing did not affect the threshold for perceiving sway. 3. When sensory input was limited to proprioception from the legs, the thresholds for the perception of passive ankle movements were equivalent to the thresholds for the perception of sway during standing with all sensory inputs available. When the leg muscles were relaxed, the thresholds for perceiving ankle movements increased approximately twofold. 4. The visual thresholds for perceiving movement were higher than the proprioceptive thresholds at slower velocities of movement, but there was no difference at higher velocities. 5. Both the proprioceptive and visual thresholds were sufficiently small to allow perception of the sway that was recorded when the subjects stood normally in a relaxed manner. In contrast, the vestibular thresholds were an order of magnitude greater than the visual or proprioceptive thresholds and above the largest sway movements that were recorded during normal standing.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1995

Proprioceptive coordination of discrete movement sequences: mechanism and generality.

A "discrete" movement sequence is defined as a movement with a single goal that involves a series of overlapping joint rotations. Reaching-and-grasping and throwing are examples of discrete movement sequences. The central nervous system (CNS) can use reafferent proprioceptive information from one joint rotation in a sequence to coordinate subsequent rotations at other joints. The experiments reported in this paper demonstrate how the human CNS uses proprioceptive information to coordinate discrete movement sequences. We examined the mechanism (at an information processing level) underlying proprioceptive coordination and the generality (i.e., the boundary conditions) of these mechanisms as they apply to everyday movement sequences. Adult human subjects performed a discrete movement sequence that resembles backhand throwing: elbow extension followed by hand opening. The task was to open the hand as the elbow passed through a prescribed "target" angle. We eliminated visual information and made the arrival time at the target angle unpredictable so that the available kinematic information was provided exclusively by proprioception. The subjects were capable of performing this motor task with a high degree of precision, thereby demonstrating that the nervous system can use proprioceptive input to coordinate discrete movement sequences. Our data indicate that precise coordination is achieved by extracting kinematic information related to both the velocity of elbow rotation as well as the elbow position during movement (i.e., "dynamic position"). Dynamic position information appears to be encoded as both absolute joint angle and angular distance, although more precisely as angular distance. Although our experiments were conducted under rather restrictive laboratory conditions, this mechanism of motor coordination might also apply to everyday movement. Our results suggest that this mechanism could be employed for passive as well as active movement sequences, with and without opposing loads; it could exert its influence in discrete movement sequences as brief as 210 ms or as long as 1.5 s; and it does not involve any significant degree of learning (this proprioceptive mechanism appears to be readily available for use on the first attempt of a novel motor task).

Adult↗
PubMed2005

Interaction of visual and proprioceptive feedback during adaptation of human reaching movements.

People tend to make straight and smooth hand movements when reaching for an object. These trajectory features are resistant to perturbation, and both proprioceptive as well as visual feedback may guide the adaptive updating of motor commands enforcing this regularity. How is information from the two senses combined to generate a coherent internal representation of how the arm moves? Here we show that eliminating visual feedback of hand-path deviations from the straight-line reach (constraining visual feedback of motion within a virtual, "visual channel") prevents compensation of initial direction errors induced by perturbations. Because adaptive reduction in direction errors occurred with proprioception alone, proprioceptive and visual information are not combined in this reaching task using a fixed, linear weighting scheme as reported for static tasks not requiring arm motion. A computer model can explain these findings, assuming that proprioceptive estimates of initial limb posture are used to select motor commands for a desired reach and visual feedback of hand-path errors brings proprioceptive estimates into registration with a visuocentric representation of limb position relative to its target. Simulations demonstrate that initial configuration estimation errors lead to movement direction errors as observed experimentally. Registration improves movement accuracy when veridical visual feedback is provided but is not invoked when hand-path errors are eliminated. However, the visual channel did not exclude adjustment of terminal movement features maximizing hand-path smoothness. Thus visual and proprioceptive feedback may be combined in fundamentally different ways during trajectory control and final position regulation of reaching movements.

Adaptation, Physiological↗
PubMed1994

Extraocular muscle proprioception functions in the control of ocular alignment and eye movement conjugacy.

1. The function of extraocular muscle proprioception in the control of eye movements is uncertain. We tested the hypothesis that proprioception contributes to the long-term regulation of ocular alignment and eye movement conjugacy. 2. Eye movements were recorded in monkeys with unilateral extraocular muscle palsies, before and after proprioceptive deafferentation of the paretic eye. Following deafferentation, ocular alignment and saccade conjugacy gradually worsened over several weeks. In contrast, disconjugate adaptation induced by habitual binocular viewing with a prism (disparity-mediated adaptation) occurred normally after deafferentation. 3. These results provide the first evidence that proprioception functions in the control of eye movements in primates, and indicate that proprioception contributes to the long-term adaptive mechanisms that regulate ocular alignment during fixation and saccades. The error signal used in this process may be derived from a mismatch between the efference copy and proprioceptive afference.

Afferent Pathways↗
PubMed1996

The effects of muscle fatigue on and the relationship of arm dominance to shoulder proprioception.

It is hypothesized that proprioceptive information plays an important role in joint stabilization and that muscle fatigue may alter proprioceptive ability. The purpose of this study was to determine what effect shoulder muscle fatigue has on glenohumeral proprioception and to examine the relationship between arm dominance and shoulder proprioception. Eighty subjects without a history of glenohumeral pathology participated. Each was seated on an isokinetic dynamometer with a randomly selected shoulder positioned in 90 degrees of abduction and elbow flexion. With vision blinded, the arm was passively positioned in 75 degrees of external rotation for 10 seconds, then passively returned to the neutral starting position. Three trials each of active and passive repositioning (2 degrees/sec) were recorded. Following a fatigue protocol, both active and passive repositioning were reassessed. Testing order was randomized. A significant difference was detected between pre- and post-fatigue scores. No significant difference was detected between dominant and nondominant extremities. No relationship between arm dominance and shoulder proprioception was established. It is concluded that shoulder proprioception is diminished in the presence of shoulder muscle fatigue, suggesting clinical rehabilitation protocols must emphasize increasing muscular endurance.

Adult↗
PubMed1999

Proprioception in people with anterior cruciate ligament-deficient knees: comparison of symptomatic and asymptomatic patients.

STUDY DESIGN: Nonrandomized prospective study. OBJECTIVE: To evaluate proprioception in 2 groups of patients with anterior cruciate ligament (ACL) deficiency who had different severity of symptoms. BACKGROUND: Defective proprioception has previously been found in patients with ACL-deficient knees. It has been suggested that sensory receptors of the ACL and other knee joint ligaments contribute to proprioception and knee joint function and stability. METHODS AND MEASURES: A total of 17 patients with ACL deficiency (mean [SD] age, 28.8 +/- 5.6 years; range, 22-39 years) with few, if any, symptoms were compared with 20 patients with ACL deficiency (mean [SD] age, 26.6 +/- 6.1 years; range, 18-39 years) having instability and episodes of giving way. The groups were compared with each other and with an age-matched reference group of 19 nonimpaired subjects. Their mean (SD) age was 25.6 +/- 3.7 years (range, 20-37 years). Three tests of proprioception were used: threshold to detection of passive motion from 2 starting positions (20 degrees and 40 degrees of knee flexion) toward flexion and extension, active reproduction of a 30 degrees passive angle change, and visual reproduction of a 30 degrees passive angle change. The Wilcoxon rank sum test was used for between-group comparisons. RESULTS: Symptomatic patients had higher threshold to detection of passive motion in their injured side in the flexion trial from 20 degrees (median of 1.5 degrees vs median of 0.5 degree) and in the extension trial from 40 degrees (median of 1.0 degree vs median of 0.5 degree) than the asymptomatic patients. No differences were found in the other threshold tests, active or visual reproduction tests. CONCLUSIONS: Patients with severe symptoms related to ACL deficiency were found to have inferior proprioceptive ability in some measurements compared with patients with a good knee function. The findings indicate that proprioceptive deficits might influence the outcome of an ACL injury treated nonoperatively.

Adult↗
PubMedDate not supplied

[Brachial presentation of spinal pseudochoreoathetosis. The result of proprioceptive information being processed in parallel].

INTRODUCTION: The term pseudochoreoathetosis is used to refer to the choreoathetoid movements that are produced by alterations in the proprioceptive sensitivity due to damage it has suffered at some point along its course. Proprioceptive sensitivity is considered to go up as far as the cortex along the posterior cords of the spinal cord, which means that if they are injured in the cervical region there should be a sensory deficit in both the upper (UL) and lower limbs (LL). CASE REPORTS: We describe five cases of transverse myelitis with localised cervical injury that selectively and mainly affected the posterior cords of the spinal cord. In the five patients there was selective involvement of the proprioceptive sensitivity in the UL respecting the LL and pseudochoreoathetoid movements of the limb that has been deafferented for proprioceptive sensitivity. The dissociation between the UL and the LL occurs because the spinocerebellar and spinocervical tracts take the proprioceptive information from the LL in parallel to the posterior cords, which receive the proprioceptive sensitivity from the UL. CONCLUSIONS: At present, the most widely accepted physiopathological mechanism explaining pseudochoreoathetosis consists in a failure in the integration of the sensory-motor afferences in the striatum, which causes faulty sensory-motor integration at this level and gives rise to pseudochoreoathetosis.

Adolescent↗
PubMed1994

Shoulder proprioception. Effect of joint laxity, joint position, and direction of motion.

Recently, considerable importance has been ascribed to that portion of shoulder stability which may be provided by active muscle forces. Joint proprioception likely has a considerable role in muscular stabilization of the shoulder by providing information to the central nervous system for the management of muscular activity. Normal human shoulder proprioception has not yet been thoroughly characterized. We have measured shoulder joint proprioception in a population of subjects without known shoulder abnormalities by quantifying the subjects' ability to correctly detect passive shoulder rotation in the abducted shoulder. We have found absolute angular proprioception to range from an average "best" of 0.78 degrees to a "worst" of 1.08 degrees. Individuals who have clinically determined generalized joint laxity are significantly less sensitive in proprioception (P < .002). Detection of external rotation is significantly more sensitive than detection of internal rotation (P < .001). Detection of external rotation becomes significantly more sensitive as the limit of external rotation is approached. We have concluded that these findings suggest capsular tightening as one possible mechanism for shoulder proprioception.

Adult↗
PubMed1996

Proprioception of knee joints with a lesion of the medial meniscus.

We assessed knee-joint proprioception in 23 patients with an isolated lesion of the medial meniscus. Thirteen patients were tested prior to their arthroscopic operation, and 10 patients were examined after partial arthroscopic resection of the injured meniscus. As a control group we evaluated 30 healthy volunteers with clinically normal knee joints. For documentation of the proprioceptive capabilities we performed a special angle reproduction test which was described in the literature. Additionally the subjects were tested with and without a knee bandage, to test its influence on knee-joint proprioception. Our results showed that preoperatively a significant deterioration in proprioception was present compared with the control group. We could not find any influence of the knee bandage on the proprioception of the injured knee. The postoperative group of patients showed a significantly better proprioceptive capability compared to the preoperative patients. The postoperative results also did not show any significant difference as compared to those of the control group.

Adult↗
PubMed2001

Proprioception in Parkinson's disease is acutely depressed by dopaminergic medications.

OBJECTIVES: Impaired proprioception has been previously reported in patients with Parkinson's disease. It was hypothesised that dopaminergic medications transiently depress proprioception, with amplification of adventitious movements as a result. This study tested for effects on proprioception of dopaminergic drugs, and for associations between such effects and drug induced dyskinesias. METHODS: In 17 patients with Parkinson's disease, arm proprioception was tested in the practically defined "off" state, and retested 1 hour after taking levodopa or dopamine agonist. Testing consisted of side to side comparison of elbow angle, matching the contralateral elbow angle, and spatial recall of an unrestrained arm. RESULTS: Proprioception deteriorated as hypothesised, reaching significance by one tailed t test for each of the three tasks. The relative deterioration (and the 95% lower confidence bound for estimated deterioration) was 31% (4%) for side to side elbow comparison, was 27% (11%) for accuracy in matching the contralateral elbow angle, and was 11% (0%) for spatial recall. Dyskinetic (n=6) and non-dyskinetic (n=11) patients did not differ significantly in these effects on proprioception. Control subjects (n=6) and untreated parkinsonian subjects (n=5) did not significantly differ from the parkinsonian patients in the off state. CONCLUSIONS: Administration of levodopa and dopamine agonists were associated with a modest acute suppression in central responsiveness to joint position. It is speculated that compensatory exaggerated movement could account in part for the phenomenon of drug induced dyskinesias.

Acute Disease↗