Cerebellar nuclear cell activity during antagonist cocontraction and reciprocal inhibition of forearm muscles

1985 ◽  
Vol 54 (2) ◽  
pp. 231-244 ◽  
Author(s):  
R. Wetts ◽  
J. F. Kalaska ◽  
A. M. Smith
Keyword(s):  
Activity Patterns ◽  
Cell Activity ◽  
Reciprocal Inhibition ◽  
Discharge Frequency ◽  
Wrist Flexion ◽  
Wrist Movement ◽  
Forearm Muscles ◽  
Flexion Extension ◽  
Nuclear Cell ◽  
Low Order

Monkeys were trained to exert a maintained isometric pinch with the thumb and forefinger. This task reliably elicited a simultaneous cocontraction of the forearm muscles. The same monkeys were also taught to insert the open hand into a manipulandum, flex and extend the wrist 35 and 15 degrees, respectively, and maintain an isometric wrist position against a mechanical stop for 1 s. This second task comprised two conditions: a dynamic or movement phase and a static or isometric phase. Movement always involved a wrist displacement of 50 degrees. Although some forearm muscles demonstrated bidirectional activity during the wrist displacement phase, all the wrist and finger muscles were alternatively active in isometric flexion or extension. Of the neurons in the dentate and interposed nuclei that consistently changed discharge during repeated isometric prehension, over 90% (61/67) of the neurons increased activity during this cocontraction of forearm muscles. About 70% (47/67) of these same nuclear cells discharged with a reciprocal pattern of firing during alternating wrist flexion-extension movements. Forty-six neurons had sustained and reciprocal discharge during the maintained isometric wrist postures. No differences were seen between the activity patterns of dentate and interposed cells with respect to either the prehension task or the reciprocal wrist-movement task. The discharge frequency of some dentate and interpositus neurons could be correlated with prehensile force as well as velocity of wrist movement and torque developed by wrist muscles. Correlation coefficients were calculated between nuclear cell discharge and the amplitude of the surface EMGs of the flexors and extensors of the wrist and fingers during the wrist-movement task. Sixteen nuclear cells showed low-order, but reliably positive, correlations with one of the two forearm muscle groups (mean r = 0.33). In contrast, a sample of seven Purkinje cells recorded during the same task demonstrated low-order correlations that were negative in sign (mean r = -0.30) between discharge frequency and one of the two forearm EMGs.

Cerebellar cortical activity during antagonist cocontraction and reciprocal inhibition of forearm muscles

1984 ◽  
Vol 51 (1) ◽  
pp. 32-49 ◽  
Author(s):  
R. C. Frysinger ◽  
D. Bourbonnais ◽  
J. F. Kalaska ◽  
A. M. Smith
Keyword(s):  
Purkinje Cells ◽  
Cerebellar Cortex ◽  
Discharge Frequency ◽  
Wrist Movement ◽  
Movement Velocity ◽  
Wrist Position ◽  
Forearm Muscles ◽  
Antagonist Muscles ◽  
Primary Fissure ◽  
Flexion And Extension

Monkeys were trained to perform a maintained isometric grip of the thumb and forefinger that elicited a simultaneous cocontraction of the antagonist muscles of the forearm. The same monkeys were also trained to flex and extend the wrist against a stop with the fingers extended and to maintain an isometric wrist position for 1.0-1.5 s. During wrist movement, some of the synergist forearm muscles contracted during both flexion and extension. However, during the maintained isometric wrist position, the prime mover and synergist muscles were reciprocally active or silent. In the culmen-simplex region of the cerebellar cortex bordering on the primary fissure, 62% of the Purkinje cells that were identified by the climbing fiber discharge and that changed firing frequency decreased activity during maintained prehension. Almost all of these same Purkinje cells were reciprocally active during isometric wrist flexion and extension, although three neurons had similar discharge patterns during movements in both directions. In contrast, 79% of the unidentified neurons recorded from the same region of the cerebellar cortex increased discharge frequency during prehension. In general, most of these same neurons had reciprocal patterns of discharge during wrist movement even though a few cells were active during the dynamic phase in both directions. Together, the Purkinje cells and the unidentified neurons with bidirectional response patterns were thought to be related to muscles active during both flexion and extension wrist movements. No cells were found that increased discharge with the static isometric wrist torque exerted in both directions. The discharge frequency of some Purkinje and some unidentified neurons could be shown to be related to prehensile force as well as wrist movement velocity and isometric wrist torque. These data suggest that the discharge of about two-thirds of the Purkinje cells related to forearm muscles located along the borders of the primary fissure may depend on whether antagonist muscles are activated reciprocally or coactively. As a consequence, these cells may play a role in the selection or alternation between either of these two modes of muscular contraction. The increased discharge of the remaining one-third of the Purkinje cells excited during antagonist coactivation may provide inhibition of nuclear cells to stabilize the posture at joints other than the wrist and fingers or, alternatively, they may act to reduce nuclear cell discharge in proportion to the intensity of cutaneous stimulation.

scholarly journals “Taking action” to reduce pain—Has interpretation of the motor adaptation to pain been too simplistic?

PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0260715
Author(s):  
Michael Bergin ◽  
Kylie Tucker ◽  
Bill Vicenzino ◽  
Paul W. Hodges
Keyword(s):  
Noxious Stimulus ◽  
Control Group ◽  
Movement Variability ◽  
Wrist Flexion ◽  
Wrist Movement ◽  
Experimental Conditions ◽  
Stimulus Movement ◽  
Pain Provocation ◽  
Flexion Extension ◽  
Taking Action

Movement adapts during acute pain. This is assumed to reduce nociceptive input, but the interpretation may not be straightforward. We investigated whether movement adaptation during pain reflects a purposeful search for a less painful solution. Three groups of participants performed two blocks (Baseline, Experimental) of wrist movements in the radial-ulnar direction. For the Control group (n = 10) both blocks were painfree. In two groups, painful electrical stimulation was applied at the elbow in Experimental conditions when the wrist crossed radial-ulnar neutral. Different stimulus intensities were given for specific wrist angles in a secondary direction (flexion-extension) as the wrist passed radial-ulnar neutral (Pain 5–1 group:painful stimulation at ~5 or ~1/10—n = 21; Pain 5–0 group:~5 or 0(no stimulation)/10—n = 6)). Participants were not informed about the less painful alternative and could use any strategy. We recorded the percentage of movements using the wrist flexion/extension alignment that evoked the lower intensity noxious stimulus, movement variability, and change in wrist/forearm alignment during pain. Participants adapted their strategy of wrist movement during pain provocation and reported less pain over time. Three adaptations of wrist movement were observed; (i) greater use of the wrist alignment with no/less noxious input (Pain 5–1, n = 8/21; Pain 5–0, n = 2/6); (ii) small (n = 9/21; n = 3/6) or (iii) large (n = 4/21; n = 1/6) change of wrist/forearm alignment to a region that was not allocated to provide an actual reduction in noxious stimulus. Pain reduction was achieved with “taking action” to relieve pain and did not depend on reduced noxious stimulus.

Scaphoid Motion of the Wrist with Scapho-trapezio-trapezoidal Osteoarthritis-A Pilot Study

2020 ◽  
Vol 16 (3) ◽  
pp. 206-209
Author(s):  
Ronit Wollstein ◽  
Hisao Moritomo ◽  
Iida Akio ◽  
Shohei Omokawa
Keyword(s):  
Neutral Position ◽  
Wrist Flexion ◽  
Wrist Movement ◽  
Ulnar Deviation ◽  
Wrist Motion ◽  
3 Dimensional ◽  
Active Flexion ◽  
Extended Position ◽  
Flexion Extension ◽  
Surface Models

Background: The purpose of this study was to investigate scaphoid motion within the scapho-trapezio-trapezoidal (STT) joint during wrist motion in the presence of STT joint osteoarthritis (OA). Methods: We studied 11 wrists with STT OA and 5 normal wrists. Computed tomography (CT) images were acquired in five wrist positions (maximum active flexion, extension, radial deviation, ulnar deviation, and neutral position). The 3-dimensional surface models of the radius and scaphoid were constructed and the motion of scaphoid relative to the radius was calculated. Results and Conclusion: During wrist flexion/extension motion, the scaphoid rotated mostly in the flexion/extension plane. The angle tended to be smaller in STT OA than in normal. During wrist radioulnar deviation, the scaphoid was in an extended position in neutral wrist in STT OA. The motion of scaphoid in STT OA was divided into two types: a rigid type and mobile type. The mobile type rotated closer to the flexion/extension plane than the rigid type. Taking into account scaphoid motion during wrist movement before surgery may provide better results in the treatment of STT OA.

scholarly journals Design and Development of Continuous Passive Motion (CPM) for Fingers and Wrist Grounded-Exoskeleton Rehabilitation System

2021 ◽  
Vol 11 (2) ◽  
pp. 815
Author(s):  
Husam Almusawi ◽  
Géza Husi
Keyword(s):  
Experimental Testing ◽  
Hand Movement ◽  
Evaluation Process ◽  
Continuous Passive Motion ◽  
Wrist Flexion ◽  
Design And Development ◽  
Passive Motion ◽  
Assistive Robots ◽  
Flexion Extension ◽  
Design Characteristics

Impairments of fingers, wrist, and hand forearm result in significant hand movement deficiencies and daily task performance. Most of the existing rehabilitation assistive robots mainly focus on either the wrist training or fingers, and they are limiting the natural motion; many mechanical parts associated with the patient’s arms, heavy and expensive. This paper presented the design and development of a new, cost-efficient Finger and wrist rehabilitation mechatronics system (FWRMS) suitable for either hand right or left. The proposed machine aimed to present a solution to guide individuals with severe difficulties in their everyday routines for people suffering from a stroke or other motor diseases by actuating seven joints motions and providing them repeatable Continuous Passive Motion (CPM). FWRMS approach uses a combination of; grounded-exoskeleton structure to provide the desired displacement to the hand’s four fingers flexion/extension (F/E) driven by an indirect feed drive mechanism by adopting a leading screw and nut transmission; and an end-effector structure to provide angular velocity to the wrist flexion/ extension (F/E), wrist radial/ulnar deviation (R/U), and forearm supination/pronation (S/P) driven by a rotational motion mechanism. We employed a single dual-sided actuator to power both mechanisms. Additionally, this article presents the implementation of a portable embedded controller. Moreover, this paper addressed preliminary experimental testing and evaluation process. The conducted test results of the FWRMS robot achieved the required design characteristics and executed the motion needed for the continuous passive motion rehabilitation and provide stable trajectories guidance by following the natural range of motion (ROM) and a functional workspace of the targeted joints comfortably for all trainable movements by FWRMS.

Quantification of Hand Grip Force under Dynamic Conditions

1993 ◽  
Vol 37 (10) ◽  
pp. 715-719 ◽  
Author(s):  
Katherine R. Lehman ◽  
W. Gary Allread ◽  
P. Lawrence Wright ◽  
William S. Marras
Keyword(s):  
Grip Force ◽  
Wrist Flexion ◽  
Range Of Movement ◽  
Ulnar Deviation ◽  
Dynamic Conditions ◽  
Radial Deviation ◽  
Hand Grip ◽  
Flexion Extension ◽  
Maximum Grip ◽  
Lower Grip

A laboratory experiment was conducted to determine whether grip force capabilities are lower when the wrist is moved than in a static position. The purpose was to determine the wrist velocity levels and wrist postures that had the most significant effect on grip force. Maximum grip forces of five male and five female subjects were determined under both static and dynamic conditions. The dominant wrist of each subject was secured to a CYBEX II dynamometer and grip force was collected during isokinetic wrist deviations for four directions of motion (flexion to extension, extension to flexion, radial to ulnar, and ulnar to radial). Six different velocity levels were analyzed and grip forces were recorded at specific wrist positions throughout each range of movement. For flexion-extension motions, wrist positions from 45 degrees flexion to 45 degrees extension were analyzed whereas positions from 20 degrees radial deviation to 20 degrees ulnar deviation were studied for radial-ulnar activity. Isometric exertions were also performed at each desired wrist position. Results showed that, for all directions of motion, grip forces for all isokinetic conditions were significantly lower than for the isometric exertions. Lower grip forces were exhibited at extreme wrist flexion and extreme radial and ulnar positions for both static and dynamic conditions. The direction of motion was also found to affect grip strength; extension to flexion exertions produced larger grip forces than flexion to extension exertions and radial to ulnar motion showed larger grip forces than ulnar to radial deviation. Although, males produced larger grip forces than females in all exertions, significant interactions between gender and velocity were noted.

Arthroscopic ligament-specific repair for triangular fibrocartilage complex foveal avulsions: a minimum 2-year follow-up study

2020 ◽  
pp. 175319342095790
Author(s):  
Bo Liu ◽  
Margareta Arianni ◽  
Feiran Wu
Keyword(s):  
Patient Reported Outcomes ◽  
Triangular Fibrocartilage Complex ◽  
Wrist Flexion ◽  
Level Of Evidence ◽  
Flexion Extension ◽  
Patient Reported ◽  
Triangular Fibrocartilage ◽  
The Mean ◽  
Viable Method

This study reports the arthroscopic ligament-specific repair of the triangular fibrocartilage complex (TFCC) that anatomically restores both the volar and dorsal radioulnar ligaments into their individual foveal footprints. Twenty-five patients underwent arthroscopic ligament-specific repair with clinical and radiological diagnoses of TFCC foveal avulsions. The mean age was 28 years (range 14–47) and the mean follow-up was 31 months (range 24–47). Following arthroscopic assessment, 20 patients underwent double limb radioulnar ligament repairs and five had single limb repairs. At final follow-up, there were significant improvements in wrist flexion–extension, forearm pronation–supination and grip strength. There were also significant improvements in pain and patient-reported outcomes as assessed by the patient-rated wrist evaluation, Disabilities of the Arm, Shoulder and Hand score and modified Mayo wrist scores. Arthroscopic ligament-specific repair of the TFCC does not require specialist dedicated equipment or consumables and offers a viable method of treating these injuries. Level of evidence: IV

Outcomes of Supplementary Spring Wire Fixation With Volar Plating for Volar Lunate Facet Fragments in Distal Radius Fractures

Hand ◽  
2020 ◽  
pp. 155894472097640
Author(s):  
Nathaniel Fogel ◽  
Lauren M. Shapiro ◽  
Allison Roe ◽  
Sahitya Denduluri ◽  
Marc J. Richard ◽  
...  
Keyword(s):  
Distal Radius ◽  
Distal Radius Fractures ◽  
Wrist Flexion ◽  
Volar Plating ◽  
Radius Fractures ◽  
Locked Plating ◽  
Spring Wire ◽  
Flexion Extension ◽  
Wire Fixation ◽  
The Mean

Background Intra-articular distal radius fractures with small volar lunate facet fragments can be challenging to address with volar plate fixation alone. Volar locked plating with supplementary spring wire fixation has been previously described in a small series but has not been further described in the literature. We hypothesized that this technique can provide adequate fixation for volar lunate facet fragments smaller than 15 mm in length, which are at risk of displacement. Methods We completed a retrospective chart review (2015-2019) of patients who underwent volar locked plating with the addition of supplementary spring wire fixation for intra-articular distal radius fractures with a volar lunate facet fragment (<15 mm). Postoperative radiographs were assessed to evaluate union, evidence of hardware failure, escape of the volar lunate facet fragment, and postoperative volar tilt. Clinical outcome was assessed with wrist flexion/extension, arc of pronosupination, and Quick Disabilities of the Arm, Shoulder, and Hand Score ( QuickDASH) scores. Results Fifteen patients were identified, of which all went on to fracture union. There were no hardware failures or escape of the volar lunate facet fragment at final follow-up. One patient underwent hardware removal for symptoms of flexor tendon irritation. The mean wrist flexion was 59°, wrist extension was 70°, pronation was 81°, and supination was 76°. The mean QuickDASH score was 18.5. The mean postoperative volar tilt was 3.6°. Conclusions Supplementary spring wire fixation with standard volar plating provides stable fixation for lunate facet fragments less than 15 mm. This technique is a safe and reliable alternative to commercially available fragment-specific implants.

Re-motion total wrist arthroplasty: 39 non-rheumatoid cases with a mean follow-up of 7 years

2019 ◽  
Vol 44 (9) ◽  
pp. 946-950 ◽  
Author(s):  
Stefan M. Froschauer ◽  
Maximilian Zaussinger ◽  
Dietmar Hager ◽  
Manfred Behawy ◽  
Oskar Kwasny ◽  
...  
Keyword(s):  
Radial Component ◽  
Visual Analogue Scale Pain ◽  
Wrist Flexion ◽  
Level Of Evidence ◽  
Pain Scores ◽  
Total Wrist Arthroplasty ◽  
Flexion Extension ◽  
Analogue Scale Pain ◽  
Wrist Arthroplasty

We evaluated the outcomes of the Re-motion total wrist arthroplasty in 39 non-rheumatoid patients. The mean follow-up was 7 years (range 3–12). Postoperative wrist flexion-extension and radial-ulnar deviation as well as the scores of the Disability of Arm Shoulder and Hand questionnaire and the visual analogue scale pain scores improved significantly. Complications occurred in 13 wrists, five of which required further surgery. The most frequent complication was impingement between the scaphoid and the radial implant (n = 5), which can be avoided by complete or almost complete scaphoid resection. Periprosthetic radiolucency developed around the radial component in three cases and three radial screws loosened. Despite the incidence of high implant survival in 38 of 39 wrists over 7 years (97%), the complication rate is not satisfying. Knowledge of the risk of complications and patient selection are essential when making the decision to choose wrist arthroplasty over arthrodesis. Level of evidence: IV

Activity of precentral neurons during torque-triggered hand movements in awake primates

1979 ◽  
Vol 57 (2) ◽  
pp. 174-184 ◽  
Author(s):  
Y. C. Wong ◽  
H. C. Kwan ◽  
J. T. Murphy
Keyword(s):  
Wrist Joint ◽  
Wrist Flexion ◽  
Somatosensory Stimulation ◽  
Sensory Stimuli ◽  
Neuronal Populations ◽  
Supportive Role ◽  
Flexion Extension ◽  
Cortical Responses ◽  
Early Portion ◽  
Temporally Correlated

In monkeys performing a handle-repositioning task involving primarily wrist flexion–extension (F–E) movements after a torque perturbation was delivered to the handle, single units were recorded extracellularly in the contralateral precentral cortex. Precentral neurons were identified by passive somatosensory stimulation, and were classified into five somatotopically organized populations. Based on electromyographic recordings, it was observed that flexors and extensors about the wrist joint were specifically involved in the repositioning of the handle, while many other muscles which act at the wrist and other forelimb joints were involved in the task in a supportive role. In precentral cortex, all neuronal responses observed were temporally correlated to both the sensory stimuli and the motor responses. Visual stimuli, presented simultaneously with torque perturbations, did not affect the early portion of cortical responses to such torque perturbations. In each of the five somatotopically organized neuronal populations, task-related neurons as well as task-unrelated ones were observed. A significantly larger proportion of wrist (F–E) neurons was related to the task, as compared with the other, nonwrist (F–E) populations. The above findings were discussed in the context of a hypothesis for the function of precentral cortex during voluntary limb movement in awake primates. This hypothesis incorporates a relationship between activities of populations of precentral neurons, defined with respect to their responses to peripheral events at or about single joints, and movements about the same joint.

Clinical outcomes of proximal row carpectomy versus four-corner arthrodesis for post-traumatic wrist arthropathy: a systematic review

2014 ◽  
Vol 40 (5) ◽  
pp. 450-457 ◽  
Author(s):  
B. M. Saltzman ◽  
J. M. Frank ◽  
W. Slikker ◽  
J. J. Fernandez ◽  
M. S. Cohen ◽  
...  
Keyword(s):  
Systematic Review ◽  
Grip Strength ◽  
Complication Rate ◽  
Contralateral Side ◽  
Wrist Flexion ◽  
Proximal Row Carpectomy ◽  
Non Union ◽  
Radial Deviation ◽  
Hand Grip ◽  
Flexion Extension

We conducted a systematic review of studies reporting clinical outcomes after proximal row carpectomy or to four-corner arthrodesis for scaphoid non-union advanced collapse or scapholunate advanced collapse arthritis. Seven studies (Levels I–III; 240 patients, 242 wrists) were evaluated. Significantly different post-operative values were as follows for four-corner arthrodesis versus proximal row carpectomy groups: wrist extension, 39 (SD 11º) versus 43 (SD 11º); wrist flexion, 32 (SD 10º) versus 36 (SD 11º); flexion-extension arc, 62 (SD 14º) versus 75 (SD 10º); radial deviation, 14 (SD 5º) versus 10 (SD 5º); hand grip strength as a percentage of contralateral side, 74% (SD 13) versus 67% (SD 16); overall complication rate, 29% versus 14%. The most common post-operative complications were non-union (grouped incidence, 7%) after four-corner arthrodesis and synovitis and clinically significant oedema (3.1%) after proximal row carpectomy. Radial deviation and post-operative hand grip strength (as a percentage of the contralateral side) were significantly better after four-corner arthrodesis. Four-corner arthrodesis gave significantly greater post-operative radial deviation and grip strength as a percentage of the opposite side. Wrist flexion, extension, and the flexion-extension arc were better after proximal row carpectomy, which also had a lower overall complication rate. Level of evidence: Level III (Level I-III studies), Systematic Review. Therapeutic.

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