Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Hand”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,189 records · Page 66Linked to original sources
PubMed2001

Between-species variation in the development of hand preference among macaques.

This research examined between-species variation in the development of hand preference among Macaca. Specifically, we examined hand preference using juveniles and adults of three macaque species that differ in social and reactive tendencies in order to examine whether the correlation between temperament and handedness that has been noted within Macaca mulatta occurs between closely related species. Each of the species studied exhibited a different pattern of hand preference development. Both juvenile and adult M. mulatta exhibited group-level left-hand bias. Juvenile Macaca nemestrina were not biased towards either hand at the group-level, whereas adults exhibited a group-level left-hand bias. Neither juvenile nor adult Macaca fascicularis exhibited manual bias at the group-level. Analysis of variance indicated statistically significant main effects of species and age class on hand preference measures. Post-hoc analysis indicated greater use of the left- versus right-hand, and greater hand preference strength independent of direction, among M. mulatta and M. nemestrina than among M. fascicularis, and among adults than among juveniles. These results indicate significant between-species variation in the development of hand preference within the genus Macaca, and are inconsistent with any one single-factor theory yet offered to explain the etiology of primate laterality. We hypothesize that the relationship between handedness and temperament that has been shown within M. mulatta may generalize across closely related primate species.

Age Factors↗
PubMed2000

Development of hand preferences in marmosets (Callithrix jacchus) and effects of aging.

The authors investigated the development of unimanual hand use and hand preferences during feeding in 15 marmosets (Callithrix jacchus), ages birth to 51-70 months. Bimanual hand use was common at 1-2 months, but by 5-8 months unimanual holding had developed and so had significant hand preferences. Half of the marmosets preferred to pick up and take food to the mouth with the left hand, and half preferred the right hand. Individuals maintained the same hand preference at all ages examined. Significant relationships were also found between the postures adopted during feeding and the direction of hand preferences displayed by juvenile marmosets. There was a positive correlation between increased suspension and increased left-hand preference, and a negative correlation between increased feeding in a tripedal posture and increased left-hand preference. These results are discussed in terms of motor development and hemispheric specialization.

Aging↗
PubMed1999

Advancement in the zone of calcified cartilage in osteoarthritic hands of patients detected by high definition macroradiography.

OBJECTIVE: High definition macroradiography permits the advancement in the zone of calcified cartilage (described as a ZCC step) to be detected in osteoarthritic (OA) hand joints of patients. The pattern of their incidence and distribution was determined and compared to the joint space width (JSW) measurement. DESIGN: Macroradiographs, x5 magnification, were obtained of the OA hands of 44 patients at baseline and at 18 months. The incidence of ZCC steps, identified as an advancement in the mineralized cartilage front into articular cartilage, was assessed at each articular surface. JSW was measured and was used to determine the difference in JSW between hands and groups of joints with and without ZCC steps at both X-ray visits. RESULTS: ZCC steps were only found at the convex articular surfaces in 42 (48%) of hand joints in 28 (64%) patients. Here, ZCC steps were present in 36 joints in the non-dominant hand compared to 30 joints in the dominant hand. In the former, they were present in 22 DIP, six PIP and eight MCP joints and in 12 DIP, 8 PIP and 10 MCP joints in the dominant hand. By 18 months new ZCC steps had formed in 15 hands with and 17 hands without previous ZCC steps. At both X-ray visits no statistically significant difference in JSW was found between the hands and joint groups with and without ZCC steps. CONCLUSION: Although ZCC steps and JSW loss were greater at the PIP joints, supporting a mechanical hypothesis for ZCC formation, their presence in joints, where JSW was larger, and their greater incidence in the non-dominant PIP joints, suggest that factors associated with vascular changes, related to subchondral bone remodeling, are responsible.¿copy¿

Aged↗
PubMed2002

Elbow load with various forearm positions during one-handed pushup exercise.

This is the first study of the one-handed pushup, and tries to show the effects of forearm rotations. Previous studies of elbow loading have focused on passive loading and small loads, because data from large loads during active exercise is not easy to obtain. In order to investigate the biomechanical impact of hand position on the elbow and the potential trauma mechanisms of outstretched elbow, joint loading across the elbow was analyzed for three forearm rotational positions, neutral, 90 degrees internal rotation and 90 degrees external rotation. Both kinematic and kinetic data were collected from eight volunteers by the Motion Analysis System and a Kistler Force Plate. Statistical analysis of the data delineates the relationship between elbow joint load and hand rotational position during one-handed pushup, and also provides useful biomechanical information for this challenging exercise. The axial and valgus stresses and forces are the major concerns. The peak axial forces exerted on the elbow joint averaged 65 % of the body weight when the hand position was neutral, and was significantly reduced with the hand rotated either internally or externally. The peak valgus shear force with the hand externally rotated was 50 % greater than the other two positions. Thus, outward rotation of the hand is a stressful position that should be avoided during one-handed pushup exercise or forward falls with outstretched hands in order to reduce the risk of elbow injuries.

Adolescent↗
PubMed2000

Calcium affinity, cooperativity, and domain interactions of extracellular EF-hands present in BM-40.

The structure and function of cytosolic Ca(2+)-binding proteins containing EF-hands are well understood. Recently, the presence of EF-hands in an extracellular protein was for the first time proven by the structure determination of the EC domain of BM-40 (SPARC (for secreted protein acidic and rich in cysteine)/osteonectin) (Hohenester, E., Maurer, P., Hohenadl, C., Timpl, R., Jansonius, J. N., and Engel, J. (1996) Nat. Struct. Biol. 3, 67-73). The structure revealed a pair of EF-hands with two bound Ca(2+) ions. Two unusual features were noted that distinguish the extracellular EF-hands of BM-40 from their cytosolic counterparts. An insertion of one amino acid into the loop of the first EF-hand causes a variant Ca(2+) coordination, and a disulfide bond connects the helices of the second EF-hand. Here we show that the extracellular EF-hands in the BM-40 EC domain bind Ca(2+) cooperatively and with high affinity. The EC domain is thus in the Ca(2+)-saturated form in the extracellular matrix, and the EF-hands play a structural rather than a regulatory role. Deletion mutants demonstrate a strong interaction between the EC domain and the neighboring FS domain, which contributes about 10 kJ/mol to the free energy of binding and influences cooperativity. This interaction is mainly between the FS domain and the variant EF-hand 1. Certain mutations of Ca(2+)-coordinating residues changed affinity and cooperativity, but others inhibited folding and secretion of the EC domain in a mammalian cell line. This points to a function of EF-hands in extracellular proteins during biosynthesis and processing in the endoplasmic reticulum or Golgi apparatus.

Amino Acid Motifs↗
PubMed1996

Trunk kinematics of one-handed lifting, and the effects of asymmetry and load weight.

This study investigated trunk kinematic differences between lifts performed using either one hand (unsupported) or two hands. These effects were studied while beginning the lifts from different asymmetric starting positions and while lifting different load weights. Each subject lifted a box from a lower to an upper platform under one- and two-handed lifting conditions. Subjects wore a lumbar spine electrogoniometer, from which relative motion components were calculated in the trunk's three cardinal planes. Results of this study showed that one-handed lifting resulted in significantly higher ranges of motion in the lateral and transverse planes and greater flexion in the sagittal plane. Back motion characteristics previously found to be associated with low back disorders were all significantly higher for one-handed lifts. The two-handed lift technique, on the other hand, produced overall faster trunk motions in the sagittal plane and equal or larger acceleration and deceleration magnitudes in all planes of motion. Increases in load asymmetry affected trunk kinematics, in that magnitude values for range of motion, velocity and acceleration became much greater with increasingly asymmetric load positions. Increasing the load weight appeared to have less of an effect on trunk kinematics, with increases in position mostly occurring during sagittal and lateral bending. These results suggest that unsupported one-handed lifting loads the spine more than two-handed lifts, due to the added coupling. Applying these results to a previously developed model, one-handed lifting was also found to increase one's risk of suffering a low back disorder.

Adult↗
PubMed2002

Direction of hand preference: the connection with speech and the influence of familial handedness.

Taking familial handedness into account, right- and left-handers with differing degrees of hand preference were monaurally presented with verbal stimuli (CVs) to which they responded using their right and left hands at separate times. This reaction time design was used to ascertain the relative cognitive functioning capacity of each hemisphere for verbal processing. However, the results disclosed more about the determination of direction of hand preference than about cognitive processing, per se. It was found that in both strong right-handers and strong left-handers with an incongruent hand preference (i.e., own handedness incongruent with family history of handedness) direction of hand preference is the result of suppression of the nonpreferred hand in the left hemisphere. Strong right- and strong left-handers with a congruent hand preference (i.e., hand preference congruent with family history of handedness) appear to have a more direct hand preference-left hemisphere mechanism. The findings of the present study are used to form part of a new theory of hand preference determination.

Adult↗
PubMed2004

Hand preference survey of 5136 school children in Western Uganda.

Few handedness studies have been conducted with African populations. Our preliminary survey of 5136 primary school students from 16 schools in Western Uganda (age range: 4 to 19 years old) found that 4.8% (n = 248) wrote left-handed. Of the 248 left-handed writers, there were more males (57.3%, n = 141) than females (42.7%, n = 105). The average frequency of left-handed writing in males was 5.6%, while the average for females was 4%. Of the 24 primary school teachers we interviewed, half (n = 12) expressed no desire to have left-handed students switch to writing right-handed, and 29% (n = 7) advised left-handed students to write with their right hands, but did not insist upon their doing so. Only 17% (n = 4) could be described as strongly urging left-handed students to switch writing hands, with one comment (4%) not applicable. While handedness is not defined by a single manual activity (especially one sensitive to social pressure), this survey documents the incidence of left-handed writing among primary school children of Western Uganda.

Adolescent↗
PubMed1999

Tactile evaluation of fade of the train-of-four and double-burst stimulation using the anaesthetist's non-dominant hand.

We have studied detection of fade in response to train-of-four (TOF), double-burst stimulation3,3 (DBS3,3) or DBS3,2, assessed tactilely by the anaesthetist using the index finger of the non-dominant hand and the thumb of the patient, compared with that assessed when the index finger of the dominant hand was used. The probability of detection of any fade in response to TOF or DBS3,3 using the non-dominant hand was significantly less than when the dominant hand was used (P < 0.05). The probability of identification of fade in response to DBS3,2 assessed using the non-dominant hand was comparable with that evaluated using the dominant hand when TOF ratios were 0-0.9, but when TOF ratios reached 0.91-1.00, detection using the non-dominant hand was significantly less common than with the dominant hand (12% vs 33%; P < 0.05). Using the non-dominant hand, the probability of detection of fade in response to ulnar nerve stimulation was less than that with the dominant hand and only the absence of DBS3,2 fade ensured sufficient recovery of neuromuscular block.

Adult↗
PubMed2006

Knowledge in the Palm of your hands: PDAs in the clinical setting.

OBJECTIVE: To explore the impact of hand-held computers on patient care by identifying: (i) how often clinical staff accessed resources on hand-held computers to inform their clinical decision making; (ii) Which hand-held resources were thought to be most useful in the clinical setting; (iii) the barriers to using hand-held resources to support patient care. DESIGN: A descriptive study comparing aspects of Personal Digital Assistant (PDA) resource use in two phases, between August 2002 and December 2003. There was variability in the way that resources were accessed between the two studies. SETTING: University Hospitals of Leicester NHS Trust, an acute teaching hospital, and one primary care practice. PARTICIPANTS: A purposive sample of 14 clinical and librarian staff participated in phase one and 14 in phase two of the study. Participants consisted of consultants, nurses, pharmacist, junior doctors, clinical librarians, and a general practitioner. MAIN OUTCOME MEASURES: Baseline Data Questionnaire to identify the participants' level of knowledge and use of hand-helds on entering the study. End-of-phase questionnaire with self-reported measures of use of the hand-held and PDA resources during the study. RESULTS: All of the participants used hand-helds in their clinical setting to support evidence-based practice and education, but with varying frequency. More staff reported using the hand-held to answer specific patient questions in phase two than phase one of the study. UK resources were preferred to American resources. The 'plug-in and go' method using Secure Digital (SD) cards was preferred to downloading resources from the Internet. CONCLUSIONS: Hand-held technology is emerging as an effective clinical tool to aid evidence-based practice and support the educational needs of clinical staff. The hand-held can provide a critical mass of information that is relevant, quickly accessible and in a coherent format: delivering clinical information at the point of need with a resulting benefit to patient safety.

Computer Literacy↗
PubMedDate not supplied

Electromyographic and cinematographic analysis of elbow function in tennis players using single- and double-handed backhand strokes.

It is generally believed that tennis players using a double-handed backhand rarely develop lateral epicondylitis since the helping arm appears to absorb more energy and changes the mechanics of the swing. The purpose of this paper was to compare muscle activity about the elbow in single- and double-handed backhand strokes in competitive tennis players. Muscle activity in 3 elbow extensors, a wrist flexor, and a forearm pronator of the dominant arm was compared during the single-handed (N = 14) and double-handed (N = 13) backhand ground strokes using indwelling electromyography and high-speed cinematography. Significantly higher activity was seen in the double-handed technique in the flexor carpi radialis muscle in the preparation phase and in the pronator teres muscle in the acceleration phase. Higher flexor carpi radialis muscle activity in preparation of the double-handed stroke appeared to be a function of the double-handed grip used on the racquet, and the increased pronator teres muscle activity in acceleration indicated maintenance of greater pronation provided by the grip of the non-dominant hand. The decreased occurrence of lateral epicondylitis in players using a double-handed backhand may not be caused by decreased extensor activity, but rather by factors associated with flawed stroke mechanics more often seen in the single-handed technique.

Elbow↗
PubMed2001

Laparoscopic bilateral hand assisted nephrectomy for autosomal dominant polycystic kidney disease: initial experience.

PURPOSE: The laparoscopic technique for bilateral nephrectomy in patients with autosomal dominant polycystic kidney disease is technically difficult. The procedure may be more acceptable if alterations to the technique made it safer and easier to perform. We describe our initial experience with, and the feasibility and potential benefits of hand assisted laparoscopic nephrectomy for approaching these large kidneys in patients with autosomal dominant polycystic kidney disease. MATERIALS AND METHODS: This approach was successfully applied in 3 patients with end stage renal disease due to autosomal dominant polycystic kidney disease. After obtaining transumbilical pneumoperitoneum ports were placed in the umbilicus (12 mm.), sub-xiphoid in the midline (12 mm.) and subcostal in the midclavicular line on each side (12 mm.). The table was tilted 40 degrees away from the planned side of initial nephrectomy with the patient in the half lateral position. A 7 cm. midline incision was made that incorporated the umbilical port and a commercially available hand assistance device was positioned. One surgeon hand was inserted into the abdomen to serve as a retractor/blunt dissector, while the other operated the electrosurgical instruments. The right hand was inserted for left nephrectomy and the left hand was inserted for right nephrectomy. The laparoscope was passed via the sub-xiphoid port and the instruments were placed through the ipsilateral subcostal laparoscopic port. Nephrectomy was completed and the specimen was removed through the hand port incision by draining the cysts as they were exposed to view via the midline incision. When dissection was difficult, an additional port was placed in the anterior axillary line at the umbilical level. Some cysts were ruptured or aspirated to decrease overall kidney size and make extraction possible via the 6 to 7 cm. midline incision. RESULTS: All procedures were successfully completed. Mean operative time for bilateral hand assisted laparoscopic nephrectomy was 5.5 hours (range 4.5 to 6.6). Estimated blood loss was 200 cc or less. Patients resumed oral intake on postoperative day 1. The mean amount of parenteral analgesics required postoperatively was decreased. Mean hospital stay was 4.3 days but it was 3 days when considering nephrectomy only. Patients returned to normal activity after an average of 2 weeks. There was sustained resolution of preoperative discomfort based on pain analog scales. At 1 month or less all patients recorded absent pain. They uniformly noticed improved preoperative pulmonary and gastrointestinal symptoms CONCLUSIONS: Hand assisted laparoscopic nephrectomy in patients with autosomal dominant polycystic kidney disease makes bilateral nephrectomy a reasonable option. The bilateral procedure may be performed as rapidly as laparoscopic only, unilateral nephrectomy in these cases. The advantages of the hand assisted approach include using tactile sensation to facilitate dissection, rapid blunt finger dissection, hand retraction and the application of immediate tamponade when needed. This procedure provides the benefits of minimal intraoperative blood loss, minimal postoperative pain, brief hospital stay and rapid convalescence in this group of patients at high risk.

Adult↗
PubMed1981

Handedness: coordination of within- and between-hand alternating movements.

Two models of coordination of within- and between-hand alternating movements are compared. Model 1 assumes that control of bimanual movement passes back and forth between two independent systems, each of which guides one hand, and that the performance of alternating tapping movements (e.g., right index, right middle fingers) within a hand is very different from performance of alternating movements between hands (right index, left index fingers). The model suggests that right/left performance asymmetries on given tasks reflect the characteristics of the independent systems and would therefore predict that factor analysis would yield a "hand" factor. Model 2 assumes that a single system initiates and terminates movement in two subsystems, each of which guides one hand, and it suggests that the task of guiding alternating tapping movements within a hand is very similar to the task of alternating movement between hands. Model 2 would not predict an independent "hand" factor in the factor analysis of performances of tasks yielding left/right asymmetries; the asymmetries presumably arise because the single higher order system has better access to one of the subsystems than to the other. Analyses of performance of within- and between-hand alternations, single-finger tapping movements, and a pursuit rotor task in 92 subjects lend clear support to Model 2.

Female↗
PubMed2001

Hand trajectory invariance in reaching movements involving the trunk.

Movements of different body segments may be combined in different ways to achieve the same motor goal. How this is accomplished by the nervous system was investigated by having subjects make fast pointing movements with the arm in combination with a forward bending of the trunk that was unexpectedly blocked in some trials. Subjects moved their hand above the surface of a table without vision from an initial position near the midline of the chest to remembered targets placed within the reach of the arm in either the ipsi- or contralateral workspace. In experiment 1, subjects were instructed to make fast arm movements to the target without corrections whether or not the trunk was arrested. Only minor changes were found in the hand trajectory and velocity profile in response to the trunk arrest, and these changes were seen only late in the movement. In contrast, the patterns of the interjoint coordination substantially changed in response to the trunk arrest, suggesting the presence of compensatory arm-trunk coordination minimizing the deflections from the hand trajectory regardless of whether the trunk is recruited or mechanically blocked. Changes in the arm interjoint coordination in response to the trunk arrest could be detected kinematically at a minimal latency of 50 ms. This finding suggests a rapid reflex compensatory mechanism driven by vestibular and/or proprioceptive afferent signals. In experiment 2, subjects were required, as soon as they perceived the trunk arrest, to change the hand motion to the same direction as that of the trunk. Under this instruction, subjects were able to initiate corrections only after the hand approached or reached the final position. Thus, centrally mediated compensatory corrections triggered in response to the trunk arrest were likely to occur too late to maintain the observed invariant hand trajectory in experiment 1. In experiment 3, subjects produced similar pointing movements, but to a target that moved together with the trunk. In these body-oriented pointing movements, the hand trajectories from trials in which the trunk was moving or arrested were substantially different. The same trajectories represented in a relative frame of reference moving with the trunk were virtually identical. We conclude that hand trajectory invariance can be produced in an external spatial (experiment 1) or an internal trunk-centered (experiment 3) frame of reference. The invariance in the external frame of reference is accomplished by active compensatory changes in the arm joint angles nullifying the influence of the trunk motion on the hand trajectory. We suggest that to make a transition to the internal frame of reference, control systems suppress this compensation. One of the hypotheses opened to further experimental testing is that the integration of additional (trunk) degrees of freedom into movement is based on afferent (proprioceptive, vestibular) signals stemming from the trunk motion and transmitted to the arm muscles.

Abdomen↗
PubMed2004

Bone loss in the contralateral asymptomatic hand in patients with complex regional pain syndrome type 1.

Regional osteoporosis was seen radiographically in clinically affected areas in patients with complex regional pain syndrome type 1 (CRPS1). The aim of the this study was to investigate whether bone loss developed in the contralateral hand in patients with unilateral CRPS1 of the hand. Thirty-two patients with CRPS1 of the hand were included in this study. Bone mineral density was measured in the left proximal femur and both ultradistal radiuses, using dual-energy X-ray absorptiometry. The subjects were classified as grades 1 to 3 according to the T-score of both ultradistal radiuses (densitometric grades): grade 1, both radiuses were normal; grade 2, bone loss was determined only in the affected radius; and grade 3, there was bone loss in both radiuses. Twenty (62.5%) patients had bone loss in the affected hand; 11 patients (34.4%) had bone loss only on the affected side and 9 patients (28.1%) had bone loss on both sides. The mean duration of the period between the diagnosis of the injury and the measurement of bone density was 1.9 +/- 0.6 months in patients with grade 1, 3.1 +/- 1.0 months in patients with grade 2, and 5.5 +/- 2.2 months in patients with grade 3. The Spearman test showed a significant correlation between the period of injury and the densitometric grade ( R = 0.774; P = 0.0001). In conclusion, the current study of patients with CRPS1, showed that the bone loss in the asymptomatic contralateral hand developed at a later stage than that in the affected hand. This bone loss was less frequent and of a lower degree in the asymptomatic contralateral hand than in the affected hand. The bone loss in the asymptomatic contralateral hand could be explained by the loss of sympathetic tone in CRPS1 and contralateral sympathetic innervation.

Absorptiometry, Photon↗
PubMed1995

Do 'chlorine covers' exert a sustained bactericidal effect on the bacterial hand flora?

Treatment of skin with chlorine generates 'chlorine covers' which, in a previous study, exerted significant sustained bactericidal effects against transient skin flora on the upper arm and forearm. In this investigation, this effect was studied on both the transient and resident flora of the hands using test models for the evaluation of hand disinfectants as agreed upon in Austria and Germany. Chlorine covers were generated by bathing hands in a solution of 2% sodium tosylchloramide for 1 min. Subsequently, this cover was destroyed on one, randomly selected, hand by bathing it in a solution of 0.5% sodium thiosulphate for 15 s. The amount of chlorine on the fingertips of chlorinated hands was 2.2 +/- 0.4 micrograms/cm2; that on subsequently dechlorinated hands was 0.2 +/- 0.1 microgram/cm2. In experiments with artificially contaminated hands (Escherichia coli), the kinetics of bacterial die-off were the same on both hands. Also, in experiments with resident flora, the kinetics of bacterial die-off did not suggest bacterial reductions that increase with the duration of contact with the chlorine cover. It was concluded that with the test models used, a significant sustained antimicrobial effect of the chlorine cover could not be demonstrated on hands.

Animals↗
PubMed2006

The effects of glove thickness and work load on female hand performance and fatigue during a infrequent high-intensity gripping task.

In various workplaces, gloves are commonly employed to protect the hands with the design rationale of 'the thicker the gloves, the better the protection'. Therefore, the present paper investigated the effects of glove thickness on hand performance and fatigue during two infrequent high-intensity gripping tasks, such as 5-s and sustained tasks. The hand performance was evaluated by maximum volitional contraction (MVC) and its associated time needed to reach the MVC (TMVC), and the total force generation (TFG) during the sustained task. The hand fatigue was assessed by MVC degeneration (DeltaMVC), the shift in time needed to reach the MVC (DeltaTMVC), and the maximal endurance time (MET) associated with the sustained task. Ten female subjects took part in the experiment voluntarily. The four-gloved conditions included bare hand, wearing one layer (Cotton-1), wearing two layers of cotton gloves (Cotton-2), and covering the handle with two layers of cotton glove and exerting with the bare hand (Covered-2). The results indicates that wearing gloves decreased the grip MVC, and the thicker the gloves, the less the grip MVC, but the wearing style did not change the MVC (Cotton-2 MVC was indifferent from Covered-2 MVC). As to muscular fatigue, on the other hand, wearing gloves did not affect DeltaMVC, MET, TMVC, or DeltaTMVC. Due to the greater bare-hand MVC and indifferent MET, bare-hand TFG was better than those conditions with gloves. Finally, the load specified here did not alter TMVC or DeltaTMVC, but the greater the load, the more strength degeneration (DeltaMVC) was induced.

Adult↗
PubMed2006

Precision grip function after hand replantation and digital nerve injury.

Understanding how the loss of digital sensibility affects manual dexterity could have important implications for rehabilitation after hand injury. We investigated precision grip function during lifting tasks in seven patients after hand replantation, in five after single digital nerve injury and in four volunteers subjected to digital anaesthesia. Using their affected hand, all participants could successfully lift test objects with parallel and vertical grip surfaces and they all reliably increased the grip force with increasing object weight (0.11-0.55 kg). However, the grip forces used were frequently significantly higher than those applied by the unaffected hand. This was partly due to participants compensating for loss of sensibility with high grip force safety margins against slips, and partly related to misalignments of the fingertips on the grasp surfaces. The latter was most prominent after hand replantation. In a second series of lifting experiments we changed the shape of the grip surfaces in order to investigate the participants' ability to adapt grip forces based on tactile recognition of object shape. An important finding from this series was that in patients with poor clinical outcomes, the contralateral unaffected hand tended to mirror the abnormal grasp patterns of the injured hand. This suggests that control strategies developed for the impaired hand can influence the control of the contralateral uninjured hand.

Adaptation, Physiological↗