Thumb Finger Research Articles

POST-TRAUMATIC COMBINED FLEXION OF THE THUMB, INDEX AND MIDDLE FINGER AFTER INTRINSIC MUSCLES RECONSTRUCTION OF THE HAND: A CASE REPORT

We report a case in which simultaneous flexion of the thumb, index and middle finger occurred 6 months after the surgical reconstruction of the adductor (AM) and first dorsal interosseous (IO) muscles. An anomalous connection in the form of tendon slip associated to fibrous adhesions between the flexor pollicis longus (FPL) tendon, flexor digitorum profundus indicis (FDPI) and middle finger (FDPM) tendons were found. Either ultrasound (US) examination or magnetic resonance imaging (MRI) were unable to detect the site of adhesion. Excision of the slip and radical tenosynoviectomy led to early functional recovery.

Neurologic Soft Signs in Behcet Disease

Patients with Behcet disease have an excess of minor neurologic abnormalities (neurologic soft signs). (a) To investigate the neurologic soft signs (NSS) in Behcet disease (BD) patients who had no neurologic symptoms, by using the neurologic evaluation scale (NES). (b) To evaluate the effect of silent infarction on NES scores in BD patients. Thirty six BD patients without neurologic symptoms and 36 healthy controls were included in the study. NSS were assessed with the NES. Cranial magnetic resonance imaging was conducted to determine the presence of silent cerebral infarcts. Patients with BD had significantly higher scores overall and on each subscale (except for subscale "others") of the NES than the control group's. Tandem walk, adventitious overflow, tremor, graphesthesia, fist edge palm test, Ozeretski test, finger thumb opposition, mirror movements, extinction, synkinesis, convergence, finger nose test, glabellar reflex, grasp reflex, and suck reflex were also significantly higher in patients with BD than in the healthy control group. There were no significant differences in the total NES scores, total subscale scores and each of the NES items between BD patients with silent infarction and those without infarction. Early diagnosis of neurologic involvement in BD is important and the NES is a useful instrument for detecting subclinical neurologic involvement in BD patients.

Design and control of a coupling mechanism-based prosthetic hand

A five-fingered, multi-sensory and biomimetic hand is presented. The cambered palm is specially designed by utilizing the knowledge of anatomy. The position of each finger is arranged according to human hand skeleton. Each finger with three phalanges could fulfill flexion-extension movement independently. All the fingers are designed using coupling link mechanism. The location of the thumb is designed by maximizing interaction area between the thumb and other fingers. The opposite thumb could grasp along a cone surface, while maintaining its function. The hardware architecture is divided into control system and human-machine interaction system. The mechanical parts, sensors and motion control systems are integrated in the hand structure. In addition, a skin-like glove is designed, which makes the hand more humanlike. According to our primary experimental results, the hand can accomplish several grasp modes by applying an intuitive surface electromyography control scheme. The success rate of 10 modes is up to 90%.

A preliminary study on the classification of mutilated injuries of the radial side of the hand

Objective To investigate the classification of mutilated injuries of the radial side of the hand and the clinical outcomes of primary repair. Method A retrospective study of 129 cases of mutilated injuries of the radial side of the hand was carried out. The injuries were divided into five types. In type Ⅰ the mutilated injury only involved the thumb (54 cases). In type Ⅱ the mutilated thumb was accompanied by skin defect of the first web space (33 cases). In type Ⅲ both the thumb and index finger were mutilated along with skin defect of the first web space ( 10 cases). Type Ⅳ involved mutilated injuries of the thumb, index finger and long finger,and skin defect of the first web space (29 cases). In Type Ⅴ the mutilated injuries involved the thumb, index finger, long finger and the radial side of the palm, along with skin defect of the first web space (3 cases).According to the different injury types, various reconstruction strategies were used including toe-to-thumb transfer or heterotopic replantation of the remaining finger for thumb reconstruction, anterolateral thigh flap, dorsalis pedis flap or lateral arm flap for resurfacing of the radial side of the hand. Results Out of the total 129 cases, the transferred flaps and toes or heterotopically replanted fingers in 128 cases survived. The overall survival rate was 99.2%. The patients were follow-up for 1 to 4 years. According to the provisional functional assessment criteria for upper limb issued by the Hand Surgery Society of Chinese Medical Association, the functional recovery was rated as excellent in 46 cases, good in 61 cases, acceptable in 19 cases, and poor in 3 cases. The overall excellent and good rate was 82.9%. Conclusion Classification of mutilated injuries of the radial side of the hand is useful for the selection of proper operative procedures. The clinical outcome is satisfactory after functional reconstruction with primary repair. Key words: Hand; Wounds and injuries; Reconstructive surgical procedures; Typing

Corticospinal Influences on the Distal Muscles of the Hand in Conditions of Inertial Loading

Electromyographic activity and synchronous discharges in the muscles of the wrist induced by transcranial magnetic stimulation of the motor cortex as the thumb and index finger were used to hold a handle bearing a weight were studied during performance of a number of motor tasks. When the subject increased grip force, for example, in response to increases in the weight of the attached load or by voluntarily squeezing the handle, the evoked response increased proportionally to muscle activity. If the subject moved the hand holding the handle up and down with an amplitude of 10 cm and a frequency of 0.5-1 Hz, grip force changed in accordance with the predicted inertial loading. The muscle response in the adductor pollicis muscle increased to a greater extent than the activity in the muscle. The response to sudden inertial loading consisted of a reflex increase in grip force, the muscle response increasing to a lesser extent than activity in the muscle. This suggests that larger increases in evoked muscle responses on up and down movement of the hand with a load are associated with anticipatory changes in grip force. These results are assessed from the point of view of the involvement of the motor cortex in generating anticipatory changes in muscle activity in the distal muscles.

The value of Presurgical Ultrasonography in Chronic Median Nerve Injury of the Palm: Case Report and Review of the Literature

Background: The prevalent approach for localizing and assessing the severity of traumatic peripheral nerve injuries involves clinical evaluation and electrodiagnostic studies. Ultrasonographic examination of the median nerve in patients with carpal tunnel syndrome (CTS) has been proposed as a useful alternative to electromyography (EMG) and nerve conduction velocity (NCV) studies in diagnosing CTS. Case presentation: A 22-year-old man developed numbness and cold intolerance over the left thumb, index and middle fingers after a penetrating injury accident to the left palm caused by a broken glass 7 years before. Primary wound closure was done at a private clinic. High-resolution ultrasonography (Philips HDI 5000 SonoCT Germany) with a 7.0-12 MHz broadband linear probe was used to evaluate the condition of the injured median nerve. Results: Ultrasonography showed complete transection of the median nerve, the presence of a neuroma and the gap in the nerve. Preoperatively, the surgical plans, such as neuroma excision and necessity for nerve grafting were explained to the patient and his family. Conclusion: Our results indicate that preoperative high-resolution ultrasonography is informative in the evaluation of chronic peripheral nerve injuries and can show the type of injury. It is also useful in the planning of surgical intervention.

Spontaneous anterior interosseous nerve palsy with Churg–Strauss syndrome

A 74-year-old woman diagnosed with Churg-Strauss syndrome (CSS) complained of difficulty in flexing her left thumb and index finger. Electromyography demonstrated isolated anterior interosseous nerve (AIN) palsy, with no other peripheral neuropathy. We diagnosed this case as spontaneous AIN palsy complicated with CSS, the first case of this kind. Surgical treatment should be considered if no sign of recovery is seen within six months of onset.

Tangential torque tunes touch

Tangential torque tunes touch

Practice makes perfect, but only with the right hand: Sensitivity to perceptual illusions with awkward grasps decreases with practice in the right but not the left hand

It has been proposed that the visual mechanisms that control well-calibrated actions, such as picking up a small object with a precision grip, are neurally distinct from those that mediate our perception of the object. Thus, grip aperture in such situations has been shown to be remarkably insensitive to many size-contrast illusions. But most of us have practiced such movements hundreds, if not thousands of times. What about less familiar and unpracticed movements? Perhaps they would be less likely to be controlled by specialized visuomotor mechanisms and would therefore be more sensitive to size-contrast illusions. To test this idea, we asked right-handed subjects to pick up small objects using either a normal precision grasp (thumb and index finger) or an awkward grasp (thumb and ring finger), in the context of the Ponzo illusion. Even though this size-contrast illusion had no effect on the scaling of the precision grasp, it did have a significant effect on the scaling of the awkward grasp. Nevertheless, after three consecutive days of practice, even the awkward grasp became resistant to the illusion. In a follow-up experiment, we found that awkward grasps with the left hand (in right handers) did not benefit from practice and remained sensitive to the illusion. We conclude that the skilled target-directed movements are controlled by visual mechanisms that are quite distinct from those controlling unskilled movements, and that these specialized visuomotor mechanisms may be lateralized to the left hemisphere.

頸部術後にＣＲＰＳ（Ｃｏｍｐｌｅｘ Ｒｅｇｉｏｎａｌ Ｐａｉｎ Ｓｙｎｄｒｏｍｅ）ｔｙｐｅ Ｉを生じた１例

We report on a case of complex regional pain syndrome (CRPS) type I. A 27-year-old woman underwent lymph node biopsy of the neck to confirm a diagnosis of histiocytic necrotizing lymphadenitis. Four days after the biopsy, she complained of hyperpathia and limited range of motion on the thumb, forefinger and middle finger of the right hand. She was diagnosed as having CRPS with thermography and treated with glucocorticoid, mecobalamin, and nonsteroidal anti-inflammatory drugs (NSAIDs). The symptoms disappeared within a month and no relapse was seen. CRPS is a disorder of the extremities that is characterized by pain, swelling, limited range of motion, vasomotor instability, skin changes, and patchy bone demineralization. It frequently begins after an injury, surgery, or vascular events, e.g., myocardial infarction or stroke. Tonsillectomy and free forearm flap can cause CRPS. Two types of CRPS have been reported: type I corresponds to patients with CRPS without a definable nerve lesion. Type II which was formerly termed causalgia refers to cases with a definable nerve lesion. The pathogenesis of CRPS is still unclear. CRPS might be caused by the formation of an abnormal reflex arc between the sympathetic nervous system and peripheral vascular components after a causative event. The diagnosis of CRPS is difficult, however, symptoms such as characteristic pain including allodynia and hyperpathia, and altered skin temperature are helpful. Autonomic testing such as thermography and bone scintigraphy are also useful. Prevention and early diagnois are important to treat CRPS. Therefore careful examination and a good understanding of CRPS are recommended.

Viewing hand grip enhances observer's grip force in a body-part-specific manner

We examined whether visual information on the dynamic aspect of the actions performed by an individual can influence an observer's action. Sixteen participants cyclically generated an isometric precision grip force with their right thumb and index finger in synchronization with the contraction (in-phase) or relaxation phase of an experimenter's hand, foot, and mouth movements presented in videos. Visual information of the hand action significantly enhanced the observer's grip force, and this enhancement exclusively occurred during the in-phase condition. These results suggest that the effector matching between the observed and the performed actions and the temporal coincidence in the movement phase are the key factors when visual information on the dynamics of the action of an individual influences the observer's action.

Dupuytren’s disease of the radial side of the hand

Dupuytren’s disease with involvement of the radial aspect of the hand is a clinical entity, which affects the thumb, the first web space, and the index finger. It can be primary or secondary. The palmar fascia anatomy and the clinical aspects of radial Dupuytren’s disease are described. The authors propose a new classification, which has the advantage in requiring only a clinical evaluation. One hundred and fifteen patients were examined for Dupuytren’s disease with radial involvement, primary or secondary, in the Hand Surgery Unit of the University of Modena between 1985 and 1994. Eighty-two (68.3%) of them were treated surgically as hand function was compromised by first web retraction. The most commonly used incisions of the first commissure are straight-line with Z-plasties or the Hirschowitz incision; either a zigzag incision or a Bruner incision is made over the thumb or index finger; Z-plasties described by Iselin are reserved for patients with severe contraction of the index finger. Results were assessed by improvement coefficient, calculated as the ratio of the difference between preoperative and postoperative scores to postoperative scores. Generally, Dupuytren’s disease with radial prevalence is not aggressive and progresses slowly and may be exclusively radial or associated with ulnar disease. In other patients, as the disease progresses, loss of function becomes apparent owing to retraction in adduction of the first commissure and flexion contracture of the thumb or index finger.

Evaluation of a two cursor control device for development of a powered laparoscopic surgical tool

The current study was performed to test two electronic cursor control devices (a Touchpad and a MicroJoystick) for use in an articulating powered laparoscopic tool. A simple target acquisition test was conducted to test how well the cursor control devices could be manipulated and how accurate they were (including endpoint and movement path). The study varied the width (0.27, 0.54 and 1.07 cm) of the target as well as the hand position used (thumb and index finger control). Additionally, each participant was able to choose their ideal operating cursor speed for each cursor control device. The MicroJoystick had a higher throughput and movement variability than the Touchpad. In all other categories tested, the cursor control devices did not differ significantly. The speed of the cursor control devices did not affect the performance of the devices; therefore, the ideal cursor speed could be chosen by the participant. Finally, the hand position did not affect the performance of the devices. This experiment found both hand positions, cursor control devices and all speeds could be used to effectively manipulate an articulating end-effector in a powered, cauterising, laparoscopic tool. This article addresses the advantages and limitations of two control mechanisms for laparoscopic tool controls considering both the subjective and objective data. The controls are tested in two hand positions to test how well the participants can manipulate the device while minimising perceived fatigue.

Motor Imagery After Subcortical Stroke

In recovered subcortical stroke, the pattern of motor network activation during motor execution can appear normal or not, depending on the task. Whether this applies to other aspects of motor function is unknown. We used functional MRI to assess motor imagery (MI), a promising new approach to improve motor function after stroke, and contrasted it to motor execution. Twenty well-recovered patients with hemiparetic subcortical stroke (14 males; mean age, 66.5 years) and 17 aged-matched control subjects were studied. Extensive behavioral screening excluded 8 patients and 4 control subjects due to impaired MI abilities. Subjects performed MI and motor execution of a paced finger-thumb opposition sequence using a functional MRI paradigm that monitored compliance. Activation within the primary motor cortex (BA4a and 4p), dorsal premotor, and supplementary motor areas was examined. The pattern of activation during affected-hand motor execution was not different from control subjects. Affected-hand MI activation was also largely similar to control subjects, including involvement of BA4, but with important differences: (1) unlike control subjects and the nonaffected hand, activation in BA4a and dorsal premotor was not lower during MI as compared with motor execution; (2) the hemispheric balance of BA4p activation was significantly less lateralized than control subjects; and (3) ipsilesional BA4p activation positively correlated with motor performance. In well-recovered subcortical stroke, the motor system, including ipsilesional BA4, is activated during MI despite the lesion. It, however, remains disorganized in proportion to residual motor impairment. Thus, components of movement upstream from execution appear differentially affected after stroke and could be targeted by rehabilitation in more severely affected patients.

Ressecção ampla e transposição fibular no tratamento do TCG da extremidade distal do rádio

OBJETIVO: Avaliação funcional e oncológica do tratamento do TCG do segmento distal do rádio (estadio B3) mediante ressecção ampla e reconstrução com enxerto autólogo avascular da extremidade proximal da fíbula. MÉTODOS: A função residual foi avaliada mediante escore ISOLS, medida do arco residual global do punho operado, do percentual residual da força de preensão da mão e da preensão entre o polegar e o indicador. O controle oncológico foi avaliado mediante exame clínico do membro operado e avaliação por imagens do punho e do tórax. RESULTADOS: 17 pacientes avaliados, dez do sexo feminino (58,8%) e sete do sexo masculino (41,2%) com idades entre 16 e 61 anos (média de 32,3 anos), todos destros. Na avaliação funcional (ISOLS) observamos 11 resultados excelentes, dois bons e um ruim; os três casos que demandaram artrodese evoluíram com escore excelente. O arco residual global foi de 196,2 ± 116,6º. O arco residual do punho operada correspondeu a 58,9% do controle. A força de preensão da mão correspondeu a 55,4 ± 17,4% do controle. O percentual de "pinça" foi de 80,6 ± 14,8% do controle. Não constatamos recidiva ou metástases nesta casuística. CONCLUSÃO: A técnica propiciou resultados funcionais alentadores, assegurando o retorno dos pacientes às suas atividades. A ausência de recidiva local e/ou metástases, observada inclusive nos pacientes com seguimento mais longo, permite sugerir que a técnica parece ser segura no controle oncológico do tumor.

Execution-dependent modulation of corticospinal excitability during action observation

Excitability of the corticospinal pathway increased during observation of an action. The present study investigated whether corticospinal excitability during an action observation is modulated by physical movement executed by the observers themselves. Participants alternately repeated the observation of a pinching action with the thumb and index finger and execution (30 times) of the same action. Motor-evoked potentials (MEPs) induced by transcranial magnetic stimulation were recorded from the first dorsal interosseous muscle during observation of the action. MEP amplitude gradually increased with the number of executions of the same action. However, MEP amplitude did not change when the participants only repeated observation of the pinching action or when the participants alternately repeated observation of the pinching action and execution of the isometric abduction of the index finger. These findings suggest that enhancement of cotricospinal excitability is dependent on the execution of a particular action that is very similar to the observed action.

Advanced Virtual Manipulation based on Modular Haptic Devices

This paper describes a multi-finger haptic interface called MasterFinger which is being developed by the Universidad Politécnica de Madrid, Spain. An index and thumb finger prototype has already been implemented. Details about this device and how it is integrated into haptic scenarios are hereby explained. The paper includes mechanical and control description of the device, as well as some examples of the developed scenarios.

Relationship between chewing side preference and handedness and lateral asymmetry of peripheral factors

Objective To determine whether chewing side preference is related to handedness and lateral asymmetry of occlusal characteristics, muscular force and temporomandibular disorders (TMD) in a dentate population. Design One hundred and seventeen dentate adults participated in this cross-sectional study. Static and dynamic occlusal characteristics were determined at the maximal intercuspal position and at the lateral excursions by scanning interocclusal records and analysing them using image software. Unilateral maximum bite force and finger–thumb grip force were measured by means of a gnathodynamometer. TMD were assessed according to the Research Diagnostic Criteria for TMD. Chewing side preference and masticatory laterality were determined by observing the jaw's movement while each subject chewed silicone. Asymmetry or side difference of the variables was calculated. Correlation between side difference variables and masticatory laterality was studied using Spearman correlation coefficient. Results Fifty-nine subjects chewed on the right, 15 on the left and 43 chewed on both sides. There was no relationship between preferred chewing side and handedness, lateral asymmetry of TMD or side difference in finger–thumb grip force. Significant and positive correlations were observed between masticatory laterality and side differences in bite force and side differences in occlusal contact area at intercuspal position ( P < 0.01). Conclusions Chewing side preference in a dentate population is related to lateral asymmetry of bite force and asymmetry of occlusal contact area at the intercuspal position but not to handedness.

Functional workspace for precision manipulation between thumb and fingers in normal hands

Prehensile functions of hand are based on thumb–finger relationships which are regarded as an essential element in various manipulations of our daily living activities. Although the maximal workspace provides clinicians a way to comprehend the ranges of digital movements, little is known about the “functional workspace” based on thumb–finger relationships. This study defines the functional workspace of the precision thumb–finger grasp as the range of all possible positions in which thumb-tip and each fingertip can simultaneously contact each other. We present a quantitative method for measuring the functional workspace of the human hand. The maximal motion trajectories of thumb-tip and fingertips of twenty subjects were recorded using a video-capture system. The functional workspace of the precision manipulation was calculated via numerical methods based on the maximal workspaces obtained of the thumb-tip and fingertip motions. The ratios of the functional workspace with respect to the maximal workspace of the index, middle, ring and little fingers were calculated as 33.7%, 27.1%, 23.5% and 19.1%, respectively. Although the present approach is still a descriptive work which might require more validations or evidences to justify, the results obtained may become normal standards for practical use in objective handicapped authentications, insurance claims, and rehabilitation programs as well as criteria for ergonomic design considerations in the near future.

Why Hands Matter

This paper illustrates various aspects of technological advancements in designs and functioning of prosthetic hands. Schunk, a top supplier of robotic grippers, believes humanoid hands will make robots more flexible and eliminate tens of thousands of dollars’ worth of auxiliary equipment. Shadow Robot's hand can grip an egg or a pair of pliers. The company is building hands that mimic human motion for service robots, which will act like valets to perform a variety of tasks for their masters. With a hand, a robot could determine if it could get to a part and then configure its hand to get to the location and grasp the part. Touch Bionics’s i-LIMB hand combines an independently powered thumb and index finger with three fingers that move in unison. Muscle contractions in the forearm control its movement. It can peel a banana, lifting a credit card off a table, or holding a briefcase. It is expected that surgeons in hospitals may use robotic humanoid hands to perform delicate operations in remote locations.