Bioinspired Robotic Fingers Based on Pneumatic Actuator and 3D Printing of Smart Material.

PubMed

Yang, Yang; Chen, Yonghua; Li, Yingtian; Chen, Michael Z Q; Wei, Ying

2017-06-01

In this article, we have proposed a novel robotic finger design principle aimed to address two challenges in soft pneumatic grippers-the controllability of the stiffness and the controllability of the bending position. The proposed finger design is composed of a 3D printed multimaterial substrate and a soft pneumatic actuator. The substrate has four polylactic acid (PLA) segments interlocked with three shape memory polymer (SMP) joints, inspired by bones and joints in human fingers. By controlling the thermal energy of an SMP joint, the stiffness of the joints is modulated due to the dramatic change in SMP elastic modulus around its glass transition temperature (T g ). When SMP joints are heated above T g , they exhibit very small stiffness, allowing the finger to easily bend around the SMP joints if the attached soft actuator is actuated. When there is no force from the soft actuator, shape recovery stress in SMP contributes to the finger's shape restoration. Since each joint's rotation can be individually controlled, the position control of the finger is made possible. Experimental analysis has been conducted to show the finger's variable stiffness and the result is compared with the analytical values. It is found that the stiffness ratio can be 24.9 times for a joint at room temperature (20°C) and at an elevated temperature of 60°C when air pressure p of the soft actuator is turned off. Finally, a gripper composed of two fingers is fabricated for demonstration.

Prevalence of sesamoid bones in the interphalangeal joint of the thumb and fingers: a radiographic study.

PubMed

Seki, Yasuhiro; Hoshino, Yuko; Kuroda, Hiroshi

2013-10-01

The prevalence of sesamoid bones in the hands has been reported in some previous articles. Most of them, however, have reported sesamoid bones of the metacarpophalangeal joint of the hand and of the interphalangeal (IP) joint of the thumb. The present study investigates the prevalence of sesamoid bones of the IP joint of the thumb and fingers. A retrospective review of radiologic views of the IP joints in the thumb or fingers was performed, including a total of 650 patients (1,096 thumbs or fingers). Sesamoid bones were found in the IP joint of the thumb at 67% (212 of 318), while the index, middle, ring, little fingers had sesamoid bones in the proximal interphlangeal (PIP) joint at 0% (0 of 172), 0.4% (1 of 244), 0.5% (1 of 183), and 1% (2 of 179), respectively. None of the four fingers had sesamoid bones in the distal IP joint. Previous articles have described the similar prevalence to the present study, of sesamoid bones of the IP joint of the thumb, while some others reported the different prevalence. About the PIP joint, no previous articles have found a sesamoid bone. Because the lateral X-ray view is more accurate and suitable to evaluate sesamoid bones, we used the lateral one for the present study. The knowledge that sesamoid bones occurs at these rates in the thumb IP joint and finger PIP joints is helpful to differentiate chip fractures from sesamoid bones near the IP joint, including the PIP joint. Copyright © 2012 Wiley Periodicals, Inc.

Cancer risk among patients with finger and hand joint and temporo-mandibular joint prostheses in Denmark.

PubMed

Fryzek, J P; Mellemkjaer, L; McLaughlin, J K; Blot, W J; Olsen, J H

1999-05-31

The use of artificial joint implants has risen greatly over the past years. However, few investigations of the cancer risk associated with implants have been performed. We investigated cancer risk in patients with finger and hand joint and temporo-mandibular (TMJ) joint implants. A nationwide cohort in Denmark of patients with finger and hand joint prostheses (n = 858) or TMJ implants (n = 389) was followed from January 1, 1977, to December 31, 1995, to evaluate any potential cancer risks subsequent to receiving these implants. Standardized incidence ratios (SIRs) for all cancers were 1.0 (95% CI = 0.8-1.2) for the finger and hand joint cohort and 1.1 (95% CI = 0.8-1.7) for the TMJ cohort. A significant risk for non-Hodgkin's lymphoma was found in the finger and hand joint cohort (SIR = 3.8, 95% CI = 1.5-7.8). When the finger and hand joint cohort was stratified by diagnosis of rheumatoid arthritis, the excess risk was seen only in the group with rheumatoid arthritis. This is consistent with past studies, which have found an association between rheumatoid arthritis and non-Hodgkin's lymphoma. Our results provide evidence that the cancer risk for patients with finger and hand joint prostheses and TMJ implants is similar to that for the general population.

Hand kinematics of piano playing

PubMed Central

Flanders, Martha; Soechting, John F.

2011-01-01

Dexterous use of the hand represents a sophisticated sensorimotor function. In behaviors such as playing the piano, it can involve strong temporal and spatial constraints. The purpose of this study was to determine fundamental patterns of covariation of motion across joints and digits of the human hand. Joint motion was recorded while 5 expert pianists played 30 excerpts from musical pieces, which featured ∼50 different tone sequences and fingering. Principal component analysis and cluster analysis using an expectation-maximization algorithm revealed that joint velocities could be categorized into several patterns, which help to simplify the description of the movements of the multiple degrees of freedom of the hand. For the thumb keystroke, two distinct patterns of joint movement covariation emerged and they depended on the spatiotemporal patterns of the task. For example, the thumb-under maneuver was clearly separated into two clusters based on the direction of hand translation along the keyboard. While the pattern of the thumb joint velocities differed between these clusters, the motions at the metacarpo-phalangeal and proximal-phalangeal joints of the four fingers were more consistent. For a keystroke executed with one of the fingers, there were three distinct patterns of joint rotations, across which motion at the striking finger was fairly consistent, but motion of the other fingers was more variable. Furthermore, the amount of movement spillover of the striking finger to the adjacent fingers was small irrespective of the finger used for the keystroke. These findings describe an unparalleled amount of independent motion of the fingers. PMID:21880938

Modeling the finger joint moments in a hand at the maximal isometric grip: the effects of friction.

PubMed

Wu, John Z; Dong, Ren G; McDowell, Thomas W; Welcome, Daniel E

2009-12-01

The interaction between the handle and operator's hand affects the comfort and safety of tool and machine operations. In most of the previous studies, the investigators considered only the normal contact forces. The effect of friction on the joint moments in fingers has not been analyzed. Furthermore, the observed contact forces have not been linked to the internal musculoskeletal loading in the previous experimental studies. In the current study, we proposed a universal model of a hand to evaluate the joint moments in the fingers during grasping tasks. The hand model was developed on the platform of the commercial software package AnyBody. Only four fingers (index, long, ring, and little finger) were included in the model. The anatomical structure of each finger is comprised of four phalanges (distal, middle, proximal, and metacarpal phalange). The simulations were performed using an inverse dynamics technique. The joint angles and the normal contact forces on each finger section reported by previous researchers were used as inputs, while the joint moments of each finger were predicted. The predicted trends of the dependence of the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joint moments on the cylinder diameter agree with those of the contact forces on the fingers observed in the previous experimental study. Our results show that the DIP and PIP joint moments reach their maximums at a cylinder diameter of about 31mm, which is consistent with the trend of the finger contact forces measured in the experiments. The proposed approach will be useful for simulating musculoskeletal loading in the hand for occupational activities, thereby optimizing tool-handle design.

21 CFR 888.3210 - Finger joint metal/metal constrained cemented prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Finger joint metal/metal constrained cemented prosthesis. 888.3210 Section 888.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3210 Finger joint...

21 CFR 888.3210 - Finger joint metal/metal constrained cemented prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Finger joint metal/metal constrained cemented prosthesis. 888.3210 Section 888.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3210 Finger joint...

21 CFR 888.3200 - Finger joint metal/metal constrained uncemented prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Finger joint metal/metal constrained uncemented prosthesis. 888.3200 Section 888.3200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3200 Finger joint...

21 CFR 888.3210 - Finger joint metal/metal constrained cemented prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Finger joint metal/metal constrained cemented prosthesis. 888.3210 Section 888.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3210 Finger joint...

21 CFR 888.3200 - Finger joint metal/metal constrained uncemented prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Finger joint metal/metal constrained uncemented prosthesis. 888.3200 Section 888.3200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3200 Finger joint...

21 CFR 888.3200 - Finger joint metal/metal constrained uncemented prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Finger joint metal/metal constrained uncemented prosthesis. 888.3200 Section 888.3200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3200 Finger joint...

Involuntary Neuromuscular Coupling between the Thumb and Finger of Stroke Survivors during Dynamic Movement.

PubMed

Jones, Christopher L; Kamper, Derek G

2018-01-01

Finger-thumb coordination is crucial to manual dexterity but remains incompletely understood, particularly following neurological injury such as stroke. While being controlled independently, the index finger and thumb especially must work in concert to perform a variety of tasks requiring lateral or palmar pinch. The impact of stroke on this functionally critical sensorimotor control during dynamic tasks has been largely unexplored. In this study, we explored finger-thumb coupling during close-open pinching motions in stroke survivors with chronic hemiparesis. Two types of perturbations were applied randomly to the index with a novel Cable-Actuated Finger Exoskeleton: a sudden joint acceleration stretching muscle groups of the index finger and a sudden increase in impedance in selected index finger joint(s). Electromyographic signals for specific thumb and index finger muscles, thumb tip trajectory, and index finger joint angles were recorded during each trial. Joint angle perturbations invoked reflex responses in the flexor digitorum superficialis (FDS), first dorsal interossei (FDI), and extensor digitorum communis muscles of the index finger and heteronymous reflex responses in flexor pollicis brevis of the thumb ( p  < 0.017). Phase of movement played a role as a faster peak reflex response was observed in FDI during opening than during closing ( p  < 0.002) and direction of perturbations resulted in shorter reflex times for FDS and FDI ( p  < 0.012) for extension perturbations. Surprisingly, when index finger joint impedance was suddenly increased, thumb tip movement was substantially increased, from 2 to 10 cm ( p  < 0.001). A greater effect was seen during the opening phase ( p  < 0.044). Thus, involuntary finger-thumb coupling was present during dynamic movement, with perturbation of the index finger impacting thumb activity. The degree of coupling modulated with the phase of motion. These findings reveal a potential mechanism for direct intervention to improve poststroke hand mobility and provide insight on prospective neurologically oriented therapies.

Arthrodesis of the thumb interphalangeal joint and finger distal interphalangeal joints with a headless compression screw.

PubMed

Cox, Christopher; Earp, Brandon E; Floyd, W Emerson; Blazar, Philip E

2014-01-01

To study the results of using a small, headless compression screw (AcuTwist) for thumb interphalangeal (IP) joint and finger distal interphalangeal (DIP) joint arthrodeses. Between November 2007 and January 2012, 48 primary arthrodeses of the thumb IP joint or DIP joint in the other digits were performed in 29 consecutive patients with AcuTwist devices. Indications for arthrodesis included 19 cases of osteoarthritis in 25 fingers, 3 cases of lupus in 9 fingers, 2 cases of post-traumatic osteoarthritis in 2 fingers, and 1 case and finger each of acute trauma, neuromuscular disorder, postinfectious osteoarthritis, boutonniere deformity, and Dupuytren contracture. Charts were reviewed for clinical data, and radiographs were assessed for alignment and healing. Age averaged 59 years and follow-up averaged 12 months (range, 2-50 mo). Union occurred in 43 out of 46 fingers (94%). There were no cases of nail deformity, wound complications, tip hypersensitivity, or clinically notable malalignment. Three arthrodeses failed to fuse, including 2 asymptomatic nonunions and 1 fixation loss requiring revision with autograft. The complication rate was 9%. Distal digital joint arthrodesis with the AcuTwist resulted in a fusion rate of 94% with a complication rate of 9%. Our rate of fusion compares favorably with prior series using other methods of fixation. Therapeutic IV. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Change in the temporal coordination of the finger joints with ulnar nerve block during different power grips analyzed with a sensor glove.

PubMed

Wachter, N J; Mentzel, M; Häderer, C; Krischak, G D; Gülke, J

2018-02-01

Ulnar nerve injuries can cause deficient hand movement patterns. Their assessment is important for diagnosis and rehabilitation in hand surgery cases. The purpose of this study was to quantify the changes in temporal coordination of the finger joints during different power grips with an ulnar nerve block by means of a sensor glove. In 21 healthy subjects, the onset and end of the active flexion of the 14 finger joints when gripping objects of different diameters was recorded by a sensor glove. The measurement was repeated after an ulnar nerve block was applied in a standardized setting. The change in the temporal coordination of the metacarpophalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints with and without the nerve block was calculated within the same subject. In healthy subjects, the MCP joints started their movement prior to the PIP joints in the middle and ring finger, whereas this occurred in the reverse order at the index and little finger. The DIP joint onset was significantly delayed (P<0.01). With the ulnar nerve block, this coordination shifted towards simultaneous onset of all joints, independent of the grip diameter. The thumb and index finger were affected the least. With an ulnar nerve block, the PIP joints completed their movement prior to the MCP joints when gripping small objects (G1 and G2), whereas the order was reversed with larger objects (G3 and G4). The alterations with ulnar nerve block affected mainly the little finger when gripping small objects. With larger diameter objects, all fingers had a significant delay at the end of the PIP joint movement relative to the MCP and DIP joints, and the PIP and DIP joint sequence was reversed (P<0.01). Based on the significant changes in temporal coordination of finger flexion during different power grips, there are biomechanical effects of loss of function of the intrinsic muscles caused by an ulnar nerve block on the fine motor skills of the hand. This can be important for the diagnosis and rehabilitation of ulnar nerve lesions of the hand. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

Temporal Control and Hand Movement Efficiency in Skilled Music Performance

PubMed Central

Goebl, Werner; Palmer, Caroline

2013-01-01

Skilled piano performance requires considerable movement control to accomplish the high levels of timing and force precision common among professional musicians, who acquire piano technique over decades of practice. Finger movement efficiency in particular is an important factor when pianists perform at very fast tempi. We document the finger movement kinematics of highly skilled pianists as they performed a five-finger melody at very fast tempi. A three-dimensional motion-capture system tracked the movements of finger joints, the hand, and the forearm of twelve pianists who performed on a digital piano at successively faster tempi (7–16 tones/s) until they decided to stop. Joint angle trajectories computed for all adjacent finger phalanges, the hand, and the forearm (wrist angle) indicated that the metacarpophalangeal joint contributed most to the vertical fingertip motion while the proximal and distal interphalangeal joints moved slightly opposite to the movement goal (finger extension). An efficiency measure of the combined finger joint angles corresponded to the temporal accuracy and precision of the pianists’ performances: Pianists with more efficient keystroke movements showed higher precision in timing and force measures. Keystroke efficiency and individual joint contributions remained stable across tempo conditions. Individual differences among pianists supported the view that keystroke efficiency is required for successful fast performance. PMID:23300946

Modeling of the interaction between grip force and vibration transmissibility of a finger.

PubMed

Wu, John Z; Welcome, Daniel E; McDowell, Thomas W; Xu, Xueyan S; Dong, Ren G

2017-07-01

It is known that the vibration characteristics of the fingers and hand and the level of grip action interacts when operating a power tool. In the current study, we developed a hybrid finger model to simulate the vibrations of the hand-finger system when gripping a vibrating handle covered with soft materials. The hybrid finger model combines the characteristics of conventional finite element (FE) models, multi-body musculoskeletal models, and lumped mass models. The distal, middle, and proximal finger segments were constructed using FE models, the finger segments were connected via three flexible joint linkages (i.e., distal interphalangeal joint (DIP), proximal interphalangeal joint (PIP), and metacarpophalangeal (MCP) joint), and the MCP joint was connected to the ground and handle via lumped parameter elements. The effects of the active muscle forces were accounted for via the joint moments. The bone, nail, and hard connective tissues were assumed to be linearly elastic whereas the soft tissues, which include the skin and subcutaneous tissues, were considered as hyperelastic and viscoelastic. The general trends of the model predictions agree well with the previous experimental measurements in that the resonant frequency increased from proximal to the middle and to the distal finger segments for the same grip force, that the resonant frequency tends to increase with increasing grip force for the same finger segment, especially for the distal segment, and that the magnitude of vibration transmissibility tends to increase with increasing grip force, especially for the proximal segment. The advantage of the proposed model over the traditional vibration models is that it can predict the local vibration behavior of the finger to a tissue level, while taking into account the effects of the active musculoskeletal force, the effects of the contact conditions on vibrations, the global vibration characteristics. Published by Elsevier Ltd.

Finger jointing green southern yellow pine with a soy-based adhesive

Treesearch

Philip H. Steele; Roland E. Kreibicha; Petrus J. Steynberg; Richard W. Hemingway

1998-01-01

The authors present results of laboratory tests for a soy-based adhesive to bond southern yellow pine using the finger-jointing method. There was some reason to suspect that finger jointing of southern yellow pine (SYP) with the honeymoon system using soy-based adhesive might prove more difficult than for western species. The Wood Handbook classes western species in...

Comparison of dominant hand range of motion among throwing types in baseball pitchers.

PubMed

Wang, Lin-Hwa; Kuo, Li-Chieh; Shih, Sheng-Wen; Lo, Kuo-Cheng; Su, Fong-Chin

2013-08-01

Previous research on baseball pitchers' wrists, elbows, and should joints contributes to our understanding of pitchers' control over delicate joint motion and ball release. However, limited research on forearm, wrist, and hand joints prevents full comprehension of the throwing mechanism. The present descriptive laboratory study quantifies angular performances of hand and wrist joints while pitching breaking balls, including fastballs, curveballs and sliders, among pitchers with different skill levels. Nineteen baseball pitchers performed required pitching tasks (10 from university and 9 from high school). A three-dimensional motion analysis system collected pitching motion data. The range of joint motion in the wrist and proximal interphalangeal (PIP) and metacarpophalangeal (MP) joints of the index and middle fingers were compared among fastballs, curveballs and sliders. Thirteen reflective markers were placed on selected anatomic landmarks of the wrist, middle and index fingers of the hand. Wrist flexion angle in the pitching acceleration phase was larger in fastballs (20.58±4.07°) and sliders (22.48±5.45°) than in curveballs (9.08±3.03°) (p = .001). The flexion angle of the PIP joint was significantly larger in curveballs (38.5±3.8°) than in fastballs (30.3±4.8°) and sliders (30.2±4.5°) (p=.004) of the middle finger. Abduction angle of MP joint on the middle finger was significantly larger in curveballs (15.4 ±3.6°) than in fastballs (8.9±1.2°) and sliders (6.9±2.9°) (p=.001) of the middle finger, and the abduction angle of index finger was significantly larger in sliders (13.5±15.0°) than in fastballs (7.2 ±2.8°) (p=.007). Hand and wrist motion and grip types affect the relative position between fingers and ball, which produces different types of baseball pitches. A larger extension angle of the wrist joint and the coordination of middle and index fingers are crucial when pitching a fastball. Abduction and flexion movement on the MP joint of the middle finger are important for a curveball. MP joint abduction and flexion movement of the index finger produce sliders. Understanding the control mechanism in a throwing hand can help improve training protocols in either injury prevention or performance improvement for baseball pitchers. Copyright © 2013 Elsevier B.V. All rights reserved.

Management of the Stiff Finger: Evidence and Outcomes

PubMed Central

Yang, Guang; McGlinn, Evan P.; Chung, Kevin C.

2014-01-01

SYNOPSIS The term “stiff finger” refers to a reduction in the range of motion in the finger, and it is a condition that has many different causes and involves a number of different structures. Almost all injuries of the fingers and some diseases can cause finger stiffness. Hand surgeons often face difficulty treating stiff fingers that are affected by irreversible soft tissues fibrosis. Stiff fingers can be divided into flexion and extension deformities. They can also be sub-classified into four categories according to the involved tissues extending from the skin to the joint capsule. Prevention of stiff fingers by judicious mobilization of the joints is prudent to avoid more complicated treatment after established stiffness occurs. Static progressive and dynamic splints have been considered as effective non-operative interventions to treat stiff fingers. Most authors believe force of joint distraction and time duration of stretching are two important factors to consider while applying a splint or cast. We also introduce the concepts of capsulotomy and collateral ligament release and other soft tissue release of the MCP and PIP joint in this article. Future outcomes research is vital to assessing the effectiveness of these surgical procedures and guiding postoperative treatment recommendations. PMID:24996467

Extrinsic versus intrinsic hand muscle dominance in finger flexion.

PubMed

Al-Sukaini, A; Singh, H P; Dias, J J

2016-05-01

This study aims to identify the patterns of dominance of extrinsic or intrinsic muscles in finger flexion during initiation of finger curl and mid-finger flexion. We recorded 82 hands of healthy individuals (18-74 years) while flexing their fingers and tracked the finger joint angles of the little finger using video motion tracking. A total of 57 hands (69.5%) were classified as extrinsic dominant, where the finger flexion was initiated and maintained at proximal interphalangeal and distal interphalangeal joints. A total of 25 (30.5%) were classified as intrinsic dominant, where the finger flexion was initiated and maintained at the metacarpophalangeal joint. The distribution of age, sex, dominance, handedness and body mass index was similar in the two groups. This knowledge may allow clinicians to develop more efficient rehabilitation regimes, since intrinsic dominant individuals would not initiate extrinsic muscle contraction till later in finger flexion, and might therefore be allowed limited early active motion. For extrinsic dominant individuals, by contrast, initial contraction of extrinsic muscles would place increased stress on the tendon repair site if early motion were permitted. © The Author(s) 2016.

Design of a Reconfigurable Robotic System for Flexoextension Fitted to Hand Fingers Size

PubMed Central

Castillo-Castaneda, Eduardo

2016-01-01

Due to the growing demand for assistance in rehabilitation therapies for hand movements, a robotic system is proposed to mobilize the hand fingers in flexion and extension exercises. The robotic system is composed by four, type slider-crank, mechanisms that have the ability to fit the user fingers length from the index to the little finger, through the adjustment of only one link for each mechanism. The trajectory developed by each mechanism corresponds to the natural flexoextension path of each finger. The amplitude of the rotations for metacarpophalangeal joint (MCP) and proximal interphalangeal joint (PIP) varies from 0 to 90° and the distal interphalangeal joint (DIP) varies from 0 to 60°; the joint rotations are coordinated naturally. The four R-RRT mechanisms orientation allows a 15° abduction movement for index, ring, and little fingers. The kinematic analysis of this mechanism was developed in order to assure that the displacement speed and smooth acceleration into the desired range of motion and the simulation results are presented. The reconfiguration of mechanisms covers about 95% of hand sizes of a group of Mexican adult population. Maximum trajectory tracking error is less than 3% in full range of movement and it can be compensated by the additional rotation of finger joints without injury to the user. PMID:27524880

Design of a Reconfigurable Robotic System for Flexoextension Fitted to Hand Fingers Size.

PubMed

Aguilar-Pereyra, J Felipe; Castillo-Castaneda, Eduardo

2016-01-01

Due to the growing demand for assistance in rehabilitation therapies for hand movements, a robotic system is proposed to mobilize the hand fingers in flexion and extension exercises. The robotic system is composed by four, type slider-crank, mechanisms that have the ability to fit the user fingers length from the index to the little finger, through the adjustment of only one link for each mechanism. The trajectory developed by each mechanism corresponds to the natural flexoextension path of each finger. The amplitude of the rotations for metacarpophalangeal joint (MCP) and proximal interphalangeal joint (PIP) varies from 0 to 90° and the distal interphalangeal joint (DIP) varies from 0 to 60°; the joint rotations are coordinated naturally. The four R-RRT mechanisms orientation allows a 15° abduction movement for index, ring, and little fingers. The kinematic analysis of this mechanism was developed in order to assure that the displacement speed and smooth acceleration into the desired range of motion and the simulation results are presented. The reconfiguration of mechanisms covers about 95% of hand sizes of a group of Mexican adult population. Maximum trajectory tracking error is less than 3% in full range of movement and it can be compensated by the additional rotation of finger joints without injury to the user.

Ability of finger-jointed lumber to maintain load at elevated temperatures

Treesearch

Douglas R. Rammer; Samuel L. Zelinka; Laura E Hasburgh; Steven T. Craft

2018-01-01

This article presents a test method that was developed to screen adhesive formulations for finger-jointed lumber. The goal was to develop a small-scale test that could be used to predict whether an adhesive would pass a full-scale ASTM E119 wall assembly test. The method involved loading a 38-mm square finger-jointed sample in a four-point bending test inside of an...

Finger-Jointed Wood Products.

DTIC Science & Technology

1981-04-01

these melamines do not have the same Urea resins are generally marketed adhesives does not always develop resistance to weathering as do in liquid form...OF durable, colorless glueline is required. been developed for use in RF curing. FINGER JOINTS MelamineUrea Resins IN STRUCTURAL Melamine - urea resins ...finger duced either by dry blending urea and moplastic, softening if temperature is joints, strength is expressed as a melamine resins or by blending

Involuntary Neuromuscular Coupling between the Thumb and Finger of Stroke Survivors during Dynamic Movement

PubMed Central

Jones, Christopher L.; Kamper, Derek G.

2018-01-01

Finger–thumb coordination is crucial to manual dexterity but remains incompletely understood, particularly following neurological injury such as stroke. While being controlled independently, the index finger and thumb especially must work in concert to perform a variety of tasks requiring lateral or palmar pinch. The impact of stroke on this functionally critical sensorimotor control during dynamic tasks has been largely unexplored. In this study, we explored finger–thumb coupling during close–open pinching motions in stroke survivors with chronic hemiparesis. Two types of perturbations were applied randomly to the index with a novel Cable-Actuated Finger Exoskeleton: a sudden joint acceleration stretching muscle groups of the index finger and a sudden increase in impedance in selected index finger joint(s). Electromyographic signals for specific thumb and index finger muscles, thumb tip trajectory, and index finger joint angles were recorded during each trial. Joint angle perturbations invoked reflex responses in the flexor digitorum superficialis (FDS), first dorsal interossei (FDI), and extensor digitorum communis muscles of the index finger and heteronymous reflex responses in flexor pollicis brevis of the thumb (p < 0.017). Phase of movement played a role as a faster peak reflex response was observed in FDI during opening than during closing (p < 0.002) and direction of perturbations resulted in shorter reflex times for FDS and FDI (p < 0.012) for extension perturbations. Surprisingly, when index finger joint impedance was suddenly increased, thumb tip movement was substantially increased, from 2 to 10 cm (p < 0.001). A greater effect was seen during the opening phase (p < 0.044). Thus, involuntary finger–thumb coupling was present during dynamic movement, with perturbation of the index finger impacting thumb activity. The degree of coupling modulated with the phase of motion. These findings reveal a potential mechanism for direct intervention to improve poststroke hand mobility and provide insight on prospective neurologically oriented therapies. PMID:29545767

Multi-fingered robotic hand

NASA Technical Reports Server (NTRS)

Ruoff, Carl F. (Inventor); Salisbury, Kenneth, Jr. (Inventor)

1990-01-01

A robotic hand is presented having a plurality of fingers, each having a plurality of joints pivotally connected one to the other. Actuators are connected at one end to an actuating and control mechanism mounted remotely from the hand and at the other end to the joints of the fingers for manipulating the fingers and passing externally of the robot manipulating arm in between the hand and the actuating and control mechanism. The fingers include pulleys to route the actuators within the fingers. Cable tension sensing structure mounted on a portion of the hand are disclosed, as is covering of the tip of each finger with a resilient and pliable friction enhancing surface.

Coordinated turn-and-reach movements. II. Planning in an external frame of reference

NASA Technical Reports Server (NTRS)

Pigeon, Pascale; Bortolami, Simone B.; DiZio, Paul; Lackner, James R.

2003-01-01

The preceding study demonstrated that normal subjects compensate for the additional interaction torques generated when a reaching movement is made during voluntary trunk rotation. The present paper assesses the influence of trunk rotation on finger trajectories and on interjoint coordination and determines whether simultaneous turn-and-reach movements are most simply described relative to a trunk-based or an external reference frame. Subjects reached to targets requiring different extents of arm joint and trunk rotation at a natural pace and quickly in normal lighting and in total darkness. We first examined whether the larger interaction torques generated during rapid turn-and-reach movements perturb finger trajectories and interjoint coordination and whether visual feedback plays a role in compensating for these torques. These issues were addressed using generalized Procrustes analysis (GPA), which attempts to overlap a group of configurations (e.g., joint trajectories) through translations and rotations in multi-dimensional space. We first used GPA to identify the mean intrinsic patterns of finger and joint trajectories (i.e., their average shape irrespective of location and orientation variability in the external and joint workspaces) from turn-and-reach movements performed in each experimental condition and then calculated their curvatures. We then quantified the discrepancy between each finger or joint trajectory and the intrinsic pattern both after GPA was applied individually to trajectories from a pair of experimental conditions and after GPA was applied to the same trajectories pooled together. For several subjects, joint trajectories but not finger trajectories were more curved in fast than slow movements. The curvature of both joint and finger trajectories of turn-and-reach movements was relatively unaffected by the vision conditions. Pooling across speed conditions significantly increased the discrepancy between joint but not finger trajectories for most subjects, indicating that subjects used different patterns of interjoint coordination in slow and fast movements while nevertheless preserving the shape of their finger trajectory. Higher movement speeds did not disrupt the arm joint rotations despite the larger interaction torques generated. Rather, subjects used the redundant degrees of freedom of the arm/trunk system to achieve similar finger trajectories with differing joint configurations. We examined finger movement patterns and velocity profiles to determine the frame of reference in which turn-and-reach movements could be most simply described. Finger trajectories of turn-and-reach movements had much larger curvatures and their velocity profiles were less smooth and less bell-like in trunk-based coordinates than in external coordinates. Taken together, these results support the conclusion that turn-and-reach movements are controlled in an external frame of reference.

Effects of electromyography-driven robot-aided hand training with neuromuscular electrical stimulation on hand control performance after chronic stroke.

PubMed

Rong, Wei; Tong, Kai Yu; Hu, Xiao Ling; Ho, Sze Kit

2015-03-01

An electromyography-driven robot system integrated with neuromuscular electrical stimulation (NMES) was developed to investigate its effectiveness on post-stroke rehabilitation. The performance of this system in assisting finger flexion/extension with different assistance combinations was evaluated in five stroke subjects. Then, a pilot study with 20-sessions training was conducted to evaluate the training's effectiveness. The results showed that combined assistance from the NMES-robot could improve finger movement accuracy, encourage muscle activation of the finger muscles and suppress excessive muscular activities in the elbow joint. When assistances from both NMES and the robot were 50% of their maximum assistances, finger-tracking performance had the best results, with the lowest root mean square error, greater range of motion, higher voluntary muscle activations of the finger joints and lower muscle co-contraction in the finger and elbow joints. Upper limb function improved after the 20-session training, indicated by the increased clinical scores of Fugl-Meyer Assessment, Action Research Arm Test and Wolf Motor Function Test. Muscle co-contraction was reduced in the finger and elbow joints reflected by the Modified Ashworth Scale. The findings demonstrated that an electromyography-driven NMES-robot used for chronic stroke improved hand function and tracking performance. Further research is warranted to validate the method on a larger scale. Implications for Rehabilitation The hand robotics and neuromuscular electrical stimulation (NMES) techniques are still separate systems in current post-stroke hand rehabilitation. This is the first study to investigate the combined effects of the NMES and robot on hand rehabilitation. The finger tracking performance was improved with the combined assistance from the EMG-driven NMES-robot hand system. The assistance from the robot could improve the finger movement accuracy and the assistance from the NMES could reduce the muscle co-contraction on finger and elbow joints. The upper limb functions were improved on chronic stroke patients after the pilot study of 20-session hand training with the combined assistance from the EMG-driven NMES-robot. The muscle spasticity on finger and elbow joints was reduced after the training.

Imaging osteoarthritis in the knee joints using x-ray guided diffuse optical tomography

NASA Astrophysics Data System (ADS)

Zhang, Qizhi; Yuan, Zhen; Sobel, Eric S.; Jiang, Huabei

2010-02-01

In our previous studies, near-infrared (NIR) diffuse optical tomography (DOT) had been successfully applied to imaging osteoarthritis (OA) in the finger joints where significant difference in optical properties of the joint tissues was evident between healthy and OA finger joints. Here we report for the first time that large joints such as the knee can also be optically imaged especially when DOT is combined with x-ray tomosynthesis where the 3D image of the bones from x-ray is incorporated into the DOT reconstruction as spatial a priori structural information. This study demonstrates that NIR light can image large joints such as the knee in addition to finger joints, which will drastically broaden the clinical utility of our x-ray guided DOT technique for OA diagnosis.

Estimation of continuous multi-DOF finger joint kinematics from surface EMG using a multi-output Gaussian Process.

PubMed

Ngeo, Jimson; Tamei, Tomoya; Shibata, Tomohiro

2014-01-01

Surface electromyographic (EMG) signals have often been used in estimating upper and lower limb dynamics and kinematics for the purpose of controlling robotic devices such as robot prosthesis and finger exoskeletons. However, in estimating multiple and a high number of degrees-of-freedom (DOF) kinematics from EMG, output DOFs are usually estimated independently. In this study, we estimate finger joint kinematics from EMG signals using a multi-output convolved Gaussian Process (Multi-output Full GP) that considers dependencies between outputs. We show that estimation of finger joints from muscle activation inputs can be improved by using a regression model that considers inherent coupling or correlation within the hand and finger joints. We also provide a comparison of estimation performance between different regression methods, such as Artificial Neural Networks (ANN) which is used by many of the related studies. We show that using a multi-output GP gives improved estimation compared to multi-output ANN and even dedicated or independent regression models.

Improving the fatigue resistance of adhesive joints in laminated wood structures

NASA Technical Reports Server (NTRS)

Laufenberg, Theodore L.; River, Bryan H.; Murmanis, Lidija L.; Christiansen, Alfred W.

1988-01-01

The premature fatigue failure of a laminated wood/epoxy test beam containing a cross section finger joint was the subject of a multi-disciplinary investigation. The primary objectives were to identify the failure mechanisms which occurred during the finger joint test and to provide avenues for general improvements in the design and fabrication of adhesive joints in laminated wood structures.

Outcomes of Silicone Arthroplasty Stratified by Fingers for the Rheumatoid Metacarpophalangeal Joints

PubMed Central

Chung, Kevin C.; Kotsis, Sandra V.; Shaw Wilgis, E. F.; Fox, David A.; Regan, Marian; Kim, H. Myra; Burke, Frank D.

2015-01-01

Purpose Previous studies have demonstrated that outcomes for the ulnar digits appear to be worse than the radial digits after silicone metacarpophalangeal joint arthroplasty (SMPA) for the rheumatoid hand. This study examines various components of hand deformities in an effort to understand SMPA outcomes in terms of metacarpophalangeal joint range of motion and alignment. We hypothesize that the ulnar fingers will have less improvement marked by greater ulnar drift, extension lag, and less metacarpophalangeal joint (MCPJ) arc of motion than the radial fingers. Methods 68 surgical patients were recruited from 3 sites in this multi-center international prospective cohort study. All patients had a diagnosis of rheumatoid arthritis, were between the ages of 18–80, and were eligible to undergo SMPA based on measured hand deformities (extensor lag and ulnar drift). Ulnar drift, extension lag, and arc of motion for the MCPJ of each finger were measured at baseline (pre-surgical) and 1-year after SMPA. Results All fingers showed an improvement in ulnar drift from baseline to 1-year after surgery. The smallest improvement was in the index finger (12°) and the largest improvement was in the little finger (30°). Similarly, the largest improvement in extension lag was seen in the little finger (47°) and the smallest improvement was seen in the index finger (21°). In terms of MCPJ arc of motion, all fingers moved to a more extended posture and gained an improved arc of motion, but the biggest improvement was observed in the 2 ulnar fingers and less so in the 2 radial fingers. Conclusions Our hypothesis that the ulnar fingers will have worse outcomes than the radial fingers is not proven by this study. Although past experiences have indicated that it is more difficult to maintain posture for the ring and little fingers after SMPA due to the deforming forces, sufficient correction of the deformities in the ulnar fingers is possible, if attention to adequate bone resection and realigning of the extensor mechanism are carefully performed during the procedure. PMID:19896008

Changes in the flexor digitorum profundus tendon geometry in the carpal tunnel due to force production and posture of metacarpophalangeal joint of the index finger: an MRI study.

PubMed

Martin, Joel R; Paclet, Florent; Latash, Mark L; Zatsiorsky, Vladimir M

2013-02-01

Carpal tunnel syndrome is a disorder caused by increased pressure in the carpal tunnel associated with repetitive, stereotypical finger actions. Little is known about in vivo geometrical changes in the carpal tunnel caused by motion at the finger joints and exerting a fingertip force. The hands and forearms of five subjects were scanned using a 3.0 T magnetic resonance imaging scanner. The metacarpophalangeal joint of the index finger was placed in: flexion, neutral and extension. For each joint posture subjects either produced no active force (passive condition) or exerted a flexion force to resist a load (~4.0 N) at the fingertip (active condition). Changes in the radii of curvature, position and transverse plane area of the flexor digitorum profundus tendons at the carpal tunnel level were measured. The radius of curvature of the flexor digitorum profundus tendons, at the carpal tunnel level, was significantly affected by posture of the index finger metacarpophalangeal joint (P<0.05) and the radii was significantly different between fingers (P<0.05). Actively producing force caused a significant shift (P<0.05) in the flexor digitorum profundus tendons in the ventral (palmar) direction. No significant change in the area of an ellipse containing the flexor digitorum profundus tendons was observed between conditions. The results show that relatively small changes in the posture and force production of a single finger can lead to significant changes in the geometry of all the flexor digitorum profundus tendons in the carpal tunnel. Additionally, voluntary force production at the fingertip increases the moment arm of the FDP tendons about the wrist joint. Copyright © 2012 Elsevier Ltd. All rights reserved.

Skin strain patterns provide kinaesthetic information to the human central nervous system.

PubMed Central

Edin, B B; Johansson, N

1995-01-01

1. We investigated the contribution of skin strain-related sensory inputs to movement perception and execution in five normal volunteers. The dorsal and palmar skin of the middle phalanx and the proximal interphalangeal (PIP) joint were manipulated to generate specific strain patterns in the proximal part of the index finger. To mask sensations directly related to this manipulation, skin and deeper tissues were blocked distal to the mid-portion of the proximal phalanx of the index finger by local anaesthesia. 2. Subjects were asked to move their normal right index finger either to mimic any perceived movements of the anaesthetized finger or to touch the tip of the insentient finger. 3. All subjects readily reproduced actual movements induced by the experimenter at the anaesthetized PIP joint. However, all subjects also generated flexion movements when the experimenter did not induce actual movement but produced deformations in the sentient proximal skin that were similar to those observed during actual PIP joint flexion. Likewise, the subjects indicated extension movement at the PIP joint when strain patterns corresponding to extension movements were induced. 4. In contrast, when the skin strain in the proximal part of the index finger was damped by a ring applied just proximal to the PIP joint within the anaesthetized skin area, both tested subjects failed to perceive PIP movements that actually took place.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 2 Figure 3 PMID:7473253

[Microsurgery for severe flexion contracture of proximal interphalangeal joint].

PubMed

Fei, Xiaoxuan; Feng, Shiming; Gao, Shunhong

2012-07-01

To investigate the clinical results of cross-finger flap combined with laterodigital pedicled skin flap for repair of severe flexion contracture of the proximal interphalangeal joint. Between October 2008 and February 2011, 11 patients (11 fingers) with severe flexion contracture of the proximal interphalangeal joint were treated with cross-finger flap combined with laterodigital pedicled skin flap. There were 7 males and 4 females, aged 20-63 years (mean, 32.6 years). The causes of injury were crush or electric-saw injury in 7 cases, burn or explosive injury in 3 cases, and electrical injury in 1 case. The locations were the index finger in 4 cases, the middle finger in 2 cases, the ring finger in 2 cases, and the little finger in 3 cases. The mean disease duration was 12.4 months (range, 6-24 months). All cases were rated as type III according to Stern classification standard. The volar tissue defect ranged from 3.0 cm x 1.5 cm to 5.0 cm x 2.5 cm, with exposed tendons, nerves, vessels, or bone after scar relaxation. The defects were repaired with cross-finger flaps (2.2 cm x 1.8 cm to 3.8 cm x 2.5 cm) combined with laterodigital pedicled skin flaps (1.5 cm x 1.2 cm to 2.5 cm x 2.0 cm). Double laterodigital pedicled skin flaps were used in 3 cases. The flap donor site was sutured directly or repaired with the skin graft. All flaps survived completely and wound healed by first intention. The donor skin graft survived. All the patients were followed up 6-18 months (mean, 11.3 months). The finger appearance was satisfactory. The flaps had soft texture and good color in all cases. No obvious pigmentation or contraction was observed. The contracted fingers could extend completely with good active flexion and extension motion. At last follow-up, the extension of the proximal interphalangeal joint was 10-150. Based on proximal interphalangeal joint motion standard of Chinese Medical Association for hand surgery, the results were excellent in 6 cases, good in 4 cases, and fair in 1 case; the excellent and good rate was 90.9%. It is an easy and simple therapy t o cover wound area of severe flexion contracture of the proximal interphalangeal joint after scar relaxation using cross-finger flap combined with laterodigital pedicled skin flap, which can repair large defect and achieve good results in finger appearance and function.

A new approach to depict bone surfaces in finger imaging using photoacoustic tomography

NASA Astrophysics Data System (ADS)

Biswas, S. K.; van Es, P.; Steenbergen, W.; Manohar, S.

2015-03-01

Imaging the vasculature close around the finger joints is of interest in the field of rheumatology. Locally increased vasculature in the synovial membrane of these joints can be a marker for rheumatoid arthritis. In previous work we showed that part of the photoacoustically induced ultrasound from the epidermis reflects on the bone surface within the finger. These reflected signals could be wrongly interpreted as new photoacoustic sources. In this work we show that a conventional ultrasound reconstruction algorithm, that considers the skin as a collection of ultrasound transmitters and the PA tomography probe as the detector array, can be used to delineate bone surfaces of a finger. This can in the future assist in the localization of the joint gaps. This can provide us with a landmark to localize the region of the inflamed synovial membrane. We test the approach on finger mimicking phantoms.

Hypothyroidism presenting as destructive arthropathy of the fingers.

PubMed Central

Gerster, J. C.; Quadri, P.; Saudan, Y.

1985-01-01

A patient presenting with destructive arthropathy of the proximal interphalangeal (PIP) joints of the hands is described. She was initially believed to have rheumatoid arthritis but non-steroidal anti-inflammatory drugs were of no help. The patient was subsequently found to have hypothyroidism and erosive osteoarthritis of the fingers. Joint swelling, pain and stiffness responded dramatically to thyroid hormone substitution. The PIP joint spaces reappeared on the radiographs within 9 months. This case suggest that hypothyroidism may induce destructive arthropathy of the finger joints. As thyroxine replacement may reverse the rheumatic complaints, hypothyroidism should be considered in the differential diagnosis of a destructive arthropathy of unclear aetiology. Images Figure 1 Figure 2 PMID:3983045

Experimental and failure analysis of the prosthetic finger joint implants

NASA Astrophysics Data System (ADS)

Naidu, Sanjiv H.

Small joint replacement arthroplasty of the hand is a well accepted surgical procedure to restore function and cosmesis in an individual with a crippled hand. Silicone elastomers have been used as prosthetic material in various small hand joints for well over three decades. Although the clinical science aspects of silicone elastomer failure are well known, the physical science aspects of prosthetic failure are scant and vague. In the following thesis, using both an animal model, and actual retrieved specimens which have failed in human service, experimental and failure analysis of silicone finger joints are presented. Fractured surfaces of retrieved silicone trapezial implants, and silicone finger joint implants were studied with both FESEM and SEM; the mode of failure for silicone trapezium is by wear polishing, whereas the finger joint implants failed either by fatigue fracture or tearing of the elastomer, or a combination of both. Thermal analysis revealed that the retrieved elastomer implants maintained its viscoelastic properties throughout the service period. In order to provide for a more functional and physiologic arthroplasty a novel finger joint (Rolamite prosthesis) is proposed using more recently developed thermoplastic polymers. The following thesis also addresses the outcome of the experimental studies of the Rolamite prosthesis in a rabbit animal model, in addition to the failure analysis of the thermoplastic polymers while in service in an in vivo synovial environment. Results of retrieved Rolamite specimens suggest that the use for thermoplastic elastomers such as block copolymer based elastomers in a synovial environment such as a mammalian joint may very well be limited.

Traumatic synovitis in a classical guitarist: a study of joint laxity.

PubMed

Bird, H A; Wright, V

1981-04-01

A classical guitarist performing for at least 5 hours each day developed a traumatic synovitis at the left wrist joint that was first erroneously considered to be rheumatoid arthritis. Comparison with members of the same guitar class suggested that unusual joint laxity of the fingers and wrist, probably inherited from the patient's father, was of more importance in the aetiology of the synovitis than a wide range of movement acquired by regular practice. Hyperextension of the metacarpophalangeal joint of the left index finger, quantified by the hyperextensometer, was less marked in the guitarists than in 100 normal individuals. This may be attributed to greater muscular control of the fingers. Lateral instability in the loaded joint may be the most important factor in the aetiology of traumatic synovitis.

Traumatic synovitis in a classical guitarist: a study of joint laxity.

PubMed Central

Bird, H A; Wright, V

1981-01-01

A classical guitarist performing for at least 5 hours each day developed a traumatic synovitis at the left wrist joint that was first erroneously considered to be rheumatoid arthritis. Comparison with members of the same guitar class suggested that unusual joint laxity of the fingers and wrist, probably inherited from the patient's father, was of more importance in the aetiology of the synovitis than a wide range of movement acquired by regular practice. Hyperextension of the metacarpophalangeal joint of the left index finger, quantified by the hyperextensometer, was less marked in the guitarists than in 100 normal individuals. This may be attributed to greater muscular control of the fingers. Lateral instability in the loaded joint may be the most important factor in the aetiology of traumatic synovitis. Images PMID:7224687

Robotic Finger Assembly

NASA Technical Reports Server (NTRS)

Ihrke, Chris A. (Inventor); Diftler, Myron A. (Inventor); Askew, Scott R. (Inventor); Linn, Douglas Martin (Inventor); Platt, Robert J., Jr. (Inventor); Bridgwater, Lyndon (Inventor); Hargrave, Brian (Inventor); Valvo, Michael C. (Inventor)

2014-01-01

A robotic hand includes a finger with first, second, and third phalanges. A first joint rotatably connects the first phalange to a base structure. A second joint rotatably connects the first phalange to the second phalange. A third joint rotatably connects the third phalange to the second phalange. The second joint and the third joint are kinematically linked such that the position of the third phalange with respect to the second phalange is determined by the position of the second phalange with respect to the first phalange.

Robotic Finger Assembly

NASA Technical Reports Server (NTRS)

Ihrke, Chris A. (Inventor); Bridgwater, Lyndon (Inventor); Diftler, Myron A. (Inventor); Linn, Douglas M. (Inventor); Platt, Robert (Inventor); Hargrave, Brian (Inventor); Askew, Scott R. (Inventor); Valvo, Michael C. (Inventor)

2013-01-01

A robotic hand includes a finger with first, second, and third phalanges. A first joint rotatably connects the first phalange to a base structure. A second joint rotatably connects the first phalange to the second phalange. A third joint rotatably connects the third phalange to the second phalange. The second joint and the third joint are kinematically linked such that the position of the third phalange with respect to the second phalange is determined by the position of the second phalange with respect to the first phalange.

Change of synovial vascularity in a single finger joint assessed by power doppler sonography correlated with radiographic change in rheumatoid arthritis: comparative study of a novel quantitative score with a semiquantitative score.

PubMed

Fukae, Jun; Kon, Yujiro; Henmi, Mihoko; Sakamoto, Fumihiko; Narita, Akihiro; Shimizu, Masato; Tanimura, Kazuhide; Matsuhashi, Megumi; Kamishima, Tamotsu; Atsumi, Tatsuya; Koike, Takao

2010-05-01

To investigate the relationship between synovial vascularity assessed by quantitative power Doppler sonography (PDS) and progression of structural bone damage in a single finger joint in patients with rheumatoid arthritis (RA). We studied 190 metacarpophalangeal (MCP) joints and 190 proximal interphalangeal (PIP) joints of 19 patients with active RA who had initial treatment with disease-modifying antirheumatic drugs (DMARDs). Patients were examined by clinical and laboratory assessments throughout the study. Hand and foot radiography was performed at baseline and the twentieth week. Magnetic resonance imaging (MRI) was performed at baseline. PDS was performed at baseline and the eighth week. Synovial vascularity was evaluated according to both quantitative and semiquantitative methods. Quantitative PDS was significantly correlated with the enhancement rate of MRI in each single finger joint. Comparing quantitative synovial vascularity and radiographic change in single MCP or PIP joints, the level of vascularity at baseline showed a significant positive correlation with radiographic progression at the twentieth week. The change of vascularity in response to DMARDs, defined as the percentage change in vascularity by the eighth week from baseline, was inversely correlated with radiographic progression in each MCP joint. The quantitative PDS method was more useful than the semiquantitative method for the evaluation of synovial vascularity in a single finger joint. The change of synovial vascularity in a single finger joint determined by quantitative PDS could numerically predict its radiographic progression. Using vascularity as a guide to consider a therapeutic approach would have benefits for patients with active RA.

Control of an optimal finger exoskeleton based on continuous joint angle estimation from EMG signals.

PubMed

Ngeo, Jimson; Tamei, Tomoya; Shibata, Tomohiro; Orlando, M F Felix; Behera, Laxmidhar; Saxena, Anupam; Dutta, Ashish

2013-01-01

Patients suffering from loss of hand functions caused by stroke and other spinal cord injuries have driven a surge in the development of wearable assistive devices in recent years. In this paper, we present a system made up of a low-profile, optimally designed finger exoskeleton continuously controlled by a user's surface electromyographic (sEMG) signals. The mechanical design is based on an optimal four-bar linkage that can model the finger's irregular trajectory due to the finger's varying lengths and changing instantaneous center. The desired joint angle positions are given by the predictive output of an artificial neural network with an EMG-to-Muscle Activation model that parameterizes electromechanical delay (EMD). After confirming good prediction accuracy of multiple finger joint angles we evaluated an index finger exoskeleton by obtaining a subject's EMG signals from the left forearm and using the signal to actuate a finger on the right hand with the exoskeleton. Our results show that our sEMG-based control strategy worked well in controlling the exoskeleton, obtaining the intended positions of the device, and that the subject felt the appropriate motion support from the device.

Computer-aided classification of rheumatoid arthritis in finger joints using frequency domain optical tomography

NASA Astrophysics Data System (ADS)

Klose, C. D.; Kim, H. K.; Netz, U.; Blaschke, S.; Zwaka, P. A.; Mueller, G. A.; Beuthan, J.; Hielscher, A. H.

2009-02-01

Novel methods that can help in the diagnosis and monitoring of joint disease are essential for efficient use of novel arthritis therapies that are currently emerging. Building on previous studies that involved continuous wave imaging systems we present here first clinical data obtained with a new frequency-domain imaging system. Three-dimensional tomographic data sets of absorption and scattering coefficients were generated for 107 fingers. The data were analyzed using ANOVA, MANOVA, Discriminant Analysis DA, and a machine-learning algorithm that is based on self-organizing mapping (SOM) for clustering data in 2-dimensional parameter spaces. Overall we found that the SOM algorithm outperforms the more traditional analysis methods in terms of correctly classifying finger joints. Using SOM, healthy and affected joints can now be separated with a sensitivity of 0.97 and specificity of 0.91. Furthermore, preliminary results suggest that if a combination of multiple image properties is used, statistical significant differences can be found between RA-affected finger joints that show different clinical features (e.g. effusion, synovitis or erosion).

Cortex Inspired Model for Inverse Kinematics Computation for a Humanoid Robotic Finger

PubMed Central

Gentili, Rodolphe J.; Oh, Hyuk; Molina, Javier; Reggia, James A.; Contreras-Vidal, José L.

2013-01-01

In order to approach human hand performance levels, artificial anthropomorphic hands/fingers have increasingly incorporated human biomechanical features. However, the performance of finger reaching movements to visual targets involving the complex kinematics of multi-jointed, anthropomorphic actuators is a difficult problem. This is because the relationship between sensory and motor coordinates is highly nonlinear, and also often includes mechanical coupling of the two last joints. Recently, we developed a cortical model that learns the inverse kinematics of a simulated anthropomorphic finger. Here, we expand this previous work by assessing if this cortical model is able to learn the inverse kinematics for an actual anthropomorphic humanoid finger having its two last joints coupled and controlled by pneumatic muscles. The findings revealed that single 3D reaching movements, as well as more complex patterns of motion of the humanoid finger, were accurately and robustly performed by this cortical model while producing kinematics comparable to those of humans. This work contributes to the development of a bioinspired controller providing adaptive, robust and flexible control of dexterous robotic and prosthetic hands. PMID:23366569

High-resolution x-ray guided three-dimensional diffuse optical tomography of joint tissues in hand osteoarthritis: Morphological and functional assessments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuan Zhen; Zhang Qizhi; Sobel, Eric S.

Purpose: The aim of this study was to investigate the potential use of multimodality functional imaging techniques to identify the quantitative optical findings that can be used to distinguish between osteoarthritic and normal finger joints. Methods: Between 2006 and 2009, the distal interphalangeal finger joints from 40 female subjects including 22 patients and 18 healthy controls were examined clinically and scanned by a hybrid imaging system. This system integrated x-ray tomosynthetic setup with a diffuse optical imaging system. Optical absorption and scattering images were recovered based on a regularization-based hybrid reconstruction algorithm. A receiver operating characteristic curve was used tomore » calculate the statistical significance of specific optical features obtained from osteoarthritic and healthy joints groups. Results: The three-dimensional optical and x-ray images captured made it possible to quantify optical properties and joint space width of finger joints. Based on the recovered optical absorption and scattering parameters, the authors observed statistically significant differences between healthy and osteoarthritis finger joints. Conclusions: The statistical results revealed that sensitivity and specificity values up to 92% and 100%, respectively, can be achieved when optical properties of joint tissues were used as classifiers. This suggests that these optical imaging parameters are possible indicators for diagnosing osteoarthritis and monitoring its progression.« less

A cortically-inspired model for inverse kinematics computation of a humanoid finger with mechanically coupled joints.

PubMed

Gentili, Rodolphe J; Oh, Hyuk; Kregling, Alissa V; Reggia, James A

2016-05-19

The human hand's versatility allows for robust and flexible grasping. To obtain such efficiency, many robotic hands include human biomechanical features such as fingers having their two last joints mechanically coupled. Although such coupling enables human-like grasping, controlling the inverse kinematics of such mechanical systems is challenging. Here we propose a cortical model for fine motor control of a humanoid finger, having its two last joints coupled, that learns the inverse kinematics of the effector. This neural model functionally mimics the population vector coding as well as sensorimotor prediction processes of the brain's motor/premotor and parietal regions, respectively. After learning, this neural architecture could both overtly (actual execution) and covertly (mental execution or motor imagery) perform accurate, robust and flexible finger movements while reproducing the main human finger kinematic states. This work contributes to developing neuro-mimetic controllers for dexterous humanoid robotic/prosthetic upper-extremities, and has the potential to promote human-robot interactions.

Hand rehabilitation after stroke using a wearable, high DOF, spring powered exoskeleton.

PubMed

Tianyao Chen; Lum, Peter S

2016-08-01

Stroke patients often have inappropriate finger flexor activation and finger extensor weakness, which makes it difficult to open their affected hand for functional grasp. The goal was to develop a passive, lightweight, wearable device to enable improved hand function during performance of activities of daily living. The device, HandSOME II, assists with opening the patient's hand using 11 elastic actuators that apply extension torques to finger and thumb joints. Device design and initial testing are described. A novel mechanical design applies forces orthogonal to the finger segments despite the fact that all of the device DOFs are not aligned with human joint DOF. In initial testing with seven stroke subjects with impaired hand function, use of HandSOME II significantly increased maximum extension angles and range of motion in all of the index finger joints (P<;0.05). HandSOME II allows performance of all the grip patterns used in daily activities and can be used as part of home-based therapy programs.

SU-E-T-171: Evaluation of the Analytical Anisotropic Algorithm in a Small Finger Joint Phantom Using Monte Carlo Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chow, J; Owrangi, A; Jiang, R

2014-06-01

Purpose: This study investigated the performance of the anisotropic analytical algorithm (AAA) in dose calculation in radiotherapy concerning a small finger joint. Monte Carlo simulation (EGSnrc code) was used in this dosimetric evaluation. Methods: Heterogeneous finger joint phantom containing a vertical water layer (bone joint or cartilage) sandwiched by two bones with dimension 2 × 2 × 2 cm{sup 3} was irradiated by the 6 MV photon beams (field size = 4 × 4 cm{sup 2}). The central beam axis was along the length of the bone joint and the isocenter was set to the center of the joint. Themore » joint width and beam angle were varied from 0.5–2 mm and 0°–15°, respectively. Depth doses were calculated using the AAA and DOSXYZnrc. For dosimetric comparison and normalization, dose calculations were repeated in water phantom using the same beam geometry. Results: Our AAA and Monte Carlo results showed that the AAA underestimated the joint doses by 10%–20%, and could not predict joint dose variation with changes of joint width and beam angle. The calculated bone dose enhancement for the AAA was lower than Monte Carlo and the depth of maximum dose for the phantom was smaller than that for the water phantom. From Monte Carlo results, there was a decrease of joint dose as its width increased. This reflected the smaller the joint width, the more the bone scatter contributed to the depth dose. Moreover, the joint dose was found slightly decreased with an increase of beam angle. Conclusion: The AAA could not handle variations of joint dose well with changes of joint width and beam angle based on our finger joint phantom. Monte Carlo results showed that the joint dose decreased with increase of joint width and beam angle. This dosimetry comparison should be useful to radiation staff in radiotherapy related to small bone joint.« less

Distinct Inter-Joint Coordination during Fast Alternate Keystrokes in Pianists with Superior Skill.

PubMed

Furuya, Shinichi; Goda, Tatsushi; Katayose, Haruhiro; Miwa, Hiroyoshi; Nagata, Noriko

2011-01-01

Musical performance requires motor skills to coordinate the movements of multiple joints in the hand and arm over a wide range of tempi. However, it is unclear whether the coordination of movement across joints would differ for musicians with different skill levels and how inter-joint coordination would vary in relation to music tempo. The present study addresses these issues by examining the kinematics and muscular activity of the hand and arm movements of professional and amateur pianists who strike two keys alternately with the thumb and little finger at various tempi. The professionals produced a smaller flexion velocity at the thumb and little finger and greater elbow pronation and supination velocity than did the amateurs. The experts also showed smaller extension angles at the metacarpo-phalangeal joint of the index and middle fingers, which were not being used to strike the keys. Furthermore, muscular activity in the extrinsic finger muscles was smaller for the experts than for the amateurs. These findings indicate that pianists with superior skill reduce the finger muscle load during keystrokes by taking advantage of differences in proximal joint motion and hand postural configuration. With an increase in tempo, the experts showed larger and smaller increases in elbow velocity and finger muscle co-activation, respectively, compared to the amateurs, highlighting skill level-dependent differences in movement strategies for tempo adjustment. Finally, when striking as fast as possible, individual differences in the striking tempo among players were explained by their elbow velocities but not by their digit velocities. These findings suggest that pianists who are capable of faster keystrokes benefit more from proximal joint motion than do pianists who are not capable of faster keystrokes. The distinct movement strategy for tempo adjustment in pianists with superior skill would therefore ensure a wider range of musical expression.

Distinct Inter-Joint Coordination during Fast Alternate Keystrokes in Pianists with Superior Skill

PubMed Central

Furuya, Shinichi; Goda, Tatsushi; Katayose, Haruhiro; Miwa, Hiroyoshi; Nagata, Noriko

2011-01-01

Musical performance requires motor skills to coordinate the movements of multiple joints in the hand and arm over a wide range of tempi. However, it is unclear whether the coordination of movement across joints would differ for musicians with different skill levels and how inter-joint coordination would vary in relation to music tempo. The present study addresses these issues by examining the kinematics and muscular activity of the hand and arm movements of professional and amateur pianists who strike two keys alternately with the thumb and little finger at various tempi. The professionals produced a smaller flexion velocity at the thumb and little finger and greater elbow pronation and supination velocity than did the amateurs. The experts also showed smaller extension angles at the metacarpo-phalangeal joint of the index and middle fingers, which were not being used to strike the keys. Furthermore, muscular activity in the extrinsic finger muscles was smaller for the experts than for the amateurs. These findings indicate that pianists with superior skill reduce the finger muscle load during keystrokes by taking advantage of differences in proximal joint motion and hand postural configuration. With an increase in tempo, the experts showed larger and smaller increases in elbow velocity and finger muscle co-activation, respectively, compared to the amateurs, highlighting skill level-dependent differences in movement strategies for tempo adjustment. Finally, when striking as fast as possible, individual differences in the striking tempo among players were explained by their elbow velocities but not by their digit velocities. These findings suggest that pianists who are capable of faster keystrokes benefit more from proximal joint motion than do pianists who are not capable of faster keystrokes. The distinct movement strategy for tempo adjustment in pianists with superior skill would therefore ensure a wider range of musical expression. PMID:21660290

SEPs to finger joint input lack the N20-P20 response that is evoked by tactile inputs: contrast between cortical generators in areas 3b and 2 in humans.

PubMed

Desmedt, J E; Ozaki, I

1991-01-01

A method using a DC servo motor is described to produce brisk angular movements at finger interphalangeal joints in humans. Small passive flexions of 2 degrees elicited sizable somatosensory evoked potentials (SEPs) starting with a contralateral positive P34 parietal response thought to reflect activation of a radial equivalent dipole generator in area 2 which receives joint inputs. By contrast, electric stimulation of tactile (non-joint) inputs from the distal phalanx evoked the usual contralateral negative N20 reflecting a tangential equivalent dipole generator in area 3b. Finger joint inputs also evoked a precentral positivity equivalent to the P22 of motor area 4, and a large frontal negativity equivalent to N30. It is suggested that natural stimulation allows human SEP components to be differentiated in conjunction with distinct cortical somatotopic projections.

Distractor objects affect fingers' angular distances but not fingers' shaping during grasping.

PubMed

Ansuini, Caterina; Tognin, Veronica; Turella, Luca; Castiello, Umberto

2007-04-01

The aim of the present study was to determine whether and how hand shaping was affected by the presence of a distractor object adjacent to the to-be-grasped object. Twenty subjects were requested to reach towards and grasp a 'convex' or a 'concave' object in the presence or absence of a distractor object either of the same or different shape than the target object. Flexion/extension at the metacarpal-phalangeal (MCP) and proximal interphalangeal joints of all digits, and abduction angle between digits were measured by resistive sensors embedded in a glove. The results indicate robust interference effects at the level of reach duration and the extent of fingers' abduction angles together with changes at the level of a single joint for the thumb. No distractor effects on individual fingers' joints except for the MCP of the middle and little fingers were found. These findings suggest that the presence of distractor object affects hand shaping in terms of fingers' abduction angles, but not at the level of 'shape dependent' fingers' angular excursions. Furthermore, they support the importance of the thumb for the guidance of selective reach-to-grasp movements. We discuss these results in the context of current theories proposed to explain the object selection processes underlying the control of hand action.

Radiographic hand osteoarthritis: patterns and associations with hand pain and function in a community-dwelling sample.

PubMed

Marshall, M; van der Windt, D; Nicholls, E; Myers, H; Hay, E; Dziedzic, K

2009-11-01

Patterns of radiographic osteoarthritis (ROA) of the hand are often examined by row, with the four joints of the thumb studied inconsistently. The objectives of this study were to determine relationships of ROA at different hand joints, use the findings to define radiographic sub-groups and investigate their associations with pain and function. Sixteen joints in each hand were scored for the presence of ROA in a community-dwelling cohort of adults, 50-years-and-over, with self-reported hand pain or problems. Principal components analysis (PCA) with varimax rotation was used to study patterns of ROA in the hand joints and identify distinct sub-groups. Differences in pain and function between these sub-groups were assessed using Australian/Canadian Osteoarthritis Index (AUSCAN), Grip Ability Test (GAT) and grip and pinch strength. PCA was undertaken on data from 592 participants and identified four components: distal interphalangeal joints (DIPs), proximal interphalangeal joints (PIPs), metacarpophalangeal joints (MCPs), thumb joints. However, the left thumb interphalangeal (IP) joint cross-loaded with the PIP and thumb groups. On this basis, participants were categorised into four radiographic sub-groups: no osteoarthritis (OA), finger only OA, thumb only OA and combined thumb and finger OA. Statistically significant differences were found between the sub-groups for AUSCAN function, and in women alone for grip and pinch strength. Participants with combined thumb and finger OA had the worst scores. Individual thumb joints can be clustered together as a joint group in ROA. Four radiographic sub-groups of hand OA can be distinguished. Pain and functional difficulties were highest in participants with both thumb and finger OA.

Initial results of finger imaging using photoacoustic computed tomography

NASA Astrophysics Data System (ADS)

van Es, Peter; Biswas, Samir K.; Moens, Hein J. Bernelot; Steenbergen, Wiendelt; Manohar, Srirang

2014-06-01

We present a photoacoustic computed tomography investigation on a healthy human finger, to image blood vessels with a focus on vascularity across the interphalangeal joints. The cross-sectional images were acquired using an imager specifically developed for this purpose. The images show rich detail of the digital blood vessels with diameters between 100 μm and 1.5 mm in various orientations and at various depths. Different vascular layers in the skin including the subpapillary plexus could also be visualized. Acoustic reflections on the finger bone of photoacoustic signals from skin were visible in sequential slice images along the finger except at the location of the joint gaps. Not unexpectedly, the healthy synovial membrane at the joint gaps was not detected due to its small size and normal vascularization. Future research will concentrate on studying digits afflicted with rheumatoid arthritis to detect the inflamed synovium with its heightened vascularization, whose characteristics are potential markers for disease activity.

Simulation of light transport in arthritic- and non-arthritic human fingers

NASA Astrophysics Data System (ADS)

Milanic, Matija; Paluchowski, Lukasz A.; Randeberg, Lise L.

2014-03-01

Rheumatoid arthritis is a disease that frequently leads to joint destruction. It has high incidence rates worldwide, and the disease significantly reduces patient's quality of life due to pain, swelling and stiffness of the affected joints. Early diagnosis is necessary to improve course of the disease, therefore sensitive and accurate diagnostic tools are required. Optical imaging techniques have capability for early diagnosis and monitoring of arthritis. As compared to conventional diagnostic techniques optical technique is a noninvasive, noncontact and fast way of collecting diagnostic information. However, a realistic model of light transport in human joints is needed for understanding and developing of such optical diagnostic tools. The aim of this study is to develop a 3D numerical model of light transport in a human finger. The model will guide development of a hyperspectral imaging (HSI) diagnostic modality for arthritis in human fingers. The implemented human finger geometry is based on anatomical data. Optical data of finger tissues are adjusted to represent either an arthritic or an unaffected finger. The geometry and optical data serve as input into a 3D Monte Carlo method, which calculate diffuse reflectance, transmittance and absorbed energy distributions. The parameters of the model are optimized based on HIS-measurements of human fingers. The presented model serves as an important tool for understanding and development of HSI as an arthritis diagnostic modality. Yet, it can be applied to other optical techniques and finger diseases.

Reoperations following proximal interphalangeal joint nonconstrained arthroplasties.

PubMed

Pritsch, Tamir; Rizzo, Marco

2011-09-01

To retrospectively analyze the reasons for reoperations following primary nonconstrained proximal interphalangeal (PIP) joint arthroplasty and review clinical outcomes in this group of patients with 1 or more reoperations. Between 2001 and 2009, 294 nonconstrained (203 pyrocarbon and 91 metal-plastic) PIP joint replacements were performed in our institution. A total of 76 fingers (59 patients) required reoperation (50 pyrocarbon and 26 metal-plastic). There were 40 women and 19 men with an average age of 51 years (range, 19-83 y). Primary diagnoses included osteoarthritis in 35, posttraumatic arthritis in 24, and inflammatory arthritis in 17 patients. There were 21 index, 27 middle, 18 ring, and 10 small fingers. The average number of reoperations per PIP joint was 1.6 (range, 1-4). A total of 45 joints had 1 reoperation, 19 had 2, 11 had 3, and 1 had 4. Extensor mechanism dysfunction was the most common reason for reoperation; it involved 51 of 76 fingers and was associated with Chamay or tendon-reflecting surgical approaches. Additional etiologies included component loosening in 17, collateral ligament failure in 10, and volar plate contracture in 8 cases. Inflammatory arthritis was associated with collateral ligament failure. Six fingers were eventually amputated, 9 had PIP joint arthrodeses, and 2 had resection arthroplasties. The arthrodesis and amputation rates correlated with the increased number of reoperations per finger. Clinically, most patients had no or mild pain at the most recent follow-up, and the PIP joint range-of-motion was not significantly different from preoperative values. Pain levels improved with longer follow-up. Reoperations following primary nonconstrained PIP joint arthroplasties are common. Extensor mechanism dysfunction was the most common reason for reoperation. The average reoperation rate was 1.6, and arthrodesis and amputation are associated with an increasing number of operations. Overall clinical outcomes demonstrated no significant change in range of motion, and most patients had mild or no pain. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Losing dexterity: patterns of impaired coordination of finger movements in musician’s dystonia

PubMed Central

Furuya, Shinichi; Tominaga, Kenta; Miyazaki, Fumio; Altenmüller, Eckart

2015-01-01

Extensive training can bring about highly-skilled action, but may also impair motor dexterity by producing involuntary movements and muscular cramping, as seen in focal dystonia (FD) and tremor. To elucidate the underlying neuroplastic mechanisms of FD, the present study addressed the organization of finger movements during piano performance in pianists suffering from the condition. Principal component (PC) analysis identified three patterns of fundamental joint coordination constituting finger movements in both patients and controls. The first two coordination patterns described less individuated movements between the “dystonic” finger and key-striking fingers for patients compared to controls. The third coordination pattern, representing the individuation of movements between the middle and ring fingers, was evident during a sequence of strikes with these fingers in controls, which was absent in the patients. Consequently, rhythmic variability of keystrokes was more pronounced during this sequence of strikes for the patients. A stepwise multiple-regression analysis further identified greater variability of keystrokes for individuals displaying less individuated movements between the affected and striking fingers. The findings suggest that FD alters dexterous joint coordination so as to lower independent control of finger movements, and thereby degrades fine motor control. PMID:26289433

Use of the shape memory polymer polystyrene in the creation of thin film stretchable sensors for wearable applications

NASA Astrophysics Data System (ADS)

Van Volkinburg, Kyle R.; Nguyen, Thao; Pegan, Jonathan D.; Khine, Michelle; Washington, Gregory N.

2016-04-01

The shape memory polymer polystyrene (PS) has been used to create complex hierarchical wrinkling in the fabrication of stretchable thin film bimetallic sensors ideal for wearable based gesture monitoring applications. The film has been bonded to the elastomer polydimethylsiloxane (PDMS) and operates as a strain gauge under the general notion of geometric piezoresistivity. The film was subject to tensile, cyclic, and step loading conditions in order to characterize its dynamic behavior. To measure the joint angle of the metacarpophalangeal (MCP) joint on the right index finger, the sensor was adhered to a fitted golf glove above said joint and a motion study was conducted. At maximum joint angle the sensor experienced roughly 23.5% strain. From the study it was found that two simple curves, one while the finger was in flexion and the other while the finger was in extension, were able to predict the joint angle from measured voltage with an average error of 2.99 degrees.

Exploration of Hand Grasp Patterns Elicitable Through Non-Invasive Proximal Nerve Stimulation.

PubMed

Shin, Henry; Watkins, Zach; Hu, Xiaogang

2017-11-29

Various neurological conditions, such as stroke or spinal cord injury, result in an impaired control of the hand. One method of restoring this impairment is through functional electrical stimulation (FES). However, traditional FES techniques often lead to quick fatigue and unnatural ballistic movements. In this study, we sought to explore the capabilities of a non-invasive proximal nerve stimulation technique in eliciting various hand grasp patterns. The ulnar and median nerves proximal to the elbow joint were activated transcutanously using a programmable stimulator, and the resultant finger flexion joint angles were recorded using a motion capture system. The individual finger motions averaged across the three joints were analyzed using a cluster analysis, in order to classify the different hand grasp patterns. With low current intensity (<5 mA and 100 µs pulse width) stimulation, our results show that all of our subjects demonstrated a variety of consistent hand grasp patterns including single finger movement and coordinated multi-finger movements. This study provides initial evidence on the feasibility of a proximal nerve stimulation technique in controlling a variety of finger movements and grasp patterns. Our approach could also be developed into a rehabilitative/assistive tool that can result in flexible movements of the fingers.

Compact Telerobot Hand

NASA Technical Reports Server (NTRS)

Rosheim, Mark; Trechsel, Hans

1993-01-01

Anthropomorphic telerobotic hand contains actuators, joints, sensors, and complex wiring harnesses. Glove protects interior components of hand from dirt and damage. Imitates motions of human fingers and wrist in lifelike and dexterous way. Incorporates pitch/yaw joints in wrist and head knuckles. Hand modular; so fingers removable, interchangeable units. Feature simplifies servicing and maintenance, which must be done frequently in such complex mechanism.

A Soft Sensor-Based Three-Dimensional (3-D) Finger Motion Measurement System

PubMed Central

Park, Wookeun; Ro, Kyongkwan; Kim, Suin; Bae, Joonbum

2017-01-01

In this study, a soft sensor-based three-dimensional (3-D) finger motion measurement system is proposed. The sensors, made of the soft material Ecoflex, comprise embedded microchannels filled with a conductive liquid metal (EGaln). The superior elasticity, light weight, and sensitivity of soft sensors allows them to be embedded in environments in which conventional sensors cannot. Complicated finger joints, such as the carpometacarpal (CMC) joint of the thumb are modeled to specify the location of the sensors. Algorithms to decouple the signals from soft sensors are proposed to extract the pure flexion, extension, abduction, and adduction joint angles. The performance of the proposed system and algorithms are verified by comparison with a camera-based motion capture system. PMID:28241414

Rotational stability test for the diagnosis of radial collateral ligament rupture in the fingers: Anatomical study.

PubMed

Lazarus, P; Hidalgo Diaz, J J; Prunières, G; Pire, E; Taleb, C; Honecker, S; Bellemère, P; Fontaine, C; Liverneaux, P A

2017-04-01

Diagnosing rupture of the radial collateral ligament (RCL) of the finger metacarpophalangeal (MCP) joints is difficult. The aim of this cadaver study was to validate a rotational test for the MCP after RCL transection. With the MCP and proximal interphalangeal joints in flexion, rotation along the axis of the proximal phalanx was applied through an extended distal interphalangeal joint to 36 cadaver fingers. Each finger's pulp described an arc of pronation and supination that was noted on the palm. The test was repeated three times: before transection, after transection of the proper collateral ligament (CL) and after transection of both the proper and accessory CLs. Rotational arcs were measured in pronation and supination. Mean length of the pronation arc after transection of the main RCL was 17.53mm, while it was only 12.41mm before transection for the supination arc. Mean length of the pronation arc after transection of both CLs was 22.83mm compared to only 11.93mm before transection. Our results show a significant difference in pronation stability of the MCP joint after transection of the RCL proper. We can conclude that this rotational stability test is a valid test for diagnosing RCL rupture in MCP joints. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

Automatic finger joint synovitis localization in ultrasound images

NASA Astrophysics Data System (ADS)

Nurzynska, Karolina; Smolka, Bogdan

2016-04-01

A long-lasting inflammation of joints results between others in many arthritis diseases. When not cured, it may influence other organs and general patients' health. Therefore, early detection and running proper medical treatment are of big value. The patients' organs are scanned with high frequency acoustic waves, which enable visualization of interior body structures through an ultrasound sonography (USG) image. However, the procedure is standardized, different projections result in a variety of possible data, which should be analyzed in short period of time by a physician, who is using medical atlases as a guidance. This work introduces an efficient framework based on statistical approach to the finger joint USG image, which enables automatic localization of skin and bone regions, which are then used for localization of the finger joint synovitis area. The processing pipeline realizes the task in real-time and proves high accuracy when compared to annotation prepared by the expert.

Evaluation of the Sensitivity and Specificity of the New Clinical Diagnostic and Classification Criteria for Kashin-Beck Disease, an Endemic Osteoarthritis, in China.

PubMed

Yu, Fang Fang; Ping, Zhi Guang; Yao, Chong; Wang, Zhi Wen; Wang, Fu Qi; Guo, Xiong

2017-02-01

This study aimed to evaluate the sensitivity and specificity of the new clinical diagnostic and classification criteria for Kashin-Beck disease (KBD) using six clinical markers: flexion of the distal part of fingers, deformed fingers, enlarged finger joints, shortened fingers, squat down, and dwarfism. One-third of the total population in Linyou County was sampled by stratified random sampling. The survey included baseline characteristics and clinical diagnoses, and the sensitivity and specificity of the new criteria was evaluated. We identified 3,459 KBD patients, of which 69 had early stage KBD, 1,952 had stage I, 1,132 had stage II, and 306 had stage III. A screening test classified enlarged finger joints as stage I KBD, with a sensitivity and specificity of 0.978 and 0.045, respectively. Shortened fingers were classified as stage II KBD, with a sensitivity and specificity of 0.969 and 0.844, respectively, and dwarfism was classified as stage III KBD with a sensitivity and specificity of 0.951 and 0.992, respectively. Serial screening test revealed that the new clinical classification of KBD classified stages I, II, and III KBD with sensitivities of 0.949, 0.945, and 0.925 and specificities of 0.967, 0.970, and 0.993, respectively. The screening tests revealed that enlarged finger joints, shortened fingers, and dwarfism were appropriate markers for the clinical diagnosis and classification of KBD with high sensitivity and specificity. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

The wear of cross-linked polyethylene against itself.

PubMed

Joyce, T J; Ash, H E; Unsworth, A

1996-01-01

Cross-linked polyethylene (XLPE) may have an application as a material for an all-plastic surface replacement finger joint. It is inexpensive, biocompatible and can be injection-moulded into the complex shapes that are found on the ends of the finger bones. Further, the cross-linking of polyethylene has significantly improved its mechanical properties. Therefore, the opportunity exists for an all-XLPE joint, and so the wear characteristics of XLPE sliding against itself have been investigated. Wear tests were carried out on both reciprocating pin-on-plate machines and a finger function simulator. The reciprocating pin-on-plate machines had pins loaded at 10 N and 40 N. All pin-on-plate tests show wear factors from the plates very much greater than those of the pins. After 349 km of sliding, a mean wear factor of 0.46 x 10(-6) mm3/N m was found for the plates compared with 0.021 x 10(-6) mm3/N m for the pins. A fatigue mechanism may be causing this phenomenon of greater plate wear. Tests using the finger function simulator give an average wear rate of 0.22 x 10(-6) mm3/N m after 368 km. This sliding distance is equivalent to 12.5 years of use in vivo. The wear factors found were comparable with those of ultra-high molecular weight polyethylene (UHMWPE) against a metallic counterface and, therefore, as the loads across the finger joint are much less than those across the knee or the hip, it is probable that an all-XLPE finger joint will be viable from a wear point of view.

Reliability of the standard goniometry and diagrammatic recording of finger joint angles: a comparative study with healthy subjects and non-professional raters.

PubMed

Macionis, Valdas

2013-01-09

Diagrammatic recording of finger joint angles by using two criss-crossed paper strips can be a quick substitute to the standard goniometry. As a preliminary step toward clinical validation of the diagrammatic technique, the current study employed healthy subjects and non-professional raters to explore whether reliability estimates of the diagrammatic goniometry are comparable with those of the standard procedure. The study included two procedurally different parts, which were replicated by assigning 24 medical students to act interchangeably as 12 subjects and 12 raters. A larger component of the study was designed to compare goniometers side-by-side in measurement of finger joint angles varying from subject to subject. In the rest of the study, the instruments were compared by parallel evaluations of joint angles similar for all subjects in a situation of simulated change of joint range of motion over time. The subjects used special guides to position the joints of their left ring finger at varying angles of flexion and extension. The obtained diagrams of joint angles were converted to numerical values by computerized measurements. The statistical approaches included calculation of appropriate intraclass correlation coefficients, standard errors of measurements, proportions of measurement differences of 5 or less degrees, and significant differences between paired observations. Reliability estimates were similar for both goniometers. Intra-rater and inter-rater intraclass correlation coefficients ranged from 0.69 to 0.93. The corresponding standard errors of measurements ranged from 2.4 to 4.9 degrees. Repeated measurements of a considerable number of raters fell within clinically non-meaningful 5 degrees of each other in proportions comparable with a criterion value of 0.95. Data collected with both instruments could be similarly interpreted in a simulated situation of change of joint range of motion over time. The paper goniometer and the standard goniometer can be used interchangeably by non-professional raters for evaluation of normal finger joints. The obtained results warrant further research to assess clinical performance of the paper strip technique.

Reliability of the standard goniometry and diagrammatic recording of finger joint angles: a comparative study with healthy subjects and non-professional raters

PubMed Central

2013-01-01

Background Diagrammatic recording of finger joint angles by using two criss-crossed paper strips can be a quick substitute to the standard goniometry. As a preliminary step toward clinical validation of the diagrammatic technique, the current study employed healthy subjects and non-professional raters to explore whether reliability estimates of the diagrammatic goniometry are comparable with those of the standard procedure. Methods The study included two procedurally different parts, which were replicated by assigning 24 medical students to act interchangeably as 12 subjects and 12 raters. A larger component of the study was designed to compare goniometers side-by-side in measurement of finger joint angles varying from subject to subject. In the rest of the study, the instruments were compared by parallel evaluations of joint angles similar for all subjects in a situation of simulated change of joint range of motion over time. The subjects used special guides to position the joints of their left ring finger at varying angles of flexion and extension. The obtained diagrams of joint angles were converted to numerical values by computerized measurements. The statistical approaches included calculation of appropriate intraclass correlation coefficients, standard errors of measurements, proportions of measurement differences of 5 or less degrees, and significant differences between paired observations. Results Reliability estimates were similar for both goniometers. Intra-rater and inter-rater intraclass correlation coefficients ranged from 0.69 to 0.93. The corresponding standard errors of measurements ranged from 2.4 to 4.9 degrees. Repeated measurements of a considerable number of raters fell within clinically non-meaningful 5 degrees of each other in proportions comparable with a criterion value of 0.95. Data collected with both instruments could be similarly interpreted in a simulated situation of change of joint range of motion over time. Conclusions The paper goniometer and the standard goniometer can be used interchangeably by non-professional raters for evaluation of normal finger joints. The obtained results warrant further research to assess clinical performance of the paper strip technique. PMID:23302419

A Prospective Study of Injuries and Injury Risk Factors Among Army Wheel Vehicle Mechanics

DTIC Science & Technology

2006-08-01

metacarpalphalangeal joint and 110* at the proximal interphalangeal joint of the third finger . While keeping the forearm on the padded table surface...ground, then return to the starting point with elbows fully extended. For sit-up, the Soldier bent his knees at a 90’ angle, interlocked his fingers ...Wrist 5 5.4 Hand 2 2.2 Finger 3 3.3 Upper Back 1 1.1 Lower Back Lower Back 16 17.4 Pelvic Area 1 1.1 Anterior Thigh 1 1.1 Knee 17 18.5 Lower Body Calf 1

Speed invariance of independent control of finger movements in pianists

PubMed Central

Soechting, John F.

2012-01-01

Independent control of finger movements characterizes skilled motor behaviors such as tool use and musical performance. The purpose of the present study was to identify the effect of movement frequency (tempo) on individuated finger movements in piano playing. Joint motion at the digits was recorded while 5 expert pianists were playing 30 excerpts from musical pieces with different fingering and key locations either at a predetermined normal tempo or as fast as possible. Principal component analysis and cluster analysis using an expectation-maximization algorithm determined three distinct patterns of finger movement coordination for a keypress with each of the index, middle, ring, and little fingers at each of the two tempi. The finger kinematics of each coordination pattern was overall similar across the tempi. Tone sequences assigned into each cluster were also similar for both tempi. A linear regression analysis determined no apparent difference in the amount of movement covariation between the striking and nonstriking fingers at both metacarpo-phalangeal and proximal-interphalangeal joints across the two tempi, which indicated no effect of tempo on independent finger movements in piano playing. In addition, the standard deviation of interkeystroke interval across strokes did not differ between the two tempi, indicating maintenance of rhythmic accuracy of keystrokes. Strong temporal constraints on finger movements during piano playing may underlie the maintained independent control of fingers over a wider range of tempi, a feature being likely to be specific to skilled pianists. PMID:22815403

Open dislocation of the proximal interphalangeal joint of the little finger subsequent to chronic radial collateral ligament injury: a case report of primary ligament reconstruction with a half-slip of the flexor digitorum superficialis: Case Report.

PubMed

Wada, Kazuma; Hibino, Naohito; Kondo, Kenji; Yoshioka, Shinji; Terai, Tomoya; Henmi, Tatsuhiko; Sairyo, Koichi

2015-01-01

Open dislocation of the proximal interphalangeal (PIP) joint is relatively rare. We report a case of a 32-year-old man who had open dislocation of the PIP joint of the little finger while playing American football. He had a history of chronic radial collateral ligament injury. We reconstructed the radial collateral ligament with a half-slip of the flexor digitorum superficialis tendon.

Associations of work activities requiring pinch or hand grip or exposure to hand-arm vibration with finger and wrist osteoarthritis: a meta-analysis.

PubMed

Hammer, Paula E C; Shiri, Rahman; Kryger, Ann I; Kirkeskov, Lilli; Bonde, Jens Peter

2014-03-01

We systematically reviewed the epidemiologic evidence linking finger and wrist osteoarthritis (OA) with work activities requiring pinch or hand grip or exposure to hand-arm vibration (HAV). PubMed and Embase databases were searched up to June 2013. We selected studies assessing the associations of radiographic diagnosed finger and/or wrist joint OA with work activities involving pinch or hand grip or exposure to HAV. We used specific criteria to evaluate completeness of reporting, potential confounding, and bias. Pooled odds ratios (OR) were computed using random-effects meta-analyses. Of the 19 studies included, 17 were cross-sectional, 1 was a prospective cohort, and 1 a case-control study. The meta-analyses of studies that controlled their estimates for at least age and gender showed the associations of pinch grip work with proximal interphalangeal joint [OR 1.56, 95% confidence interval (95% CI) 1.09-2.23] and the first carpometacarpal joint OA (OR 2.10, 95% CI 1.06-4.17), but not with distal interphalangeal, metacarpalphalangeal, or wrist joints OA. Hand grip work and exposure to HAV were not associated with any finger or wrist OA. Epidemiological studies provide limited evidence that pinch grip may increase the risk of wrist or finger OA, but causal relation cannot be resolved because of cross-sectional designs and inadequate characterization of biomechanical strain to the hand and wrist.

[Treatment of fractures of proximal phalanx of fingers by Eiffel Tower percutaneous pinning method. A review of 45 cases].

PubMed

Chbani, B; Amar, M F; Loudyi, D; Boutayeb, F

2010-04-01

The authors report in the treatment of fractures of the proximal phalanx of the fingers, the use of Eiffel Tower pinning, a relatively simple method, fast and stable, associated to a protection and early rehabilitation. The objective of this method is to offer to the patient a pollici-digital grip. Our study is a retrospective study of 45 patients treated for fractures of the proximal phalanx of the fingers by percutaneous pinning according to Eiffel Tower method. We detail this simple and economic technique and examine the functional and radiological results of this series of patients. The amplitude of the active total motion of the proximal interphalangeal joint is on average 94.16 degrees (78.5 % of the normal active mobility of the proximal interphalangeal joint), and the amplitude of the active total motion of the metacarpo-phalangeal joint is on average 90.05 degrees (75 % of the normal active mobility of the metacarpo-phalangeal joint). Copyright 2010 Elsevier Masson SAS. All rights reserved.

Hybrid Photoacoustic/Ultrasound Tomograph for Real-Time Finger Imaging.

PubMed

Oeri, Milan; Bost, Wolfgang; Sénégond, Nicolas; Tretbar, Steffen; Fournelle, Marc

2017-10-01

We report a target-enclosing, hybrid tomograph with a total of 768 elements based on capacitive micromachined ultrasound transducer technology and providing fast, high-resolution 2-D/3-D photoacoustic and ultrasound tomography tailored to finger imaging. A freely programmable ultrasound beamforming platform sampling data at 80 MHz was developed to realize plane wave transmission under multiple angles. A multiplexing unit enables the connection and control of a large number of elements. Fast image reconstruction is provided by GPU processing. The tomograph is composed of four independent and fully automated movable arc-shaped transducers, allowing imaging of all three finger joints. The system benefits from photoacoustics, yielding high optical contrast and enabling visualization of finger vascularization, and ultrasound provides morphologic information on joints and surrounding tissue. A diode-pumped, Q-switched Nd:YAG laser and an optical parametric oscillator are used to broaden the spectrum of emitted wavelengths to provide multispectral imaging. Custom-made optical fiber bundles enable illumination of the region of interest in the plane of acoustic detection. Precision in positioning of the probe in motion is ensured by use of a motor-driven guide slide. The current position of the probe is encoded by the stage and used to relate ultrasound and photoacoustic signals to the corresponding region of interest of the suspicious finger joint. The system is characterized in phantoms and a healthy human finger in vivo. The results obtained promise to provide new opportunities in finger diagnostics and establish photoacoustic/ultrasound-tomography in medical routine. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Segmentation of hand radiographs using fast marching methods

NASA Astrophysics Data System (ADS)

Chen, Hong; Novak, Carol L.

2006-03-01

Rheumatoid Arthritis is one of the most common chronic diseases. Joint space width in hand radiographs is evaluated to assess joint damage in order to monitor progression of disease and response to treatment. Manual measurement of joint space width is time-consuming and highly prone to inter- and intra-observer variation. We propose a method for automatic extraction of finger bone boundaries using fast marching methods for quantitative evaluation of joint space width. The proposed algorithm includes two stages: location of hand joints followed by extraction of bone boundaries. By setting the propagation speed of the wave front as a function of image intensity values, the fast marching algorithm extracts the skeleton of the hands, in which each branch corresponds to a finger. The finger joint locations are then determined by using the image gradients along the skeletal branches. In order to extract bone boundaries at joints, the gradient magnitudes are utilized for setting the propagation speed, and the gradient phases are used for discriminating the boundaries of adjacent bones. The bone boundaries are detected by searching for the fastest paths from one side of each joint to the other side. Finally, joint space width is computed based on the extracted upper and lower bone boundaries. The algorithm was evaluated on a test set of 8 two-hand radiographs, including images from healthy patients and from patients suffering from arthritis, gout and psoriasis. Using our method, 97% of 208 joints were accurately located and 89% of 416 bone boundaries were correctly extracted.

The compensatory motion of wrist immobilization on thumb and index finger performance--kinematic analysis and clinical implications.

PubMed

Liu, Chien-Hsiou; Chiang, Hsin-Yu; Chen, Kun-Hung

2015-01-01

Based on the high prevalence of people with problems in the wrist and hand simultaneously, it is of its importance to clarify whether hand joints exert extra motion to compensate for wrist motion while immobilized. This study aimed to measure the compensatory movement of the thumb and index finger when people perform daily activities with an immobilized wrist. Thirty healthy volunteers were recruited in this study. A wrist splint, the Jebsen-Taylor Hand Function Test, and the OptoTrak Certus motion tracking system were used. Seven inter-digit mean joint angles of the index finger and thumb were calculated. Paired sample t-test was used. (1) The compensatory motions were noted in the Metacarpophalangeal and Carpometacarpal joints of the thumb, and the proximal interphalangeal joints of the index finger; (2) The manifestation of compensatory motion was related to type of activity performed except when picking up light and heavy cans. The compensatory motions appeared while the wrist was immobilized and were found to be disadvantageous to the progression of disease. In the future, studies need to be done to understand how to select products with correct ergonomic design to enable people to reap greater benefits from wearing wrist splints.

Jam Injuries of the Finger: Diagnosis and Management of Injuries to the Interphalangeal Joints Across Multiple Sports and Levels of Experience.

PubMed

Carruthers, Katherine H; Skie, Martin; Jain, Margaret

2016-09-01

Jam injuries of the finger are frequently encountered in general orthopaedic and sports medicine practice. The finger joints in particular are very susceptible to traumatic injury, but in the absence of severe deformity, digital trauma is often downplayed in the hopes of a more rapid return to game play. Articles published from 1966 to 2015 were reviewed to capture historical and current views on the presentation, diagnosis, and treatment of jam injuries in athletes. Clinical review. Level 5. Although jam injuries are frequently grouped together, they represent a host of injuries that can be challenging to differentiate. A thorough knowledge of finger joint anatomy and injury mechanism is critical to perform an appropriate examination, establish an accurate diagnosis, and identify a treatment plan for each patient. Every member of the athletic care team must be aware of the spectrum of digital injuries, including the basic signs present on examination, which may indicate the need for more formal workup. Additionally, preventing injury through athlete education is paramount to athletic care. © 2016 The Author(s).

Successful treatment of a guitarist with a finger joint injury using instrument-assisted soft tissue mobilization: a case report

PubMed Central

Terry Loghmani, M.; Bayliss, Amy J.; Clayton, Greg; Gundeck, Evelina

2015-01-01

Finger injuries are common and can greatly affect a musician’s quality of life. A 55-year-old man, who had injured the proximal interphalangeal joint of the left index finger 6 months prior to any intervention, was treated with a manual therapy approach incorporating instrument-assisted soft tissue mobilization (IASTM). Initial examination findings included self-reported pain and functional limitations and physical impairments that significantly impeded his ability to play the acoustic guitar. He was treated once a week for 6 weeks with IASTM, joint mobilization, therapeutic exercise, and ice massage. Additionally, a home exercise program and self-care instructions were provided. The patient gained positive outcomes with improvements in pain (Numerical Pain Rating Scale while playing the guitar: initial 5/10, discharge 1/10) and function (Disability Arm Shoulder Hand Sports-Performing Arts Optional Module: initial 75; discharge 6·25), each reaching a minimum clinically important difference. Importantly, he was able to play the guitar with minimal to no pain as desired. Physical measures also improved, including an immediate gain in finger range of motion with IASTM alone. Manual therapy approaches integrating IASTM may provide an effective conservative treatment strategy for patients with finger/hand conditions in the performing arts and other patient populations. PMID:26952165

iHandRehab: an interactive hand exoskeleton for active and passive rehabilitation.

PubMed

Li, Jiting; Zheng, Ruoyin; Zhang, Yuru; Yao, Jianchu

2011-01-01

This paper presents an interactive exoskeleton device for hand rehabilitation, iHandRehab, which aims to satisfy the essential requirements for both active and passive rehabilitation motions. iHandRehab is comprised of exoskeletons for the thumb and index finger. These exoskeletons are driven by distant actuation modules through a cable/sheath transmission mechanism. The exoskeleton for each finger has 4 degrees of freedom (DOF), providing independent control for all finger joints. The joint motion is accomplished by a parallelogram mechanism so that the joints of the device and their corresponding finger joints have the same angular displacement when they rotate. Thanks to this design, the joint angles can be measured by sensors real time and high level motion control is therefore made very simple without the need of complicated kinematics. The paper also discusses important issues when the device is used by different patients, including its adjustable joint range of motion (ROM) and adjustable range of phalanx length (ROPL). Experimentally collected data show that the achieved ROM is close to that of a healthy hand and the ROPL covers the size of a typical hand, satisfying the size need of regular hand rehabilitation. In order to evaluate the performance when it works as a haptic device in active mode, the equivalent moment of inertia (MOI) of the device is calculated. The results prove that the device has low inertia which is critical in order to obtain good backdrivability. Experimental analysis shows that the influence of friction accounts for a large portion of the driving torque and warrants future investigation. © 2011 IEEE

Prevalence of self-reported finger deformations and occupational risk factors among professional cooks: a cross-sectional study.

PubMed

Nagasu, Miwako; Sakai, Kazuhiro; Kogi, Kazutaka; Ito, Akiyoshi; Feskens, Edith J M; Tomita, Shigeru; Temmyo, Yoshiomi; Ueno, Mitsuo; Miyagi, Shigeji

2011-05-26

Previous studies have pointed out that the school lunch workers in Japan are suffering from work-related disorders including finger deformations. The purpose of this study was to investigate the prevalence of self-reported finger deformations and the association with job-related risk factors. A cross-sectional questionnaire study of 5,719 subjects (response rate: 81%, 982 men and 4,737 women) was undertaken during September 2003 to February 2004. Finger deformations were found among 11.7% of the men and 35.6% of the women studied, with significant differences among sex, age and sex-age groups. For both men and women the pattern of finger deformations across the hand was similar for the right and the left hand. For women, the deformations were found in about 10% of the distal interphalangeal joints of all fingers. Based on multiple logistic regression analyses, the factors female sex, age, the number of cooked lunches per cook and cooking activities were independently associated with the prevalence of finger deformations. High prevalence odds ratios were found for those frequently carrying or using tools by hands such as delivering containers, distributing meals, preparing dishes, washing equipment, cutting and stirring foods. Among the school lunch workers studied, women had a higher prevalence of finger deformations on all joints of both hands. Various cooking tasks were associated with the prevalence of finger deformations. The results suggest that improvements in working conditions are important for preventing work-related disorders such as finger deformations.

Photoacoustic tomography of the human finger: towards the assessment of inflammatory joint diseases

NASA Astrophysics Data System (ADS)

van Es, P.; Biswas, S. K.; Bernelot Moens, H. J.; Steenbergen, W.; Manohar, S.

2015-03-01

Inflammatory arthritis is often manifested in finger joints. The growth of new or withdrawal of old blood vessels can be a sensitive marker for these diseases. Photoacoustic (PA) imaging has great potential in this respect since it allows the sensitive and highly resolved visualization of blood. We systematically investigated PA imaging of finger vasculature in healthy volunteers using a newly developed PA tomographic system. We present the PA results which show excellent detail of the vasculature. Vessels with diameters ranging between 100 μm and 1.5 mm are visible along with details of the skin, including the epidermis and the subpapillary plexus. The focus of all the studies is at the proximal and distal interphalangeal joints, and in the context of ultimately visualizing the inflamed synovial membrane in patients. This work is important in laying the foundation for detailed research into PA imaging of the phalangeal vasculature in patients suffering from rheumatoid arthritis.

High resolution three-dimensional photoacoustic imaging of human finger joints in vivo

NASA Astrophysics Data System (ADS)

Xi, Lei; Jiang, Huabei

2015-08-01

We present a method for noninvasively imaging the hand joints using a three-dimensional (3D) photoacoustic imaging (PAI) system. This 3D PAI system utilizes cylindrical scanning in data collection and virtual-detector concept in image reconstruction. The maximum lateral and axial resolutions of the PAI system are 70 μm and 240 μm. The cross-sectional photoacoustic images of a healthy joint clearly exhibited major internal structures including phalanx and tendons, which are not available from the current photoacoustic imaging methods. The in vivo PAI results obtained are comparable with the corresponding 3.0 T MRI images of the finger joint. This study suggests that the proposed method has the potential to be used in early detection of joint diseases such as osteoarthritis.

MR imaging of the metacarpophalangeal joints of the fingers: evaluation of 38 patients with chronic joint disability.

PubMed

Theumann, Nicolas H; Pessis, Eric; Lecompte, Martin; Le Viet, Dominique; Valenti, Philippe; Chevrot, Alain; Bittoun, Jacques; Schnyder, Pierre; Resnick, Donald; Drapé, Jean-Luc

2005-04-01

To report the MR imaging findings of painful injured metacarpophalangeal (MCP) joints of the fingers. MR imaging of 39 injured MCP joints in 38 patients was performed after a mean delay of 8.8 months. The MR images were obtained with the fingers in extended and flexed positions using T2-weighted and T1-weighted sequences before and after intravenous injection of a gadolinium compound. Ten patients were treated surgically. Mean clinical follow-up was 1.8 years. Tears of the collateral ligaments were the most common lesion (30/39), most being radial in location. Contrast-enhanced axial T1-weighted images with the MCP joint in a flexed position showed these lesions optimally. Ten tears were partial and 20 were complete. In 13 patients, MR images showed 17 associated lesions including injuries of the extensor hood (10/17), interosseous tendon (3/17), palmar plate (3/17), and an osteochondral lesion (1/17). Sagittal MR images were essential to highlight palmar plate tears. Partial or complete tears of the collateral ligaments are prevalent MR imaging findings in patients with chronic disability resulting from injuries to the MCP joints. Although conservative treatment generally is sufficient for isolated injuries of the collateral ligaments, surgical repair is often required in cases of more extensive injuries. MR imaging may clearly delineate associated lesions of and about the MCP joints.

Customizing Extensor Reconstruction in Vascularized Toe Joint Transfers to Finger Proximal Interphalangeal Joints: A Strategic Approach for Correcting Extensor Lag.

PubMed

Loh, Charles Yuen Yung; Hsu, Chung-Chen; Lin, Cheng-Hung; Chen, Shih-Heng; Lien, Shwu-Huei; Lin, Chih-Hung; Wei, Fu-Chan; Lin, Yu-Te

2017-04-01

Vascularized toe proximal interphalangeal joint transfer allows the restoration of damaged joints. However, extensor lag and poor arc of motion have been reported. The authors present their outcomes of treatment according to a novel reconstructive algorithm that addresses extensor lag and allows for consistent results postoperatively. Vascularized toe joint transfers were performed in a consecutive series of 26 digits in 25 patients. The average age was 30.5 years, with 14 right and 12 left hands. Reconstructed digits included eight index, 10 middle, and eight ring fingers. Simultaneous extensor reconstructions were performed and eight were centralization of lateral bands, five were direct extensor digitorum longus-to-extensor digitorum communis repairs, and 13 were central slip reconstructions. The average length of follow-up was 16.7 months. The average extension lag was 17.9 degrees. The arc of motion was 57.7 degrees (81.7 percent functional use of pretransfer toe proximal interphalangeal joint arc of motion). There was no significant difference in the reconstructed proximal interphalangeal joint arc of motion for the handedness (p = 0.23), recipient digits (p = 0.37), or surgical experience in vascularized toe joint transfer (p = 0.25). The outcomes of different techniques of extensor mechanism reconstruction were similar in terms of extensor lag, arc of motion, and reconstructed finger arc of motion compared with the pretransfer toe proximal interphalangeal joint arc of motion. With this treatment algorithm, consistent outcomes can be produced with minimal extensor lag and maximum use of potential toe proximal interphalangeal joint arc of motion. Therapeutic, IV.

Kinematic performance of a six degree-of-freedom hand model (6DHand) for use in occupational biomechanics.

PubMed

Buczek, Frank L; Sinsel, Erik W; Gloekler, Daniel S; Wimer, Bryan M; Warren, Christopher M; Wu, John Z

2011-06-03

Upper extremity musculoskeletal disorders represent an important health issue across all industry sectors; as such, the need exists to develop models of the hand that provide comprehensive biomechanics during occupational tasks. Previous optical motion capture studies used a single marker on the dorsal aspect of finger joints, allowing calculation of one and two degree-of-freedom (DOF) joint angles; additional algorithms were needed to define joint centers and the palmar surface of fingers. We developed a 6DOF model (6DHand) to obtain unconstrained kinematics of finger segments, modeled as frusta of right circular cones that approximate the palmar surface. To evaluate kinematic performance, twenty subjects gripped a cylindrical handle as a surrogate for a powered hand tool. We hypothesized that accessory motions (metacarpophalangeal pronation/supination; proximal and distal interphalangeal radial/ulnar deviation and pronation/supination; all joint translations) would be small (less than 5° rotations, less than 2mm translations) if segment anatomical reference frames were aligned correctly, and skin movement artifacts were negligible. For the gripping task, 93 of 112 accessory motions were small by our definition, suggesting this 6DOF approach appropriately models joints of the fingers. Metacarpophalangeal supination was larger than expected (approximately 10°), and may be adjusted through local reference frame optimization procedures previously developed for knee kinematics in gait analysis. Proximal translations at the metacarpophalangeal joints (approximately 10mm) were explained by skin movement across the metacarpals, but would not corrupt inverse dynamics calculated for the phalanges. We assessed performance in this study; a more rigorous validation would likely require medical imaging. Published by Elsevier Ltd.

[Treatment of bacterial infection in the interphalangeal joints of the hand].

PubMed

Vorderwinkler, K-P; Mühldorfer, M; Pillukat, T; van Schoonhoven, J

2011-07-01

Radical debridement of joint infection, prevention of further infection-related tissue destruction. Septic arthritis of interphalangeal joints in the thumb and fingers. Extensive soft tissue defects. Severe impairment of blood circulation, finger gangrene. Noncompliance for immobilization or for treatment with external fixator. Arthrotomy and irrigation with isotonic solution. Radical tissue debridement. Joint preservation possible only in the absence of infection-related macroscopic cartilage damage. Otherwise, resection of the articular surfaces and secondary arthrodesis. Insertion of antibiotic-coated devices. Temporary immobilization with external fixator. Inpatient postoperative treatment with 5-day intravenous administration of a second-generation cephalosporine (e.g., Cefuroxim®) followed by 7-10 days oral application. Adaptation of antibiotics according to antibiogram results. In joint-preserving procedures, radiographs and fixator removal after 4 weeks, active joint mobilization. If joint surfaces were resected, removal of fixator after 6 weeks; arthrodesis under 3-day intravenous broad-band antibiotic prophylaxis. Splint immobilization until consolidation (6-8 weeks). In 10 of 40 patients, the infected joint could be preserved. All infections healed. After an average duration of therapy of 6 (3-11) weeks, 4 individuals were free of complaints, and 6 patients had minor symptoms. Overall range of motion in the affected finger was reduced by 25-50° in 5 patients. All patients could return to work after 6.6 (4-11) weeks. A total of 30 patients were treated with joint resection and external fixator. After 5.6 (4-8) weeks, arthrodesis was performed, leading to consolidation in 29 patients. One patient underwent amputation after 4 months due to delayed gangrene. Treatment duration was 15.7 (7-25) weeks. Eight patients reported no complaints, 14 suffered mild symptoms, 5 had moderate, and 3 had severe symptoms in daily life. In 15 cases, range of motion was diminished by 10-80° in the remaining joints of the affected finger. Patients could return to work after 16.2 (6-28) weeks.

Estimation of Saxophone Control Parameters by Convex Optimization.

PubMed

Wang, Cheng-I; Smyth, Tamara; Lipton, Zachary C

2014-12-01

In this work, an approach to jointly estimating the tone hole configuration (fingering) and reed model parameters of a saxophone is presented. The problem isn't one of merely estimating pitch as one applied fingering can be used to produce several different pitches by bugling or overblowing. Nor can a fingering be estimated solely by the spectral envelope of the produced sound (as it might for estimation of vocal tract shape in speech) since one fingering can produce markedly different spectral envelopes depending on the player's embouchure and control of the reed. The problem is therefore addressed by jointly estimating both the reed (source) parameters and the fingering (filter) of a saxophone model using convex optimization and 1) a bank of filter frequency responses derived from measurement of the saxophone configured with all possible fingerings and 2) sample recordings of notes produced using all possible fingerings, played with different overblowing, dynamics and timbre. The saxophone model couples one of several possible frequency response pairs (corresponding to the applied fingering), and a quasi-static reed model generating input pressure at the mouthpiece, with control parameters being blowing pressure and reed stiffness. Applied fingering and reed parameters are estimated for a given recording by formalizing a minimization problem, where the cost function is the error between the recording and the synthesized sound produced by the model having incremental parameter values for blowing pressure and reed stiffness. The minimization problem is nonlinear and not differentiable and is made solvable using convex optimization. The performance of the fingering identification is evaluated with better accuracy than previous reported value.

Smart material joint band

NASA Astrophysics Data System (ADS)

Tucchio, Michael A.; Stoodt, Robert A.; Livsey, Robert A.

1994-11-01

The present invention relates to an improved connector for joining two tubular members together. The connector is formed by a plurality of longitudinally extending fingers extending from an end of one of tubular members and at least one locking groove in the other of the tubular members for receiving the fingers. The connector further includes a circumferentially extending wire member which is received in a notch in a head portion of each of the plurality of fingers. The wire member is preferably formed from a shape memory alloy and has an original circumference less than the circumference of a circle formed by the notches in a head portions of the fingers. The connector includes apertures through which electric wires may be connected to the shape memory alloy ring member so as to cause the shape memory alloy ring member to return to its original shape and allow release of the joint connection.

Smart material joint band

NASA Astrophysics Data System (ADS)

Tucchio, Michael A.; Stoodt, Robert A.; Livsey, Robert A.

1993-12-01

The present invention relates to an improved connector for joining two tubular members together. The connector is formed by a plurality of longitudinally extending fingers extending from an end of one of the tubular members and at least one locking groove in the other of the tubular members for receiving the fingers. The connector further includes a circumferentially extending wire member which is received in a notch in a head portion of each of the plurality of fingers. The wire member is preferably formed from a shape memory alloy and has an original circumference less than the circumference of a circle formed by the notches in the head portions of the fingers. The connector includes apertures through which electric wires may be connected to the shape memory alloy ring member so as to cause the shape memory alloy ring member to return to its original shape and allow release of the joint connection.

The Power of a Soccer Ball: A Traumatic Open Finger Dislocation-A Rare Case Presentation.

PubMed

Dülgeroğlu, Turan Cihan; Metineren, Hasan; Aydın, Ekrem; Dülgeroğlu, Ayşegül

2015-01-01

Proximal interphalangeal joint dislocations are injuries observed frequently and caused by axial loading on the finger in the extension. In this paper we present a traumatic open finger dislocation due to a ball hitting a wrestler. It was successfully treated with reduction and the volar plate and collateral bond fixation were applied with absorbable sutures.

Man-equivalent telepresence through four fingered human-like hand system

NASA Technical Reports Server (NTRS)

Jau, Bruno M.

1992-01-01

The author describes a newly developed mechanical hand system. The robot hand is in human-like configuration with a thumb and three fingers, a palm, a wrist, and the forearm in which the hand and wrist actuators are located. Each finger and the wrist has its own active electromechanical compliance system, allowing the joint drive trains to be stiffened or loosened. This mechanism imitates the human muscle dual function of positioner and stiffness controller. This is essential for soft grappling operations. The hand-wrist assembly has 16 finger joints, three wrist joints, and five compliance mechanisms for a total of 24 degrees of freedom. The strength of the hand is roughly half that of the human hand and its size is comparable to a male hand. The hand is controlled through an exoskeleton glove controller that the operator wears. The glove provides the man-machine interface in telemanipulation control mode: it senses the operator's inputs to guide the mechanical hand in hybrid position and force control. The hand system is intended for dexterous manipulations in structured environments. Typical applications will include work in hostile environment such as space operations and nuclear power plants.

Computer-aided classification of optical images for diagnosis of osteoarthritis in the finger joints.

PubMed

Zhang, Jiang; Wang, James Z; Yuan, Zhen; Sobel, Eric S; Jiang, Huabei

2011-01-01

This study presents a computer-aided classification method to distinguish osteoarthritis finger joints from healthy ones based on the functional images captured by x-ray guided diffuse optical tomography. Three imaging features, joint space width, optical absorption, and scattering coefficients, are employed to train a Least Squares Support Vector Machine (LS-SVM) classifier for osteoarthritis classification. The 10-fold validation results show that all osteoarthritis joints are clearly identified and all healthy joints are ruled out by the LS-SVM classifier. The best sensitivity, specificity, and overall accuracy of the classification by experienced technicians based on manual calculation of optical properties and visual examination of optical images are only 85%, 93%, and 90%, respectively. Therefore, our LS-SVM based computer-aided classification is a considerably improved method for osteoarthritis diagnosis.

A Biomechanical Simulation of the Effect of the Extrinsic Flexor Muscles on Finger Joint Flexion

DTIC Science & Technology

2001-10-25

vol. 44, pp. 493-504, 1997. [8] A.B. Leger and T.E. Milner, “The effect of eccentric exercise on intrinsic and reflex stiffness in the human hand...line of action of the tendons and the effective moment arms. After a certain point, the FDP tendon became slack, while the FDS tendon remained...link chain with three revolute joints and four links was created to model the index finger. The tendons from the extrinsic flexor muscles were

On the complexity of classical guitar playing: functional adaptations to task constraints.

PubMed

Heijink, Hank; Meulenbroek, Ruud G J

2002-12-01

The authors performed a behavioral study of the complexity of left-hand finger movements in classical guitar playing. Six professional guitarists played movement sequences in a fixed tempo. Left-hand finger movements were recorded in 3 dimensions, and the guitar sound was recorded synchronously. Assuming that performers prefer to avoid extreme joint angles when moving, the authors hypothesized 3 complexity factors. The results showed differential effects of the complexity factors on the performance measures and on participants' judgments of complexity. The results demonstrated that keeping the joints in the middle of their range is an important principle in guitar playing, and players exploit the available tolerance in timing and placement of the left-hand fingers to control the acoustic output variability.

[Fractures of the proximal interphalangeal joint: Diagnostic and operative therapy options].

PubMed

Unglaub, F; Langer, M F; Hahn, P; Müller, L P; Ahrens, C; Spies, C K

2016-02-01

Joint fractures of the fingers often entail operative interventions in contrast to extra-articular fractures. These types of fracture are inclined to dislocate in addition to the actual fracture. The proximal interphalangeal (PIP) joint in particular often shows comminuted fractures due to the long leverage of the finger and a relatively small diameter of the joint. The clinical examination, X-ray diagnostics and if necessary computed tomography allow the classification into stable and unstable fractures. Unstable fractures must be treated by surgical reduction and fixation. A multitude of operative techniques are available for these mostly complicated fractures. The foremost goal is a stable osteosynthesis of the fracture with repositioning of the dislocation, which enables early physiotherapy in order to prevent tendon adhesion and contracture. This article presents the different types of PIP joint fractures, their specific surgical treatment and postoperative treatment regimens.

Experiments and kinematics analysis of a hand rehabilitation exoskeleton with circuitous joints.

PubMed

Zhang, Fuhai; Fu, Yili; Zhang, Qinchao; Wang, Shuguo

2015-01-01

Aiming at the hand rehabilitation of stroke patients, a wearable hand exoskeleton with circuitous joint is proposed. The circuitous joint adopts the symmetric pinion and rack mechanism (SPRM) with the parallel mechanism. The exoskeleton finger is a serial mechanism composed of three closed-chain SPRM joints in series. The kinematic equations of the open chain of the finger and the closed chains of the SPRM joints were built to analyze the kinematics of the hand rehabilitation exoskeleton. The experimental setup of the hand rehabilitation exoskeleton was built and the continuous passive motion (CPM) rehabilitation experiment and the test of human-robot interaction force measurement were conducted. Experiment results show that the mechanical design of the hand rehabilitation robot is reasonable and that the kinematic analysis is correct, thus the exoskeleton can be used for the hand rehabilitation of stroke patients.

[Plantar fibromatosis and Dupuytren's contracture in an adolescent].

PubMed

Nikolić, Jelena; Janjić, Zlata; Momcilović, Dragan; Ninković, Srdjan; Harhai, Vladimir

2011-10-01

Fibromatosis represents a wide group of benign, locally proliferative disorders of fibroblasts. Dupuytren's disease is a benign proliferative disease of palmar aponeurosis which usually affects adults between 40 and 60 years of age. Ledderhose's disease or plantar fibromatosis is plantar equivalent of Dupuyten's disease most often affecting middle-aged and older men, usually bilateral, represented with painless nodule in the medial division of plantar fascia. We presented a 19-year old adolescent that turned to a plastic surgeon complaining to his small finger contracture. He noticed palmar thickening with nodule over the metacarpophalangeal joint of small finger of his right hand when he was 16 years old. A year later a finger started to band. During physical checkup we noticed plantar nodule that also had his father and grandmother. Magnetic resonance and tumor biopsy confirmed a suspicion on plantar fibromatosis - Ledderhose's disease. Clinical exam of the hand clearly led to a conclusion that the patient had Dupuytren's contracture with pretendinous cord over the small finger flexor tendons and lack of extension of proximal interphalangeal (PIP) joint. On the extensor side of the PIP joints there were Garrod's nodes. The patient refused surgical treatment of plantar tumor, but agreed to surgical correction of finger contracture. Despite the fact that Dupuytren's disease and plantar fibromatosis are diseases of adults, the possibility of conjoint appearance of these forms of fibromatosis in adolescent period of life should be kept in mind especially in patients with strong genetic predisposition.

Lack of Hypertonia in Thumb Muscles After Stroke

PubMed Central

Kamper, Derek G.; Rymer, William Z.

2010-01-01

Despite the importance of the thumb to hand function, little is known about the origins of thumb impairment poststroke. Accordingly, the primary purpose of this study was to assess whether thumb flexors have heightened stretch reflexes (SRs) following stroke-induced hand impairment. The secondary purpose was to compare SR characteristics of thumb flexors in relation to those of finger flexors since it is unclear whether SR properties of both muscle groups are similarly affected poststroke. Stretch reflexes in thumb and finger flexors were assessed at rest on the paretic side in each of 12 individuals with chronic, severe, stroke-induced hand impairment and in the dominant thumb in each of eight control subjects also at rest. Muscle activity and passive joint flexion torques were measured during imposed slow (SS) and fast stretches (FS) of the flexors that span the metacarpophalangeal joints. Putative spasticity was then quantified in terms of the peak difference between FS and SS joint torques and electromyographic changes. For both the hemiparetic and control groups, the mean normalized peak torque differences (PTDs) measured in thumb flexors were statistically indistinguishable (P = 0.57). In both groups, flexor muscles were primarily unresponsive to rapid stretching. For 10 of 12 hemiparetic subjects, PTDs in thumb flexors were less than those in finger flexors (P = 0.03). Paretic finger flexor muscle reflex activity was consistently elicited during rapid stretching. These results may reflect an important difference between thumb and finger flexors relating to properties of the involved muscle afferents and spinal motoneurons. PMID:20668270

The 3-D vision system integrated dexterous hand

NASA Technical Reports Server (NTRS)

Luo, Ren C.; Han, Youn-Sik

1989-01-01

Most multifingered hands use a tendon mechanism to minimize the size and weight of the hand. Such tendon mechanisms suffer from the problems of striction and friction of the tendons resulting in a reduction of control accuracy. A design for a 3-D vision system integrated dexterous hand with motor control is described which overcomes these problems. The proposed hand is composed of three three-jointed grasping fingers with tactile sensors on their tips, a two-jointed eye finger with a cross-shaped laser beam emitting diode in its distal part. The two non-grasping fingers allow 3-D vision capability and can rotate around the hand to see and measure the sides of grasped objects and the task environment. An algorithm that determines the range and local orientation of the contact surface using a cross-shaped laser beam is introduced along with some potential applications. An efficient method for finger force calculation is presented which uses the measured contact surface normals of an object.

Design and control of a hand exoskeleton for use in extravehicular activities

NASA Technical Reports Server (NTRS)

Shields, B.; Peterson, S.; Strauss, A.; Main, J.

1993-01-01

To counter problems inherent in extravehicular activities (EVA) and complex space operations, an exoskeleton, a unique adaptive structure, has been designed. The exoskeleton fits on the hand and powers the proximal and middle phalanges of the index finger, the middle finger, and the combined ring and little finger. A kinematic analysis of the exoskeleton joints was performed using the loop-closure method. This analysis determined the angular displacement and velocity relationships of the exoskeleton joints. This information was used to determine the output power of the exoskeleton. Three small DC motors (one for each finger) are used to power the exoskeleton. The motors are mounted on the forearm. Power is transferred to the exoskeleton using lead screws. The control system for the exoskeleton measures the contact force between the operator and the exoskeleton. This information is used as the input to drive the actuation system. The control system allows the motor to rotate in both directions so that the operator may close or open the exoskeleton.

[Microcirculatory investigations in hemophilia patients].

PubMed

Davydkin, I L; Kosiakova, Iu A

2012-01-01

to evaluate microcirculation (MC) and its influencing factors in hemophilia patients. In 44 hemophilia patients with recurrent hemarthrosis, laser Doppler flowmetry was used to evaluate resting MC above the index fingers, knee and ankle joints during an occlusion test, with allowance made for muscle and adipose tissue mass. The increased perfusion value above the afflicted joints was found to correspond to the phase of an exacerbation of posthemorrhagic inflammation and to be a risk factor of recurrent hemarrthrosis. Analysis of the occlusion test above the knee joints and index fingers revealed a diminished MC reserve and a tendency to precapillary spasm. MC changes were more pronounced in a shortage of muscle and adipose tissue mass. Hemophilia patients must regularly do physical exercises to make skeletal muscles develop well in order to prevent an exacerbation of the joint inflammatory process.

Tomosynthesis can facilitate accurate measurement of joint space width under the condition of the oblique incidence of X-rays in patients with rheumatoid arthritis.

PubMed

Ono, Yohei; Kashihara, Rina; Yasojima, Nobutoshi; Kasahara, Hideki; Shimizu, Yuka; Tamura, Kenichi; Tsutsumi, Kaori; Sutherland, Kenneth; Koike, Takao; Kamishima, Tamotsu

2016-06-01

Accurate evaluation of joint space width (JSW) is important in the assessment of rheumatoid arthritis (RA). In clinical radiography of bilateral hands, the oblique incidence of X-rays is unavoidable, which may cause perceptional or measurement error of JSW. The objective of this study was to examine whether tomosynthesis, a recently developed modality, can facilitate a more accurate evaluation of JSW than radiography under the condition of oblique incidence of X-rays. We investigated quantitative errors derived from the oblique incidence of X-rays by imaging phantoms simulating various finger joint spaces using radiographs and tomosynthesis images. We then compared the qualitative results of the modified total Sharp score of a total of 320 joints from 20 patients with RA between these modalities. A quantitative error was prominent when the location of the phantom was shifted along the JSW direction. Modified total Sharp scores of tomosynthesis images were significantly higher than those of radiography, that is to say JSW was regarded as narrower in tomosynthesis than in radiography when finger joints were located where the oblique incidence of X-rays is expected in the JSW direction. Tomosynthesis can facilitate accurate evaluation of JSW in finger joints of patients with RA, even with oblique incidence of X-rays. Accurate evaluation of JSW is necessary for the management of patients with RA. Through phantom and clinical studies, we demonstrate that tomosynthesis may achieve more accurate evaluation of JSW.

Concept for a large master/slave-controlled robotic hand

NASA Technical Reports Server (NTRS)

Grissom, William A.; Abdallah, Mahmoud A.; White, Carl L.

1988-01-01

A strategy is presented for the design and construction of a large master/slave-controlled, five-finger robotic hand. Each of the five fingers will possess four independent axes each driven by a brushless DC servomotor and, thus, four degrees-of-freedom. It is proposed that commercially available components be utilized as much as possible to fabricate a working laboratory model of the device with an anticipated overall length of two-to-four feet (0.6 to 1.2 m). The fingers are to be designed so that proximity, tactile, or force/torque sensors can be imbedded in their structure. In order to provide for the simultaneous control of the twenty independent hand joints, a multilevel master/slave control strategy is proposed in which the operator wears a specially instrumented glove which produces control signals corresponding to the finger configurations and which is capable of conveying sensor feedback signals to the operator. Two dexterous hand master devices are currently commercially available for this application with both undergoing continuing development. A third approach to be investigated for the master control mode is the use of real-time image processing of a specially patterned master glove to provide the respective control signals for positioning the multiple finger joints.

The Dorsal 4-finger Technique: A Novel Method to Examine Metacarpophalangeal Joints in Patients with Rheumatoid Arthritis.

PubMed

Omair, Mohammed A; Akhavan, Pooneh; Naraghi, Ali; Mittoo, Shikha; Xiong, Juan; Weber, Deborah; Lin, Daming; Weber, Melissa; Keystone, Edward C

2018-03-01

To describe the dorsal 4-finger technique (DFFT) in examining metacarpophalangeal (MCP) joints of patients with rheumatoid arthritis (RA) and compare it to the traditional 2-finger technique (TFT) using ultrasound (US) as a gold standard. Four rheumatologists evaluated 180 MCP joints of 18 patients with RA. All patients underwent US for greyscale (GSUS) and power Doppler US (PDUS). Agreements between rheumatologists, the 2 techniques, and US were evaluated using Cohen κ and the first-order agreement coefficient (AC1) κ methods. The population comprised 17 females (94.4%) with a mean (SD) age and disease duration of 56.8 (14.4) and 21.8 (12.9) years, respectively. Eight patients (44.4%) were taking methotrexate monotherapy, while 10 patients (55.6%) were receiving biologics. US evaluation revealed 69 (38.3%) and 30 (16.7%) joints exhibited synovitis grade 2-3 by GSUS and PDUS, respectively. Effusion was documented in 30 joints (16.7%). The mean intraobserver agreement using the DFFT and TFT were 80.5% and 86%, respectively. The mean interobserver agreements using the DFFT and TFT were 84% and 74%, respectively. κ agreement with US findings was similar for both techniques in tender joints but was higher for the DFFT in nontender joints (0.33 vs 0.07, p = 0.015 for GSUS) and (0.48 vs 0.11, p = 0.002 for PDUS). The DFFT had a higher sensitivity in detecting ballottement by GSUS (0.47 vs 0.2, p < 0.001) and PDUS (0.60 vs 0.27, p < 0.001). The DFFT is a novel, reproducible, and reliable method to examine MCP joints, and it has a better correlation with US than the traditional TFT.

Sliding Window-Based Region of Interest Extraction for Finger Vein Images

PubMed Central

Yang, Lu; Yang, Gongping; Yin, Yilong; Xiao, Rongyang

2013-01-01

Region of Interest (ROI) extraction is a crucial step in an automatic finger vein recognition system. The aim of ROI extraction is to decide which part of the image is suitable for finger vein feature extraction. This paper proposes a finger vein ROI extraction method which is robust to finger displacement and rotation. First, we determine the middle line of the finger, which will be used to correct the image skew. Then, a sliding window is used to detect the phalangeal joints and further to ascertain the height of ROI. Last, for the corrective image with certain height, we will obtain the ROI by using the internal tangents of finger edges as the left and right boundary. The experimental results show that the proposed method can extract ROI more accurately and effectively compared with other methods, and thus improve the performance of finger vein identification system. Besides, to acquire the high quality finger vein image during the capture process, we propose eight criteria for finger vein capture from different aspects and these criteria should be helpful to some extent for finger vein capture. PMID:23507824

Energy harvesting from mouse click of robot finger using piezoelectrics

NASA Astrophysics Data System (ADS)

Cha, Youngsu; Hong, Jin; Lee, Jaemin; Park, Jung-Min; Kim, Keehoon

2017-04-01

In this paper, we investigate the feasibility of energy harvesting from the mouse click motion using a piezoelectric energy transducer. Specifically, we use a robotic finger to realize repeatable mouse click motion. The robotic finger wears a glove with a pocket for including the piezoelectric material as an energy transducer. We propose a model for the energy harvesting system through the inverse kinematic framework of parallel joints in the finger and the electromechanical coupling equations of the piezoelectric material. Experiments are performed to elucidate the effect of the load resistance and the mouse click motion on energy harvesting.

Probability of spacesuit-induced fingernail trauma is associated with hand circumference.

PubMed

Opperman, Roedolph A; Waldie, James M A; Natapoff, Alan; Newman, Dava J; Jones, Jeffrey A

2010-10-01

A significant number of astronauts sustain hand injuries during extravehicular activity training and operations. These hand injuries have been known to cause fingernail delamination (onycholysis) that requires medical intervention. This study investigated correlations between the anthropometrics of the hand and susceptibility to injury. The analysis explored the hypothesis that crewmembers with a high finger-to-hand size ratio are more likely to experience injuries. A database of 232 crewmembers' injury records and anthropometrics was sourced from NASA Johnson Space Center. No significant effect of finger-to-hand size was found on the probability of injury, but circumference and width of the metacarpophalangeal (MCP) joint were found to be significantly associated with injuries by the Kruskal-Wallis test. A multivariate logistic regression showed that hand circumference is the dominant effect on the likelihood of onycholysis. Male crewmembers with a hand circumference > 22.86 cm (9") have a 19.6% probability of finger injury, but those with hand circumferences < or = 22.86 cm (9") only have a 5.6% chance of injury. Findings were similar for female crewmembers. This increased probability may be due to constriction at large MCP joints by the current NASA Phase VI glove. Constriction may lead to occlusion of vascular flow to the fingers that may increase the chances of onycholysis. Injury rates are lower on gloves such as the superseded series 4000 and the Russian Orlan that provide more volume for the MCP joint. This suggests that we can reduce onycholysis by modifying the design of the current gloves at the MCP joint.

Control of multi-joint arm movements for the manipulation of touch in keystroke by expert pianists

PubMed Central

2010-01-01

Background Production of a variety of finger-key touches in the piano is essential for expressive musical performance. However, it remains unknown how expert pianists control multi-joint finger and arm movements for manipulating the touch. The present study investigated differences in kinematics and kinetics of the upper-limb movements while expert pianists were depressing a key with two different touches: pressed and struck. The former starts key-depression with the finger-tip contacting the key, whereas the latter involves preparatory arm-lift before striking the key. To determine the effect of individual muscular torque (MUS) as well as non-muscular torques on joint acceleration, we performed a series of inverse and forward dynamics computations. Results The pressed touch showed smaller elbow extension velocity, and larger shoulder and finger flexion velocities during key-depression compared with the struck touch. The former touch also showed smaller elbow extension acceleration directly attributed to the shoulder MUS. In contrast, the shoulder flexion acceleration induced by elbow and wrist MUS was greater for the pressed touch than the struck touch. Towards the goal of producing the target finger-key contact dynamics, the pressed and struck touches effectively took advantage of the distal-to-proximal and proximal-to-distal inter-segmental dynamics, respectively. Furthermore, a psychoacoustic experiment confirmed that a tone elicited by the pressed touch was perceived softer than that by the struck touch. Conclusion The present findings suggest that manipulation of tone timbre depends on control of inter-segmental dynamics in piano keystroke. PMID:20630085

Single Degree-of-Freedom Exoskeleton Mechanism Design for Finger Rehabilitation

PubMed Central

Wolbrecht, Eric T.; Reinkensmeyer, David J.; Perez-Gracia, Alba

2014-01-01

This paper presents the kinematic design of a single degree-of-freedom exoskeleton mechanism: a planar eight-bar mechanism for finger curling. The mechanism is part of a finger-thumb robotic device for hand therapy that will allow users to practice key pinch grip and finger-thumb opposition, allowing discrete control inputs for playing notes on a musical gaming interface. This approach uses the mechanism to generate the desired grasping trajectory rather than actuating the joints of the fingers and thumb independently. In addition, the mechanism is confined to the back of the hand, so as to allow sensory input into the palm of the hand, minimal size and apparent inertia, and the possibility of placing multiple mechanisms side-by-side to allow control of individual fingers. PMID:22275628

The Manumeter: A non-obtrusive wearable device for monitoring spontaneous use of the wrist and fingers

PubMed Central

Rowe, Justin B.; Friedman, Nizan; Bachman, Mark; Reinkensmeyer, David J.

2014-01-01

This paper describes the design and pilot testing of a novel device for unobtrusive monitoring of wrist and hand movement through a sensorized watch and a magnetic ring system called the manumeter. The device senses the magnetic field of the ring through two triaxial magnetometers and records the data to onboard memory which can be analyzed later by connecting the watch unit to a computer. Wrist and finger joint angles are estimated using a radial basis function network. We compared joint angle estimates collected using the manumeter to direct measurements taken using a passive exoskeleton and found that after a 60 minute trial, 95% of the radial/ulnar deviation, wrist flexion/extension and finger flexion/extension estimates were within 2.4, 5.8, and 4.7 degrees of their actual values respectively. The device measured angular distance traveled for these three joints within 10.4%, 4.5%, and 14.3 % of their actual values. The manumeter has potential to improve monitoring of real world use of the hand after stroke and in other applications. PMID:24187216

Ball-joint grounding ring

NASA Technical Reports Server (NTRS)

Aperlo, P. J. A.; Buck, P. A.; Weldon, V. A.

1981-01-01

In ball and socket joint where electrical insulator such as polytetrafluoroethylene is used as line to minimize friction, good electrical contact across joint may be needed for lightning protection or to prevent static-charge build-up. Electrical contact is maintained by ring of spring-loaded fingers mounted in socket. It may be useful in industry for cranes, trailers, and other applications requiring ball and socket joint.

Joint Replacement (Finger and Wrist Joints)

MedlinePlus

... Lawnmower Safety Snowblower safety Pumpkin Carving Gardening Safety Turkey Carving Removing a Ring Fireworks Safety Español Artritis ... Lawnmower Safety Snowblower safety Pumpkin Carving Gardening Safety Turkey Carving Removing a Ring Fireworks Safety Español Artritis ...

Applied Joint-Space Torque and Stiffness Control of Tendon-Driven Fingers

NASA Technical Reports Server (NTRS)

Abdallah, Muhammad E.; Platt, Robert, Jr.; Wampler, Charles W.; Hargrave, Brian

2010-01-01

Existing tendon-driven fingers have applied force control through independent tension controllers on each tendon, i.e. in the tendon-space. The coupled kinematics of the tendons, however, cause such controllers to exhibit a transient coupling in their response. This problem can be resolved by alternatively framing the controllers in the joint-space of the manipulator. This work presents a joint-space torque control law that demonstrates both a decoupled and significantly faster response than an equivalent tendon-space formulation. The law also demonstrates greater speed and robustness than comparable PI controllers. In addition, a tension distribution algorithm is presented here to allocate forces from the joints to the tendons. It allocates the tensions so that they satisfy both an upper and lower bound, and it does so without requiring linear programming or open-ended iterations. The control law and tension distribution algorithm are implemented on the robotic hand of Robonaut-2.

Variable and Asymmetric Range of Enslaving: Fingers Can Act Independently over Small Range of Flexion

PubMed Central

van den Noort, Josien C.; van Beek, Nathalie; van der Kraan, Thomas; Veeger, DirkJan H. E. J.; Stegeman, Dick F.; Veltink, Peter H.; Maas, Huub

2016-01-01

The variability in the numerous tasks in which we use our hands is very large. However, independent movement control of individual fingers is limited. To assess the extent of finger independency during full-range finger flexion including all finger joints, we studied enslaving (movement in non-instructed fingers) and range of independent finger movement through the whole finger flexion trajectory in single and multi-finger movement tasks. Thirteen young healthy subjects performed single- and multi-finger movement tasks under two conditions: active flexion through the full range of movement with all fingers free to move and active flexion while the non-instructed finger(s) were restrained. Finger kinematics were measured using inertial sensors (PowerGlove), to assess enslaving and range of independent finger movement. Although all fingers showed enslaving movement to some extent, highest enslaving was found in adjacent fingers. Enslaving effects in ring and little finger were increased with movement of additional, non-adjacent fingers. The middle finger was the only finger affected by restriction in movement of non-instructed fingers. Each finger showed a range of independent movement before the non-instructed fingers started to move, which was largest for the index finger. The start of enslaving was asymmetrical for adjacent fingers. Little finger enslaving movement was affected by multi-finger movement. We conclude that no finger can move independently through the full range of finger flexion, although some degree of full independence is present for smaller movements. This range of independent movement is asymmetric and variable between fingers and between subjects. The presented results provide insight into the role of finger independency for different types of tasks and populations. PMID:27992598

Kinematic Origins of Motor Inconsistency in Expert Pianists.

PubMed

Tominaga, Kenta; Lee, André; Altenmüller, Eckart; Miyazaki, Fumio; Furuya, Shinichi

2016-01-01

For top performers, including athletes and musicians, even subtle inconsistencies in rhythm and force during movement production decrease the quality of performance. However, extensive training over many years beginning in childhood is unable to perfect dexterous motor performance so that it is without any error. To gain insight into the biological mechanisms underlying the subtle defects of motor actions, the present study sought to identify the kinematic origins of inconsistency of dexterous finger movements in musical performance. Seven highly-skilled pianists who have won prizes at international piano competitions played a short sequence of tones with the right hand at a predetermined tempo. Time-varying joint angles of the fingers were recorded using a custom-made data glove, and the timing and velocity of the individual keystrokes were recorded from a digital piano. Both ridge and stepwise multiple regression analyses demonstrated an association of the inter-trial variability of the inter-keystroke interval (i.e., rhythmic inconsistency) with both the rotational velocity of joints of the finger used for a keystroke (i.e., striking finger) and the movement independence between the striking and non-striking fingers. This indicates a relationship between rhythmic inconsistency in musical performance and the dynamic features of movements in not only the striking finger but also the non-striking fingers. In contrast, the inter-trial variability of the key-descending velocity (i.e., loudness inconsistency) was associated mostly with the kinematic features of the striking finger at the moment of the keystroke. Furthermore, there was no correlation between the rhythmic and loudness inconsistencies. The results suggest distinct kinematic origins of inconsistencies in rhythm and loudness in expert musical performance.

Extensor Tendon Injuries and Repairs in the Hand

PubMed Central

Kontor, J. A.

1982-01-01

Due to their superficial course, the extensor tendons are frequently lacerated over the dorsum of the hand and fingers. Excellent functional results are obtained in repairs of simple tendon lacerations. ‘Open’ mallet lacerations over the distal IP joint or involving the central extensor slip over the proximal IP joint require more precise suturing methods. More proximal extensor tendon divisions near the wrist involve dissection of the retracted finger extensors or long thumb extensor in the distal forearm and more formal tendon repairs, including a possible tendon transfer to the thumb. ‘Closed injuries’, with varying degrees of extensor tendon disruption, occur at three main sites. The mallet injury at the DIP joint and the boutonnière deformity over the PIP joint are sometimes recognized late, but respond to conservative splinting for a minimum of four weeks with guarded motion avoiding secondary stiffening of the remaining small joints of the hand. Surgery of closed injuries most frequently involves the intra-articular traction fracture type of mallet deformities in which the DIP joint has taken the brunt of the injury. PMID:21286174

Modelling tendon excursions and moment arms of the finger flexors: anatomic fidelity versus function.

PubMed

Kociolek, Aaron M; Keir, Peter J

2011-07-07

A detailed musculoskeletal model of the human hand is needed to investigate the pathomechanics of tendon disorders and carpal tunnel syndrome. The purpose of this study was to develop a biomechanical model with realistic flexor tendon excursions and moment arms. An existing upper extremity model served as a starting point, which included programmed movement of the index finger. Movement capabilities were added for the other fingers. Metacarpophalangeal articulations were modelled as universal joints to simulate flexion/extension and abduction/adduction while interphalangeal articulations used hinges to represent flexion. Flexor tendon paths were modelled using two approaches. The first method constrained tendons with control points, representing annular pulleys. The second technique used wrap objects at the joints as tendon constraints. Both control point and joint wrap models were iteratively adjusted to coincide with tendon excursions and moment arms from a anthropometric regression model using inputs for a 50th percentile male. Tendon excursions from the joint wrap method best matched the regression model even though anatomic features of the tendon paths were not preserved (absolute differences: mean<0.33 mm, peak<0.74 mm). The joint wrap model also produced similar moment arms to the regression (absolute differences: mean<0.63 mm, peak<1.58 mm). When a scaling algorithm was used to test anthropometrics, the scaled joint wrap models better matched the regression than the scaled control point models. Detailed patient-specific anatomical data will improve model outcomes for clinical use; however, population studies may benefit from simplified geometry, especially with anthropometric scaling. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Efficacy and Safety of Concurrent Collagenase Clostridium Histolyticum Injections for 2 Dupuytren Contractures in the Same Hand: A Prospective, Multicenter Study.

PubMed

Gaston, R Glenn; Larsen, Søren Erik; Pess, Gary M; Coleman, Stephen; Dean, Brian; Cohen, Brian M; Kaufman, Gregory J; Tursi, James P; Hurst, Lawrence C

2015-10-01

To evaluate efficacy and safety of concurrent administration of 2 collagenase clostridium histolyticum (CCH) injections to treat 2 joints in the same hand with Dupuytren fixed flexion contractures (FFCs). Patients with 2 or more contractures in the same hand caused by palpable cords participated in a 60-day, multicenter, open-label, phase 3b study. Two 0.58 mg CCH doses were injected into 1 or 2 cords in the same hand (1 injection per affected joint) during the same visit. Finger extension was performed approximately 24, 48, or 72 or more hours later. Changes in FFC and range of motion, incidence of clinical success (FFC ≤ 5°), and adverse events (AEs) were summarized. The study enrolled 715 patients (725 treated joint pairs), and 714 patients (724 joint pairs) were analyzed for efficacy. At day 31, mean total FFC (sum of 2 treated joints) decreased 74%, from 98° to 27°. Mean total range of motion increased from 90° to 156°. The incidence of clinical success was 65% in metacarpophalangeal joints and 29% in proximal interphalangeal joints. Most treatment-related AEs were mild to moderate, resolving without intervention; the most common were swelling of treated extremity, contusion, and pain in extremity. The incidence of skin lacerations was 22% (160 of 715). Efficacy and safety were similar regardless of time to finger extension. Collagenase clostridium histolyticum can be used to effectively treat 2 affected joints concurrently without a greater risk of AEs than treatment of a single joint, with the exception of skin laceration. The incidence of clinical success in this study after 1 injection per joint was comparable to phase 3 study results after 3 or more injections per joint. Two concurrent CCH injections may allow more rapid overall treatment of multiple affected joints, and the ability to vary the time between CCH injection and finger extension may allow physicians and patients greater flexibility with scheduling treatment. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

[Demographic features and difficulties in rehabilitation in patients referred to hand rehabilitation unit for phalangeal fractures].

PubMed

Sahin, Füsun; Yücel, Serap Dalgiç; Yilmaz, Figen; Ergöz, Ernur; Kuran, Banu

2006-01-01

We evaluated demographic and occupational features of patients with phalangeal fractures of the hand, etiologies and types of injuries, and the results of rehabilitation. The study included 91 fingers of 62 patients (54 males, 8 females; mean age 28+/-13 years; range 4 to 59 years) who were referred to our hand rehabilitation unit for phalangeal fractures. Demographic features, the cause and localization of injury, the type of surgery, time from surgery to rehabilitation, and the follow-up period were determined. At the end of rehabilitation, range of motion (ROM) of the phalangeal joint and total ROM of the injured fingers were assessed using the Strickland-Glogovac rating system. A great majority of injuries were caused by work accidents, followed by sport injuries and falls occurring in students. Sixty patients (96.8%) were right-handed. The fractures occurred in the dominant hand in 29 patients (46.8%). The majority of patients (n=45) were primary school graduates. The most common mechanism of injury was accidents related to heavy work machinery (n=18). The most commonly injured finger and the phalanx were the third finger (n=25, 27.5%) and the proximal phalanx (n=59, 56.7%), respectively. Only 27 patients (43.6%) had a sufficient follow-up with a mean of 79.7+/-46.6 days (range 30 to 254 days). Following rehabilitation, the mean ROM and the total ROM were 45.0+/-22.9 degrees and 63.3+/-16.1 degrees for the injured joint and the thumb, and 31.3+/-22.5 degrees and 122+/-60.3 degrees for the injured joint and the other fingers, respectively. Our data provide important insight into appropriate treatment and rehabilitation of phalangeal fractures, in particular, shortcomings in the treatment and follow-up.

Use of a Multivector Mandibular Distractor for Treatment of Pediatric Proximal Interphalangeal Joint Pilon Fractures: A Case-Based Review.

PubMed

Pedreira, Rachel; Cho, Brian H; Geer, Angela; DeJesus, Ramon A

2018-04-01

The difficulties in surgical treatment of pilon fractures of the finger include fragment reconstitution and posthealing stiffness. In adults, external fixation with traction and early active range of motion (AROM)/passive range of motion (PROM) during healing is considered necessary for avoiding joint stiffness and attaining realignment. The authors present a unique approach to pediatric pilon fractures that uses open reduction and multivector external fixation with delayed AROM/PROM. Initial immobilization and significant traction allowed for joint realignment and prevented noncompliance with staged distraction. The authors believe this immobilization leads to a superior outcome because, unlike adults, children tend to avoid stiffness and a larger distraction force allowed for sufficient joint realignment to regain range of motion (ROM). A right-handed 13-year-old boy sustained a right ring finger fracture and presented 12 days later. Radiographs revealed a comminuted Salter-Harris 4 fracture of the middle phalanx. The patient underwent open reduction and placement of multivector external fixation using a pediatric mandibular distractor/fixator. Significant traction was applied to distract the finger to length. Hardware was removed 6 weeks postoperatively and AROM was initiated after splinting. The patient started PROM 8 weeks postoperatively. Strengthening was initiated 2 weeks later. ROM improved and rehabilitation was continued. The patient exhibited nearly equal grip strength 12 weeks postoperatively. At 14 months follow-up, radiographs showed complete healing and joint realignment. There was no deformity or pain and finger length was restored. Management of pediatric pilon fractures is rarely described and presents unique considerations. Early-stage traction and immobilization using a multivector mandibular fixator/distractor is suitable in a child because noncompliance is avoided and there is a decreased risk for stiffness. Combining early immobilization with subsequent-staged AROM, PROM, and strengthening resulted in no loss of ROM and maintained articular symmetry.

Tendon-bone graft for tendinous mallet fingers following failed splinting.

PubMed

Wang, Le; Zhang, Xu; Liu, Ze; Huang, Xiuge; Zhu, Hongwei; Yu, Yadong

2013-12-01

To describe and assess a surgical technique for the treatment of tendinous mallet fingers after failed conservative treatment. From January 2010 to March 2012, 28 tendinous mallet fingers in 28 patients were treated. All patients had greater than 25° extensor lags after 6 to 8 weeks of splinting. Four patients had a second trial of splinting, which also failed. A tendon-bone graft, taken from the extensor carpi radialis brevis and the third metacarpal base, was used for reconstruction. The mean time between the injury and operation was 74 days. The mean preoperative extension lag was 34°. Five patients reported pain in the distal interphalangeal joint. At the final follow-up, patients rated the level of pain on the distal interphalangeal and wrist joints using a visual analog scale. Joint motion was graded with the Crawford criteria. Hand function was assessed with the Disabilities of the Arm, Shoulder, and Hand questionnaire. Patients reported on their satisfaction based on the Michigan Hand Outcomes Questionnaire. Bone healing was achieved in all patients at a mean of 5 weeks. Position of bone graft was maintained until bone healing was evident in all cases. At the mean follow-up period of 15 months, nail deformity was not noted. No patient reported pain on the distal interphalangeal joint or wrist. The mean residual extension lag of the distal interphalangeal joints was 4°. The results showed that 24 digits were excellent and 4 were good based on the Crawford criteria. The Disabilities of the Arm, Shoulder, and Hand scores averaged 1, and 27 patients were satisfied with appearance of the hand. One patient sometimes felt uncomfortable regarding the appearance. A tendon-bone graft is a useful and reliable technique for the treatment of tendinous mallet fingers after failed splinting. Therapeutic IV. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Efficacy and safety of concurrent collagenase clostridium histolyticum injections for multiple Dupuytren contractures.

PubMed

Coleman, Stephen; Gilpin, David; Kaplan, F Thomas D; Houston, Anthony; Kaufman, Gregory J; Cohen, Brian M; Jones, Nigel; Tursi, James P

2014-01-01

To assess the safety and efficacy of 2 concurrent injections of collagenase clostridium histolyticum (CCH) in the same hand to treat multiple Dupuytren flexion contractures. In a multicenter, open-label phase IIIb study, 60 patients received two 0.58-mg CCH doses injected into cords affecting 2 joints in the same hand during 1 visit, followed by finger extension approximately 24 hours later. Efficacy at postinjection day 30 (change in flexion contracture and active range of motion, patient satisfaction, physician-rated improvement, and rates of clinical success [flexion contracture 5° or less]) and adverse events were summarized. The concurrent injections were most commonly administered in cords affecting metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints on the same finger (47%) or 2 MCP joints on different fingers of the same hand (37%). Mean total (sum of the 2 treated joints) flexion contracture decreased 76%, from 87° to 24° (MCP joints: 86%; PIP joints: 66%). Mean total range of motion increased from 100° to 161°. Clinical success was 76% for MCP joints and 33% for PIP joints. Most patients were very satisfied (60%) or quite satisfied (28%) with treatment. Most investigators rated treated joints as very much improved (55%) or much improved (37%). The most common treatment-related adverse events (> 75% of patients) were contusion, pain in extremity, and edema peripheral (local edema). Most adverse events were mild to moderate in severity. Serious complications included 1 pulley rupture related to study medication and 1 flexor tendon rupture (following conclusion of the study). There were no systemic complications. Results suggest that 2 affected joints can be effectively and safely treated with concurrent CCH injections. There was an increased incidence of some adverse events with concurrent treatment (pruritus, lymphadenopathy, blood blister, and skin laceration) compared with treatment of a single joint. High degrees of patient satisfaction and physician-rated improvement were reported. Therapeutic IV. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Flexible Piezoelectric Energy Harvesting from Mouse Click Motions

PubMed Central

Cha, Youngsu; Hong, Jin; Lee, Jaemin; Park, Jung-Min; Kim, Keehoon

2016-01-01

In this paper, we study energy harvesting from the mouse click motions of a robot finger and a human index finger using a piezoelectric material. The feasibility of energy harvesting from mouse click motions is experimentally and theoretically assessed. The fingers wear a glove with a pocket for including the piezoelectric material. We model the energy harvesting system through the inverse kinematic framework of parallel joints in a finger and the electromechanical coupling equations of the piezoelectric material. The model is validated through energy harvesting experiments in the robot and human fingers with the systematically varying load resistance. We find that energy harvesting is maximized at the matched load resistance to the impedance of the piezoelectric material, and the harvested energy level is tens of nJ. PMID:27399705

Extrinsic and intrinsic index finger muscle attachments in an OpenSim upper-extremity model.

PubMed

Lee, Jong Hwa; Asakawa, Deanna S; Dennerlein, Jack T; Jindrich, Devin L

2015-04-01

Musculoskeletal models allow estimation of muscle function during complex tasks. We used objective methods to determine possible attachment locations for index finger muscles in an OpenSim upper-extremity model. Data-driven optimization algorithms, Simulated Annealing and Hook-Jeeves, estimated tendon locations crossing the metacarpophalangeal (MCP), proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints by minimizing the difference between model-estimated and experimentally-measured moment arms. Sensitivity analysis revealed that multiple sets of muscle attachments with similar optimized moment arms are possible, requiring additional assumptions or data to select a single set of values. The most smooth muscle paths were assumed to be biologically reasonable. Estimated tendon attachments resulted in variance accounted for (VAF) between calculated moment arms and measured values of 78% for flex/extension and 81% for ab/adduction at the MCP joint. VAF averaged 67% at the PIP joint and 54% at the DIP joint. VAF values at PIP and DIP joints partially reflected the constant moment arms reported for muscles about these joints. However, all moment arm values found through optimization were non-linear and non-constant. Relationships between moment arms and joint angles were best described with quadratic equations for tendons at the PIP and DIP joints.

Deducing the reachable space from fingertip positions.

PubMed

Hai-Trieu Pham; Pathirana, Pubudu N

2015-01-01

The reachable space of the hand has received significant interests in the past from relevant medical researchers and health professionals. The reachable space was often computed from the joint angles acquired from a motion capture system such as gloves or markers attached to each bone of the finger. However, the contact between the hand and device can cause difficulties particularly for hand with injuries, burns or experiencing certain dermatological conditions. This paper introduces an approach to find the reachable space of the hand in a non-contact measurement form utilizing the Leap Motion Controller. The approach is based on the analysis of each position in the motion path of the fingertip acquired by the Leap Motion Controller. For each position of the fingertip, the inverse kinematic problem was solved under the physiological multiple constraints of the human hand to find a set of all possible configurations of three finger joints. Subsequently, all the sets are unified to form a set of all possible configurations specific for that motion. Finally, a reachable space is computed from the configuration corresponding to the complete extension and the complete flexion of the finger joint angles in this set.

Robust Hand Motion Tracking through Data Fusion of 5DT Data Glove and Nimble VR Kinect Camera Measurements

PubMed Central

Arkenbout, Ewout A.; de Winter, Joost C. F.; Breedveld, Paul

2015-01-01

Vision based interfaces for human computer interaction have gained increasing attention over the past decade. This study presents a data fusion approach of the Nimble VR vision based system, using the Kinect camera, with the contact based 5DT Data Glove. Data fusion was achieved through a Kalman filter. The Nimble VR and filter output were compared using measurements performed on (1) a wooden hand model placed in various static postures and orientations; and (2) three differently sized human hands during active finger flexions. Precision and accuracy of joint angle estimates as a function of hand posture and orientation were determined. Moreover, in light of possible self-occlusions of the fingers in the Kinect camera images, data completeness was assessed. Results showed that the integration of the Data Glove through the Kalman filter provided for the proximal interphalangeal (PIP) joints of the fingers a substantial improvement of 79% in precision, from 2.2 deg to 0.9 deg. Moreover, a moderate improvement of 31% in accuracy (being the mean angular deviation from the true joint angle) was established, from 24 deg to 17 deg. The metacarpophalangeal (MCP) joint was relatively unaffected by the Kalman filter. Moreover, the Data Glove increased data completeness, thus providing a substantial advantage over the sole use of the Nimble VR system. PMID:26694395

Robust Hand Motion Tracking through Data Fusion of 5DT Data Glove and Nimble VR Kinect Camera Measurements.

PubMed

Arkenbout, Ewout A; de Winter, Joost C F; Breedveld, Paul

2015-12-15

Vision based interfaces for human computer interaction have gained increasing attention over the past decade. This study presents a data fusion approach of the Nimble VR vision based system, using the Kinect camera, with the contact based 5DT Data Glove. Data fusion was achieved through a Kalman filter. The Nimble VR and filter output were compared using measurements performed on (1) a wooden hand model placed in various static postures and orientations; and (2) three differently sized human hands during active finger flexions. Precision and accuracy of joint angle estimates as a function of hand posture and orientation were determined. Moreover, in light of possible self-occlusions of the fingers in the Kinect camera images, data completeness was assessed. Results showed that the integration of the Data Glove through the Kalman filter provided for the proximal interphalangeal (PIP) joints of the fingers a substantial improvement of 79% in precision, from 2.2 deg to 0.9 deg. Moreover, a moderate improvement of 31% in accuracy (being the mean angular deviation from the true joint angle) was established, from 24 deg to 17 deg. The metacarpophalangeal (MCP) joint was relatively unaffected by the Kalman filter. Moreover, the Data Glove increased data completeness, thus providing a substantial advantage over the sole use of the Nimble VR system.

Frequency of inflammatory-like MR imaging findings in asymptomatic fingers of healthy volunteers.

PubMed

Agten, Christoph A; Rosskopf, Andrea B; Jonczy, Maciej; Brunner, Florian; Pfirrmann, Christian W A; Buck, Florian M

2018-02-01

To describe the frequency of inflammatory-like findings on MR imaging in asymptomatic volunteers and compare them with patients with known rheumatoid arthritis and psoriatic arthritis. MR images of fingers in 42 asymptomatic volunteers and 33 patients with rheumatoid/psoriatic arthritis were analyzed. The Outcome Measures in Rheumatology Clinical Trials (OMERACT) Rheumatoid/Psoriatic Arthritis MRI Scoring System (RAMRIS/PsAMRIS) and tenosynovitis scoring system were used to assess: bone marrow edema (BME), erosions, tendon sheath fluid/tenosynovitis, joint effusion, and soft-tissue edema. Findings and scores were compared between volunteers and patients. Inter-reader agreement was calculated (intraclass correlation coefficients, ICC). In volunteers, tendon sheath fluid was very common in at least one location (42/42 volunteers for reader 1, 34/42 volunteers for reader 2). BME, erosions, joint effusion, and soft-tissue edema were absent (except one BME in the 3rd proximal phalanx for reader 1). Tendon sheath fluid scores in volunteers and tenosynovitis scores in patients were high (reader 1, 7.17 and 5.39; reader 2, 2.31 and 5.45). Overall, inter-reader agreement was substantial (ICC = 0.696-0.844), except for tendon sheath fluid (ICC = 0.258). Fluid in the finger flexor tendon sheaths may be a normal finding and without gadolinium administration should not be interpreted as tenosynovitis. Bone marrow edema, erosions, joint effusion, and soft-tissue edema in the fingers most likely reflect pathology if present.

Principal components of hand kinematics and neurophysiological signals in motor cortex during reach to grasp movements

PubMed Central

Aggarwal, Vikram; Thakor, Nitish V.; Schieber, Marc H.

2014-01-01

A few kinematic synergies identified by principal component analysis (PCA) account for most of the variance in the coordinated joint rotations of the fingers and wrist used for a wide variety of hand movements. To examine the possibility that motor cortex might control the hand through such synergies, we collected simultaneous kinematic and neurophysiological data from monkeys performing a reach-to-grasp task. We used PCA, jPCA and isomap to extract kinematic synergies from 18 joint angles in the fingers and wrist and analyzed the relationships of both single-unit and multiunit spike recordings, as well as local field potentials (LFPs), to these synergies. For most spike recordings, the maximal absolute cross-correlations of firing rates were somewhat stronger with an individual joint angle than with any principal component (PC), any jPC or any isomap dimension. In decoding analyses, where spikes and LFP power in the 100- to 170-Hz band each provided better decoding than other LFP-based signals, the first PC was decoded as well as the best decoded joint angle. But the remaining PCs and jPCs were predicted with lower accuracy than individual joint angles. Although PCs, jPCs or isomap dimensions might provide a more parsimonious description of kinematics, our findings indicate that the kinematic synergies identified with these techniques are not represented in motor cortex more strongly than the original joint angles. We suggest that the motor cortex might act to sculpt the synergies generated by subcortical centers, superimposing an ability to individuate finger movements and adapt the hand to grasp a wide variety of objects. PMID:24990564

Distribution of finger nodes and their association with underlying radiographic features of osteoarthritis.

PubMed

Rees, Frances; Doherty, Sally; Hui, Michelle; Maciewicz, Rose; Muir, Kenneth; Zhang, Weiya; Doherty, Michael

2012-04-01

To determine the distribution of clinically palpable hand interphalangeal (IP) nodes at each finger and thumb joint in a population with nodes, the influence of left or right hand dominance and sex on the development of nodes, and the association between nodes and underlying radiographic features of osteoarthritis (OA). We performed a cross-sectional analysis of participants in the Genetics of Osteoarthritis and Lifestyle (GOAL) study who had ≥1 Heberden's nodes or Bouchard's nodes on clinical examination. Frequencies (%) of nodes were described for each IP joint in the hand. Associations between nodes and underlying radiographic OA were shown with odds ratios (ORs) and 95% confidence intervals. A logistic regression model was used to adjust for the following confounding factors: age, sex, body mass index, left or right hand dominance, hand trauma, occupation with heavy manual activity, and participation in sports. Of the 3,170 GOAL participants, 1,939 had ≥1 nodes (mean age 68 years, 54% women). The distal IP joints of the index finger were the most frequently affected, followed by the thumb IP joint. Nodes were more common in dominant hands and women. There was a significant association between nodes and underlying radiographic OA (OR range 2.26-21.23). This association was stronger for joint space narrowing than for osteophytes. A dose-response relationship was found between clinical severity of Heberden's nodes and underlying radiographic change. Our study supports the positive association between nodes and radiographic OA, especially narrowing, and the influence of sex and left or right hand dominance on development of nodes. In this age group, presence of nodes may be taken as an indication of underlying small joint OA. Copyright © 2012 by the American College of Rheumatology.

Finger muscle attachments for an OpenSim upper-extremity model.

PubMed

Lee, Jong Hwa; Asakawa, Deanna S; Dennerlein, Jack T; Jindrich, Devin L

2015-01-01

We determined muscle attachment points for the index, middle, ring and little fingers in an OpenSim upper-extremity model. Attachment points were selected to match both experimentally measured locations and mechanical function (moment arms). Although experimental measurements of finger muscle attachments have been made, models differ from specimens in many respects such as bone segment ratio, joint kinematics and coordinate system. Likewise, moment arms are not available for all intrinsic finger muscles. Therefore, it was necessary to scale and translate muscle attachments from one experimental or model environment to another while preserving mechanical function. We used a two-step process. First, we estimated muscle function by calculating moment arms for all intrinsic and extrinsic muscles using the partial velocity method. Second, optimization using Simulated Annealing and Hooke-Jeeves algorithms found muscle-tendon paths that minimized root mean square (RMS) differences between experimental and modeled moment arms. The partial velocity method resulted in variance accounted for (VAF) between measured and calculated moment arms of 75.5% on average (range from 48.5% to 99.5%) for intrinsic and extrinsic index finger muscles where measured data were available. RMS error between experimental and optimized values was within one standard deviation (S.D) of measured moment arm (mean RMS error = 1.5 mm < measured S.D = 2.5 mm). Validation of both steps of the technique allowed for estimation of muscle attachment points for muscles whose moment arms have not been measured. Differences between modeled and experimentally measured muscle attachments, averaged over all finger joints, were less than 4.9 mm (within 7.1% of the average length of the muscle-tendon paths). The resulting non-proprietary musculoskeletal model of the human fingers could be useful for many applications, including better understanding of complex multi-touch and gestural movements.

Finger Muscle Attachments for an OpenSim Upper-Extremity Model

PubMed Central

Lee, Jong Hwa; Asakawa, Deanna S.; Dennerlein, Jack T.; Jindrich, Devin L.

2015-01-01

We determined muscle attachment points for the index, middle, ring and little fingers in an OpenSim upper-extremity model. Attachment points were selected to match both experimentally measured locations and mechanical function (moment arms). Although experimental measurements of finger muscle attachments have been made, models differ from specimens in many respects such as bone segment ratio, joint kinematics and coordinate system. Likewise, moment arms are not available for all intrinsic finger muscles. Therefore, it was necessary to scale and translate muscle attachments from one experimental or model environment to another while preserving mechanical function. We used a two-step process. First, we estimated muscle function by calculating moment arms for all intrinsic and extrinsic muscles using the partial velocity method. Second, optimization using Simulated Annealing and Hooke-Jeeves algorithms found muscle-tendon paths that minimized root mean square (RMS) differences between experimental and modeled moment arms. The partial velocity method resulted in variance accounted for (VAF) between measured and calculated moment arms of 75.5% on average (range from 48.5% to 99.5%) for intrinsic and extrinsic index finger muscles where measured data were available. RMS error between experimental and optimized values was within one standard deviation (S.D) of measured moment arm (mean RMS error = 1.5 mm < measured S.D = 2.5 mm). Validation of both steps of the technique allowed for estimation of muscle attachment points for muscles whose moment arms have not been measured. Differences between modeled and experimentally measured muscle attachments, averaged over all finger joints, were less than 4.9 mm (within 7.1% of the average length of the muscle-tendon paths). The resulting non-proprietary musculoskeletal model of the human fingers could be useful for many applications, including better understanding of complex multi-touch and gestural movements. PMID:25853869

Comparative study of the detection of joint injury in early-stage rheumatoid arthritis by magnetic resonance imaging of the wrist and finger joints and physical examination.

PubMed

Tamai, Mami; Kawakami, Atsushi; Iwamoto, Naoki; Kawashiri, Shin-Ya; Fujikawa, Keita; Aramaki, Toshiyuki; Kita, Junko; Okada, Akitomo; Koga, Tomohiro; Arima, Kazuhiko; Kamachi, Makoto; Yamasaki, Satoshi; Nakamura, Hideki; Ida, Hiroaki; Origuchi, Tomoki; Takao, Shoichiro; Aoyagi, Kiyoshi; Uetani, Masataka; Eguchi, Katsumi

2011-03-01

To verify whether magnetic resonance imaging (MRI)-proven joint injury is sensitive as compared with joint injury determined by physical examination. MRI of the wrist and finger joints of both hands was examined in 51 early-stage rheumatoid arthritis (RA) patients by both plain and gadolinium diethylenetriaminepentaacetic acid-enhanced MRI. Synovitis, bone edema, and bone erosion (the latter two included as bone lesions at the wrist joints); metacarpophalangeal joints; and proximal interphalangeal joints were considered as MRI-proven joint injury. Japan College of Rheumatology-certified rheumatologists had given a physical examination just before the MRI study. The presence of tender and/or swollen joints in the same fields as MRI was considered as joint injury on physical examination. The association of MRI-proven joint injury with physical examination-proven joint injury was examined. A total of 1,110 sites were available to be examined. MRI-proven joint injury was found in 521 sites, whereas the other 589 sites were normal. Physical examination-proven joint injury was found in 305 sites, which was significantly low as compared with MRI-proven joint injury (P = 1.1 × 10(-12) versus MRI). Joint injury on physical examination was not found in 81.5% of the sites where MRI findings were normal. Furthermore, an association of the severity of MRI-proven joint injury with that of joint injury on physical examination was clearly demonstrated (P = 1.6 × 10(-15), r(s) = 0.469). Our present data suggest that MRI is not only sensitive but accurately reflects the joint injury in patients with early-stage RA. Copyright © 2011 by the American College of Rheumatology.

Power assist EVA glove development

NASA Technical Reports Server (NTRS)

Main, John A.; Peterson, Steven W.; Strauss, Alvin M.

1992-01-01

Structural modeling of the EVA glove indicates that flexibility in the metacarpophalangeal (MCP) joint can be improved by selectively lowering the elasticity of the glove fabric. Two strategies are used to accomplish this. One method uses coil springs on the back of the glove to carry the tension in the glove skin due to pressurization. These springs carry the loads normally borne by the glove fabric, but are more easily deformed. An active system was also designed for the same purpose and uses gas filled bladders attached to the back of the EVA glove that change the dimensions of the back of the glove and allow the glove to bend at the MCP joint, thus providing greater flexibility at this joint. A threshold control scheme was devised to control the action of the joint actuators. Input to the controller was provided by thin resistive pressure sensors placed between the hand and the pressurized glove. The pressure sensors consist of a layer of polyester film that has a thin layer of ink screened on the surface. The resistivity of the ink is pressure dependent, so an extremely thin pressure sensor can be fabricated by covering the ink patch with another layer of polyester film and measuring the changing resistance of the ink with a bridge circuit. In order to sense the force between the hand and the glove at the MCP joint, a sensor was placed on the palmar face of the middle finger. The resultant signal was used by the controller to decide whether to fill or exhaust the bladder actuators on the back of the glove. The information from the sensor can also be used to evaluate the effectiveness of a given control scheme or glove design since the magnitude of the measured pressures gives some idea of the torque required to bend a glove finger at the MCP joint. Tests of this actuator, sensor, and control system were conducted in an 57.2 kPa glove box by performing a series of 90 degree finger bends with a glove without an MCP joint assembly, a glove with the coil spring assembly, and with the four fingered actuated glove. The tests of these three glove designs confirm the validity of the model.

An evaluation of the spring finger solder joints on SA1358-10 and SA2052-4 connector assemblies (MC3617,W87).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kilgo, Alice C.; Vianco, Paul Thomas; Hlava, Paul Frank

2006-08-01

The SA1358-10 and SA2052-4 circular JT Type plug connectors are used on a number of nuclear weapons and Joint Test Assembly (JTA) systems. Prototype units were evaluated for the following specific defects associated with the 95Sn-5Sb (Sn-Sb, wt.%) solder joint used to attach the beryllium-copper (BeCu) spring fingers to the aluminum (Al) connector shell: (1) extended cracking within the fillet; (2) remelting of the solder joint during the follow-on, soldering step that attached the EMR adapter ring to the connector shell (and/or soldering the EMR shell to the adapter ring) that used the lower melting temperature 63Sn-37Pb (Sn-Pb) alloy; andmore » (3) spalling of the Cd (Cr) layer overplating layer from the fillet surface. Several pedigrees of connectors were evaluated, which represented older fielded units as well as those assemblies that were recently constructed at Kansas City Plant. The solder joints were evaluated that were in place on connectors made with the current soldering process as well as an alternative induction soldering process for attaching the EMR adapter ring to the shell. Very similar observations were made, which crossed the different pedigrees of parts and processes. The extent of cracking in the top side fillets varied between the different connector samples and likely the EMR adapter ring to the shell. Very similar observations were made, which crossed the different pedigrees of parts and processes. The extent of cracking in the top side fillets varied between the different connector samples and likely reflected the different extents to which the connector was mated to its counterpart assembly. In all cases, the spring finger solder joints on the SA1358-10 connectors were remelted as a result of the subsequent EMR adapter ring attachment process. Spalling of the Cd (Cr) overplating layer was also observed for these connectors, which was a consequence of the remelting activity. On the other hand, the SA2052-4 connector did not exhibit evidence of remelting of the spring finger solder joint. The Cd (Cr) layer did not show signs of spalling. These results suggested that, due to the size of the SA1358-10 connector, any of the former or current soldering processes used to attach the EMR adapter ring and/or EMR shell to the connector shell, requires a level of heat energy that will always result in the remelting of the spring finger solder joint attached with either the Sn-Ag or the Sn-Sb alloy. Lastly, it was construed that the induction soldering process, which is used to attach the EMR adapter ring onto the shell, was more likely to have caused the remelting event rather than the more localized heat source of the hand soldering iron used to attach the EMR shell to the adapter ring.« less

Geometric features of workspace and joint-space paths of 3D reaching movements.

PubMed

Klein Breteler, M D; Meulenbroek, R G; Gielen, S C

1998-11-01

The present study focuses on geometric features of workspace and joint-space paths of three-dimensional reaching movements. Twelve subjects repeatedly performed a three-segment, triangular-shaped movement pattern in an approximately 60 degrees tilted horizontal plane. Task variables elicited movement patterns that varied in position, rotational direction and speed. Trunk, arm, hand and finger-tip movements were recorded by means of a 3D motion-tracking system. Angular excursions of the shoulder and elbow joints were extracted from position data. Analyses of the shape of 3D workspace and joint-space paths focused on the extent to which the submovements were produced in a plane, and on the curvature of the central parts of the submovements. A systematic tendency to produce movements in a plane was found in addition to an increase of finger-tip path curvature with increasing speed. The findings are discussed in relation to the role of optimization principles in trajectory-formation models.

The immediate effects of therapeutic keyboard music playing for finger training in adults undergoing hand rehabilitation.

PubMed

Zhang, Xiaoying; Liu, Songhuai; Yang, Degang; Du, Liangjie; Wang, Ziyuan

2016-08-01

[Purpose] The purpose of this study was to examine the immediate effects of therapeutic keyboard music playing on the finger function of subjects' hands through measurements of the joint position error test, surface electromyography, probe reaction time, and writing time. [Subjects and Methods] Ten subjects were divided randomly into experimental and control groups. The experimental group used therapeutic keyboard music playing and the control group used grip training. All subjects were assessed and evaluated by the joint position error test, surface electromyography, probe reaction time, and writing time. [Results] After accomplishing therapeutic keyboard music playing and grip training, surface electromyography of the two groups showed no significant change, but joint position error test, probe reaction time, and writing time obviously improved. [Conclusion] These results suggest that therapeutic keyboard music playing is an effective and novel treatment for improving joint position error test scores, probe reaction time, and writing time, and it should be promoted widely in clinics.

"Finger Kits:" An Interactive Demonstration of Biomaterials and Engineering for Elementary School Students

ERIC Educational Resources Information Center

Canavan, Heather E.; Stanton, Michael; Lopez, Kaori; Grubin, Catherine; Graham, Daniel J.

2008-01-01

This article describes a hands-on activity and demonstration developed at the University of Washington and further reined at the University of New Mexico. In this activity, the authors present a real-world problem to the student: Someone has an injured finger joint, and the students in the class need to design an implant to replace it. After…

Can a Soft Robotic Probe Use Stiffness Control Like a Human Finger to Improve Efficacy of Haptic Perception?

PubMed

Sornkarn, Nantachai; Nanayakkara, Thrishantha

2017-01-01

When humans are asked to palpate a soft tissue to locate a hard nodule, they regulate the stiffness, speed, and force of the finger during examination. If we understand the relationship between these behavioral variables and haptic information gain (transfer entropy) during manual probing, we can improve the efficacy of soft robotic probes for soft tissue palpation, such as in tumor localization in minimally invasive surgery. Here, we recorded the muscle co-contraction activity of the finger using EMG sensors to address the question as to whether joint stiffness control during manual palpation plays an important role in the haptic information gain. To address this question, we used a soft robotic probe with a controllable stiffness joint and a force sensor mounted at the base to represent the function of the tendon in a biological finger. Then, we trained a Markov chain using muscle co-contraction patterns of human subjects, and used it to control the stiffness of the soft robotic probe in the same soft tissue palpation task. The soft robotic experiments showed that haptic information gain about the depth of the hard nodule can be maximized by varying the internal stiffness of the soft probe.

The added value of measuring thumb and finger strength when comparing strength measurements in hypoplastic thumb patients.

PubMed

Molenaar, H M Ties; Selles, Ruud W; de Kraker, Marjolein; Stam, Henk J; Hovius, Steven E R

2013-10-01

When interventions to the hand are aimed at improving function of specific fingers or the thumb, the RIHM (Rotterdam Intrinsic Hand Myometer) is a validated tool and offers more detailed information to assess strength of the involved joints besides grip and pinch measurements. In this study, strength was measured in 65 thumbs in 40 patients diagnosed with thumb hypoplasia. These 65 thumbs were classified according to Blauth. Longitudinal radial deficiencies were also classified. The strength measurements comprised of grip, tip, tripod and key pinch. Furthermore palmar abduction and opposition of the thumb as well as abduction of the index and little finger were measured with the RIHM. For all longitudinal radial deficiency patients, grip and pinch strength as well as palmar abduction and thumb opposition were significantly lower than reference values (P<0.001). However, strength in the index finger abduction and the little finger abduction was maintained or decreased to a lesser extent according to the degree of longitudinal radial deficiency. All strength values decreased with increasing Blauth-type. Blauth-type II hands (n=15) with flexor digitorum superficialis 4 opposition transfer including stabilization of the metacarpophalangeal joint showed a trend toward a higher opposition strength without reaching statistical significance (P=0.094),however compared to non-operated Blauth-type II hands (n=6) they showed a lower grip strength (P=0.019). The RIHM is comparable in accuracy to other strength dynamometers. Using the RIHM, we were able to illustrate strength patterns on finger-specific level, showing added value when evaluating outcome in patients with hand related problems. © 2013.

[Study of mechanical effects of the EVA glove on finger base with finite element modeling].

PubMed

Li, Zhuoyou; Ding, Li; Yue, Guodong

2013-08-01

The hand strength of astronauts, when they are outside the space capsule, is highly influenced by the residual pressure (the pressure difference between inside pressure and outside one of the suit) of extravehicular activity spacesuit glove and the pressure exerted by braided fabric. The hand strength decreases significantly on extravehicular activity, severely reducing the operation efficiency. To measure mechanical influence caused by spacesuit glove on muscle-tendon and joints, the present paper analyzes the movement anatomy and biomechanical characteristics of gripping, and then proposes a grip model. With phalangeal joint simplified as hinges, seven muscles as a finger grip energy unit, the Hill muscle model was used to compute the effects. We also used ANSYS in this study to establish a 3-D finite element model of an index finger which included both bones and muscles with glove, and then we verified the model. This model was applied to calculate the muscle stress in various situations of bare hands or hands wearing gloves in three different sizes. The results showed that in order to achieve normal grip strength with the influence caused by superfluous press, the finger's muscle stress should be increased to 5.4 times of that in normal situation, with most of the finger grip strength used to overcome the influence of superfluous pressure. When the gap between the finger surface and the glove is smaller, the mechanical influence which superfluous press made will decrease. The results would provide a theoretical basis for the design of the EVA Glove.

Digital ranges of motion: normal values in young adults.

PubMed

Mallon, W J; Brown, H R; Nunley, J A

1991-09-01

Analysis of the range of motion of fingers was done in young (eighteen to thirty-five year old) adult volunteers with no history of previous injury to their hands. The data show that there are slight differences between the individual digits. Notably, metacarpophalangeal flexion and total active motion increase linearly in proceeding from the index to the small finger. There were also minor differences in comparing sexes. Women have greater extension at the metacarpophalangeal joint in both active and passive motion and have a greater total active motion at all digits as a result. A significant tenodesis effect was found at the distal interphalangeal joint in normal subjects. No differences were found that could be attributable to handedness.

Towards real-time medical diagnostics using hyperspectral imaging technology

NASA Astrophysics Data System (ADS)

Bjorgan, Asgeir; Randeberg, Lise L.

2015-07-01

Hyperspectral imaging provides non-contact, high resolution spectral images which has a substantial diagnostic potential. This can be used for e.g. diagnosis and early detection of arthritis in finger joints. Processing speed is currently a limitation for clinical use of the technique. A real-time system for analysis and visualization using GPU processing and threaded CPU processing is presented. Images showing blood oxygenation, blood volume fraction and vessel enhanced images are among the data calculated in real-time. This study shows the potential of real-time processing in this context. A combination of the processing modules will be used in detection of arthritic finger joints from hyperspectral reflectance and transmittance data.

Local sensory control of a dexterous end effector

NASA Technical Reports Server (NTRS)

Pinto, Victor H.; Everett, Louis J.; Driels, Morris

1990-01-01

A numerical scheme was developed to solve the inverse kinematics for a user-defined manipulator. The scheme was based on a nonlinear least-squares technique which determines the joint variables by minimizing the difference between the target end effector pose and the actual end effector pose. The scheme was adapted to a dexterous hand in which the joints are either prismatic or revolute and the fingers are considered open kinematic chains. Feasible solutions were obtained using a three-fingered dexterous hand. An algorithm to estimate the position and orientation of a pre-grasped object was also developed. The algorithm was based on triangulation using an ideal sensor and a spherical object model. By choosing the object to be a sphere, only the position of the object frame was important. Based on these simplifications, a minimum of three sensors are needed to find the position of a sphere. A two dimensional example to determine the position of a circle coordinate frame using a two-fingered dexterous hand was presented.

[The development of a finger joint phantom for the optical simulation of early inflammatory rheumatic changes].

PubMed

Prapavat, V; Runge, W; Mans, J; Krause, A; Beuthan, J; Müller, G

1997-11-01

In the field of rheumatology, conventional diagnostic methods permit the detection only of advanced stages of the disease, which is at odds with the current clinical demand for the early diagnosis of inflammatory rheumatic diseases. Prompted by current needs, we developed a finger joint phantom that enables the optical and geometrical simulation of an early stage of rheumatoid arthritis (RA). The results presented here form the experimental basis for an evaluation of new RA diagnostic systems based on near infrared light. The early stage of RA is characterised mainly by a vigorous proliferation of the synovial membrane and clouding of the synovial fluid. Using a double-integrating-sphere technique, the absorption and scattering coefficients (mua, mus') are experimentally determined for healthy and pathologically altered synovial fluid and capsule tissue. Using a variable mixture of Intralipid Indian ink and water as a scattering/absorption medium, the optical properties of skin, synovial fluid or capsule can be selected individually. Since the optical and geometrical properties of bone tissue remain constant in early-stage RA, a solid material is used for its simulation. Using the finger joint phantom described herein, the optical properties of joint regions can be adjusted specifically, enabling an evaluation of their effects on an optical signal--for example, during fluorography--and the investigation of these effects for diagnostically useful information. The experimental foundation for the development of a new optical system for the early diagnosis of RA has now been laid.

Optical clearing of human skin for the enhancement of optical imaging of proximal interphalangeal joints

NASA Astrophysics Data System (ADS)

Kolesnikova, Ekaterina A.; Kolesnikov, Aleksandr S.; Zabarylo, Urszula; Minet, Olaf; Genina, Elina A.; Bashkatov, Alexey N.; Tuchin, Valery V.

2014-01-01

We are proposing a new method for enhancement of optical imaging of proximal interphalangeal (PIP) joints in humans at skin using optical clearing technique. A set of illuminating laser diodes with the wavelengths 670, 820, and 904 nm were used as a light source. The laser diodes, monochromatic digital CCD camera and specific software allowed for detection of the finger joint image in a transillumination mode. The experiments were carried out in vivo with human fingers. Dehydrated glycerol and hand cream with urea (5%) were used as optical clearing agents (OCAs). The contrast of the obtained images was analyzed to determine the effect of the OCA. It was found that glycerol application to the human skin during 60 min caused the decrease of contrast in 1.4 folds for 670 nm and the increase of contrast in 1.5 and 1.7 folds for 820 nm and 904 nm, respectively. At the same time, the hand cream application to the human skin during 60 min caused the decrease of contrast in 1.1 folds for 670 nm and the increase of contrast in 1.3 and 1.1 folds for 820 nm and 904 nm, respectively. The results have shown that glycerol and the hand cream with 5% urea allow for obtaining of more distinct image of finger joint in the NIR. Obtained data can be used for development of optical diagnostic methods of rheumatoid arthritis.

Continuous and simultaneous estimation of finger kinematics using inputs from an EMG-to-muscle activation model.

PubMed

Ngeo, Jimson G; Tamei, Tomoya; Shibata, Tomohiro

2014-08-14

Surface electromyography (EMG) signals are often used in many robot and rehabilitation applications because these reflect motor intentions of users very well. However, very few studies have focused on the accurate and proportional control of the human hand using EMG signals. Many have focused on discrete gesture classification and some have encountered inherent problems such as electro-mechanical delays (EMD). Here, we present a new method for estimating simultaneous and multiple finger kinematics from multi-channel surface EMG signals. In this study, surface EMG signals from the forearm and finger kinematic data were extracted from ten able-bodied subjects while they were tasked to do individual and simultaneous multiple finger flexion and extension movements in free space. Instead of using traditional time-domain features of EMG, an EMG-to-Muscle Activation model that parameterizes EMD was used and shown to give better estimation performance. A fast feed forward artificial neural network (ANN) and a nonparametric Gaussian Process (GP) regressor were both used and evaluated to estimate complex finger kinematics, with the latter rarely used in the other related literature. The estimation accuracies, in terms of mean correlation coefficient, were 0.85 ± 0.07, 0.78 ± 0.06 and 0.73 ± 0.04 for the metacarpophalangeal (MCP), proximal interphalangeal (PIP) and the distal interphalangeal (DIP) finger joint DOFs, respectively. The mean root-mean-square error in each individual DOF ranged from 5 to 15%. We show that estimation improved using the proposed muscle activation inputs compared to other features, and that using GP regression gave better estimation results when using fewer training samples. The proposed method provides a viable means of capturing the general trend of finger movements and shows a good way of estimating finger joint kinematics using a muscle activation model that parameterizes EMD. The results from this study demonstrates a potential control strategy based on EMG that can be applied for simultaneous and continuous control of multiple DOF(s) devices such as robotic hand/finger prostheses or exoskeletons.

A finger exoskeleton for rehabilitation and brain image study.

PubMed

Tang, Zhenjin; Sugano, Shigeki; Iwata, Hiroyasu

2013-06-01

This paper introduces the design, fabrication and evaluation of the second generation prototype of a magnetic resonance compatible finger rehabilitation robot. It can not only be used as a finger rehabilitation training tool after a stroke, but also to study the brain's recovery process during the rehabilitation therapy (ReT). The mechanical design of the current generation has overcome the disadvantage in the previous version[13], which can't provide precise finger trajectories during flexion and extension motion varying with different finger joints' torques. In addition, in order to study the brain activation under different training strategies, three control modes have been developed, compared to only one control mode in the last prototype. The current prototype, like the last version, uses an ultrasonic motor as its actuator to enable the patient to do extension and flexion rehabilitation exercises in two degrees of freedom (DOF) for each finger. Finally, experiments have been carried out to evaluate the performances of this device.

Selective recruitment of single motor units in human flexor digitorum superficialis muscle during flexion of individual fingers.

PubMed

Butler, T J; Kilbreath, S L; Gorman, R B; Gandevia, S C

2005-08-15

Flexor digitorum superficialis (FDS) is an extrinsic multi-tendoned muscle which flexes the proximal interphalangeal joints of the four fingers. It comprises four digital components, each with a tendon that inserts onto its corresponding finger. To determine the degree to which these digital components can be selectively recruited by volition, we recorded the activity of a single motor unit in one component via an intramuscular electrode while the subject isometrically flexed each of the remaining fingers, one at a time. The finger on which the unit principally acted was defined as the 'test finger' and that which flexed isometrically was the 'active' finger. Activity in 79 units was recorded. Isometric finger flexion forces of 50% maximum voluntary contraction (MVC) activated less than 50% of single units in components of FDS acting on fingers that were not voluntarily flexed. With two exceptions, the median recruitment threshold for all active-test finger combinations involving the index, middle, ring and little finger test units was between 49 and 60% MVC (60% MVC being the value assigned to those not recruited). The exceptions were flexion of the little finger while recording from ring finger units (median: 40% MVC), and vice versa (median: 2% MVC). For all active-test finger combinations, only 35/181 units were activated when the active finger flexed at less than 20% MVC, and the fingers were adjacent for 28 of these. Functionally, to recruit FDS units during grasping and lifting, relatively heavy objects were required, although systematic variation occurred with the width of the object. In conclusion, FDS components can be selectively activated by volition and this may be especially important for grasping at high forces with one or more fingers.

Patient-based outcomes following surgical debridement and flap coverage of digital mucous cysts.

PubMed

Hojo, Junya; Omokawa, Shohei; Shigematsu, Koji; Onishi, Tadanobu; Murata, Keiichi; Tanaka, Yasuhito

2016-01-01

The purpose of this prospective cohort study was to evaluate patient-based outcomes and complications following excision of mucous cysts, joint debridement, and closure with one of three types of local flaps. From 2000-2011, 35 consecutive patients with 37 digital mucous cysts were treated surgically. The surgical procedure included excision of the cyst together with the attenuated skin, joint debridement on the affected side including capsulectomy, and removal of osteophytes. Depending on the size and location of the cyst, the skin defect was covered by a transposition flap (31 cysts), an advancement flap (two cysts), or a rotation flap (four cysts). At an average follow-up time of 4 years, 4 months, there was no wound infection, flap necrosis, or joint stiffness. Preoperative nail ridging resolved in seven of nine fingers, and no nail deformities developed after surgery. One cyst, treated with a transposition flap, recurred 10 months after surgery. The average satisfaction score for the affected finger significantly improved from 4.3 to 6.8, and the average pain score decreased from 4.7 to 2.3. This treatment protocol provides reliable results. Patients were satisfied with the reduction of associated pain and the postoperative appearance of the treated finger, and postoperative complications were minimal.

Computer-aided interpretation approach for optical tomographic images

NASA Astrophysics Data System (ADS)

Klose, Christian D.; Klose, Alexander D.; Netz, Uwe J.; Scheel, Alexander K.; Beuthan, Jürgen; Hielscher, Andreas H.

2010-11-01

A computer-aided interpretation approach is proposed to detect rheumatic arthritis (RA) in human finger joints using optical tomographic images. The image interpretation method employs a classification algorithm that makes use of a so-called self-organizing mapping scheme to classify fingers as either affected or unaffected by RA. Unlike in previous studies, this allows for combining multiple image features, such as minimum and maximum values of the absorption coefficient for identifying affected and not affected joints. Classification performances obtained by the proposed method were evaluated in terms of sensitivity, specificity, Youden index, and mutual information. Different methods (i.e., clinical diagnostics, ultrasound imaging, magnet resonance imaging, and inspection of optical tomographic images), were used to produce ground truth benchmarks to determine the performance of image interpretations. Using data from 100 finger joints, findings suggest that some parameter combinations lead to higher sensitivities, while others to higher specificities when compared to single parameter classifications employed in previous studies. Maximum performances are reached when combining the minimum/maximum ratio of the absorption coefficient and image variance. In this case, sensitivities and specificities over 0.9 can be achieved. These values are much higher than values obtained when only single parameter classifications were used, where sensitivities and specificities remained well below 0.8.

Finger crease pattern recognition using Legendre moments and principal component analysis

NASA Astrophysics Data System (ADS)

Luo, Rongfang; Lin, Tusheng

2007-03-01

The finger joint lines defined as finger creases and its distribution can identify a person. In this paper, we propose a new finger crease pattern recognition method based on Legendre moments and principal component analysis (PCA). After obtaining the region of interest (ROI) for each finger image in the pre-processing stage, Legendre moments under Radon transform are applied to construct a moment feature matrix from the ROI, which greatly decreases the dimensionality of ROI and can represent principal components of the finger creases quite well. Then, an approach to finger crease pattern recognition is designed based on Karhunen-Loeve (K-L) transform. The method applies PCA to a moment feature matrix rather than the original image matrix to achieve the feature vector. The proposed method has been tested on a database of 824 images from 103 individuals using the nearest neighbor classifier. The accuracy up to 98.584% has been obtained when using 4 samples per class for training. The experimental results demonstrate that our proposed approach is feasible and effective in biometrics.

Limited independent flexion of the thumb and fingers in human subjects.

PubMed Central

Kilbreath, S L; Gandevia, S C

1994-01-01

1. We investigated whether human subjects can activate selectively flexor pollicis longus (FPL) and digital portions of flexor digitorum profundus (FDP). These muscles were selected because they are the only flexors of the distal phalanges. 2. Electromyographic activity (EMG) was recorded with intramuscular electrodes from one digital component of the deep flexors ('test') while subjects lifted weights by flexing the distal interphalangeal joint of the other digits in turn ('lifting' digits). Only recording sites at which single motor units were recruited selectively at low forces were used. The weights lifted represented 2.5-50% of the maximal voluntary contraction (MVC). We measured the lowest weight lifted which produced phasic and tonic coactivation in the 'test' muscle. 3. The extent of coactivation varied with the 'distance' between the test and lifting digits although no significant difference occurred in the pattern of coactivation thresholds among the digital flexors. The extent of coactivation increased when angular displacement or velocity at the distal interphalangeal joint of the lifting digit increased but was not critically dependent on restraint of the hand. 4. Because mechanical 'connections' could interfere with the ability to move a distal phalanx independently, the arms of nine cadavers were studied. The separation of tendons between the thumb (FPL) and the index portion of FDP, and between the index and middle portions of FDP, usually extended more proximally in the forearm than separation between the tendons to the middle and ring fingers and between the ring and little fingers. Direct intertendinous links were also noted. 5. It is not possible to direct a sufficiently focal motor command to flex selectively the distal joint of the fingers and thumb when forces exceeding 2.5% MVC are generated. For the middle, ring and little fingers in particular, movement of adjacent digits may also involve 'in-series' mechanical links between adjacent components of FDP. Images Figure 6 PMID:7837104

Metacarpophalangeal joint arthroscopy: indications revisited.

PubMed

Choi, Alexander K Y; Chow, Esther C S; Ho, P C; Chow, Y Y

2011-08-01

Arthroscopic surgery has become the gold standard for the diagnosis and treatment of major joint disorders. With advancement in arthroscopic technique, arthroscopy has become feasible in most human joints, even those as small as the finger joints. The metacarpophalangeal joint (MCPJ) can become spacious with simple traction, the intra-articular anatomy is simple, and its major structures can be easily visualized and identified. However, MCPJ arthroscopy has never been popular. This article describes our experience with MCPJ arthroscopy and seeks to establish its role in clinical practice. Copyright © 2011 Elsevier Inc. All rights reserved.

The Lateral Proximal Phalanx Flap for Contractures and Soft Tissue Defects in the Proximal Interphalangeal Joint

PubMed Central

Beltrán, Aldo G.; Romero, Camilo J.

2016-01-01

Background: The management of contractures and soft tissue defects in the proximal interphalangeal (PIP) finger joint remains a challenge. We report a transposition flap from the lateral skin of the proximal phalanx that is based on perforating branches of the digital arteries and can be used safely for both palmar and dorsal cover defects. Methods: We first completed an anatomic study, dissecting 20 fingers in fresh cadavers with arterial injections and made the new flap in patients with dorsal or palmar defects in PIP joints. Results: In cadavers, we can reveal 4 constant branches from each digital artery in the proximal phalanx, with the more distal just in the PIP joint constituting the flap pedicle. Between February 2010 and February 2015, we designed 33 flaps in 29 patients, 7 for dorsal and 26 for palmar defects, with no instances of flap necrosis and 4 distal epidermolysis. The patients were between 4 and 69 years with no major complications, and all of the skin defects in the PIP joint were resolved satisfactorily without any relevant sequelae at the donor site. Conclusions: This flap procedure is an easy, reliable, versatile, and safe technique, and could be an important tool for the management of difficult skin defects and contractures at the PIP joint level. PMID:28082850

Transfer of supinator motor branches to the posterior interosseous nerve in C7-T1 brachial plexus palsy.

PubMed

Bertelli, Jayme Augusto; Ghizoni, Marcos Flavio

2010-07-01

In C7-T1 palsies of the brachial plexus, shoulder and elbow function are preserved, but finger motion is absent. Finger flexion has been reconstructed by tendon or nerve transfers. Finger extension has been restored ineffectively by attaching the extensor tendons to the distal aspect of the dorsal radius (termed tenodesis) or by tendon transfers. In these palsies, supinator muscle function is preserved, because innervation stems from the C-6 root. The feasibility of transferring supinator branches to the posterior interosseous nerve has been documented in a previous anatomical study. In this paper, the authors report the clinical results of supinator motor nerve transfer to the posterior interosseous nerve in 4 patients with a C7-T1 root lesion. Four adult patients with C7-T1 root lesions underwent surgery between 5 and 7 months postinjury. The patients had preserved motion of the shoulder, elbow, and wrist, but they had complete palsy of finger motion. They underwent finger flexion reconstruction via transfer of the brachialis muscle, and finger and thumb extension were restored by transferring the supinator motor branches to the posterior interosseous nerve. This nerve transfer was performed through an incision over the proximal third of the radius. Dissection was carried out between the extensor carpi radialis brevis and the extensor digitorum communis. The patients were followed up as per regular protocol and underwent a final evaluation 12 months after surgery. To document the extent of recovery, the authors assessed the degree of active metacarpophalangeal joint extension of the long fingers. The thumb span was evaluated by measuring the distance between the thumb pulp and the lateral aspect of the index finger. Surgery to transfer the supinator motor branches to the posterior interosseous nerve was straightforward. Twelve months after surgery, all patients were capable of opening their hand and could fully extend their metacarpophalangeal joints. The distance of thumb abduction improved from 0 to 5 cm from the lateral aspect of the index finger. Transferring supinator motor nerves directly to the posterior interosseous nerve is effective in at least partially restoring thumb and finger extension in patients with lower-type injuries of the brachial plexus.

Effectiveness of Conservative, Surgical, and Postsurgical Interventions for Trigger Finger, Dupuytren Disease, and De Quervain Disease: A Systematic Review.

PubMed

Huisstede, Bionka M; Gladdines, Saskia; Randsdorp, Manon S; Koes, Bart W

2017-08-30

To provide an evidence-based overview of the effectiveness of conservative and (post)surgical interventions for trigger finger, Dupuytren disease, and De Quervain disease. Cochrane Library, Physiotherapy Evidence Database, PubMed, Embase, and CINAHL were searched to identify relevant systematic reviews and randomized controlled trials (RCTs). Two reviewers independently applied the inclusion criteria to select potential studies. Two reviewers independently extracted the data and assessed the methodologic quality. A best-evidence synthesis was performed to summarize the results. Two reviews (trigger finger and De Quervain disease) and 37 randomized controlled trials (RCTs) (trigger finger: n=8; Dupuytren disease: n=14, and De Quervain disease: n=15) were included. The trials reported on oral medication (Dupuytren disease), physiotherapy (De Quervain disease), injections and surgical treatment (trigger finger, Dupuytren disease, and De Quervain disease), and other conservative (De Qervain disease) and postsurgical treatment (Dupuytren disease). Moderate evidence was found for the effect of corticosteroid injection on the very short term for trigger finger, De Quervain disease, and for injections with collagenase (30d) when looking at all joints, and no evidence was found when looking at the PIP joint for Dupuytren disease. A thumb splint as additive to a corticosteroid injection seems to be effective (moderate evidence) for De Quervain disease (short term and midterm). For Dupuytren disease, use of a corticosteroid injection within a percutaneous needle aponeurotomy in the midterm and tamoxifen versus a placebo before or after a fasciectomy seems to promising (moderate evidence). We also found moderate evidence for splinting after Dupuytren surgery in the short term. In recent years, more and more RCTs have been conducted to study treatment of the aforementioned hand disorders. However, more high-quality RCTs are still needed to further stimulate evidence-based practice for patients with trigger finger, Dupuytren disease, and De Quervain disease. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

A Novel Approach for Reconstruction of Finger Neurocutaneous Defect: A Sensory Reverse Dorsal Digital Artery Flap from the Neighboring Digit.

PubMed

Feng, Shi-Ming; Sun, Qing-Qing; Cheng, Jian; Wang, Ai-Guo

2017-11-01

Providing soft tissue coverage for finger neurocutaneous defects presents aesthetic and sensory challenges. A common source for reconstruction of soft tissue defects of the fingers is the same finger. However, when the donor areas are damaged by concomitant injuries, this option is not available. The present study aims to reconstruct finger neurocutaneous defects using a sensory reverse dorsal digital artery flap from the neighboring digit and to evaluate the efficacy of this technique. The study included 16 patients, with an average age of 34.9 years (range, 20-53 years) at the time of surgery, from May 2010 to June 2013. The sensory reverse dorsal digital artery flap was used in all 16 patients, who had a combination of soft tissue and digital nerve defects. The mean size of the soft tissue defects was 3.1 cm × 2.0 cm, and the mean flap size was 3.3 cm × 2.2 cm. The length of the nerve defects ranged from 1.3 to 2.5 cm (mean, 2.0 cm), which were reconstructed with dorsal branches of the proper digital nerve transfer. The active motion of the fingers (injured and donor) and the flap sensibility (static two-point discrimination) were measured. The appearance and functional recovery of the injured finger and the donor site were assessed using the Michigan Hand Outcomes Questionnaire. All flaps survived completely. No complications were reported, and no further flap debulking procedure was required. At the mean follow-up period of 24 months (range, 18-30 months), the mean static two-point discrimination was 6.5 mm (range, 5-10 mm) of the reconstructed area; the mean ranges of motions of the injured finger and the opposite finger at the proximal interphalangeal and distal interphalangeal joints were 102.2° and 103.5°, and 70.3° and 76.5°, respectively. The average ranges of motions of the metacarpophalangeal and proximal interphalangeal joints of the donor fingers were 90° and 103.4°, respectively. Based on the Michigan Hand Outcomes Questionnaire, 10 patients were strongly satisfied and 6 were satisfied with the functional recovery of the injured finger; however, 13 patients were strongly satisfied and 3 were satisfied with the appearance of the injured finger. The sensory reverse dorsal digital artery flap from the neighboring digit, based on the dorsal branch of the digital artery, is an effective and additional option for finger neurocutaneous defect reconstruction when use of the local and regional flaps is not feasible. © 2017 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

A pilot study to assess use of passive extension bias to facilitate finger movement for repetitive task practice after stroke.

PubMed

Iwamuro, B T; Fischer, H C; Kamper, D G

2011-01-01

The purpose of this study was to investigate whether active range of finger motion could be increased through the introduction of passive, external extension joint torques in stroke survivors. Five chronic stroke survivors with severe hand impairment resulting from hemiparesis took part in the study. Participants completed 2 experimental sessions in which hand movement and function were assessed. In one session, they wore a custom orthotic glove (X-Glove) that passively supplied extension torques to the joints of the fingers. In the second session, they performed the same tasks as in the other session, but without the glove. Outcome measures consisted of active range of motion, distance of the fingertip from the hand, selected tasks from the Graded Wolf Motor Function Test (GWMFT), and the Box and Blocks (BB) test. Primary results with and without the glove were compared using paired t tests with a Bonferroni correction. Active range of motion improved significantly by over 50%, from 4.4 cm to 6.7 cm, when the X-Glove was worn (P = .011). The distance of the fingertip from the metacarpophalangeal joint increased by an average of 2.2 cm for 4 of the subjects, although this change was not significant across all 5 subjects (P = .123). No significant differences were observed in the BB or GWMFT whether the X-Glove was worn or not. Introduction of passive extension torque can improve active range of motion for the fingers, even in chronic stroke survivors with substantial hand impairment. The increased range of motion would facilitate therapeutic training of the hand, potentially even in the home environment, although the bulk of the orthosis should be minimized to facilitate interactions with real objects.

Management of an unusual extreme extension contracture of the wrist: role of a custom-designed exercise program in achieving a good range of movement and prevention of recontraction.

PubMed

Saraiya, Hemant

2003-01-01

An extreme extension contracture of wrist with dorsal contracture of fingers 15 years after burn injury is described. Shortening of extensor tendons, secondary lengthening of flexor tendons, contracted wrist joint capsule, unusual dislocation of carpals, dorsal dislocation of metacarpophalangeal joints of fingers, and provision of sufficient amount of good-quality skin were some of the issues that had to be addressed in treatment. The contracture was released, the carpals and metacarpophalangeal joint dislocations were corrected and fixed with K wires, and the resulting defect was covered with a sheet split-thickness skin graft. An exercise program was designed that consisted of isotonic, isokinetic, and isometric resistance exercises and passive, active, and active-assistive range of motion exercises. These exercises were pursued with the intention of increasing dynamic strength, endurance, and overall functional recovery of the flexor muscles by exploiting the immature nature of early scar tissue. The resultant enhanced flexor muscle power from exercises along with the dynamic splint helped in lengthening of extensor tendons, wrist joint capsule, and split-thickness skin graft. It also helped in resisting the recontracting tendency, with further recovery of good range of wrist and fingers movements, obviating the need of tendon-lengthening surgery and flap coverage. One and half years of follow up didn't show any sign of recontracture, and the patient was able to perform his routine activities. Postburn wrist contractures of such magnitude have been seldom described. Emphasis is put on simple contracture release and a postoperative exercise program.

Treatment of mallet finger deformity with a modified palmaris longus tendon graft through a bone tunnel.

PubMed

Liu, Zengbing; Ma, Kai; Huang, Dong

2018-01-01

To investigate the clinical effect of treating mallet finger deformity using a modified palmaris longus tendon graft through a bone tunnel. Altogether, 21 patients with mallet finger deformity (16 men, 5 women; average age 31 years, range 19-47 years) were treated with a modified palmaris longus tendon graft through a bone tunnel during 18 months (2014-2016). Four index fingers, seven middle fingers, eight ring fingers, and two little fingers were treated for four cutting injuries, eleven finger sprains, four crush injuries, and two twist injuries (7 open and 14 closed injuries). Duration from injury to surgery was 9 h to 13 weeks. Three patients underwent surgery after 6 weeks of unsuccessful conservative treatment. No tendon was attached to the extensor tendon insertion in 16 patients, and 5 had residual tendon of <0.2 cm attached. All patients had distal segment flexion deformity and dorsiflexion disorder. Surgery comprised transverse penetration and vertical drilling of the base of the distal phalanx (2.0 and 2.5 mm diameter drills). Equal shallow semitendinosus pieces of the palmaris longus tendon (4 cm) were obtained from the sagittal end and were passed through a dorsal bone hole, emerging from a transverse bone hole. The two bundles were sutured to the main tendon. Tension was adjusted, and the broken ends were sutured. The distal interphalangeal joints were fixed in hyperextension. All patients were followed for 7-16 months (average 6.0 ± 0.3 months) postoperatively. All 21 patients had grade A wound healing, with no complications (e.g., necrotic wound, recurrence, joint stiffness). The mallet finger deformity was corrected with good appearance, no obvious abnormalities, and satisfactory flexion and extension. Two patients had a superficial wound infection. Each recovered after symptomatic treatment. One patient had a mild result, with limited extension. There were no recurrences. Results were evaluated according to Patel et al.'s system, which revealed 15 excellent and 5 good results (combined 95.23% rate), with 1 mild result (limited extension). Patients were satisfied with the appearance and function of the affected fingers, and the desired surgical end result was achieved. Use of this modified surgery for treating mallet finger deformity, especially with no or little tendon attached at the extensor tendon insertion, results in nearly anatomical reconstruction of the extensor tendon insertion. Its advantages include simple surgery, reliable fixation, fewer complications, and clinical efficacy.

Microscopic pick-and-place teleoperation

NASA Astrophysics Data System (ADS)

Bhatti, Pamela; Hannaford, Blake; Marbot, Pierre-Henry

1993-03-01

A three degree-of-freedom direct drive mini robot has been developed for biomedical applications. The design approach of the mini robot relies heavily upon electromechanical components from the Winchester disk drive industry. In the current design, the first joint is driven by actuators from a 5.25' drive, and the following joints are driven by actuators typical of 3.5' drives. The system has 5 - 10 micrometers of position repeatability and resolution in all three axes. A mini gripper attachment has been fabricated for the robot to explore manipulation of objects ranging from 50 micrometers to 500 micrometers . Mounted on the robot, the gripper has successfully performed pick and place operations under teleoperated control. The mini robot serves to precisely position the gripper, and a needle-like finger of the gripper deflects so the fingers can grip a target object. The gripper finger capable of motion is fabricated with a piezoelectric bimorph crystal which deflects with an applied DC voltage. The experimental results are promising, and the mini gripper may be modified for future biomedical and micro assembly applications.

Gage for evaluating rheumatoid hands

NASA Technical Reports Server (NTRS)

Houge, J. C.; Plautz, K. A.

1981-01-01

Two-axis goniometer accurately measures movements of fingers about knuckle joints, diagnosing hands structurally changed by rheumatoid arthritis. Instrument measures lateral movement which is small in normal knuckles but increased in diseased joints. Goniometer is two connected protractors that simultaneously measure angles in perpindicular planes. Dials are offset to clear bony protuberances; extension and offset adjustments span any hand size.

Anatomy and Biomechanics of the Finger Proximal Interphalangeal Joint.

PubMed

Pang, Eric Quan; Yao, Jeffrey

2018-05-01

A complete understanding of the normal anatomy and biomechanics of the proximal interphalangeal joint is critical when treating pathology of the joint as well as in the design of new reconstructive treatments. The osseous anatomy dictates the principles of motion at the proximal interphalangeal joint. Subsequently, the joint is stabilized throughout its motion by the surrounding proximal collateral ligament, accessory collateral ligament, and volar plate. The goal of this article is to review the normal anatomy and biomechanics of the proximal interphalangeal joint and its associated structures, most importantly the proper collateral ligament, accessory collateral ligament, and volar plate. Copyright © 2017 Elsevier Inc. All rights reserved.

Visual and computer software-aided estimates of Dupuytren's contractures: correlation with clinical goniometric measurements.

PubMed

Smith, R P; Dias, J J; Ullah, A; Bhowal, B

2009-05-01

Corrective surgery for Dupuytren's disease represents a significant proportion of a hand surgeon's workload. The decision to go ahead with surgery and the success of surgery requires measuring the degree of contracture of the diseased finger(s). This is performed in clinic with a goniometer, pre- and postoperatively. Monitoring the recurrence of the contracture can inform on surgical outcome, research and audit. We compared visual and computer software-aided estimation of Dupuytren's contractures to clinical goniometric measurements in 60 patients with Dupuytren's disease. Patients' hands were digitally photographed. There were 76 contracted finger joints--70 proximal interphalangeal joints and six distal interphalangeal joints. The degrees of contracture of these images were visually assessed by six orthopaedic staff of differing seniority and re-assessed with computer software. Across assessors, the Pearson correlation between the goniometric measurements and the visual estimations was 0.83 and this significantly improved to 0.88 with computer software. Reliability with intra-class correlations achieved 0.78 and 0.92 for the visual and computer-aided estimations, respectively, and with test-retest analysis, 0.92 for visual estimation and 0.95 for computer-aided measurements. Visual estimations of Dupuytren's contractures correlate well with actual clinical goniometric measurements and improve further if measured with computer software. Digital images permit monitoring of contracture after surgery and may facilitate research into disease progression and auditing of surgical technique.

Dislocation

MedlinePlus

... Dislocations can occur in contact sports, such as football and hockey, and in sports in which falls ... downhill skiing, gymnastics and volleyball. Basketball players and football players also commonly dislocate joints in their fingers ...

Bulimia

MedlinePlus

... large amounts of high-calorie foods, usually in secret. During these episodes, the person feels a lack ... and pimples Small cuts and calluses across the tops of the finger joints from forcing oneself to ...

Design of a wearable hand exoskeleton for exercising flexion/extension of the fingers.

PubMed

Jo, Inseong; Lee, Jeongsoo; Park, Yeongyu; Bae, Joonbum

2017-07-01

In this paper, design of a wearable hand exoskeleton system for exercising flexion/extension of the fingers, is proposed. The exoskeleton was designed with a simple and wearable structure to aid finger motions in 1 degree of freedom (DOF). A hand grasping experiment by fully-abled people was performed to investigate general hand flexion/extension motions and the polynomial curve of general hand motions was obtained. To customize the hand exoskeleton for the user, the polynomial curve was adjusted to the joint range of motion (ROM) of the user and the optimal design of the exoskeleton structure was obtained using the optimization algorithm. A prototype divided into two parts (one part for the thumb, the other for rest fingers) was actuated by only two linear motors for compact size and light weight.

Morphology and Mobility of the Reconstructed Basilar Joint of the Pollicized Index Finger.

PubMed

Strugarek-Lecoanet, Clotilde; Chevrollier, Jérémie; Pauchard, Nicolas; Blum, Alain; Dap, François; Dautel, Gilles

2016-09-01

To evaluate outcome and function of the reconstructed basilar thumb joint after index finger pollicization in patients presenting congenital thumb deficiency. Plain radiographs and 4-dimensional dynamic volume computed tomography scan were used to evaluate the outcome of 23 pollicizations performed on 14 children between 1996 and 2009. The mean follow-up was 8 years. Patients performed continuous movements of thumb opposition during the imaging studies. Four-dimensional scan images made it possible to visualize mobility within the reconstructed joint. In 14 cases, union occurred in the metacarpal head/metacarpal base interface. In the 9 other cases, there was a nonunion at this interface. The reconstructed joint was mobile in 20 cases, including 3 in which there was also mobility at the site of the nonunion. In 3 cases in our series, mobility was present only at the site of the nonunion, between the base and the head of the second metacarpal. Remodeling and flattening out of the metacarpal head occurred in 16 of 23 cases. The transposed metacarpal head remained spherical in 7 cases. The reconstructed joint adapts, both morphologically and functionally, allowing movement on all 3 spatial planes. Existing mechanical constraints on the reconstructed joint may explain its remodeled appearance. Therapeutic IV. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

The Lateral Proximal Phalanx Flap for Contractures and Soft Tissue Defects in the Proximal Interphalangeal Joint: An Anatomical and Clinical Study.

PubMed

Beltrán, Aldo G; Romero, Camilo J

2017-01-01

Background: The management of contractures and soft tissue defects in the proximal interphalangeal (PIP) finger joint remains a challenge. We report a transposition flap from the lateral skin of the proximal phalanx that is based on perforating branches of the digital arteries and can be used safely for both palmar and dorsal cover defects. Methods: We first completed an anatomic study, dissecting 20 fingers in fresh cadavers with arterial injections and made the new flap in patients with dorsal or palmar defects in PIP joints. Results: In cadavers, we can reveal 4 constant branches from each digital artery in the proximal phalanx, with the more distal just in the PIP joint constituting the flap pedicle. Between February 2010 and February 2015, we designed 33 flaps in 29 patients, 7 for dorsal and 26 for palmar defects, with no instances of flap necrosis and 4 distal epidermolysis. The patients were between 4 and 69 years with no major complications, and all of the skin defects in the PIP joint were resolved satisfactorily without any relevant sequelae at the donor site. Conclusions: This flap procedure is an easy, reliable, versatile, and safe technique, and could be an important tool for the management of difficult skin defects and contractures at the PIP joint level.

Selection of optimal multispectral imaging system parameters for small joint arthritis detection

NASA Astrophysics Data System (ADS)

Dolenec, Rok; Laistler, Elmar; Stergar, Jost; Milanic, Matija

2018-02-01

Early detection and treatment of arthritis is essential for a successful outcome of the treatment, but it has proven to be very challenging with existing diagnostic methods. Novel methods based on the optical imaging of the affected joints are becoming an attractive alternative. A non-contact multispectral imaging (MSI) system for imaging of small joints of human hands and feet is being developed. In this work, a numerical simulation of the MSI system is presented. The purpose of the simulation is to determine the optimal design parameters. Inflamed and unaffected human joint models were constructed with a realistic geometry and tissue distributions, based on a MRI scan of a human finger with a spatial resolution of 0.2 mm. The light transport simulation is based on a weighted-photon 3D Monte Carlo method utilizing CUDA GPU acceleration. An uniform illumination of the finger within the 400-1100 nm spectral range was simulated and the photons exiting the joint were recorded using different acceptance angles. From the obtained reflectance and transmittance images the spectral and spatial features most indicative of inflammation were identified. Optimal acceptance angle and spectral bands were determined. This study demonstrates that proper selection of MSI system parameters critically affects ability of a MSI system to discriminate the unaffected and inflamed joints. The presented system design optimization approach could be applied to other pathologies.

Balancing a force on the fingertip of a two-dimensional finger model without intrinsic muscles.

PubMed

Spoor, C W

1983-01-01

A slightly flexed human middle finger can balance an external force on the fingertip. Internal stabilization is also possible, which means that the externally unloaded finger can be kept stiff. We want to analyse whether in these situations the intrinsic hand muscles are needed. Distances from tendons to flexion axes are taken from the literature and are substituted in the moment equilibrium equations of a two-dimensional finger model. Diagrams illustrate the statically indeterminate problem of solving tendon forces. The possibilities for equilibrium without intrinsics appear to depend mainly on four tendon-to-joint distances. These distances determine to which of two groups a finger belongs: (1) one in which intrinsics are not necessary for internal stabilization nor for balancing a force on the fingertip in any direction in the sagittal plane; (2) one in which, without intrinsics, internal stabilization is impossible and only dorso-distally directed forces on the fingertip can be balanced.

Medial Elbow Joint Space Increases With Valgus Stress and Decreases When Cued to Perform A Maximal Grip Contraction.

PubMed

Pexa, Brett S; Ryan, Eric D; Myers, Joseph B

2018-04-01

Previous research indicates that the amount of valgus torque placed on the elbow joint during overhead throwing is higher than the medial ulnar collateral ligament (UCL) can tolerate. Wrist and finger flexor muscle activity is hypothesized to make up for this difference, and in vitro studies that simulated activity of upper extremity musculature, specifically the flexor digitorum superficialis and flexor carpi ulnaris, support this hypothesis. To assess the medial elbow joint space at rest, under valgus stress, and under valgus stress with finger and forearm flexor contraction by use of ultrasonography in vivo. Controlled laboratory study. Participants were 22 healthy males with no history of elbow dislocation or UCL injury (age, 21.25 ± 1.58 years; height, 1.80 ± 0.08 m; weight, 79.43 ± 18.50 kg). Medial elbow joint space was measured by use of ultrasonography during 3 separate conditions: at rest (unloaded), under valgus load (loaded), and with a maximal grip contraction under a valgus load (loaded-contracted) in both limbs. Participants lay supine with their arm abducted 90° and elbow flexed 30° with the forearm in full supination. A handgrip dynamometer was placed in the participants' hand to grip against during the contracted condition. Images were reduced in ImageJ to assess medial elbow joint space. A 2-way (condition × limb) repeated-measures analysis of variance and Cohen's d effect sizes were used to assess changes in medial elbow joint space. Post hoc testing was performed with a Bonferroni adjustment to assess changes within limb and condition. The medial elbow joint space was significantly larger in the loaded condition (4.91 ± 1.16 mm) compared with the unloaded condition (4.26 ± 1.23 mm, P < .001, d = 0.712) and the loaded-contracted condition (3.88 ± 0.94 mm, P < .001, d = 1.149). No significant change was found between the unloaded and loaded-contracted conditions ( P = .137). Medial elbow joint space increases under a valgus load and then decreases when a maximal grip contraction is performed. This indicates that wrist and finger flexor muscle contraction may assist in limiting medial elbow joint space, a result similar to findings of previous research in vitro. Muscle activation of the upper extremity limits the medial elbow joint space, suggesting that injury prevention programs for throwing athletes should incorporate exercises for the elbow, wrist, and hand to limit excessive medial elbow joint space gapping during activities that create high valgus load.

Effect of adhesive stiffness and thickness on stress distributions in structural finger joints

Treesearch

Leslie H. Groom; Robert J. Leichti

1994-01-01

Environmental, political. and socioeconomic actions over the past several years have resulted in a decreased wood supply at a time when there is an increased demand for forest products. This combination of increased demand and decreased supply has forced more emphasis on engineered wood products, a varied category usually connected with adhesively-bonded end joints, of...

Effect of adhesive stiffness and thickness on stress distributions in structural finger joints

Treesearch

Leslie H. Groom; Robert J. Leichti

1994-01-01

Environmental, political, and socioeconomic actions over the past several years have resulted in a decreased wood supply at a time when there is an increased demand for forest products. This combination of increased demand and decreased supply has forced more emphasis on engineered wood products, a varied category usually connected with adhesively-bonded end joints, of...

Embodiment and Manipulation Learning Process for a Humanoid Hand.

DTIC Science & Technology

1995-05-01

Figures 1-1 Human somatotopic mappings 16 1-2 Human anatomy terminology 18 2-1 A picture of Cog 24 2-2 A picture of Cog’s hand 27 3-1 A... human anatomy terminologies shown in Figure 1-2 [24]. The mechanical hand constructed for this thesis have three fingers, each having two segments...and two joints, and a thumb with one segment and a joint, so the terms 18 CHAPTER 1. INTRODUCTION Saddle-joint of the thumb Figure 1-2: Human

Experience of Soviet Medicine in a Great Patriotic War, 1941-1945. Volume 16, Section 4.

DTIC Science & Technology

1980-10-22

Rotor function in the elbow, wrist joint and in the fingers/pins. In spite of energetic treatment by physiotherapy and therapeutic gymnastics , remained...the radiocarpal and elbow joint is removed by therapeutic gymnastics . It is discharged after 84 days (4/11 1943) with a good anatomical and functional...military service, it returned home into Moscow. on the arrival into nosco knee joint did not fold. Injured person itself dealt by gymnastics and in a

Erbium--169 versus triamcinolone hexacetonide in the treatment of rheumatoid finger joints.

PubMed Central

Ruotsi, A; Hypén, M; Rekonen, A; Oka, M

1979-01-01

Erbium--169 was compared with triamcinolone hexacetonide in the topical treatment of 32 patients suffering from rheumatoid arthritis. Erbium--169 was injected into 83 and triamcinolone hexacetonide into 54 proximal interphalangeal or metacarpophalangeal joints. Both treatments produced alleviation of joint pain and swelling and improvement of grip strength. At every check-up (1--18 months) the percentage of remissions was higher after triamcinolone hexacetonide injection than after erbium--169. The difference was significant at 1, 3, and 6 months. PMID:434946

The joint Simon effect depends on perceived agency, but not intentionality, of the alternative action

PubMed Central

Stenzel, Anna; Dolk, Thomas; Colzato, Lorenza S.; Sellaro, Roberta; Hommel, Bernhard; Liepelt, Roman

2014-01-01

A co-actor's intentionality has been suggested to be a key modulating factor for joint action effects like the joint Simon effect (JSE). However, in previous studies intentionality has often been confounded with agency defined as perceiving the initiator of an action as being the causal source of the action. The aim of the present study was to disentangle the role of agency and intentionality as modulating factors of the JSE. In Experiment 1, participants performed a joint go/nogo Simon task next to a co-actor who either intentionally controlled a response button with own finger movements (agency+/intentionality+) or who passively placed the hand on a response button that moved up and down on its own as triggered by computer signals (agency−/intentionality−). In Experiment 2, we included a condition in which participants believed that the co-actor intentionally controlled the response button with a Brain-Computer Interface (BCI) while placing the response finger clearly besides the response button, so that the causal relationship between agent and action effect was perceptually disrupted (agency−/intentionality+). As a control condition, the response button was computer controlled while the co-actor placed the response finger besides the response button (agency−/intentionality−). Experiment 1 showed that the JSE is present with an intentional co-actor and causality between co-actor and action effect, but absent with an unintentional co-actor and a lack of causality between co-actor and action effect. Experiment 2 showed that the JSE is absent with an intentional co-actor, but no causality between co-actor and action effect. Our findings indicate an important role of the co-actor's agency for the JSE. They also suggest that the attribution of agency has a strong perceptual basis. PMID:25140144

The joint Simon effect depends on perceived agency, but not intentionality, of the alternative action.

PubMed

Stenzel, Anna; Dolk, Thomas; Colzato, Lorenza S; Sellaro, Roberta; Hommel, Bernhard; Liepelt, Roman

2014-01-01

A co-actor's intentionality has been suggested to be a key modulating factor for joint action effects like the joint Simon effect (JSE). However, in previous studies intentionality has often been confounded with agency defined as perceiving the initiator of an action as being the causal source of the action. The aim of the present study was to disentangle the role of agency and intentionality as modulating factors of the JSE. In Experiment 1, participants performed a joint go/nogo Simon task next to a co-actor who either intentionally controlled a response button with own finger movements (agency+/intentionality+) or who passively placed the hand on a response button that moved up and down on its own as triggered by computer signals (agency-/intentionality-). In Experiment 2, we included a condition in which participants believed that the co-actor intentionally controlled the response button with a Brain-Computer Interface (BCI) while placing the response finger clearly besides the response button, so that the causal relationship between agent and action effect was perceptually disrupted (agency-/intentionality+). As a control condition, the response button was computer controlled while the co-actor placed the response finger besides the response button (agency-/intentionality-). Experiment 1 showed that the JSE is present with an intentional co-actor and causality between co-actor and action effect, but absent with an unintentional co-actor and a lack of causality between co-actor and action effect. Experiment 2 showed that the JSE is absent with an intentional co-actor, but no causality between co-actor and action effect. Our findings indicate an important role of the co-actor's agency for the JSE. They also suggest that the attribution of agency has a strong perceptual basis.

Interdependency of the maximum range of flexion-extension of hand metacarpophalangeal joints.

PubMed

Gracia-Ibáñez, V; Vergara, M; Sancho-Bru, J-L

2016-12-01

Mobility of the fingers metacarpophalangeal (MCP) joints depends on the posture of the adjacent ones. Current Biomechanical hand models consider fixed ranges of movement at joints, regardless of the posture, thus allowing for non-realistic postures, generating wrong results in reach studies and forward dynamic analyses. This study provides data for more realistic hand models. The maximum voluntary extension (MVE) and flexion (MVF) of different combinations of MCP joints were measured covering their range of motion. Dependency of the MVF and MVE on the posture of the adjacent MCP joints was confirmed and mathematical models obtained through regression analyses (RMSE 7.7°).

Power Doppler sonography and pulse-inversion harmonic imaging in evaluation of rheumatoid arthritis synovitis.

PubMed

Schueller-Weidekamm, Claudia; Krestan, Christian; Schueller, Gerd; Kapral, Theresa; Aletaha, Daniel; Kainberger, Franz

2007-02-01

This study evaluates the value of contrast-enhanced pulse-inversion harmonic imaging (PIHI) to detect synovial vascularization and thus the therapeutic effects of prednisolone treatment on the inflammation in finger joints in rheumatoid arthritis (RA). Before and after 7 days of mid- to high-dose steroid therapy, blood tests and clinical and sonographic examinations were assessed in 14 patients. Two hundred eighty finger joints (metacarpophalangeal [MCP] I-V, interphalangeal [IP], and proximal interphalangeal [PIP] II-V) were investigated on power Doppler sonography to determine, in each patient, the finger joint with the strongest hypervascularization and to score the synovial vascularization. Further dynamic examination of the selected joint was performed on PIHI after i.v. administration of a second-generation sonographic contrast medium. Vascularization was quantified by calculating the area under the time-intensity curves. The changes in signal intensities before and after therapy were correlated with clinical examinations (disease activity score [DAS]). The score of the joint with the strongest hypervascularization assessed by power Doppler sonography decreased significantly from 1.7 to 1.3 (p < 0.01); however, in six patients, no change was assessed after steroid therapy. In all patients, a significant reduction in PIHI signals was observed after therapy (p < 0.05). The baseline and follow-up median values of the area under the time-intensity curves were 8.56 +/- 1.28 and 7.65 +/- 0.66, respectively. The median values of the DAS decreased significantly from 4.90 +/- 0.86 to 3.6 +/- 1.0 (p < 0.01) 7 days after the steroid therapy. PIHI and power Doppler sonography enable the detection of synovial perfusion alterations after steroid therapy and, therefore, may be useful tools for the evaluation of active inflammation in RA and for the assessment of therapeutic response. However, minor changes of synovial vascularization can be better detected on PIHI than on power Doppler sonography.

Crooked fingers and sparse hair: an interesting case of trichorhinophalangeal syndrome type 1.

PubMed

Narayanan, Ramakrishna; Chennareddy, Srinivasa

2015-01-27

Trichorhinophalangeal syndrome type 1 is a rare skeletal dysplasia of autosomal-dominant inheritance due to defects in the TRPS-1 gene. The syndrome is characterised by sparse slow-growing hair, a bulbous pear-shaped nose, cone-shaped epiphyses and deformities of the interphalangeal joints resembling those in rheumatoid arthritis. We present a case of trichorhinophalangeal syndrome in a 23-year-old man who presented with symmetrical painless progressive deformity of the fingers in both hands. 2015 BMJ Publishing Group Ltd.

Modernization of the Air Expeditionary Squadron AMAL 0960

DTIC Science & Technology

2012-07-25

to other organism not classified 1 682.9 Cellulitis and abscess of unspecified parts 2 078.1 Viral warts 1 719.41 Pain in joint shoulder 3...and strains of sacroiliac region 1 611.7 Breast lump 1 847.2 Sprain lumbar region 1 681 Cellulitis and abscess of finger and toe 2 873.4 Open...wound of face without mention of complication 1 682.6 Cellulitis and abscess of leg except foot 1 883.0 Open wound of fingers without

Grasp planning under uncertainty

NASA Technical Reports Server (NTRS)

Erkmen, A. M.; Stephanou, H. E.

1989-01-01

The planning of dexterous grasps for multifingered robot hands operating in uncertain environments is covered. A sensor-based approach to the planning of a reach path prior to grasping is first described. An on-line, joint space finger path planning algorithm for the enclose phase of grasping was then developed. The algorithm minimizes the impact momentum of the hand. It uses a Preshape Jacobian matrix to map task-level hand preshape requirements into kinematic constraints. A master slave scheme avoids inter-finger collisions and reduces the dimensionality of the planning problem.

Reduced servo-control of fatigued human finger extensor and flexor muscles.

PubMed Central

Hagbarth, K E; Bongiovanni, L G; Nordin, M

1995-01-01

1. In healthy human subjects holding the index finger semi-extended at the metacarpophalangeal joint against a moderate load, electromyographic (EMG) activity was recorded from the finger extensor and flexor muscles during different stages of muscle fatigue. The aim was to study the effect of muscle fatigue on the level of background EMG activity and on the reflex responses to torque pulses causing sudden extensor unloadings. Paired comparisons were made between the averaged EMG and finger deflection responses under two conditions: (1) at a stage of fatigue (following a sustained co-contraction) when great effort was required to maintain the finger position, and (2) under non-fatigue conditions while the subject tried to produce similar background EMG levels to those in the corresponding fatigue trials. 2. Both the unloading reflex in the extensor and the concurrent stretch reflex in the flexor were significantly less pronounced and had a longer latency in the fatigue trials. Consequently, the finger deflections had a larger amplitude and were arrested later in the fatigue trials. 3. It is concluded that--with avoidance of 'automatic gain compensation', i.e. reflex modifications attributable to differences in background EMG levels--the servo-like action of the unloading and stretch reflexes is reduced in fatigued finger extensor and flexor muscles. PMID:7562624

3-T direct MR arthrography of the wrist: value of finger trap distraction to assess intrinsic ligament and triangular fibrocartilage complex tears.

PubMed

Cerny, Milena; Marlois, Romain; Theumann, Nicolas; Bollmann, Christof; Wehrli, Laurent; Richarme, Delphine; Meuli, Reto; Becce, Fabio

2013-10-01

To determine the value of applying finger trap distraction during direct MR arthrography of the wrist to assess intrinsic ligament and triangular fibrocartilage complex (TFCC) tears. Twenty consecutive patients were prospectively investigated by three-compartment wrist MR arthrography. Imaging was performed with 3-T scanners using a three-dimensional isotropic (0.4 mm) T1-weighted gradient-recalled echo sequence, with and without finger trap distraction (4 kg). In a blind and independent fashion, two musculoskeletal radiologists measured the width of the scapholunate (SL), lunotriquetral (LT) and ulna-TFC (UTFC) joint spaces. They evaluated the amount of contrast medium within these spaces using a four-point scale, and assessed SL, LT and TFCC tears, as well as the disruption of Gilula's carpal arcs. With finger trap distraction, both readers found a significant increase in width of the SL space (mean Δ = +0.1mm, p ≤ 0.040), and noticed more contrast medium therein (p ≤ 0.035). In contrast, the differences in width of the LT (mean Δ = +0.1 mm, p ≥ 0.057) and UTFC (mean Δ = 0mm, p ≥ 0.728) spaces, as well as the amount of contrast material within these spaces were not statistically significant (p = 0.607 and ≥ 0.157, respectively). Both readers detected more SL (Δ = +1, p = 0.157) and LT (Δ = +2, p = 0.223) tears, although statistical significance was not reached, and Gilula's carpal arcs were more frequently disrupted during finger trap distraction (Δ = +5, p = 0.025). The application of finger trap distraction during direct wrist MR arthrography may enhance both detection and characterisation of SL and LT ligament tears by widening the SL space and increasing the amount of contrast within the SL and LT joint spaces. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Sensing and Force-Feedback Exoskeleton (SAFE) Robotic Glove.

PubMed

Ben-Tzvi, Pinhas; Ma, Zhou

2015-11-01

This paper presents the design, implementation and experimental validation of a novel robotic haptic exoskeleton device to measure the user's hand motion and assist hand motion while remaining portable and lightweight. The device consists of a five-finger mechanism actuated with miniature DC motors through antagonistically routed cables at each finger, which act as both active and passive force actuators. The SAFE Glove is a wireless and self-contained mechatronic system that mounts over the dorsum of a bare hand and provides haptic force feedback to each finger. The glove is adaptable to a wide variety of finger sizes without constraining the range of motion. This makes it possible to accurately and comfortably track the complex motion of the finger and thumb joints associated with common movements of hand functions, including grip and release patterns. The glove can be wirelessly linked to a computer for displaying and recording the hand status through 3D Graphical User Interface (GUI) in real-time. The experimental results demonstrate that the SAFE Glove is capable of reliably modeling hand kinematics, measuring finger motion and assisting hand grasping motion. Simulation and experimental results show the potential of the proposed system in rehabilitation therapy and virtual reality applications.

Validation of hand and foot anatomical feature measurements from smartphone images

NASA Astrophysics Data System (ADS)

Amini, Mohammad; Vasefi, Fartash; MacKinnon, Nicholas

2018-02-01

A smartphone mobile medical application, previously presented as a tool for individuals with hand arthritis to assess and monitor the progress of their disease, has been modified and expanded to include extraction of anatomical features from the hand (joint/finger width, and angulation) and foot (length, width, big toe angle, and arch height index) from smartphone camera images. Image processing algorithms and automated measurements were validated by performing tests on digital hand models, rigid plastic hand models, and real human hands and feet to determine accuracy and reproducibility compared to conventional measurement tools such as calipers, rulers, and goniometers. The mobile application was able to provide finger joint width measurements with accuracy better than 0.34 (+/-0.25) millimeters. Joint angulation measurement accuracy was better than 0.50 (+/-0.45) degrees. The automatically calculated foot length accuracy was 1.20 (+/-1.27) millimeters and the foot width accuracy was 1.93 (+/-1.92) millimeters. Hallux valgus angle (used in assessing bunions) accuracy was 1.30 (+/-1.29) degrees. Arch height index (AHI) measurements had an accuracy of 0.02 (+/-0.01). Combined with in-app documentation of symptoms, treatment, and lifestyle factors, the anatomical feature measurements can be used by both healthcare professionals and manufacturers. Applications include: diagnosing hand osteoarthritis; providing custom finger splint measurements; providing compression glove measurements for burn and lymphedema patients; determining foot dimensions for custom shoe sizing, insoles, orthotics, or foot splints; and assessing arch height index and bunion treatment effectiveness.

Coregistered photoacoustic and ultrasound tomography of healthy and inflamed human interphalangeal joints

NASA Astrophysics Data System (ADS)

van Es, Peter; Vlieg, Redmar C.; Biswas, Samir K.; Hondebrink, Erwin; van Hespen, Johan C. G.; Moens, Hein B. J.; Steenbergen, Wiendelt; Manohar, Srirang

2015-07-01

Photoacoustic (PA) or optoacoustic (OA) imaging combines the high (blood) contrast to light with the high-resolution of ultrasound. The method can visualize vascularization deep inside tissue. Of late there is interest in PA imaging of synovial joints which are expected to be associated with increased vascularization in the event of rheumatoid arthritis (RA). We here describe our approach in investigating the application of the PA technique in arthritis. We are developing a CT-geometry version PA finger imager, intended for early clinical assessment of the method. The imager uses two curved array ultrasound detectors each with 64 elements with central frequencies 1.5 and 7.5 MHz respectively, stacked above each other. Both cover approximately 180 degrees of the circle. Illumination is provided with a multiple of optical fiber bundles coupled to a laser-OPO system. Ultrasound imaging is also possible with the system, since the curved arrays are each provided with 12 or 8 ultrasound pulsers. We have investigated systematically imaging of finger vasculature in healthy volunteers using an earlier laboratory prototype. In this paper we present finger imaging results of a patient diagnosed with rheumatoid arthritis.

Biomechanical loading on the upper extremity increases from single key tapping to directional tapping.

PubMed

Qin, Jin; Trudeau, Matthieu; Katz, Jeffrey N; Buchholz, Bryan; Dennerlein, Jack T

2011-08-01

Musculoskeletal disorders associated with computer use span the joints of the upper extremity. Computing typically involves tapping in multiple directions. Thus, we sought to describe the loading on the finger, wrist, elbow and shoulder joints in terms of kinematic and kinetic difference across single key switch tapping to directional tapping on multiple keys. An experiment with repeated measures design was conducted. Six subjects tapped with their right index finger on a stand-alone number keypad placed horizontally in three conditions: (1) on single key switch (the number key 5); (2) left and right on number key 4 and 6; (3) top and bottom on number key 8 and 2. A force-torque transducer underneath the keypad measured the fingertip force. An active-marker infrared motion analysis system measured the kinematics of the fingertip, hand, forearm, upper arm and torso. Joint moments for the metacarpophalangeal, wrist, elbow, and shoulder joints were estimated using inverse dynamics. Tapping in the top-bottom orientation introduced the largest biomechanical loading on the upper extremity especially for the proximal joint, followed by tapping in the left-right orientation, and the lowest loading was observed during single key switch tapping. Directional tapping on average increased the fingertip force, joint excursion, and peak-to-peak joint torque by 45%, 190% and 55%, respectively. Identifying the biomechanical loading patterns associated with these fundamental movements of keying improves the understanding of the risks of upper extremity musculoskeletal disorders for computer keyboard users. Copyright © 2010 Elsevier Ltd. All rights reserved.

Toward development of mobile application for hand arthritis screening.

PubMed

Akhbardeh, Farhad; Vasefi, Fartash; Tavakolian, Kouhyar; Bradley, David; Fazel-Rezai, Reza

2015-01-01

Arthritis is one of the most common health problems affecting people throughout the world. The goal of the work presented in this paper is to provide individuals, who may be developing or have developed arthritis, with a mobile application to assess and monitor the progress of their disease using their smartphone. The image processing algorithm includes finger border detection algorithm to monitor joint thickness and angular deviation abnormalities, which are common symptoms of arthritis. In this work, we have analyzed and compared gradient, thresholding and Canny algorithms for border detection. The effect of image spatial resolution (down-sampling) is also investigated. The results calculated based on 36 joint measurements show that the mean errors for gradient, thresholding, and Canny methods are 0.20, 2.13, and 2.03 mm, respectively. In addition, the average error for different image resolutions is analyzed and the minimum required resolution is determined for each method. The results confirm that recent smartphone imaging capabilities can provide enough accuracy for hand border detection and finger joint analysis based on gradient method.

Design and Characterization of a Soft Robotic Therapeutic Glove for Rheumatoid Arthritis.

PubMed

Chua, Matthew Chin Heng; Lim, Jeong Hoon; Yeow, Raye Chen Hua

2017-07-27

The modeling and experimentation of a pneumatic actuation system for the development of a soft robotic therapeutic glove is proposed in this article for the prevention of finger deformities in rheumatoid arthritis (RA) patients. The Rehabilitative Arthritis Glove (RA-Glove) is a soft robotic glove fitted with two internal inflatable actuators for lateral compression and massage of the fingers and their joints. Two mechanical models to predict the indentation and bending characteristics of the inflatable actuators based on their geometrical parameters will be presented and validated with experimental results. Experimental validation shows that the model was within a standard deviation of the experimental mean for input pressure range of 0 to 2 bars. Evaluation of the RA-Glove was also performed on six healthy human subjects. The stress distribution along the fingers of the subjects using the RA-Glove was also shown to be even and specific to the finger sizes. This article demonstrates the modeling of soft pneumatic actuators and highlights the potential of the RA-Glove as a therapeutic device for the prevention of arthritic deformities of the fingers.

Development of reaching during mid-childhood from a Developmental Systems perspective.

PubMed

Golenia, Laura; Schoemaker, Marina M; Otten, Egbert; Mouton, Leonora J; Bongers, Raoul M

2018-01-01

Inspired by the Developmental Systems perspective, we studied the development of reaching during mid-childhood (5-10 years of age) not just at the performance level (i.e., endpoint movements), as commonly done in earlier studies, but also at the joint angle level. Because the endpoint position (i.e., the tip of the index finger) at the reaching target can be achieved with multiple joint angle combinations, we partitioned variability in joint angles over trials into variability that does not (goal-equivalent variability, GEV) and that does (non-goal-equivalent variability, NGEV) influence the endpoint position, using the Uncontrolled Manifold method. Quantifying this structure in joint angle variability allowed us to examine whether and how spatial variability of the endpoint at the reaching target is related to variability in joint angles and how this changes over development. 6-, 8- and 10-year-old children and young adults performed reaching movements to a target with the index finger. Polynomial trend analysis revealed a linear and a quadratic decreasing trend for the variable error. Linear decreasing and cubic trends were found for joint angle standard deviations at movement end. GEV and NGEV decreased gradually with age, but interestingly, the decrease of GEV was steeper than the decrease of NGEV, showing that the different parts of the joint angle variability changed differently over age. We interpreted these changes in the structure of variability as indicating changes over age in exploration for synergies (a family of task solutions), a concept that links the performance level with the joint angle level. Our results suggest changes in the search for synergies during mid-childhood development.

The 1990-1991 project summaries

NASA Technical Reports Server (NTRS)

1991-01-01

Georgia Tech's School of Textile & Fiber Engineering and School of Mechanical Engineering participated in four cooperative design efforts this year. One group designed a thermal shield for a lunar telescope. The second group designed a selenotextile habitat shielding structure. The third group designed a pneumatically assisted elbow joint for the NASA zero-prebreathe suit (ZPS). The final group designed an electromechanical system to power an astronaut's finger joints. Summaries of these projects are presented.

The 1990-1991 project summaries

NASA Astrophysics Data System (ADS)

Georgia Tech's School of Textile & Fiber Engineering and School of Mechanical Engineering participated in four cooperative design efforts this year. One group designed a thermal shield for a lunar telescope. The second group designed a selenotextile habitat shielding structure. The third group designed a pneumatically assisted elbow joint for the NASA zero-prebreathe suit (ZPS). The final group designed an electromechanical system to power an astronaut's finger joints. Summaries of these projects are presented.

Further delineation of Nevo syndrome.

PubMed Central

al-Gazali, L I; Bakalinova, D; Varady, E; Scorer, J; Nork, M

1997-01-01

Nevo syndrome is an autosomal recessive syndrome characterised by prenatal overgrowth, joint laxity, kyphosis, wrist drop, spindle shaped fingers, and volar oedema. Four children from two families have been reported previously. We report two further children from two unrelated Arab families from two different tribes. Both presented at birth with hypotonia, joint laxity, kyphosis, wrist drop, spindle shaped fingers, and volar oedema. Both have delayed motor development at the ages of 2 years 10 months and 3 months respectively. Cognitive development is normal in one, and the other case appears to be developing normally at 3 months of age. One has, in addition, a wide spinal canal on MRI of the spine indicating some degree of dural ectasia. This report brings the total number of children reported with this syndrome to six from four families; three of these families are Arab. This indicates that the gene for this syndrome is probably commoner in Arabs than in other populations. Images PMID:9152832

Optical tomographic detection of rheumatoid arthritis with computer-aided classification schemes

NASA Astrophysics Data System (ADS)

Klose, Christian D.; Klose, Alexander D.; Netz, Uwe; Beuthan, Jürgen; Hielscher, Andreas H.

2009-02-01

A recent research study has shown that combining multiple parameters, drawn from optical tomographic images, leads to better classification results to identifying human finger joints that are affected or not affected by rheumatic arthritis RA. Building up on the research findings of the previous study, this article presents an advanced computer-aided classification approach for interpreting optical image data to detect RA in finger joints. Additional data are used including, for example, maximum and minimum values of the absorption coefficient as well as their ratios and image variances. Classification performances obtained by the proposed method were evaluated in terms of sensitivity, specificity, Youden index and area under the curve AUC. Results were compared to different benchmarks ("gold standard"): magnet resonance, ultrasound and clinical evaluation. Maximum accuracies (AUC=0.88) were reached when combining minimum/maximum-ratios and image variances and using ultrasound as gold standard.

Investigation of an alleged mechanism of finger injury in an automobile crash.

PubMed

Stacey, Stephen; Kent, Richard

2006-07-01

This investigation centers on the case of an adult male whose finger was allegedly amputated by the steering wheel of his car during a crash. The subject claimed to have been driving with his left index finger inserted through a hole in the spoke of his steering wheel and was subsequently involved in an offset frontal collision with a tree. The finger was found to be cleanly severed at the mid-shaft of the proximal phalanx after the crash. This injury was alleged to have been caused by inertial loading from the rotation of the steering wheel during the crash. To determine whether this injury mechanism was plausible, three laboratory tests representing distinct loading scenarios were carried out with postmortem human surrogates loaded dynamically by the subject's steering wheel. It was found that the inertial loads generated in this loading scenario are insufficient to amputate the finger. Additionally, artificially constraining the finger to force an amputation to occur revealed that a separation at the proximal interphalangeal joint occurs rather than a bony fracture of the proximal phalanx. Based on these biomechanical tests, it can be concluded that the subject's injury did not occur during the automobile crash in question. Furthermore, it can be shown that the injury was self-inflicted to fraudulently claim on an insurance policy.

Development of anthropomorphic robotic hand driven by Pneumatic Artificial Muscles for robotic applications

NASA Astrophysics Data System (ADS)

Farag, Mohannad; Zainul Azlan, Norsinnira; Hayyan Alsibai, Mohammed

2018-04-01

This paper presents the design and fabrication of a three-fingered anthropomorphic robotic hand. The fingers are driven by tendons and actuated by human muscle-like actuators known as Pneumatic Artificial Muscle (PAM). The proposed design allows the actuators to be mounted outside the hand where each finger can be driven by one PAM actuator and six indirectly interlinked tendons. With this design, the three-fingered hand has a compact size and a lightweight with a mass of 150.25 grams imitating the human being hand in terms of size and weight. The hand also successfully grasped objects with different shapes and weights up to 500 g. Even though the number of PAM actuators equals the number of Degrees of Freedom (DOF), the design guarantees driving of three joints by only one actuator reducing the number of required actuators from 3 to 1. Therefore, this hand is suitable for researches of robotic applications in terms of design, cost and ability to be equipped with several types of sensors.

Successful conservative treatment outcomes and clinical characteristics of congenital hypoplasia of the extensor tendon central slip.

PubMed

Hidaka, N; Uemura, T; Nakamura, H

2017-03-01

Congenital hypoplasia of the extensor tendon central slip is a rare entity. This article describes the clinical characteristics in a series of 22 fingers in 16 patients (mean age: 10 months), and the outcomes of conservative treatment. Nine of 22 fingers were classified as slender or hypoplastic. Treatment with bracing was successful in 21 digits, resulting in full active extension of the proximal interphalangeal joint at a mean of 8.5 months after treatment. Bracing was unsuccessful in one digit, in which operative treatment resulted in a successful outcome. Some residual deformity was observed in ten fingers after a mean follow-up period of 2 years and 1 month. Congenital hypoplasia of the central slip can be treated successfully by the conservative hand bracing when worn with full compliance. Treatment time is extended by the infrequent application of the hand brace or in the case of hypoplastic slender fingers. IV.

Motor impairments related to brain injury timing in early hemiparesis. Part II: abnormal upper extremity joint torque synergies.

PubMed

Sukal-Moulton, Theresa; Krosschell, Kristin J; Gaebler-Spira, Deborah J; Dewald, Julius P A

2014-01-01

Extensive neuromotor development occurs early in human life, and the timing of brain injury may affect the resulting motor impairment. In Part I of this series, it was demonstrated that the distribution of weakness in the upper extremity depended on the timing of brain injury in individuals with childhood-onset hemiparesis. The goal of this study was to characterize how timing of brain injury affects joint torque synergies, or losses of independent joint control. Twenty-four individuals with hemiparesis were divided into 3 groups based on the timing of their injury: before birth (PRE-natal, n = 8), around the time of birth (PERI-natal, n = 8), and after 6 months of age (POST-natal, n = 8). Individuals with hemiparesis and 8 typically developing peers participated in maximal isometric shoulder, elbow, wrist, and finger torque generation tasks while their efforts were recorded by a multiple degree-of-freedom load cell. Motor output in 4 joints of the upper extremity was concurrently measured during 8 primary torque generation tasks to quantify joint torque synergies. There were a number of significant coupling patterns identified in individuals with hemiparesis that differed from the typically developing group. POST-natal differences were most noted in the coupling of shoulder abductors with elbow, wrist, and finger flexors, while the PRE-natal group demonstrated significant distal joint coupling with elbow flexion. The torque synergies measured provide indirect evidence for the use of bulbospinal pathways in the POST-natal group, while those with earlier injury may use relatively preserved ipsilateral corticospinal motor pathways.

Quantitative three-dimensional photoacoustic tomography of the finger joints: an in vivo study

NASA Astrophysics Data System (ADS)

Sun, Yao; Sobel, Eric; Jiang, Huabei

2009-11-01

We present for the first time in vivo full three-dimensional (3-D) photoacoustic tomography (PAT) of the distal interphalangeal joint in a human subject. Both absorbed energy density and absorption coefficient images of the joint are quantitatively obtained using our finite-element-based photoacoustic image reconstruction algorithm coupled with the photon diffusion equation. The results show that major anatomical features in the joint along with the side arteries can be imaged with a 1-MHz transducer in a spherical scanning geometry. In addition, the cartilages associated with the joint can be quantitatively differentiated from the phalanx. This in vivo study suggests that the 3-D PAT method described has the potential to be used for early diagnosis of joint diseases such as osteoarthritis and rheumatoid arthritis.

Reorganization of finger coordination patterns through motor exploration in individuals after stroke.

PubMed

Ranganathan, Rajiv

2017-09-11

Impairment of hand and finger function after stroke is common and affects the ability to perform activities of daily living. Even though many of these coordination deficits such as finger individuation have been well characterized, it is critical to understand how stroke survivors learn to explore and reorganize their finger coordination patterns for optimizing rehabilitation. In this study, I examine the use of a body-machine interface to assess how participants explore their movement repertoire, and how this changes with continued practice. Ten participants with chronic stroke wore a data glove and the finger joint angles were mapped on to the position of a cursor on a screen. The task of the participants was to move the cursor back and forth between two specified targets on a screen. Critically, the map between the finger movements and cursor motion was altered so that participants sometimes had to generate coordination patterns that required finger individuation. There were two phases to the experiment - an initial assessment phase on day 1, followed by a learning phase (days 2-5) where participants trained to reorganize their coordination patterns. Participants showed difficulty in performing tasks which had maps that required finger individuation, and the degree to which they explored their movement repertoire was directly related to clinical tests of hand function. However, over four sessions of practice, participants were able to learn to reorganize their finger movement coordination pattern and improve their performance. Moreover, training also resulted in improvements in movement repertoire outside of the context of the specific task during free exploration. Stroke survivors show deficits in movement repertoire in their paretic hand, but facilitating movement exploration during training can increase the movement repertoire. This suggests that exploration may be an important element of rehabilitation to regain optimal function.

Analysis of Hand and Wrist Postural Synergies in Tolerance Grasping of Various Objects

PubMed Central

Liu, Yuan; Jiang, Li; Yang, Dapeng; Liu, Hong

2016-01-01

Human can successfully grasp various objects in different acceptable relative positions between human hand and objects. This grasp functionality can be described as the grasp tolerance of human hand, which is a significant functionality of human grasp. To understand the motor control of human hand completely, an analysis of hand and wrist postural synergies in tolerance grasping of various objects is needed. Ten healthy right-handed subjects were asked to perform the tolerance grasping with right hand using 6 objects of different shapes, sizes and relative positions between human hand and objects. Subjects were wearing CyberGlove attaching motion tracker on right hand, allowing a measurement of the hand and wrist postures. Correlation analysis of joints and inter-joint/inter-finger modules were carried on to explore the coordination between joints or modules. As the correlation between hand and wrist module is not obvious in tolerance grasping, individual analysis of wrist synergies would be more practical. In this case, postural synergies of hand and wrist were then presented separately through principal component analysis (PCA), expressed through the principal component (PC) information transmitted ratio, PC elements distribution and reconstructed angle error of joints. Results on correlation comparison of different module movements can be well explained by the influence factors of the joint movement correlation. Moreover, correlation analysis of joints and modules showed the wrist module had the lowest correlation among all inter-finger and inter-joint modules. Hand and wrist postures were both sufficient to be described by a few principal components. In terms of the PC elements distribution of hand postures, compared with previous investigations, there was a greater proportion of movement in the thumb joints especially the interphalangeal (IP) and opposition rotation (ROT) joint. The research could serve to a complete understanding of hand grasp, and the design, control of the anthropomorphic hand and wrist. PMID:27580298

Development of photoacoustic imaging system of finger vasculature using ring-shaped ultrasound transducer

NASA Astrophysics Data System (ADS)

Nishiyama, Misaki; Namita, Takeshi; Kondo, Kengo; Yamakawa, Makoto; Shiina, Tsuyoshi

2018-02-01

For early diagnosis of rheumatoid arthritis (RA), it is important to visualize its potential marker, vascularization in the synovial membrane of the finger joints. Photoacoustic (PA) imaging, which can image blood vessels at high contrast and resolution is expected to be a potential modality for earlier diagnosis of RA. In previous studies of PA finger imaging, different acoustic schemes such as linear or arc-shaped arrays have been utilized, but these have limited detection views, rendering inaccurate reconstruction, and most of them require rotational detection. We are developing a photoacoustic system for finger vascular imaging using a ring-shaped array ultrasound transducer. By designing the ring-array based on simulations and phantom experiments, we have created a system that can image multiple objects of different diameters and has the potential to image small objects 0.1-0.5mm in diameter at accurate positions by providing PA and ultrasound echo images simultaneously. In addition, we determined that full width at half maximum (FWHM) of the slice direction corresponded to that of the simulation. In the future, this system may visualize the 3-D vascularization of RA patients' fingers.

Case Report: The casting motion to mobilize stiffness technique for rehabilitation after a crush and degloving injury of the hand.

PubMed

Midgley, Robyn

2016-01-01

Case report. This case report describes the use of the casting motion to mobilize stiffness (CMMS) technique in the management of a crush and degloving injury of the hand. The patient was unable to attend multiple hand therapy sessions due to geographic constraints. The CMMS technique involved the application of a nonremovable plaster of paris cast that selectively immobilizes proximal joints in an ideal position while constraining distal joints to direct desired motion over a long period. This uses active motion only. Traditional hand therapy techniques or modalities are not used. This treatment approach was beneficial to the patient as a minimum of 2 appointments per month were needed to regain functional hand use. To document the use of the CMMS technique as an effective treatment approach in the management of a crush and degloving injury of the hand. The CMMS technique was applied to the patient's left (nondominant) hand 8 weeks after injury. The technique's aim was to improve the 30° flexion deformity of the left wrist and flexion contractures of the index, middle, and ring fingers with a total active motion of 0°. Orthotic devices and traditional therapy were applied once joint stiffness was resolved, and a normal pattern of motion was reinstated. At 6 months, substantial improvement was noted in wrist as well as metacarpophalangeal and interphalangeal joints. Total active motion exceeded 170° in all fingers excellent functional outcome resulted as measured with the upper limb functional index short form-10. The upper limb functional index increased from 0% to 55% of preinjury status (or capacity) over the 18 months of therapy. Brief immobilization through casting causes certain functional losses, but these are temporary and reversible. Finger stiffness, edema, and tissue fibrosis were successfully managed with the CMMS technique without the need for attendance at multiple hand therapy sessions. Level V. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Vibration-Resistant Support for Halide Lamps

NASA Technical Reports Server (NTRS)

Kiss, J.

1987-01-01

Lamp envelope protected against breakage. Old and new mounts for halide arc lamp sealed in housing with parabolic refector and quartz window. New version supports lamp with compliant garters instead of rigid brazed joint at top and dimensionally unstable finger stock at bottom.

Functional range of movement of the hand: declination angles to reachable space.

PubMed

Pham, Hai Trieu; Pathirana, Pubudu N; Caelli, Terry

2014-01-01

The measurement of the range of hand joint movement is an essential part of clinical practice and rehabilitation. Current methods use three finger joint declination angles of the metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints. In this paper we propose an alternate form of measurement for the finger movement. Using the notion of reachable space instead of declination angles has significant advantages. Firstly, it provides a visual and quantifiable method that therapists, insurance companies and patients can easily use to understand the functional capabilities of the hand. Secondly, it eliminates the redundant declination angle constraints. Finally, reachable space, defined by a set of reachable fingertip positions, can be measured and constructed by using a modern camera such as Creative Senz3D or built-in hand gesture sensors such as the Leap Motion Controller. Use of cameras or optical-type sensors for this purpose have considerable benefits such as eliminating and minimal involvement of therapist errors, non-contact measurement in addition to valuable time saving for the clinician. A comparison between using declination angles and reachable space were made based on Hume's experiment on functional range of movement to prove the efficiency of this new approach.

Splint therapy for trigger finger in children.

PubMed

Tsuyuguchi, Y; Tada, K; Kawaii, H

1983-02-01

During the last 9 years, 83 trigger digits in 65 children were treated using a modified coil spring splint which maintains the interphalangeal (IP) joint in neutral extension or hyperextension. Sixty-two digits (75%) were completely healed following splint therapy alone, after an average period of splinting for 9.4 months. Eight digits which did not improve with splinting were surgically treated. Splint therapy to maintain the IP joint in neutral extension or hyperextension proved markedly effective in our series.

Intramedullary Percutaneous Fixation of Extra-Articular Proximal and Middle Phalanx Fractures.

PubMed

Jovanovic, Nebojsa; Aldlyami, Ehab; Saraj, Basem; Fm Seidam, Mohamed; Badawi, Hamed; Shaat, Ahmed; Alawadi, Khalid; Dodakundi, Chaitanya

2018-06-01

Multiple methods have been described for treating unstable proximal and middle phalangeal fractures. Irrespective of using an open or closed technique of fixation, stiffness and extensor lag at the proximal/distal interphalangeal joint almost always occur. This issue can be avoided by allowing the patients to mobilize the fingers out of plaster or splint as early as possible from the day of surgery. We describe a technique of intramedullary percutaneous fixation of extra-articular proximal and middle phalanx fractures allowing immediate mobilization of fingers, concurrent stabilization with progressive healing and thus preventing such complications.

[Pulley for strengthening a muscle replacement operation across two joints in brachial plexus lesion: description of the surgical technique].

PubMed

Berger, A; Schaller, E; Becker, M H

1994-01-01

The reconstruction of lost muscle functions in cases of brachial plexus lesion is possible even in those cases where primary nerve reconstruction was not performed or unsuccessful. If there are only few motor nerves available, we prefer free latissimus dorsi transplantation or pedicled latissimus dorsi transposition for replacement of biceps and finger flexors. The combination of elbow flexion and finger flexion becomes possible when the transposed motor is passed around a suitable pulley in the elbow region like the flexor carpi ulnaris or carpi radialis.

Knuckle Pads—A common problem but good to treat by Laser

NASA Astrophysics Data System (ADS)

Herold, Manfred; Russe-Wilflingseder, Katharina

2010-05-01

Knuckle pads are common skin lesions not disease associated and seen as thickended skin like nodules situated usually on the dorsal site of the proximal interphalangeal joints. Neither medical nor surgical procedures are very effective to remove knuckle pads. A women 22 years of age with knuckle pads on the fingers two and three on both hands which reoccurred after surgical resections was successful treated with a long pulsed Erbium:YAG laser. All four fingers were ablated within one single treatment. The aesthetic result was excellent and lasted at least for 18 months.

Exploring social influences on the joint Simon task: empathy and friendship

PubMed Central

Ford, Ruth M.; Aberdein, Bradley

2015-01-01

Tasks for which people must act together to achieve a goal are a feature of daily life. The present study explored social influences on joint action using a Simon procedure for which participants (n = 44) were confronted with a series of images of hands and asked to respond via button press whenever the index finger wore a ring of a certain color (red or green) regardless of pointing direction (left or right). In an initial joint condition they performed the task while sitting next to another person (friend or stranger) who responded to the other color. In a subsequent individual condition they repeated the task on their own; additionally, they completed self-report tests of empathy. Consistent with past research, participants reacted more quickly when the finger pointed toward them rather than their co-actor (the Simon Effect or SE). The effect remained robust when the co-actor was no longer present and was unaffected by degree of acquaintance; however, its magnitude was correlated positively with empathy only among friends. For friends, the SE was predicted by cognitive perspective taking when the co-actor was present and by propensity for fantasizing when the co-actor was absent. We discuss these findings in relation to social accounts (e.g., task co-representation) and non-social accounts (e.g., referential coding) of joint action. PMID:26217281

Open extensor tendon injuries: an epidemiologic study.

PubMed

Patillo, Dominic; Rayan, Ghazi M

2012-01-01

To report the epidemiology, mechanism, anatomical location, distribution, and severity of open extensor tendon injuries in the digits, hand, and forearm as well as the frequency of associated injuries to surrounding bone and soft tissue. Retrospective chart review was conducted for patients who had operative repair of open digital extensor tendon injuries in all zones within an 11-year period. Data was grouped according to patient characteristics, zone of injury, mechanism of injury, and presence of associated injury. Statistical analysis was used to determine the presence of relevant associations. Eighty-six patients with 125 severed tendons and 105 injured digits were available for chart reviews. Patients were predominantly males (83%) with a mean age of 34.2 years and the dominant extremity was most often injured (60%). The thumb was the most commonly injured (25.7%), followed by middle finger (24.8), whereas small finger was least affected (10.5%). Sharp laceration was the most common mechanism of injury (60%), and most of these occurred at or proximal to the metacarpophalangeal joints. Most saw injuries occurred distal to the metacarpophalangeal joint. Zone V was the most commonly affected in the fingers (27%) while zone VT was the most commonly affected in the thumb (69%). Associated injuries to bone and soft tissue occurred in 46.7% of all injuries with saw and crush/avulsions being predictive of fractures and damage to the underlying joint capsule. The extensor mechanism is anatomically complex, and open injuries to the dorsum of the hand, wrist, and forearm, especially of crushing nature and those inflicted by saws, must be thoroughly evaluated. Associated injuries should be ruled out in order to customize surgical treatment and optimize outcome.

Talbot phase-contrast X-ray imaging for the small joints of the hand

PubMed Central

Stutman, Dan; Beck, Thomas J; Carrino, John A; Bingham, Clifton O

2011-01-01

A high resolution radiographic method for soft tissues in the small joints of the hand would aid in the study and treatment of Rheumatoid Arthritis (RA) and Osteoarthritis (OA), which often attacks these joints. Of particular interest would be imaging with <100 μm resolution the joint cartilage, whose integrity is a main indicator of disease. Differential phase-contrast or refraction based X-ray imaging (DPC) with Talbot grating interferometers could provide such a method, since it enhances soft tissue contrast and it can be implemented with conventional X-ray tubes. A numerical joint phantom was first developed to assess the angular sensitivity and spectrum needed for a hand DPC system. The model predicts that due to quite similar refraction indexes for joint soft tissues, the refraction effects are very small, requiring high angular resolution. To compare our model to experiment we built a high resolution bench-top interferometer using 10 μm period gratings, a W anode tube and a CCD based detector. Imaging experiments on animal cartilage and on a human finger support the model predictions. For instance, the estimated difference between the index of refraction of cartilage and water is of only several percent at ~25 keV mean energy, comparable to that between the linear attenuation coefficients. The potential advantage of DPC imaging comes thus mainly from the edge enhancement at the soft tissue interfaces. Experiments using a cadaveric human finger are also qualitatively consistent with the joint model, showing that refraction contrast is dominated by tendon embedded in muscle, with the cartilage layer difficult to observe in our conditions. Nevertheless, the model predicts that a DPC radiographic system for the small hand joints of the hand could be feasible using a low energy quasi-monochromatic source, such as a K-edge filtered Rh or Mo tube, in conjunction with a ~2 m long ‘symmetric’ interferometer operated in a high Talbot order. PMID:21841214

Talbot phase-contrast x-ray imaging for the small joints of the hand

NASA Astrophysics Data System (ADS)

Stutman, Dan; Beck, Thomas J.; Carrino, John A.; Bingham, Clifton O.

2011-09-01

A high-resolution radiographic method for soft tissues in the small joints of the hand would aid in the study and treatment of rheumatoid arthritis (RA) and osteoarthritis (OA), which often attacks these joints. Of particular interest would be imaging with <100 µm resolution the joint cartilage, whose integrity is a main indicator of disease. Differential phase-contrast (DPC) or refraction-based x-ray imaging with Talbot grating interferometers could provide such a method, since it enhances soft tissue contrast and can be implemented with conventional x-ray tubes. A numerical joint phantom was first developed to assess the angular sensitivity and spectrum needed for a hand DPC system. The model predicts that, due to quite similar refraction indexes for joint soft tissues, the refraction effects are very small, requiring high angular resolution. To compare our model to experiment we built a high-resolution bench-top interferometer using 10 µm period gratings, a W anode tube and a CCD-based detector. Imaging experiments on animal cartilage and on a human finger support the model predictions. For instance, the estimated difference between the index of refraction of cartilage and water is of only several percent at ~25 keV mean energy, comparable to that between the linear attenuation coefficients. The potential advantage of DPC imaging thus comes mainly from the edge enhancement at the soft tissue interfaces. Experiments using a cadaveric human finger are also qualitatively consistent with the joint model, showing that refraction contrast is dominated by tendon embedded in muscle, with the cartilage layer difficult to observe in our conditions. Nevertheless, the model predicts that a DPC radiographic system for the small hand joints of the hand could be feasible using a low energy quasi-monochromatic source, such as a K-edge filtered Rh or Mo tube, in conjunction with a ~2 m long 'symmetric' interferometer operated in a high Talbot order.

Horizontal slip along Alleghanian joints of the Appalachian plateau: evidence showing that mild penetrative strain does little to change the pristine appearance of early joints

NASA Astrophysics Data System (ADS)

Engelder, Terry; Haith, Benjamin F.; Younes, Amgad

2001-07-01

Some Alleghanian joints in black shales of the Geneseo and Middlesex Formations of the Catskill Delta complex, Finger Lakes district, New York, slipped horizontally up to 8 cm. Horizontal slip is measured by the offset of ENE-striking joints. Alleghanian joints striking 330-350° display a right-lateral slip with an average value of 1.9 cm, while joints striking 004-010° slip in the left-lateral sense with an average value of 1.3 cm. The maximum horizontal stress (SH) driving this slip falls between 350° and 004°, the orientation of local Alleghanian layer-parallel shortening as indicated by both disjunctive and pencil cleavage. By commonality of orientation, we infer that slip on Alleghanian joints is driven contemporaneously with layer-parallel shortening. If so, the offset ENE-striking joints predate the Alleghanian stress field. These observations mean that both pre-Alleghanian and early Alleghanian joints persist through a period of penetrative strain.

Surface properties of thermally treated composite wood panels

NASA Astrophysics Data System (ADS)

Croitoru, Catalin; Spirchez, Cosmin; Lunguleasa, Aurel; Cristea, Daniel; Roata, Ionut Claudiu; Pop, Mihai Alin; Bedo, Tibor; Stanciu, Elena Manuela; Pascu, Alexandru

2018-04-01

Composite finger-jointed spruce and oak wood panels have been thermally treated under standard pressure and oxygen content conditions at two different temperatures, 180 °C and respectively 200 °C for short time periods (3 and 5 h). Due to the thermally-aided chemical restructuration of the wood components, a decrease in water uptake and volumetric swelling values with up to 45% for spruce and 35% for oak have been registered, comparing to the reference samples. In relation to water resistance, a 15% increase of the dispersive component of the surface energy has been registered for the thermal-treated spruce panels, which impedes water spreading on the surface. The thermal-treated wood presents superior resistance to accelerated UV exposure and subsequently, with up to 10% higher Brinell hardness values than reference wood. The proposed thermal treatment improves the durability of the finger-jointed wood through a more economically and environmental friendly method than traditional impregnation, with minimal degradative impact on the structural components of wood.

[Second toe transfer in congenital hand differences].

PubMed

Dautel, G; Barbary, S

2008-12-01

In congenital hand differences, microsurgical toe transfer involves the creation of one or several rays in a child that never possessed them before. Second toe transplantation was uniformly used in this series that include 65 consecutive cases. Etiologies were represented by symbrachydactyly, constriction band syndrome or central cleft hand. Second toe transfer was performed with or without the MTP joint and followed by proximal ray resection of the donor toe. In the vast majority of theses cases, transplantation was performed in adactylic or monodactylic hand, the ultimate functional goal was the creation of a "tip-to-tip" two fingers pinch. Implantation site was chosen according to the situation of the existing finger(s). The existence of a functioning recipient MCP joint was one of the key factors of the final functional outcome. There were two vascular failures in this series with complete necrosis of the transplanted toe. Two additional toes appeared mediocre with respect to the overall transfer integration. The final mobility of the fingers reconstructed was measured using the total active motion score. Average TAM was poor (42 degrees +/-24 degrees ). In 12 out of 15 patients that were evaluated with a follow-up of at least five years, the static two-point discrimination was found to be excellent (less than 6mm). Our series did not allow us to establish a firm correlation between the type of nerve suture used and the quality of sensory recovery. Growth was measured as a percentage of the intact second toe (68 to 95%). All children on a long term basis had a normal gait without any impediment during sports or leisure activities. Clinical results obtained in this series lead to think that the cerebral cortex has got some plasticity which allows the integration of the transplants.

A Compliant Four-bar Linkage Mechanism that Makes the Fingers of a Prosthetic Hand More Impact Resistant

PubMed Central

Choi, Kyung Yun; Akhtar, Aadeel; Bretl, Timothy

2017-01-01

Repeated mechanical failure due to accidental impact is one of the main reasons why people with upper-limb amputations abandon commercially-available prosthetic hands. To address this problem, we present the design and evaluation of a compliant four-bar linkage mechanism that makes the fingers of a prosthetic hand more impact resistant. Our design replaces both the rigid input and coupler links with a monolithic compliant bone, and replaces the follower link with three layers of pre-stressed spring steel. This design behaves like a conventional four-bar linkage but adds lateral compliance and eliminates a pin joint, which is a main site of failure on impact. Results from free-end and fixed-end impact tests show that, compared to those made with a conventional four-bar linkage, fingers made with our design absorb up to 11% more energy on impact with no mechanical failure. We also show the integration of these fingers in a prosthetic hand that is low-cost, light-weight, and easy to assemble, and that has grasping performance comparable to commercially-available hands. PMID:29527386

A practical guide for performing arthrography under fluoroscopic or ultrasound guidance.

PubMed

Lungu, Eugen; Moser, Thomas P

2015-12-01

We propose a practical approach for performing arthrography with fluoroscopic or ultrasound guidance. Different approaches to the principal joints of the upper limb (shoulder, elbow, wrist and fingers), lower limb (hip, knee, ankle and foot) as well as the facet joints of the spine are discussed and illustrated with numerous drawings. Whenever possible, we emphasise the concept of targeting articular recesses, which offers many advantages over traditional techniques aiming at the joint space. • Arthrography remains a foremost technique in musculoskeletal radiology • Most joints can be successfully accessed by targeting the articular recess • Targeting the recess offers several advantages over traditional approaches • Ultrasound-guidance is now favoured over fluoroscopy and targeting the recess is equally applicable.

Detection of rheumatoid arthritis by evaluation of normalized variances of fluorescence time correlation functions

NASA Astrophysics Data System (ADS)

Dziekan, Thomas; Weissbach, Carmen; Voigt, Jan; Ebert, Bernd; MacDonald, Rainer; Bahner, Malte L.; Mahler, Marianne; Schirner, Michael; Berliner, Michael; Berliner, Birgitt; Osel, Jens; Osel, Ilka

2011-07-01

Fluorescence imaging using the dye indocyanine green as a contrast agent was investigated in a prospective clinical study for the detection of rheumatoid arthritis. Normalized variances of correlated time series of fluorescence intensities describing the bolus kinetics of the contrast agent in certain regions of interest were analyzed to differentiate healthy from inflamed finger joints. These values are determined using a robust, parameter-free algorithm. We found that the normalized variance of correlation functions improves the differentiation between healthy joints of volunteers and joints with rheumatoid arthritis of patients by about 10% compared to, e.g., ratios of areas under the curves of raw data.

[10 congenital trigger fingers. Apropos of a case report].

PubMed

Moutet, F; Lebrun, C; Sartorius, C

1987-01-01

Ten congenital triggers fingers have been treated on a 3 years old girl after correction of congenital bilateral club feet. Such a case, without any other congenital malformation seems to be unique in the French literature and only found twice in the English one. This child in spite of a normal growth and good psychomotor development, presents an unusual face, with a mouth a little bit too small, but her karyotype is normal. No trismus and no microstomia were found to enable this case to be classified in a specific syndrome. The right diagnosis may be a non evolutive arthrogryposis of the extremities. Dividing the ten proximal pulleys (A1) let 10 voluminous nodules pass through and allowed full range of motion in nine out of ten fingers. A remaining flexion deformity of the proximal interphalangeal joint needed an anterior arthrolysis, the final result was good.

A New Clinical Sign of Lumbrical Plus Finger.

PubMed

Schuind, Frédéric A; Moungondo, Fabian; Van Wetter, Pierre

2018-06-01

Paradoxical finger extension is the classical clinical presentation of the lumbrical plus syndrome. We report a new additional sign, increased metacarpophalangeal flexion of the involved finger when the patient tries to make a fist. Three cases of lumbrical tightness are discussed, illustrating this new sign in 3 different clinical settings. The new sign was present in all 3 cases. Lumbrical tenotomy corrected the paradoxical interphalangeal extension and partly the increased metacarpophalangeal flexion. The lumbrical tendon has a relatively high moment arm relative to the metacarpophalangeal joint, which could explain the basis of this clinical sign. This new physical examination sign may help in diagnosing the lumbrical plus syndrome, a subtle complication of flexor digitorum profundus lesions that is not easily diagnosed but which is easily addressed. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Clinical Assessment and Diagnostics of Patients With Hand Disorders: A Case Study Approach.

PubMed

Leow, Mabel Qi He; Lim, Rebecca Qian Ru; Tay, Shian Chao

Clinical assessment of the hand is important for diagnosing underlying hand disorders. Using a case study approach, the clinical assessment for three disorders of the hands is presented: trigger finger (stenosing tenosynovitis), carpal tunnel syndrome, and ulnar-sided wrist injury (styloid impingement). We assess the annular one pulley and finger range of motion for patients with trigger finger. To diagnose for carpal tunnel syndrome, assessment for Tinel's sign, Phalen's sign, abductor pollicis brevis muscle bulk, two-point discrimination, and obtaining a nerve conduction study are performed. Assessment for ulnar-sided wrist injury includes wrist range of motion, assessment of distal radial ulnar joint stability, provocation tests, grip strength, x-ray, and magnetic resonance imaging. This article begins with a description of the hand and wrist anatomy. For each case study, the clinical history is described, followed by a discussion of the pathophysiology, clinical assessments, and diagnostic tests.

CNT coated thread micro-electro-mechanical system for finger proprioception sensing

NASA Astrophysics Data System (ADS)

Shafi, A. A.; Wicaksono, D. H. B.

2017-04-01

In this paper, we aim to fabricate cotton thread based sensor for proprioceptive application. Cotton threads are utilized as the structural component of flexible sensors. The thread is coated with multi-walled carbon nanotube (MWCNT) dispersion by using facile conventional dipping-drying method. The electrical characterization of the coated thread found that the resistance per meter of the coated thread decreased with increasing the number of dipping. The CNT coated thread sensor works based on piezoresistive theory in which the resistance of the coated thread changes when force is applied. This thread sensor is sewed on glove at the index finger between middle and proximal phalanx parts and the resistance change is measured upon grasping mechanism. The thread based microelectromechanical system (MEMS) enables the flexible sensor to easily fit perfectly on the finger joint and gives reliable response as proprioceptive sensing.

Freely Chosen Index Finger Tapping Frequency Is Increased in Repeated Bouts of Tapping.

PubMed

Hansen, Ernst Albin; Ebbesen, Brian Duborg; Dalsgaard, Ane; Mora-Jensen, Mark Holten; Rasmussen, Jakob

2015-01-01

Healthy individuals (n = 40) performed index finger tapping at freely chosen frequency during repeated bouts and before and after near-maximal muscle action consisting of 3 intense flexions of the index finger metacarpal phalangeal joint. One experiment showed, unexpectedly, that a bout of tapping increased the tapping frequency in the subsequent bout. Thus, a cumulating increase of 8.2 ± 5.4% (p < .001) occurred across 4 bouts, which were all separated by 10 min rest periods. Follow-up experiments revealed that tapping frequency was still increased in consecutive bouts when rest periods were extended to 20 min. Besides, near-maximal muscle activation, followed by 5 min rest, did not affect the tapping frequency. In conclusion, freely chosen tapping frequency was increased in repeated bouts of tapping, which were separated by 10-20 min rest periods. The observed phenomenon is suggested to be termed repeated bout rate enhancement.

Two case reports-Use of relative motion orthoses to manage extensor tendon zones III and IV and sagittal band injuries in adjacent fingers.

PubMed

Hirth, Melissa J; Howell, Julianne W; O'Brien, Lisa

Case report. Injuries to adjacent fingers with differing extensor tendon (ET) zones and/or sagittal band pose a challenge to therapists as no treatment guidelines exist. This report highlights how the relative motion flexion/extension (RMF/RME) concepts were combined into one orthosis to manage a zone IV ET repair (RME) and a zone III central slip repair (RMF) in adjacent fingers (Case 1); and how a single RME orthosis was adapted to limit proximal interphalangeal joint motion to manage multi-level ET zone III-IV injuries and a sagittal band repair in adjacent fingers (case 2). Adapted relative motion orthoses allowed early active motion and graded exercises based on clinical reasoning and evidence. Outcomes were standard TAM% and Miller's criteria. 'Excellent' and 'good' outcomes were achieved by twelve weeks post surgery. Both cases returned to unrestricted work at 6 and 7 weeks. Neither reported functional deficits at discharge. Outcomes in 2 cases involving multiple digit injuries exceeded those previously reported for ET zone III-IV repairs. Relative motion orthoses can be adapted and applied to multi-finger injuries, eliminating the need for multiple, bulky or functionally-limiting orthoses. 4. Copyright © 2017 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

A feasibility study of hand kinematics for EVA analysis using magnetic resonance imaging

NASA Technical Reports Server (NTRS)

Dickenson, Reuben D.; Lorenz, Christine H.; Peterson, Steven W.; Strauss, Alvin M.; Main, John A.

1992-01-01

A new method for analyzing the kinematics of joint motion using magnetic resonance imaging (MRI) is described. The reconstruction of the metacarpalphalangeal joint of the left index finger into a 3D graphic display is shown. From the reconstructed volumetric images, measurements of the angles of movement of the applicable bones are obtained and processed by analyzing the screw motion of the joint. Landmark positions are chosen at distinctive locations of the joint at fixed image threshold intensity levels to ensure repeatability. The primarily 2D planar motion of this joint is then studied using a method of constructing coordinate systems using three or more points. A transformation matrix based on a world coordinate system describes the location and orientation of the local target coordinate system. The findings show the applicability of MRI to joint kinematics for gaining further knowledge of the hand-glove design for EVA.

Circuit For Control Of Electromechanical Prosthetic Hand

NASA Technical Reports Server (NTRS)

Bozeman, Richard J., Jr.

1995-01-01

Proposed circuit for control of electromechanical prosthetic hand derives electrical control signals from shoulder movements. Updated, electronic version of prosthesis, that includes two hooklike fingers actuated via cables from shoulder harness. Circuit built around favored shoulder harness, provides more dexterous movement, without incurring complexity of computer-controlled "bionic" or hydraulically actuated devices. Additional harness and potentiometer connected to similar control circuit mounted on other shoulder. Used to control stepping motor rotating hand about prosthetic wrist to one of number of angles consistent with number of digital outputs. Finger-control signals developed by circuit connected to first shoulder harness transmitted to prosthetic hand via sliprings at prosthetic wrist joint.

System description document for the Anthrobot-2: A dexterous robot hand

NASA Technical Reports Server (NTRS)

Ali, Michael S.; Engler, Charles, Jr.

1991-01-01

The Anthrobot-2 is an anatomically correct, fully functioning robot hand. The number of fingers, the proportions of the links, the placement and motion of the thumb, and the shape of the palm follow those of the human hand. Each of the finger and thumb joints are servo-controlled. The Anthrobot-2 also includes a two-degree-of-freedom wrist. The entire package, including wrist, hand, and actuators, will mount on the ends of a variety of industrial manipulators. A patent has been applied for on the design. The Anthrobot-2 will be useful in tasks where dexterous manipulation or telemanipulation are required.

Pollicisation: The Myth about Creating a Pseudo-Trapezium.

PubMed

Mennen, Ulrich

2018-06-01

We have performed 14 pollicisations without creating a "pseudo-trapezium" from the metacarpal head. The entire metacarpal of the intended finger to be pollicised is removed and the proximal phalanx of the finger is inserted into the space left by the base of the excised metacarpal. The results are good to excellent in all 14 cases followed for 2-9 years. The advantages are that the operation is much simpler, thus also much quicker. The new thumb looks more like a thumb (not too long) and is more stable (ball-and-socket joint), with no long term complications often seen with the pseudo-trapezium.

Kirschner-wire fixation for postburn flexion contracture deformity and consequences on articular surface.

PubMed

Sungur, Nezih; Ulusoy, Mustafa Gürhan; Boyacgil, Süreyya; Ortaparmak, Hülya; Akyüz, Mihriban; Ortak, Turgut; Koçer, Uğur; Sensöz, Omer

2006-02-01

Kirschner-wire (K-wire) fixation for 3-6 weeks is an approved method for stabilization of the fingers after the release of flexion contracture deformity. On the other hand, articular surface damage in small joints due to pin fixation is still a topic of debate. Reports claiming permanent joint destruction due to this procedure exist in the literature. To clarify this doubt, a prospective study was carried out in 72 patients with flexion contracture of the hand fingers. After the surgical release of the deformity, immobilization of the interphalangeal (IP) and metacarpophalangeal (MCP) joints was carried out with K-wire fixation for 3 weeks. Clinical evaluation of the patients was accomplished with total active motion (TAM), grip, and pinch force measurements, whereas magnetic resonance (MR) and radionuclide imaging were used as radiodiagnostic tools. Mean follow-up period of the patients was 32 months. Satisfactory results were obtained in terms of functional and esthetic aspects. Evaluation of the data derived from the clinical and radiologic measurements revealed no permanent articular surface damage. K-wire fixation was documented to be an invaluable therapeutic approach not only to prevent recurrence of the contracture deformity but also to stabilize the skin graft effectively. This technique was concluded to provide effective immobilization without permanent articular damage.

Analysis of the reliability and reproducibility of goniometry compared to hand photogrammetry

PubMed Central

de Carvalho, Rosana Martins Ferreira; Mazzer, Nilton; Barbieri, Claudio Henrique

2012-01-01

Objective: To evaluate the intra- and inter-examiner reliability and reproducibility of goniometry in relation to photogrammetry of hand, comparing the angles of thumb abduction, PIP joint flexion of the II finger and MCP joint flexion of the V finger. Methods: The study included 30 volunteers, who were divided into three groups: one group of 10 physiotherapy students, one group of 10 physiotherapists, and a third group of 10 therapists of the hand. Each examiner performed the measurements on the same hand mold, using the goniometer followed by two photogrammetry software programs; CorelDraw® and ALCimagem®. Results: The results revealed that the groups and the methods proposed presented inter-examiner reliability, generally rated as excellent (ICC 0.998 I.C. 95% 0.995 - 0.999). In the intra-examiner evaluation, an excellent level of reliability was found between the three groups. In the comparison between groups for each angle and each method, no significant differences were found between the groups for most of the measurements. Conclusion: Goniometry and photogrammetry are reliable and reproducible methods for evaluating measurements of the hand. However, due to the lack of similar references, detailed studies are needed to define the normal parameters between the methods in the joints of the hand. Level of Evidence II, Diagnostic Study. PMID:24453594

[Initial studies of the application of the linear signal transfer theory in evaluating diaphanoscopic examinations exemplified by rheumatism diagnosis].

PubMed

Beuthan, J; Cappius, H J; Hielscher, A; Hopf, M; Klose, A; Netz, U

2001-11-01

Rheumatoid arthritis affecting the small joints--in particular the fingers--has advantageous geometry for the transmission of near-infrared (NIR) light. Examination of the optical properties of tissues has revealed that as a result of changes to the capsule and synovial fluid there is a considerable increase in photon scattering already in the early stages of the disease--in particular around 685 nm. This suggests the appropriateness of analysing the photon density profile resulting from punctiform irradiation of the joint. In a first approximation, the point spread function of transmitted photon density is confirmed to be proportional to a Gauss distribution, as suggested by Arridge. In accordance with the linear signal transfer theory, therefore, it is possible to establish a virtual transfer system described by a first-order differential equation. (The tissue optical conditions mu a < mu's and mu a = constant (mu a = absorption coefficient) were assumed). The parameter mu's (= reduced scattering coefficient) was determined by linear approximation of the Gauss distribution to the calculated or measured point spread function. For selected patient data, the mu's was determined in healthy and diseased finger joints (e.g. 10.1 cm-1 and 26.8 cm-1, respectively), and the results were in good agreement with those obtained experimentally.

Joint positions matter for ultrasound examination of RA patients-increased power Doppler signal in neutral versus flat position of hands.

PubMed

Husic, Rusmir; Lackner, Angelika; Stradner, Martin H; Hermann, Josef; Dejaco, Christian

2017-08-01

Position of joints might influence the result of US examination in patients with RA. The purpose of this work was to compare grey-scale (GS) and power Doppler (PWD) findings obtained in neutral vs flat position of hands. A cross-sectional study of 42 RA patients with active disease. Two dimensional and 3D sonography of wrists and MCP joints were conducted in two different joint positions: neutral position, which is a slight flexion of the fingers with relaxed extensor muscles; and flat position, where all palm and volar sides of fingers touch the Table. Two dimensional GS synovitis (GSS) and PWD signals were scored semi-quantitatively (0-3). For 3D sonography, the percentage of PWD voxels within a region of interest was calculated. GSS was not quantified using 3D sonography. Compared with neutral position, 2D PWD signals disappeared in 28.3% of joints upon flattening. The median global 2D PWD score (sum of all PWD scores of an individual patient) decreased from 8 to 3 ( P < 0.001), and the global 3D PWD voxel score from 3.8 to 0.9 ( P < 0.001). The reduction of PWD scores was similar in all joints (2D: minus 50%, 3D: minus 66.4-80.1%). Inter- and intrareader agreement of PWD results was good (intraclass correlation coefficient: 0.75-0.82). In RA, a neutral position of the hands is linked to a higher sensitivity of 2D and 3D sonography in detecting PWD signals at wrists and MCP joints, compared with a flat position. Standardization of the scanning procedure is essential for obtaining comparable US results in RA patients in trials and clinical routines. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Does the type of somatosensory information from the contralateral finger touch affect grip force control while lifting an object?

PubMed

Chen, Bing; Aruin, Alexander S

2013-11-27

The magnitude of grip force used to lift and transport a hand-held object is decreased if a light finger touch from the contralateral arm is provided to the wrist of the target arm. We investigated whether the type of contralateral arm sensory input that became available with the finger touch to the target arm affects the way grip force is reduced. Nine healthy subjects performed the same task of lifting and transporting an instrumented object with no involvement of the contralateral arm and when an index finger touch of the contralateral arm was provided to the wrist, elbow, and shoulder. Touching the wrist and elbow involved movements of the contralateral arm; no movements were produced while touching the shoulder. Grip force was reduced by approximately the same amount in all conditions with the finger touch compared to the no touch condition. This suggests that information from the muscle and joint receptors of the contralateral arm is used in control of grip force when a finger touch is provided to the wrist and elbow, and cutaneous information is utilized when lifting an object while touching the shoulder. The results of the study provide additional evidence to support the use of a second arm in the performance of activities of daily living and stress the importance of future studies investigating contralateral arm sensory input in grip force control. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Why Does Joint Attention Look Atypical in Autism?

PubMed Central

Gernsbacher, Morton Ann; Stevenson, Jennifer L.; Khandakar, Suraiya; Goldsmith, H. Hill

2014-01-01

This essay answers the question of why autistic children are less likely to initiate joint attention (e.g., use their index finger to point to indicate interest in something) and why they are less likely to respond to bids for their joint attention (e.g., turn their heads to look at something to which another person points). It reviews empirical evidence that autistic toddlers, children, adolescents, and adults can attend covertly, even to social stimuli, such as the direction in which another person’s eyes are gazing. It also reviews empirical evidence that autistics of various ages understand the intentionality of other persons’ actions. The essay suggests that autistics’ atypical resistance to distraction, atypical skill at parallel perception, and atypical execution of volitional actions underlie their atypical manifestations of joint attention. PMID:25520747

A Neuromuscular Electrical Stimulation (NMES) and robot hybrid system for multi-joint coordinated upper limb rehabilitation after stroke.

PubMed

Rong, Wei; Li, Waiming; Pang, Mankit; Hu, Junyan; Wei, Xijun; Yang, Bibo; Wai, Honwah; Zheng, Xiaoxiang; Hu, Xiaoling

2017-04-26

It is a challenge to reduce the muscular discoordination in the paretic upper limb after stroke in the traditional rehabilitation programs. In this study, a neuromuscular electrical stimulation (NMES) and robot hybrid system was developed for multi-joint coordinated upper limb physical training. The system could assist the elbow, wrist and fingers to conduct arm reaching out, hand opening/grasping and arm withdrawing by tracking an indicative moving cursor on the screen of a computer, with the support from the joint motors and electrical stimulations on target muscles, under the voluntary intention control by electromyography (EMG). Subjects with chronic stroke (n = 11) were recruited for the investigation on the assistive capability of the NMES-robot and the evaluation of the rehabilitation effectiveness through a 20-session device assisted upper limb training. In the evaluation, the movement accuracy measured by the root mean squared error (RMSE) during the tracking was significantly improved with the support from both the robot and NMES, in comparison with those without the assistance from the system (P < 0.05). The intra-joint and inter-joint muscular co-contractions measured by EMG were significantly released when the NMES was applied to the agonist muscles in the different phases of the limb motion (P < 0.05). After the physical training, significant improvements (P < 0.05) were captured by the clinical scores, i.e., Modified Ashworth Score (MAS, the elbow and the wrist), Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT), and Wolf Motor Function Test (WMFT). The EMG-driven NMES-robotic system could improve the muscular coordination at the elbow, wrist and fingers. ClinicalTrials.gov. NCT02117089 ; date of registration: April 10, 2014.

Three-dimensional movement analysis of handwriting in subjects with mild hemiparesis.

PubMed

Harada, Takako; Okajima, Yasutomo; Takahashi, Hidetoshi

2010-08-01

To investigate the effects of hemiparesis on handwriting using a 3-dimensional movement analyzer. Comparative case study. Ambulatory care clinic. Right-handed patients (n=25; mean age +/- SD, 62.3+/-10y) with mild right hemiparesis secondary to subcortical stroke, and age-matched (n=10; 65.6+/-13y) and age-unmatched (n=15; 32.4+/-10y) control subjects. Not applicable. Time required to write a Japanese character of 2 different sizes and average speed of handwriting at the pen tip. Average radii of tracks of the moving pen tip, metacarpal head of the index finger, and distal end of the forearm during writing. Correlation coefficients of the instantaneous speed-time graph of the pen tip with that of the index finger and with that of the distal forearm during writing. Time for writing with the hemiparetic right hand was longer than that with the unaffected left hand (P=.05 approximately .03), while it was shorter in healthy control subjects (P=.07 approximately .05). In contrast with the left-hand writing, the track radius of the pen tip of the right-hand writing in patients with hemiparesis with normal joint position sense was significantly larger than that of the finger or distal forearm (P=.01). The finding was the same as in the young and elderly control subjects. This right-left difference disappeared in the patients with hemiparesis with position sense impairment. The correlation coefficient of speed between the pen tip and the finger was larger in right-hand than left-hand writing in the control and sensory-normative patients with hemiparesis even though the difference was significant only in the healthy elderly subjects (P=.03). Irrespective of the right or left hand use, the correlation coefficient between the pen tip and the finger or distal forearm significantly increased as the character size increased (P=.03 approximately 6 x10(-6)) in all subjects and patients. However, this size-related difference was less significant in the patients with sensory impairment. The characteristics of handwriting movement by the dominant hand were preserved in patients with mild dominant-hand hemiparesis when joint position sense was normative but were lost in those with position sense impairment.

Dataglove measurement of joint angles in sign language handshapes

PubMed Central

Eccarius, Petra; Bour, Rebecca; Scheidt, Robert A.

2012-01-01

In sign language research, we understand little about articulatory factors involved in shaping phonemic boundaries or the amount (and articulatory nature) of acceptable phonetic variation between handshapes. To date, there exists no comprehensive analysis of handshape based on the quantitative measurement of joint angles during sign production. The purpose of our work is to develop a methodology for collecting and visualizing quantitative handshape data in an attempt to better understand how handshapes are produced at a phonetic level. In this pursuit, we seek to quantify the flexion and abduction angles of the finger joints using a commercial data glove (CyberGlove; Immersion Inc.). We present calibration procedures used to convert raw glove signals into joint angles. We then implement those procedures and evaluate their ability to accurately predict joint angle. Finally, we provide examples of how our recording techniques might inform current research questions. PMID:23997644

Ultrasound of the fingers for human identification using biometrics.

PubMed

Narayanasamy, Ganesh; Fowlkes, J Brian; Kripfgans, Oliver D; Jacobson, Jon A; De Maeseneer, Michel; Schmitt, Rainer M; Carson, Paul L

2008-03-01

It was hypothesized that the use of internal finger structure as imaged using commercially available ultrasound (US) scanners could act as a supplement to standard methods of biometric identification, as well as a means of assessing physiological and cardiovascular status. Anatomical structures in the finger including bone contour, tendon and features along the interphalangeal joint were investigated as potential biometric identifiers. Thirty-six pairs of three-dimensional (3D) gray-scale images of second to fourth finger (index, middle and ring) data taken from 20 individuals were spatially registered using MIAMI-Fuse software developed at our institution and also visually matched by four readers. The image-based registration met the criteria for matching successfully in 14 out of 15 image pairs on the same individual and did not meet criteria for matching in any of the 12 image pairs from different subjects, providing a sensitivity and specificity of 0.93 and 1.00, respectively. Visual matching of all image pairs by four readers yielded 96% successful match. Power Doppler imaging was performed to calculate the change in color pixel density due to physical exercise as a surrogate of stress level and to provide basic physiological information. (E-mail: gnarayan@umich.edu).

Effect of skin-transmitted vibration enhancement on vibrotactile perception.

PubMed

Tanaka, Yoshihiro; Ueda, Yuichiro; Sano, Akihito

2015-06-01

Vibration on skin elicited by the mechanical interaction of touch between the skin and an object propagates to skin far from the point of contact. This paper investigates the effect of skin-transmitted vibration on vibrotactile perception. To enhance the transmission of high-frequency vibration on the skin, stiff tape was attached to the skin so that the tape covered the bottom surface of the index finger from the periphery of the distal interphalangeal joint to the metacarpophalangeal joint. Two psychophysical experiments with high-frequency vibrotactile stimuli of 250 Hz were conducted. In the psychophysical experiments, discrimination and detection thresholds were estimated and compared between conditions of the presence or the absence of the tape (normal bare finger). A method of limits was applied for the detection threshold estimation, and the discrimination task using a reference stimulus and six test stimuli with different amplitudes was applied for the discrimination threshold estimation. The stimulation was given to bare fingertips of participants. Result showed that the detection threshold was enhanced by attaching the tape, and the discrimination threshold enhancement by attaching the tape was confirmed for participants who have relatively large discrimination threshold under normal bare finger. Then, skin-transmitted vibration was measured with an accelerometer with the psychophysical experiments. Result showed that the skin-transmitted vibration when the tape was attached to the skin was larger than that when normal bare skin. There is a correlation between the increase in skin-transmitted vibration and the enhancement of the discrimination threshold.

Detection of rheumatoid arthritis in humans by fluorescence imaging

NASA Astrophysics Data System (ADS)

Ebert, Bernd; Dziekan, Thomas; Weissbach, Carmen; Mahler, Marianne; Schirner, Michael; Berliner, Birgitt; Bauer, Daniel; Voigt, Jan; Berliner, Michael; Bahner, Malte L.; Macdonald, Rainer

2010-02-01

The blood pool agent indo-cyanine green (ICG) has been investigated in a prospective clinical study for detection of rheumatoid arthritis using fluorescence imaging. Temporal behavior as well as spatial distribution of fluorescence intensity are suited to differentiate healthy and inflamed finger joints after i.v. injection of an ICG bolus.

LASER BIOLOGY AND MEDICINE: Light scattering study of rheumatoid arthritis

NASA Astrophysics Data System (ADS)

Beuthan, J.; Netz, U.; Minet, O.; Klose, Annerose D.; Hielscher, A. H.; Scheel, A.; Henniger, J.; Müller, G.

2002-11-01

The distribution of light scattered by finger joints is studied in the near-IR region. It is shown that variations in the optical parameters of the tissue (scattering coefficient μs, absorption coefficient μa, and anisotropy factor g) depend on the presence of the rheumatoid arthritis (RA). At the first stage, the distribution of scattered light was measured in diaphanoscopic experiments. The convolution of a Gaussian error function with the scattering phase function proved to be a good approximation of the data obtained. Then, a new method was developed for the reconstruction of distribution of optical parameters in the finger cross section. Model tests of the quality of this reconstruction method show good results.

Virtual three-dimensional blackboard: three-dimensional finger tracking with a single camera

NASA Astrophysics Data System (ADS)

Wu, Andrew; Hassan-Shafique, Khurram; Shah, Mubarak; da Vitoria Lobo, N.

2004-01-01

We present a method for three-dimensional (3D) tracking of a human finger from a monocular sequence of images. To recover the third dimension from the two-dimensional images, we use the fact that the motion of the human arm is highly constrained owing to the dependencies between elbow and forearm and the physical constraints on joint angles. We use these anthropometric constraints to derive a 3D trajectory of a gesticulating arm. The system is fully automated and does not require human intervention. The system presented can be used as a visualization tool, as a user-input interface, or as part of some gesture-analysis system in which 3D information is important.

Decoding of human hand actions to handle missing limbs in neuroprosthetics.

PubMed

Belić, Jovana J; Faisal, A Aldo

2015-01-01

The only way we can interact with the world is through movements, and our primary interactions are via the hands, thus any loss of hand function has immediate impact on our quality of life. However, to date it has not been systematically assessed how coordination in the hand's joints affects every day actions. This is important for two fundamental reasons. Firstly, to understand the representations and computations underlying motor control "in-the-wild" situations, and secondly to develop smarter controllers for prosthetic hands that have the same functionality as natural limbs. In this work we exploit the correlation structure of our hand and finger movements in daily-life. The novelty of our idea is that instead of averaging variability out, we take the view that the structure of variability may contain valuable information about the task being performed. We asked seven subjects to interact in 17 daily-life situations, and quantified behavior in a principled manner using CyberGlove body sensor networks that, after accurate calibration, track all major joints of the hand. Our key findings are: (1) We confirmed that hand control in daily-life tasks is very low-dimensional, with four to five dimensions being sufficient to explain 80-90% of the variability in the natural movement data. (2) We established a universally applicable measure of manipulative complexity that allowed us to measure and compare limb movements across tasks. We used Bayesian latent variable models to model the low-dimensional structure of finger joint angles in natural actions. (3) This allowed us to build a naïve classifier that within the first 1000 ms of action initiation (from a flat hand start configuration) predicted which of the 17 actions was going to be executed-enabling us to reliably predict the action intention from very short-time-scale initial data, further revealing the foreseeable nature of hand movements for control of neuroprosthetics and tele operation purposes. (4) Using the Expectation-Maximization algorithm on our latent variable model permitted us to reconstruct with high accuracy (<5-6° MAE) the movement trajectory of missing fingers by simply tracking the remaining fingers. Overall, our results suggest the hypothesis that specific hand actions are orchestrated by the brain in such a way that in the natural tasks of daily-life there is sufficient redundancy and predictability to be directly exploitable for neuroprosthetics.

Design and Fabrication of a Universal Soft Gripper

NASA Astrophysics Data System (ADS)

Sabzehzar, Amin

Inspired from nature, soft robots capable of actively tuning their mechanical rigidity can rapidly transition between a broad range of motor tasks, from lifting heavy loads to dexterous manipulation of delicate objects. Reversible rigidity tuning also enables soft robotic actuators to reroute their internal loading and alter their mode of deformation in response to intrinsic activation. In this study, we demonstrate this principle with a three-fingered pneumatic gripper that contains programmable ligaments that change stiness when activated with electrical current. The ligaments are composed of a conductive thermoplastic elastomer composite that reversibly softens under resistive heating. Depending on which ligaments are activated, the gripper will bend inward to pick up an object, bend laterally to twist it, or bend outward to release it. Each finger consists of three PDMS phalanges that are attached with two Ecoflex joints. Three ligaments (strips of a cPBE-PDMS composite layer) are attached along the finger and are stimulated with electricity individually. When the high pressure air is injected in the hollow middle part of the finger, the finger will be bent in the opposite direction of the stimulated cPBE-PDMS element (softer wall). This enables the gripper's fingers to grab and twist objects with dierent sizes and shapes. All of the gripper motions are generated with a single pneumatic source of pressure and are controlled with an electrical board. The ability to incorporate electrically programmable ligaments in pneumatic or hydraulic actuators has the potential to enhance versatility and reduce dependency on tubing and valves. In this study, an activation/deactivation cycle can be completed within 15 s.

Collagenase Treatment in Dupuytren Contractures: A Review of the Current State Versus Future Needs.

PubMed

Degreef, Ilse

2016-06-01

Dupuytren disease is highly prevalent and the finger contractures can be very extensile, compromising the patients' hand function. To restore full function, contractures have been addressed by cutting the causative strands for nearly 200 years, ever since Baron Guillaume Dupuytren demonstrated his technique at the beginning of the nineteenth century. Surgery can be minimal (fasciotomy) or quite invasive (fasciectomy and even skin replacement). However, in the last decade translational research has introduced the non-surgical technique of enzymatic fasciotomy with collagenase injections. Now, finger contractures can be released with single injections on monthly intervals, to address one joint contracture at a time. However, in hands affected with Dupuytren contractures to the extent that the patient calls for treatment, most often more than one joint is involved. In surgical treatment options all contracted joints are addressed in a single procedure. Nevertheless, extensile surgery withholds inherent risks of complications and intense rehabilitation. Today, the minimally-invasive method with enzymatic fasciotomy by collagenase injection has demonstrated reliable outcomes with few morbidities and early recovery. However, single-site injection is todays' standard procedure and multiple joints are addressed in several sessions with monthly intervals. This triggers a longer recovery and treatment burden in severely affected hands even though surgery is avoided. Therefore, further treatment modalities of collagenase use are explored. Adjustments in the treatment regimes' flexibility and collagenase injections addressing more than one joint contracture simultaneously will improve the burden of multiple sessions and, therefore, enzymatic fasciotomy may become the preferred method in more extensile Dupuytren contractures. In this independent review, the challenge of Dupuytren disease affecting a single versus multiple joints is presented. The pros and cons of collagenase use are weighed, founded by the available scientific background. The demands and options for collagenase in future treatment regimens for extensile Dupuytren contractures are discussed.

Development of a parametric kinematic model of the human hand and a novel robotic exoskeleton.

PubMed

Burton, T M W; Vaidyanathan, R; Burgess, S C; Turton, A J; Melhuish, C

2011-01-01

This paper reports the integration of a kinematic model of the human hand during cylindrical grasping, with specific focus on the accurate mapping of thumb movement during grasping motions, and a novel, multi-degree-of-freedom assistive exoskeleton mechanism based on this model. The model includes thumb maximum hyper-extension for grasping large objects (~> 50 mm). The exoskeleton includes a novel four-bar mechanism designed to reproduce natural thumb opposition and a novel synchro-motion pulley mechanism for coordinated finger motion. A computer aided design environment is used to allow the exoskeleton to be rapidly customized to the hand dimensions of a specific patient. Trials comparing the kinematic model to observed data of hand movement show the model to be capable of mapping thumb and finger joint flexion angles during grasping motions. Simulations show the exoskeleton to be capable of reproducing the complex motion of the thumb to oppose the fingers during cylindrical and pinch grip motions. © 2011 IEEE

An Architecture for Measuring Joint Angles Using a Long Period Fiber Grating-Based Sensor

PubMed Central

Perez-Ramirez, Carlos A.; Almanza-Ojeda, Dora L.; Guerrero-Tavares, Jesus N.; Mendoza-Galindo, Francisco J.; Estudillo-Ayala, Julian M.; Ibarra-Manzano, Mario A.

2014-01-01

The implementation of signal filters in a real-time form requires a tradeoff between computation resources and the system performance. Therefore, taking advantage of low lag response and the reduced consumption of resources, in this article, the Recursive Least Square (RLS) algorithm is used to filter a signal acquired from a fiber-optics-based sensor. In particular, a Long-Period Fiber Grating (LPFG) sensor is used to measure the bending movement of a finger. After that, the Gaussian Mixture Model (GMM) technique allows us to classify the corresponding finger position along the motion range. For these measures to help in the development of an autonomous robotic hand, the proposed technique can be straightforwardly implemented on real time platforms such as Field Programmable Gate Array (FPGA) or Digital Signal Processors (DSP). Different angle measurements of the finger's motion are carried out by the prototype and a detailed analysis of the system performance is presented. PMID:25536002

Upper limb congenital muscular hypertrophy and aberrant muscle syndrome in children.

PubMed

Dahan, Emmanuel; Chaves, Camilo; Bachy, Manon; Fitoussi, Frank

2018-01-01

Congenital muscle hypertrophy of the upper limb is a very rare condition with unknown aetiology. This descriptive observational and retrospective series included eight children followed by a multidisciplinary team from 2005 to 2017. The diagnosis was based on a cluster of clinical and radiological characteristics after elimination of differential diagnoses. Patients were categorized according to: anomalies of the wrist, anomalies of long fingers of intrinsic or extrinsic origin; and anomalies of the thumb with or without first web space contracture. Treatment begins in young children with hand orthoses to limit muscle contraction and joint malposition. The purpose of surgical treatment was to release contractures and to restore muscle balance through, in the main, finger intrinsic releases and first web releases. At the 2-year follow-up, we found that limited surgical procedures improved finger, thumb and wrist positions. We conclude that muscle hypertrophy is the main cause of deformity and that selective releases of contracted musculo-tendinous units and skin lengthening are effective. IV.

Rehabilitation for bilateral amputation of fingers

USGS Publications Warehouse

Stapanian, Martin A.; Stapanian, Adrienne M.P.; Staley, Keith E.

2010-01-01

We describe reconstructive surgeries, therapy, prostheses, and adaptations for a patient who experienced bilateral amputation of all five fingers of both hands through the proximal phalanges in January 1992. The patient made considerable progress in the use of his hands in the 10 mo after amputation, including nearly a 120% increase in the active range of flexion of metacarpophalangeal joints. In late 1992 and early 1993, the patient had "on-top plasty" surgeries, in which the index finger remnants were transferred onto the thumb stumps, performed on both hands. The increased web space and functional pinch resulting from these procedures made many tasks much easier. The patient and occupational therapists set challenging goals at all times. Moreover, the patient was actively involved in the design and fabrication of all prostheses and adaptations or he developed them himself. Although he was discharged from occupational therapy in 1997, the patient continues to actively find new solutions for prehension and grip strength 18 yr after amputation.

Ultrasound disease activity of bilateral wrist and finger joints at three months reflects the clinical response at six months of patients with rheumatoid arthritis treated with biologic disease-modifying anti-rheumatic drugs.

PubMed

Kawashiri, Shin-Ya; Nishino, Ayako; Shimizu, Toshimasa; Umeda, Masataka; Fukui, Shoichi; Nakashima, Yoshikazu; Suzuki, Takahisa; Koga, Tomohiro; Iwamoto, Naoki; Ichinose, Kunihiro; Tamai, Mami; Nakamura, Hideki; Origuchi, Tomoki; Aoyagi, Kiyoshi; Kawakami, Atsushi

2017-03-01

We evaluated whether the early responsiveness of ultrasound synovitis can predict the clinical response in rheumatoid arthritis (RA) patients treated with biologic disease-modifying anti-rheumatic drugs (bDMARDs). Articular synovitis was assessed by ultrasound at 22 bilateral wrist and finger joints in 39 RA patients treated with bDMARDs. Each joint was assigned a gray-scale (GS) and power Doppler (PD) score from 0 to 3, and the sum of the GS or PD scores was considered to represent the ultrasound disease activity. We investigated the correlation of the change in ultrasound disease activity at three months with the EULAR response criteria at six months. GS and PD scores were significantly decreased at three months (p < 0.0001). The % changes of the GS and PD scores at three months were significantly higher at six months in moderate and good responders compared with non-responders (p < 0.05). These tendencies were numerically more prominent if clinical response was set as good responder or Disease Activity Score 28 remission. Poor improvement of ultrasound synovitis scores had good predictive value for non-responders at six months. The responsiveness of ultrasound disease activity is considered to predict further clinical response in RA patients treated with bDMARDs.

An EMG Interface for the Control of Motion and Compliance of a Supernumerary Robotic Finger

PubMed Central

Hussain, Irfan; Spagnoletti, Giovanni; Salvietti, Gionata; Prattichizzo, Domenico

2016-01-01

In this paper, we propose a novel electromyographic (EMG) control interface to control motion and joints compliance of a supernumerary robotic finger. The supernumerary robotic fingers are a recently introduced class of wearable robotics that provides users additional robotic limbs in order to compensate or augment the existing abilities of natural limbs without substituting them. Since supernumerary robotic fingers are supposed to closely interact and perform actions in synergy with the human limbs, the control principles of extra finger should have similar behavior as human’s ones including the ability of regulating the compliance. So that, it is important to propose a control interface and to consider the actuators and sensing capabilities of the robotic extra finger compatible to implement stiffness regulation control techniques. We propose EMG interface and a control approach to regulate the compliance of the device through servo actuators. In particular, we use a commercial EMG armband for gesture recognition to be associated with the motion control of the robotic device and surface one channel EMG electrodes interface to regulate the compliance of the robotic device. We also present an updated version of a robotic extra finger where the adduction/abduction motion is realized through ball bearing and spur gears mechanism. We have validated the proposed interface with two sets of experiments related to compensation and augmentation. In the first set of experiments, different bimanual tasks have been performed with the help of the robotic device and simulating a paretic hand since this novel wearable system can be used to compensate the missing grasping abilities in chronic stroke patients. In the second set, the robotic extra finger is used to enlarge the workspace and manipulation capability of healthy hands. In both sets, the same EMG control interface has been used. The obtained results demonstrate that the proposed control interface is intuitive and can successfully be used, not only to control the motion of a supernumerary robotic finger but also to regulate its compliance. The proposed approach can be exploited also for the control of different wearable devices that has to actively cooperate with the human limbs. PMID:27891088

Sports Injury-Related Fingers and Thumb Deformity Due to Tendon or Ligament Rupture.

PubMed

Bai, Rong-Jie; Zhang, Hui-Bo; Zhan, Hui-Li; Qian, Zhan-Hua; Wang, Nai-Li; Liu, Yue; Li, Wen-Ting; Yin, Yu-Ming

2018-05-05

Hand injuries are very common in sports, such as skiing and ball sports. One of the major reasons causing hand and finger deformity is due to ligament and tendon injury. The aim of this study was to investigate if the high-resolution 3T magnetic resonance imaging (MRI) can demonstrate the complex anatomy of the fingers and thumb, especially the tendons and ligaments, and provide the accurate diagnosis of clinically important fingers and thumbs deformity due to ligamentous and tendinous injuries during sport activities. Sixteen fresh un-embalmed cadaveric hands were harvested from eight cadavers. A total of 20 healthy volunteers' hands and 44 patients with fingers or thumb deformity due to sports-related injuries were included in this study. All subjects had MR examination with T1-weighted images and proton density-weighted imaging with fat suppression (PD FS) in axial, coronal, and sagittal plane, respectively. Subsequently, all 16 cadaveric hands were sliced into 2-mm thick slab with a band saw (six in coronal plane, six in sagittal plane, and four in axial plane). The correlation of anatomic sections and the MRI characteristics of tendons of fingers and the ulnar collateral ligament (UCL) at the metacarpal phalangeal joint (MCPJ) of thumb between 20 healthy volunteers and 44 patients (confirmed by surgery) were analyzed. The normal ligaments and tendons in 16 cadaveric hands and 20 volunteers' hands showed uniform low-signal intensity on all the sequences of the MRI. Among 44 patients with tendinous and ligamentous injuries in the fingers or thumb, 12 cases with UCL injury at MCPJ of the thumb (Stener lesion = 8 and non-Stener lesion = 4), 6 cases with the central slip injury, 12 cases with terminal tendon injury, and 14 cases with flexor digitorum profundus injury. The ligaments and tendons disruption manifested as increased signal intensity and poor definition, discontinuity, and heterogeneous signal intensity of the involved ligaments and tendons. Sports injury-related fingers and thumb deformity are relatively common. MRI is an accurate method for evaluation of the anatomy and pathologic conditions of the fingers and thumb. It is a useful tool for accurate diagnosis of the sports-related ligaments and tendons injuries in hand.

Extensor Tendon Instability Due to Sagittal Band Injury in a Martial Arts Athlete: A Case Report.

PubMed

Kochevar, Andrew; Rayan, Ghazi

2017-03-01

A Taekwondo participant sustained a hand injury from punching an opponent that resulted in painful instability of the ring finger extensor digitorum communis tendon due to sagittal band damage. His symptoms resolved after reconstructive surgery on the sagittal band (SB) with stabilization of the extensor tendon over the metacarpophalangeal joint.

Conformational Changes in the Carpus During Finger Traps Distraction

PubMed Central

Leventhal, Evan L.; Moore, Douglas C.; Akelman, Edward; Wolfe, Scott W.; Crisco, Joseph J.

2010-01-01

Introduction Wrist distraction is a common treatment maneuver used clinically for the reduction of distal radial fractures and mid-carpal dislocations. Wrist distraction is also required during wrist arthroscopy to access the radiocarpal joint and has been used as a test for scapholunate ligament injury. However, the effect of a distraction load on the normal wrist has not been well studied. The purpose of this study was to measure the 3-D conformational changes of the carpal bones in the normal wrist as a result of a static distractive load. Methods The dominant wrists of 14 healthy volunteers were scanned using computed tomography at rest and during application of 98N of distraction. Load was applied using finger traps and volunteers were encouraged to relax their forearm muscles and to allow distraction of the wrist. The motions of the bones in the wrist were tracked between the unloaded and loaded trial using markerless bone registration. The average displacement vector of each bone was calculated relative to the radius as well as the interbone distances for 20 bone-bone interactions. Joint separation was estimated at the radiocarpal, midcarpal and carpal-metacarpal joints in the direction of loading using the radius, lunate, capitate and 3rd metacarpal. Results With loading, the distance between the radius and 3rd metacarpal increased an average of 3.3±3.1mm in the direction of loading. This separation was primarily located in the axial direction at the radiocarpal (1.0±1.0mm) and midcarpal (2.0±1.7mm) joints. There were minimal changes in the transverse direction within the distal row, although the proximal row narrowed by 0.98±0.7mm. Distraction between the radius and scaphoid (2.5±2.2mm) was 2.4 times greater than between the radius and lunate (1.0±1.0mm). Conclusions Carpal distraction has a significant effect on the conformation of the carpus, especially at the radiocarpal and midcarpal joints. In the normal wrist, external traction causes twice as much distraction at the lunocapitate joint than at the radiolunate joint. PMID:20141894

Conformational changes in the carpus during finger trap distraction.

PubMed

Leventhal, Evan L; Moore, Douglas C; Akelman, Edward; Wolfe, Scott W; Crisco, Joseph J

2010-02-01

Wrist distraction is a common treatment maneuver used clinically for the reduction of distal radial fractures and midcarpal dislocations. Wrist distraction is also required during wrist arthroscopy to access the radiocarpal joint and has been used as a test for scapholunate ligament injury. However, the effect of a distraction load on the normal wrist has not been well studied. The purpose of this study was to measure the three-dimensional conformational changes of the carpal bones in the normal wrist as a result of a static distractive load. Using computed tomography, the dominant wrists of 14 healthy volunteers were scanned at rest and during application of 98 N of distraction. Load was applied using finger traps, and volunteers were encouraged to relax their forearm muscles and to allow distraction of the wrist. The motions of the bones in the wrist were tracked between the unloaded and loaded trial using markerless bone registration. The average displacement vector of each bone relative to the radius was calculated, as were the interbone distances for 20 bone-bone interactions. Joint separation was estimated at the radiocarpal, midcarpal, and carpometacarpal joints in the direction of loading using the radius, lunate, capitate, and third metacarpal. With loading, the distance between the radius and third metacarpal increased an average of 3.3 mm +/- 3.1 in the direction of loading. This separation was primarily in the axial direction at the radiocarpal (1.0 mm +/- 1.0) and midcarpal (2.0 mm +/- 1.7) joints. There were minimal changes in the transverse direction within the distal row, although the proximal row narrowed by 0.98 mm +/- 0.7. Distraction between the radius and scaphoid (2.5 mm +/- 2.2) was 2.4 times greater than that between the radius and lunate (1.0 mm +/- 1.0). Carpal distraction has a significant (p < .01) effect on the conformation of the carpus, especially at the radiocarpal and midcarpal joints. In the normal wrist, external traction causes twice as much distraction at the lunocapitate joint than at the radiolunate joint. Copyright 2010. Published by Elsevier Inc.

Why borrow from Peter when Paul can afford it? Reverse homodigital artery flap for fingertip reconstruction

PubMed Central

Sundaramurthy, Narayanamurthy; Venkata Mahipathy, Surya Rao Rao; Durairaj, Alagar Raja

2017-01-01

Background: Fingertip injuries that are complicated by pulp loss, bone or tendon exposure will need a flap cover. Cross finger flap is commonly used to cover such defects. However, patients are apprehensive about injuring the uninjured finger as a donor site. Reverse homodigital artery flap (RHAF) can provide reliable vascularised cover to such defects. Aims: This study aims to assess the functional and aesthetic outcomes along with the patient satisfaction of RHAFs done for fingertip defects. Materials and Methods: RHAFs done in 18 patients operated between August 2015 and October 2016 were retrospectively analysed on flap survival, sensory recovery, range of movements, hypersensitivity, cold intolerance, flexion contracture and donor site morbidity. Results: Seventeen of the 18 flaps done survived completely. One flap had partial necrosis of 3 mm that healed conservatively. Middle finger of the right hand was the most commonly injured finger. Touch, pain and pressure sensations recovered in 8–12 weeks. Two-point discrimination was 4.5 mm at 6 months. The deficit of 5° s was present at distal interphalangeal joint during active flexion at 6 months. Cold intolerance and flexion contracture were not seen and 2 instances of hypersensitivity at 2 months got cured conservatively after 4 months. Overall satisfaction of patients was 8/10. Conclusion: RHAF provides single staged well-vascularised cover for fingertip injuries with good sensory recovery without damaging the adjacent uninjured finger. Hence, it can be a reliable flap for fingertip reconstruction in selected cases. PMID:29343895

Design-validation of a hand exoskeleton using musculoskeletal modeling.

PubMed

Hansen, Clint; Gosselin, Florian; Ben Mansour, Khalil; Devos, Pierre; Marin, Frederic

2018-04-01

Exoskeletons are progressively reaching homes and workplaces, allowing interaction with virtual environments, remote control of robots, or assisting human operators in carrying heavy loads. Their design is however still a challenge as these robots, being mechanically linked to the operators who wear them, have to meet ergonomic constraints besides usual robotic requirements in terms of workspace, speed, or efforts. They have in particular to fit the anthropometry and mobility of their users. This traditionally results in numerous prototypes which are progressively fitted to each individual person. In this paper, we propose instead to validate the design of a hand exoskeleton in a fully digital environment, without the need for a physical prototype. The purpose of this study is thus to examine whether finger kinematics are altered when using a given hand exoskeleton. Therefore, user specific musculoskeletal models were created and driven by a motion capture system to evaluate the fingers' joint kinematics when performing two industrial related tasks. The kinematic chain of the exoskeleton was added to the musculoskeletal models and its compliance with the hand movements was evaluated. Our results show that the proposed exoskeleton design does not influence fingers' joints angles, the coefficient of determination between the model with and without exoskeleton being consistently high (R 2 ¯=0.93) and the nRMSE consistently low (nRMSE¯ = 5.42°). These results are promising and this approach combining musculoskeletal and robotic modeling driven by motion capture data could be a key factor in the ergonomics validation of the design of orthotic devices and exoskeletons prior to manufacturing. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nikolaus Rüdinger (1832-1896), His Description of Joint Innervation in 1857, and the History of Surgical Joint Denervation.

PubMed

Gohritz, Andreas; Kaiser, Erich; Guggenheim, Merlin; Dellon, Arnold Lee

2018-01-01

 Selective joint denervation has become a reliable palliative treatment, especially for painful joints in the upper and lower extremity.  This article highlights the life and work of Nikolaus Rüdinger (1832-1896) who first described joint innervation which became the basis of later techniques of surgical joint denervation. The historical evolution of this method is outlined.  Rüdinger made a unique career from apprentice barber to military surgeon and anatomy professor in Munich, Germany. His first description of articular innervation of temporomandibular, shoulder, elbow, wrist, finger, sacroiliac, hip, knee, ankle, foot, and toe joints in 1857 stimulated the subsequent history of surgical joint denervation. Comparing his investigations with modern joint denervation methods, developed by pioneers like Albrecht Wilhelm or A. Lee Dellon, shows his great exactitude and anatomical correspondence despite different current terminology. Clinical series of modern surgical joint denervations reveal success rates of up to 80% with reliable long-term results.  The history of joint denervation with Rüdinger as its important protagonist offers inspiring insights into the evolution of surgical techniques and exemplifies the value of descriptive functional anatomy, even if surgical application may not have been realized until a century later. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Dynamic optical imaging of vascular and metabolic reactivity in rheumatoid joints.

PubMed

Lasker, Joseph M; Fong, Christopher J; Ginat, Daniel T; Dwyer, Edward; Hielscher, Andreas H

2007-01-01

Dynamic optical imaging is increasingly applied to clinically relevant areas such as brain and cancer imaging. In this approach, some external stimulus is applied and changes in relevant physiological parameters (e.g., oxy- or deoxyhemoglobin concentrations) are determined. The advantage of this approach is that the prestimulus state can be used as a reference or baseline against which the changes can be calibrated. Here we present the first application of this method to the problem of characterizing joint diseases, especially effects of rheumatoid arthritis (RA) in the proximal interphalangeal finger joints. Using a dual-wavelength tomographic imaging system together with previously implemented model-based iterative image reconstruction schemes, we have performed initial dynamic imaging case studies on a limited number of healthy volunteers and patients diagnosed with RA. Focusing on three cases studies, we illustrated our major finds. These studies support our hypothesis that differences in the vascular reactivity exist between affected and unaffected joints.

Protective effect of sensory denervation in inflammatory arthritis (evidence of regulatory neuroimmune pathways in the arthritic joint)

PubMed Central

Kane, D; Lockhart, J; Balint, P; Mann, C; Ferrell, W; McInnes, I

2005-01-01

Case report: The patient developed arthritis mutilans in all digits of both hands with the exception of the left 4th finger, which had prior sensory denervation following traumatic nerve dissection. Plain radiography, ultrasonography and nerve conduction studies of the hands confirmed the absence of articular disease and sensory innervation in the left 4th digit. Methods: This relationship between joint innervation and joint inflammation was investigated experimentally by prior surgical sensory denervation of the medial aspect of the knee in six Wistar rats in which carrageenan induced arthritis was subsequently induced. Prior sensory denervation—with preservation of muscle function—prevented the development of inflammatory arthritis in the denervated knee. Discussion: Observations in human and animal inflammatory arthritis suggest that regulatory neuroimmune pathways in the joint are an important mechanism that modulates the clinical expression of inflammatory arthritis. PMID:15155371

Electro-mechanical heat switch for cryogenic applications

DOEpatents

van den Berg, Marcel L.; Batteux, Jan D.; Labov, Simon E.

2003-01-01

A heat switch includes two symmetric jaws. Each jaw is comprised of a link connected at a translatable joint to a flexible arm. Each arm rotates about a fixed pivot, and has an articulated end including a thermal contact pad connected to a heat sink. The links are joined together at a translatable main joint. To close the heat switch, a closing solenoid is actuated and forces the main joint to an over-center position. This movement rotates the arms about their pivots, respectively, forces each of them into a stressed configuration, and forces the thermal contact pads towards each other and into compressive contact with a cold finger. The closing solenoid is then deactivated. The heat switch remains closed due to a restoring force generated by the stressed configuration of each arm, until actuation of an opening solenoid returns the main joint to its starting open-switch position.

In-game Management of Common Joint Dislocations

PubMed Central

Skelley, Nathan W.; McCormick, Jeremy J.; Smith, Matthew V.

2014-01-01

Context: Sideline management of sports-related joint dislocations often places the treating medical professional in a challenging position. These injuries frequently require prompt evaluation, diagnosis, reduction, and postreduction management before they can be evaluated at a medical facility. Our objective is to review the mechanism, evaluation, reduction, and postreduction management of sports-related dislocations to the shoulder, elbow, finger, knee, patella, and ankle joints. Evidence Acquisition: A literature review was performed using the PubMed database to evaluate previous and current publications focused on joint dislocations. This review focused on articles published between 1980 and 2013. Study Design: Clinical review. Level of Evidence: Level 4. Results: The clinician should weigh the benefits and risks of on-field reduction based on their knowledge of the injury and the presence of associated injuries. Conclusion: When properly evaluated and diagnosed, most sports-related dislocations can be reduced and initially managed at the game. PMID:24790695

[Application of distal palm perforator mini-flap in repair of scar contracture of digital web-spaces].

PubMed

Zhou, Xiao; Xu, Yajun; Rui, Yongjun; Shou, Kuishui; Yao, Qun

2011-02-01

To discuss the effectiveness of distal palm perforator mini-flap in the treatment of scar contracture of digital web-spaces. Between August 2008 and March 2010, 6 cases of scar contracture of digital web-spaces were treated, including 4 males and 2 females and aging 16-68 years (mean, 45 years). The causes were burn injury, twisting injury, and crush injury in 2 cases, respectively. The disease duration was from 3 months to 3 years. The affected digital web-spaces were from index finger to middle finger in 2 cases, from middle finger to ring finger in 3 cases, and from ring finger to small finger in 1 case. The maximum abduction degree of digital web-spaces was 5-10 degrees. The sizes and the depths of reshape of digital web-spaces disappeared. The defect size ranged from 20 mm x 8 mm to 30 mm x 13 mm after opening digital web-spaces. The size of the distal palm perforator mini-flap ranged from 25 mm x 10 mm to 35 mm x 15 mm. The donor sites were sutured directly. All 6 flaps survived and got primary healing. Incisions at donor sites healed by first intention. All patients were followed up 6-12 months. The reconstructed digital web-spaces had good appearance and soft texture. The range of motion of metacarpophalangeal joint was normal. The sizes and the depths of reshape of digital web-spaces were similar to normal ones. The maximum abduction degree of digital web-spaces was 40-60 degrees. There was no scar contracture of incision of palm. The shape of flaps and function of the fingers were satisfactory after 6-12 months of follow-up. It is an ideal method to treat scar contracture of digital web-spaces with distal palm perforator mini-flap.

Fluorescence optical imaging and 3T-MRI for detection of synovitis in patients with rheumatoid arthritis in comparison to a composite standard of reference.

PubMed

Thuermel, Klaus; Neumann, Jan; Jungmann, Pia M; Schäffeler, Christoph; Waldt, Simone; Heinze, Alexander; Beckmann, Alexander; Hauser, Christine; Hasenau, Anna-Lena; Wildgruber, Moritz; Clotten, Sigrun; Sievert, Matti; Haller, Bernhard; Woertler, Klaus; Harasser, Norbert; Rummeny, Ernst J; Meier, Reinhard

2017-05-01

To address whether Indocyanine Green (ICG) enhanced fluorescence optical imaging (FOI) is more sensitive than magnetic resonance imaging (MRI) in the detection of synovitis of the wrist and finger joints in rheumatoid arthritis and to analyze the performance of FOI depending on the grade of synovitis. Twenty patients with highly active rheumatoid arthritis (mean DAS28-ESR 5.25±1.0) and thirteen healthy volunteers underwent clinical examination, FOI and contrast-enhanced 3T-MRI. Joints were rated by three independent readers semiquantitatively (grade 0-3: no, low, moderate and high grade synovitis) and compared to a semiquantitative composite standard of reference (cSOR, grade 0-3) that incorporated clinical parameters, FOI and MRI results. 2.868 evaluations in 956 joints were performed. FOI had an overall sensitivity of 57.3% and a specificity of 92.1%, whereas MRI had a sensitivity of 89.2% and a specificity of 92.6%. The sensitivity of FOI increased with the degree of synovitis to 65.0% for moderate and severe synovitis (specificity 88.1%) and 76,3% for severe synovitis (specificity 80.5%). The performance of FOI decreased with the degree of synovitis with false negative results predominantly for mild (156/343, 45.5%) and moderate (160/343, 46.6%) synovitis and false positive FOI evaluations predominantly based on weak (grade 1) signals (133/163, 81,6%). FOI has a lower sensitivity than 3T-MRI in the detection of synovitis of the hand and finger joints. The diagnostic performance of FOI decreases with the degree of synovitis and with the strength of FOI signals. Copyright © 2017 Elsevier B.V. All rights reserved.

Postural and Intention Tremors: A Detailed Clinical Study of Essential Tremor vs. Parkinson’s Disease

PubMed Central

Sternberg, Eliezer J.; Alcalay, Roy N.; Levy, Oren A.; Louis, Elan D.

2013-01-01

Background: An estimated 30–50% of essential tremor (ET) diagnoses are incorrect, and the true diagnosis in those patients is often Parkinson’s disease (PD) or other tremor disorders. There are general statements about the tremor in these ET and PD, but published data on the more subtle characteristics of tremor are surprisingly limited. Postural tremor may occur in both disorders, adding to the difficulty. There are several anecdotal impressions regarding specific features of postural tremor in ET vs. PD, including joint distribution (e.g., phalanges, metacarpal-phalangeal joints, wrist), tremor directionality (e.g., flexion-extension vs. pronation-supination), and presence of intention tremor. However, there is little data to support these impressions. Methods: In this cross-sectional study, 100 patients (ET, 50 PD) underwent detailed videotaped neurological examinations. Arm tremor was rated by a movement disorder neurologist who assessed severity and directionality across multiple joints. Results: During sustained arm extension, ET patients exhibited more wrist than metacarpal-phalangeal and phalangeal joint tremor than did PD patients (p < 0.001), and more wrist flexion-extension tremor than wrist pronation-supination tremor (p < 0.001). During the finger-nose-finger maneuver, intention tremor was present in approximately one in four (28%) ET patients vs. virtually none (4%) of the Parkinson’s patients (p < 0.001). Conclusions: We evaluated the location, severity, and directionality of postural tremor in ET and PD, and the presence of intention tremor, observing several clinical differences. We hope that detailed phenomenological data on tremor in ET and PD will help practicing physicians delineate the two diseases. PMID:23717300

The Neurological-Impress Method of Teaching Reading.

ERIC Educational Resources Information Center

Partridge, Susan

In the neurological impress method the teacher sits slightly behind the child, a book is held jointly, and the teacher and child read aloud simultaneously with the teacher directing his/her voice into the child's ear as the child slides a finger along each line following the words as they are spoken. No attempt is made to teach sounds or word…

Structure design for a Two-DoF myoelectric prosthetic hand to realize basic hand functions in ADLs.

PubMed

Hoshigawa, Suguru; Jiang, Yinlai; Kato, Ryu; Morishita, Soichiro; Nakamura, Tatsuhiro; Yabuki, Yoshiko; Yokoi, Hiroshi

2015-01-01

Prosthetic hands are desired by those who have lost a hand or both hands not only for decoration but also for the functions to help them with their activities of daily living (ADL). Prosthetic robotic hands that are developed to fully realize the function of a human hand are usually too expensive to be economically available, difficult to operate and maintain, or over heavy for longtime wearing. The aim of this study is therefore to develop a simplified prosthetic hand (sim-PH), which is to be controlled by myoelectric signals from the user, to realize the most important grasp motions in ADL by trading off the cost and performance. This paper reports the structure design of a two-DoF sim-PH with two motors to drive the CM joint of the thumb and the interlocked MP joints of the other four fingers. In order to optimize the structure, the model of the sim-PH was proposed based on which 7 sim-PHs with different structural parameters were manufactured and tested in a pick-and-place experiment. Correspondence analysis of the experimental results clarified the relationship between the hand functions and the shapes of fingers.

Learning algorithms for human-machine interfaces.

PubMed

Danziger, Zachary; Fishbach, Alon; Mussa-Ivaldi, Ferdinando A

2009-05-01

The goal of this study is to create and examine machine learning algorithms that adapt in a controlled and cadenced way to foster a harmonious learning environment between the user and the controlled device. To evaluate these algorithms, we have developed a simple experimental framework. Subjects wear an instrumented data glove that records finger motions. The high-dimensional glove signals remotely control the joint angles of a simulated planar two-link arm on a computer screen, which is used to acquire targets. A machine learning algorithm was applied to adaptively change the transformation between finger motion and the simulated robot arm. This algorithm was either LMS gradient descent or the Moore-Penrose (MP) pseudoinverse transformation. Both algorithms modified the glove-to-joint angle map so as to reduce the endpoint errors measured in past performance. The MP group performed worse than the control group (subjects not exposed to any machine learning), while the LMS group outperformed the control subjects. However, the LMS subjects failed to achieve better generalization than the control subjects, and after extensive training converged to the same level of performance as the control subjects. These results highlight the limitations of coadaptive learning using only endpoint error reduction.

Learning Algorithms for Human–Machine Interfaces

PubMed Central

Fishbach, Alon; Mussa-Ivaldi, Ferdinando A.

2012-01-01

The goal of this study is to create and examine machine learning algorithms that adapt in a controlled and cadenced way to foster a harmonious learning environment between the user and the controlled device. To evaluate these algorithms, we have developed a simple experimental framework. Subjects wear an instrumented data glove that records finger motions. The high-dimensional glove signals remotely control the joint angles of a simulated planar two-link arm on a computer screen, which is used to acquire targets. A machine learning algorithm was applied to adaptively change the transformation between finger motion and the simulated robot arm. This algorithm was either LMS gradient descent or the Moore–Penrose (MP) pseudoinverse transformation. Both algorithms modified the glove-to-joint angle map so as to reduce the endpoint errors measured in past performance. The MP group performed worse than the control group (subjects not exposed to any machine learning), while the LMS group outperformed the control subjects. However, the LMS subjects failed to achieve better generalization than the control subjects, and after extensive training converged to the same level of performance as the control subjects. These results highlight the limitations of coadaptive learning using only endpoint error reduction. PMID:19203886

A prospective study on the risk of glove fingertip contamination during draping in joint replacement surgery.

PubMed

Makki, D; Deierl, K; Pandit, A; Trakru, S

2014-09-01

The aim of this prospective study was to investigate the risk of contamination of surgical gloves during preparation and draping in joint replacement surgery. During 46 hip and knee replacement procedures, the gloves of orthopaedic consultants (n=5) and registrars (n=3) were assessed for contamination immediately after draping by impression of gloved fingers on blood agar. Contamination was evaluated by the surgeon's grade, the type of procedure, the role of the assistant and the dominance of the hand. A total of 125 pairs of top gloves were examined (79 pairs from registrars and 46 pairs from consultants). Bacterial contamination was isolated on 19 pairs (15.2%) (16 pairs from registrars and 3 pairs from consultants, p=0.04). Coagulase negative staphylococci were the main isolates and contamination was considered low in all cases (1-5 colonies). Contamination was seen more on the dominant hand (16 gloves from dominant hands and 6 from non-dominant hands, p=0.04), on the index finger and thumb. More contaminated gloves were seen in hip arthroplasty procedures (16 pairs from total hip replacements vs 3 pairs from total knee replacements, p=0.02). Contamination of glove fingertips during draping in joint replacement procedures is more likely to occur among junior surgeons, in hip rather than knee arthroplasty procedures and on the dominant hand. It is therefore essential that surgeons of different grades replace gloves used in draping to avoid exposing patients to the risk of infection.

Comparative study of functional and aesthetically outcomes of reverse digital artery and reverse dorsal homodigital island flaps for fingertip repair.

PubMed

Chen, Q Z; Sun, Y C; Chen, J; Kong, J; Gong, Y P; Mao, T

2015-11-01

This retrospective study was designed to compare functional and cosmetic outcomes of the reverse digital artery island flap and reverse dorsal homodigital island flap in fingertip repair. A total of 23 patients were followed for 24 to 30 months. The reverse digital artery island flap was used in 12 patients, and reverse dorsal homodigital island flap in another 11 patients. Flap sensibility was assessed using the Semmes-Weinstein monofilament test and static 2-point discrimination test. Patient satisfaction, active motion of the finger joints, complications and cold intolerance were evaluated. The static 2-point discrimination and Michigan Hand Outcomes Questionnaire (appearance) of the fingers treated with a reverse digital artery flap were significantly better than those with a reverse dorsal homodigital flap. The static 2-point discrimination of the skin-grafted donor sides after dorsal homodigital flap were poorer than that in the contralateral finger. No significant differences were found between the two flaps for pressure or touch sensibility, active ranges of digital motion, complications and cold intolerance. III. © The Author(s) 2015.

Treatment of chronic extensor tendons lesions of the fingers.

PubMed

Bellemère, P

2015-09-01

Chronic finger extensor apparatus injuries are the result of the initial acute treatment having failed or being flawed. Because of their chronic nature, these injuries present various amounts of tendon retraction, tendon callus lengthening, peritendinous scar adhesions, static and dynamic imbalances with the flexor apparatus and intrinsic muscles, and joint contractures. This article will review the anatomy of the extensor mechanism and then will outline by location, the various clinical pictures that are secondary to chronic tendon injury. The clinical presentation of these injuries can be highly variable but their symptomatology and treatment are very specific. Of the possible therapeutic strategies for chronic mallet finger with or without associated swan-neck deformity, chronic boutonniere deformity, chronic sagittal band injuries, old ruptures on the dorsum of the wrist and traumatic defects in multiple tissues, conservative treatment is often the main element. Secondary surgical repair is not free of complications, and the results are often lacking. Rehabilitation and orthotic bracing are an integral part of the management of these injuries, no matter which treatment method is being considered. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Extra-articular fractures of the digital metacarpals and phalanges of the long fingers.

PubMed

Le Nen, D

2014-02-01

Metacarpal and phalangeal fractures of the long fingers are the result of trauma occurring under extremely varied circumstances. As a consequence, the clinical presentation varies greatly, with every bone and joint potentially being involved. Each step of their treatment is crucial, although the benign appearance of these injuries can lead to steps being missed: diagnostic phase with clinical examination and radiographs; therapeutic phase where the most suitable treatment is chosen, which combines mobilization of the digital chains as soon as possible and in every patient; follow-up phase with regular monitoring to detect any complications, especially secondary displacement, and verify that good progress is being made during rehabilitation. The goal of any fracture treatment is to preserve or restore the anatomy, with the emphasis here being on the stability and mobility of the digital chains. The potential progression towards serious functional sequelae (pain, instability or stiffness in hand) and the resulting significant socio-economic repercussions must be at the forefront of a surgeon's mind early on during the initial care of any finger or hand trauma. Copyright © 2014. Published by Elsevier SAS.

Wearable Wide-Range Strain Sensors Based on Ionic Liquids and Monitoring of Human Activities

PubMed Central

Zhang, Shao-Hui; Wang, Feng-Xia; Li, Jia-Jia; Peng, Hong-Dan; Yan, Jing-Hui; Pan, Ge-Bo

2017-01-01

Wearable sensors for detection of human activities have encouraged the development of highly elastic sensors. In particular, to capture subtle and large-scale body motion, stretchable and wide-range strain sensors are highly desired, but still a challenge. Herein, a highly stretchable and transparent stain sensor based on ionic liquids and elastic polymer has been developed. The as-obtained sensor exhibits impressive stretchability with wide-range strain (from 0.1% to 400%), good bending properties and high sensitivity, whose gauge factor can reach 7.9. Importantly, the sensors show excellent biological compatibility and succeed in monitoring the diverse human activities ranging from the complex large-scale multidimensional motions to subtle signals, including wrist, finger and elbow joint bending, finger touch, breath, speech, swallow behavior and pulse wave. PMID:29135928

On-top plasty using a free metacarpal head graft for lengthening of proximal phalanx in symbrachydactyly--a case report.

PubMed

Iba, Kousuke; Wada, Takuro; Yamashita, Toshihiko

2013-01-01

A three-year old patient with symbrachydactyly (didactyly type) presented with a little finger that was too short to allow pinching and consisting of a floppy soft-tissue envelope with hypoplastic phalanges, although the thumb was functional. As the proximal phalanx was too small to permit distraction lengthening or conventional bone grafting, on-top plasty using a 4th metacarpal graft with a cartilage head was undertaken for lengthening the proximal phalanx of the little finger for pinch reconstruction. At ten weeks after surgery, the patient achieved satisfactory pinch function due to the lengthened and bone-stabilised postoperative digit and reconstruction of functional proximal interphalangeal joint. In addition, the grafted metacarpal demonstrated satisfactory bone growth throughout the six-year follow-up period.

Fluorescence optical imaging and musculoskeletal ultrasonography in juvenile idiopathic polyarticular disease before and during antirheumatic treatment - a multicenter non-interventional diagnostic evaluation.

PubMed

Klein, Ariane; Just, Georg Werner; Werner, Stephanie Gabriele; Oommen, Prasad T; Minden, Kirsten; Becker, Ingrid; Langer, Hans-Eckhard; Klee, Dirk; Horneff, Gerd

2017-06-30

Valid detection of inflamed joints is essential for correct classification, therapeutic decisions, prognosis and assessment of treatment efficacy in juvenile idiopathic arthritis (JIA). Fluorescence optical imaging (FOI) enables visualization of inflammation in arthritis of finger and hand joints and might be used for monitoring. A 24-week observational study in polyarticular JIA patients newly starting treatment with methotrexate or an approved biologic was performed in three centers. Patients were evaluated clinically, by gray-scale ultrasonography (GSUS), power-Doppler ultrasonography (PDUS) and FOI at baseline, week 12 and week 24. Of 37 patients enrolled, 24 patients started methotrexate and 13 patients a biologic for the first time (etanercept n = 11, adalimumab and tocilizumab n = 1 each). Mean JADAS 10 decreased significantly from 17.7 at baseline to 12.2 and 7.2 at week 12 and 24 respectively. PedACR 30/50/70/100 response rates at week 24 were 85%/73%/50%/27%. The total number of clinically active joints in hand and fingers at baseline/week 12/week 24 was 262 (23.6%)/162 (16.4%)/162 (9.0%). By GSUS, at baseline/week 12/week 24, 192 (19.4%)/135 (16.1%)/83 (11.5%) joints showed effusions and 186 (18.8%)/107 (12.7%)/69 (9.6%) showed synovial thickening, and by PDUS 68 (6.9%)/15 (1.8%)/36 (5%) joints showed hyperperfusion. Any sign of arthritis was detected by US in a total of 243 joints (24.5%) at baseline, 161 joints (19.2%) at week 12 and 123 joints (17%) at week 24. By FOI at baseline/week 12/week 24, 430 (38.7%)/280 (29.2%)/215 (27.6%) showed a signal enhancement in at least one phase. Summarizing all three points of time, the highest numbers of signals were detected by FOI with 32% of joints, especially in phase 2, while by US 20.7% and by clinical examination 17.5% of joints were active. A high number of joints (21.1%) had FOI signals but were inactive by clinical examination. A total 20.1% of joints with signals in FOI did not show effusion, synovial thickening or hyperperfusion by US. Because of the high number of negative results, specificity of FOI compared with clinical examination/US/PD was high (84-95%), and sensitivity was only moderate. FOI and US could detect clinical but also subclinical inflammation. FOI detected subclinical inflammation to a higher extent than US. Improvement upon treatment with either methotrexate or a biologic can be visualized by FOI and US. Deutsches Register Klinischer Studien DRKS00011579 . Registered 10 January 2017.

Improving Kinematic Accuracy of Soft Wearable Data Gloves by Optimizing Sensor Locations

PubMed Central

Kim, Dong Hyun; Lee, Sang Wook; Park, Hyung-Soon

2016-01-01

Bending sensors enable compact, wearable designs when used for measuring hand configurations in data gloves. While existing data gloves can accurately measure angular displacement of the finger and distal thumb joints, accurate measurement of thumb carpometacarpal (CMC) joint movements remains challenging due to crosstalk between the multi-sensor outputs required to measure the degrees of freedom (DOF). To properly measure CMC-joint configurations, sensor locations that minimize sensor crosstalk must be identified. This paper presents a novel approach to identifying optimal sensor locations. Three-dimensional hand surface data from ten subjects was collected in multiple thumb postures with varied CMC-joint flexion and abduction angles. For each posture, scanned CMC-joint contours were used to estimate CMC-joint flexion and abduction angles by varying the positions and orientations of two bending sensors. Optimal sensor locations were estimated by the least squares method, which minimized the difference between the true CMC-joint angles and the joint angle estimates. Finally, the resultant optimal sensor locations were experimentally validated. Placing sensors at the optimal locations, CMC-joint angle measurement accuracies improved (flexion, 2.8° ± 1.9°; abduction, 1.9° ± 1.2°). The proposed method for improving the accuracy of the sensing system can be extended to other types of soft wearable measurement devices. PMID:27240364

A hybrid BMI-based exoskeleton for paresis: EMG control for assisting arm movements

NASA Astrophysics Data System (ADS)

Kawase, Toshihiro; Sakurada, Takeshi; Koike, Yasuharu; Kansaku, Kenji

2017-02-01

Objective. Brain-machine interface (BMI) technologies have succeeded in controlling robotic exoskeletons, enabling some paralyzed people to control their own arms and hands. We have developed an exoskeleton asynchronously controlled by EEG signals. In this study, to enable real-time control of the exoskeleton for paresis, we developed a hybrid system with EEG and EMG signals, and the EMG signals were used to estimate its joint angles. Approach. Eleven able-bodied subjects and two patients with upper cervical spinal cord injuries (SCIs) performed hand and arm movements, and the angles of the metacarpophalangeal (MP) joint of the index finger, wrist, and elbow were estimated from EMG signals using a formula that we derived to calculate joint angles from EMG signals, based on a musculoskeletal model. The formula was exploited to control the elbow of the exoskeleton after automatic adjustments. Four able-bodied subjects and a patient with upper cervical SCI wore an exoskeleton controlled using EMG signals and were required to perform hand and arm movements to carry and release a ball. Main results. Estimated angles of the MP joints of index fingers, wrists, and elbows were correlated well with the measured angles in 11 able-bodied subjects (correlation coefficients were 0.81  ±  0.09, 0.85  ±  0.09, and 0.76  ±  0.13, respectively) and the patients (e.g. 0.91  ±  0.01 in the elbow of a patient). Four able-bodied subjects successfully positioned their arms to adequate angles by extending their elbows and a joint of the exoskeleton, with root-mean-square errors  <6°. An upper cervical SCI patient, empowered by the exoskeleton, successfully carried a ball to a goal in all 10 trials. Significance. A BMI-based exoskeleton for paralyzed arms and hands using real-time control was realized by designing a new method to estimate joint angles based on EMG signals, and these may be useful for practical rehabilitation and the support of daily actions.

A hybrid BMI-based exoskeleton for paresis: EMG control for assisting arm movements.

PubMed

Kawase, Toshihiro; Sakurada, Takeshi; Koike, Yasuharu; Kansaku, Kenji

2017-02-01

Brain-machine interface (BMI) technologies have succeeded in controlling robotic exoskeletons, enabling some paralyzed people to control their own arms and hands. We have developed an exoskeleton asynchronously controlled by EEG signals. In this study, to enable real-time control of the exoskeleton for paresis, we developed a hybrid system with EEG and EMG signals, and the EMG signals were used to estimate its joint angles. Eleven able-bodied subjects and two patients with upper cervical spinal cord injuries (SCIs) performed hand and arm movements, and the angles of the metacarpophalangeal (MP) joint of the index finger, wrist, and elbow were estimated from EMG signals using a formula that we derived to calculate joint angles from EMG signals, based on a musculoskeletal model. The formula was exploited to control the elbow of the exoskeleton after automatic adjustments. Four able-bodied subjects and a patient with upper cervical SCI wore an exoskeleton controlled using EMG signals and were required to perform hand and arm movements to carry and release a ball. Estimated angles of the MP joints of index fingers, wrists, and elbows were correlated well with the measured angles in 11 able-bodied subjects (correlation coefficients were 0.81  ±  0.09, 0.85  ±  0.09, and 0.76  ±  0.13, respectively) and the patients (e.g. 0.91  ±  0.01 in the elbow of a patient). Four able-bodied subjects successfully positioned their arms to adequate angles by extending their elbows and a joint of the exoskeleton, with root-mean-square errors  <6°. An upper cervical SCI patient, empowered by the exoskeleton, successfully carried a ball to a goal in all 10 trials. A BMI-based exoskeleton for paralyzed arms and hands using real-time control was realized by designing a new method to estimate joint angles based on EMG signals, and these may be useful for practical rehabilitation and the support of daily actions.

Quantitative assessment of joint position sense recovery in subacute stroke patients: a pilot study.

PubMed

Kattenstroth, Jan-Christoph; Kalisch, Tobias; Kowalewski, Rebecca; Tegenthoff, Martin; Dinse, Hubert R

2013-11-01

To assess joint position sense performance in subacute stroke patients using a novel quantitative assessment. Proof-of-principle pilot study with a group of subacute stroke patients. Assessment at baseline and after 2 weeks of intervention. Additional data for a healthy age-matched control group. Ten subacute stroke patients (aged 65.41 years (standard deviation 2.5), 4 females, 2.3 weeks (standard deviation 0.2)) post-stroke receiving in-patient standard rehabilitation and repetitive electrical stimulation of the affected hand. Joint position sense was assessed based on the ability of correctly perceiving the opening angles of the finger joints. Patients had to report size differences of polystyrene balls of various sizes, whilst the balls were enclosed simultaneously by the affected and the non-affected hands. A total of 21 pairwise size comparisons was used to quantify joint position performance. After 2 weeks of therapeutic intervention a significant improvement in joint position sense performance was observed; however, the performance level was still below that of a healthy control group. The results indicate high feasibility and sensitivity of the joint position test in subacute stroke patients. Testing allowed quantification of both the deficit and the rehabilitation outcome.

Sensing human hand motions for controlling dexterous robots

NASA Technical Reports Server (NTRS)

Marcus, Beth A.; Churchill, Philip J.; Little, Arthur D.

1988-01-01

The Dexterous Hand Master (DHM) system is designed to control dexterous robot hands such as the UTAH/MIT and Stanford/JPL hands. It is the first commercially available device which makes it possible to accurately and confortably track the complex motion of the human finger joints. The DHM is adaptable to a wide variety of human hand sizes and shapes, throughout their full range of motion.

FingerScanner: Embedding a Fingerprint Scanner in a Raspberry Pi.

PubMed

Sapes, Jordi; Solsona, Francesc

2016-02-06

Nowadays, researchers are paying increasing attention to embedding systems. Cost reduction has lead to an increase in the number of platforms supporting the operating system Linux, jointly with the Raspberry Pi motherboard. Thus, embedding devices on Raspberry-Linux systems is a goal in order to make competitive commercial products. This paper presents a low-cost fingerprint recognition system embedded into a Raspberry Pi with Linux.

Design and Preliminary Feasibility Study of a Soft Robotic Glove for Hand Function Assistance in Stroke Survivors

PubMed Central

Yap, Hong Kai; Lim, Jeong Hoon; Nasrallah, Fatima; Yeow, Chen-Hua

2017-01-01

Various robotic exoskeletons have been proposed for hand function assistance during activities of daily living (ADL) of stroke survivors. However, traditional exoskeletons involve the use of complex rigid systems that impede the natural movement of joints, and thus reduce the wearability and cause discomfort to the user. The objective of this paper is to design and evaluate a soft robotic glove that is able to provide hand function assistance using fabric-reinforced soft pneumatic actuators. These actuators are made of silicone rubber which has an elastic modulus similar to human tissues. Thus, they are intrinsically soft and compliant. Upon air pressurization, they are able to support finger range of motion (ROM) and generate the desired actuation of the finger joints. In this work, the soft actuators were characterized in terms of their blocked tip force, normal and frictional grip force outputs. Combining the soft actuators and flexible textile materials, a soft robotic glove was developed for grasping assistance during ADL for stroke survivors. The glove was evaluated on five healthy participants for its assisted ROM and grip strength. Pilot test was performed in two stroke survivors to evaluate the efficacy of the glove in assisting functional grasping activities. Our results demonstrated that the actuators designed in this study could generate desired force output at a low air pressure. The glove had a high kinematic transparency and did not affect the active ROM of the finger joints when it was being worn by the participants. With the assistance of the glove, the participants were able to perform grasping actions with sufficient assisted ROM and grip strength, without any voluntary effort. Additionally, pilot test on stroke survivors demonstrated that the patient's grasping performance improved with the presence and assistance of the glove. Patient feedback questionnaires also showed high level of patient satisfaction and comfort. In conclusion, this paper has demonstrated the possibility of using soft wearable exoskeletons that are more wearable, lightweight, and suitable to be used on a daily basis for hand function assistance of stroke survivors during activities of daily living. PMID:29062267

Hand anthropometry of Indian women.

PubMed

Nag, Anjali; Nag, P K; Desai, Hina

2003-06-01

Data on the physical dimension of the hand of Indian women are scanty. This information is necessary to ascertain human-machine compatibility in the design of manual systems for the bare and gloved hand, such as design and sizing of hand tools, controls, knobs and other applications in different kinds of precision and power grips. The present study was undertaken to generate hand anthropometric data of 95 women, working in informal industries (beedi, agarbatti and garment making). Fifty one hand measurements of the right hand (lengths, breadths, circumferences, depths, spreads and clearances of hand and fingers) were taken, using anthropometric sliding and spreading calipers, measuring tape and handgrip strength dynamometer. The data were statistically analyzed to determine the normality of data and the percentile values of different hand dimensions, and simple and multiple regression analysis were done to determine better predictors of hand length and grip strength. The hand breadths, circumferences and depths were approximately normally distributed, with some deviation in case of the finger lengths. Hand length was significantly correlated with the fist, wrist and finger circumferences. The fist and wrist circumferences, in combination, were better predictors of hand length. The hand lengths, breadths and depths, including finger joints of the Indian women studied were smaller than those of American, British and West Indian women. The hand circumferences of the Indian women were also smaller than the American women. Grip strengths of Indian women (20.36 +/- 3.24 kg) were less than those of American, British and West Indian women. Grip strength was found to be statistically significant with hand dimensions, such as hand height perpendicular to wrist crease (digit 5), proximal interphalangeal joint breadth (digit 3) and hand spread across wedge 1. The women who are forced to frequently use cutters, strippers and other tools, which are not optimally designed to their hand dimensions and strength range, might have higher prevalence of clinical symptoms and disorders of the hand. In view of the human hand-tool interface requirements, the present data on Indian women would be useful for ergo-design applications of hand tools and devices.

Correlation between extension-block K-wire insertion angle and postoperative extension loss in mallet finger fracture.

PubMed

Lee, S K; Kim, Y H; Moon, K H; Choy, W S

2018-02-01

Extension-block pinning represents a simple and reliable surgical technique. Although this procedure is commonly performed successfully, some patients develop postoperative extension loss. To date, the relationship between extension-block Kirschner wire (K-wire) insertion angle and postoperative extension loss in mallet finger fracture remains unclear. We aimed to clarify this relationship and further evaluate how various operative and non-operative factors affect postoperative extension loss after extension-block pinning for mallet finger fracture. A retrospective study was conducted to investigate a relationship between extension block K-wire insertion angle and postoperative extension loss. The inclusion criteria were: (1) a dorsal intra-articular fracture fragment involving 30% of the base of the distal phalanx with or without volar subluxation of the distal phalanx; and (2) <3 weeks delay from the injury without treatment. Extension-block K-wire insertion angle and fixation angle of the distal interphalangeal (DIP) joint were assessed using lateral radiograph at immediate postoperative time. Postoperative extension loss was assessed by using lateral radiograph at latest follow-up. Extension-block K-wire insertion angle was defined as the acute angle between extension block K-wire and longitudinal axis of middle phalangeal head. DIP joint fixation angle was defined as the acute angle between the distal phalanx and middle phalanx longitudinal axes. Seventy-five patients were included. The correlation analysis revealed that extension-block K-wire insertion angle had a negative correlation with postoperative extension loss, whereas fracture size and time to operation had a positive correlation (correlation coefficient for extension block K-wire angle: -0.66, facture size: +0.67, time to operation: +0.60). When stratifying patients in terms of negative and positive fixation angle of the DIP joint, the independent t-test showed that mean postoperative extension loss is -3.67° and +4.54° (DIP joint fixation angles of <0° and ≥0°, respectively, P=0.024). When stratifying patients in terms of extension-block K-wire insertion angle (30°, 30°-40°, >40°), ANOVA showed significantly less postoperative extension loss for higher insertion angles (>40°) than for medium insertion angles (30°-40°). Mean postoperative extension loss difference between higher insertion angle (>40°) and medium insertion angle (30°-40°) was 11° (P=0.002). Using an insertion angle of the extension-block K-wire of 40°-45° and a slightly hyperextended position of the DIP joint may help reducing postoperative extension loss. Therapeutic level III. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

An under-actuated origami gripper with adjustable stiffness joints for multiple grasp modes

NASA Astrophysics Data System (ADS)

Firouzeh, Amir; Paik, Jamie

2017-05-01

Under-actuated robots offer multiple degrees of freedom without much added complexity to the actuation and control. Utilizing adjustable stiffness joints in these robots allows us to control their stable configurations and their mode of interaction with the environment. In this paper, we present the design of tendon-driven robotic origami (robogami) joints with adjustable stiffness. The proposed designs allow us to place joints along any direction in the plane of the robot and in the normal direction to the plane. The layer-by-layer manufacturing of robogamis facilitates the design and manufacturing of robots with different arrangement of joints for different applications. We use thermally activated shape memory polymer to control the joint stiffness. The manufacturing of the polymer layer is compatible with the layer-by-layer manufacturing process of the robogamis which results in scalable and customizable robots. To demonstrate, we prototyped an under-actuated gripper with three fingers and only one input actuation. The grasp mode of the gripper is set by adjusting the configuration of the locked joints and modulating the stiffness of the active joints. We present a model to estimate the configuration and the contact forces of the gripper at different settings that will assist us in design and control of future generation of under-actuated robogamis.

Identification of inflammation sites in arthritic joints using hyperspectral imaging

NASA Astrophysics Data System (ADS)

Paluchowski, Lukasz A.; Milanic, Matija; Bjorgan, Asgeir; Grandaunet, Berit; Dhainaut, Alvilde; Hoff, Mari; Randeberg, Lise L.

2014-03-01

Inflammatory arthritic diseases have prevalence between 2 and 3% and may lead to joint destruction and deformation resulting in a loss of function. Patient's quality of life is often severely affected as the disease attacks hands and finger joints. Pathology involved in arthritis includes angiogenesis, hyper-vascularization, hyper-metabolism and relative hypoxia. We have employed hyperspectral imaging to study the hemodynamics of affected- and non-affected joints and tissue. Two hyperspectral, push-broom cameras were used (VNIR-1600, SWIR-320i, Norsk Elektro Optikk AS, Norway). Optical spectra (400nm - 1700nm) of high spectral resolution were collected from 15 patients with visible symptoms of arthritic rheumatic diseases in at least one joint. The control group consisted of 10 healthy individuals. Concentrations of dominant chromophores were calculated based on analytical calculations of light transport in tissue. Image processing was used to analyze hyperspectral data and retrieve information, e.g. blood concentration and tissue oxygenation maps. The obtained results indicate that hyperspectral imaging can be used to quantify changes within affected joints and surrounding tissue. Further improvement of this method will have positive impact on diagnosis of arthritic joints at an early stage. Moreover it will enable development of fast, noninvasive and noncontact diagnostic tool of arthritic joints

Joint-specific risk of impaired function in fibrodysplasia ossificans progressiva (FOP).

PubMed

Pignolo, Robert J; Durbin-Johnson, Blythe P; Rocke, David M; Kaplan, Frederick S

2018-04-01

Fibrodysplasia ossificans progressiva (FOP) causes progressive disability due to heterotopic ossification from episodic flare-ups. Using data from 500 FOP patients (representing 63% of all known patients world-wide), age- and joint-specific risks of new joint involvement were estimated using parametric and nonparametric statistical methods. Compared to data from a 1994 survey of 44 individuals with FOP, our current estimates of age- and joint-specific risks of new joint involvement are more accurate (narrower confidence limits), based on a wider range of ages, and have less bias due to its greater comprehensiveness (captures over three-fifths of the known FOP patients worldwide). For the neck, chest, abdomen, and upper back, the estimated hazard decreases over time. For the jaw, lower back, shoulder, elbow, wrist, fingers, hip, knee, ankle, and foot, the estimated hazard increases initially then either plateaus or decreases. At any given time and for any anatomic site, the data indicate which joints are at risk. This study of approximately 63% of the world's known population of FOP patients provides a refined estimate of risk for new involvement at any joint at any age, as well as the proportion of patients with uninvolved joints at any age. Importantly, these joint-specific survival curves can be used to facilitate clinical trial design and to determine if potential treatments can modify the predicted trajectory of progressive joint dysfunction. Copyright © 2017 Elsevier Inc. All rights reserved.

Biomechanical analyses of prolonged handwriting in subjects with and without perceived discomfort.

PubMed

Chang, Shao-Hsia; Chen, Chien-Liang; Yu, Nan-Ying

2015-10-01

Since wrist-joint position affects finger muscle length and grip strength, we studied its biomechanical relevance in prolonged handwriting. We recruited participants from young adults, aged 18-24, and separated them into control (n=22) and in-pain (n=18) groups, based whether or not they experience pain while handwriting. The participants then performed a writing task for 30 min on a computerized system which measured their wrist-joint angle and documented their handwriting kinematics. The in-pain group perceived more soreness and had a less-extended wrist joint, longer on-paper time, and slower stroke velocity compared to control group. There was no significant difference in handwriting speed and quality between the two groups. The wrist extension angle significantly correlated with perceived soreness. Ergonomic and biomechanical analyses provide important information about the handwriting process. Knowledge of pen tip movement kinematics and wrist-joint position can help occupational therapists plan treatment for individuals with handwriting induced pain. Copyright © 2015 Elsevier B.V. All rights reserved.

[Past, present and future of vascularised bone transfers in the hand and wrist].

PubMed

Allieu, Y

2010-12-01

The author specifies the aims and indications for simple or compound pedicle or free vascularised bone and bone and joint grafts (VBGs and VBJGs). He relates the history of VBGs whose indications for the wrist are often many and varied for the treatment of scaphoid non-union and Kienböch's disease. Within the hand the indication for compound VBGs is dominated by thumb reconstruction (skin and bone grafts). Compound VBGs and VBJGs used in an emergency for hand trauma, harvested from another irrecoverable long finger (bank finger) are extremely varied and adapted to each particular case. For secondary joint reconstruction in the adult, VBJGs must be discussed along with prosthetic arthroplasties (radio-carpal, lower radio-ulnar, trapezo-metacarpal, interphalangeal). For children VBJGs with an included growth plate maintain their indication. The immediate future of VBGs is that of a better knowledge of bone necrosis and bone innervation as well as an improvement in surgical techniques: microsurgery and robotics, mini-invasive surgery (wrist arthroscopy). The near future for VBGs is to control bone consolidation thanks to progress in the bio-engineering of bone tissue, which may make them obsolete and, for VBJGs, vascularised joint allografts, thanks to progress in immunosuppressant treatments. Although the immediate future and this near future may be envisaged according to the current advances, the same is not true for the distant future which remains totally unforeseeable, although this might involve regeneration and construction of organs by man himself. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

A prospective study on the risk of glove fingertip contamination during draping in joint replacement surgery

PubMed Central

Deierl, K; Pandit, A; Trakru, S

2014-01-01

Introduction The aim of this prospective study was to investigate the risk of contamination of surgical gloves during preparation and draping in joint replacement surgery. Methods During 46 hip and knee replacement procedures, the gloves of orthopaedic consultants (n=5) and registrars (n=3) were assessed for contamination immediately after draping by impression of gloved fingers on blood agar. Contamination was evaluated by the surgeon’s grade, the type of procedure, the role of the assistant and the dominance of the hand. Results A total of 125 pairs of top gloves were examined (79 pairs from registrars and 46 pairs from consultants). Bacterial contamination was isolated on 19 pairs (15.2%) (16 pairs from registrars and 3 pairs from consultants, p=0.04). Coagulase negative staphylococci were the main isolates and contamination was considered low in all cases (1–5 colonies). Contamination was seen more on the dominant hand (16 gloves from dominant hands and 6 from non-dominant hands, p=0.04), on the index finger and thumb. More contaminated gloves were seen in hip arthroplasty procedures (16 pairs from total hip replacements vs 3 pairs from total knee replacements, p=0.02). Conclusions Contamination of glove fingertips during draping in joint replacement procedures is more likely to occur among junior surgeons, in hip rather than knee arthroplasty procedures and on the dominant hand. It is therefore essential that surgeons of different grades replace gloves used in draping to avoid exposing patients to the risk of infection. PMID:25198974

Presence and Absence of Muscle Contraction Elicited by Peripheral Nerve Electrical Stimulation Differentially Modulate Primary Motor Cortex Excitability.

PubMed

Sasaki, Ryoki; Kotan, Shinichi; Nakagawa, Masaki; Miyaguchi, Shota; Kojima, Sho; Saito, Kei; Inukai, Yasuto; Onishi, Hideaki

2017-01-01

Modulation of cortical excitability by sensory inputs is a critical component of sensorimotor integration. Sensory afferents, including muscle and joint afferents, to somatosensory cortex (S1) modulate primary motor cortex (M1) excitability, but the effects of muscle and joint afferents specifically activated by muscle contraction are unknown. We compared motor evoked potentials (MEPs) following median nerve stimulation (MNS) above and below the contraction threshold based on the persistence of M-waves. Peripheral nerve electrical stimulation (PES) conditions, including right MNS at the wrist at 110% motor threshold (MT; 110% MNS condition), right MNS at the index finger (sensory digit nerve stimulation [DNS]) with stimulus intensity approximately 110% MNS (DNS condition), and right MNS at the wrist at 90% MT (90% MNS condition) were applied. PES was administered in a 4 s ON and 6 s OFF cycle for 20 min at 30 Hz. In Experiment 1 ( n = 15), MEPs were recorded from the right abductor pollicis brevis (APB) before (baseline) and after PES. In Experiment 2 ( n = 15), M- and F-waves were recorded from the right APB. Stimulation at 110% MNS at the wrist evoking muscle contraction increased MEP amplitudes after PES compared with those at baseline, whereas DNS at the index finger and 90% MNS at the wrist not evoking muscle contraction decreased MEP amplitudes after PES. M- and F-waves, which reflect spinal cord or muscular and neuromuscular junctions, did not change following PES. These results suggest that muscle contraction and concomitant muscle/joint afferent inputs specifically enhance M1 excitability.

Presence and Absence of Muscle Contraction Elicited by Peripheral Nerve Electrical Stimulation Differentially Modulate Primary Motor Cortex Excitability

PubMed Central

Sasaki, Ryoki; Kotan, Shinichi; Nakagawa, Masaki; Miyaguchi, Shota; Kojima, Sho; Saito, Kei; Inukai, Yasuto; Onishi, Hideaki

2017-01-01

Modulation of cortical excitability by sensory inputs is a critical component of sensorimotor integration. Sensory afferents, including muscle and joint afferents, to somatosensory cortex (S1) modulate primary motor cortex (M1) excitability, but the effects of muscle and joint afferents specifically activated by muscle contraction are unknown. We compared motor evoked potentials (MEPs) following median nerve stimulation (MNS) above and below the contraction threshold based on the persistence of M-waves. Peripheral nerve electrical stimulation (PES) conditions, including right MNS at the wrist at 110% motor threshold (MT; 110% MNS condition), right MNS at the index finger (sensory digit nerve stimulation [DNS]) with stimulus intensity approximately 110% MNS (DNS condition), and right MNS at the wrist at 90% MT (90% MNS condition) were applied. PES was administered in a 4 s ON and 6 s OFF cycle for 20 min at 30 Hz. In Experiment 1 (n = 15), MEPs were recorded from the right abductor pollicis brevis (APB) before (baseline) and after PES. In Experiment 2 (n = 15), M- and F-waves were recorded from the right APB. Stimulation at 110% MNS at the wrist evoking muscle contraction increased MEP amplitudes after PES compared with those at baseline, whereas DNS at the index finger and 90% MNS at the wrist not evoking muscle contraction decreased MEP amplitudes after PES. M- and F-waves, which reflect spinal cord or muscular and neuromuscular junctions, did not change following PES. These results suggest that muscle contraction and concomitant muscle/joint afferent inputs specifically enhance M1 excitability. PMID:28392766

Quantifying Forearm Muscle Activity during Wrist and Finger Movements by Means of Multi-Channel Electromyography

PubMed Central

Gazzoni, Marco; Celadon, Nicolò; Mastrapasqua, Davide; Paleari, Marco; Margaria, Valentina; Ariano, Paolo

2014-01-01

The study of hand and finger movement is an important topic with applications in prosthetics, rehabilitation, and ergonomics. Surface electromyography (sEMG) is the gold standard for the analysis of muscle activation. Previous studies investigated the optimal electrode number and positioning on the forearm to obtain information representative of muscle activation and robust to movements. However, the sEMG spatial distribution on the forearm during hand and finger movements and its changes due to different hand positions has never been quantified. The aim of this work is to quantify 1) the spatial localization of surface EMG activity of distinct forearm muscles during dynamic free movements of wrist and single fingers and 2) the effect of hand position on sEMG activity distribution. The subjects performed cyclic dynamic tasks involving the wrist and the fingers. The wrist tasks and the hand opening/closing task were performed with the hand in prone and neutral positions. A sensorized glove was used for kinematics recording. sEMG signals were acquired from the forearm muscles using a grid of 112 electrodes integrated into a stretchable textile sleeve. The areas of sEMG activity have been identified by a segmentation technique after a data dimensionality reduction step based on Non Negative Matrix Factorization applied to the EMG envelopes. The results show that 1) it is possible to identify distinct areas of sEMG activity on the forearm for different fingers; 2) hand position influences sEMG activity level and spatial distribution. This work gives new quantitative information about sEMG activity distribution on the forearm in healthy subjects and provides a basis for future works on the identification of optimal electrode configuration for sEMG based control of prostheses, exoskeletons, or orthoses. An example of use of this information for the optimization of the detection system for the estimation of joint kinematics from sEMG is reported. PMID:25289669

FingerScanner: Embedding a Fingerprint Scanner in a Raspberry Pi

PubMed Central

Sapes, Jordi; Solsona, Francesc

2016-01-01

Nowadays, researchers are paying increasing attention to embedding systems. Cost reduction has lead to an increase in the number of platforms supporting the operating system Linux, jointly with the Raspberry Pi motherboard. Thus, embedding devices on Raspberry-Linux systems is a goal in order to make competitive commercial products. This paper presents a low-cost fingerprint recognition system embedded into a Raspberry Pi with Linux. PMID:26861340

An experimentally based nonlinear viscoelastic model of joint passive moment.

PubMed

Esteki, A; Mansour, J M

1996-04-01

Previous investigations have not converged on a generally accepted model of the dissipative part of joint passive moment. To provide a basis for developing a model, a series of measurements were performed to characterize the passive moment at the metacarpophalangeal joint of the index finger. Two measurement procedures were used, one in moment relaxation over a range of fixed joint angles and the other at a series of constant joint velocities. Fung's quasi-linear viscoelastic theory motivated the development of the passive moment model. Using this approach, it was not necessary to make restrictive assumptions regarding the viscoelastic behavior of the passive moment. The generality of the formulation allowed specific functions to be chosen based on experimental data rather than finding coefficients which attempted to fit a preselected model of the data. It was shown that a nonlinear viscoelastic model described the passive stiffness. No significant frictional effects were found. Of particular importance was the nonlinear behavior of the dissipative part of the passive moment which was modeled by joint speed raised to a power less than one. This result could explain the differing findings among previous investigations, and may have important implications for control of limb movement.

Multispectral diffuse optical tomography of finger joints

NASA Astrophysics Data System (ADS)

Lighter, Daniel; Filer, Andrew; Dehghani, Hamid

2017-07-01

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by synovial inflammation. The current treatment paradigm for earlier, more aggressive therapy places importance on development of functional imaging modalities, capable of quantifying joint changes at the earliest stages. Diffuse optical tomography (DOT) has shown great promise in this regard, due to its cheap, non-invasive, non-ionizing and high contrast nature. Underlying pathological activity in afflicted joints leads to altered optical properties of the synovial region, with absorption and scattering increasing. Previous studies have used these optical changes as features for classifying diseased joints from healthy. Non-tomographic, single wavelength, continuous wave (CW) measurements of trans-illuminated joints have previously reported achieving this with specificity and sensitivity in the range 80 - 90% [1]. A single wavelength, frequency domain DOT system, combined with machine learning techniques, has been shown to achieve sensitivity and specificity in the range of 93.8 - 100% [2]. A CW system is presented here which collects data at 5 wavelengths, enabling reconstruction of pathophysiological parameters such as oxygenation and total hemoglobin, with the aim of identifying localized hypoxia and angiogenesis associated with inflammation in RA joints. These initial studies focus on establishing levels of variation in recovered parameters from images of healthy controls.

[Conservative treatment of metacarpal fracture].

PubMed

Prokop, A; Helling, H J; Kulus, S; Rehm, K E

2002-01-01

Conservative treatment of meatacarpale fracture is recommended if there are no joint displacement, rotation failures, displacement over 30 degrees ad axim and shortening over 5 mm. Operative procedures should be done in open fractures and serial of fractures of metacarpale bones. Early functionally treatment should be done in stable, not displaced fractures. Cast can be used only for a short time in full extended position of fingers and flexion in metacarpo-phalangeal joint in 60-90 degrees. Twin-tapes after reduction of edema allowed free range of motion by fixed rotation. Closed reduction of displaced fractures of fifth metacarpal bone (boxer's fracture) isn't successful. Cases with displacement over 30 degrees may be operatively treated by intramedullary stabilization.

[Treatment of metacarpal fractures].

PubMed

Prokop, A; Jubel, A; Helling, H J; Kulus, S; Rehm, K E

2002-09-01

Conservative treatment of metacarpal fractures is recommended if there is no joint displacement, malrotation, displacement of over 30 degrees ad axim and shortening of over 5 mm. Surgery should be performed in open fractures and serial fractures of metacarpal bone. Early functional treatment should be carried out in stable, not displaced fractures. A cast can be used for a short period in full extended position of fingers and flexion in metacarpo-phalangeal joint in 60 - 90 degrees. Twin-tape fixation allows functional treatment after soft-tissue swelling has disappeared. Closed reduction of displaced fractures of the fifth metacarpal bone (boxer's fracture) is not successful. Cases with displacement of over 30 degrees may be treated surgically by intramedullary stabilisation.

Hand function and quality of life before and after fasciectomy for Dupuytren contracture.

PubMed

Engstrand, Christina; Krevers, Barbro; Nylander, Göran; Kvist, Joanna

2014-07-01

To describe changes in joint motion, sensibility, and scar pliability and to investigate the patients' expectations, self-reported recovery, and satisfaction with hand function, disability, and quality of life after surgery and hand therapy for Dupuytren disease. This prospective cohort study collected measurements before surgery and 3, 6, and 12 months after surgery and hand therapy. Ninety patients with total active extension deficits of 60° or more from Dupuytren contracture were included. Outcomes measures were range of motion; sensibility; scar pliability; self-reported outcomes on expectations, recovery, and satisfaction with hand function; Disabilities of the Arm, Shoulder, and Hand scores; safety and social issues of hand function; physical activity habits; and quality of life with the Euroqol. The extension deficit decreased, and there was a transient decrease in active finger flexion during the first year after surgery. Sensibility remained unaffected. Generally, patients with surgery on multiple fingers had worse scar pliability. The majority of the patients had their expectations met, and at 6 months, 32% considered hand function as fully recovered, and 73% were satisfied with their hand function. Fear of hurting the hand and worry about not trusting the hand function were of greatest concern among safety and social issues. The Disability of the Arm, Shoulder, and Hand score and the Euroqol improved over time. After surgery and hand therapy, disability decreased independent of single or multiple operated fingers. The total active finger extension improved enough for the patients to reach a functional range of motion despite an impairment of active finger flexion still present 12 months after treatment. Therapeutic IV. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Optical HMI with biomechanical energy harvesters integrated in textile supports

NASA Astrophysics Data System (ADS)

De Pasquale, G.; Kim, SG; De Pasquale, D.

2015-12-01

This paper reports the design, prototyping and experimental validation of a human-machine interface (HMI), named GoldFinger, integrated into a glove with energy harvesting from fingers motion. The device is addressed to medical applications, design tools, virtual reality field and to industrial applications where the interaction with machines is restricted by safety procedures. The HMI prototype includes four piezoelectric transducers applied to the fingers backside at PIP (proximal inter-phalangeal) joints, electric wires embedded in the fabric connecting the transducers, aluminum case for the electronics, wearable switch made with conductive fabrics to turn the communication channel on and off, and a LED. The electronic circuit used to manage the power and to control the light emitter includes a diodes bridge, leveling capacitors, storage battery and switch made by conductive fabric. The communication with the machine is managed by dedicated software, which includes the user interface, the optical tracking, and the continuous updating of the machine microcontroller. The energetic benefit of energy harvester on the battery lifetime is inversely proportional to the activation time of the optical emitter. In most applications, the optical port is active for 1 to 5% of the time, corresponding to battery lifetime increasing between about 14% and 70%.

Compensatory motor control after stroke: an alternative joint strategy for object-dependent shaping of hand posture.

PubMed

Raghavan, Preeti; Santello, Marco; Gordon, Andrew M; Krakauer, John W

2010-06-01

Efficient grasping requires planned and accurate coordination of finger movements to approximate the shape of an object before contact. In healthy subjects, hand shaping is known to occur early in reach under predominantly feedforward control. In patients with hemiparesis after stroke, execution of coordinated digit motion during grasping is impaired as a result of damage to the corticospinal tract. The question addressed here is whether patients with hemiparesis are able to compensate for their execution deficit with a qualitatively different grasp strategy that still allows them to differentiate hand posture to object shape. Subjects grasped a rectangular, concave, and convex object while wearing an instrumented glove. Reach-to-grasp was divided into three phases based on wrist kinematics: reach acceleration (reach onset to peak horizontal wrist velocity), reach deceleration (peak horizontal wrist velocity to reach offset), and grasp (reach offset to lift-off). Patients showed reduced finger abduction, proximal interphalangeal joint (PIP) flexion, and metacarpophalangeal joint (MCP) extension at object grasp across all three shapes compared with controls; however, they were able to partially differentiate hand posture for the convex and concave shapes using a compensatory strategy that involved increased MCP flexion rather than the PIP flexion seen in controls. Interestingly, shape-specific hand postures did not unfold initially during reach acceleration as seen in controls, but instead evolved later during reach deceleration, which suggests increased reliance on sensory feedback. These results indicate that kinematic analysis can identify and quantify within-limb compensatory motor control strategies after stroke. From a clinical perspective, quantitative study of compensation is important to better understand the process of recovery from brain injury. From a motor control perspective, compensation can be considered a model for how joint redundancy is exploited to accomplish the task goal through redistribution of work across effectors.

Design of splints based on the NiTi alloy for the correction of joint deformities in the fingers

PubMed Central

2010-01-01

Background The proximal interphalange joint (PIP) is fundamental for the functional nature of the hand. The contracture in flexion of the PIP, secondary to traumatisms or illnesses leads to an important functional loss. The use of correcting splints is the common procedure for treating this problem. Its functioning is based on the application of a small load and a prolonged stress which can be dynamic, static progressive or static serial. It is important that the therapist has a splint available which can release a constant and sufficient force to correct the contracture in flexion. Nowadays NiTi is commonly used in bio-engineering, due to its superelastical characteristics. The experience of the authors in the design of other devices based on the NiTi alloy, makes it possible to carry out a new design in this work - the production of a finger splint for the treatment of the contracture in flexion of the PIP joint. Methods Commercial orthosis have been characterized using a universal INSTRON 5565 machine. A computational simulation of the proposed design has been conducted, reproducing its performance and using a model "ad hoc" for the NiTi material. Once the parameters have been adjusted, the design is validated using the same type of test as those carried out on commercial orthosis. Results and Discussion For commercial splint the recovering force falls to excessively low values as the angle increases. Angle curves for different lengths and thicknesses of the proposed design have been obtained, with a practically constant recovering force value over a wide range of angles that vary between 30° and 150° in every case. Then the whole treatment is possible with only one splint, and without the need of progressive replacements as the joint recovers. Conclusions A new model of splint based on NiTi alloy has been designed, simulated and tested comparing its behaviour with two of the most regularly used splints. Its uses is recommended instead of other dynamic orthosis used in orthopaedics for the PIP joint. Besides, its extremely simple design, makes its manufacture and use on the part of the specialist easier. PMID:20836874

Real-Time Visualization of Joint Cavitation

PubMed Central

Rowe, Lindsay

2015-01-01

Cracking sounds emitted from human synovial joints have been attributed historically to the sudden collapse of a cavitation bubble formed as articular surfaces are separated. Unfortunately, bubble collapse as the source of joint cracking is inconsistent with many physical phenomena that define the joint cracking phenomenon. Here we present direct evidence from real-time magnetic resonance imaging that the mechanism of joint cracking is related to cavity formation rather than bubble collapse. In this study, ten metacarpophalangeal joints were studied by inserting the finger of interest into a flexible tube tightened around a length of cable used to provide long-axis traction. Before and after traction, static 3D T1-weighted magnetic resonance images were acquired. During traction, rapid cine magnetic resonance images were obtained from the joint midline at a rate of 3.2 frames per second until the cracking event occurred. As traction forces increased, real-time cine magnetic resonance imaging demonstrated rapid cavity inception at the time of joint separation and sound production after which the resulting cavity remained visible. Our results offer direct experimental evidence that joint cracking is associated with cavity inception rather than collapse of a pre-existing bubble. These observations are consistent with tribonucleation, a known process where opposing surfaces resist separation until a critical point where they then separate rapidly creating sustained gas cavities. Observed previously in vitro, this is the first in-vivo macroscopic demonstration of tribonucleation and as such, provides a new theoretical framework to investigate health outcomes associated with joint cracking. PMID:25875374

Low-frequency periodicity in the coordination of progressive handwriting.

PubMed

Thomassen, A J; Meulenbroek, R G

1998-11-01

The paper addresses the question how the effector segments are coordinated during handwriting, in particular as a function of the left-to-right progression within words. It studies the phase relations between wrist and finger-joint rotations during a repetitive graphic task (long words consisting of letters 'e'), and it subjects the resulting continuous phase-relation plots to autocorrelation analysis. A novel phenomenon, viz. that of low-frequency (1-Hz) periodicity, is observed which presumably reflects adjustments of the coordination pattern about once per second, i.e., after every three or four letters 'e'. Moreover, word length and word position are found to affect this periodicity in a predictable manner. These results are related to those of an earlier study which used an ad-hoc method of analysing wrist-finger coordination adjustments. The paper underlines the value of phase-relation analysis for certain graphic tasks, but it also points out its limitations for this purpose.

Linear Hand Burn Contracture Release under Local Anesthesia without Tourniquet.

PubMed

Prasetyono, Theddeus O H; Koswara, Astrid F

2015-10-01

The objective of this report is to present a case of hand burn linear contracture release performed under local anesthesia. It also introduces the one-per-mil tumescent solution consisted of 0.2% lidocaine and 1:1.000.000 epinephrine as a local anesthesia formula, which has the potential of providing adequate anesthesia as well as hemostatic effect during surgery of the hand without tourniquet. The surgery was performed on a 19 year-old male patient with multiple thumb and fingers flexion linear contracture for 105 minutes without any obstacle. The patient did not complain any pain and discomfort during the procedure; while bloodless operative field was successfully achieved. At four-month follow up, the patient could fully extend his thumb, middle and ring finger, while the index was limited by 10° at the DIP joint. Overall, the patient was satisfied with the outcome.

[A rare case of tubercular tenosynovitis in hospital surgeon as a result of an occupational accident caused by puncture with an infected needle. Prevention aspects and legal-medical evaluation].

PubMed

Delli Carri, R; Piscozzi, Paola; Massimelli, M; Falcetta, R

2010-01-01

The subject was a hospital surgeon who, in the course of routine outpatient surgery with aspiration to collect right lumbar material in a patient with suspected TB infection, accidentally punctured the fifth finger of the left hand with the needle used for this procedure. This led to involvement of the fifth finger of the left hand restricted to the soft tissue with preservation of joint and bone and tenosynovial involvement of the entire extremity. To draw attention to the repercussions for insurance with resulting absence from work for 126 days and an assessment of biological impairment of 2% by the Insurance Institute (INAIL). A case report is described of rare occupational tubercular synovitis. A rare event is reported that occurred in a senior staff member with particular insurance repercussions.

Smart hands for the EVA retriever

NASA Technical Reports Server (NTRS)

Hess, Clifford W.; Li, Larry C.

1990-01-01

Dexterous, robotic hands are required for the extravehicular activity retriever (EVAR) system being developed by the NASA Johnson Space Center (JSC). These hands, as part of the EVAR system, must be able to grasp objects autonomously and securely which inadvertently separate from the Space Station. Development of the required hands was initiated in 1987. Outlined here are the hand development activities, including design considerations, progress to date, and future plans. Several types of dexterous hands that were evaluated, along with a proximity-sensing capability that was developed to initiate a reflexive, adaptive grasp, are described. The evaluations resulted in the design and fabrication of a 6-degree-of-freedom (DOF) hand that has two fingers and a thumb arranged in an anthropomorphic configuration. Finger joint force and position sensors are included in the design, as well as infrared proximity sensors which allow initiation of the grasp sequence when an object is detected within the grasp envelope.

Is 20 years of immobilization, not sufficient to render metacarpophalangeal joints completely useless?--Correction of a 20-year old post-burn palmar contracture: a case report.

PubMed

Saraiya, H

2001-03-01

This report presents a case of post-burn palmar contracture with flexion contracture of thumb of 20-year duration. The contracture was released and the raw area was covered with split thickness skin graft. Only one 'K' wire in soft tissue was needed to keep all the fingers straight and immobilized, suggestive of intermetacarpal ligamentous contracture. A static night splint was given to maintain the correction. Complete range of movement was achieved in a month with the combination of dynamic splinting and physiotherapy. It was interesting to note that even 20 years of contracted position did not render the metacarpophalangeal joints completely stiff and useless. Probable reasons are discussed.

2013 American College of Rheumatology/European League against rheumatism classification criteria for systemic sclerosis outperform the 1980 criteria: data from the Canadian Scleroderma Research Group.

PubMed

Alhajeri, Hebah; Hudson, Marie; Fritzler, Marvin; Pope, Janet; Tatibouet, Solène; Markland, Janet; Robinson, David; Jones, Niall; Khalidi, Nader; Docherty, Peter; Kaminska, Elzbieta; Masetto, Ariel; Sutton, Evelyn; Mathieu, Jean-Pierre; Ligier, Sophie; Grodzicky, Tamara; LeClercq, Sharon; Thorne, Carter; Gyger, Geneviève; Smith, Douglas; Fortin, Paul R; Larché, Maggie; Baron, Murray

2015-04-01

The goal of this study was to determine the sensitivity of the new 2013 classification criteria for systemic sclerosis (SSc; scleroderma) in an independent cohort of SSc subjects and to assess the contribution of individual items of the criteria to the overall sensitivity. SSc subjects from the Canadian Scleroderma Research Group cohort were assessed. Sensitivity was determined in several subgroups of patients. In patients without the criterion of skin thickening proximal to the metacarpophalangeal (MCP) joints, we recalculated sensitivity after removing the individual criterion. A total of 724 SSc patients were included. Most were women (86%), mean age was 55.8 years, mean disease duration was 10.9 years, and 59% had limited cutaneous SSc (lcSSc). Overall, the sensitivity of the 2013 criteria was 98.3% compared to 88.3% for the 1980 criteria. This pattern was consistent among those with lcSSc (98.8% versus 85.6%), anticentromere antibodies (98.9% versus 79.8%), disease duration ≤3 years (98.7% versus 84.7%), and no skin involvement proximal to the MCP joints (97% versus 60%). In the latter subgroup, removing Raynaud's phenomenon and sclerodactyly from the criteria reduced the sensitivity to 77% and 79%, respectively. Removing both sclerodactyly and puffy fingers reduced the sensitivity to 62%. The 2013 SSc classification criteria classify more SSc patients than the 1980 criteria. The improvement in sensitivity is most striking in those with lcSSc, especially those without skin involvement proximal to the MCP joints. The addition of Raynaud's phenomenon and puffy fingers to the 2013 criteria accounts for important gains in sensitivity. Copyright © 2015 by the American College of Rheumatology.

Mapping From an Instrumented Glove to a Robot Hand

NASA Technical Reports Server (NTRS)

Goza, Michael

2005-01-01

An algorithm has been developed to solve the problem of mapping from (1) a glove instrumented with joint-angle sensors to (2) an anthropomorphic robot hand. Such a mapping is needed to generate control signals to make the robot hand mimic the configuration of the hand of a human attempting to control the robot. The mapping problem is complicated by uncertainties in sensor locations caused by variations in sizes and shapes of hands and variations in the fit of the glove. The present mapping algorithm is robust in the face of these uncertainties, largely because it includes a calibration sub-algorithm that inherently adapts the mapping to the specific hand and glove, without need for measuring the hand and without regard for goodness of fit. The algorithm utilizes a forward-kinematics model of the glove derived from documentation provided by the manufacturer of the glove. In this case, forward-kinematics model signifies a mathematical model of the glove fingertip positions as functions of the sensor readings. More specifically, given the sensor readings, the forward-kinematics model calculates the glove fingertip positions in a Cartesian reference frame nominally attached to the palm. The algorithm also utilizes an inverse-kinematics model of the robot hand. In this case, inverse-kinematics model signifies a mathematical model of the robot finger-joint angles as functions of the robot fingertip positions. Again, more specifically, the inverse-kinematics model calculates the finger-joint commands needed to place the fingertips at specified positions in a Cartesian reference frame that is attached to the palm of the robot hand and that nominally corresponds to the Cartesian reference frame attached to the palm of the glove. Initially, because of the aforementioned uncertainties, the glove fingertip positions calculated by the forwardkinematics model in the glove Cartesian reference frame cannot be expected to match the robot fingertip positions in the robot-hand Cartesian reference frame. A calibration must be performed to make the glove and robot-hand fingertip positions correspond more precisely. The calibration procedure involves a few simple hand poses designed to provide well-defined fingertip positions. One of the poses is a fist. In each of the other poses, a finger touches the thumb. The calibration subalgorithm uses the sensor readings from these poses to modify the kinematical models to make the two sets of fingertip positions agree more closely.

The correlation between proprioception and handwriting legibility in children

PubMed Central

Hong, So Young; Jung, Nam-Hae; Kim, Kyeong Mi

2016-01-01

[Purpose] This study investigated the association between proprioception, including joint position sense and kinetic sense, and handwriting legibility in healthy children. [Subjects and Methods] Assessment of joint position sense, kinetic sense, and handwriting legibility was conducted for 19 healthy children. Joint position sense was assessed by asking the children to flex their right elbow between 30° to 110° while blindfolded. The range of elbow movement was analyzed with Compact Measuring System 10 for 3D motion Analysis. Kinetic sense was assessed using the Sensory Integration and Praxis Test. The children were directed to write 30 words from the Korean alphabet, and the legibility of their handwriting was scored for form, alignment, space, size, and shape. To analyze the data, descriptive statistics and Spearman correlation analysis were conducted using IBM SPSS Statistics 20.0. [Results] There was significant negative correlation between handwriting legibility and Kinetic sense. A significant correlation between handwriting legibility and Joint position sense was not found. [Conclusion] This study showed that a higher Kinetic sense was associated with better legibility of handwriting. Further work is needed to determine the association of handwriting legibility and speed with Joint position sense of the elbow, wrist, and fingers. PMID:27821948

Bidirectional transfer between joint and individual actions in a task of discrete force production.

PubMed

Masumoto, Junya; Inui, Nobuyuki

2017-07-01

The present study examined bidirectional learning transfer between joint and individual actions involving discrete isometric force production with the right index finger. To examine the effects of practice of joint action on performance of the individual action, participants performed a pre-test (individual condition), practice blocks (joint condition), and a post-test (individual condition) (IJI task). To examine the effects of practice of the individual action on performance during the joint action, the participants performed a pre-test (joint condition), practice blocks (individual condition), and a post-test (joint condition) (JIJ task). Whereas one participant made pressing movements with a target peak force of 10% maximum voluntary contraction (MVC) in the individual condition, two participants produced the target force of the sum of 10% MVC produced by each of them in the joint condition. In both the IJI and JIJ tasks, absolute errors and standard deviations of peak force were smaller post-test than pre-test, indicating bidirectional transfer between individual and joint conditions for force accuracy and variability. Although the negative correlation between forces produced by two participants (complementary force production) became stronger with practice blocks in the IJI task, there was no difference between the pre- and post-tests for the negative correlation in the JIJ task. In the JIJ task, the decrease in force accuracy and variability during the individual action did not facilitate complementary force production during the joint action. This indicates that practice performed by two people is essential for complementary force production in joint action.

A case of pachydermodactyly in a seventeen year old associated with repetitive minor trauma.

PubMed

Abdelrahman, W; Walsh, M Y; Smyth, A; Alderice, D

2016-08-15

A boy presented initially to a Rheumatology clinic with a three year history of asymptomatic swelling of the third to fourth proximal interphalangeal (PIP) joints bilaterally. A presumptive diagnosis of seronegative arthritis was made. Sulfasalazine was commenced without improvement and resulted in mood disturbance. Blood tests including ESR, lupus anticoagulant, rheumatoid factor and CCP antibodies were unremarkable. Hand radiographs were normal. MRI showed oedema within soft tissues around PIP joints. His care was transferred to the Rheumatology unit in our hospital and the rheumatological diagnosis was revised; sulfasalazine was stopped and skin biopsy organised. Onward referral to Dermatology was made. Examination revealed symmetrical swelling and thickening of soft tissues on PIP joints with no evidence of joint synovitis. He denied habitual behaviour but was noted to rub his fingers subconsciously. With this as a cause of repetitive minor trauma, a clinical diagnosis of pachydermodactyly was made. Skin biopsy was supportive showing a dermis with coarse collagen. Pachydermodactyly is rare. This case highlights the importance of prompt recognition to avoid invasive and excessive diagnostic procedures as well as unnecessary immunosuppression.

Pachydermodactyly and atrophia maculosa varioliformis cutis.

PubMed

Callot, V; Wechsler, J; Hovnanian, A; Revuz, J

1995-01-01

Pachydermodactyly is a rare form of superficial digital fibromatosis characterized by progressive asymptomatic thickening of the back and sides of the proximal interphalangeal joints of the fingers. Atrophia maculosa varioliformis cutis is an acquired dermal atrophy, localized on the cheeks. Only a few cases of each pathology have been published. We find it interesting to report the case of a patient with both conditions as these two connective-tissue diseases are very rare. The association is probably fortuitous.

Measurement of oxidative metabolism of the working human muscles by near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Yücetaş, Akin; Şayli, Ömer; Karahan, Mustafa; Akin, Ata

2006-02-01

Monitoring the oxygenation of skeletal muscle tissues during rest to work transient provides valuable information about the performance of a particular tissue in adapting to aerobic glycolysis. In this paper we analyze the temporal relation of O II consumption with deoxy-hemoglobin (Hb) signals measured by functional Near Infrared Spectroscopy (fNIRS) technique during moderate isotonic forearm finger joint flexion exercise under ischemic conditions and model it with a mono exponential equation with delay. The time constants of fitting equation are questioned under two different work loads and among subjects differing in gender. Ten (6 men and 4 women) subjects performed isotonic forearm finger joint flexion exercise with two different loads. It is shown that under the same load, men and women subjects generate similar time constants and time delays. However, apparent change in time constants and time delays were observed when exercise was performed under different loads. When t-test is applied to compare the outputs for time constants between 0.41202 Watts and 0.90252 Watts, P value of 9.3445x10 -4 < 0.05 is observed which implies that the differences between the time constants are statistically significant. When the same procedure is applied for the time delay comparison, P value of 0.027<0.05 is observed which implies that also the differences between the time delays are statistically significant.

[Results of flexor tendon sutures of the fingers with 2-strand (40 tendons) and 4-strand (64 tendons) core sutures].

PubMed

Winkel, R; Kalbhenn, O; Hoffmann, R

2012-06-01

This retrospective examination compares the results of finger flexor tendon sutures with 2 strands and 4 strands. It was checked, whether and how 2 more strands influenced the rupture rate, the movement of the finger and the contentment of the patients. From 1996 to 2000 for the core suture of the flexor tendon of fingers we used 2 strands. 35 patients with 40 tendon sutures of 73 patients were examined. From 2001 to 2005 we used for the core suture 2 loop threads. 53 patients with 64 tendon sutures from a total of 111 patients were examined. At least 12 months had passed between operation and the examination. The rupture rate and the range of movement of each finger joint and the total mobility of the affected fingers were evaluated. Each case was compared to the uninjured opposite hand. The functional result was judged according to the score of Buck-Gramcko. The patient's contentment was recorded by the DASH (disability of arm, shoulder and hand) score. Effects of gender, age, accompanying injuries, zone of the injury and their influence on the results were analysed. The Buck-Gramcko score showed in the 2-strand group a distribution from summarised 70% "excellent" and "good" and 30% "fair" and "poor". In the 4-strand-group the relation was 93.7% "excellent" and "good", 6.3% "fair", one "poor". In the 2-strand group 2/40 (5%) of the tendon sutures ruptured, in the 4-strand group 1/64 (1.6%) ruptured. The average DASH value in the 2-strands-group was 16.6/100, in the 4-strands-group 18.1/100 when 0 is the best possible result and 100 the worst. The patient judgement in the 2-strand group was summarised to 70% for "excellent" and "good" and 30% "fair" and "poor". In the 4-strand group the patient's judgment was summarised in 75% "excellent" and "good" and in 25% "fair". The results of flexor tendon sutures with 4-strand core sutures have been superior to the results with 2-strand core suture according to range of motion of the fingers (P <0.005). © Georg Thieme Verlag KG Stuttgart · New York.

The prevalence of the sesamoid bones of the hand: a systematic review and meta-analysis.

PubMed

Yammine, Kaissar

2014-11-01

The literature contains various estimates of the prevalence and distribution of the sesamoid bones in the hands. The aims of this systematic review are to provide a better estimate of the frequency of hand sesamoids and its association with variables such as ancestry, gender, and side. Nineteen studies met the inclusion criteria. The pooled rates of the sensitive meta-analyses from large-sample studies in adults showed: (a) true overall rates of 99.9% for the metacarpophalangeal (MCP) joint of the thumb (MCP-I), 53% for the interphalangeal joint (IP-I), 43.4% for the MCP of the index (MCP-II), 1.47% for the MCP of the medius finger (MCP-III), 0.6% for the MCP of the ring finger (MCP-IV), and 67.7% for the MCP of the auricular finger (MCP-V); (b) true radiological rates of 99.9% for the radial thumb sesamoid, 99.6% for the ulnar thumb sesamoid, 47.8% for IP-I, 40% for MCP-II, 1.3% for MCP-III, 0.8% for MCP-VI, and 62.8% for MCP-V. Black, Middle Eastern, and European ancestries conferred significantly higher sesamoid frequencies at IP-I, MCP-II, and MCP-V, respectively. There was a significant association with female gender at MCP-II, MCP-IV, and MCP-V, with ORs of 1.53, 4, and 1.3, respectively, and a nonsignificant "female" trend for the other locations. There was no significant association with hand side. The pooled rates of hand sesamoids in children aged 10-17 years were 92.7, 42.2, 33.8, 0.5, 0.3, and 36.5% for MCP-I, IP-I, MCP-II, MCP-III, MCP-IV, and MCP-V, respectively. The findings of this evidence-based anatomical review provide quantitative evidence that the incidence of sesamoid bones in human hands depends on genetic rather than functional factors. © 2014 Wiley Periodicals, Inc.

Ultrasonographic evaluation of displaced neurovascular bundle in Dupuytren disease.

PubMed

Uehara, Kosuke; Miura, Toshiki; Morizaki, Yutaka; Miyamoto, Hideaki; Ohe, Takashi; Tanaka, Sakae

2013-01-01

Neurovascular injury is a serious complication after surgery for Dupuytren disease. The purpose of this study was to evaluate the relationship between the cord and the neurovascular bundle ultrasonographically. We included 22 healthy volunteers and 14 Dupuytren disease patients (25 fingers) in this study. We evaluated the cord and the digital artery with high-resolution ultrasound. We first investigated the effect of the angle of metacarpophalangeal joint on the position of the radial and ulnar digital arteries in volunteers without evidence of Dupuytren disease. We compared 3 parameters of the radial and ulnar digital arteries, including differences in depth, differences in lateral shift, and the shape of the cross-section of the artery, between volunteers and patients with Dupuytren disease. None of these parameters changed with flexion of the metacarpophalangeal joint of 0°, 30°, and 60°. Digital arteries and cords could be identified ultrasonographically in all patients, and we confirmed ultrasonographic findings by operative findings in 13 fingers. We classified the fingers into 3 subgroups based on the ultrasonographic findings: type A (n = 13), in which the cord was above the artery; type B (n = 5), in which the cord was below the artery; and type C (n = 7), in which the cord was located between the radial and ulnar digital arteries. Types A, B, and C corresponded to natatory cord/abductor digiti minimi cord, spiral cord, and central cord, respectively. Comparisons among volunteers and patient subgroups showed that the difference in depth in type B patients was significantly larger than that of the other groups. When we set the cutoff point of the difference in depth to 3 mm, sensitivity and specificity to detect the spiral cord were 80% and 76%, respectively. The relationship between the neurovascular bundle and the type of Dupuytren disease cord can be evaluated by high-resolution ultrasound. Diagnostic III. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Neuromorphic meets neuromechanics, part I: the methodology and implementation

NASA Astrophysics Data System (ADS)

Niu, Chuanxin M.; Jalaleddini, Kian; Sohn, Won Joon; Rocamora, John; Sanger, Terence D.; Valero-Cuevas, Francisco J.

2017-04-01

Objective: One goal of neuromorphic engineering is to create ‘realistic’ robotic systems that interact with the physical world by adopting neuromechanical principles from biology. Critical to this is the methodology to implement the spinal circuitry responsible for the behavior of afferented muscles. At its core, muscle afferentation is the closed-loop behavior arising from the interactions among populations of muscle spindle afferents, alpha and gamma motoneurons, and muscle fibers to enable useful behaviors. Approach. We used programmable very- large-scale-circuit (VLSI) hardware to implement simple models of spiking neurons, skeletal muscles, muscle spindle proprioceptors, alpha-motoneuron recruitment, gamma motoneuron control of spindle sensitivity, and the monosynaptic circuitry connecting them. This multi-scale system of populations of spiking neurons emulated the physiological properties of a pair of antagonistic afferented mammalian muscles (each simulated by 1024 alpha- and gamma-motoneurones) acting on a joint via long tendons. Main results. This integrated system was able to maintain a joint angle, and reproduced stretch reflex responses even when driving the nonlinear biomechanics of an actual cadaveric finger. Moreover, this system allowed us to explore numerous values and combinations of gamma-static and gamma-dynamic gains when driving a robotic finger, some of which replicated some human pathological conditions. Lastly, we explored the behavioral consequences of adopting three alternative models of isometric muscle force production. We found that the dynamic responses to rate-coded spike trains produce force ramps that can be very sensitive to tendon elasticity, especially at high force output. Significance. Our methodology produced, to our knowledge, the first example of an autonomous, multi-scale, neuromorphic, neuromechanical system capable of creating realistic reflex behavior in cadaveric fingers. This research platform allows us to explore the mechanisms behind healthy and pathological sensorimotor function in the physical world by building them from first principles, and it is a precursor to neuromorphic robotic systems.

Pain is Associated to Clinical, Psychological, Physical, and Neurophysiological Variables in Women With Carpal Tunnel Syndrome.

PubMed

Fernández-Muñoz, Juan J; Palacios-Ceña, María; Cigarán-Méndez, Margarita; Ortega-Santiago, Ricardo; de-la-Llave-Rincón, Ana I; Salom-Moreno, Jaime; Fernández-de-las-Peñas, César

2016-02-01

To investigate potential relationships of clinical (age, function, side of pain, years with pain), physical (cervical range of motion, pinch grip force), psychological (depression), and neurophysiological (pressure and thermal pain thresholds) outcomes and hand pain intensity in carpal tunnel syndrome (CTS). Two hundred and forty-four (n=224) women with CTS were recruited. Demographic data, duration of the symptoms, function and severity of the disease, pain intensity, depression, cervical range of motion, pinch tip grip force, heat/cold pain thresholds (HPT/CPT), and pressure pain thresholds (PPT) were collected. Correlation and regression analysis were performed to determine the association among those variables and to determine the proportions of explained variance in hand pain intensity. Significant negative correlations existed between the intensity of pain and PPTs over the radial nerve, C5/C6 zygapophyseal joint, carpal tunnel and tibialis anterior muscle, HPT over the carpal tunnel, cervical extension and lateral-flexion, and thumb-middle, fourth, and little finger pinch tip forces. Significant positive correlations between the intensity of hand pain with function and depression were also observed. Stepwise regression analyses revealed that function, thumb-middle finger pinch, thumb-little finger pinch, depression, PPT radial nerve, PPT carpal tunnel, and HPT carpal tunnel were significant predictors of intensity of hand pain (R²=0.364; R² adjusted=0.343; F=16.87; P<0.001). This study showed that 36.5% of the variance of pain intensity was associated to clinical (function), neurophysiological (localized PPT and HPT), psychological (depression), and physical (finger pinch tip force) outcomes in women with chronic CTS.

Electromyography of wrist and finger flexor muscles in olive baboons (Papio anubis).

PubMed

Patel, Biren A; Larson, Susan G; Stern, Jack T

2012-01-01

Some non-human primates use digitigrade hand postures when walking slowly on the ground. As a component of an extended limb, a digitigrade posture can help minimize wrist joint moments thereby requiring little force production directly from wrist flexors (and/or from the assistance of finger flexors) to maintain limb posture. As a consequence, less active muscle volume would be required from these anti-gravity muscles and overall metabolic costs associated with locomotion could be reduced. To investigate whether the use of digitigrade hand postures during walking in primates entails minimal use of anti-gravity muscles, this study examined electromyography (EMG) patterns in both the wrist and finger flexor muscles in facultatively digitigrade olive baboons (Papio anubis) across a range of speeds. The results demonstrate that baboons can adopt a digitigrade hand posture when standing and moving at slow speeds without requiring substantial EMG activity from distal anti-gravity muscles. Higher speed locomotion, however, entails increasing EMG activity and is accompanied by a dynamic shift to a more palmigrade-like limb posture. Thus, the ability to adopt a digitigrade hand posture by monkeys is an adaptation for ground living, but it was never co-opted for fast locomotion. Rather, digitigrady in primates appears to be related to energetic efficiency for walking long distances.

Comparison of Transverse Intraosseous Loop Technique and Pull Out Suture for Reinsertion of the Flexor Digitorum Profundus tendon. A Retrospective Study.

PubMed

Rigó, István Zoltán; Røkkum, Magne

2013-12-01

We compared the results of two methods for reinsertion of flexor digitorum profundus tendons retrospectively. In 35 fingers of 29 patients pull-out suture and in 13 fingers of 11 patients transverse intraosseous loop technique was performed with a mean follow-up of 8 and 6 months, respectively. Eleven and nine fingers achieved "excellent" or "good" function according to Strickland and Glogovac at 8 weeks; 20 and ten at the last control in the pull-out and transverse intraosseous loop groups, respectively. The difference at 8 weeks was statistically significant in favour of the transverse intraosseous loop group. Ten patients underwent 12 complications in the pull-out group (four superficial infections; one rerupture, one PIP and one DIP joint contracture, one adhesion, two granulomas, one nail deformity and one carpal tunnel syndrome) and four of them were reoperated (one carpal tunnel release, one teno-arthrolysis and two resections of granuloma). There was no complication and no reoperation in the transverse intraosseous loop group, the difference being statistically significant for the former. In our study the transverse intraosseous loop technique seemed to be a safe alternative with possibly better functional results compared to the pull-out suture.

Analysis of Potential Glove-Induced Hand Injury Metrics During Typical Neutral Buoyancy Training Operations

NASA Technical Reports Server (NTRS)

McFarland, Shane

2016-01-01

Injuries to the hands are common among astronauts who train for extravehicular activity. When the gloves are pressurized, they restrict movement and create pressure points during tasks, sometimes resulting in pain, muscle fatigue, abrasions, and occasionally more severe injuries such as onycholysis. A brief review of NASA's Lifetime Surveillance of Astronaut Health's injury database reveals that 76 percent of astronaut hand and arm injuries from training between 1993 and 2010 occurred either to the fingernail, finger crotch, metacarpophalangeal joint, or fingertip. The purpose of this study was to assess the potential of using small sensors to measure forces acting on the fingers and hand within pressurized gloves and other variables such as skin temperature, humidity, and fingernail strain of a NASA crewmember during typical NBL (Neutral Buoyancy Laboratory) training activity. During the 5-hour exercise, the crewmember seemed to exhibit very large forces on some fingers, resulting in higher strain than seen in previous glove-box testing. In addition, vital information was collected on the glove cavity environment with respect to temperature and humidity. All of this information gathered during testing will be carried forward into future testing, potentially in glove-box- or 1G- (1 gravitational force) or NBL-suited environments, to better characterize and understand the possible causes of hand injury amongst NASA crew.

Combining variational and model-based techniques to register PET and MR images in hand osteoarthritis

NASA Astrophysics Data System (ADS)

Magee, Derek; Tanner, Steven F.; Waller, Michael; Tan, Ai Lyn; McGonagle, Dennis; Jeavons, Alan P.

2010-08-01

Co-registration of clinical images acquired using different imaging modalities and equipment is finding increasing use in patient studies. Here we present a method for registering high-resolution positron emission tomography (PET) data of the hand acquired using high-density avalanche chambers with magnetic resonance (MR) images of the finger obtained using a 'microscopy coil'. This allows the identification of the anatomical location of the PET radiotracer and thereby locates areas of active bone metabolism/'turnover'. Image fusion involving data acquired from the hand is demanding because rigid-body transformations cannot be employed to accurately register the images. The non-rigid registration technique that has been implemented in this study uses a variational approach to maximize the mutual information between images acquired using these different imaging modalities. A piecewise model of the fingers is employed to ensure that the methodology is robust and that it generates an accurate registration. Evaluation of the accuracy of the technique is tested using both synthetic data and PET and MR images acquired from patients with osteoarthritis. The method outperforms some established non-rigid registration techniques and results in a mean registration error that is less than approximately 1.5 mm in the vicinity of the finger joints.

Haptic stabilization of posture: changes in arm proprioception and cutaneous feedback for different arm orientations

NASA Technical Reports Server (NTRS)

Rabin, E.; Bortolami, S. B.; DiZio, P.; Lackner, J. R.

1999-01-01

Postural sway during quiet stance is attenuated by actively maintained contact of the index finger with a stationary surface, even if the level of applied force (<1 N) cannot provide mechanical stabilization. In this situation, changes in force level at the fingertip lead changes in center of foot pressure by approximately 250 ms. These and related findings indicate that stimulation of the fingertip combined with proprioceptive information about the hand and arm can serve as an active sensor of body position relative to the point of contact. A geometric analysis of the relationship between hand and torso displacement during body sway led to the prediction that arm and hand proprioceptive and finger somatosensory information about body sway would be maximized with finger contact in the plane of body sway. Therefore, the most postural stabilization should be possible with such contact. To test this analysis, subjects touched a laterally versus anteriorly placed surface while in each of two stances: the heel-to-toe tandem Romberg stance that reduces medial-lateral stability and the heel-to-heel, toes-outward, knees-bent, "duck stance" that reduces fore-aft stability. Postural sway was always least with finger contact in the unstable plane: for the tandem stance, lateral fingertip contact was significantly more effective than frontal contact, and, for the duck stance, frontal contact was more effective than lateral fingertip contact. Force changes at the fingertip led changes in center of pressure of the feet by approximately 250 ms for both fingertip contact locations for both test stances. These results support the geometric analysis, which showed that 1) arm joint angles change by the largest amount when fingertip contact is maintained in the plane of greatest sway, and 2) the somatosensory cues at the fingertip provide both direction and amplitude information about sway when the finger is contacting a surface in the unstable plane.

Haptic stabilization of posture: changes in arm proprioception and cutaneous feedback for different arm orientations.

PubMed

Rabin, E; Bortolami, S B; DiZio, P; Lackner, J R

1999-12-01

Postural sway during quiet stance is attenuated by actively maintained contact of the index finger with a stationary surface, even if the level of applied force (<1 N) cannot provide mechanical stabilization. In this situation, changes in force level at the fingertip lead changes in center of foot pressure by approximately 250 ms. These and related findings indicate that stimulation of the fingertip combined with proprioceptive information about the hand and arm can serve as an active sensor of body position relative to the point of contact. A geometric analysis of the relationship between hand and torso displacement during body sway led to the prediction that arm and hand proprioceptive and finger somatosensory information about body sway would be maximized with finger contact in the plane of body sway. Therefore, the most postural stabilization should be possible with such contact. To test this analysis, subjects touched a laterally versus anteriorly placed surface while in each of two stances: the heel-to-toe tandem Romberg stance that reduces medial-lateral stability and the heel-to-heel, toes-outward, knees-bent, "duck stance" that reduces fore-aft stability. Postural sway was always least with finger contact in the unstable plane: for the tandem stance, lateral fingertip contact was significantly more effective than frontal contact, and, for the duck stance, frontal contact was more effective than lateral fingertip contact. Force changes at the fingertip led changes in center of pressure of the feet by approximately 250 ms for both fingertip contact locations for both test stances. These results support the geometric analysis, which showed that 1) arm joint angles change by the largest amount when fingertip contact is maintained in the plane of greatest sway, and 2) the somatosensory cues at the fingertip provide both direction and amplitude information about sway when the finger is contacting a surface in the unstable plane.

Effectiveness of a fine motor skills rehabilitation program on upper limb disability, manual dexterity, pinch strength, range of fingers motion, performance in activities of daily living, functional independency, and general self-efficacy in hand osteoarthritis: A randomized clinical trial.

PubMed

Pérez-Mármol, Jose Manuel; García-Ríos, Ma Carmen; Ortega-Valdivieso, María Azucena; Cano-Deltell, Enrique Elías; Peralta-Ramírez, María Isabel; Ickmans, Kelly; Aguilar-Ferrándiz, María Encarnación

A randomized clinical trial. Rehabilitation treatments for improving fine motor skills (FMS) in hand osteoarthritis (HOA) have not been well explored yet. To assess the effectiveness of a rehabilitation program on upper limb disability, independence of activities of daily living (ADLs), fine motor abilities, functional independency, and general self-efficacy in older adults with HOA. About 45 adults (74-86 years) with HOA were assigned to an experimental group for completing an FMS intervention or a control group receiving conventional occupational therapy. Both interventions were performed 3 times/wk, 45 minutes each session, during 8 weeks. Upper limb disability, performance in ADLs, pinch strength, manual dexterity, range of fingers motion, functional independency, and general self-efficacy were assessed at baseline, immediately after treatment, and after 2 months of follow-up. FMS group showed significant improvements with a small effect size on manual dexterity (P ≤ .034; d ≥ 0.48) and a moderate-high effect on range of index (P ≤ .018; d ≥ 0.58) and thumb (P ≤ .027; d ≥ 0.39) motion. The control group showed a significant worse range of motion over time in some joints at the index (P ≤ .037; d ≥ 0.36) finger and thumb (P ≤ .017; d ≥ 0.55). A rehabilitation intervention for FMS may improve manual dexterity and range of fingers motion in HOA, but its effects on upper limb disability, performance in ADLs, pinch strength, functionality, and self-efficacy remain uncertain. Specific interventions of the hand are needed to prevent a worsening in range of finger motion. 1b. Copyright © 2016 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Adapting human-machine interfaces to user performance.

PubMed

Danziger, Zachary; Fishbach, Alon; Mussa-Ivaldi, Ferdinando A

2008-01-01

The goal of this study was to create and examine machine learning algorithms that adapt in a controlled and cadenced way to foster a harmonious learning environment between the user of a human-machine interface and the controlled device. In this experiment, subjects' high-dimensional finger motions remotely controlled the joint angles of a simulated planar 2-link arm, which was used to hit targets on a computer screen. Subjects were required to move the cursor at the endpoint of the simulated arm.

Assessment and prediction of inter-joint upper limb movement correlations based on kinematic analysis and statistical regression

NASA Astrophysics Data System (ADS)

Toth-Tascau, Mirela; Balanean, Flavia; Krepelka, Mircea

2013-10-01

Musculoskeletal impairment of the upper limb can cause difficulties in performing basic daily activities. Three dimensional motion analyses can provide valuable data of arm movement in order to precisely determine arm movement and inter-joint coordination. The purpose of this study was to develop a method to evaluate the degree of impairment based on the influence of shoulder movements in the amplitude of elbow flexion and extension based on the assumption that a lack of motion of the elbow joint will be compensated by an increased shoulder activity. In order to develop and validate a statistical model, one healthy young volunteer has been involved in the study. The activity of choice simulated blowing the nose, starting from a slight flexion of the elbow and raising the hand until the middle finger touches the tip of the nose and return to the start position. Inter-joint coordination between the elbow and shoulder movements showed significant correlation. Statistical regression was used to fit an equation model describing the influence of shoulder movements on the elbow mobility. The study provides a brief description of the kinematic analysis protocol and statistical models that may be useful in describing the relation between inter-joint movements of daily activities.

Space suit glove design with advanced metacarpal phalangeal joints and robotic hand evaluation.

PubMed

Southern, Theodore; Roberts, Dustyn P; Moiseev, Nikolay; Ross, Amy; Kim, Joo H

2013-06-01

One area of space suits that is ripe for innovation is the glove. Existing models allow for some fine motor control, but the power grip--the act of grasping a bar--is cumbersome due to high torque requirements at the knuckle or metacarpal phalangeal joint (MCP). This area in particular is also a major source of complaints of pain and injury as reported by astronauts. This paper explores a novel fabrication and patterning technique that allows for more freedom of movement and less pain at this crucial joint in the manned space suit glove. The improvements are evaluated through unmanned testing, manned testing while depressurized in a vacuum glove box, and pressurized testing with a robotic hand. MCP joint flex score improved from 6 to 6.75 (out of 10) in the final glove relative to the baseline glove, and torque required for flexion decreased an average of 17% across all fingers. Qualitative assessments during unpressurized and depressurized manned testing also indicated the final glove was more comfortable than the baseline glove. The quantitative results from both human subject questionnaires and robotic torque evaluation suggest that the final iteration of the glove design enables flexion at the MCP joint with less torque and more comfort than the baseline glove.

Infrared laser transillumination CT imaging system using parallel fiber arrays and optical switches for finger joint imaging

NASA Astrophysics Data System (ADS)

Sasaki, Yoshiaki; Emori, Ryota; Inage, Hiroki; Goto, Masaki; Takahashi, Ryo; Yuasa, Tetsuya; Taniguchi, Hiroshi; Devaraj, Balasigamani; Akatsuka, Takao

2004-05-01

The heterodyne detection technique, on which the coherent detection imaging (CDI) method founds, can discriminate and select very weak, highly directional forward scattered, and coherence retaining photons that emerge from scattering media in spite of their complex and highly scattering nature. That property enables us to reconstruct tomographic images using the same reconstruction technique as that of X-Ray CT, i.e., the filtered backprojection method. Our group had so far developed a transillumination laser CT imaging method based on the CDI method in the visible and near-infrared regions and reconstruction from projections, and reported a variety of tomographic images both in vitro and in vivo of biological objects to demonstrate the effectiveness to biomedical use. Since the previous system was not optimized, it took several hours to obtain a single image. For a practical use, we developed a prototype CDI-based imaging system using parallel fiber array and optical switches to reduce the measurement time significantly. Here, we describe a prototype transillumination laser CT imaging system using fiber-optic based on optical heterodyne detection for early diagnosis of rheumatoid arthritis (RA), by demonstrating the tomographic imaging of acrylic phantom as well as the fundamental imaging properties. We expect that further refinements of the fiber-optic-based laser CT imaging system could lead to a novel and practical diagnostic tool for rheumatoid arthritis and other joint- and bone-related diseases in human finger.

Sensory integration of a light touch reference in human standing balance.

PubMed

Assländer, Lorenz; Smith, Craig P; Reynolds, Raymond F

2018-01-01

In upright stance, light touch of a space-stationary touch reference reduces spontaneous sway. Moving the reference evokes sway responses which exhibit non-linear behavior that has been attributed to sensory reweighting. Reweighting refers to a change in the relative contribution of sensory cues signaling body sway in space and light touch cues signaling finger position with respect to the body. Here we test the hypothesis that the sensory fusion process involves a transformation of light touch signals into the same reference frame as other sensory inputs encoding body sway in space, or vice versa. Eight subjects lightly gripped a robotic manipulandum which moved in a circular arc around the ankle joint. A pseudo-randomized motion sequence with broad spectral characteristics was applied at three amplitudes. The stimulus was presented at two different heights and therefore different radial distances, which were matched in terms of angular motion. However, the higher stimulus evoked a significantly larger sway response, indicating that the response was not matched to stimulus angular motion. Instead, the body sway response was strongly related to the horizontal translation of the manipulandum. The results suggest that light touch is integrated as the horizontal distance between body COM and the finger. The data were well explained by a model with one feedback loop minimizing changes in horizontal COM-finger distance. The model further includes a second feedback loop estimating the horizontal finger motion and correcting the first loop when the touch reference is moving. The second loop includes the predicted transformation of sensory signals into the same reference frame and a non-linear threshold element that reproduces the non-linear sway responses, thus providing a mechanism that can explain reweighting.

Interpersonal synergies: static prehension tasks performed by two actors.

PubMed

Solnik, Stanislaw; Reschechtko, Sasha; Wu, Yen-Hsun; Zatsiorsky, Vladimir M; Latash, Mark L

2016-08-01

We investigated multidigit synergies stabilizing components of the resultant force vector during joint performance of a static prehension task by two persons as compared to similar tasks performed by a single person using both hands. Subjects transferred the instrumented handle from the right hand to the left hand (one-person condition) or passed that handle to another person (two-person condition) while keeping the handle's position and orientation stationary. Only three digits were involved per hand, the thumb, the index finger, and the middle finger; the forces and moments produced by the digits were measured by six-component sensors. We estimated the performance-stabilizing synergies within the uncontrolled manifold framework by quantifying the intertrial variance structure of digit forces and moments. The analysis was performed at three levels: between hands, between virtual finger and virtual thumb (imagined digits producing the same mechanical variables as the corresponding actual digits combined) produced by the two hands (in both interpersonal and intrapersonal conditions), and between the thumb and virtual finger for one hand only. Additionally, we performed correlation and phase synchronization analyses of resultant tangential forces and internal normal forces. Overall, the one-person conditions were characterized by higher amount of intertrial variance that did not affect resultant normal force components, higher internal components of normal forces, and stronger synchronization of the normal forces generated by the hands. Our observations suggest that in two-person tasks, when participants try to achieve a common mechanical outcome, the performance-stabilizing synergies depend on non-visual information exchange, possibly via the haptic and proprioceptive systems. Therefore, synergies quantified in tasks using visual feedback only may not be generalizable to more natural tasks.

Long-term functional, subjective and psychological results after single digit replantation.

PubMed

Chen, Jing; Zhang, Ai Xian; Chen, Qing Zhong; Mu, Shuai; Tan, Jun

2018-03-01

The aim of this study was to analyse the long-term functional, subjective, and psychological results after single-digit replantation. Thirty cases of digital replantation (14 thumbs, 12 index fingers, 2 middle fingers, 1 ring finger, and 1 little finger) in 30 patients (7 females and 23 males) with a mean age of 44.2 years (20-65 years) were evaluated at the end of a mean follow-up time of 36 months (19-50 months). The active range of motion of joints, grip and pinch strength, cutaneous sensibility, upper-extremity functioning, and subjective satisfaction were determined using the Disability of Arm, Shoulder, and Hand (DASH) questionnaire and the Michigan Hand Outcomes questionnaire (MHQ). Psychological sequelae, including depression, anxiety, and posttraumatic stress disorder (PTSD), were assessed. A correlation analysis among variables was also performed. The mean score for the DASH questionnaire was 6.6 (range: 0-39.2). The symptom of cold intolerance occurred in 53% of the patients. Two patients were diagnosed with depression, and only one patient exhibited PTSD. The DASH score had a good statistical correlation with total grip strength, pinch grip strength, and static two-point discrimination (S-2PD) (P < 0.05). Several aspects of the MHQ were also statistically relevant to some or all of the three objective results. Furthermore, the grip strength showed significant correlation with DASH and most aspects of the MHQ in multivariate logistic regression analysis (P < 0.05). Total grip strength is the most important factor positively related to subjective outcomes. The incidence rates of psychological symptoms after digit replantation are very low at long-term follow-up. Level IV, therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

Sensory integration of a light touch reference in human standing balance

PubMed Central

Smith, Craig P.; Reynolds, Raymond F.

2018-01-01

In upright stance, light touch of a space-stationary touch reference reduces spontaneous sway. Moving the reference evokes sway responses which exhibit non-linear behavior that has been attributed to sensory reweighting. Reweighting refers to a change in the relative contribution of sensory cues signaling body sway in space and light touch cues signaling finger position with respect to the body. Here we test the hypothesis that the sensory fusion process involves a transformation of light touch signals into the same reference frame as other sensory inputs encoding body sway in space, or vice versa. Eight subjects lightly gripped a robotic manipulandum which moved in a circular arc around the ankle joint. A pseudo-randomized motion sequence with broad spectral characteristics was applied at three amplitudes. The stimulus was presented at two different heights and therefore different radial distances, which were matched in terms of angular motion. However, the higher stimulus evoked a significantly larger sway response, indicating that the response was not matched to stimulus angular motion. Instead, the body sway response was strongly related to the horizontal translation of the manipulandum. The results suggest that light touch is integrated as the horizontal distance between body COM and the finger. The data were well explained by a model with one feedback loop minimizing changes in horizontal COM-finger distance. The model further includes a second feedback loop estimating the horizontal finger motion and correcting the first loop when the touch reference is moving. The second loop includes the predicted transformation of sensory signals into the same reference frame and a non-linear threshold element that reproduces the non-linear sway responses, thus providing a mechanism that can explain reweighting. PMID:29874252

State-based decoding of hand and finger kinematics using neuronal ensemble and LFP activity during dexterous reach-to-grasp movements

PubMed Central

Mollazadeh, Mohsen; Davidson, Adam G.; Schieber, Marc H.; Thakor, Nitish V.

2013-01-01

The performance of brain-machine interfaces (BMIs) that continuously control upper limb neuroprostheses may benefit from distinguishing periods of posture and movement so as to prevent inappropriate movement of the prosthesis. Few studies, however, have investigated how decoding behavioral states and detecting the transitions between posture and movement could be used autonomously to trigger a kinematic decoder. We recorded simultaneous neuronal ensemble and local field potential (LFP) activity from microelectrode arrays in primary motor cortex (M1) and dorsal (PMd) and ventral (PMv) premotor areas of two male rhesus monkeys performing a center-out reach-and-grasp task, while upper limb kinematics were tracked with a motion capture system with markers on the dorsal aspect of the forearm, hand, and fingers. A state decoder was trained to distinguish four behavioral states (baseline, reaction, movement, hold), while a kinematic decoder was trained to continuously decode hand end point position and 18 joint angles of the wrist and fingers. LFP amplitude most accurately predicted transition into the reaction (62%) and movement (73%) states, while spikes most accurately decoded arm, hand, and finger kinematics during movement. Using an LFP-based state decoder to trigger a spike-based kinematic decoder [r = 0.72, root mean squared error (RMSE) = 0.15] significantly improved decoding of reach-to-grasp movements from baseline to final hold, compared with either a spike-based state decoder combined with a spike-based kinematic decoder (r = 0.70, RMSE = 0.17) or a spike-based kinematic decoder alone (r = 0.67, RMSE = 0.17). Combining LFP-based state decoding with spike-based kinematic decoding may be a valuable step toward the realization of BMI control of a multifingered neuroprosthesis performing dexterous manipulation. PMID:23536714

Intelligent, self-contained robotic hand

DOEpatents

Krutik, Vitaliy; Doo, Burt; Townsend, William T.; Hauptman, Traveler; Crowell, Adam; Zenowich, Brian; Lawson, John

2007-01-30

A robotic device has a base and at least one finger having at least two links that are connected in series on rotary joints with at least two degrees of freedom. A brushless motor and an associated controller are located at each joint to produce a rotational movement of a link. Wires for electrical power and communication serially connect the controllers in a distributed control network. A network operating controller coordinates the operation of the network, including power distribution. At least one, but more typically two to five, wires interconnect all the controllers through one or more joints. Motor sensors and external world sensors monitor operating parameters of the robotic hand. The electrical signal output of the sensors can be input anywhere on the distributed control network. V-grooves on the robotic hand locate objects precisely and assist in gripping. The hand is sealed, immersible and has electrical connections through the rotary joints for anodizing in a single dunk without masking. In various forms, this intelligent, self-contained, dexterous hand, or combinations of such hands, can perform a wide variety of object gripping and manipulating tasks, as well as locomotion and combinations of locomotion and gripping.

Process for anodizing a robotic device

DOEpatents

Townsend, William T [Weston, MA

2011-11-08

A robotic device has a base and at least one finger having at least two links that are connected in series on rotary joints with at least two degrees of freedom. A brushless motor and an associated controller are located at each joint to produce a rotational movement of a link. Wires for electrical power and communication serially connect the controllers in a distributed control network. A network operating controller coordinates the operation of the network, including power distribution. At least one, but more typically two to five, wires interconnect all the controllers through one or more joints. Motor sensors and external world sensors monitor operating parameters of the robotic hand. The electrical signal output of the sensors can be input anywhere on the distributed control network. V-grooves on the robotic hand locate objects precisely and assist in gripping. The hand is sealed, immersible and has electrical connections through the rotary joints for anodizing in a single dunk without masking. In various forms, this intelligent, self-contained, dexterous hand, or combinations of such hands, can perform a wide variety of object gripping and manipulating tasks, as well as locomotion and combinations of locomotion and gripping.

Predictive grade of ultrasound synovitis for diagnosing rheumatoid arthritis in clinical practice and the possible difference between patients with and without seropositivity.

PubMed

Minowa, Kentaro; Ogasawara, Michihiro; Murayama, Go; Gorai, Misa; Yamada, Yusuke; Nemoto, Takuya; Matsuki, Yuko; Sugisaki, Nagachika; Ando, Seiichiro; Kon, Takayuki; Tada, Kurisu; Matsushita, Masakazu; Yamaji, Ken; Tamura, Naoto; Takasaki, Yoshinari

2016-01-01

To determine the degree of contribution and the contributing factors of ultrasound in the diagnosis of rheumatoid arthritis (RA) in daily clinical practice and the predictive differences depending on seropositivity. We included 122 patients who presented with the main complaint of finger and/or wrist joint pain but for whom no definite diagnosis was reached or treatment strategy was provided. Ultrasound was performed on at least 22 joints (both wrist joints, proximal interphalangeal joint, and metacarpophalangeal joints), and patients were followed for ≥6 months. Factors contributing to RA diagnosis were determined and compared between seropositive and seronegative RA patients. RA was diagnosed in 52 of 122 patients, in whom the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria (odds ratio [OR] = 4.74, P = 0.01) and gray scale (GS) grade of 3 (OR = 3.64, P = 0.04) for ≥ 1 joint were the contributing factors. In seropositive RA, the ACR/EULAR criteria (OR = 15.53, P < 0.001) and power Doppler (PD) ≥ 2 for ≥ 1 joint (OR = 10.48, P = 0.0048) were the contributing factors. In seronegative RA, PD ≥ 1 for ≥ 1 joint contributed the most (OR = 20.00, P = 0.0044), but the ACR/EULAR criteria did not contribute to RA diagnosis (P = 0.57). Ultrasound findings contributed to RA diagnosis in clinical practice. The contributing factors are different in the presence or absence of seropositivity, and ultrasound complementation was particularly useful in seronegative RA patients.

Differing ERP patterns caused by suction and puff stimuli.

PubMed

Choi, Mi-Hyun; Kim, Hyung-Sik; Baek, Ji-Hye; Lee, Jung-Chul; Park, Sung-Jun; Jeong, Ul-Ho; Gim, Seon-Young; You, Ji Hye; Kim, Sung-Pil; Lim, Dae-Woon; Kim, Hyun-Jun; Chung, Soon-Cheol

2015-05-06

The present study compared event-related potential (ERP) patterns for two stimuli types, puff and suction, by applying these stimuli to the fingers; ERP patterns for the two stimuli were compared at C3, an area related to somatosensory perception, and at FC5, an area related to motor function. Participants were 12 healthy males in their 20s (mean age=23.1±2.0 years). One session consisted of a Control Phase (3s), a Stimulation Phase (3s), and a Rest Phase (9s). During the Stimulation Phase, a 4-psi suction or puff stimulus was applied to the first joint of the right index finger. After completion of the session, a subjective magnitude test was presented. In all phases, electroencephalography signals were recorded. We extracted maximum positive amplitude and minimum negative amplitude as well as relevant latency values for C3 and FC5 signals. Suction and puff stimuli had similar subjective magnitude scores. For both C3 and FC5, the maximum and minimum amplitude latency was reached earlier for the suction stimulus than for the puff stimulus. In conclusion, when suction and puff stimuli of the same intensity were applied to the fingers, the suction stimulus caused a more sensitive response in the somatosensory area (C3) and motor area (FC5) than did the puff stimulus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Percutaneous distraction lengthening in brachymetacarpia.

PubMed

Volpi, Alexander D; Fragomen, Austin T

2011-08-08

Brachymetacarpia is a condition manifesting a shortened metacarpal that is caused by early closure of the epiphyseal plate and believed to arise idiopathically. The correction for brachymetacarpia is usually for cosmetic reasons as brachymetacarpia does not impair function. The literature indicates several different approaches to lengthening digits, including single-stage lengthening and rapid distraction lengthening with a bone graft. However, gradual distraction is the preferred method due to excellent cosmetic outcomes and few postoperative complications. This article reports a case of brachymetacarpia treated with distraction lengthening using a minimally invasive, percutaneous approach. A 16-year-old girl presented with a shortened left ring finger and underwent surgery to correct the deformity. The left ring finger measured 12 mm shorter than her right ring finger; however, there was normal mobility at the joints. In the operating room, an external fixator was attached using 4 self-drilling, self-tapping pins through several 3-mm skin incisions. The total fixation time was 14 weeks; however, the achieved length of 12 mm was achieved 6 weeks postoperatively. The healing index of the fixation period was 81 days/cm. The postoperative course and fixation period were uneventful, with no complications except for 2 pin infections that were treated with oral antibiotics. The method of gradual distraction lengthening in this case successfully achieved the desired length and yielded an excellent cosmetic result. Copyright 2011, SLACK Incorporated.

Characterization of an air jet haptic lump display.

PubMed

Bianchi, Matteo; Gwilliam, James C; Degirmenci, Alperen; Okamura, Allison M

2011-01-01

During manual palpation, clinicians rely on distributed tactile information to identify and localize hard lumps embedded in soft tissue. The development of tactile feedback systems to enhance palpation using robot-assisted minimally invasive surgery (RMIS) systems is challenging due to size and weight constraints, motivating a pneumatic actuation strategy. Recently, an air jet approach has been proposed for generating a lump percept. We use this technique to direct a thin stream of air through an aperture directly on the finger pad, which indents the skin in a hemispherical manner, producing a compelling lump percept. We hypothesize that the perceived parameters of the lump (e.g. size and stiffness) can be controlled by jointly adjusting air pressure and the aperture size through which air escapes. In this work, we investigate how these control variables interact to affect perceived pressure on the finger pad. First, we used a capacitive tactile sensor array to measure the effect of aperture size on output pressure, and found that peak output pressure increases with aperture size. Second, we performed a psychophysical experiment for each aperture size to determine the just noticeable difference (JND) of air pressure on the finger pad. Subject-averaged pressure JND values ranged from 19.4-24.7 kPa, with no statistical differences observed between aperture sizes. The aperture-pressure relationship and the pressure JND values will be fundamental for future display control.

Soft tissue distraction using pentagonal frame for long-standing traumatic flexion deformity of interphalangeal joints.

PubMed

Nazerani, Shaharm; Keramati, Mohammad Reza; Vahedian, Jalal; Fereshtehnejad, Seyed-Mohammad

2012-01-01

Interphalangeal joint contracture is a challenging complication of hand trauma, which reduces the functional capacity of the entire hand. In this study we evaluated the results of soft tissue distraction with no collateral ligament transection or volar plate removal in comparison with traditional operation of contracture release and partial ligament transection and volar plate removal. In this prospective study, a total of 40 patients in two equal groups (A and B) were studied. Patients suffering from chronic flexion contracture of abrasive traumatic nature were included. Group A were treated by soft tissue distraction using pentagonal frame technique and in Group B the contracture release was followed by finger splinting. Analyzed data revealed a significant difference between the two groups for range of motion in the proximal interphalangeal joints (P less than 0.05), while it was not meaningful in the distal interphalangeal joints (P larger than 0.05). There was not a significant difference in the degrees of flexion contracture between groups (P larger than 0.05). Regression analysis showed that using pentagonal frame technique significantly increased the mean improvement in range of motion of proximal interphalangeal joints (P less than 0.001), while the higher the preoperative flexion contracture was observed in proximal interphalangeal joints, the lower improvement was achieved in range of motion of proximal interphalangeal joints after intervention (P less than 0.001). Soft tissue distraction using pentagonal frame technique with gradual and continuous collateral ligament and surrounding joint tissues distraction combined with skin Z-plasty significantly improves the range of motion in patients with chronic traumatic flexion deformity of proximal and/or distal interphalangeal joints.

[Treatment of ulnar collateral ligament avulsion fracture of thumb metacarpophalangeal joint using a combination of Kirschner wire and silk tension band].

PubMed

Gao, Shunhong; Feng, Shiming; Jiao, Cheng

2012-12-01

To investigate the effectiveness of Kirschner wire combined with silk tension band in the treatment of ulnar collateral ligament avulsion fracture of the thumb metacarpophalangeal joint. Between September 2008 and October 2011, 14 patients with ulnar collateral ligament avulsion fracture of the thumb metacarpophalangeal joint were treated using a combination of Kirschner wire and silk tension band. There were 8 males and 6 females, aged 23-55 years (mean, 40.8 years). The causes of injury were machinery twist injury in 5 cases, manual twist injury in 4 cases, falling in 4 cases, sports injury in 1 case. The time from injury to operation was 2 hours-14 days. All the patients presented pain over the ulnar aspect of the metacarpophalangeal joint of the thumb, limitation of motion, and joint instability with pinch and grip. The lateral stress testing of the metacarpophalangeal joint was positive. Function training was given at 2 weeks after operation. All incisions healed by first intention. The lateral stress testing of the metacarpophalangeal joint was negative. All the patients were followed up 6-18 months (mean, 13.1 months). The X-ray films showed good fracture reduction and healing with an average time of 7 weeks (range, 4-10 weeks). At last follow-up, the thumbs had stable flexion and extension of the metacarpophalangeal joint, normal opposition function and grip and pinch strengths. According to Saetta et al. criteria for functional assessment, the results were excellent in 11 cases and good in 3 cases; the excellent and good rate was 100%. It is an easy and simple method to treat ulnar collateral ligament avulsion fracture of the thumb metacarpophalangeal joint using Kirschner wire combined with silk tension band, which can meet the good finger function.

Dupuytren contracture recurrence project: reaching consensus on a definition of recurrence.

PubMed

Felici, N; Marcoccio, I; Giunta, R; Haerle, M; Leclercq, C; Pajardi, G; Wilbrand, S; Georgescu, A V; Pess, G

2014-12-01

The aim of this study was to determine a definition of recurrence of Dupuytren disease that could be utilized for the comparison of the results independently from the treatment used. 24 hand surgeons from 17 countries met in an international consensus conference. The participants used the Delphi method to evaluate a series of statements: (1) the need for defining recurrence, (2) the concept of recurrence applied to the Tubiana staging system, (3) the concept of recurrence applied to each single treated joint, and (4) the concept of recurrence applied to the finger ray. For each item, the possible answer was given on a scale of 1-5: 1=maximum disagreement; 2=disagreement; 3=agreement; 4=strong agreement; 5=absolute agreement. There was consensus on disagreement if 1 and 2 comprised at least 66% of the recorded answers and consensus on agreement if 3, 4 and 5 comprised at least 66% of the recorded answers. If a threshold of 66% was not reached, the related statement was considered "not defined". A need for a definition of recurrence was established. The presence of nodules or cords without finger contracture was not considered an indication of recurrence. The Tubiana staging system was considered inappropriate for reporting recurrence. Recurrence was best determined by the measurement of a specific joint, rather than a total ray. Time 0 occurred between 6 weeks and 3 months. Recurrence was defined as a PED of more than 20° for at least one of treated joint, in the presence of a palpable cord, compared to the result obtained at time 0. This study determined the need for a standard definition of recurrence and reached consensus on that definition, which we should become the standard for the reporting of recurrence. If utilized in subsequent publications, this will allow surgeons to compare different techniques and make is easier to help patients make an informed choice. © Georg Thieme Verlag KG Stuttgart · New York.

Modelling of the mechanical behavior of a polyurethane finger interphalangeal joint endoprosthesis after surface modification by ion implantation

NASA Astrophysics Data System (ADS)

Beliaev, A.; Svistkov, A.; Iziumov, R.; Osorgina, I.; Kondyurin, A.; Bilek, M.; McKenzie, D.

2016-04-01

Production of biocompatible implants made of polyurethane treated with plasma is very perspective. During plasma treatment the surface of polyurethane acquires unique physic-chemical properties. However such treatment may change the mechanical properties of polyurethane which may adversely affect the deformation behaviour of the real implant. Therefore careful study of the mechanical properties of the plasma-modified polyurethane is needed. In this paper, experimental observations of the elastic characteristics of plasma treated polyurethane and modelling of the deformation behaviour of polyurethane bio-implants are reported.

The effect of a therapy protocol for increasing correction of severely contracted proximal interphalangeal joints caused by dupuytren disease and treated with collagenase injection.

PubMed

Skirven, Terri M; Bachoura, Abdo; Jacoby, Sidney M; Culp, Randall W; Osterman, A Lee

2013-04-01

To determine the effect of a specific orthotic intervention and therapy protocol on proximal interphalangeal (PIP) joint contractures of greater than 40° caused by Dupuytren disease and treated with collagenase injections. All patients with PIP joints contracted at least 40° by Dupuytren disease were prospectively invited to participate in the study. Following standard collagenase injection and cord rupture by a hand surgeon, a certified hand therapist evaluated and treated each patient based on a defined treatment protocol that consisted of orthotic intervention to address residual PIP joint contracture. In addition, exercises were initiated emphasizing reverse blocking for PIP joint extension and distal interphalangeal joint flexion exercises with the PIP joint held in extension to lengthen a frequently shortened oblique retinacular ligament. Patients were assessed before injection, immediately after injection, and 1 and 4 weeks later. There were 22 fingers in 21 patients. The mean age at treatment was 63 years (range, 37-80 y). The mean baseline passive PIP joint contracture was 56° (range, 40° to 80°). At cord rupture, the mean PIP joint contracture became 22° (range, 0° to 55°). One week after cord rupture and therapy, the contracture decreased further to a mean of 12° (range, 0° to 36°). By 4 weeks, the mean contracture was 7° (range, 0° to 35°). The differences in PIP joint contracture were statistically significant at all time points except when comparing the means at 1 week and 4 weeks. The results represent an 88% improvement of the PIP joint contracture. In the short term, it appears that severe PIP joint contractures benefit from specific, postinjection orthotic intervention and targeted exercises. Therapeutic IV. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Rheumatic manifestations associated with Chikungunya virus infection: A study of 307 patients with 32-month follow-up (RHUMATOCHIK study).

PubMed

Bouquillard, Eric; Fianu, Adrian; Bangil, Marianne; Charlette, Nathalie; Ribéra, Anne; Michault, Alain; Favier, François; Simon, Fabrice; Flipo, René-Marc

2018-03-01

In the wake of the Chikungunya epidemic which struck Reunion Island in 2005 and 2006, we conducted a prospective, multicentre study (RHUMATOCHIK) whose main objective was analyse the characteristics and progression of rheumatic manifestations in patients with post-Chikungunya joint pain. A cohort of 307 consecutively included patients underwent rheumatological examinations for pain secondary to Chikungunya virus infection. The long-term evaluation was conducted by telephone survey 1 and 2 years after the onset of the viral infection. At inclusion, mean age was 54 years (24-87) and 83.1% of the patients were female. Chronic joint pain was associated with synovitis in 64.2% of the patients, affecting primarily the wrists, the proximal interphalangeal joints of the fingers, and the ankles. Attempts to detect the viral genome in joint fluid (10 patients) and synovial tissue (6 patients) using the RT-PCR technique were repeatedly unsuccessful. With a mean follow-up of 32 months, joint pain persisted in 83.1% of the patients. Functional impairment, however, was moderate, with a HAQ score of 0.44±0.5. Chikungunya virus infection is frequently the cause of joint manifestations that can persist for several months, or even several years. In some cases, the clinical symptoms closely resemble those usually associated with rheumatoid arthritis. Further studies are necessary to improve the therapeutic management of these patients. Copyright © 2017 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

High Performance EVA Glove Collaboration: Glove Injury Data Mining Effort

NASA Technical Reports Server (NTRS)

Reid, C. R.; Benson, E.; England, S.; Charvat, J.; Norcross, J. R.; McFarland, S. M.; Rajulu, S.

2015-01-01

Human hands play a significant role during Extravehicular Activity (EVA) missions and Neutral Buoyancy Lab (NBL) training events, as they are needed for translating and performing tasks in the weightless environment. Because of this high frequency usage, hand and arm related injuries are known to occur during EVA and EVA training in the NBL. The primary objectives of this investigation were to: 1) document all known EVA glove related injuries and circumstances of these incidents, 2) determine likely risk factors, and 3) recommend interventions where possible that could be implemented in the current and future glove designs. METHODS: The investigation focused on the discomforts and injuries of U.S. crewmembers who had worn the pressurized Extravehicular Mobility Unit (EMU) spacesuit and experienced 4000 Series or Phase VI glove related incidents during 1981 to 2010 for either EVA ground training or in-orbit flight. We conducted an observational retrospective case-control investigation using 1) a literature review of known injuries, 2) data mining of crew injury, glove sizing, and hand anthropometry databases, 3) descriptive statistical analyses, and finally 4) statistical risk correlation and predictor analyses to better understand injury prevalence and potential causation. Specific predictor statistical analyses included use of principal component analyses (PCA), multiple logistic regression, and survival analyses (Cox proportional hazards regression). Results of these analyses were computed risk variables in the forms of odds ratios (likelihood of an injury occurring given the magnitude of a risk variable) and hazard ratios (likelihood of time to injury occurrence). Due to the exploratory nature of this investigation, we selected predictor variables significant at p=0.15. RESULTS: Through 2010, there have been a total of 330 NASA crewmembers, from which 96 crewmembers performed 322 EVAs during 1981-2010, resulting in 50 crewmembers being injured inflight and 44 injured during 11,704 ground EVA training events. Of the 196 glove related injury incidents, 106 related to EVA and 90 to EVA training. Over these 196 incidents, 277 total injuries (126 flight; 151 training) were reported and were then grouped into 23 types of injuries. Of EVA flight injuries, 65% were commonly reported to the hand (in general), metacarpophalangeal (MCP) joint, and finger (not including thumb) with fatigue, abrasion, and paresthesia being the most common injury types (44% of total flight injuries). Training injuries totaled to more than 70% being distributed to the fingernail, MCP joint, and finger crotch with 88% of the specific injuries listed as pain, erythema, and onycholysis. Of these training injuries, when reporting pain or erythema, the most common location was the index finger, but when reporting onycholysis, it was the middle finger. Predictor variables specific to increased risk of onycholysis included: female sex (OR=2.622), older age (OR=1.065), increased duration in hours of the flight or training event (OR=1.570), middle finger length differences in inches between the finger and the EVA glove (OR=7.709), and use of the Phase VI glove (OR=8.535). Differentiation between training and flight and injury reporting during 2002-2004 were significant control variables. For likelihood of time to first onycholysis injury, there was a 24% reduction in rate of reporting for each year increase in age. Also, more experienced crewmembers, based on number of EVA flight or training events completed, were less likely to report an onycholysis injury (3% less for every event). Longer duration events also found reporting rates to occur 2.37 times faster for every hour of length. Crewmembers with larger hand size reported onycholysis 23% faster than those with smaller hand size. Finally, for every 1/10th of an inch increase in difference between the middle finger length and the glove, the rate of reporting increased by 60%. DISCUSSION: One key finding was that the Series 4000 glove had a lower injury risk than the Phase VI, which provides a platform for further evaluation. General interventions that reduce hand overexertion and repetitive use exposure through tool development, procedural changes and shorter exposures may be one mitigation path, but due to the way the training event times were reported, we cannot provide a guideline for a specific event duration change. When the finger length was different from the glove length, the risk of injury increased indicating that the use of larger finger take-ups could be contributing to injury and therefore may not be recommended. Prior to this investigation, there was one previous investigation indicating hand anthropometry may be related to onycholysis. We found different hand anthropometry variables indicated by this investigation as compared to the prior, specifically differences in middle finger length compared to glove finger length, which point more towards a sizing issue than a specific anthropometry issue. Additionally, although this investigation has identified sizing as an issue, the force and environmental-related variables of the EVA glove that could also cause injury were not accounted for.

Software for Simulating a Complex Robot

NASA Technical Reports Server (NTRS)

Goza, S. Michael

2003-01-01

RoboSim (Robot Simulation) is a computer program that simulates the poses and motions of the Robonaut a developmental anthropomorphic robot that has a complex system of joints with 43 degrees of freedom and multiple modes of operation and control. RoboSim performs a full kinematic simulation of all degrees of freedom. It also includes interface components that duplicate the functionality of the real Robonaut interface with control software and human operators. Basically, users see no difference between the real Robonaut and the simulation. Consequently, new control algorithms can be tested by computational simulation, without risk to the Robonaut hardware, and without using excessive Robonaut-hardware experimental time, which is always at a premium. Previously developed software incorporated into RoboSim includes Enigma (for graphical displays), OSCAR (for kinematical computations), and NDDS (for communication between the Robonaut and external software). In addition, RoboSim incorporates unique inverse-kinematical algorithms for chains of joints that have fewer than six degrees of freedom (e.g., finger joints). In comparison with the algorithms of OSCAR, these algorithms are more readily adaptable and provide better results when using equivalent sets of data.

[Sacroiliac joint dysfunction presented with acute low back pain: three case reports].

PubMed

Hamauchi, Shuji; Morimoto, Daijiro; Isu, Toyohiko; Sugawara, Atsushi; Kim, Kyongsong; Shimoda, Yusuke; Motegi, Hiroaki; Matsumoto, Ryoji; Isobe, Masanori

2010-07-01

Sacroiliac joint (SIJ) can cause low back pain when its joint capsule and ligamentous tissue are damaged. We report our experience in treating three SIJ dysfunction patients presenting with acute low back pain (a 38 year-old male, a 24 year-old male, and a 32 year-old female). SIJ dysfunction was diagnosed using the one-finger test, the modified Newton test, and SIJ injection. In all three patients, lumbar MRI demonstrated slightly degenerated lumbar lesions (lumbar canal stenosis, lumbar disc hernia). Two patients had paresthesia or pain in the leg and all three patients showed iliac muscle tenderness in the groin, which was thought to be a referred symptom because of improvement after SIJ injection. The two male patients returned to work and the problems have not recurred. Although our female patient resumed daily life as a housewife, her condition recurred at intervals of 2-3 months and she required regular SIJ injections. The prevalence of SIJ dysfunction of low back pain is about 10%, so it should be considered as a differential diagnosis when treating low back pain and designing treatment for lumbar spinal disorders.

Proximal and distal muscle fatigue differentially affect movement coordination

PubMed Central

Cowley, Jeffrey C.

2017-01-01

Muscle fatigue can cause people to change their movement patterns and these changes could contribute to acute or overuse injuries. However, these effects depend on which muscles are fatigued. The purpose of this study was to determine the differential effects of proximal and distal upper extremity muscle fatigue on repetitive movements. Fourteen subjects completed a repetitive ratcheting task before and after a fatigue protocol on separate days. The fatigue protocol either fatigued the proximal (shoulder flexor) or distal (finger flexor) muscles. Pre/Post changes in trunk, shoulder, elbow, and wrist kinematics were compared to determine how proximal and distal fatigue affected multi-joint movement patterns and variability. Proximal fatigue caused a significant increase (7°, p < 0.005) in trunk lean and velocity, reduced humeral elevation (11°, p < 0.005), and increased elbow flexion (4°, p < 0.01). In contrast, distal fatigue caused small but significant changes in trunk angles (2°, p < 0.05), increased velocity of wrench movement relative to the hand (17°/s, p < 0.001), and earlier wrist extension (4%, p < 0.005). Movement variability increased at proximal joints but not distal joints after both fatigue protocols (p < 0.05). Varying movements at proximal joints may help people adapt to fatigue at either proximal or distal joints. The identified differences between proximal and distal muscle fatigue adaptations could facilitate risk assessment of occupational tasks. PMID:28235005

Development of three-dimensional prints of arthritic joints for supporting patients' awareness to structural damage.

PubMed

Kleyer, Arnd; Beyer, Laura; Simon, Christoph; Stemmler, Fabian; Englbrecht, Matthias; Beyer, Christian; Rech, Jürgen; Manger, Bernhard; Krönke, Gerhard; Schett, Georg; Hueber, Axel J

2017-02-10

Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) result in severe joint destruction and functional disability if left untreated. We aim to develop tools that help patients with RA and PsA to understand and experience the impact of inflammatory joint disease on the integrity of their (juxta-articular) bone and increase adherence to medical treatment. In this study, we used high-resolution peripheral quantitative computed tomography (HR-pQCT) to develop 3D prototypes of patients' finger joints. HR-pQCT (XtremeCT, Scanco) measurements were performed in healthy individuals and patients with inflammatory joint disease, followed by a 3D print using the objet30 printer. Healthy participants (n = 10), and patients (n = 15 with RA and 15 with PsA) underwent a detailed, standardized interview with demonstration of printed joints. Utilizing HR-pQCT images of metacarpophalangeal (MCP) heads, high quality and exact 3D prints as prototypes were created. Erosions in different sizes and the trabecular network printed in detail were visualized, demonstrating structural reduction in arthritic vs. healthy bone. After demonstration of 3D prints (healthy vs. erosive joint, visual and haptic) 26/39 (66%) participants (including healthy volunteers) were deeply affected, often quoting "shock". Of the patients with RA and PsA, 13/15 (86%) and 11/15 (73%), respectively, stated that they would rethink their attitude to medication adherence. More importantly, 21/24 patients with RA or PsA (87.5%) expressed that they would have wished to see such 3D prints during their first disease-specific conversations. Using arthro-haptic 3D printed prototypes of joints may help to better understand the impact of inflammatory arthritides on bone integrity and long-term damage.

A feasibility study of hand kinematics for EVA analysis using magnetic resonance imaging

NASA Technical Reports Server (NTRS)

Dickenson, Rueben D.; Lorenz, Christine H.; Peterson, Steven W.; Strauss, Alvin M.; Main, John A.

1992-01-01

A new method of analyzing the kinematics of joint motion is developed. Magnetic Resonance Imaging (MRI) offers several distinct advantages. Past methods of studying anatomic joint motion have usually centered on four approaches. These methods are x-ray projection, goniometric linkage analysis, sonic digitization, and landmark measurement of photogrammetry. Of these four, only x-ray is applicable for in vivo studies. The remaining three methods utilize other types of projections of inter-joint measurements, which can cause various types of error. MRI offers accuracy in measurement due to its tomographic nature (as opposed to projection) without the problems associated with x-ray dosage. Once the data acquisition of MR images was complete, the images were processed using a 3D volume rendering workstation. The metacarpalphalangeal (MCP) joint of the left index finger was selected and reconstructed into a three-dimensional graphic display. From the reconstructed volumetric images, measurements of the angles of movement of the applicable bones were obtained and processed by analyzing the screw motion of the MCP joint. Landmark positions were chosen at distinctive locations of the joint at fixed image threshold intensity levels to ensure repeatability. The primarily two dimensional planar motion of this joint was then studied using a method of constructing coordinate systems using three (or more) points. A transformation matrix based on a world coordinate system described the location and orientation of a local target coordinate system. Future research involving volume rendering of MRI data focusing on the internal kinematics of the hand's individual ligaments, cartilage, tendons, etc. will follow. Its findings will show the applicability of MRI to joint kinematics for gaining further knowledge of the hand-glove (power assisted) design for extravehicular activity (EVA).

Proximal arm kinematics affect grip force-load force coordination

PubMed Central

Vermillion, Billy C.; Lum, Peter S.

2015-01-01

During object manipulation, grip force is coordinated with load force, which is primarily determined by object kinematics. Proximal arm kinematics may affect grip force control, as proximal segment motion could affect control of distal hand muscles via biomechanical and/or neural pathways. The aim of this study was to investigate the impact of proximal kinematics on grip force modulation during object manipulation. Fifteen subjects performed three vertical lifting tasks that involved distinct proximal kinematics (elbow/shoulder), but resulted in similar end-point (hand) trajectories. While temporal coordination of grip and load forces remained similar across the tasks, proximal kinematics significantly affected the grip force-to-load force ratio (P = 0.042), intrinsic finger muscle activation (P = 0.045), and flexor-extensor ratio (P < 0.001). Biomechanical coupling between extrinsic hand muscles and the elbow joint cannot fully explain the observed changes, as task-related changes in intrinsic hand muscle activation were greater than in extrinsic hand muscles. Rather, between-task variation in grip force (highest during task 3) appears to contrast to that in shoulder joint velocity/acceleration (lowest during task 3). These results suggest that complex neural coupling between the distal and proximal upper extremity musculature may affect grip force control during movements, also indicated by task-related changes in intermuscular coherence of muscle pairs, including intrinsic finger muscles. Furthermore, examination of the fingertip force showed that the human motor system may attempt to reduce variability in task-relevant motor output (grip force-to-load force ratio), while allowing larger fluctuations in output less relevant to task goal (shear force-to-grip force ratio). PMID:26289460

Sciatica-like symptoms and the sacroiliac joint: clinical features and differential diagnosis.

PubMed

Visser, L H; Nijssen, P G N; Tijssen, C C; van Middendorp, J J; Schieving, J

2013-07-01

To compare the clinical features of patients with sacroiliac joint (SIJ)-related sciatica-like symptoms to those with sciatica from nerve root compression and to investigate the necessity to perform radiological imaging in patients with sciatica-like symptoms derived from the SIJ. Patients with pain radiating below the buttocks with a duration of 4 weeks to 1 year were included. After physical and radiological examinations, a diagnosis of SI joint-related pain, pain due to disk herniation, or a combination of these two causes was made. Patients with SIJ-related leg pain (n = 77/186) were significantly more often female, had shorter statue, a shorter duration of symptoms, and had more often pain radiating to the groin and a history of a fall on the buttocks. Muscle weakness, corkscrew phenomenon, finger-floor distance ≥25 cm, lumbar scoliosis, positive Bragard or Kemp sign, and positive leg raising test were more often present when radiologic nerve root compression was present. Although these investigations may help, MRI of the spine is necessary to discriminate between the groups. Sciatica-like symptoms derived from the SIJ can clinically mimic a radiculopathy. We suggest to perform a thorough physical examination of the spine, SI joints, and hips with additional radiological tests to exclude other causes.

Non-verbal communication through sensor fusion

NASA Astrophysics Data System (ADS)

Tairych, Andreas; Xu, Daniel; O'Brien, Benjamin M.; Anderson, Iain A.

2016-04-01

When we communicate face to face, we subconsciously engage our whole body to convey our message. In telecommunication, e.g. during phone calls, this powerful information channel cannot be used. Capturing nonverbal information from body motion and transmitting it to the receiver parallel to speech would make these conversations feel much more natural. This requires a sensing device that is capable of capturing different types of movements, such as the flexion and extension of joints, and the rotation of limbs. In a first embodiment, we developed a sensing glove that is used to control a computer game. Capacitive dielectric elastomer (DE) sensors measure finger positions, and an inertial measurement unit (IMU) detects hand roll. These two sensor technologies complement each other, with the IMU allowing the player to move an avatar through a three-dimensional maze, and the DE sensors detecting finger flexion to fire weapons or open doors. After demonstrating the potential of sensor fusion in human-computer interaction, we take this concept to the next level and apply it in nonverbal communication between humans. The current fingerspelling glove prototype uses capacitive DE sensors to detect finger gestures performed by the sending person. These gestures are mapped to corresponding messages and transmitted wirelessly to another person. A concept for integrating an IMU into this system is presented. The fusion of the DE sensor and the IMU combines the strengths of both sensor types, and therefore enables very comprehensive body motion sensing, which makes a large repertoire of gestures available to nonverbal communication over distances.

Place of the reposition flap in the treatment of distal amputations of the fingers.

PubMed

Sbai, Mohamed Ali; M'chirgui, Mayssa El; Maalla, Riadh; Khorbi, Adel

2017-08-01

Distal finger amputations pose a therapeutic problem with the distal fragment quality. Reimplantation remains the reference treatment for functional and aesthetic recovery of the hand. The interest of this study is to propose the reposition flap as an alternative to different hedging techniques in the proximal stump, in many situations where revascularization is impossible. It consists in osteosynthesis of the bone fragment and its coverage by a pedicled local flap. The technique of reposition flap was evaluated retrospectively between 2003 and 2016 through a study of 13 patients compiled in Nabeul orthopedic department. For each patient, the sensitivity, the pulp trophicity, the interphalangeal mobility, the digital length, the appearance of the nail and radiological consolidation were evaluated. The reposition flap keeps more than 80% of the length of p3. This procedure improves nail aesthetics in comparison with the regularizations. There is no significant difference in sensitivity of the pulp or of the mobility of the distal inter-phalangeal (DIP) joint as a function of the technique studied. However there is a significant difference in average test of the Quick Dash (350 against 500 for regularizations). The reposition flap seems to be a good alternative to regularization in the context of trans-p3 fingers amputations, in which the distal fragment is not revascularizable. It allows better aesthetic and functional results. Copyright © 2017 Daping Hospital and the Research Institute of Surgery of the Third Military Medical University. Production and hosting by Elsevier B.V. All rights reserved.

Confirmation of Down syndrome critical region by FISH analysis in a patient with add(21)(p11)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsumoto, Naomichi; Niikawa, Norio; Mikawa, Makoto

1995-12-04

We have studied a patient with clinical Down syndrome (DS) who has a mosaic 46, XX/46, XX, 21p+ karyotype. The patient was born at 39 weeks of gestation with a birth weight of 3,025 g to healthy parents. At age 2 months, she was diagnosed clinically to have DS; she had flat facies, upslanted palpebral fissures, epicanthal folds, telecanthus, flat nasal bridge, abnormal dentition, malformed ears, short neck, short fingers, clinodactyly with single flexion crease of the fifth fingers, hyperextension of joints, pes planus, distal axial triradii, and bilateral tibial arch patterns. Chromosome analysis showed mosaicism consisting of a normalmore » 46,XX cell line and a line with a 21p+ chromosome, the final karyotype being mos46,XX[57]/46,XX,add(21)(p11)[43]. Although the origin of an additional segment on chromosome 21 was not identified with conventional banding analyses, it was suspected to represent partial trisomy 21 on the basis of clinical manifestations. 6 refs., 2 figs.« less

Silicone infusion tubing instead of Hunter rods for two-stage zone 2 flexor tendon reconstruction in a resource-limited surgical environment.

PubMed

Kibadi, K; Moutet, F

2017-10-01

The authors describe their experience using silicone infusion tubing in place of Hunter rods for two-stage zone 2 flexor tendon reconstruction in a resource-limited surgical environment. This case report features a 47-year-old, right-handed man who had no active PIP and DIP joint flexion in four fingers of the right hand 5 months after an injury. During the first repair stage, the A2 and A4 pulleys were reconstructed using an extensor retinaculum graft. An infusion tube was inserted instead of Hunter rods. During the second stage, formation of a digital neo-canal around the infusion tubing was observed. The infusion tubing was removed and replaced with a palmaris longus tendon graft according to the conventional technique. Physiotherapy and rehabilitation followed surgery. At 6 months, very significant progress had been made with complete recovery of PIP and DIP flexion in the four fingers. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

Using postural synergies to animate a low-dimensional hand avatar in haptic simulation.

PubMed

Mulatto, Sara; Formaglio, Alessandro; Malvezzi, Monica; Prattichizzo, Domenico

2013-01-01

A technique to animate a realistic hand avatar with 20 DoFs based on the biomechanics of the human hand is presented. The animation does not use any sensor glove or advanced tracker with markers. The proposed approach is based on the knowledge of a set of kinematic constraints on the model of the hand, referred to as postural synergies, which allows to represent the hand posture using a number of variables lower than the number of joints of the hand model. This low-dimensional set of parameters is estimated from direct measurement of the motion of thumb and index finger tracked using two haptic devices. A kinematic inversion algorithm has been developed, which takes synergies into account and estimates the kinematic configuration of the whole hand, i.e., also of the fingers whose end tips are not directly tracked by the two haptic devices. The hand skin is deformable and its deformation is computed using a linear vertex blending technique. The proposed synergy-based animation of the hand avatar involves only algebraic computations and is suitable for real-time implementation as required in haptics.

Dexterous programmable robot and control system

NASA Astrophysics Data System (ADS)

Engler, Charles D., Jr.

1995-09-01

An anatomically correct, humanlike, mechanical arm and hand is provided that an operator can control to perform with the dexterity and compliance of a human hand. Being humanlike and robotic enhances the device's control and gripper dexterity. Control of the movement of the arm and hand is performed or guided by a 'teach glove' worn by the operator. As he or she performs some hand manipulation, a controller stores signals from sensors on the exoskeleton. The sensors monitor the operator's finger-joint movement positions. These values are later translated into actuator control signals for servomotors, eventually duplicating the operator's movement.

Moore-Federman syndrome and acromicric dysplasia: are they the same entity?

PubMed Central

Winter, R M; Patton, M A; Challener, J; Mueller, R F; Baraitser, M

1989-01-01

Four unrelated patients are reported with short stature, stiffness of the joints, short fingers, inability to make a fist, and thickened skin on the forearms. Investigations have failed to show a lysosomal storage disorder and radiographs show non-specific changes with a delayed carpal bone age. The clinical features in the four children are very similar to the recently described acromicric dysplasia. There are also similarities to Moore-Federman syndrome which has only been described in one family. The case is made that acromicric dysplasia and Moore-Federman syndrome are the same entity. Images PMID:2732993

Multiple myxoid cysts secondary to occupation.

PubMed

Connolly, M; de Berker, D A R

2006-05-01

We report the case of a 50-year-old woman who presented with eight digital myxoid cysts (DMCs) involving the fingers of both hands. They developed within 12 months of the patient starting a job that involved pushing a garment into an embroidery mould, thus exerting a downward force on the fingertips. The pressure exerted from this force could have potentially damaged the joint synovial capsule, leading to rupture and loss of synovial gel, thus inducing myxoid cysts. This case suggests that DMCs may be related to occupation, and to our knowledge, this is only the second reported case of occupationally induced DMCs.

Treatment strategy for sacroiliac joint-related pain at or around the posterior superior iliac spine.

PubMed

Murakami, Eiichi; Kurosawa, Daisuke; Aizawa, Toshimi

2018-02-01

Pain at or around the posterior superior iliac spine (PSIS) is characteristic of sacroiliac joint (SIJ) -related pain. This pain can be treated by either a peri- or intra-articular injection into the joint, with the former being much easier to perform. We investigated whether peri- or intra-articular injections were more frequently effective in patients with SIJ-related pain, and aimed to create an efficient treatment strategy for SIJ-related pain at or around the PSIS. Prospective case-control study. We evaluated 85 patients with pain at or around the posterior superior iliac spine as indicated by the one finger test. First, we performed a peri-articular sacroiliac joint injection. If it was ineffective, an intra-articular injection was later given. Groin pain, sitting pain, sacroiliac joint shear test results, and posterior superior iliac spine and sacro-tuberous ligament tenderness were also compared between patients for whom a peri- or intra-articular injection was effective. Seventy-two (85%) of 85 patients had an effective injection. Out of these 72 patients, 58 (81%) had a positive peri-articular injection and 14 (19%) had a positive intra-articular injection. Four items, excluding tenderness of the sacro-tuberous ligament had no significant difference between these two injection types. To treat sacroiliac joint-related pain at or around the posterior superior iliac spine, a peri-articular injection should be performed first, and only if it is not effective should an intra-articular injection be administered. Using this strategy, we expect that most patients with sacroiliac joint-related pain will be efficiently diagnosed and treated. Copyright © 2017 Elsevier B.V. All rights reserved.

Radiation Synovectomy: an effective alternative treatment for inflamed small joints.

PubMed

Karavida, N; Notopoulos, A

2010-01-01

An inflamed painful joint is one of the most common indications for the patient to be referred to a rheumatologist or an orthopedician. In relation to the aetiology, the therapeutic approach might be systemic, local or a combination of them in some cases, always with the thought of balancing risk with benefit for the patient. In all cases, independently of the cause, the goal of therapy is to improve the quality of life through the reduction of pain, improvement of mobility and preservation of function. Nuclear Medicine has to offer Radiosynoviorthesis, an effective alternative procedure for treating inflamed small joints. Various radionuclides are available for radiosynoviorthesis. Their selection depends on the size of the joint to be treated. Small joints are mainly treated with [169Er] erbium under a fluoroscopic or sonographic guidance, usually with a simultaneous instillation of a corticoid. Candidates for radiosynoviorthesis should have been under a six-month systemic treatment without encouraging results or should have undergone at least one unsuccessful intra-articular injection of a long acting glucocorticoid. Since 1973, when [169Er] erbium was firstly suggested as a therapeutic agent for radiosynoviorthesis of the finger joints, there has been quite enough experience in its' application. It has been found to be cost effective in providing long term relief of pain and deformity of the inflamed joints in comparison to other therapeutic approaches. Additionally, there is no radiation risk and can be performed on an out patient basis. Therefore it can stand as an effective alternative procedure for treating early stages of chronic synovitis in RA (rheumatoid arthritis) patients, with minor damage of the cartilage and the adjacent bones, and for synovitis secondary to inflammatory arthropathies.

Population Coding of Forelimb Joint Kinematics by Peripheral Afferents in Monkeys

PubMed Central

Umeda, Tatsuya; Seki, Kazuhiko; Sato, Masa-aki; Nishimura, Yukio; Kawato, Mitsuo; Isa, Tadashi

2012-01-01

Various peripheral receptors provide information concerning position and movement to the central nervous system to achieve complex and dexterous movements of forelimbs in primates. The response properties of single afferent receptors to movements at a single joint have been examined in detail, but the population coding of peripheral afferents remains poorly defined. In this study, we obtained multichannel recordings from dorsal root ganglion (DRG) neurons in cervical segments of monkeys. We applied the sparse linear regression (SLiR) algorithm to the recordings, which selects useful input signals to reconstruct movement kinematics. Multichannel recordings of peripheral afferents were performed by inserting multi-electrode arrays into the DRGs of lower cervical segments in two anesthetized monkeys. A total of 112 and 92 units were responsive to the passive joint movements or the skin stimulation with a painting brush in Monkey 1 and Monkey 2, respectively. Using the SLiR algorithm, we reconstructed the temporal changes of joint angle, angular velocity, and acceleration at the elbow, wrist, and finger joints from temporal firing patterns of the DRG neurons. By automatically selecting a subset of recorded units, the SLiR achieved superior generalization performance compared with a regularized linear regression algorithm. The SLiR selected not only putative muscle units that were responsive to only the passive movements, but also a number of putative cutaneous units responsive to the skin stimulation. These results suggested that an ensemble of peripheral primary afferents that contains both putative muscle and cutaneous units encode forelimb joint kinematics of non-human primates. PMID:23112841

Low Level Laser Therapy for chronic knee joint pain patients.

PubMed

Nakamura, Takashi; Ebihara, Satoru; Ohkuni, Ikuko; Izukura, Hideaki; Harada, Takashi; Ushigome, Nobuyuki; Ohshiro, Toshio; Musha, Yoshiro; Takahashi, Hiroshi; Tsuchiya, Kazuaki; Kubota, Ayako

2014-12-27

Chronic knee joint pain is one of the most frequent complaints which is seen in the outpatient clinic in our medical institute. In previous studies we have reported the benefits of low level laser therapy (LLLT) for chronic pain in the shoulder joints, elbow, hand, finger and the lower back. The present study is a report on the effects of LLLT for chronic knee joint pain. Over the past 5 years, 35 subjects visited the outpatient clinic with complaints of chronic knee joint pain caused by the knee osteoarthritis-induced degenerative meniscal tear. They received low level laser therapy. A 1000 mW semi-conductor laser device was used to deliver 20.1 J/cm(2) per point in continuous wave at 830nm, and four points were irradiated per session (1 treatment) twice a week for 4 weeks. A visual analogue scale (VAS) was used to determine the effects of LLLT for the chronic pain and after the end of the treatment regimen a significant improvement was observed (p<0.001). After treatment, no significant differences were observed in the knee joint range of motion. Discussions with the patients revealed that it was important for them to learn how to avoid postures that would cause them knee pain in everyday life in order to have continuous benefits from the treatment. The present study demonstrated that 830 nm LLLT was an effective form of treatment for chronic knee pain caused by knee osteoarthritis. Patients were advised to undertake training involving gentle flexion and extension of the knee.

Reorganization of finger coordination patterns during adaptation to rotation and scaling of a newly learned sensorimotor transformation.

PubMed

Liu, Xiaolin; Mosier, Kristine M; Mussa-Ivaldi, Ferdinando A; Casadio, Maura; Scheidt, Robert A

2011-01-01

We examined how people organize redundant kinematic control variables (finger joint configurations) while learning to make goal-directed movements of a virtual object (a cursor) within a low-dimensional task space (a computer screen). Subjects participated in three experiments performed on separate days. Learning progressed rapidly on day 1, resulting in reduced target capture error and increased cursor trajectory linearity. On days 2 and 3, one group of subjects adapted to a rotation of the nominal map, imposed either stepwise or randomly over trials. Another group experienced a scaling distortion. We report two findings. First, adaptation rates and memory-dependent motor command updating depended on distortion type. Stepwise application and removal of the rotation induced a marked increase in finger motion variability but scaling did not, suggesting that the rotation initiated a more exhaustive search through the space of viable finger motions to resolve the target capture task than did scaling. Indeed, subjects formed new coordination patterns in compensating the rotation but relied on patterns established during baseline practice to compensate the scaling. These findings support the idea that the brain compensates direction and extent errors separately and in computationally distinct ways, but are inconsistent with the idea that once a task is learned, command updating is limited to those degrees of freedom contributing to performance (thereby minimizing energetic or similar costs of control). Second, we report that subjects who learned a scaling while moving to just one target generalized more narrowly across directions than those who learned a rotation. This contrasts with results from whole-arm reaching studies, where a learned scaling generalizes more broadly across direction than rotation. Based on inverse- and forward-dynamics analyses of reaching with the arm, we propose the difference in results derives from extensive exposure in reaching with familiar arm dynamics versus the novelty of the manual task.

[Reconstruction of the extensor pollicis longus tendon by transposition of the extensor indicis tendon].

PubMed

Loos, A; Kalb, K; Van Schoonhoven, J; Landsleitner Dagger, B

2003-12-01

Rupture of the extensor pollicis longus-tendon (EPL) is a frequent complication after distal radius fractures. Other traumatic and non-traumatic reasons for this tendon lesion are known, including a theory about a disorder in the blood supply to the tendon itself. We examined 40 patients after reconstruction of the EPL-tendon in a mean follow-up time of 30 months. All patients were clinically examined and a DASH questionnaire was answered by all patients. The method to reconstruct the EPL-tendon was the transposition of the extensor indicis-tendon. After the operations the thumb was put in a splint for four weeks in a "hitch-hiker's-position". 31 ruptures of the tendon (77.5 %) were a result of trauma. In 20 of them (50 %) a distal radius fracture had occurred. Clinical examination included measurements of the movement of the thumb- and index-finger joints, the grip strength and the maximal span of the hand. Significant differences were not found. The isolated extension of the index finger was possible in all patients. But it was reduced in ten cases which represent 25 %. Our results were evaluated by the Geldmacher score to evaluate the reconstruction of the EPL-tendon. 20 % excellent, 65 % good, 12.5 % fair and 2.5 % poor results were reached. The Geldmacher score was used critically. We suggest its modification for the evaluation of thumb abduction. The DASH score reached a functional value of ten points which represents a very good result. In conclusion the extensor indicis-transposition is a safe method to reconstruct the EPL-tendon. Its substantial advantage is taking a healthy muscle as the motor, thereby avoiding the risk of using a degenerated muscle in late tendon reconstruction. A powerful extension of the index finger will be maintained by physical education. Generally, the loss of the extension of the index finger is negligible. It does not disturb the patients. But it has to be discussed with the patient before the operation.

Hand synergies during reach-to-grasp.

PubMed

Mason, C R; Gomez, J E; Ebner, T J

2001-12-01

An emerging viewpoint is that the CNS uses synergies to simplify the control of the hand. Previous work has shown that static hand postures for mimed grasps can be described by a few principal components in which the higher order components explained only a small fraction of the variance yet provided meaningful information. Extending that earlier work, this study addressed whether the entire act of grasp can be described by a small number of postural synergies and whether these synergies are similar for different grasps. Five right-handed adults performed five types of reach-to-grasps including power grasp, power grasp with a lift, precision grasp, and mimed power grasp and mimed precision grasp of 16 different objects. The object shapes were cones, cylinders, and spindles, systematically varied in size to produce a large range of finger joint angle combinations. Three-dimensional reconstructions of 21 positions on the hand and wrist throughout the reach-to-grasp were obtained using a four-camera video system. Singular value decomposition on the temporal sequence of the marker positions was used to identify the common patterns ("eigenpostures") across the 16 objects for each task and their weightings as a function of time. The first eigenposture explained an average of 97.3 +/- 0.89% (mean +/- SD) of the variance of the hand shape, and the second another 1.9 +/- 0.85%. The first eigenposture was characterized by an open hand configuration that opens and closes during reach. The second eigenposture contributed to the control of the thumb and long fingers, particularly in the opening of the hand during the reach and the closing in preparation for object grasp. The eigenpostures and their temporal evolutions were similar across subjects and grasps. The higher order eigenpostures, although explaining only small amounts of the variance, contributed to the movements of the fingers and thumb. These findings suggest that much of reach-to-grasp is effected using a base posture with refinements in finger and thumb positions added in time to yield unique hand shapes.

"Palmar pivot flap" for resurfacing palmar lateral defects of the fingers.

PubMed

Yam, Andrew; Peng, Yeong-Pin; Pho, Robert Wan-Heng

2008-12-01

Soft tissue defects on the lateral borders of the digits are difficult to reconstruct using local or local-regional flaps. We describe a "palmar pivot flap" to resurface an adjacent defect on the palmar-lateral aspect of the digit. The surgical technique is described. This flap is an axial pattern flap based on the subcutaneous transverse branches of the digital artery. The flap is pivoted up to 90 degrees on the neurovascular bundle in its base, into an adjacent defect. The flap can be raised from either the proximal or the middle phalangeal segments. It can cover defects sited from the level of the proximal interphalangeal joint up to the fingertip. The donor defect is limited to the same digit and is covered with a full-thickness skin graft. We have used this flap on 3 patients with defects at the middle phalangeal segment, the distal interphalangeal joint, and the fingertip. All healed primarily. One patient had a mild flexion contracture of the proximal interphalangeal joint, whereas the other 2 had no complications. The patients with distal interphalangeal joint and fingertip defects had excellent sensation in the flap (2-point discrimination of 5-6 mm). The palmar pivot flap is useful for resurfacing otherwise difficult defects on the lateral borders of the digits around and distal to the proximal interphalangeal joint, including those at the fingertip. It provides sensate, glabrous skin. The donor defect is on the same digit and is well hidden, producing an aesthetic and functional reconstruction.

Development of Korean Academy of Medical Sciences Guideline for rating physical disability of upper extremity.

PubMed

Park, Jung Ho; Kim, Hee-Chun; Lee, Jae Hoon; Kim, Jin Soo; Roh, Si Young; Yi, Cheol Ho; Kang, Yoon Kyoo; Kwon, Bum Sun

2009-05-01

While the lower extremities support the weight and move the body, the upper extremities are essential for the activities of daily living, which require many detailed movements. Therefore, a disability of the upper extremity function should include a limitation of all motions of the joints and sensory loss, which affects the activities. In this study, disabilities of the upper extremities were evaluated according to the following conditions: 1) amputation, 2) joint contracture, 3) diseases of upper extremity, 4) weakness, 5) sensory loss of the finger tips, and 6) vascular and lymphatic diseases. The order of 1) to 6) is the order of major disability and there is no need to evaluate a lower order disability when a higher order one exists in the same joint or a part of the upper extremity. However, some disabilities can be either added or substituted when there are special contributions from multiple disabilities. An upper extremity disability should be evaluated after the completion of treatment and full adaptation when further functional changes are not expected. The dominance of the right or left hand before the disability should not be considered when there is a higher rate of disability.

Long-term outcomes of destructive seronegative (rheumatoid) arthritis - description of four clinical cases.

PubMed

Nikiphorou, Elena; Sjöwall, Christopher; Hannonen, Pekka; Rannio, Tuomas; Sokka, Tuulikki

2016-06-03

Seronegative rheumatoid arthritis is associated with a milder course of progression compared to seropositive disease. However, long-term follow-up data of the clinical course of seronegative rheumatoid arthritis are sparse. Here we describe four cases with a rare disease entity of aggressive destructive seronegative (rheumatoid) arthritis with 20-35 years of follow-up. The four cases are women with an initial presentation of seronegative rheumatoid arthritis in 1980-1996 and have received disease-modifying anti-rheumatic drugs since the diagnosis. In all cases, the condition has been refractory to treatments and evolved into a severe disease with destructions of the wrists, sub-talar and ankle joints, as well as large joints but not small joints of fingers and toes. All cases are negative with regard to rheumatoid factor, anti-cyclic citrullinated peptide antibodies and antibodies against carbamylated proteins. This report adds to the existing literature, making the reader aware of this sub-type of inflammatory arthritis which despite being seronegative, can have devastating disease consequences. The report highlights the need for further research into this field in order to better understand this disease sub-type, the pathogenesis, disease course and outcomes.

Finger tapping ability in healthy elderly and young adults.

PubMed

Aoki, Tomoko; Fukuoka, Yoshiyuki

2010-03-01

The maximum isometric force production capacity of the fingers decreases with age. However, little information is available on age-related changes in dynamic motor capacity of individual fingers. The purpose of this study was to compare the dynamic motor function of individual fingers between elderly and young adults using rapid single-finger and double-finger tapping. Fourteen elderly and 14 young adults performed maximum frequency tapping by the index, middle, ring, or little finger (single-finger tapping) and with alternate movements of the index-middle, middle-ring, or ring-little finger-pair (double-finger tapping). The maximum pinch force between the thumb and each finger, tactile sensitivity of each fingertip, and time taken to complete a pegboard test were also measured. Compared with young subjects, the older subjects had significantly slower tapping rates in all fingers and finger-pairs in the tapping tasks. The age-related decline was also observed in the tactile sensitivities of all fingers and in the pegboard test. However, there was no group difference in the pinch force of any finger. The tapping rate of each finger did not correlate with the pinch force or tactile sensitivity for the corresponding finger in the elderly subjects. Maximum rate of finger tapping was lower in the elderly adults compared with the young adults. The decline of finger tapping ability in elderly adults seems to be less affected by their maximum force production capacities of the fingers as well as tactile sensitivities at the tips of the fingers.

Hand digit control in children: motor overflow in multi-finger pressing force vector space during maximum voluntary force production.

PubMed

Shim, Jae Kun; Karol, Sohit; Hsu, Jeffrey; de Oliveira, Marcio Alves

2008-04-01

The aim of this study was to investigate the contralateral motor overflow in children during single-finger and multi-finger maximum force production tasks. Forty-five right handed children, 5-11 years of age produced maximum isometric pressing force in flexion or extension with single fingers or all four fingers of their right hand. The forces produced by individual fingers of the right and left hands were recorded and analyzed in four-dimensional finger force vector space. The results showed that increases in task (right) hand finger forces were linearly associated with non-task (left) hand finger forces. The ratio of the non-task hand finger force magnitude to the corresponding task hand finger force magnitude, termed motor overflow magnitude (MOM), was greater in extension than flexion. The index finger flexion task showed the smallest MOM values. The similarity between the directions of task hand and non-task hand finger force vectors in four-dimensional finger force vector space, termed motor overflow direction (MOD), was the greatest for index and smallest for little finger tasks. MOM of a four-finger task was greater than the sum of MOMs of single-finger tasks, and this phenomenon was termed motor overflow surplus. Contrary to previous studies, no single-finger or four-finger tasks showed significant changes of MOM or MOD with the age of children. We conclude that the contralateral motor overflow in children during finger maximum force production tasks is dependent upon the task fingers and the magnitude and direction of task finger forces.

Flexible, task-dependent use of sensory feedback to control hand movements

PubMed Central

Knill, David C.; Bondada, Amulya; Chhabra, Manu

2011-01-01

We tested whether changing accuracy demands for simple pointing movements leads humans to adjust the feedback control laws that map sensory signals from the moving hand to motor commands. Subjects made repeated pointing movements in a virtual environment to touch a button whose shape varied randomly from trial-to-trial – between squares, rectangles oriented perpendicular to the movement path and rectangles oriented parallel to the movement path. Subjects performed the task on a horizontal table, but saw the target configuration and a virtual rendering of their pointing finger through a mirror mounted between a monitor and the table. On a one-third of trials, the position of the virtual finger was perturbed by ±1 cm either in the movement direction or perpendicular to the movement direction when the finger passed behind an occluder. Subjects corrected quickly for the perturbations despite not consciously noticing them; however, they corrected almost twice as much for perturbations aligned with the narrow dimension of a target than for perturbations aligned with the long dimension. These changes in apparent feedback gain appeared in the kinematic trajectories soon after the time of the perturbations, indicating that they reflect differences in the feedback control law used throughout the duration of movements. The results indicate that the brain adjusts its feedback control law for individual movements “on-demand” to fit task demands. Simulations of optimal control laws for a two-joint arm show that accuracy demands alone, coupled with signal dependent noise lead to qualitatively the same behavior. PMID:21273407

Injury Risk Assessment of Extravehicular Mobility Unit (EMU) Phase VI and Series 4000 Gloves During Extravehicular Activity (EVA) Hand Manipulation Tasks

NASA Technical Reports Server (NTRS)

Kilby, Melissa

2015-01-01

Functional Extravehicular Mobility Units (EMUs) with high precision gloves are essential for the success of Extravehicular Activity (EVA). Previous research done at NASA has shown that total strength capabilities and performance are reduced when wearing a pressurized EMU. The goal of this project was to characterize the human-space suit glove interaction and assess the risk of injury during common EVA hand manipulation tasks, including pushing, pinching and gripping objects. A custom third generation sensor garment was designed to incorporate a combination of sensors, including force sensitive resistors, strain gauge sensors, and shear force sensors. The combination of sensors was used to measure the forces acting on the finger nails, finger pads, finger tips, as well as the knuckle joints. In addition to measuring the forces, data was collected on the temperature, humidity, skin conductance, and blood perfusion of the hands. Testing compared both the Phase VI and Series 4000 glove against an ungloved condition. The ungloved test was performed wearing the sensor garment only. The project outcomes identified critical landmarks that experienced higher workloads and are more likely to suffer injuries. These critical landmarks varied as a function of space suit glove and task performed. The results showed that less forces were acting on the hands while wearing the Phase VI glove as compared to wearing the Series 4000 glove. Based on our findings, the engineering division can utilize these methods for optimizing the current space suit glove and designing next generation gloves to prevent injuries and optimize hand mobility and comfort.

Tenosynovitis US scoring systems follow synovitis and clinical scoring systems in RA and are responsive to change after biologic therapy.

PubMed

Vlad, Violeta; Berghea, Florian; Micu, Mihaela; Varzaru, Luminita; Bojinca, Mihai; Milicescu, Mihaela; Ionescu, Ruxandra; Naredo, Esperanza

2015-09-01

To investigate by ultrasonography (US) in a cohort of active RA patients starting biologic therapy the responsiveness of tenosynovitis of wrist and hands compared to the responsiveness of synovitis in a 6 month period follow-up, to compare the responsiveness of finger flexor tenosynovitis with the responsiveness of wrist extensor tenosynovitis and to describe the subclinical synovitis and tenosynovitis in RA patients in clinical remission. Fifty seven patients with active RA starting biologic therapy were included. Clinical, laboratory, and US evaluations were performed at baseline, 1, and 6 months. US evaluation included wrist and MCPs 2-5 joints, bilaterally for synovitis and extensor tendons compartments 2, 4, and 6 and finger flexors 2-5 for tenosynovitis. Eighteen US scores based on semiquantitative or binary grades were calculated at each visit. Responsiveness of synovitis and tenosynovitis scores was calculated using the standardized response mean (SRM). The responsiveness of US tenosynovitis was lower comparing with the responsiveness of US synovitis but both showed large effect of therapy. Furthermore, tenosynovitis responsiveness was similar to CRP responsiveness (SRM -0.90). Finger flexors tenosynovitis showed a higher responsiveness than extensor tenosynovitis on GS (-0.94 compared to -0.63) and a lower SRM on PD (-0.56 compared to -0.85). Tenosynovitis scores remission was overlapping clinical remission according to CDAI and SDAI in 100% of cases. Overall there was less subclinical tenosynovitis than subclinical synovitis at final visit according to clinical activity indices. Tenosynovitis US scoring in RA may be as good as synovitis scoring for characterization of disease activity and responsiveness.

Modified toe pulp fillet flap coverage: Better wound healing and satisfactory length preservation.

PubMed

Baek, Sang Oon; Suh, Hyo Wan; Lee, Jun Yong

2018-01-01

Amputation is commonly performed for toe necrosis secondary to peripheral vascular diseases, such as diabetes mellitus. When amputating a necrotic toe, preservation of the bony structure is important for preventing the collapse of adjacent digits into the amputated space. However, in the popular terminal Syme's amputation technique, partial amputation of the distal phalanx could cause increased tension on the wound margin. Herein, we introduce a new way to resect sufficient bony structure while maintaining the normal length, based on a morphological analysis of the toes. Unlike the pulp of the finger in the distal phalanx, the toe has abundant teardrop-shaped pulp tissue. The ratio of the vertical length to the longitudinal length in the distal phalanx was compared between the toes and fingers. Amputation was performed at the proximal interphalangeal joint level. Then, a mobilizable pulp flap was rotated 90° cephalad to replace the distal soft tissue defect. This modified toe fillet flap was performed in 5 patients. The toe pulp was found to have a vertically oriented morphology compared to that of the fingers, enabling length preservation through cephalad rotation. All defects were successfully covered without marginal ischemia. While conventional toe fillet flap coverage focuses on the principle of length preservation as the first priority, our modified method takes both wound healing and length into account. The fattiest part of the pulp is advanced to the toe tip, providing a cushioning effect and enough length to substitute for phalangeal bone loss. Our modified method led to satisfactory functional and aesthetic outcomes.

Development of an MR-compatible hand exoskeleton that is capable of providing interactive robotic rehabilitation during fMRI imaging.

PubMed

Kim, Sangjoon J; Kim, Yeongjin; Lee, Hyosang; Ghasemlou, Pouya; Kim, Jung

2018-02-01

Following advances in robotic rehabilitation, there have been many efforts to investigate the recovery process and effectiveness of robotic rehabilitation procedures through monitoring the activation status of the brain. This work presents the development of a two degree-of-freedom (DoF) magnetic resonance (MR)-compatible hand device that can perform robotic rehabilitation procedures inside an fMRI scanner. The device is capable of providing real-time monitoring of the joint angle, angular velocity, and joint force produced by the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of four fingers. For force measurement, a custom reflective optical force sensor was developed and characterized in terms of accuracy error, hysteresis, and repeatability in the MR environment. The proposed device consists of two non-magnetic ultrasonic motors to provide assistive and resistive forces to the MCP and PIP joints. With actuation and sensing capabilities, both non-voluntary-passive movements and active-voluntary movements can be implemented. The MR compatibility of the device was verified via the analysis of the signal-to-noise ratio (SNR) of MR images of phantoms. SNR drops of 0.25, 2.94, and 11.82% were observed when the device was present but not activated, when only the custom force sensor was activated, and when both the custom force sensor and actuators were activated, respectively.

Finger Interdependence: Linking the Kinetic and Kinematic Variables

PubMed Central

Kim, Sun Wook; Shim, Jae Kun; Zatsiorsky, Vladimir M.; Latash, Mark L.

2008-01-01

We studied the dependence between voluntary motion of a finger and pressing forces produced by the tips of other fingers of the hand. Subjects moved one of the fingers (task finger) of the right hand trying to follow a cyclic, ramp-like flexion-extension template at different frequencies. The other fingers (slave fingers) were restricted from moving; their flexion forces were recorded and analyzed. Index finger motion caused the smallest force production by the slave fingers. Larger forces were produced by the neighbors of the task finger; these forces showed strong modulation over the range of motion of the task finger. The enslaved forces were higher during the flexion phase of the movement cycle as compared to the extension phase. The index of enslaving expressed in N/rad was higher when the task finger moved through the more flexed postures. The dependence of enslaving on both range and direction of task finger motion poses problems for methods of analysis of finger coordination based on an assumption of universal matrices of finger inter-dependence. PMID:18255182

Interphalangeal Osteoarthritis Radiographic Simplified (iOARS) score: a radiographic method to detect osteoarthritis of the interphalangeal finger joints based on its histopathological alterations.

PubMed

Sunk, Ilse-Gerlinde; Amoyo-Minar, Love; Stamm, Tanja; Haider, Stefanie; Niederreiter, Birgit; Supp, Gabriela; Soleiman, Afschin; Kainberger, Franz; Smolen, Josef S; Bobacz, Klaus

2014-11-01

To develop a radiographic score for assessment of hand osteoarthritis (OA) that is based on histopathological alterations of the distal (DIP) and proximal (PIP) interphalangeal joints. DIP and PIP joints were obtained from corpses (n=40). Plain radiographies of these joints were taken. Joint samples were prepared for histological analysis; cartilage damage was graded according to the Mankin scoring system. A 2×2 Fisher's exact test was applied to define those radiographic features most likely to be associated with histological alterations. Receiver operating characteristic curves were analysed to determine radiographic thresholds. Intraclass correlation coefficients (ICC) estimated intra- and inter-reader variability. Spearman's correlation was applied to examine the relationship between our score and histopathological changes. Differences between groups were determined by a Student's t test. The Interphalangeal Osteoarthritis Radiographic Simplified (iOARS) score is presented. The score is based on histopathological changes of DIP and PIP joints and follows a simple dichotomy whether OA is present or not. The iOARS score relies on three equally ranked radiographic features (osteophytes, joint space narrowing and subchondral sclerosis). For both DIP and PIP joints, the presence of one x-ray features reflects interphalangeal OA. Sensitivity and specificity for DIP joints were 92.3% and 90.9%, respectively, and 75% and 100% for PIP joints. All readers were able to reproduce their own readings in DIP and PIP joints after 4 weeks. The overall agreement between the three readers was good; ICCs ranged from 0.945 to 0.586. Additionally, outcomes of the iOARS score in a hand OA cohort revealed a higher prevalence of interphalangeal joint OA compared with the Kellgren and Lawrence score. The iOARS score is uniquely based on histopathological alterations of the interphalangeal joints in order to reliably determine OA of the DIP and PIP joints radiographically. Its high specificity and sensitivity together with the dichotomous approach renders the iOARS score reliable, fast to perform and easy to apply. This tool may not only be valuable in daily clinical practice but also in clinical and epidemiological trials. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Design and preliminary evaluation of the FINGER rehabilitation robot: controlling challenge and quantifying finger individuation during musical computer game play.

PubMed

Taheri, Hossein; Rowe, Justin B; Gardner, David; Chan, Vicki; Gray, Kyle; Bower, Curtis; Reinkensmeyer, David J; Wolbrecht, Eric T

2014-02-04

This paper describes the design and preliminary testing of FINGER (Finger Individuating Grasp Exercise Robot), a device for assisting in finger rehabilitation after neurologic injury. We developed FINGER to assist stroke patients in moving their fingers individually in a naturalistic curling motion while playing a game similar to Guitar Hero. The goal was to make FINGER capable of assisting with motions where precise timing is important. FINGER consists of a pair of stacked single degree-of-freedom 8-bar mechanisms, one for the index and one for the middle finger. Each 8-bar mechanism was designed to control the angle and position of the proximal phalanx and the position of the middle phalanx. Target positions for the mechanism optimization were determined from trajectory data collected from 7 healthy subjects using color-based motion capture. The resulting robotic device was built to accommodate multiple finger sizes and finger-to-finger widths. For initial evaluation, we asked individuals with a stroke (n = 16) and without impairment (n = 4) to play a game similar to Guitar Hero while connected to FINGER. Precision design, low friction bearings, and separate high speed linear actuators allowed FINGER to individually actuate the fingers with a high bandwidth of control (-3 dB at approximately 8 Hz). During the tests, we were able to modulate the subject's success rate at the game by automatically adjusting the controller gains of FINGER. We also used FINGER to measure subjects' effort and finger individuation while playing the game. Test results demonstrate the ability of FINGER to motivate subjects with an engaging game environment that challenges individuated control of the fingers, automatically control assistance levels, and quantify finger individuation after stroke.

Revision Proximal Interphalangeal Arthroplasty: An Outcome Analysis of 75 Consecutive Cases.

PubMed

Wagner, Eric R; Luo, T David; Houdek, Matthew T; Kor, Daryl J; Moran, Steven L; Rizzo, Marco

2015-10-01

To examine the outcomes and complications associated with revision proximal interphalangeal (PIP) joint arthroplasty. An analysis of 75 consecutive revision PIP joint arthroplasties in 49 patients, performed between 1998 to 2012, was performed. The mean age at the time of surgery was 58 years. Thirty-two patients had a history of prior PIP joint trauma, and 18 patients had rheumatoid arthritis. There were 12 constrained (silicone) implants and 63 nonconstrained implants (34 pyrocarbon and 29 metal-plastic). Over the 14-year period, 19 (25%) fingers underwent a second revision surgery. Second revision surgeries were performed for infection, instability, flexion contracture, and heterotopic ossification. The 2-, 5-, and 10-year survival rates were 80%, 70%, and 70%, respectively, for patients requiring a second revision for PIP joint arthroplasty. Worse outcomes were seen with postoperative dislocations, pyrocarbon implants, and when bone grafting was required. Two operations were complicated by intraoperative fractures, but neither required stabilization. Sixteen patients undergoing revision surgery experienced a postoperative complication, including 2 infections, 1 postoperative fracture, 3 cases of heterotopic ossification, and 10 PIP joint dislocations. The volar approach and the use of a pyrocarbon implant was associated with increased rates of heterotopic ossification, whereas preoperative instability increased the rates of PIP joint dislocation following revision. At a mean of 5.3 years (range, 2-10 years) follow-up, 98% of patients had good pain relief but decreased PIP joint total arc of motion. Proximal interphalangeal joint arthroplasty in the revision setting represents a challenge for surgeons. Revision arthroplasty was associated with a 70% 5-year survival but with a high incidence of complications. Instability was associated with worse outcomes. In this series, silicone and metal-polyethylene implants had lower rates of implant failure and postoperative complications than ones made from pyrocarbon. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Estimating thumb–index finger precision grip and manipulation potential in extant and fossil primates

PubMed Central

Feix, Thomas; Kivell, Tracy L.; Pouydebat, Emmanuelle; Dollar, Aaron M.

2015-01-01

Primates, and particularly humans, are characterized by superior manual dexterity compared with other mammals. However, drawing the biomechanical link between hand morphology/behaviour and functional capabilities in non-human primates and fossil taxa has been challenging. We present a kinematic model of thumb–index precision grip and manipulative movement based on bony hand morphology in a broad sample of extant primates and fossil hominins. The model reveals that both joint mobility and digit proportions (scaled to hand size) are critical for determining precision grip and manipulation potential, but that having either a long thumb or great joint mobility alone does not necessarily yield high precision manipulation. The results suggest even the oldest available fossil hominins may have shared comparable precision grip manipulation with modern humans. In particular, the predicted human-like precision manipulation of Australopithecus afarensis, approximately one million years before the first stone tools, supports controversial archaeological evidence of tool-use in this taxon. PMID:25878134

Serum matrix metalloproteinase 3 in detecting remitting seronegative symmetrical synovitis with pitting edema syndrome: A case report.

PubMed

Kenzaka, Tsuneaki; Goda, Ken

2018-05-16

We report a case of remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome in a 71-year-old woman. She referred to our hospital with finger stiffness, edema of both hands and feet, pain of bilateral shoulder, wrist, metacarpophalangeal, proximal interphalangeal, and ankle joints. Rheumatoid factor was negative, human leukocyte antigen -B7 antigen was positive. Moreover, matrix metalloproteinase 3 (MMP-3) was high. She was diagnosed with RS3PE syndrome, and treatment with prednisolone (15 mg/d) was started. One week after prednisolone treatment initiation, CRP decreased to negative, and joint pain was almost completely resolved. However, hand stiffness persisted, and MMP-3 level was still high. Thus, prednisolone dose was increased to 20 mg/d, and the stiffness resolved. Twenty days after treatment initiation, MMP-3 was normalized. MMP-3 was more indicative of RS3PE syndrome symptoms than CRP. Thus, MMP-3 seems to be more sensitive to RS3PE syndrome symptoms.

Serum matrix metalloproteinase 3 in detecting remitting seronegative symmetrical synovitis with pitting edema syndrome: A case report

PubMed Central

Kenzaka, Tsuneaki; Goda, Ken

2018-01-01

We report a case of remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome in a 71-year-old woman. She referred to our hospital with finger stiffness, edema of both hands and feet, pain of bilateral shoulder, wrist, metacarpophalangeal, proximal interphalangeal, and ankle joints. Rheumatoid factor was negative, human leukocyte antigen -B7 antigen was positive. Moreover, matrix metalloproteinase 3 (MMP-3) was high. She was diagnosed with RS3PE syndrome, and treatment with prednisolone (15 mg/d) was started. One week after prednisolone treatment initiation, CRP decreased to negative, and joint pain was almost completely resolved. However, hand stiffness persisted, and MMP-3 level was still high. Thus, prednisolone dose was increased to 20 mg/d, and the stiffness resolved. Twenty days after treatment initiation, MMP-3 was normalized. MMP-3 was more indicative of RS3PE syndrome symptoms than CRP. Thus, MMP-3 seems to be more sensitive to RS3PE syndrome symptoms. PMID:29774220

Carpal tunnel volume changes of the wrist under distraction.

PubMed

Cho, M S; Means, K R; Shrout, J A; Segalman, K A

2008-10-01

This study attempts to determine changes in carpal canal volume with distraction across the wrist. Uniform longitudinal distraction was maintained with two external fixators on the radial and ulnar aspects of the forearm axis of five cadaver specimens. After CT scanning, volume determinations were made at 5 mm increments beginning at the lunocapitate joint to a point 1.5 cm distal to the middle finger carpometacarpal joint. There was a statistically significant decrease of the mean total carpal canal volume from 0 to 4.54 kg of distraction, with no statistically significant decrease from 0 to 2.27 kg or 2.27 to 4.54 kg. The largest decrease occurred at 15 and 20 mm distal to the proximal edge of the transverse carpal ligament corresponding to the level of the hamate hook. Reduction in mean carpal canal volume was 10.2% and 7.5% at these distances, respectively, from 0 to 4.54 kg of distraction. Progressive distraction across the wrist causes a decrease in total carpal canal volume.

Estimating thumb-index finger precision grip and manipulation potential in extant and fossil primates.

PubMed

Feix, Thomas; Kivell, Tracy L; Pouydebat, Emmanuelle; Dollar, Aaron M

2015-05-06

Primates, and particularly humans, are characterized by superior manual dexterity compared with other mammals. However, drawing the biomechanical link between hand morphology/behaviour and functional capabilities in non-human primates and fossil taxa has been challenging. We present a kinematic model of thumb-index precision grip and manipulative movement based on bony hand morphology in a broad sample of extant primates and fossil hominins. The model reveals that both joint mobility and digit proportions (scaled to hand size) are critical for determining precision grip and manipulation potential, but that having either a long thumb or great joint mobility alone does not necessarily yield high precision manipulation. The results suggest even the oldest available fossil hominins may have shared comparable precision grip manipulation with modern humans. In particular, the predicted human-like precision manipulation of Australopithecus afarensis, approximately one million years before the first stone tools, supports controversial archaeological evidence of tool-use in this taxon. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

The fickle finger of fate

PubMed Central

de la Fuente, Luis; Helms, Jill A.

2005-01-01

In this issue of the JCI, Niedermaier and colleagues demonstrate that a chromosomal inversion in mice results in dysregulation of Sonic hedgehog (Shh), such that Shh is ectopically expressed in a skeletogenic domain typically occupied by Indian hedgehog (Ihh). This molecular reversal eliminates phalangeal joint spaces, and consequently, Short digits (Dsh) heterozygotes (Dsh/+) have brachydactyly (shortened digits). Ihh is normally downregulated in regions that will become the joint space, but in Dsh/+ mice, Shh bypasses this regulatory control and persists; accordingly, cells maintain their chondrogenic fate and the developed digits are shorter than normal. The significance of these data extends far beyond the field of skeletal biology: they hint at the very real possibility that the endogenous Shh regulatory region contains a repressor designed to segregate the activity of Shh from Ihh. The existence of such a repressor provides a window into the distant past, revealing that Shh and Ihh must once have shared responsibilities in establishing tissue boundaries and orchestrating vertebrate tissue morphogenesis. PMID:15841172

State-space control of prosthetic hand shape.

PubMed

Velliste, M; McMorland, A J C; Diril, E; Clanton, S T; Schwartz, A B

2012-01-01

In the field of neuroprosthetic control, there is an emerging need for simplified control of high-dimensional devices. Advances in robotic technology have led to the development of prosthetic arms that now approach the look and number of degrees of freedom (DoF) of a natural arm. These arms, and especially hands, now have more controllable DoFs than the number of control DoFs available in many applications. In natural movements, high correlations exist between multiple joints, such as finger flexions. Therefore, discrepancy between the number of control and effector DoFs can be overcome by a control scheme that maps low-DoF control space to high-DoF joint space. Imperfect effectors, sensor noise and interactions with external objects require the use of feedback controllers. The incorporation of feedback in a system where the command is in a different space, however, is challenging, requiring a potentially difficult inverse high-DoF to low-DoF transformation. Here we present a solution to this problem based on the Extended Kalman Filter.

Effect of wrist and interphalangeal thumb movement on zone T2 flexor pollicis longus tendon tension in a human cadaver model.

PubMed

Rappaport, Patricia O; Thoreson, Andrew R; Yang, Tai-Hua; Reisdorf, Ramona L; Rappaport, Stephen M; An, Kai-Nan; Amadio, Peter C

2015-01-01

Therapy after flexor pollicis longus (FPL) repair typically mimics finger flexor management, but this ignores anatomic and biomechanical features unique to the FPL. We measured FPL tendon tension in zone T2 to identify biomechanically appropriate exercises for mobilizing the FPL. Eight human cadaver hands were studied to identify motions that generated enough force to achieve FPL movement without exceeding hypothetical suture strength. With the carpometacarpal and metacarpophalangeal joints blocked, appropriate forces were produced for both passive interphalangeal (IP) motion with 30° wrist extension and simulated active IP flexion from 0° to 35° with the wrist in the neutral position. This work provides a biomechanical basis for safely and effectively mobilizing the zone T2 FPL tendon. Our cadaver study suggests that it is safe and effective to perform early passive and active exercise to an isolated IP joint. NA. Copyright © 2015 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Integration of tactile input across fingers in a patient with finger agnosia.

PubMed

Anema, Helen A; Overvliet, Krista E; Smeets, Jeroen B J; Brenner, Eli; Dijkerman, H Chris

2011-01-01

Finger agnosia has been described as an inability to explicitly individuate between the fingers, which is possibly due to fused neural representations of these fingers. Hence, are patients with finger agnosia unable to keep tactile information perceived over several fingers separate? Here, we tested a finger agnosic patient (GO) on two tasks that measured the ability to keep tactile information simultaneously perceived by individual fingers separate. In experiment 1 GO performed a haptic search task, in which a target (the absence of a protruded line) needed to be identified among distracters (protruded lines). The lines were presented simultaneously to the fingertips of both hands. Similarly to the controls, her reaction time decreased when her fingers were aligned as compared to when her fingers were stretched and in an unaligned position. This suggests that she can keep tactile input from different fingers separate. In experiment two, GO was required to judge the position of a target tactile stimulus to the index finger, relatively to a reference tactile stimulus to the middle finger, both in fingers uncrossed and crossed position. GO was able to indicate the relative position of the target stimulus as well as healthy controls, which indicates that she was able to keep tactile information perceived by two neighbouring fingers separate. Interestingly, GO performed better as compared to the healthy controls in the finger crossed condition. Together, these results suggest the GO is able to implicitly distinguish between tactile information perceived by multiple fingers. We therefore conclude that finger agnosia is not caused by minor disruptions of low-level somatosensory processing. These findings further underpin the idea of a selective impaired higher order body representation restricted to the fingers as underlying cause of finger agnosia. Copyright © 2010 Elsevier Ltd. All rights reserved.

Single Degree-of-Freedom Exoskeleton Mechanism Design for Thumb Rehabilitation*

PubMed Central

Yihun, Yimesker; Miklos, Robert; Perez-Gracia, Alba; Reinkensmeyer, David J.; Denney, Keith; Wolbrecht, Eric T.

2014-01-01

This paper presents the kinematic design of a spatial, 1-degree-of-freedom closed linkage to be used as an exoskeleton for thumb motion. Together with an already-designed finger mechanism, it forms a robotic device for hand therapy. The goal for the exoskeleton is to generate the desired grasping and pinching path of the thumb with one degree of freedom, rather than using a system actuating all its joints independently. In addition to the path of the thumb, additional constraints are added in order to control the position and size of the exoskeleton, reducing physical and sensory interference with the user. PMID:23366289

The Use of Cryotherapy to Treat Infantile Digital Fibromatosis with a Functional Deficit: A Case Report.

PubMed

Kramer, Aviv; Har-Shai, Yaron; Metanes, Isa; Harel, Hani; Wollstein, Ronit

2018-06-01

Infantile Digital Fibromatosis (IDF) is a rare benign lesion that can affect the fingers, often appearing at birth or early on in life. Treatment is controversial due to a high recurrence rate following surgical excision, and the tendency of the lesions to regress or resolve completely after the age of one year. Functional loss has rarely been described. We describe a case of IDF with joint contracture and significant functional deficit that was treated with cryotherapy and post procedural occupational therapy with an excellent result. Indications for treatment and cryotherapy as a therapeutic modality for IDF are discussed.

Lessons Learned Through the Follow-up of the Long-Term Effects of Over-Exposure to an Ir192 Industrial Radiography Source in Bangladesh

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jalil, A.; Rabbani, G.; Hossain, M. K.

2003-02-24

An industrial radiographer was accidentally over-exposed while taking the radiograph of weld-joints of gas pipe-lines in 1985 in Bangladesh. Symptoms of high radiation exposure occurred immediately after the accident and skin erythema developed leading to progressive tissue deterioration. The consequences of this over-exposure is being followed up to assess the long-term effects of ionizing radiation on the victim. Progressive tissue deteriorations have already led to multiple surgeries and successive amputations of the finger-tips so far. Lessons learned from this accident are also reported in this paper.

Exome Sequencing of a Pedigree Reveals S339L Mutation in the TLN2 Gene as a Cause of Fifth Finger Camptodactyly.

PubMed

Deng, Hao; Deng, Sheng; Xu, Hongbo; Deng, Han-Xiang; Chen, Yulan; Yuan, Lamei; Deng, Xiong; Yang, Shengbo; Guan, Liping; Zhang, Jianguo; Yuan, Hong; Guo, Yi

2016-01-01

Camptodactyly is a digit deformity characterized by permanent flexion contracture of one or both fifth fingers at the proximal interphalangeal joints. Though over 60 distinct types of syndromic camptodactyly have been described, only one disease locus (3q11.2-q13.12) for nonsyndromic camptodactyly has been identified. To identify the genetic defect for camptodactyly in a four-generation Chinese Han family, exome and Sanger sequencings were conducted and a missense variant, c.1016C>T (p.S339L), in the talin 2 gene (TLN2) was identified. The variant co-segregated with disease in the family and was not observed in 12 unaffected family members or 1,000 normal controls, suggesting that p.S339L is a pathogenic mutation. Two asymptomatic carriers in the family indicated incomplete penetrance or more complicated compensated mechanism. Most of p.S339L carriers also have relatively benign cardiac phenotypes. Expression of wild and mutant TLN2 in HEK293 cells suggested the predominant localization in cytoplasm. Our data suggest a potential molecular link between TLN2 and camptodactyly pathogenesis.

Use of an AC induction motor system for producing finger movements in human subjects.

PubMed

Proudlock, F A; Scott, J J

1998-12-01

This report describes the set-up and evaluation of a novel system for producing precise finger movements, for tests of movement perception. The specifications were to construct a system using commercially available components that were easy to use but which offered both flexibility and also high precision control. The system was constructed around an industrial AC induction motor with an optical encoder, controlled by an AC servo digital control module that could be programmed using a simple, high-level language. This set-up fulfilled the requirements regarding position and velocity control for a range of movements and also the facility for the subject to move the joint voluntarily while still attached to the motor. However a number of problems were encountered, the most serious being the level of vibration and the inability to vary the torque during movements. The vibration was reduced to the point where it did not affect the subject, by the introduction of mechanical dampening using an anti-vibration coupling and a pneumatic splint. The torque control could not be modified during rotation and so the system could only be operated using constant torque for any given movement.

Efficacy and safety of collagenase clostridium histolyticum injection for Dupuytren contracture: short-term results from 2 open-label studies.

PubMed

Witthaut, Jörg; Jones, Graeme; Skrepnik, Nebojsa; Kushner, Harvey; Houston, Anthony; Lindau, Tommy R

2013-01-01

The JOINT I (United States) and JOINT II (Australia and Europe) studies evaluated the efficacy and safety of collagenase clostridium histolyticum (CCH) injection for the treatment of Dupuytren contracture. Both studies used identical open-label protocols. Patients with fixed-flexion contractures of metacarpophalangeal (MCP) (20° to 100°) or proximal interphalangeal (PIP) joints (20° to 80°) could receive up to three 0.58-mg CCH injections per cord (up to 5 total injections per patient). We performed standardized finger extension procedures to disrupt injected cords the next day, with follow-up 1, 2, 6, and 9 months thereafter. The primary end point (clinical success) was reduction in contracture to within 0° to 5° of full extension 30 days after the last injection. Clinical improvement was defined as 50% or more reduction from baseline contracture. Dupuytren cords affecting 879 joints (531 MCP and 348 PIP) in 587 patients were administered CCH injections at 14 U.S. and 20 Australian/European sites, with similar outcomes in both studies. Clinical success was achieved in 497 (57%) of treated joints using 1.2 ± 0.5 (mean ± SD) CCH injections per cord. More MCP than PIP joints achieved clinical success (70% and 37%, respectively) or clinical improvement (89% and 58%, respectively). Less severely contracted joints responded better than those more severely contracted. Mean change in contracture was 55° for MCP joints and 25° for PIP joints. With average contracture reductions of 73% and improvements in range of motion by 30°, most patients (92%) were "very satisfied" (71%) or "quite satisfied" (21%) with treatment. Physicians rated change from baseline as "very much improved" (47%) or "much improved" (35%). The CCH injections were well tolerated, causing no tendon ruptures or systemic reactions. Collagenase clostridium histolyticum was an effective, minimally invasive option for the treatment of Dupuytren contracture of a broad range of severities. Most treated joints (625 of 879) required a single injection. Treatment earlier in the course of disease provided improved outcomes. Therapeutic IV. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Design and preliminary evaluation of the FINGER rehabilitation robot: controlling challenge and quantifying finger individuation during musical computer game play

PubMed Central

2014-01-01

Background This paper describes the design and preliminary testing of FINGER (Finger Individuating Grasp Exercise Robot), a device for assisting in finger rehabilitation after neurologic injury. We developed FINGER to assist stroke patients in moving their fingers individually in a naturalistic curling motion while playing a game similar to Guitar Hero®a. The goal was to make FINGER capable of assisting with motions where precise timing is important. Methods FINGER consists of a pair of stacked single degree-of-freedom 8-bar mechanisms, one for the index and one for the middle finger. Each 8-bar mechanism was designed to control the angle and position of the proximal phalanx and the position of the middle phalanx. Target positions for the mechanism optimization were determined from trajectory data collected from 7 healthy subjects using color-based motion capture. The resulting robotic device was built to accommodate multiple finger sizes and finger-to-finger widths. For initial evaluation, we asked individuals with a stroke (n = 16) and without impairment (n = 4) to play a game similar to Guitar Hero® while connected to FINGER. Results Precision design, low friction bearings, and separate high speed linear actuators allowed FINGER to individually actuate the fingers with a high bandwidth of control (−3 dB at approximately 8 Hz). During the tests, we were able to modulate the subject’s success rate at the game by automatically adjusting the controller gains of FINGER. We also used FINGER to measure subjects’ effort and finger individuation while playing the game. Conclusions Test results demonstrate the ability of FINGER to motivate subjects with an engaging game environment that challenges individuated control of the fingers, automatically control assistance levels, and quantify finger individuation after stroke. PMID:24495432

Development of cylindrical-type finger force measuring system using force sensors and its characteristics evaluation

NASA Astrophysics Data System (ADS)

Kim, Hyeon-Min; Yoon, Joungwon; Shin, Hee-Suk; Kim, Gab-Soon

2012-02-01

Some patients cannot use their hands because of the paralysis of their fingers. Their fingers can recover with rehabilitative training, and the extent of rehabilitation can be judged by grasping a cylindrical-object with their fingers. At present, the cylindrical-object used in hospitals is only a plastic cylinder, which cannot measure grasping force of the fingers. Therefore, doctors must judge the extent of rehabilitation by watching patients' fingers as they grasp the plastic cylinder. In this paper, the development of two cylindrical-type finger force measuring systems with four force sensors for left hand and right hand were developed. The developed finger force measuring system can measure the grasping force of patients' each finger (forefinger, middle finger, ring finger and little finger), and the measured results could be used to judge the rehabilitation extent of a finger patient. The grasping force tests of men and women were performed using the developed cylindrical-type finger force measuring systems. The tests confirm that the average finger forces of right hand and left hand for men were about 194 N and 179 N, and for women, 108 N and 95 N.

[Treatment of trigger finger with located needle knife].

PubMed

Zhang, Qi-Feng; Yang, Jiang; Xi, Sheng-Hua

2016-07-25

To investigate the clinical effects of located needle knife in the treatment of trigger finger. The clinical data of 133 patients(145 fingers) with trigger finger underwent treatment with located needle knife from September 2010 to March 2014 were retrospectively analyzed. There were 37 males(40 fingers) and 96 females (105 fingers), aged from 18 to 71 years old with a mean of 51.8 years. Course of disease was from 1 to 19 months with an average of 8.2 months. Affected fingers included 82 thumbs, 12 index fingers, 11 middle fingers, 36 ring fingers, and 4 little fingers. According to the standard of Quinnell grade, 42 fingers were grade III, 92 fingers were grade IV, and 11 fingers were grade V. Firstly the double pipe gab was put into the distal edge of hypertrophic tendon sheath, then small knife needle was used to release the sheath proximally along the tendon line direction. The informations of wound healing and nerve injury, postoperative finger function, finger pain at 6 months were observed. The operation time was from 8 to 25 min with an average of 9.8 min. All the patients were followed up from 6 to 26 months with an average of 12.5 months. No complications such as the wound inflammation and seepage, vascular or nerve injuries were found. According to the standard of Quinnell grade, 123 fingers got excellent results, 15 good, 7 poor. It's a good choice to treat trigger finger with located needle knife in advantage of minimal invasion, simple safe operation, and it should be promoted in clinic.

An estimation of finger-tapping rates and load capacities and the effects of various factors.

PubMed

Ekşioğlu, Mahmut; İşeri, Ali

2015-06-01

The aim of this study was to estimate the finger-tapping rates and finger load capacities of eight fingers (excluding thumbs) for a healthy adult population and investigate the effects of various factors on tapping rate. Finger-tapping rate, the total number of finger taps per unit of time, can be used as a design parameter of various products and also as a psychomotor test for evaluating patients with neurologic problems. A 1-min tapping task was performed by 148 participants with maximum volitional tempo for each of eight fingers. For each of the tapping tasks, the participant with the corresponding finger tapped the associated key in the standard position on the home row of a conventional keyboard for touch typing. The index and middle fingers were the fastest fingers for both hands, and little fingers the slowest. All dominant-hand fingers, except little finger, had higher tapping rates than the fastest finger of the nondominant hand. Tapping rate decreased with age and smokers tapped faster than nonsmokers. Tapping duration and exercise had also significant effect on tapping rate. Normative data of tapping rates and load capacities of eight fingers were estimated for the adult population. In designs of psychomotor tests that require the use of tapping rate or finger load capacity data, the effects of finger, age, smoking, and tapping duration need to be taken into account. The findings can be used for ergonomic designs requiring finger-tapping capacity and also as a reference in psychomotor tests. © 2015, Human Factors and Ergonomics Society.

Perceiving fingers in single-digit arithmetic problems.

PubMed

Berteletti, Ilaria; Booth, James R

2015-01-01

In this study, we investigate in children the neural underpinnings of finger representation and finger movement involved in single-digit arithmetic problems. Evidence suggests that finger representation and finger-based strategies play an important role in learning and understanding arithmetic. Because different operations rely on different networks, we compared activation for subtraction and multiplication problems in independently localized finger somatosensory and motor areas and tested whether activation was related to skill. Brain activations from children between 8 and 13 years of age revealed that only subtraction problems significantly activated finger motor areas, suggesting reliance on finger-based strategies. In addition, larger subtraction problems yielded greater somatosensory activation than smaller problems, suggesting a greater reliance on finger representation for larger numerical values. Interestingly, better performance in subtraction problems was associated with lower activation in the finger somatosensory area. Our results support the importance of fine-grained finger representation in arithmetical skill and are the first neurological evidence for a functional role of the somatosensory finger area in proficient arithmetical problem solving, in particular for those problems requiring quantity manipulation. From an educational perspective, these results encourage investigating whether different finger-based strategies facilitate arithmetical understanding and encourage educational practices aiming at integrating finger representation and finger-based strategies as a tool for instilling stronger numerical sense.

Perceiving fingers in single-digit arithmetic problems

PubMed Central

Berteletti, Ilaria; Booth, James R.

2015-01-01

In this study, we investigate in children the neural underpinnings of finger representation and finger movement involved in single-digit arithmetic problems. Evidence suggests that finger representation and finger-based strategies play an important role in learning and understanding arithmetic. Because different operations rely on different networks, we compared activation for subtraction and multiplication problems in independently localized finger somatosensory and motor areas and tested whether activation was related to skill. Brain activations from children between 8 and 13 years of age revealed that only subtraction problems significantly activated finger motor areas, suggesting reliance on finger-based strategies. In addition, larger subtraction problems yielded greater somatosensory activation than smaller problems, suggesting a greater reliance on finger representation for larger numerical values. Interestingly, better performance in subtraction problems was associated with lower activation in the finger somatosensory area. Our results support the importance of fine-grained finger representation in arithmetical skill and are the first neurological evidence for a functional role of the somatosensory finger area in proficient arithmetical problem solving, in particular for those problems requiring quantity manipulation. From an educational perspective, these results encourage investigating whether different finger-based strategies facilitate arithmetical understanding and encourage educational practices aiming at integrating finger representation and finger-based strategies as a tool for instilling stronger numerical sense. PMID:25852582

Activity patterns of extrinsic finger flexors and extensors during movements of instructed and non-instructed fingers.

PubMed

van Beek, Nathalie; Stegeman, Dick F; van den Noort, Josien C; H E J Veeger, DirkJan; Maas, Huub

2018-02-01

The fingers of the human hand cannot be controlled fully independently. This phenomenon may have a neurological as well as a mechanical basis. Despite previous studies, the neuromechanics of finger movements are not fully understood. The aims of this study were (1) to assess the activation and coactivation patterns of finger specific flexor and extensor muscle regions during instructed single finger flexion and (2) to determine the relationship between enslaved finger movements and respective finger muscle activation. In 9 healthy subjects (age 22-29), muscle activation was assessed during single finger flexion using a 90 surface electromyography electrode grid placed over the flexor digitorum superficialis (FDS) and the extensor digitorum (ED). We found (1) no significant differences in muscle activation timing between fingers, (2) considerable muscle activity in flexor and extensor regions associated with the non-instructed fingers and (3) no correlation between the muscle activations and corresponding movement of non-instructed fingers. A clear disparity was found between the movement pattern of the non-instructed fingers and the activity pattern of the corresponding muscle regions. This suggests that mechanical factors, such as intertendinous and myofascial connections, may also affect finger movement independency and need to be taken into consideration when studying finger movement. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stabilization of the total force in multi-finger pressing tasks studied with the ‘inverse piano’ technique

PubMed Central

Martin, J.R.; Budgeon, M.K.; Zatsiorsky, V.M.; Latash, M.L.

2010-01-01

When one finger changes its force, other fingers of the hand can show unintended force changes in the same direction (enslaving) and in the opposite direction (error compensation). We tested a hypothesis that externally imposed changes in finger force predominantly lead to error compensation effects in other fingers thus stabilizing the total force. A novel device, the “inverse piano”, was used to impose controlled displacements to one of the fingers over different magnitudes and at different rates. Subjects (n =10) pressed with four fingers at a constant force level and then one of the fingers was unexpectedly raised. The subjects were instructed not to interfere with possible changes in the finger forces. Raising a finger caused an increase in its force and a drop in the force of the other three fingers. Overall, total force showed a small increase. Larger force drops were seen in neighbors of the raised finger (proximity effect). The results show that multi-finger force stabilizing synergies dominate during involuntary reactions to externally imposed finger force changes. Within the referent configuration hypothesis, the data suggest that the instruction “not to interfere” leads to adjustments of the referent coordinates of all the individual fingers. PMID:21450360

Mallet finger - aftercare

MedlinePlus

Baseball finger - aftercare; Drop finger - aftercare; Avulsion fracture - mallet finger - aftercare ... away from the rest of the bone (avulsion fracture) Mallet finger most often occurs when something hits ...

Patterns of Dupuytren disease in fingers: studying correlations with a multivariate ordinal logit model.

PubMed

Lanting, Rosanne; Nooraee, Nazanin; Werker, Paul M N; van den Heuvel, Edwin R

2014-09-01

Dupuytren disease affects fingers in a variable fashion. Knowledge about specific disease patterns (phenotype) based on location and severity of the disease is lacking. In this cross-sectional study, 344 primary affected hands with Dupuytren disease were physically examined. The Pearson correlation coefficient between the coexistence of Dupuytren disease in pairs of fingers was calculated, and agglomerative hierarchical clustering was applied to identify possible clusters of affected fingers. With a multivariate ordinal logit model, the authors studied the correlation on severity, taking into account age and sex, and tested hypotheses on independence between groups of fingers. The ring finger was most frequently affected by Dupuytren disease, and contractures were seen in 15.1 percent of affected rays. The severity of thumb and index finger, middle and ring fingers, and middle and little fingers was significantly correlated. Occurrences in pairs of fingers were highest in the middle and ring fingers and lowest in the thumb and index finger. Correlation between the ring and little fingers and a correlation between fingers from the ulnar and radial sides could not be demonstrated. Rays on the ulnar side of the hand are predominantly affected. The middle finger is substantially correlated with other fingers on the ulnar side, and the thumb and index finger are correlated; however, there was no evidence that the ulnar side and the radial side were correlated in any way, which suggests that occurrence on one side of the hand does not predict Dupuytren disease on the other side of the hand. Risk, III.

Adaptive flexibility of the within-hand attentional gradient in touch: An MEG study.

PubMed

Kida, Tetsuo; Tanaka, Emi; Kakigi, Ryusuke

2018-06-21

Previous studies have demonstrated the cortical mechanisms for the gradient of spatial attention in vision and audition, whereas those for touch have yet to be elucidated in detail. In order to examine the within-hand gradient of tactile spatial attention in the cerebral cortex, we used magnetoencephalography (MEG) to record cortical responses to an electrocutaneous stimulation presented randomly to any of the five fingers of the right hand at a random interstimulus interval (750-1250 ms). Participants attended to the index finger, ring finger, or both to detect a rare target stimulus in a sequence of frequent standard stimuli presented to the attended finger(s) by silent counting. Neuromagnetic responses around the contralateral primary and secondary somatosensory cortices (SIc and SIIc) at 50-70 ms and 80-100 ms, respectively, for the stimulation of the index or ring finger were stronger when that finger was attended than when the distant finger was attended or at rest. The amplitude of the SIIc response was also intermediate when the index and ring fingers were simultaneously attended. The SIIc response to the task-irrelevant stimulation of the thumb or little finger increased when the index or ring finger was attended, respectively, suggesting an across-finger gradient of tactile attention. Simultaneous attention to the index and ring fingers decreased the SIIc response to the task-irrelevant stimulation of the intervening middle finger more than that with attention to either one of the two fingers. The earliest attentional sign was observed for the SI M40c response, with the amplitude increasing with the stimulation of the unattended finger. Furthermore, late responses in the temporo-parietal junction (TPJ) and prefrontal cortex (PFC) were stronger with the stimulation of the unattended finger than with that of the attended finger. Thus, the present study provides cortical evidence for the adaptive control of the within-hand, across-finger gradient of tactile attention that depends on whether attention is focused on a single finger or divided into non-adjacent different fingers. Copyright © 2018. Published by Elsevier Inc.

Finger wear detection for production line battery tester

DOEpatents

Depiante, Eduardo V.

1997-01-01

A method for detecting wear in a battery tester probe. The method includes providing a battery tester unit having at least one tester finger, generating a tester signal using the tester fingers and battery tester unit with the signal characteristic of the electrochemical condition of the battery and the tester finger, applying wavelet transformation to the tester signal including computing a mother wavelet to produce finger wear indicator signals, analyzing the signals to create a finger wear index, comparing the wear index for the tester finger with the index for a new tester finger and generating a tester finger signal change signal to indicate achieving a threshold wear change.

Efficacy and safety of collagenase clostridium histolyticum in the treatment of proximal interphalangeal joints in dupuytren contracture: combined analysis of 4 phase 3 clinical trials.

PubMed

Badalamente, Marie A; Hurst, Lawrence C; Benhaim, Prosper; Cohen, Brian M

2015-05-01

To examine the results of proximal interphalangeal (PIP) joint contractures from 4 phase 3 clinical trials of collagenase clostridium histolyticum (CCH) injection for Dupuytren contracture. Patients enrolled in Collagenase Option for Reduction of Dupuytren I/II and JOINT I/II with one or more PIP joint contractures (20° to 80°) received CCH 0.58 mg/0.20 mL or placebo (Collagenase Option for Reduction of Dupuytren I/II only) injected directly into a palpable cord. The percentage of PIP joints achieving clinical success (0° to 5° of full extension), clinical improvement (50% or more reduction in baseline contracture), and range of motion improvement at 30 days after the first and last CCH injections was assessed. The PIP joint contractures were classified into low (40° or less) and high (more than 40°) baseline severity. Adverse events were recorded. A total of 506 adults (mean age, 63 ± 10 y; 80% male) received 1,165 CCH injections in 644 PIP joint cords (mean, 1.6 injections/cord). Most patients (60%) received 1 injection, with 24%, 16%, and 1% receiving 2, 3, and 4 injections, respectively. Clinical success and clinical improvement occurred in 27% and 49% of PIP joints after one injection and in 34% and 58% after the last injection. Patients with lower baseline severity showed greater improvement and response was comparable between fingers, as were improvements in range of motion. Adverse events occurring in more than 10% of patients were peripheral edema (58%), contusion (38%), injection site hemorrhage (23%), injection site pain (21%), injection site swelling (16%), and tenderness (13%). This incidence was consistent with data reported in phase 3 trials. Two tendon ruptures occurred. No further ruptures occurred after a modified injection technique was adopted. Collagenase clostridium histolyticum was effective and well tolerated in the short term in patients with Dupuytren PIP joint contractures. Therapeutic II. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Scattering Removal for Finger-Vein Image Restoration

PubMed Central

Yang, Jinfeng; Zhang, Ben; Shi, Yihua

2012-01-01

Finger-vein recognition has received increased attention recently. However, the finger-vein images are always captured in poor quality. This certainly makes finger-vein feature representation unreliable, and further impairs the accuracy of finger-vein recognition. In this paper, we first give an analysis of the intrinsic factors causing finger-vein image degradation, and then propose a simple but effective image restoration method based on scattering removal. To give a proper description of finger-vein image degradation, a biological optical model (BOM) specific to finger-vein imaging is proposed according to the principle of light propagation in biological tissues. Based on BOM, the light scattering component is sensibly estimated and properly removed for finger-vein image restoration. Finally, experimental results demonstrate that the proposed method is powerful in enhancing the finger-vein image contrast and in improving the finger-vein image matching accuracy. PMID:22737028

Leptin - a link between obesity and osteoarthritis. applications for prevention and treatment.

PubMed

Vuolteenaho, Katriina; Koskinen, Anna; Moilanen, Eeva

2014-01-01

Osteoarthritis (OA) is the most common cause of musculoskeletal disability and pain in the world. The current drug treatment for OA is symptom relieving, and there is an urgent need for treatments that could retard, prevent or repair cartilage destruction in OA. Obesity is a major risk factor for OA. Traditionally, it has been thought to contribute to the development of OA by increasing the load on weight-bearing joints. However, this appears to be an over-simplification, because obesity is also linked to OA in the hand and finger joints. Recent studies have shown that adipocytokine leptin is a possible link between obesity and OA: Leptin levels in synovial fluid are increased in obese patients, leptin receptor (Ob-R) is expressed in cartilage, and leptin induces the production of matrix metalloproteinases (MMPs), pro-inflammatory mediators and nitric oxide (NO) in chondrocytes. Furthermore, according to the very recent findings, not only leptin levels in the joint but also leptin sensitivity in the cartilage are enhanced in obese OA patients. The findings supporting leptin as a causative link between obesity and OA offer leptin as a potential target to the development of disease-modifying drugs for osteoarthritis (DMOAD), especially for obese patients. © 2013 Nordic Pharmacological Society. Published by John Wiley & Sons Ltd.

Vascular changes of the hand in professional baseball players with emphasis on digital ischemia in catchers.

PubMed

Ginn, T Adam; Smith, Adam M; Snyder, Jon R; Koman, L Andrew; Smith, Beth P; Rushing, Julia

2005-07-01

Repetitive trauma to the hand is a concern for baseball players. The present study investigated the effects of repetitive trauma and the prevalence of microvascular pathological changes in the hands of minor league professional baseball players. In contrast to previous investigators, we documented the presence of abnormalities in younger, asymptomatic individuals. Thirty-six baseball players on active minor league rosters underwent a history and physical examination of both hands as well as additional specialized tests, including Doppler ultrasound, a timed Allen test, determination of digital brachial pressure indices, and ring sizing of fingers. Data were compared between gloved hands and throwing hands, hitters and nonhitters, and players at four different positions (catcher [nine subjects], outfielder [seven subjects], infielder [five subjects], and pitcher [fifteen subjects]). Digital brachial indices in the ring fingers of the gloved (p < 0.05) and throwing hands (p < 0.02) of catchers were significantly diminished compared with those in all other players. Doppler testing showed a significantly greater prevalence of abnormal flow in the ulnar artery at Guyon's canal when catchers were compared with other position players (p < 0.01). Doppler abnormalities were significantly more common in the gloved hand compared with the throwing hand (p < 0.05). Seven of nine catchers (and only catchers) were found to have index finger hypertrophy (average change, two ring sizes; p < 0.01); the hypertrophy occurred at the proximal phalanx and the proximal interphalangeal joint of the gloved hand. Catchers had a significantly higher prevalence of subjective hand symptoms (specifically, weakness in the gloved hand) compared with pitchers and infielders/outfielders (44% compared with 7% and 17%, respectively; p < 0.05). Microvascular changes are present in the hands of otherwise healthy professional baseball players in all positions, with a significantly higher prevalence in catchers, prior to the development of clinically important ischemia. Repetitive trauma resulting from the impact of the baseball also leads to digital hypertrophy in the index finger of the gloved hand of catchers. Gloves currently used by professional catchers do not adequately protect the hand from repetitive trauma.

Detection of rheumatoid arthritis using infrared imaging

NASA Astrophysics Data System (ADS)

Frize, Monique; Adéa, Cynthia; Payeur, Pierre; Di Primio, Gina; Karsh, Jacob; Ogungbemile, Abiola

2011-03-01

Rheumatoid arthritis (RA) is an inflammatory disease causing pain, swelling, stiffness, and loss of function in joints; it is difficult to diagnose in early stages. An early diagnosis and treatment can delay the onset of severe disability. Infrared (IR) imaging offers a potential approach to detect changes in degree of inflammation. In 18 normal subjects and 13 patients diagnosed with Rheumatoid Arthritis (RA), thermal images were collected from joints of hands, wrists, palms, and knees. Regions of interest (ROIs) were manually selected from all subjects and all parts imaged. For each subject, values were calculated from the temperature measurements: Mode/Max, Median/Max, Min/Max, Variance, Max-Min, (Mode-Mean), and Mean/Min. The data sets did not have a normal distribution, therefore non parametric tests (Kruskal-Wallis and Ranksum) were applied to assess if the data from the control group and the patient group were significantly different. Results indicate that: (i) thermal images can be detected on patients with the disease; (ii) the best joints to image are the metacarpophalangeal joints of the 2nd and 3rd fingers and the knees; the difference between the two groups was significant at the 0.05 level; (iii) the best calculations to differentiate between normal subjects and patients with RA are the Mode/Max, Variance, and Max-Min. We concluded that it is possible to reliably detect RA in patients using IR imaging. Future work will include a prospective study of normal subjects and patients that will compare IR results with Magnetic Resonance (MR) analysis.

Finger posture modulates structural body representations

PubMed Central

Tamè, Luigi; Dransfield, Elanah; Quettier, Thomas; Longo, Matthew R.

2017-01-01

Patients with lesions of the left posterior parietal cortex commonly fail in identifying their fingers, a condition known as finger agnosia, yet are relatively unimpaired in sensation and skilled action. Such dissociations have traditionally been interpreted as evidence that structural body representations (BSR), such as the body structural description, are distinct from sensorimotor representations, such as the body schema. We investigated whether performance on tasks commonly used to assess finger agnosia is modulated by changes in hand posture. We used the ‘in between’ test in which participants estimate the number of unstimulated fingers between two touched fingers or a localization task in which participants judge which two fingers were stimulated. Across blocks, the fingers were placed in three levels of splay. Judged finger numerosity was analysed, in Exp. 1 by direct report and in Exp. 2 as the actual number of fingers between the fingers named. In both experiments, judgments were greater when non-adjacent stimulated fingers were positioned far apart compared to when they were close together or touching, whereas judgements were unaltered when adjacent fingers were stimulated. This demonstrates that BSRs are not fixed, but are modulated by the real-time physical distances between body parts. PMID:28223685

Design and analysis of an underactuated anthropomorphic finger for upper limb prosthetics.

PubMed

Omarkulov, Nurdos; Telegenov, Kuat; Zeinullin, Maralbek; Begalinova, Ainur; Shintemirov, Almas

2015-01-01

This paper presents the design of a linkage based finger mechanism ensuring extended range of anthropomorphic gripping motions. The finger design is done using a path-point generation method based on geometrical dimensions and motion of a typical index human finger. Following the design description, and its kinematics analysis, the experimental evaluation of the finger gripping performance is presented using the finger 3D printed prototype. The finger underactuation is achieved by utilizing mechanical linkage system, consisting of two crossed four-bar linkage mechanisms. It is shown that the proposed finger design can be used to design a five-fingered anthropomorphic hand and has the potential for upper limb prostheses development.

Finger wear detection for production line battery tester

DOEpatents

Depiante, E.V.

1997-11-18

A method is described for detecting wear in a battery tester probe. The method includes providing a battery tester unit having at least one tester finger, generating a tester signal using the tester fingers and battery tester unit with the signal characteristic of the electrochemical condition of the battery and the tester finger, applying wavelet transformation to the tester signal including computing a mother wavelet to produce finger wear indicator signals, analyzing the signals to create a finger wear index, comparing the wear index for the tester finger with the index for a new tester finger and generating a tester finger signal change signal to indicate achieving a threshold wear change. 9 figs.

Differing Dynamics of Intrapersonal and Interpersonal Coordination: Two-finger and Four-Finger Tapping Experiments

PubMed Central

Kodama, Kentaro; Furuyama, Nobuhiro; Inamura, Tetsunari

2015-01-01

Finger-tapping experiments were conducted to examine whether the dynamics of intrapersonal and interpersonal coordination systems can be described equally by the Haken—Kelso—Bunz model, which describes inter-limb coordination dynamics. This article reports the results of finger-tapping experiments conducted in both systems. Two within-subject factors were investigated: the phase mode and the number of fingers. In the intrapersonal experiment (Experiment 1), the participants were asked to tap, paced by a gradually hastening auditory metronome, looking at their fingers moving, using the index finger in the two finger condition, or the index and middle finger in the four-finger condition. In the interpersonal experiment (Experiment 2), pairs of participants performed the task while each participant used the outside hand, tapping with the index finger in the two finger condition, or the index and middle finger in the four-finger condition. Some results did not agree with the HKB model predictions. First, from Experiment 1, no significant difference was observed in the movement stability between the in-phase and anti-phase modes in the two finger condition. Second, from Experiment 2, no significant difference was found in the movement stability between the in-phase and anti-phase mode in the four-finger condition. From these findings, different coordination dynamics were inferred between intrapersonal and interpersonal coordination systems against prediction from the previous studies. Results were discussed according to differences between intrapersonal and interpersonal coordination systems in the availability of perceptual information and the complexity in the interaction between limbs derived from a nested structure. PMID:26070119

Transfer of tactile perceptual learning to untrained neighboring fingers reflects natural use relationships

PubMed Central

Harrar, Vanessa; Oliver, Jonathan; Johansen-Berg, Heidi; Spence, Charles

2015-01-01

Tactile learning transfers from trained to untrained fingers in a pattern that reflects overlap between the representations of fingers in the somatosensory system (e.g., neurons with multifinger receptive fields). While physical proximity on the body is known to determine the topography of somatosensory representations, tactile coactivation is also an established organizing principle of somatosensory topography. In this study we investigated whether tactile coactivation, induced by habitual inter-finger cooperative use (use pattern), shapes inter-finger overlap. To this end, we used psychophysics to compare the transfer of tactile learning from the middle finger to its adjacent fingers. This allowed us to compare transfer to two fingers that are both physically and cortically adjacent to the middle finger but have differing use patterns. Specifically, the middle finger is used more frequently with the ring than with the index finger. We predicted this should lead to greater representational overlap between the former than the latter pair. Furthermore, this difference in overlap should be reflected in differential learning transfer from the middle to index vs. ring fingers. Subsequently, we predicted temporary learning-related changes in the middle finger's representation (e.g., cortical magnification) would cause transient interference in perceptual thresholds of the ring, but not the index, finger. Supporting this, longitudinal analysis revealed a divergence where learning transfer was fast to the index finger but relatively delayed to the ring finger. Our results support the theory that tactile coactivation patterns between digits affect their topographic relationships. Our findings emphasize how action shapes perception and somatosensory organization. PMID:26631145

Transfer of tactile perceptual learning to untrained neighboring fingers reflects natural use relationships.

PubMed

Dempsey-Jones, Harriet; Harrar, Vanessa; Oliver, Jonathan; Johansen-Berg, Heidi; Spence, Charles; Makin, Tamar R

2016-03-01

Tactile learning transfers from trained to untrained fingers in a pattern that reflects overlap between the representations of fingers in the somatosensory system (e.g., neurons with multifinger receptive fields). While physical proximity on the body is known to determine the topography of somatosensory representations, tactile coactivation is also an established organizing principle of somatosensory topography. In this study we investigated whether tactile coactivation, induced by habitual inter-finger cooperative use (use pattern), shapes inter-finger overlap. To this end, we used psychophysics to compare the transfer of tactile learning from the middle finger to its adjacent fingers. This allowed us to compare transfer to two fingers that are both physically and cortically adjacent to the middle finger but have differing use patterns. Specifically, the middle finger is used more frequently with the ring than with the index finger. We predicted this should lead to greater representational overlap between the former than the latter pair. Furthermore, this difference in overlap should be reflected in differential learning transfer from the middle to index vs. ring fingers. Subsequently, we predicted temporary learning-related changes in the middle finger's representation (e.g., cortical magnification) would cause transient interference in perceptual thresholds of the ring, but not the index, finger. Supporting this, longitudinal analysis revealed a divergence where learning transfer was fast to the index finger but relatively delayed to the ring finger. Our results support the theory that tactile coactivation patterns between digits affect their topographic relationships. Our findings emphasize how action shapes perception and somatosensory organization. Copyright © 2016 the American Physiological Society.

Impact of Finger Type in Fingerprint Authentication

NASA Astrophysics Data System (ADS)

Gafurov, Davrondzhon; Bours, Patrick; Yang, Bian; Busch, Christoph

Nowadays fingerprint verification system is the most widespread and accepted biometric technology that explores various features of the human fingers for this purpose. In general, every normal person has 10 fingers with different size. Although it is claimed that recognition performance with little fingers can be less accurate compared to other finger types, to our best knowledge, this has not been investigated yet. This paper presents our study on the topic of influence of the finger type into fingerprint recognition performance. For analysis we employ two fingerprint verification software packages (one public and one commercial). We conduct test on GUC100 multi sensor fingerprint database which contains fingerprint images of all 10 fingers from 100 subjects. Our analysis indeed confirms that performance with small fingers is less accurate than performance with the others fingers of the hand. It also appears that best performance is being obtained with thumb or index fingers. For example, performance deterioration from the best finger (i.e. index or thumb) to the worst fingers (i.e. small ones) can be in the range of 184%-1352%.

Validation of automatic joint space width measurements in hand radiographs in rheumatoid arthritis.

PubMed

Schenk, Olga; Huo, Yinghe; Vincken, Koen L; van de Laar, Mart A; Kuper, Ina H H; Slump, Kees C H; Lafeber, Floris P J G; Bernelot Moens, Hein J

2016-10-01

Computerized methods promise quick, objective, and sensitive tools to quantify progression of radiological damage in rheumatoid arthritis (RA). Measurement of joint space width (JSW) in finger and wrist joints with these systems performed comparable to the Sharp-van der Heijde score (SHS). A next step toward clinical use, validation of precision and accuracy in hand joints with minimal damage, is described with a close scrutiny of sources of error. A recently developed system to measure metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints was validated in consecutive hand images of RA patients. To assess the impact of image acquisition, measurements on radiographs from a multicenter trial and from a recent prospective cohort in a single hospital were compared. Precision of the system was tested by comparing the joint space in mm in pairs of subsequent images with a short interval without progression of SHS. In case of incorrect measurements, the source of error was analyzed with a review by human experts. Accuracy was assessed by comparison with reported measurements with other systems. In the two series of radiographs, the system could automatically locate and measure 1003/1088 (92.2%) and 1143/1200 (95.3%) individual joints, respectively. In joints with a normal SHS, the average (SD) size of MCP joints was [Formula: see text] and [Formula: see text] in the two series of radiographs, and of PIP joints [Formula: see text] and [Formula: see text]. The difference in JSW between two serial radiographs with an interval of 6 to 12 months and unchanged SHS was [Formula: see text], indicating very good precision. Errors occurred more often in radiographs from the multicenter cohort than in a more recent series from a single hospital. Detailed analysis of the 55/1125 (4.9%) measurements that had a discrepant paired measurement revealed that variation in the process of image acquisition (exposure in 15% and repositioning in 57%) was a more frequent source of error than incorrect delineation by the software (25%). Various steps in the validation of an automated measurement system for JSW of MCP and PIP joints are described. The use of serial radiographs from different sources, with a short interval and limited damage, is helpful to detect sources of error. Image acquisition, in particular repositioning, is a dominant source of error.

Comparison of seronegative and seropositive rheumatoid arthritis with regard to some clinical characteristics.

PubMed

Sahatçiu-Meka, Vjollca; Izairi, Remzi; Rexhepi, Sylejman; Manxhuka-Kerliu, Suzana

2009-01-01

The aim of this study is to establish a scientific comparative analysis between seronegative and seropositive rheumatoid arthritis (RA), with regard to some clinical characteristics. The studied group consisted of RA seronegative patients with titters lower then 1:64 defined by Rose-Waaler test, while the control group consisted of RA seropositive patients with titters of 1:64 or higher. Examinees all belonged to the 2nd and 3rd functional classes according to ARA criteria, were between 25-60 years of age (Xb = 49.96), with disease duration between 1-27 years (Xbox = 6.41). In the disease onset most frequently affected joints were metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joint of the hands, almost equally represented with regard to sero-status and sex. During the examination seropositive patients showed a higher presence of inflamation of peripheral joints of hand and foot, but only the presence of PIP of the hands was statistically significant (chi2 = 15.63, p < 0.01). Knees, talocrural joints and elbows were more frequently affected in seropositive patients, whereas humeroscapular, coxofemoral and sacroiliacal joints were more frequently affected in seronegative patients, but without significant statistical difference with regard to sero-status. The presence of affected PIP of the hands (chi2 = 9.96, p < 0.01) and knees (chi2 = 4.17, p < 0.05) with regard to sex was statistically significant in seropositive female patients, as well as the presence of atacked PIP of the hands (chi2 = 6.08, p < 0.05), and cervical vertebrae (chi2 = 6.00, p < 0.05) in seropositive male patients. There were some differences between groups with regard to sex in metatarsophalangealjoints (MTP), PIP of the foot, and other joints, but without any statistical significance. In both subsets statistically significant domination was found in affected second (chi2 = 20.85, p < 0.01) and third (chi2 = 15.70, p < 0.01) fingers of the PIP level of hands and third finger (chi2 = 6.52, p < 0.05) of the MCP level. The mentioned parameters did not show a significant statistical difference with regard to sero-status and sex. Majority of patients had 1-4 deformities. Seropositive group had prevalent knee contractures, e.g. the eversion of the foot, while seronegative group had more "swan neck" deformities. The mentioned parameters did not show a significant statistical difference with regard to sero-status and sex. Longer duration of the disease resulted in an increased number of deformities, and this difference was statistically significant (t = 5.92, p < 0.01). Linear correlation between these two parameters resulted as high positive in general (r = 0.49, p < 0.01) and for groups separately, but without significant statistical difference with regard to sero-status. Duration of the disease with regard to the type of deformities was different in both subsets: in case of the longer duration of the disease "buttonhole" was prevalent with statistically significant difference in seropositive patients (t = 2.10, p < 0.05), whereas "fibular deviation" was prevalent in seronegative patients (t = 2.64, p < 0.01).

Integrated circuit package with lead structure and method of preparing the same

NASA Technical Reports Server (NTRS)

Kennedy, B. W. (Inventor)

1973-01-01

A beam-lead integrated circuit package assembly including a beam-lead integrated circuit chip, a lead frame array bonded to projecting fingers of the chip, a rubber potting compound disposed around the chip, and an encapsulating molded plastic is described. The lead frame array is prepared by photographically printing a lead pattern on a base metal sheet, selectively etching to remove metal between leads, and plating with gold. Joining of the chip to the lead frame array is carried out by thermocompression bonding of mating goldplated surfaces. A small amount of silicone rubber is then applied to cover the chip and bonded joints, and the package is encapsulated with epoxy resin, applied by molding.

Force Model for Control of Tendon Driven Hands

NASA Technical Reports Server (NTRS)

Pena, Edward; Thompson, David E.

1997-01-01

Knowing the tendon forces generated for a given task such as grasping via a model, an artificial hand can be controlled. A two-dimensional force model for the index finger was developed. This system is assumed to be in static equilibrium, therefore, the equations of equilibrium were applied at each joint. Constraint equations describing the tendon branch connectivity were used. Gaussian elimination was used to solve for the unknowns of the Linear system. Results from initial work on estimating tendon forces in post-operative hands during active motion therapy were discussed. The results are important for understanding the effects of hand position on tendon tension, elastic effects on tendon tension, and overall functional anatomy of the hand.

Familial multiple ventricular extrasystoles, short stature, craniofacial abnormalities and digital hypoplasia: a further case of Stoll syndrome?

PubMed

Mercer, Catherine L; Keeton, Barry; Dennis, Nicolas R

2008-04-01

We report two brothers, their mother and a maternal cousin who had a distinctive facial phenotype, mild brachydactyly and prominence of the interphalangeal joints. One brother and the mother also had multiple ventricular extrasystoles. Six other relatives in four generations were probably affected on the basis of history and family photographs. We also report a further individual from a different family with a similar facial phenotype, Pierre-Robin sequence, tapering fingers and multiple ventricular extrasystoles. These families have some similarities to those reported by Stoll et al. in a single family, showing dominant inheritance. Our patients would seem to have the same or a related condition.

Intensity Variation Normalization for Finger Vein Recognition Using Guided Filter Based Singe Scale Retinex

PubMed Central

Xie, Shan Juan; Lu, Yu; Yoon, Sook; Yang, Jucheng; Park, Dong Sun

2015-01-01

Finger vein recognition has been considered one of the most promising biometrics for personal authentication. However, the capacities and percentages of finger tissues (e.g., bone, muscle, ligament, water, fat, etc.) vary person by person. This usually causes poor quality of finger vein images, therefore degrading the performance of finger vein recognition systems (FVRSs). In this paper, the intrinsic factors of finger tissue causing poor quality of finger vein images are analyzed, and an intensity variation (IV) normalization method using guided filter based single scale retinex (GFSSR) is proposed for finger vein image enhancement. The experimental results on two public datasets demonstrate the effectiveness of the proposed method in enhancing the image quality and finger vein recognition accuracy. PMID:26184226

Intensity Variation Normalization for Finger Vein Recognition Using Guided Filter Based Singe Scale Retinex.

PubMed

Xie, Shan Juan; Lu, Yu; Yoon, Sook; Yang, Jucheng; Park, Dong Sun

2015-07-14

Finger vein recognition has been considered one of the most promising biometrics for personal authentication. However, the capacities and percentages of finger tissues (e.g., bone, muscle, ligament, water, fat, etc.) vary person by person. This usually causes poor quality of finger vein images, therefore degrading the performance of finger vein recognition systems (FVRSs). In this paper, the intrinsic factors of finger tissue causing poor quality of finger vein images are analyzed, and an intensity variation (IV) normalization method using guided filter based single scale retinex (GFSSR) is proposed for finger vein image enhancement. The experimental results on two public datasets demonstrate the effectiveness of the proposed method in enhancing the image quality and finger vein recognition accuracy.

Zinc finger proteins in cancer progression.

PubMed

Jen, Jayu; Wang, Yi-Ching

2016-07-13

Zinc finger proteins are the largest transcription factor family in human genome. The diverse combinations and functions of zinc finger motifs make zinc finger proteins versatile in biological processes, including development, differentiation, metabolism and autophagy. Over the last few decades, increasing evidence reveals the potential roles of zinc finger proteins in cancer progression. However, the underlying mechanisms of zinc finger proteins in cancer progression vary in different cancer types and even in the same cancer type under different types of stress. Here, we discuss general mechanisms of zinc finger proteins in transcription regulation and summarize recent studies on zinc finger proteins in cancer progression. In this review, we also emphasize the importance of further investigations in elucidating the underlying mechanisms of zinc finger proteins in cancer progression.

EMG finger movement classification based on ANFIS

NASA Astrophysics Data System (ADS)

Caesarendra, W.; Tjahjowidodo, T.; Nico, Y.; Wahyudati, S.; Nurhasanah, L.

2018-04-01

An increase number of people suffering from stroke has impact to the rapid development of finger hand exoskeleton to enable an automatic physical therapy. Prior to the development of finger exoskeleton, a research topic yet important i.e. machine learning of finger gestures classification is conducted. This paper presents a study on EMG signal classification of 5 finger gestures as a preliminary study toward the finger exoskeleton design and development in Indonesia. The EMG signals of 5 finger gestures were acquired using Myo EMG sensor. The EMG signal features were extracted and reduced using PCA. The ANFIS based learning is used to classify reduced features of 5 finger gestures. The result shows that the classification of finger gestures is less than the classification of 7 hand gestures.

Real time relationship between individual finger force and grip exertion on distal phalanges in linear force following tasks.

PubMed

Luo, Shi-Jian; Shu, Ge; Gong, Yan

2018-05-01

Individual finger force (FF) in a grip task is a vital concern in rehabilitation engineering and precise control of manipulators because disorders in any of the fingers will affect the stability or accuracy of the grip force (GF). To understand the functions of each finger in a dynamic grip exertion task, a GF following experiment with four individual fingers without thumb was designed. This study obtained four individual FFs from the distal phalanges with a cylindrical handle in dynamic GF following tasks. Ten healthy male subjects with similar hand sizes participated in the four-finger linear GF following tasks at different submaximal voluntary contraction (SMVC) levels. The total GF, individual FF, finger force contribution, and following error were subsequently calculated and analyzed. The statistics indicated the following: 1) the accuracy and stability of GF at low %MVC were significantly higher than those at high SMVC; 2) at low SMVC, the ability of the fingers to increase the GF was better than the ability to reduce it, but it was contrary at high SMVC; 3) when the target wave (TW) was changing, all four fingers strongly participated in the force exertion, but the participation of the little finger decreased significantly when TW remained stable; 4) the index finger and ring finger had a complementary relationship and played a vital role in the adjustment and control of GF. The middle finger and little finger had a minor influence on the force control and adjustment. In conclusion, each of the fingers had different functions in a GF following task. These findings can be used in the assessment of finger injury rehabilitation and for algorithms of precise control. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preliminary Test Results of a Non-Contacting Finger Seal on a Herringbone-Grooved Rotor

NASA Technical Reports Server (NTRS)

Proctor, Margaret P.; Delgado, Irebert R.

2009-01-01

The baseline non-contacting finger seal is a NASA patented design. The primary difference between it and Gul Aroras design patented by AlliedSignal is that there are no lift pads on the high pressure fingers. The baseline non-contacting finger seal is comprised of a back plate, aft spacer, aft (or low pressure) finger element, forward (or high pressure) finger element, forward spacer, and front plate. The components are held together with 20 flat head screws. A typical seal would have a back plate of approximately the same thickness as the front plate and would be riveted together. The thicker back plate allows use of threaded fasteners so that different finger elements can be tested without having to replace all the individual seal components. The finger elements are essentially washers made of thin sheet stock with multiple curved slots machined around the inner diameter to form the fingers. They are clocked so that the fingers of one cover the slots of the other. The aft finger element fingers have axial extensions or "lift pads" at the seal id that are concentric to the rotor. The fingers act as cantilever beams and flex in response to rotor dynamic motion and radial growth of the rotor due to centrifugal or thermal forces.

Efficacy and safety of collagenase Clostridium histolyticum injection for Dupuytren contracture: report of 40 cases.

PubMed

Alberton, F; Corain, M; Garofano, A; Pangallo, L; Valore, A; Zanella, V; Adani, R

2014-12-01

Dupuytren's disease (DD) is a fibroproliferative pathology that affects the palmar aponeurosis causing the development of nodules and collagen cords and the progressive flexion of the fingers. The standard procedure is surgical fasciectomy, followed by high recurrence rates. Collagenase Clostridium histolyticum (CCH) injection represents an innovative noninvasive approach to the treatment of DD. This prospective study was designed to examine the efficacy and safety of CCH injection performed in the outpatient, using local anesthesia. Forty patients [32 metacarpophalangeal (MP), 8 proximal interphalangeal (PIP)] with Dupuytren's contracture of at least 20° for MP joint and any degree for PIP joint were included. The mean age was 66. All joints were treated with a single vial of collagenase injection and manual breaking of the cord 24 h after. All adverse effects (AEs) were monitored. Patients were checked 7, 30, 90, and 180 days after the injection. Primary endpoint was a reduction in digit contracture within 0°-5° of normal extension. Secondary endpoints were the improvement of range of motion, the evaluation of AEs incidence, and cost-effectiveness of collagenase treatment. About 67.5 % of patients obtained a clinical success. At 6 months, a further 7.5% attained the same result. The mean contracture of treated joints was 5.3º for MP and 6.8° for PIP joints. Twenty-three patients had one or more mild-to-moderate side effects. The use of collagenase appears to be an effective and safe method for the treatment of Dupuytren's contracture. Therapeutic success was achieved in a significant percentage of patients. The incidence of side effects was higher, but they were local reactions of short duration. The use of a single collagenase vial in patients treated in day surgery appears more cost-effective than surgery.

Distinct neural control of intrinsic and extrinsic muscles of the hand during single finger pressing.

PubMed

Dupan, Sigrid S G; Stegeman, Dick F; Maas, Huub

2018-06-01

Single finger force tasks lead to unintended activation of the non-instructed fingers, commonly referred to as enslaving. Both neural and mechanical factors have been associated with this absence of finger individuality. This study investigates the amplitude modulation of both intrinsic and extrinsic finger muscles during single finger isometric force tasks. Twelve participants performed single finger flexion presses at 20% of maximum voluntary contraction, while simultaneously the electromyographic activity of several intrinsic and extrinsic muscles associated with all four fingers was recorded using 8 electrode pairs in the hand and two 30-electrode grids on the lower arm. The forces exerted by each of the fingers, in both flexion and extension direction, were recorded with individual force sensors. This study shows distinct activation patterns in intrinsic and extrinsic hand muscles. Intrinsic muscles exhibited individuation, where the agonistic and antagonistic muscles associated with the instructed fingers showed the highest activation. This activation in both agonistic and antagonistic muscles appears to facilitate finger stabilisation during the isometric force task. Extrinsic muscles show an activation independent from instructed finger in both agonistic and antagonistic muscles, which appears to be associated with stabilisation of the wrist, with an additional finger-dependent modulation only present in the agonistic extrinsic muscles. These results indicate distinct muscle patterns in intrinsic and extrinsic hand muscles during single finger isometric force pressing. We conclude that the finger specific activation of intrinsic muscles is not sufficient to fully counteract enslaving caused by the broad activation of the extrinsic muscles. Copyright © 2018 Elsevier B.V. All rights reserved.

Robotic hand and fingers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salisbury, Curt Michael; Dullea, Kevin J.

Technologies pertaining to a robotic hand are described herein. The robotic hand includes one or more fingers releasably attached to a robotic hand frame. The fingers can abduct and adduct as well as flex and tense. The fingers are releasably attached to the frame by magnets that allow for the fingers to detach from the frame when excess force is applied to the fingers.

New Finger Biometric Method Using Near Infrared Imaging

PubMed Central

Lee, Eui Chul; Jung, Hyunwoo; Kim, Daeyeoul

2011-01-01

In this paper, we propose a new finger biometric method. Infrared finger images are first captured, and then feature extraction is performed using a modified Gaussian high-pass filter through binarization, local binary pattern (LBP), and local derivative pattern (LDP) methods. Infrared finger images include the multimodal features of finger veins and finger geometries. Instead of extracting each feature using different methods, the modified Gaussian high-pass filter is fully convolved. Therefore, the extracted binary patterns of finger images include the multimodal features of veins and finger geometries. Experimental results show that the proposed method has an error rate of 0.13%. PMID:22163741

An EMG-CT method using multiple surface electrodes in the forearm.

PubMed

Nakajima, Yasuhiro; Keeratihattayakorn, Saran; Yoshinari, Satoshi; Tadano, Shigeru

2014-12-01

Electromyography computed tomography (EMG-CT) method is proposed for visualizing the individual muscle activities in the human forearm. An EMG conduction model was formulated for reverse-estimation of muscle activities using EMG signals obtained with multi surface electrodes. The optimization process was calculated using sequential quadratic programming by comparing the estimated EMG values from the model with the measured values. The individual muscle activities in the deep region were estimated and used to produce an EMG tomographic image. For validation of the method, isometric contractions of finger muscles were examined for three subjects, applying a flexion load (4.9, 7.4 and 9.8 N) to the proximal interphalangeal joint of the middle finger. EMG signals in the forearm were recorded during the tasks using multiple surface electrodes, which were bound around the subject's forearm. The EMG-CT method illustrates the distribution of muscle activities within the forearm. The change in amplitude and area of activated muscles can be observed. The normalized muscle activities of all three subjects appear to increase monotonically with increases in the load. Kinesiologically, this method was able to estimate individual muscle activation values and could provide a novel tool for studying hand function and development of an examination for evaluating rehabilitation. Copyright © 2014 Elsevier Ltd. All rights reserved.

JOVE Pilot Research Study in Astronomy and Microgravity Sciences

NASA Technical Reports Server (NTRS)

Strauss, Alvin M.; Hmelo, Anthony; Peterson, Steven

1996-01-01

The purpose of this project was to develop hardware and software facilities for evaluating the biomechanical interactions between human hands and space suit gloves. The first task was to measure finger joint angles inside space suit gloves. A preliminary survey identified three potential systems which could be used in the proposed study. In response to the current market situation, a glove for measuring the positions of the hand inside a space suit has been developed. A prototype of the glove has been constructed to demonstrate its sensing technologies. There are two types of sensors in the glove. The positions of the fingers are measured using bend sensors based on the CyberGlove design. This sensor consists of two strain gages mounted to a 0.003 inch thick mylar sheet. The sensor is encapsulated using 0.001 inch kapton film to give it sufficient rigidity. Along gage is used to average the strain generated in the sensor due to bending This average strain produces an output signal proportional to the angle of the bend. The force sensor consists of conductive ink sandwiched between two plastic sheets. An electrode is printed on one of the plastic sheets using silver ink. The resistance of the ink is sensitive to pressure.

Arthrodesis of the proximal interphalangeal joint of the 4th and 5th finger using an interlocking screw device to treat severe recurrence of Dupuytren's disease.

PubMed

Novoa-Parra, C D; Montaner-Alonso, D; Pérez-Correa, J I; Morales-Rodríguez, J; Rodrigo-Pérez, J L; Morales-Suarez-Varela, M

To assess the radiological and functional outcome of arthrodesis of the 4th and 5th finger using the APEX™ (Extremity Medical, Parsippany,NJ)intermedullary interlocking screw system in patients with severe recurrence of Dupuytren's disease. The DASH questionnaire and the VAS scale were used to assess the clinical outcomes. The angle of arthrodesis, fusion time and implant fixation were evaluated on x-rays. The patients were monitored for complications during surgery and the follow-up period. The sample comprised 6 patients. Mean follow up was 19.6 months. All of the patients presented clinical and radiological evidence of fusion at 8 weeks, with fusion angles of 30° (3) and 45° (3). There were no complications and none of the implants had to be removed. The functional outcomes in these patients were poor. The system offers a reliable method for IPJ arthrodesis at a precise angle. It promotes stable fixation that does not require prolonged immobilisation. It can be used together with other procedures on the hand with severe recurrence of DD. The functional outcomes for this group of patients using this device were poor. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Musculoskeletal disorders in professional violinists and violists. Systematic review.

PubMed

Moraes, Geraldo Fabiano de Souza; Antunes, Adriana Papini

2012-01-01

Due to the high physical and psychological demands of their work, musicians have a high risk of developing a range of health problems. The main causes of musculoskeletal disorders seen in instrumentalists are overuse, nerve compression and focal dystonia. The aim of this paper is to identify the musculoskeletal disorders that most frequently affect professional violinists and violists. 50 articles were read, of which 24 were used. The PEDro scale was used to determine the quality of the articles. The definition of risk factors can help in the development of prevention programs. Playing a musical instrument involves a combination of actions, including rapid, repetitive and complicated movements of the hands and fingers. The chairs used offer no other option than to adapt to the demands of body posture. To achieve the necessary skills to become a musician of a high standard, many hours of training and perfection are required. The neck, shoulder and temporomandibular joints are the most commonly affected areas, due to prolonged flexion of the head and shoulder required to hold the violin. The elbow and fingers are also common sites of disorders. It is necessary to warn musicians of the initial symptoms, and how they can prevent the disorder from worsening. Level I Evidence (Centre for Evidence-Based Medicine, Oxford, UK).

Robot-Assisted Guitar Hero for Finger Rehabilitation after Stroke

PubMed Central

Taheri, Hossein; Rowe, Justin B.; Gardner, David; Chan, Vicky; Reinkensmeyer, David J.; Wolbrecht, Eric T.

2014-01-01

This paper describes the design and testing of a robotic device for finger therapy after stroke: FINGER (Finger Individuating Grasp Exercise Robot). FINGER makes use of stacked single degree-of-freedom mechanisms to assist subjects in moving individual fingers in a naturalistic grasping pattern through much of their full range of motion. The device has a high bandwidth of control (−3dB at approximately 8 Hz) and is backdriveable. These characteristics make it capable of assisting in grasping tasks that require precise timing. We therefore used FINGER to assist individuals with a stroke (n = 8) and without impairment (n = 4) in playing a game similar to Guitar Hero©. The subjects attempted to move their fingers to target positions at times specified by notes that were graphically streamed to popular music. We show here that by automatically adjusting the robot gains, it is possible to use FINGER to modulate the subject’s success rate at the game, across a range of impairment levels. Modulating success rates did not alter the stroke subject’s effort, although the unimpaired subjects exerted more force when they were made less successful. We also present a novel measure of finger individuation that can be assessed as individuals play Guitar Hero with FINGER. The results demonstrate the ability of FINGER to provide controlled levels of assistance during an engaging computer game, and to quantify finger individuation after stroke. PMID:23366783

Radiation safety education reduces the incidence of adult fingers on neonatal chest radiographs.

PubMed

Sahota, N; Burbridge, B E; Duncan, M D

2014-06-01

A previous audit revealed a high frequency of adult fingers visualised on neonatal intensive care unit (NICU) chest radiographs-representing an example of inappropriate occupational radiation exposure. Radiation safety education was provided to staff and we hypothesised that the education would reduce the frequency of adult fingers visualised on NICU chest radiographs. Two cross-sectional samples taken before and after the administration of the education were compared. We examined fingers visualised directly in the beam, fingers in the direct beam but eliminated by technologists editing the image, and fingers under the cones of the portable x-ray machine. There was a 46.2% reduction in fingers directly in the beam, 50.0% reduction in fingers directly in the beam but cropped out, and 68.4% reduction in fingers in the coned area. There was a 57.1% overall reduction in adult fingers visualised, which was statistically significant (Z value - 7.48, P < 0.0001). This study supports radiation safety education in minimising inappropriate occupational radiation exposure.

Tendon Driven Finger Actuation System

NASA Technical Reports Server (NTRS)

Ihrke, Chris A. (Inventor); Reich, David M. (Inventor); Bridgwater, Lyndon (Inventor); Linn, Douglas Martin (Inventor); Askew, Scott R. (Inventor); Diftler, Myron A. (Inventor); Platt, Robert (Inventor); Hargrave, Brian (Inventor); Valvo, Michael C. (Inventor); Abdallah, Muhammad E. (Inventor);

Forgotten but Not Gone! Syphilis Induced Tenosynovitis.

PubMed

Ratnaraj, Felicia; Brooks, David; Walton, Mollie; Nagabandi, Arun; Abu Hazeem, Mahmoud

2016-01-01

Objective . Tenosynovitis, inflammation of a tendon and its synovial sheath, is a rare manifestation of secondary syphilis and if diagnosed early is reversible. Background . A 52-year-old male with past medical history of untreated syphilis presented with gradual onset of swelling and pain of the right fourth metacarpophalangeal joint (MCP). He reported a history of painless penile lesions after having sexual intercourse with a new partner approximately five months ago which was treated with sulfamethoxazole/trimethoprim. An RPR done at that time came back positive with a high titer; however, patient was lost to follow-up. On examination, patient had an edematous, nonerythematous right fourth proximal interphalangeal (PIP) joint. Urgent irrigation, debridement, and exploration of the right hand into the tendon sheath were performed. With his history of syphillis, an RPR was done, which was reactive with a titer of 1 : 64. A confirmatory FTA-ABS test was completed, rendering a positive result. Based on his history of untreated syphilis, dormancy followed by clinical scenario of swelling of the right fourth finger, and a high RPR titer, he was diagnosed with secondary syphilis manifesting as tenosynovitis.

Forgotten but Not Gone! Syphilis Induced Tenosynovitis

PubMed Central

Brooks, David; Walton, Mollie; Nagabandi, Arun

2016-01-01

Objective. Tenosynovitis, inflammation of a tendon and its synovial sheath, is a rare manifestation of secondary syphilis and if diagnosed early is reversible. Background. A 52-year-old male with past medical history of untreated syphilis presented with gradual onset of swelling and pain of the right fourth metacarpophalangeal joint (MCP). He reported a history of painless penile lesions after having sexual intercourse with a new partner approximately five months ago which was treated with sulfamethoxazole/trimethoprim. An RPR done at that time came back positive with a high titer; however, patient was lost to follow-up. On examination, patient had an edematous, nonerythematous right fourth proximal interphalangeal (PIP) joint. Urgent irrigation, debridement, and exploration of the right hand into the tendon sheath were performed. With his history of syphillis, an RPR was done, which was reactive with a titer of 1 : 64. A confirmatory FTA-ABS test was completed, rendering a positive result. Based on his history of untreated syphilis, dormancy followed by clinical scenario of swelling of the right fourth finger, and a high RPR titer, he was diagnosed with secondary syphilis manifesting as tenosynovitis. PMID:28050292

Sports-related pads.

PubMed

Dickens, Rio; Adams, Brian B; Mutasim, Diya F

2002-05-01

Knuckle pads, first described by Garrod in 1893, 1 are benign, asymptomatic, well- circumscribed, smooth, firm, skin colored papules, nodules, or plaques. They most commonly occur on the dorsal aspect of the proximal interphalangeal joint of the finger, 2 but also may occur on the dorsal aspects of the foot over joints. 3-5 Knuckle pads may be inherited or acquired. 1 While some authors suggest that trauma is not a significant factor, 6 acquired knuckle pads have been associated with repetitive friction and trauma, 2,7 and may resemble athlete's nodules (also referred to as collagenomas). 1 Histologically, knuckle pads are characterized by hyperkeratosis, hypergranulosis, proliferation of fibroblasts and capillaries, and thickened and irregular collagen bundles. 1 Few cases of knuckle pads involving the lower extremities have been reported. 7 Knuckle pads of the feet have been described in association with inherited syndromes, such as acrokeratoelastoidosis Costa, 3 a syndrome of knuckle pads, leukonychia and deafness, 4 and a syndrome of knuckle pads, leukonychia, deafness and keratosis palmoplantaris. 5 We report a case that illustrates an unusual presentation of acquired knuckle pads of the feet secondary to repetitive friction from athletic gear.

Force-Time Entropy of Isometric Impulse.

PubMed

Hsieh, Tsung-Yu; Newell, Karl M

2016-01-01

The relation between force and temporal variability in discrete impulse production has been viewed as independent (R. A. Schmidt, H. Zelaznik, B. Hawkins, J. S. Frank, & J. T. Quinn, 1979 ) or dependent on the rate of force (L. G. Carlton & K. M. Newell, 1993 ). Two experiments in an isometric single finger force task investigated the joint force-time entropy with (a) fixed time to peak force and different percentages of force level and (b) fixed percentage of force level and different times to peak force. The results showed that the peak force variability increased either with the increment of force level or through a shorter time to peak force that also reduced timing error variability. The peak force entropy and entropy of time to peak force increased on the respective dimension as the parameter conditions approached either maximum force or a minimum rate of force production. The findings show that force error and timing error are dependent but complementary when considered in the same framework with the joint force-time entropy at a minimum in the middle parameter range of discrete impulse.

Work-Related Upper Limb Disorders: A Case Report

PubMed Central

Stoyneva, Zlatka Borisova; Dermendjiev, Svetlan; Dermendjiev, Tihomir; Dobrev, Hristo

2015-01-01

In this study the complex interrelationship between physical factors, job stress, lifestyle and genetic factors on symptoms of work-related musculoskeletal disorders of the upper limbs is demonstrated by a case report and discussion of the literature. A 58 year old woman with long lasting complaints of the upper limbs with increasing intensity and duration, generalisation, combined with skin thickness, Raynaud’s phenomenon, joint disorders, arterial and pulmonary hypertension, metabolic lipid dysfunctions is presented. Occupational history proves continuous duration of service at a job with occupational physical static load with numerous repetitive monotonous systematic motions of fingers and hands as a weaver of Persian rugs followed by work at an automated loom and variable labour activities. Though the complaints dated since the time she was a manual weaver, the manifestations of generalized joint degenerative changes, system sclerosis with Raynaud’s phenomenon with similar upper extremities signs and symptoms discount upper limbs musculoskeletal disorder as caused only or mainly by occupational risk factors. The main principles and criteria for occupational diagnosis of musculoskeletal upper limb disorders and legislative requirements for their reglamentation are discussed. PMID:27275213

Joint-action coordination in transferring objects

PubMed Central

Bosga, Jurjen; Hulstijn, Majken; Miedl, Stephan

2007-01-01

Here we report a study of joint-action coordination in transferring objects. Fourteen dyads were asked to repeatedly reposition a cylinder in a shared workspace without using dialogue. Variations in task constraints concerned the size of the two target regions in which the cylinder had to be (re)positioned and the size and weight of the transferred cylinder. Movements of the wrist, index finger and thumb of both actors were recorded by means of a 3D motion-tracking system. Data analyses focused on the interpersonal transfer of lifting-height and movement-speed variations. Whereas the analyses of variance did not reveal any interpersonal transfer effects targeted data comparisons demonstrated that the actor who fetched the cylinder from where the other actor had put it was systematically less surprised by cylinder-weight changes than the actor who was first confronted with such changes. In addition, a moderate, accuracy-constraint independent adaptation to each other’s movement speed was found. The current findings suggest that motor resonance plays only a moderate role in collaborative motor control and confirm the independency between sensorimotor and cognitive processing of action-related information. PMID:17256158

Optimization for Guitar Fingering on Single Notes

NASA Astrophysics Data System (ADS)

Itoh, Masaru; Hayashida, Takumi

This paper presents an optimization method for guitar fingering. The fingering is to determine a unique combination of string, fret and finger corresponding to the note. The method aims to generate the best fingering pattern for guitar robots rather than beginners. Furthermore, it can be applied to any musical score on single notes. A fingering action can be decomposed into three motions, that is, a motion of press string, release string and move fretting hand. The cost for moving the hand is estimated on the basis of Manhattan distance which is the sum of distances along fret and string directions. The objective is to minimize the total fingering costs, subject to fret, string and finger constraints. As a sequence of notes on the score forms a line on time series, the optimization for guitar fingering can be resolved into a multistage decision problem. Dynamic programming is exceedingly effective to solve such a problem. A level concept is introduced into rendering states so as to make multiple DP solutions lead a unique one among the DP backward processes. For example, if two fingerings have the same value of cost at different states on a stage, then the low position would be taken precedence over the high position, and the index finger would be over the middle finger.

Does finger training increase young children's numerical performance?

PubMed

Gracia-Bafalluy, Maria; Noël, Marie-Pascale

2008-04-01

Butterworth (1999) suggested that fingers are important in representing numerosities. Furthermore, scores on a finger gnosis test are a better predictor of numerical performance up to 3 years later than intellectual measures (Marinthe et al., 2001; Noël, 2005). We hypothesised that training in finger differentiation would increase finger gnosis and might also improve numerical performance. Accordingly, 47 first-grade children were selected and divided into 3 groups: children with poor finger gnosis who followed the finger-differentiation training programme (G1), a control-intervention who were trained in story comprehension (G2), and a group with high finger gnosis scores who just continued with normal school lessons (G3). The finger training consisted of 2 weekly sessions of half an hour each, for 8 weeks. Before the training period, children in G3 performed better in finger gnosis and enumeration than children in the two other groups. After the training period this pattern remained for the children in G2 and G3, but the children in G1 were significantly better than those in G2 at finger gnosis, representation of numerosities with fingers, and quantification tasks; they also tended to be better at the processing of Arabic digits. These results indicate that improving finger gnosis in young children is possible and that it can provide a useful support to learning mathematics. Such an approach could be particularly appropriate for children with a developmental Gerstmann syndrome. Theoretically, these results are important because they suggest a functional link between finger gnosis and number skills.

Wearable multifunctional sensors using printed stretchable conductors made of silver nanowires

NASA Astrophysics Data System (ADS)

Yao, Shanshan; Zhu, Yong

2014-01-01

Considerable efforts have been made to achieve highly sensitive and wearable sensors that can simultaneously detect multiple stimuli such as stretch, pressure, temperature or touch. Here we develop highly stretchable multifunctional sensors that can detect strain (up to 50%), pressure (up to ~1.2 MPa) and finger touch with high sensitivity, fast response time (~40 ms) and good pressure mapping function. The reported sensors utilize the capacitive sensing mechanism, where silver nanowires are used as electrodes (conductors) and Ecoflex is used as a dielectric. The silver nanowire electrodes are screen printed. Our sensors have been demonstrated for several wearable applications including monitoring thumb movement, sensing the strain of the knee joint in patellar reflex (knee-jerk) and other human motions such as walking, running and jumping from squatting, illustrating the potential utilities of such sensors in robotic systems, prosthetics, healthcare and flexible touch panels.Considerable efforts have been made to achieve highly sensitive and wearable sensors that can simultaneously detect multiple stimuli such as stretch, pressure, temperature or touch. Here we develop highly stretchable multifunctional sensors that can detect strain (up to 50%), pressure (up to ~1.2 MPa) and finger touch with high sensitivity, fast response time (~40 ms) and good pressure mapping function. The reported sensors utilize the capacitive sensing mechanism, where silver nanowires are used as electrodes (conductors) and Ecoflex is used as a dielectric. The silver nanowire electrodes are screen printed. Our sensors have been demonstrated for several wearable applications including monitoring thumb movement, sensing the strain of the knee joint in patellar reflex (knee-jerk) and other human motions such as walking, running and jumping from squatting, illustrating the potential utilities of such sensors in robotic systems, prosthetics, healthcare and flexible touch panels. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr05496a

ZifBASE: a database of zinc finger proteins and associated resources.

PubMed

Jayakanthan, Mannu; Muthukumaran, Jayaraman; Chandrasekar, Sanniyasi; Chawla, Konika; Punetha, Ankita; Sundar, Durai

2009-09-09

Information on the occurrence of zinc finger protein motifs in genomes is crucial to the developing field of molecular genome engineering. The knowledge of their target DNA-binding sequences is vital to develop chimeric proteins for targeted genome engineering and site-specific gene correction. There is a need to develop a computational resource of zinc finger proteins (ZFP) to identify the potential binding sites and its location, which reduce the time of in vivo task, and overcome the difficulties in selecting the specific type of zinc finger protein and the target site in the DNA sequence. ZifBASE provides an extensive collection of various natural and engineered ZFP. It uses standard names and a genetic and structural classification scheme to present data retrieved from UniProtKB, GenBank, Protein Data Bank, ModBase, Protein Model Portal and the literature. It also incorporates specialized features of ZFP including finger sequences and positions, number of fingers, physiochemical properties, classes, framework, PubMed citations with links to experimental structures (PDB, if available) and modeled structures of natural zinc finger proteins. ZifBASE provides information on zinc finger proteins (both natural and engineered ones), the number of finger units in each of the zinc finger proteins (with multiple fingers), the synergy between the adjacent fingers and their positions. Additionally, it gives the individual finger sequence and their target DNA site to which it binds for better and clear understanding on the interactions of adjacent fingers. The current version of ZifBASE contains 139 entries of which 89 are engineered ZFPs, containing 3-7F totaling to 296 fingers. There are 50 natural zinc finger protein entries ranging from 2-13F, totaling to 307 fingers. It has sequences and structures from literature, Protein Data Bank, ModBase and Protein Model Portal. The interface is cross linked to other public databases like UniprotKB, PDB, ModBase and Protein Model Portal and PubMed for making it more informative. A database is established to maintain the information of the sequence features, including the class, framework, number of fingers, residues, position, recognition site and physio-chemical properties (molecular weight, isoelectric point) of both natural and engineered zinc finger proteins and dissociation constant of few. ZifBASE can provide more effective and efficient way of accessing the zinc finger protein sequences and their target binding sites with the links to their three-dimensional structures. All the data and functions are available at the advanced web-based search interface http://web.iitd.ac.in/~sundar/zifbase.

Cradle and pressure grippers

DOEpatents

Muniak, John E.

2001-01-01

A gripper that is designed to incorporate the functions of gripping, supporting and pressure tongs into one device. The gripper has two opposing finger sections with interlocking fingers that incline and taper to form a wedge. The interlocking fingers are vertically off-set so that the opposing finger sections may close together allowing the inclined, tapered tips of the fingers to extend beyond the plane defined by the opposing finger section's engagement surface. The range of motion defined by the interlocking relationship of the finger sections allows the gripper to grab, lift and support objects of varying size and shape. The gripper has one stationary and one moveable finger section. Power is provided to the moveable finger section by an actuating device enabling the gripper to close around an object to be lifted. A lifting bail is attached to the gripper and is supported by a crane that provides vertical lift.

Multimodal biometric method that combines veins, prints, and shape of a finger

NASA Astrophysics Data System (ADS)

Kang, Byung Jun; Park, Kang Ryoung; Yoo, Jang-Hee; Kim, Jeong Nyeo

2011-01-01

Multimodal biometrics provides high recognition accuracy and population coverage by using various biometric features. A single finger contains finger veins, fingerprints, and finger geometry features; by using multimodal biometrics, information on these multiple features can be simultaneously obtained in a short time and their fusion can outperform the use of a single feature. This paper proposes a new finger recognition method based on the score-level fusion of finger veins, fingerprints, and finger geometry features. This research is novel in the following four ways. First, the performances of the finger-vein and fingerprint recognition are improved by using a method based on a local derivative pattern. Second, the accuracy of the finger geometry recognition is greatly increased by combining a Fourier descriptor with principal component analysis. Third, a fuzzy score normalization method is introduced; its performance is better than the conventional Z-score normalization method. Fourth, finger-vein, fingerprint, and finger geometry recognitions are combined by using three support vector machines and a weighted SUM rule. Experimental results showed that the equal error rate of the proposed method was 0.254%, which was lower than those of the other methods.

Effects of Finger Counting on Numerical Development – The Opposing Views of Neurocognition and Mathematics Education

PubMed Central

Moeller, Korbinian; Martignon, Laura; Wessolowski, Silvia; Engel, Joachim; Nuerk, Hans-Christoph

2011-01-01

Children typically learn basic numerical and arithmetic principles using finger-based representations. However, whether or not reliance on finger-based representations is beneficial or detrimental is the subject of an ongoing debate between researchers in neurocognition and mathematics education. From the neurocognitive perspective, finger counting provides multisensory input, which conveys both cardinal and ordinal aspects of numbers. Recent data indicate that children with good finger-based numerical representations show better arithmetic skills and that training finger gnosis, or “finger sense,” enhances mathematical skills. Therefore neurocognitive researchers conclude that elaborate finger-based numerical representations are beneficial for later numerical development. However, research in mathematics education recommends fostering mentally based numerical representations so as to induce children to abandon finger counting. More precisely, mathematics education recommends first using finger counting, then concrete structured representations and, finally, mental representations of numbers to perform numerical operations. Taken together, these results reveal an important debate between neurocognitive and mathematics education research concerning the benefits and detriments of finger-based strategies for numerical development. In the present review, the rationale of both lines of evidence will be discussed. PMID:22144969

Topographic generalization of tactile perceptual learning.

PubMed

Harrar, Vanessa; Spence, Charles; Makin, Tamar R

2014-02-01

Perceptual learning can improve our sensory abilities. Understanding its underlying mechanisms, in particular, when perceptual learning generalizes, has become a focus of research and controversy. Specifically, there is little consensus regarding the extent to which tactile perceptual learning generalizes across fingers. We measured tactile orientation discrimination abilities on 4 fingers (index and middle fingers of both hands), using psychophysical measures, before and after 4 training sessions on 1 finger. Given the somatotopic organization of the hand representation in the somatosensory cortex, the topography of the cortical areas underlying tactile perceptual learning can be inferred from the pattern of generalization across fingers; only fingers sharing cortical representation with the trained finger ought to improve with it. Following training, performance improved not only for the trained finger but also for its adjacent and homologous fingers. Although these fingers were not exposed to training, they nevertheless demonstrated similar levels of learning as the trained finger. Conversely, the performance of the finger that was neither adjacent nor homologous to the trained finger was unaffected by training, despite the fact that our procedure was designed to enhance generalization, as described in recent visual perceptual learning research. This pattern of improved performance is compatible with previous reports of neuronal receptive fields (RFs) in the primary somatosensory cortex (SI) spanning adjacent and homologous digits. We conclude that perceptual learning rooted in low-level cortex can still generalize, and suggest potential applications for the neurorehabilitation of syndromes associated with maladaptive plasticity in SI. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Evaluation of nutraceutical and antinutritional properties in barnyard and finger millet varieties grown in Himalayan region.

PubMed

Panwar, Priyankar; Dubey, Ashutosh; Verma, A K

2016-06-01

Five elite varieties of barnyard (Echinochloa frumentacea) and finger (Eleusine coracana) growing at northwestern Himalaya were investigated for nutraceutical and antinutritional properties. Barnyard millet contained higher amount of crude fiber, total dietary fiber, tryptophan content, total carotenoids, α-tocopherol compared to the finger millet whereas the finger millet contains higher amount of methionine and ascorbic acid as compared to the barnyard millet. The secondary metabolites of biological functions were analyzed and found that barnyard millet contained the higher amount of polyphenols, tannins and ortho-dihydroxy phenol content compared to finger millet. Among antinutitional compounds barnyard millet contained lower phytic acid content compare to finger millet whereas no significant difference in trypsin inhibition activity of barnyard millet and finger millet varieties were found. Barnyard millet contained higher acid phosphatase, α-galactosidase and α-amylase inhibitor activity compared to finger millet. Finger millet seeds contained about 10-13 folds higher calcium content and double amount of manganese content in comparison to barnyard millet seeds. Present study suggests that barnyard millet varieties studied under present investigation were found nutritionally superior compared to finger millet varieties.

Effects of endothelium-derived nitric oxide on skin and digital blood flow in humans.

PubMed

Coffman, J D

1994-12-01

The effects of NG-monomethyl-L-arginine (L-NMMA) on total finger and forearm, and dorsal finger and forearm skin, blood flows were studied in the basal state and during reflex sympathetic vasoconstriction in normal subjects. Total flows were measured by venous occlusion plethysmography and skin flows by laser-Doppler flowmetry (LDF). L-NMMA in doses of 2, 4, and 8 microM/min given by constant infusion via a brachial artery catheter significantly decreased finger blood flow, forearm blood flow, and vascular conductances. At 8 microM/min, total finger blood flow decreased 38.4% and forearm blood flow decreased 24.8%. Dorsal finger and forearm skin LDF were also significantly decreased (25 and 37% at 8 microM/min). Body cooling significantly decreased finger blood flow (73.6%), vascular conductance, and finger LDF (59.7%). L-NMMA had no effect on total finger blood flow or dorsal finger LDF during body cooling. Nitric oxide or related compounds contribute to the basal dilator tone of the dorsal finger and forearm skin but not during reflex sympathetic vasoconstriction.

Compliant finger sensor for sensorimotor studies in MEG and MR environment

NASA Astrophysics Data System (ADS)

Li, Y.; Yong, X.; Cheung, T. P. L.; Menon, C.

2016-07-01

Magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) are widely used for functional brain imaging. The correlations between the sensorimotor functions of the hand and brain activities have been investigated in MEG/fMRI studies. Currently, limited information can be drawn from these studies due to the limitations of existing motion sensors that are used to detect hand movements. One major challenge in designing these motion sensors is to limit the signal interference between the motion sensors and the MEG/fMRI. In this work, a novel finger motion sensor, which contains low-ferromagnetic and non-conductive materials, is introduced. The finger sensor consists of four air-filled chambers. When compressed by finger(s), the pressure change in the chambers can be detected by the electronics of the finger sensor. Our study has validated that the interference between the finger sensor and an MEG is negligible. Also, by applying a support vector machine algorithm to the data obtained from the finger sensor, at least 11 finger patterns can be discriminated. Comparing to the use of traditional electromyography (EMG) in detecting finger motion, our proposed finger motion sensor is not only MEG/fMRI compatible, it is also easy to use. As the signals acquired from the sensor have a higher SNR than that of the EMG, no complex algorithms are required to detect different finger movement patterns. Future studies can utilize this motion sensor to investigate brain activations during different finger motions and correlate the activations with the sensory and motor functions respectively.

Individual Finger Control of the Modular Prosthetic Limb using High-Density Electrocorticography in a Human Subject

PubMed Central

Fifer, Matthew S.; Johannes, Matthew S.; Katyal, Kapil D.; Para, Matthew P.; Armiger, Robert; Anderson, William S.; Thakor, Nitish V.; Wester, Brock A.; Crone, Nathan E.

2016-01-01

Objective We used native sensorimotor representations of fingers in a brain-machine interface to achieve immediate online control of individual prosthetic fingers. Approach Using high gamma responses recorded with a high-density ECoG array, we rapidly mapped the functional anatomy of cued finger movements. We used these cortical maps to select ECoG electrodes for a hierarchical linear discriminant analysis classification scheme to predict: 1) if any finger was moving, and, if so, 2) which digit was moving. To account for sensory feedback, we also mapped the spatiotemporal activation elicited by vibrotactile stimulation. Finally, we used this prediction framework to provide immediate online control over individual fingers of the Johns Hopkins University Applied Physics Laboratory (JHU/APL) Modular Prosthetic Limb (MPL). Main Results The balanced classification accuracy for detection of movements during the online control session was 92% (chance: 50%). At the onset of movement, finger classification was 76% (chance: 20%), and 88% (chance: 25%) if the pinky and ring finger movements were coupled. Balanced accuracy of fully flexing the cued finger was 64%, and 77% had we combined pinky and ring commands. Offline decoding yielded a peak finger decoding accuracy of 96.5% (chance: 20%) when using an optimized selection of electrodes. Offline analysis demonstrated significant finger-specific activations throughout sensorimotor cortex. Activations either prior to movement onset or during sensory feedback led to discriminable finger control. Significance Our results demonstrate the ability of ECoG-based BMIs to leverage the native functional anatomy of sensorimotor cortical populations to immediately control individual finger movements in real time. PMID:26863276

Individual finger control of a modular prosthetic limb using high-density electrocorticography in a human subject

NASA Astrophysics Data System (ADS)

Hotson, Guy; McMullen, David P.; Fifer, Matthew S.; Johannes, Matthew S.; Katyal, Kapil D.; Para, Matthew P.; Armiger, Robert; Anderson, William S.; Thakor, Nitish V.; Wester, Brock A.; Crone, Nathan E.

2016-04-01

Objective. We used native sensorimotor representations of fingers in a brain-machine interface (BMI) to achieve immediate online control of individual prosthetic fingers. Approach. Using high gamma responses recorded with a high-density electrocorticography (ECoG) array, we rapidly mapped the functional anatomy of cued finger movements. We used these cortical maps to select ECoG electrodes for a hierarchical linear discriminant analysis classification scheme to predict: (1) if any finger was moving, and, if so, (2) which digit was moving. To account for sensory feedback, we also mapped the spatiotemporal activation elicited by vibrotactile stimulation. Finally, we used this prediction framework to provide immediate online control over individual fingers of the Johns Hopkins University Applied Physics Laboratory modular prosthetic limb. Main results. The balanced classification accuracy for detection of movements during the online control session was 92% (chance: 50%). At the onset of movement, finger classification was 76% (chance: 20%), and 88% (chance: 25%) if the pinky and ring finger movements were coupled. Balanced accuracy of fully flexing the cued finger was 64%, and 77% had we combined pinky and ring commands. Offline decoding yielded a peak finger decoding accuracy of 96.5% (chance: 20%) when using an optimized selection of electrodes. Offline analysis demonstrated significant finger-specific activations throughout sensorimotor cortex. Activations either prior to movement onset or during sensory feedback led to discriminable finger control. Significance. Our results demonstrate the ability of ECoG-based BMIs to leverage the native functional anatomy of sensorimotor cortical populations to immediately control individual finger movements in real time.

Joint design of large-tip-angle parallel RF pulses and blipped gradient trajectories.

PubMed

Cao, Zhipeng; Donahue, Manus J; Ma, Jun; Grissom, William A

2016-03-01

To design multichannel large-tip-angle kT-points and spokes radiofrequency (RF) pulses and gradient waveforms for transmit field inhomogeneity compensation in high field magnetic resonance imaging. An algorithm to design RF subpulse weights and gradient blip areas is proposed to minimize a magnitude least-squares cost function that measures the difference between realized and desired state parameters in the spin domain, and penalizes integrated RF power. The minimization problem is solved iteratively with interleaved target phase updates, RF subpulse weights updates using the conjugate gradient method with optimal control-based derivatives, and gradient blip area updates using the conjugate gradient method. Two-channel parallel transmit simulations and experiments were conducted in phantoms and human subjects at 7 T to demonstrate the method and compare it to small-tip-angle-designed pulses and circularly polarized excitations. The proposed algorithm designed more homogeneous and accurate 180° inversion and refocusing pulses than other methods. It also designed large-tip-angle pulses on multiple frequency bands with independent and joint phase relaxation. Pulses designed by the method improved specificity and contrast-to-noise ratio in a finger-tapping spin echo blood oxygen level dependent functional magnetic resonance imaging study, compared with circularly polarized mode refocusing. A joint RF and gradient waveform design algorithm was proposed and validated to improve large-tip-angle inversion and refocusing at ultrahigh field. © 2015 Wiley Periodicals, Inc.

Saw injuries causing phalangeal neck fractures in adults.

PubMed

Al-Qattan, Mohammad M

2012-07-01

The outcome of adult phalangeal neck fractures caused by saws has not been previously investigated. Over a 15-year period, a total of 36 cases of saw-related injuries resulting in phalangeal neck fractures of the middle phalanx of the finger or the proximal phalanx of the thumb were treated. All injuries were industrial and covered by insurance. They were all adult males with type II fractures. The fracture were managed by K-wire fixation, immobilizing the distal joint only. The proximal joints were mobilized immediately after surgery and the K-wire was removed after 5 weeks. The following 2 patterns of saw injuries were observed: dorsal impact injuries resulting in a phalangeal neck fracture and concurrent extensor tendon injury (group I, n = 20 patients), and dorsolateral impact injuries resulting in concurrent extensor (± partial flexor) tendon and nerve injury (group II, n = 16 patients). The outcome with respect to range of motion and return to work was significantly better in the former group. Major complications such as nonunion, malunion, avascular necrosis of the phalangeal head, osteomyelitis, or contractures of the proximal interphalangeal joints were not observed. Two patients (1 in each group) had superficial pin-site infection. It was concluded that adult phalangeal neck fractures caused by saws is a separate entity from the previously reported series of closed phalangeal neck fractures in adults.

Multidigit movement synergies of the human hand in an unconstrained haptic exploration task.

PubMed

Thakur, Pramodsingh H; Bastian, Amy J; Hsiao, Steven S

2008-02-06

Although the human hand has a complex structure with many individual degrees of freedom, joint movements are correlated. Studies involving simple tasks (grasping) or skilled tasks (typing or finger spelling) have shown that a small number of combined joint motions (i.e., synergies) can account for most of the variance in observed hand postures. However, those paradigms evoked a limited set of hand postures and as such the reported correlation patterns of joint motions may be task-specific. Here, we used an unconstrained haptic exploration task to evoke a set of hand postures that is representative of most naturalistic postures during object manipulation. Principal component analysis on this set revealed that the first seven principal components capture >90% of the observed variance in hand postures. Further, we identified nine eigenvectors (or synergies) that are remarkably similar across multiple subjects and across manipulations of different sets of objects within a subject. We then determined that these synergies are used broadly by showing that they account for the changes in hand postures during other tasks. These include hand motions such as reach and grasp of objects that vary in width, curvature and angle, and skilled motions such as precision pinch. Our results demonstrate that the synergies reported here generalize across tasks, and suggest that they represent basic building blocks underlying natural human hand motions.

The multi-zinc finger protein ZNF217 contacts DNA through a two-finger domain.

PubMed

Nunez, Noelia; Clifton, Molly M K; Funnell, Alister P W; Artuz, Crisbel; Hallal, Samantha; Quinlan, Kate G R; Font, Josep; Vandevenne, Marylène; Setiyaputra, Surya; Pearson, Richard C M; Mackay, Joel P; Crossley, Merlin

2011-11-04

Classical C2H2 zinc finger proteins are among the most abundant transcription factors found in eukaryotes, and the mechanisms through which they recognize their target genes have been extensively investigated. In general, a tandem array of three fingers separated by characteristic TGERP links is required for sequence-specific DNA recognition. Nevertheless, a significant number of zinc finger proteins do not contain a hallmark three-finger array of this type, raising the question of whether and how they contact DNA. We have examined the multi-finger protein ZNF217, which contains eight classical zinc fingers. ZNF217 is implicated as an oncogene and in repressing the E-cadherin gene. We show that two of its zinc fingers, 6 and 7, can mediate contacts with DNA. We examine its putative recognition site in the E-cadherin promoter and demonstrate that this is a suboptimal site. NMR analysis and mutagenesis is used to define the DNA binding surface of ZNF217, and we examine the specificity of the DNA binding activity using fluorescence anisotropy titrations. Finally, sequence analysis reveals that a variety of multi-finger proteins also contain two-finger units, and our data support the idea that these may constitute a distinct subclass of DNA recognition motif.

The Multi-zinc Finger Protein ZNF217 Contacts DNA through a Two-finger Domain*

PubMed Central

Nunez, Noelia; Clifton, Molly M. K.; Funnell, Alister P. W.; Artuz, Crisbel; Hallal, Samantha; Quinlan, Kate G. R.; Font, Josep; Vandevenne, Marylène; Setiyaputra, Surya; Pearson, Richard C. M.; Mackay, Joel P.; Crossley, Merlin

2011-01-01

Classical C2H2 zinc finger proteins are among the most abundant transcription factors found in eukaryotes, and the mechanisms through which they recognize their target genes have been extensively investigated. In general, a tandem array of three fingers separated by characteristic TGERP links is required for sequence-specific DNA recognition. Nevertheless, a significant number of zinc finger proteins do not contain a hallmark three-finger array of this type, raising the question of whether and how they contact DNA. We have examined the multi-finger protein ZNF217, which contains eight classical zinc fingers. ZNF217 is implicated as an oncogene and in repressing the E-cadherin gene. We show that two of its zinc fingers, 6 and 7, can mediate contacts with DNA. We examine its putative recognition site in the E-cadherin promoter and demonstrate that this is a suboptimal site. NMR analysis and mutagenesis is used to define the DNA binding surface of ZNF217, and we examine the specificity of the DNA binding activity using fluorescence anisotropy titrations. Finally, sequence analysis reveals that a variety of multi-finger proteins also contain two-finger units, and our data support the idea that these may constitute a distinct subclass of DNA recognition motif. PMID:21908891

Trigger Finger (Stenosing Tenosynovitis)

MedlinePlus

... Trigger Finger Find a hand surgeon near you. Videos Trigger Finger Animation Trigger Finger Close Popup Close ... or "in." Also, avoid using media types like "video," "article," and "picture." Tip 4: Your results can ...

Selective Sensitization of Zinc Finger Protein Oxidation by Reactive Oxygen Species through Arsenic Binding*

PubMed Central

Zhou, Xixi; Cooper, Karen L.; Sun, Xi; Liu, Ke J.; Hudson, Laurie G.

2015-01-01

Cysteine oxidation induced by reactive oxygen species (ROS) on redox-sensitive targets such as zinc finger proteins plays a critical role in redox signaling and subsequent biological outcomes. We found that arsenic exposure led to oxidation of certain zinc finger proteins based on arsenic interaction with zinc finger motifs. Analysis of zinc finger proteins isolated from arsenic-exposed cells and zinc finger peptides by mass spectrometry demonstrated preferential oxidation of C3H1 and C4 zinc finger configurations. C2H2 zinc finger proteins that do not bind arsenic were not oxidized by arsenic-generated ROS in the cellular environment. The findings suggest that selectivity in arsenic binding to zinc fingers with three or more cysteines defines the target proteins for oxidation by ROS. This represents a novel mechanism of selective protein oxidation and demonstrates how an environmental factor may sensitize certain target proteins for oxidation, thus altering the oxidation profile and redox regulation. PMID:26063799

The influence of intrinsic sympathomimetic activity and beta-1 receptor selectivity on the recovery of finger skin temperature after finger cooling in normotensive subjects.

PubMed

Lenders, J W; Salemans, J; de Boo, T; Lemmens, W A; Thien, T; van't Laar, A

1986-03-01

A double-blind randomized study was designed to investigate differences in the recovery of finger skin temperature after finger cooling during dosing with placebo or one of four beta-blockers: propranolol, atenolol, pindolol, and acebutolol. In 11 normotensive nonsmoking subjects, finger skin temperature was measured with a thermocouple before and 20 minutes after immersion of one hand in a water bath at 16 degrees C. This finger cooling test caused no significant changes in systemic hemodynamics such as arterial blood pressure, heart rate, and forearm blood flow. The recovery of finger skin temperature during propranolol dosing was better than that during pindolol and atenolol dosing. There were no differences between the recoveries of skin temperature during pindolol, atenolol, and acebutolol dosing. Thus we could demonstrate no favorable effect of intrinsic sympathomimetic activity or beta 1-selectivity on the recovery of finger skin temperature after finger cooling.