3-D Printed Orthotic Hand With Wrist Mechanism Using Twisted and Coiled Polymeric Muscles

2017 ◽  
Author(s):  
Ashvath Sharma ◽  
Lokesh Saharan ◽  
Yonas Tadesse
Keyword(s):  
Metacarpophalangeal Joint ◽  
Proximal Interphalangeal Joint ◽  
Interphalangeal Joint ◽  
Human Hand ◽  
Custom Made ◽  
Normal Hand ◽  
3D Printed ◽  
And Performance ◽  
Electrical Motors ◽  
Human Finger

Most stroke victims undergo muscular disorders leading to weakening of muscles and inability to perform normal hand activities. An exoskeleton device is therefore needed to aid in performing basic hand movements to improve the quality of life of the victims. Most of the available devices in literature are controlled using electrical motors with a rigid structure and complex design. This paper discusses the design and performance of an inexpensive and lightweight 3D printed orthotic device featuring a wrist mechanism. The design is simple and utilizes twisted and coiled polymeric (TCP) muscles which are easy to fabricate using a silver coated nylon 6, 6 threads. The device facilitates the movement of all the three joints of the human finger namely, distal interphalangeal joint (DIP), proximal interphalangeal joint (PIP) and the metacarpophalangeal joint (MCP). Experiments were performed using a custom-made hand which was 3D printed and casted using silicone rubber with a shore hardness 10 (Ecoflex® 010) to resemble an actual human hand. The results showed the range of motion achieved with the device, grasping and pinching of various objects with assistive efforts using TCP muscles and demonstrated the capability of the device to achieve flexion and extension of the fingers mimicking the human finger movements.

scholarly journals Design of 3D-Printed Cable Driven Humanoid Hand Based on Bidirectional Elastomeric Passive Transmission

2020 ◽  
Author(s):  
Te-Ru Chen ◽  
Xing-Wei Zhao ◽  
Guo-Cai Ma ◽  
Bo Tao ◽  
Zhou-Ping Yin
Keyword(s):  
Human Hand ◽  
Control Effect ◽  
Good Balance ◽  
Complex Part ◽  
Grasping Force ◽  
3D Printed ◽  
And Performance ◽  
Human Finger ◽  
The Cost ◽  
Humanoid Hand

Abstract Motion control of the human hand is the most complex part of the human body. It has always been a challenge for a good balance between the cost, weight, responding speed, grasping force, finger extension, and dexterity of prosthetic hand. In order to research and imitate the movement of the human hand, a 3D-printed cable driven humanoid hand based on bidirectional elastomeric passive transmission (BEPT) is designed in this paper. A semi-static model of BEPT is investigated based on energy conservation law to analyze the mechanical properties of BEPT. Then a simulation of dynamics of finger grasping is conducted. For a better imitation of human hand and a better grasping performance, specific BEPT is selected according to human finger grasping experiments. The advantage of BEPT based humanoid hand is that a good balance between the price and performance of the humanoid hand is achieved. Experiments proved that designed humanoid hand’s excellent grasping performance can be realized through BEPT. The designed prosthetic hand’s single fingertip force can reach 33N and has a good force control effect with 430g’s weight. It can not only grab fragile objects like raw eggs and paper cup, but also achieve strong grasping force to damage metal cans.

scholarly journals Design of 3D-printed Cable Driven Humanoid Hand Based on Bidirectional Elastomeric Passive Transmission

2021 ◽  
Vol 34 (1) ◽  
Author(s):  
Teru Chen ◽  
Xingwei Zhao ◽  
Guocai Ma ◽  
Bo Tao ◽  
Zhouping Yin
Keyword(s):  
Human Hand ◽  
Good Balance ◽  
Dynamical Simulation ◽  
Complex Part ◽  
Grasping Force ◽  
3D Printed ◽  
And Performance ◽  
Human Finger ◽  
The Cost ◽  
Humanoid Hand

AbstractMotion control of the human hand is the most complex part of the human body. It has always been a challenge for a good balance between the cost, weight, responding speed, grasping force, finger extension, and dexterity of prosthetic hand. To solve these issues, a 3D-printed cable driven humanoid hand based on bidirectional elastomeric passive transmission (BEPT) is designed in this paper. A semi-static model of BEPT is investigated based on energy conservation law to analyze the mechanical properties of BEPT and a dynamical simulation of finger grasping is conducted. For a good imitation of human hand and an excellent grasping performance, specific BEPT is selected according to human finger grasping experiments. The advantage of BEPT based humanoid hand is that a good balance between the price and performance of the humanoid hand is achieved. Experiments proved that the designed prosthetic hand’s single fingertip force can reach 33 N and the fastest fingertip grasping speed realized 0.6 s/180°. It also has a good force compliance effect with only 430g’s weight. It can not only grab fragile objects like raw eggs and paper cup, but also achieve strong grasping force to damage metal cans. This humanoid hand has considerable application prospects in artificial prosthesis, human-computer interaction, and robot operation.

Arthroplasty in the hand: what works and what doesn’t?

2021 ◽  
pp. 175319342110177
Author(s):  
Daniel B. Herren ◽  
Hajime Ishikawa ◽  
Marco Rizzo ◽  
Mark Ross ◽  
Michael Solomons
Keyword(s):  
Surgical Technique ◽  
Metacarpophalangeal Joint ◽  
Distal Radioulnar Joint ◽  
Proximal Interphalangeal Joint ◽  
Interphalangeal Joint ◽  
Carpometacarpal Joint ◽  
Thumb Carpometacarpal Joint ◽  
Radioulnar Joint ◽  
What Works ◽  
Thumb Carpometacarpal

This review describes the different possibilities for arthroplasties at the proximal interphalangeal joint, thumb carpometacarpal joint, distal radioulnar joint, metacarpophalangeal joint and the wrist. For each joint, the indication for arthroplasty is explained, the surgical technique with the suitable implant is described and a brief summary of the outcomes reported in the literature is given.

A proximal interphalangeal joint custom-made orthosis in trigger finger: Functional outcome

Hand Therapy ◽  
2021 ◽  
pp. 175899832110187
Author(s):  
Kawee Pataradool ◽  
Chayanin Lertmahandpueti
Keyword(s):  
Outcome Measures ◽  
Proximal Interphalangeal Joint ◽  
Interphalangeal Joint ◽  
Mean Difference ◽  
Trigger Finger ◽  
Symptom Improvement ◽  
Dash Score ◽  
Full Time ◽  
Custom Made ◽  
Quick Dash

Introduction Trigger finger is a common and functionally limiting disorder. Finger immobilization using an orthotic device is one of the conservative treatment options for treating this condition. The most common orthosis previously described for trigger finger is metacarpophalangeal joint immobilization. There are limited studies describing the effectiveness of proximal interphalangeal joint orthosis for treatment of trigger finger. Methods This study was a single group pretest-posttest design. Adult patients with single digit idiopathic trigger finger were recruited and asked to wear a full-time orthoses for 6 weeks. The pre- and post-outcome measures included Quick-DASH score, the Stages of Stenosing Tenosynovitis (SST), the Visual Analogue Scale (VAS) for pain, the number of triggering events in ten active fists, and participant satisfaction with symptom improvement. Orthotic devices were made with thermoplastic material fabricated with adjustable Velcro tape at dorsal side. All participants were given written handouts on this disease, orthotic care and gliding exercises. Paired t-tests were used to determine changes in outcome measures before and after wearing the orthosis. Results There were 30 participants included in this study. Evaluation after the use of PIP joint orthosis at 6 weeks revealed that there were statistically significant improvements in Quick-DASH score from enrolment (mean difference −29.0 (95%CI −34.5 to −23.4); p < 0.001), SST (mean difference −1.4 (95%CI −1.8 to −1.0); p < 0.001) and VAS (mean difference −3.4 (95%CI −4.3 to −2.5); p < 0.001). There were no serious adverse events and patient satisfaction with the treatment was high. Conclusions Despite our small study size, the use of proximal interphalangeal joint orthosis for 6 weeks resulted in statistically significant improvements in function, pain and triggering, and also high rates of acceptance in patients with isolated idiopathic trigger finger.

Extensor Indicis Opposition Transfer in The Ulnar and Median Palsied Thumb in Leprosy

1996 ◽  
Vol 21 (5) ◽  
pp. 617-621 ◽  
Author(s):  
R. MEHTA ◽  
G. N. MALAVIYA ◽  
S. HUSAIN
Keyword(s):  
Index Finger ◽  
Donor Site ◽  
Metacarpophalangeal Joint ◽  
Proximal Interphalangeal Joint ◽  
Interphalangeal Joint ◽  
Flexor Pollicis Longus ◽  
Extensor Pollicis Longus ◽  
Extensor Indicis Proprius ◽  
Leprosy Patients ◽  
Significant Deficit

Twenty seven opponensplasties for ulnar and median paralysis in 25 leprosy patients were performed using extensor indicis proprius. An additional transfer of the radial half of flexor pollicis longus to extensor pollicis longus was done to stabilize the metacarpophalangeal joint of the thumb. The biomechanical aspects of extensor indicis proprius tendon transfer were studied and results evaluated using various anatomical and functional parameters. Extensor indicis proprius provides adequate strength to position the thumb. However, sometimes it does not reach its new insertion. There is no significant deficit at the donor site but in a few cases the index finger may lose its capability for independent extension and sometimes a proximal interphalangeal joint contracture may develop.

Radiographic Assessment of the Relative Lengths of the Bones of the Fingers of the Human Hand

2002 ◽  
Vol 27 (6) ◽  
pp. 546-548 ◽  
Author(s):  
R. HAMILTON ◽  
R. A. DUNSMUIR
Keyword(s):  
Fibonacci Sequence ◽  
Proximal Interphalangeal Joint ◽  
Interphalangeal Joint ◽  
Human Hand ◽  
X Rays ◽  
Radiographic Assessment ◽  
Finger Tip ◽  
Distal Joint ◽  
Little Finger

The study assessed whether a relationship existed between the lengths of the phalanges of the fingers of the hand. The centres of rotation of the joints in each finger were determined by dissection of cadaveric hands. Using these data, the distances between the joint centres was determined on anteroposterior hand X-rays taken for clinical purposes. The study has shown that, for all the fingers, there is a ratio of1 for the distance between the metacarpophalangeal and proximal interphalangeal joint and the distance between the proximal interphalangeal joint and the finger tip. The ratio for the distances between the interphalangeal joints and the distal joint and the tip approximates to 1.3 for the index, middle and ring fingers and to 1.0 for the little finger. No evidence was found to support Littler’s hypothesis that the interarticular distances of the finger follow the Fibonacci sequence.

Rheumatology

2018 ◽  
Author(s):  
Chris Edwards ◽  
David Warwick
Keyword(s):  
Wound Healing ◽  
Tendon Rupture ◽  
Morning Stiffness ◽  
Metacarpophalangeal Joint ◽  
Early Morning ◽  
Proximal Interphalangeal Joint ◽  
Interphalangeal Joint ◽  
Erythrocyte Sedimentation ◽  
Key Features ◽  
Rheumatological Diseases

A number of rheumatological diseases are manifest in the hand and wrist. Many are associated with considerable systemic inflammation. This produces chronic ill-health, poor wound healing, and osteoporosis. Attempts to eliminate inflammation at the earliest opportunity are vital. Multiple involved joints with high acute phase markers (CRP and erythrocyte sedimentation rate raised) and early morning stiffness are key features. Multi-disciplinary management, involving the rheumatologist and hand therapist is essential. With improving medical management, surgical problems are becoming far less common. Typical conditions include metacarpophalangeal joint malalignment (ulnar drift, sagittal band subluxation), spontaneous arthrodesis, tenosynovitis, tendon rupture, and proximal interphalangeal joint imbalance (swan neck and boutonnière deformity).

Ulnar Parametacarpal Flap for Small Finger Avulsion Injury

2021 ◽  
Vol 26 (03) ◽  
pp. 477-480
Author(s):  
Shinsuke Takeda ◽  
Katsuyuki Iwatsuki ◽  
So Mitsuya ◽  
Miku Mitsuya ◽  
Yutaro Kuwahara ◽  
...  
Keyword(s):  
Proximal Phalanx ◽  
Metacarpophalangeal Joint ◽  
Proximal Interphalangeal Joint ◽  
Interphalangeal Joint ◽  
Island Flap ◽  
Skin Defect ◽  
Avulsion Injury ◽  
Propeller Flap ◽  
Alternative Method ◽  
Difficult Cases

In difficult cases of replantation following small finger avulsion injury, in which amputation occurs at the proximal interphalangeal joint, the ulnar parametacarpal island flap, rotated 180° (propeller flap), can be used as an alternative method for covering a skin defect of the proximal phalanx. This flap can prevent metacarpophalangeal joint dysfunction and additional finger shortening. We propose the use of an ulnar parametacarpal flap for this purpose and report the outcomes of two successful cases treated with this method and followed up for 12 months.

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