Biomechanics in prosthetic rehabilitation

Biomechanics in prosthetic rehabilitation. Participants: Shiza,Rameen,Tazmeen,Emaan.

A prosthesis substitutes for a part of the body that may have been missing at birth, or that is lost in an accident or through amputation. Many amputees have lost a limb as part of treatment for cancer, diabetes or severe infection.

Types of prosthetics: arm prostheses fitted at, above or below the elbow leg prostheses fitted at, above or below the knee Vertebral Colum prosthetics hand , foot, finger and toe prostheses artificial eyeballs ear, nose or eye socket replacements an artificial soft or hard palate (worn like a dental plate).

An understanding of biomechanics is important when working with amputees and people with prosthetic limbs. It is especially relevant to understanding how gait deviations and pressure problems occur and how they can be remedied.

PROSTHETIC REHABILITATION OF UPPER LIMB.

A prosthetic limb is defined as a mechanical device that is used to replace a missing human limb. The device is designed to help the user coordinate better control of an amputated limb. This could be as a result of motor control loss by a traumatic event, a congenital-related defect, or dyvascular -related..

COMPONENTS:.

User preferences need to be considered before designing a prosthetic limb and if focusing on a hand prosthesis, the following preferences are important:.

Grasp function for a size range of objects.

Intricate finger movements should be possible for grasping and pinching motions.

A prosthetic hand needs to be lightweight to allow for better movement in continuous space.

Published 2015. Finger projections need to be designed with active joints to allow for intricate movement.

Aesthetically, the prosthetic hand needs to appeal to the patient and allow for comfort of use.

BIOSENSORS: The use of biosensors is fundamental to initiating a pathway that will result in movement of the actuator. To allow for the control of a prosthetic limb, the actuators are attached to the residual part of an amputated area, which will provide feedback on tactile information generated by the biosensors. The actuators are also connected to a hardware interface system that acts as the controller, which initiates sensory feedback to the actuators..

The actuator is the key element to a fully functioning prosthetic hand and it is what displays the end result (i.e., grasping an object). To begin with, the actuator system to this prosthetic hand is made up of micro-actuators..

These drive the metacarpo -phalangeal (MP) joints of the thumb and the proximal interphalangeal (PI) joints. The distal interphalangeal (DIP) joint is controlled by a link connected to the proximal interphalangeal (PIP) finger joint..

ACTURATOR: It is important to consider the number of individual pieces of information that will predict how a certain parameter will behave (degrees of freedom [DOF]). With this in mind, it is known that each finger to a hand has 4 DOF and the wrist has 3 DOF, which means that a prosthetic hand has to be designed to function with 23 DOF.

It is quite difficult to control the movement of such a complex machine and so a basic two to three fingered prosthetic hand is usually designed for better control over the monitoring of signal patterns..

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The modeling of heavy actuators results in a lower DOF, which can affect the ability of the prosthetic hand to grasp objects effectively. The following video is a good example of a patient adapting a myoelectric prosthetic hand controller with signal activity being monitored..

EMG PROSTHESICS: to replicate the biomechanics of a human hand using biomimetic, mechanical design. The hands can be controlled via methods such as using electromyography signals from the residual limbs or by implanting tiny electrodes in the motor region of the brain or nerves responsible for controlling the hand. To control the movement of the fingers, new approaches have used cable-driven systems where strings replicate the tendons of the hand rather than conventional mechanical joints and transmission systems. This enabled the easier control of fingers as information about movement could be directly passed on to the prosthetic, rather than using complicated control systems..

The MSc ProsthetJe Harte. The latest designs combine machine learning and neural networks to enable a user to simply think of a movement and the prosthetic performs it, just like a natural limb. A recent study reported a prosthetic hand combined with a neural network that can allow the wearer to think and move the hand. Electrical signals from the nerves are measured through the skin and sent to a computer that decides what the movement should be. The computer learns what the movement should be using a neural network trained to recognize different movements..

TYPES:. 1.Body Powered Prostheses (Conventional ).

Body powered prostheses are the most common type of upper limb prostheses. They allow the prosthetic user to control the terminal device (usually a hook or a hand) via a harness system that fits around the chest and shoulder..

This type of prosthesis is reliable, durable and can be used in environments involving dust and water though it can be cumbersome and uncomfortable for some..

2.Externally Powered Prostheses (Myo-electric).

Externally powered prostheses use a battery powered electric motor to control the terminal device, eliminating the need of a harness system..

Sensors, embedded in the socket, pick up an EMG signal on the skin and transfer it to a processor which controls the functions of the motor. This motor then powers the elbow/wrist or terminal device. Intensive training with your prosthetics and occupational therapist is essential to ensure a successful outcome..

Many myo -electric devices come with training apps that you can use in the comfort of your own home. You can also add in custom movements or settings for your specific needs in most cases. There must be enough viable muscle sites to be considered a candidate for this style of prosthesis..

3.Cosmetic Prosthesis.

This type of prosthesis is traditionally considered purely cosmetic and does not provide functional restoration. However, there are many benefits and uses of ‘cosmetic’ Upper limb prosthetics, including but not limited to using as a support/brace when using your contralateral limb ( eg. Holding down paper with your prosthesis as you write ).

maintaining muscle usage/limiting wastage of the proximal muscles. Having the cosmetic prosthesis present is often beneficial for regaining a sense of self confidence, and often has a positive effect on mental health. A cosmetic glove is applied to match individual skin colour ..

4.Socket & Interface.

The purpose of the prosthetic socket is to transmit forces from the residual limb to the prosthesis. The socket suspension, interface/liner design and prescription will be chosen to work with you level of amputation, residual limb shape and available funding..

Prosthetic Leg.

An understanding of biomechanics is important when working with amputees and people with prosthetic limbs. It is especially relevant to understanding how gait deviations and pressure problems occur and how they can be remedied.

One of the most recent inventions is powering prosthetic limbs by the muscles in your existing limb to generate electrical signal and pulses. When electrodes are placed on the skin, it reads the muscle contractions and sends signals to the limb to move.

A lower-limb prosthesis is the mechanical device with which an amputee's residual limb interacts with the walking surface. The pressure and shear forces that affect the residuum due to prosthesis use are the sources of pain, residual-limb skin problems and gait deviations.

You can swim ,boat and can do a specific task with this.

PROSTHETIC REHABILITATION OF VERTEBRAL COLUMN. Spinal cord V e rte b ra Con u s rnedullaris equ 1 n a Disc T 10 Til T 12 Clivus Cervical Thoracic L urn bar Sacral Coccyx LLC.

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Meralgia paresthetica: Pathogenesis and Clinical Findings Spine/ Pelvis/Abdominal Pregnancy/Obesity Mechanical or Iatrogenic Pressure on LFCN (ie. belts, tight waistbands etc.) Idiopathic (commonly in: obese/pregnant pts, in 30-50 year old, Pt. with carpal tunnel syndrome) Compression/injury Of Lateral Femoral Cutaneous Nerve (LFCN) Meralgia paresthetica Sensory Symptoms only Diabetes Obesity Authors: Chaitanya Shah William F Hill Emily Ryznar Paul Bryan* • OIL) at time of publication Surgery Regions supplied by the LFCN Medial Metabolic injury/Neuropat hy Of LFCN Note: • • • • • Lateral Legend: Decreased sensation Dysesthesias (Tingling, Burning, Stinging, Stabbing) Negative Straight Leg Raise Test Straight leg raise test Symptoms are typically unilateral and rarely follow dermatomal distributions In most patients recovery is spontaneous within 3-6 months of symptom onset LFCN is a purely sensory nerve, thus symptoms are purely sensory Before diagnosis can be made, rule out: focal mass compression, spinal stenosis, lumbar arthropathies, intervertebral disc disease Following must be absent: lower back pain, constitutional or radicular symptoms, motor abnormalities (gait, strength, reflexes), palpable mass Pain on palpation Of lateral inguinal ligament (near anterior superior iliac spine) • With patient laying supine, passively flex the hip while keeping the knee straight on the side with pain • Stop when the patient feels pain. • Lower the leg until the pain resolves, when pain has resolved, rernain at that level and passively dorsiflex the foot • Pain felt shooting down the leg and radiating to below the knee is a positive Straight leg raise test. Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published January II, 2019 on www.thecalgaryguide.com.

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703,952 Exercises, 7t21 eatevy O Condition O Cl-C4 Tetraplegia C) CS Tetraplegia @ C6 Tetraplegia O C7-C8 Tetraplegia C) T I-LI Paraplegia C) L2-S1 Paraplegia O Motor incomplete SCI C) Traumatic brain injury C) Stroke C) Motor delay C) Aged O Exercise type O Body part O Equipment available O Exercise difficulty O Age category O Image orientation 119 180 199 182 276 741 833 195 115 Select text to display with exercise images.

Middle and Lower Trapezius Muscles: Method 1 While maintaining good sitting posture and with the arms slightly abducted and externally rotated, squeeze the shoulder blades down and together This exercise should precede the shoulder external rotation exercise with the resistance band. Middle and Lower Trapezius Muscles: Method 2 While lying in a supine position with the arms at approximately 450 of abduction, pinch the shoulder blades dO&vn and together. Extend the arrns against the mat for resistance. Anterior Attach a resistance band to the back the wheelchair or the knob Of a door on the side to be strengthened. Start with the shoulder blades pi nched dovvn and together. then punch the arm forward. Shoulder External Rotators Place a towel roll between the trunk and each arm. While keeping elbows bent to 900. grasp the resistance band. Pinch shoulder blades down and together. and then slowly pull hands apart-.

Real world Measured data Digital twin Modelled data.