Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Electrical Stim. Functional

No description

Matthew Kimball

on 16 November 2010

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Electrical Stim. Functional

Functional Electrical Stimulation “devices help restore movement to paralyzed muscles by controlling the electrical signals used to stimulate nerves and muscle tissue. The devices translate input from transducers or other devices that the patient can control into complex stimulus pat¬terns that produce the desired motion in paralyzed or uncontrollable muscles.” Applications Restoring hand and arm function to persons with quadriplegia Enabling paraplegic patients to stand and walk Improving motor control and gait after stroke Restoring bladder and bowel function Improving tissue health by preventing pressure sores Each application uses a combination of one or more implanted stimulators, percutaneous electrodes, or surface electrodes to produce movement. Resources Trier, S., Vrabec, T., Weisgarber, J. “Using Functional Electrical Stimulation to Restore Movement to Individuals with Neuromuscular Disabilities”, Cleveland FES Center and Case Western Reserve University Department of Biomedical Engineering Sacral stimulators are surgically implanted FES systems for on-demand control of the paralyzed bladder and bowel; these have been implanted in more than 1,500 paralyzed people, mostly in Europe. The stimulator, called the Finetech-Brindley device, has a strong track record for improving bladder and bowel control in the vast majority of users http://www.christopherreeve.org/site/c.mtKZKgMWKwG/b.4453425/k.27A5/Functional_Electrical_Stimulation.htm FES has been employed in the rehabilitation of stroke patients. It has been utilized to manage contracture of joints, maintain range of motion, facilitate voluntary motor control, and reduce spasticity On upper extremities of stroke patients: electrical stimulation has a positive effect on motor control Physics Principles and Techniques •Uses electrical current to stimulate and heal muscle groups Electrical current: flow of positively charged particles from a higher voltage(anode) to lower voltage (cathode). Frequency: rate at which pulses are applied Pulse width: duration of a pulse (100-500 microseconds) Indications for this test -Relaxation of muscle spasm
-Prevention of retardation of disuse atrophy
-Increasing local blood circulation
-Muscle re-education
-Immediate post surgical stimulation of calf muscles to prevent venous thrombosis
-Maintaining or increasing range of motion
-Used to rehabilitate muscles after injury or stroke
-Effective enough to cause an actual muscle contration
-This improves the strength of muscles and also muscle tone.
-Nerve impulse goes through motor point to have muscle expand and contract.
-Has effects of actual exercise
-Difference is that there is no signal being sent to the brain to get the muscles to contract. How E-STIM works •Electrical current is used to stimulate and heal muscle groups.
•Threshold Potential
–Amount of electrical current that causes muscles to contract.
–Ions move from EMS machine into muscles groups
–When it reaches the threshold then muscles contract.
•High Voltage EMS is typical for of therapeutic use.
–100V -500V •Three different types of currents used
•continuous one directional flow of ions.
•continuous two directional flow of ions.
Pulse flow
•Flow of ions either AC or DC that is briefly interrupted periodically.
•Current change must be sudden.
Muscles have adaptive capabilities which allow them to be able to control their contractions.
•Treatment can be manipulated by changing
Frequency of current
Intensity of current
Duration of the pulse. (430 ms to 200 ms) •Number of waves occurring per unit of time
•Strength- 50Hz-80 Hz
•Toning- 12.5 Hz
•Building Muscles- 33 Hz
•TENS- 2Hz-50Hz Conductors vs. Resistors •Important for placement of electrodes.
•Each muscle group has a different place to set electrodes based on the
Origin and Insertion
Number of conductors/resistors in that area.
•Conductors: promote electrical current.
•Resistors: inhibit electrical current.
Fat HISTORY RISKS How are they used in medicine and the physiological conditions? How do the tests work? •For example if a person has drop foot a small, self-contained device attaches to the leg below the knee, counteracting foot drop by electronically stimulating the peroneal (sometimes called fibular) nerve, thus allowing foot lifting. During the swing phase of walking, the device electrically stimulates the appropriate muscles that cause ankle dorsiflexion and may thus improve the person’s walking ability. http://article.pubs.nrc-cnrc.gc.ca/ppv/RPViewDoc?issn=1205-7541&volume=82&issue=8-9&startPage=784 http://www.nationalmssociety.org/about-multiple-sclerosis/what-we-know-about-ms/treatments/rehabilitation/functional-electrical-stimulation/index.aspx http://fescenter.org/index.php Functional electrical stimulation (FES) is a technique that uses electrical currents to activate nerves innervating extremities affected by paralysis resulting from spinal cord injury (SCI), head injury, stroke and other neurological disorders. FED is primarily used to restore function in people with disabilities. It is sometimes referred to as Neuromuscular electrical stimulation (NMES)[1]. Originally used to help treat foot drop 1967 Moe and Post changed the name Functional Electrotherapy 1991 several universities began using FES to help awaken coma patients 1994 FDA approved FES devices have helped abulate injured persons walk upwards
1 mile unassisted Increased bone density Increased blood flow Quicker nerve impulse return Chronic stimulation — Effects of long-term chronic stimulation are unknown in this particular application. Monitoring equipment Electrodes Pregnancy Hospital equipment — Do not use simultaneously with high frequency hospital equipment (e.g. diathermy equipment). It may result in burns at the site of the stimulator electrodes and possible damage to the stimulator. Skin irritation Two-way radios Defibulator •Functional electrical stimulation is a technique that uses low levels of electrical currents that stimulate nerves, innervating extremities that have been impaired usually due to a spinal cord injury, head injury, stroke or other nerve disorders. •It can control movement and produce “otherwise paralyzed limb” in standing and voluntary hand movements such as grasping. Also it can decrease pain or spasms, and help a natural recovery and accelerate motor relearning. • Potential benefits include improved blood return from lower limbs, prevents osteoporosis, decreases urinary infections, and retaining muscle mass. Psychological benefits can result from improved functionality and greater independence. •Chronic FES has shown to improve mobility, reduce spasticity, improve cardiovascular fitness, and enables a person to participate in activities that will increase function. •FES is not a cure but may restore or improve function in nerves that control specific muscles or muscle groups. •FES uses low levels of electrical current to stimulate bodily or physical functions or lost through nervous system impairment (1-7). FES is applied to peripheral nerves that control specific muscles or muscle groups. •FES uses a feedback or control unit, leads, an electric stimulator and electrodes. The stimulators can have more than one output which can be activated together or in a sequence, this is depending on the moments which are wanted. •The electrodes can be outside of the body or surgically implanted, this depends mostly on the patients needs. The electrodes also serve as interfaces between the electrical stimulator and nervous system. •The FES systems that are therapist operated use switches or dials where as the subject contelled can use joysticks, switches, joint position sensors, and voice activation. Also subject controlled can be open or closed loop. The open loop is there the electrical stimulator controls the output and in the closed loop the FES employs joint or muscle position sensors to increase a greater response to muscle fatigue or other irregularities.
Full transcript