1 / 13

IE 552 Mechanics of Musculoskeletal System Dr. Andris Freivalds Class #31

IE 552 Mechanics of Musculoskeletal System Dr. Andris Freivalds Class #31. Nerve Conduction Waveform. Changes Over Time. Onset Latency Nerve Conduction Velocity. Limitations of Nerve Conduction. Individual variations Temperature –NCV ↓ as Temp ↓ Age effect –

sydnee-case
Download Presentation

IE 552 Mechanics of Musculoskeletal System Dr. Andris Freivalds Class #31

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. IE 552 Mechanics of Musculoskeletal System Dr. Andris Freivalds Class #31 IE 552

  2. Nerve Conduction Waveform IE 552

  3. Changes Over Time Onset Latency Nerve Conduction Velocity IE 552

  4. Limitations of Nerve Conduction • Individual variations • Temperature –NCV ↓ as Temp↓ • Age effect – NCV ↓ as age ↓ • BMI (gender) effect IE 552

  5. Electromyography • Electromyography (EMG) – electrical activity in muscles • Nerve AP to motor endplate • Muscle AP and Ca++ release • Actin and myosin crossbridging • Muscle contraction and force production • A measure of: • Muscle activation • Muscle force (indirectly) • Medical disorders IE 552

  6. EMG Instrumentation - 1 • Electrodes • Surface (noninvasive) vs. needle (invasive) • Bipolar vs. unipolar • Placement, preps, electrical impedance • Preamplifier • High input impedance • Signal-to-noise ratio IE 552

  7. EMG Instrumentation - 2 • Amplifier • Bandwidth • Gain • Portable • Safety • Signal processor IE 552

  8. EMG Analysis – 1Smoothed-Rectified Signal • Root-mean-squared (RMS) EMGRMS – [∫ v2(t)dt/T]½ • Smoothed-rectified • Passed through RC circuit • Integrated • Charged over a capacitor • Normalization EMGnorm = (EMGi – EMGmin)/(EMGmax – EMGmin) IE 552

  9. Motor Unit Recruitment Rate Coding EMG-Force Relationship EMG Analysis – 2EMG Amplitude vs. Force IE 552

  10. EMG Analysis – 3Frequency Analysis EMG Power Spectrum IE 552

  11. Sincere Faker EMG Analysis – 3Efficiency of Electrical Activity IE 552

  12. EMG Analysis – 4Amplitude Distribution Analysis IE 552

  13. Amplitude Distribution Example IE 552

More Related