Electromyography (EMG)
Electromyography is the recording of electrical activity from muscle tissue. Muscles cells generate action potentials when electrically stimulated or under pathological conditions. An electromyograph detects these changes in electrical activity and represents an important diagnostic tool to monitor nerve root function and muscle cell activity.
Muscle and Neuromuscular Junction
Electromyography recording
EMG activity can be recorded using different types of electrodes, including monopolar needles, concentric needles, bipolar needles, and single-fiber needles. Without the use of high and low frequency filters, EMG signals would be very noisy and difficult to interpret. The low frequency filter should be set to 10-30 Hz and the high frequency filter to 10-20 kHz, for example.
- Spontaneous EMG. After the recording electrodes are inserted into the muscle tissue, the background EMG activity is stable and quiet under normal conditions. Spontaneous EMG activity generated by the motor unit or the muscle fiber occurs in the presence of an injury or a pathology. Examples of
- Stimulated EMG
- Single Fiber EMG
Peripheral Nerves
Cranial Nerves
- Facial Nerve
- Cranial Nerve III IV and VI
- Other Cranial Nerves
Intraoperative Monitoring
- Pedicle screws
- Peripheral Nerves
- Brachial Plexus
- Dorsal Rhizotomy
- Skull Base Tumor
- Others
Anesthesia and Other Factors
- Anesthesia Methods
- Muscle Relaxants
- Temperature
- Tourniquet
- Others