This video simplifies the concept of the Strength-Duration (SD) curve in electrotherapy, explaining how it is used to assess nerve injuries and determine if muscles are normally innervated, denervated, or partially innervated. You will learn the correct procedure for using an electrical muscle stimulator to plot this curve and how to interpret key clinical parameters like rheobase and chronaxie.
What you’ll learn?
- Purpose of Strength Duration Curve
- Equipment required for SD Curve testing
- Rules for accurate electrode placement and stimulation
- Plotting the graph: Selecting duration and intensity
- Example: Nerve injury analysis (Supra-condylar fracture)
- Normal muscle innervation graph
- Denervated muscle graph
- Partially innervated muscle graph
- Understanding the ‘Kink’ in the curve
- Defining Rheobase and Chronaxie
The SD curve is just one of several electrophysical agents used in clinical practice. Once you’re comfortable with electrical stimulation parameters here, it’s worth also reading up on therapeutic ultrasound, another widely used electrotherapy modality with its own dosage and application principles.
