Diagnostic Strength Duration Curve

A strength duration curve is an electro-diagnostic test that maps how a muscle responds to electrical stimuli of varying duration. It helps characterise the integrity of the nerve supplying that muscle.

It is used in selected neurological cases — most commonly Bell's palsy, peripheral nerve injuries and recovery monitoring after trauma.

• Bell's palsy — early prognosis and follow-up
• Peripheral nerve injury monitoring
• Selected post-surgical nerve recovery cases
• Differentiating partial from complete denervation
• Tracking re-innervation over time
• Guiding electrotherapy parameters in nerve injuries

1. Referral ReviewWe review the referring clinician's notes and current findings.
2. Skin PreparationElectrode placement is cleaned and marked carefully.
3. Stimulus MappingStimuli of progressively shorter durations are delivered until a contraction is seen.
4. Curve PlottingThreshold values are plotted to produce the strength-duration curve.
5. InterpretationFindings are explained and shared with your referring clinician.

The test takes 30–45 minutes. Stimulation feels like a brief tap or twitch, not a shock.

Typically a single test per visit, repeated every 4–6 weeks if monitoring nerve recovery.

Cardiac pacemakers, broken skin at the site, severe local infection. Your physiotherapist will assess suitability.

• Diagnostic testing performed in-house — no second appointment elsewhere
• Findings are shared in writing with your referring clinician
• Used to guide rehabilitation, not as a stand-alone investigation