physiotherapy,pulsed shortwave

1. Sreeraj S R
Pulsed Shortwave

2. Sreeraj S R
Pulsed Shortwave
• Pulsed electromagnetic energy (PEME)
• Pulsed electromagnetic field (PEMF)
• Pulsed electromagnetic energy treatment
(PEMET)
• Pulsed electromagnetic therapy (PEMT)

3. Sreeraj S R
Pulsed Shortwave
• PSWT involves a device that delivers an
electric and magnetic field in short pulses with
a time gap in between.
• PSW employs the same operating frequency
as traditional SWD i.e.. 27.12MHz.
• The mean power delivered to the patient is
relatively low even though the peak power
(i.e. during the on pulses) can be quite high up
to 1000W.

4. Sreeraj S R
Parameters
• Pulse Duration
the duration (time) of each
‘ON’ phase.
25 – 400 µs
• Pulse Repetition Rate
the number of pulses
delivered per second.
15 – 800 Hz
• Peak Pulse Power
The amplitude of the
pulse / intensity.
100 – 1000 W
• Mean Power
Power delivered from the
machine (during pulse and
averaged)

5. Sreeraj S R
PSWD Mean Power Calculations
• MP (W) = PP (W) x PW (s) x PRR (Hz)
• MP (W) = 250 W x 400µs x 145Hz
• MP (W) = 14.5W
• A microsecond is one millionth (10−6) of
a second so
• 400 µs is 400 x 10-6 s

6. Sreeraj S R
Machine Output
• ELECTRIC field, comparable
to the condenser (capacitor)
field in traditional SWD
• MAGNETIC field, comparable
to inductothermy.

7. Sreeraj S R
Tissue Heating
• No accumulation
• More non thermal
• Both thermal and non
thermal

8. Sreeraj S R
Mechanism of Effect

9. Sreeraj S R
Primary Effects of PSWD
1. Increased number of white cells, fibroblasts etc in
a wound.
2. Improved rate of edema dispersion.
3. Encourages absorption of heamatoma.
4. Reduction (resolution) of the inflammatory
process.
5. Prompts a more rapid rate of orientation &
deposition of collagen.
6. Encourages collagen layering at an early stage.
7. Stimulation of osteogenesis.
8. Improved healing of the peripheral & central
nervous systems

10. Sreeraj S R
Treatment Doses
Acute conditions
• Mean power of less than 3 Watts.
• Time : 10 – 15 minutes
Sub Acute Conditions
• Mean power of between 2 and 5 Watts
• Time : 15 minutes
Chronic Conditions
• Mean power of more than 5 Watts
• Time : 15 – 20 minutes

11. Sreeraj S R
Contraindications
• Pacemakers
• Pregnancy
• Tissue bleeding
• Malignancy
• Active tuberculosis
• Active epiphyseal regions in children
• Severe circulatory compromise
• Deep X Ray therapy or other ionizing radiations (in the last
6 months)
• Patients who are unable to comprehend the therapists
instructions
• Metal in the tissues
• Menstruation
• Specialized tissues (e.g. eye and testes)

12. Sreeraj S R
SWD vs. PSW
SWD PSW
Electromagnetic energy absorption
Thermal Non Thermal
400 – 500 W max. output Max. mean output in the region of
40 W
↑ molecular KE and heat • primary effects appears to be at
the cell membrane level &
transport of ions across the
membrane.
• Cell ion binding properties
• Cell membrane potentials
• Protein synthesis
• cellular energy (ATP)
↑ Cell metabolism
Enhance soft tissue healing

13. Sreeraj S R
References
1. http://www.electrotherapy.org/modalities/pswt.htm
2. http://sprunig.net/wp-content/uploads/Use-of-different-doses-of-
pulsed-short-waves-in-the-treatment-of-patients-with-osteoarthritis-
of-the-knee_2008.pdf
3. http://www.healthcentre.org.uk/physiotherapists/physiotherapist-
pulsed-shortwave-therapy.html