So what have we learned? Well we have been kind enough to give you a brief rundown and take home message regarding the use of NMES for quadriceps strengthening during post-operative knee rehabilitation;
- Parameters; Biphasic/pulsed to maintain ROM, muscle re-education, preventing joint contractures or muscle atrophy, increasing blood flow, pain management and decreasing muscle spasm (best in early to intermediate stages), and Russian to improve muscle strength (best in intermediate to late stages).
- Dosage; according to the literature, to elicit strength gains in Quadriceps muscles post knee surgery (Russian parameter); 10-15min, 1x/day for 5 weeks, 15s:50s (on-off time) seems to be the general consensus. For earlier/acute stages; ALARA.
- NMES contraindications/precautions (post knee surgery); Contraindications - musculotendinous lesion, absence of a secure bony attachment of the muscle, superficial metal, DVT, Infection. Precautions - reduced sharp/blunt discrimination, broken skin.
- Increasing NMES frequency (>20Hz) does not increase muscle recruitment, it simply increases the rate of firing. Lower frequencies minimize electrical fatigue, thereby improving effectiveness of treatment especially in acute stages.
- NMES is effective in increasing quadriceps strength in both impaired and unimpaired knees. For optimal gains, NMES therapy combined with voluntary exercise produces significantly superior results.
- Younger and older populations benefit equally with short-term use, however in the long- term older populations may reap greater benefits as they are generally found to have diminished; baseline quadriceps strength pre/post surgery, motivation and adherence to rehabilitation relative to younger populations. However, NMES in addition to high-intensity volitional exercise produces comparable positive results regardless of one's age.
- NMES activates a similar proportion of voluntary capabilities and %MVIC in both sexes; therefore significant improvements in quadriceps strength occur postoperatively regardless of one's gender.