The use of transcutaneous electrical nerve stimulation along with functional tasks for immediate pain relief in individuals with knee osteoarthritis

BACKGROUND

Knee pain is the major complaint in individuals with knee osteoarthritis (OA), and the effects of transcutaneous electrical nerve stimulation (TENS) on knee pain are controversial. The present study applied TENS along with functional tests to investigate its effect on pain level in individuals with mild to moderate knee OA.

METHODS

Twenty volunteers with knee OA classification of graded 2-3 performed four functional tests (stair climb test - SCT, timed up and go test - TUG, 6-minute walk test - 6MWT, knee extensor strength test - KES, and 2-step test from the locomotive syndrome risk test - LSR_2ST) while wearing either an active or inactive TENS. Knee pain level before and after each test was self-accessed by the visual analog scale (VAS). The effect of TENS (active vs. inactive) on pain level was submitted to statistical analyses.

RESULTS

Knee pain during SCT, TUG, and LSR_2ST tests was significantly lower when subjects used the active TENS, compared to using the inactive unit. The effect of the active TENS on pain level was also more significant in subjects with no anxiety or depression.

CONCLUSIONS

The results provided evidence of immediate pain relief in individuals with mild to moderate knee OA when TENS is applied along with functional activities, that usually induced pain in people with knee OA.

The effects of transcutaneous electrical nerve stimulation on strength, proprioception, balance and mobility in people with stroke: a randomized controlled cross-over trial

OBJECTIVE

To investigate the feasibility and potential efficacy of 'activeTENS' (that is transcutaneous electrical nerve stimulation (TENS) during everyday activities) by assessing the immediate effects on strength, proprioception, balance/falls risk and mobility after stroke.

DESIGN

A paired-sample randomized cross-over trial.

SUBJECTS

Twenty-nine mobile chronic stroke survivors with no pre-existing conditions limiting balance or mobility or contra-indications to TENS.

SETTING

University clinical research facility.

INTERVENTION

A single session of 'activeTENS' delivered via a 'sock electrode' (70-130 Hz, five second cycle) plus a session of control treatment (wearing the sock electrode with no stimulation), lasting approximately two hours in total.

MAIN OUTCOMES

Dorsiflexor and plantarflexor strength and proprioception using an isokinetic dyanometer, balance and falls risk (Standing Forward Reach Test) and gait speed (10-m walk test).

RESULTS

All participants tolerated 'active TENS'. Most parameters improved during stimulation with activeTENS; balance (p = 0.009), gait speed (p = 0.002), plantarflexor strength (p = 0.008) and proprioception of plantarflexion (p = 0.029), except dorsiflexor strength (p = 0.194) and dorsiflexion proprioception (p = 0.078).

CONCLUSIONS

The results provide initial evidence of the potential of 'active TENS' to benefit physical function after stroke which warrants further phase II trials to develop the intervention. Concerns that stimulation could have a detrimental impact on balance and increase risk of falls were not supported.