Clinical studies suggest that AL-TENS, acupuncture-like transcutaneous electrical nerve stimulation (TENS), is effective for treating many types of pain and physical dysfunction. To date, only a few studies have compared the TENS and AL-TENS forms of stimulation, and no studies have compared the efficacy of conventional TENS and AL-TENS in patients who have undergone total knee arthroplasty (TKA).
The study intended to determine (1) the efficacy of conventional TENS and AL-TENS for TKA patients and (2) which outcomes-pain at rest, movement-evoked pain, and physical function-were most likely to be affected by conventional TENS compared with AL-TENS for people with pain, to inform the design of future studies.
The research team designed a single-blind, randomized clinical trial with randomized treatment allocation.
The study took place at the Orthopedic and Rehabilitation Hospital of Jeonju (Jeonju, South Korea).
Participants were 30 patients at the hospital who had undergone TKA.
Participants were randomly assigned to 1 of 2 groups, TENS or AL-TENS, and received the relevant intervention at selected points for knee pain. Each group received treatment for 30 min per visit, 5 times per wk, for 2 wk during the study.
Outcome measures were pain intensity, measured with a visual analogue scale; knee functional mobility, measured with the Western Ontario and McMaster Universities Osteoarthritis Index and with the Timed Up & Go Test; and inflammation, measured by the C-reactive protein level. Data were collected at baseline and postintervention.
Changes in pain, knee function, knee mobility, and inflammation between baseline and postintervention were statistically significant for both groups (P < .05). Changes in pain, stiffness, and inflammation between baseline and postintervention were significantly greater for the AL-TENS group compared with TENS group (P < .05).
AL-TENS was more effective than TENS with respect to pain, stiffness, and inflammation relief for patients following TKA.

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