Evaluation of Electrical Nerve Stimulation (TENS) Therapy for Pain Relief Following Total Knee Arthroplasty (TKA)

Not Applicable

Completed

Brief Summary: Evaluation of Electrical Nerve Stimulation (TENS) Therapy for Pain Relieft Following Total Knee Arrhtoplasty (TKA)

Detailed Description: A prospective, randomized postmarket trial to assess the efficacy of the Select TENS™ Pain Management System, a transcutaneous electrical nerve stimulation (TENS) device, for reducing pain and narcotics requirement in patients managed with a total knee arthroplasty (TKA). This will be a placebo-controlled study involving 116 patients undergoing primary unilateral TKA procedures; 58 patients will be randomly selected to be treated postoperatively with an active TENS unit and the other 58 patients will be randomly selected to be treated with the placebo TENS unit (control group). Patients will be enrolled at two sites within the Cleveland Clinic Health System (Main Campus and Lutheran Hospital). Both treatment and control groups will receive a femoral nerve catheter, standard during a primary TKA. It is hypothesized that TENS (in combination with a femoral nerve catheter) can reduce narcotic usage, reduce pain, and allow for a quicker return to function following TKA.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

Patients who live >100 miles from the Cleveland Clinic main campus (9500 Euclid Ave., Cleveland, OH 44195)
Patients who will not receive a femoral nerve catheter for surgery
Patients who are not planned to be discharged directly home following surgery
Patients who have used a TENS device in the past
Preoperative daily use of narcotics (i.e., high tolerance)
Already enrolled in another research study, including the present study for contralateral knee
Patients with a history of epilepsy
Patients with a cardiac pacemaker
Patients who are a risk for poor compliance or have a poor understanding of the use of the TENS device
Condition deemed by physician or medical staff to be non-conducive to patient's ability to complete the study, or a potential risk to the patient's health and well-being.

Arm && Interventions

Group	Intervention	Description
Active TENS	EMPI Select TENS	Active TENS (EMPI Select TENS) in combination with a femoral nerve catheter. Patients will begin using the TENS unit immediately following surgery and continuing throughout the 6 weeks postoperatively.
Placebo TENS	Placebo EMPI Select TENS	Placebo TENS (Placebo EMPI Select TENS) in combination with a femoral nerve catheter. Patients will begin using a sham TENS unit (appears identical to Active TENS unit, yet is created to deliver low-level, non-therapeutic electrical stimulation) immediately following surgery and continuing throughout the 6 weeks postoperatively.

Primary Outcome Measures

Name	Time	Method
Narcotic Usage	Through 6 weeks after surgery	Morphine Equivalent dose, mg/kg

Secondary Outcome Measures

Name	Time	Method
Visual Analog Pain Score (VAS)	6 weeks (+/- 3 days) postoperative	Pain VAS is a continuous scale comprised of a vertical line, 10 centimeters in length, with each centimeter marked by its' corresponding whole number (1, 2, 3, etc.). It ranges from 0 to 10, with 0 being no pain and 10 being maximum pain.
Functional Assessments	6 weeks (+/- 3 days) postoperative	Timed up and go (TUG) test. These methods follows those published by Podsiadlo and Richardson, JAGS 1991; 39:142-148, in which the patient is observed and timed while he/she rises from an arm chair, walks 3 meters, turns, walks back, and sits down again.
General Health Outcome - SF-12 Physical Component Summary	6 weeks (+/- 3 days) postoperative	Physical Component Score. Physical Component Score (PCS) are computed using the scores of twelve questions and range from 0 to 100, where a zero score indicates the lowest level of health measured by the scales and 100 indicates the highest level of health. PCS provides emphasis on questions about general health, physical functioning and role playing and bodily pain. PCS is standardized using a z-score transformation and normed to a US population (Based on a 1990 norm) of a score of 50.0 and a standard deviation of 10.0. Normalized scores reported.