Pilot Study of PEMF Therapy in Treatment of Post-operative Pain Following Total Knee Arthroplasty

This is a multi-site randomized, double-blinded, parallel-group prospective pilot study of the analgesic effectiveness of twice-daily PEMF therapy in the treatment of persistent post-operative pain following Total Knee Arthroplasty (TKA). Following a run-in period of 10 days to collect their baseline pain intensity scores, activity levels and opioid consumption, eligible subjects will be randomized in a 2:1 ratio to receive therapy with an active PEMF device or an identical inactive Sham device. Subjects will self-treat twice daily for 60 days while at home. Subjects will collect electronic patient-reported outcome (ePRO) data each morning through Day 75. Subjects will be evaluated at the research center for Interim Visits at Day 21, Day 41, Day 61 and Day 75 for assessment of safety, concomitant medications, range of motion, weight, peripheral edema, and quality of life outcomes. At Day 90, Day 150, and Day 240 assessment of pain intensity, opioid consumption, safety, review of concomitant medications and interval history will be performed, with data collected via telephone contact.

Inclusion criteria

• Subject age is greater or equal to 18 years.
• Subject has undergone a total knee replacement for the treatment of osteoarthritis, and has persistent post-operative pain in the index knee for > 3 months and < 36 months following surgery.
• Subject has been receiving medication for persistent post-operative knee pain, including opioid or non-opioid analgesic medication that is administered on an "as needed" (prn) basis, and is on a stable analgesic dosing regimen (i.e. the same medications and dosages) for > 30 days prior to the screening visit.
• Mean Pain Intensity (calculated as the mean of the daily average pain intensity scores) is ≥3 and < 9 as measured on Numeric Pain Rating Scale (NPRS) during the run-in phase.
• Subject has completed a minimum of 80% (8 of 10 possible) of the pain intensity assessments during the run-in phase.
• Subject is willing and able to wear an activity meter from the screening visit through Day 75.
• Subject is able to access an internet browser in the home environment.
• Subject is willing and able to give written informed consent and to comply with all parts of the study protocol.
• Female Subjects must be post menopausal, surgically sterile, abstinent, or practicing (or agree to practice) an effective method of birth control if they are sexually active for the duration of the study. (Effective methods of birth control include prescription hormonal contraceptives, intrauterine devices, double-barrier methods, and/or male partner sterilization).

Exclusion criteria

• Subject has undergone simultaneous bilateral knee arthroplasty or revision arthroplasty on the index knee.
• Subject requires revision surgery prior to Day 75.
• Subject has undergone manipulation under anesthesia of the index knee or any local injection into the index knee within 30 days prior to the Screening Visit, or within 6 weeks prior to the Screening Visit for long acting lidocaine injection products.
• Subject has received any investigational drug or device within 30 days prior to the Screening Visit or is enrolled in another clinical trial.
• Subjects consuming an average of > 100 mg oral Morphine Sulfate equivalents per day during the run-in phase.
• Subject has evidence on physical or radiological exam of joint instability or infection involving the index knee.
• Passive range of motion demonstrates maximal flexion of the index knee < 90 degrees or maximal extension of the index knee < -10 degrees.
• Body Mass Index (BMI) < 19 kg/m2, or > 38 kg/m2.
• Subject has a history of any uncontrolled medical illness that in the investigator's judgment places the subject at unacceptable risk for receipt of Provant therapy.
• Subject has an ongoing painful condition that in the opinion of the Investigator might have a confounding influence on the safety or effectiveness analysis for this study.
• Use of systemic corticosteroids within 2 months of the Screening visit.
• Subject anticipates the need for surgery of any type through the Day 75 visit.
• Subjects whom, in the judgment of the Investigator, have serious psychosocial co-morbidities.
• History of drug or alcohol abuse within one year prior to screening.
• Subject has a history of malignancy within the past five years other than successfully treated non-metastatic basal cell or squamous cell carcinomas of the skin in the treatment area and/or localized carcinoma in situ of the cervix.
• Subject has an implanted pacemaker, defibrillator, neurostimulator, spinal cord stimulator, bone stimulator, cochlear implant, or other implanted device with an implanted metal lead(s).
• Existing or planned pregnancy.
• Subject has been previously treated with study device.
• Subject is in current litigation related to the index knee or is receiving Worker's Compensation for an injury related to the index knee.
• Subject is unwilling or unable to follow study instructions, comply with the treatment regimen, study visits, and ePRO assessments.
• Standard deviation around the mean of the average pain intensity scores during the run-in period is >2.0.