Wireless neuromodulation for chronic knee pain relief

Inclusion Criteria:

i. Subject is over 18 years of age; ii. Subjects with a history of chronic, function-limiting (m-MPS \>6/10) knee pain from osteoarthritis of at least three months in duration with or without prior surgeries; iii. Subject has been diagnosed with Kellgren-Lawrence Grade II or III knee osteoarthritis, confirmed by X-ray studies conducted in the last year; iv. Subject has been examined and has been deemed to be an appropriate candidate for the procedure, including chronic knee pain in patients post total knee replacement (TKR); v. Subjects who are able to understand this investigation, and give voluntary, written informed consent to participate in this study; vi. Subjects who are able to co-operate with the study procedures and are willing to return to the center for all the required post-operative follow-ups; vii. Documented failure of at least two less invasive treatment modalities including physical therapy, intra-articular steroids and/or oral NSAIDS; viii. Subject has not had recent invasive surgical procedures of the knee within the following intervals in relation to the time of signing Informed Consent:- 2 weeks for steroid injection - 4 weeks for radiofrequency, cryoablation or hyaluronic acid (HA) injection ix. Subject noted good (\> 75%) but only temporary relief for at least 2 hours from an infrapatellar saphenous nerve injection with local anesthetic; x. Subject is deemed to be neuro-psycho-socially appropriate for implantation therapies based of assessment of a Clinical Psychologist.

Exclusion Criteria:

xi. Significant contralateral knee pain that would influence their level of activity greater to 6 on the modified-Mankosky Pain Scale; xii. Hip or foot pain greater than knee pain; xiii. Neurogenic or vascular claudication; xiv. Subject has been diagnosed with Kellgren-Lawrence Grade IV knee osteoarthritis, confirmed by X-ray studies conducted in the last year; xv. Uncontrolled major depression or uncontrolled psychiatric disorders; xvi. Uncontrolled or acute medical illnesses including coagulopathy, renal insufficiency, chronic liver dysfunction, progressive neurological deficit, infection, unstable angina, and severe chronic obstructive pulmonary disease; xvii. Chronic severe conditions that could interfere with the interpretations of the outcome assessments for pain and bodily function (eg. Rheumatoid arthritis, severe spinal stenosis, activity-limiting cardiac disease); xviii. Women who are pregnant or planning to become pregnant, lactating; xix. Body mass index (BMI) greater than 40 (morbid obesity); xx. Subjects with multiple complaints involving concomitant knee, foot, or ankle pathology or radiculopathy, that will not be amenable to study due to the overlap of pain complaints; xxi. Subject has been examined and has been deemed to be inappropriate for the procedure based on anatomical restrictions; xxii. Lymphedema or stasis ulcers or other conditions that would compromise the surgical site; xxiii. History of adverse reaction to local anesthetic drugs; xxiv. Worker's compensation claimants; xxv. Incarcerated or has an ankle position locator; xxvi. Documented allergy to device material components; xxvii. Known or suspected substance abuse within the last 2 years; xxviii. Pacemaker or implanted defibrillator; xxix. Participation in another clinical study that could confound the results of this study; xxx. Based on the opinion of the investigator any legal or medical concerns that would preclude his/her enrollment in the study or potentially confound the results; xxxi. Any other implanted active medical devices in the same site.