This study will evaluate the iovera° device in treating pain associated with total knee arthroplasty (TKA). This study will also assess if overall pain medication is reduced following TKA and will investigate the relationship between patients treated with the iovera° device and length of hospital stay, pain, patient satisfaction and improved rehabilitation.

Inclusion Criteria:

• 22 to 79 years of age
• Scheduled to undergo primary unilateral TKA under spinal anesthesia for primary diagnosis of osteoarthritis
• American Society of Anesthesiology (ASA) Physical Classification System classes I-III
• Anticipation of discharge to home after inpatient acute post-op phase (age, co-morbidities, home environment, and social support are in favor of discharge to home in the opinion of the Investigator)
• Subject is willing and able to give written informed consent.
• Subject is fluent in verbal and written English.
• Subject is willing and able to comply with study instructions and commit to all follow-up visits for the duration of the study.
• Subject is in good general health and free of any systemic disease state or physical condition that might impair evaluation or which in the Investigator's opinion, exposes the Subject to an unacceptable risk by study participation.

Exclusion Criteria:Exclusion Criteria

• Chronic opioid use (defined as daily or almost daily use of opioids for >3 months).
• Concurrent painful physical condition, surgery, or musculoskeletal disease that requires or may require analgesic treatment during study follow-up that is not strictly related to the target knee being treated with iovera°, which have the potential to confound the postoperative assessments (e.g., significant pain from other joints, chronic neuropathic pain, concurrent or planned contralateral TKA, concurrent foot, neck, spine, hip, or other musculoskeletal disease, arthritis, or planned surgery, etc.).
• Greater than 15° malalignment (varus or valgus) on pre-operative radiograph.
• Previous myoscience FCT™ treatment.
• Previous Partial or Total Knee Arthroplasty. Partial or Total Knee Arthroplasty of the contralateral knee is permitted if [surgery was completed at least twelve (12) months prior to screening].
• Body Mass Index ≥ 40
• Prior surgery in the treatment areas that may alter the anatomy of the infrapatellar branch of the saphenous nerve (ISN) or the anterior femoral cutaneous nerve (AFCN) or result in scar tissue in the treatment area.
• Any clotting disorder and/or use of an anticoagulant (e.g. warfarin, clopidogrel, etc.) within seven (7) days prior to administration of the device. Low dose aspirin (81mg or less daily) for cardiac prophylaxis allowed.
• Any local skin condition at the treatment sites that in the Investigator's opinion would adversely affect treatment or outcomes.
• Open and/or infected wound in the treatment areas.
• Allergy to lidocaine.
• History of cryoglobulinemia
• History of paroxysmal cold hemoglobinuria.
• History of cold urticaria.
• History of Raynaud's disease.
• History of opioid or alcohol abuse.
• Subject is pregnant or planning to become pregnant while enrolled in the study.
• Current enrollment in any investigational drug or device study or participation within 30 days prior to screening.
• Currently being treated for related knee injury under worker's compensation claim or equivalent (i.e. legal case).
• Any chronic medical condition that in the Investigator's opinion would prevent adequate participation.
• Any chronic medication use (prescription, over-the-counter, etc.) that in the Investigator's opinion would affect study participation or Subject safety.
• For any reason, in the opinion of the Investigator, the Subject may not be a suitable candidate for study participation (i.e., history of noncompliance, drug dependency, etc.).