Lost interest in study

The purpose of this study is to assess the potential benefit of preoperative cryoneurolysis in postoperative pain management of total knee arthroplasty patients over current pain management protocol.

Cryoneurolysis, is a novel technique that can yield temporary blockade of superficial sensory nerves, generating immediate and meaningful relief of pain.The technique generates an axonotmesis of the targeted peripheral nerves by percutaneously applying low temperatures (-100 °C to -20 °C). Wallerian degeneration is produced whereby the axons and the myelin sheath are damaged but the endoneurium, perineurium and epineurium remain intact. Therefore, permanent damage to the nerve is avoided as it retains its regenerative properties. With regards to the knee, the infrapatellar branch of the saphenous nerve (IPBSN), a sensory branch serving both the inferior and anterior portion of the knee capsule and the antero-medial skin of the knee is the prime target for the procedure.

Your participation in this study requires that you allow the radiology department of Texas Orthopedic Hospital to administer Cryoneurolysis using the Iovera device with the functional smart tip approximately 1 week prior to total knee arthroplasty surgery. A highly localized cold zone is created via the Joule-Thompson effect as nitrous oxide enters the needles. Nothing is injected into the body and the nitrous oxide gas is vented safely out of the handpiece. Cryoneurolysis is administered following local anesthesia.

Inclusion Criteria:

• any patient scheduled for primary total knee arthroplasty(TKA)

Exclusion Criteria:

• Bilateral TKA (patients routinely receive spinal anesthesia)
• Minors
• Patients reporting a history of Raynaud's disease
• Patients with an open and/or infected wound on surgical knee
• Patients who are taking opioids during the pre-operative period due to knee pain
• Patients who cannot return for the cryoneurolysis treatment 7 days prior to surgery or post-operative clinical visits
• Patients whose insurance would deny payment for the cryoneurolysis treatment
• Pregnant patients
• Patients unable to speak and read English