Suzetrigine in TKA

Numeric Rating Scale in Post-Anesthesia Care Unit (PACU) ranging from average to least to worst. Post operative pain using Numeric Rating Scale(current at rest, with ambulation, worst \& least in last 24 hours). The Numeric Rating Scale is a simple, widely used tool for measuring pain intensity. It consists of a 0-10 point scale. This will be measured after surgery in the PACU.

Numeric Rating Scale measured at 14 days following surgery, then at 6 weeks following surgery and then 12 weeks following surgery. Measurements will range from average pain to worst pain to least amount of pain over the last 7 days and current pain.

Cumulative Opioid consumption (Oral morphine equivalents = OME): Post anesthesia care unit (PACU) at 0 and 24hours, 168 hours, and 14 days (i.e. 7 days postoperatively). The primary outcome is cumulative consumption in oral morphine equivalents starting from entry into the post-anesthesia care unit (PACU). This measure will be taken from EPIC via the MAR and documented in the study "MUD"; post-discharge, patient to report date/time of opioid use # of pills, dose in diary and documented in study "MUD". Measurements will be taken in PACU, 0-24hrs, 0-48 hrs and 0-168hrs following surgery.

Patients that no longer require opioid medications at Postoperative day 2 (48hrs), 7 (168hrs) and 14

If patient is currently taking opioids or getting Opioid prescription refills, answered as either yes or no and assessed on post operative day 14, at week 6 and week 12 following surgery.

Analgesics used other than opioids on day of surgery, postoperative day 2 (i.e. 48 hrs), day 7 (i.e. 168hrs), and day 14

The percentage of patients who patients who stopped taking either the placebo drug or Suzetrigine within the first 14 days following surgery

Number of patients that requested more or a refill of Suzetrigine after the randomization period was over

Patients will communicate there satisfaction with how well their pain is controlled this will be assessed 2 days and 7 days and 14 days following surgery. Number on Scale out of 10 (where 0 is not satisfied, 10 is very satisfied).

Measuring how much since surgery Pain has interfered with normal day to day activities. This will be self reported using a number Scale (0-10, 0= no interference, 10= significant interference) on postoperative days 2 and 7 and 14. Patients will be asked; how much, since your surgery, has pain interfered with performing activities in bed such as turning, sitting up, and changing position? how much, since your surgery, has pain interfered with walking? how much, since your surgery, has pain interfered with your sleep? how much, since your surgery, has pain interfered with your mood?

Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS, JR) is a 0-100 scale that assesses hip pain and function, where a higher score indicates better hip health and a lower score indicates greater disability. This will be assessed preoperatively within 30 days of the surgery and then again 6 weeks post operatively. This measure will be extracted via EPIC or by a patient reported survey if not filled out in EPIC/mychart.

Sleep quality will be assessed using patient-reported questionnaires that evaluate sleep patterns over the preceding week. Assessments will be completed preoperatively and on postoperative days 7 and 14. Outcomes will include overall sleep quality rating and average sleep duration in hours per night.

Unexpected adverse events, that may occur to the patient after administration of Suzetrigine from the date the medication is given to the 14th day following surgery using Common Terminology Criteria for Adverse Events (CTCAE) v6.0 (MedDRA 28.0) grading system

Grade 1 Mild; Grade 2 Moderate; Grade 3 Severe or medically significant; Grade 4 Life-threatening consequences; Grade 5 Death related to AE.

for Nausea, Vomiting, Constipation, Difficulty passing urine, Concentrating, Somnolence, Lightheaded/dizziness, Confusion, Fatigue, Pruritis, Headache, Dry mouth, Paresthesia, Muscle spasm, Rashes, Problems with sleep, Delirium, Abnormal lab values, Other Patient-reported adverse effects (diarrhea, changes to heart beat/arrythmias, blurred vision, low blood pressure, difficulty breathing, hives, swelling of the face/lips/tongue/extremities/throat, other)

Patient expectations regarding the effectiveness of Suzetrigine for postoperative pain management will be assessed prior to surgery using a questionnaire. Patients will report their anticipated level of pain relief, improvement in function, reduction in opioid requirements, and overall confidence in the medication.

Duration of peripheral nerve block will be assessed from the time of block administration until complete resolution of sensory and motor blockade. Resolution will be determined through patient report and clinical assessment of return of normal sensation and motor function.

Knee range of motion (ROM) will be measured at 6 weeks following surgery using standard clinical assessment techniques. ROM will be recorded in degrees and include measurements of both knee flexion and extension. Higher flexion and lower extension deficits indicate improved postoperative joint function.

The rate of manipulation under anesthesia (MUA) performed for postoperative knee stiffness will be recorded through 6 weeks and 12 weeks after surgery. Incidence will be reported as the proportion of patients requiring MUA during the follow-up period.

Sleep duration will be assessed using patient-reported questionnaires that evaluate sleep patterns over the preceding week. Assessments will be completed preoperatively and on postoperative days 7 and 14. Outcomes will include overall sleep quality rating and average sleep duration in hours per night.