Post-Operative Pain Relief: Zynrelef or Periarticular Injections in RATKA

Official title

Postoperative Pain Outcomes After Use of Bupivacaine-Meloxicam Extended-Release Solution in Robot Assisted Total Knee Arthroplasty: A Prospective Study

Overview

Prospective Cohort of patients who are scheduled for a Robot Assisted Total Knee Arthroplasty (RATKA). A prospective survey of patient reported outcome measures (Numeric Rating Scale) will be obtained postoperatively of 72 hours, as well as at the postoperative opioid consumption after 72 hours.

Detailed description

Opioid use is a well-discussed issue in the United States among orthopedic surgeons, as while these drugs are helpful and necessary, they pose the risk of addiction and ultimately should be used as sparingly as possible. By taking a multimodal approach to pain management, this can be successfully achieved. Periarticular injections are currently used to achieve this goal, and 2021 a bupivacaine-meloxicam extended-release periarticular injection (Zynrelef) was introduced and is regularly implemented into RATKAs. Randomized clinical trials found that Zynrelef's use in traditional total knee arthroplasties (TKA) was just as effective as standard periarticular injections in reducing opioid use and pain, but whether Zynrelef works just as well if not better in RATKA is not yet established.

Objectives: (primary and important secondary objectives)

To evaluate the improvement in pain and use of opioids of a patient who received Zynrelef after undergoing RATKA compared to the traditional periarticular injections commonly used. The secondary objective will be documentation of the patient's use of other oral (over-the-counter) OTC pain relievers, such as acetaminophen or NSAIDs (non-steroidal anti inflammatory drugs).

Study Design:

Prospective Cohort Study (double arm)

Setting/Participants:

Patients who have undergone a standard of care RATKA at any Allegheny Health Network facility who consent to filling out a survey addressing their reported outcomes.

Study Interventions and Measures:

Patients will be evaluated with the Numeric Rating Scale (NRS) on postoperative days 1-3. Patients will be given paper forms which will be collected by the physicians at their next postoperative visit. A retrospective review of Epic Electronic Medical Records (EMR) will also be conducted to describe basic demographic characteristics.

Interventions

• Combination product bupivacaine-meloxicam (extended release)
  These surgeons will be using Zynrelef (bupivacaine-meloxicam extended release) as a form of periarticular analgesia.
• Drug Bupivacaine
  These surgeons will be using the control injection (bupivacaine + ketorolac + lidocaine) as a form of periarticular analgesia.
• Drug Ketorolac
  These surgeons will be using the control injection (bupivacaine + ketorolac + lidocaine) as a form of periarticular analgesia.
• Drug Lidocaine (drug)
  These surgeons will be using the control injection (bupivacaine + ketorolac + lidocaine) as a form of periarticular analgesia.

Primary outcome measures

• Amount of opioid medications used (measured in morphine milligrams equivalents) [Time frame: From completion of surgery to 3 days post-op]
• Patient reported outcome measure (Numeric Rating Scale) [Time frame: From completion of surgery to 3 days post-op]

Secondary outcome measures (2)

• Amount of oral Over-the-counter (OTC) pain reliever medications used [Time frame: From completion of surgery to 3 days post-operation]
• Complications and Adverse Events [Time frame: From completion of surgery to 3 days post-op]

Eligibility criteria

Inclusion criteria

Males or females aged 18-89 years

Diagnosed with knee osteoarthritis requiring surgical intervention

Indicated for unilateral RATKA

Exclusion criteria

Pediatric, pregnant, or incarcerated patients

BMI of more than 45 kg/m2

Prolonged opioid use history of >5 mg/day for >1 month

History of contralateral TKA <2 years prior to the index TKA

Type 1 Hypersensitivity to NSAIDs or local anesthetics

Diagnosis of severe renal disease

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Treatment

Study locations

Center list to be confirmed — check the primary protocol.

Publications

• Joo PY, Chen AF, Richards J, Law TY, Taylor K, Marchand K, Clark G, Collopy D, Marchand RC, Roche M, Mont MA, Malkani AL. Clinical results and patient-reported outcomes following robotic-assisted primary total knee arthroplasty : a multicentre study. Bone Jt Open. 2022 Aug;3(8):589-595. doi: 10.1302/2633-1462.37.BJO-2022-0076.R1. PMID 35848995
• Salmons HI, Amundson AW, Duncan CM, Larson DR, Mallinger BD, Couch CG, Pagnano MW, Trousdale RT, Abdel MP. Bupivacaine-Meloxicam Extended-Release Solution Compared with a Standard Periarticular Injection in Primary Total Knee Arthroplasty: A Randomized Clinical Trial Showing Similar Efficacy in Postoperative Analgesia. J Bone Joint Surg Am. 2025 Jul 25;107(17):1918-1925. doi: 10.2106/JBJS.25.00086 PMID 40711999
• Blair HA. Bupivacaine/Meloxicam Prolonged Release: A Review in Postoperative Pain. Drugs. 2021 Jul;81(10):1203-1211. doi: 10.1007/s40265-021-01551-9. Epub 2021 Jul 6. PMID 34228280
• Dydyk AM, Jain NK, Gupta M. Opioid Use Disorder: Evaluation and Management. [Updated 2024 Jan 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-.
• Cui A, Li H, Wang D, Zhong J, Chen Y, Lu H. Global, regional prevalence, incidence and risk factors of knee osteoarthritis in population-based studies. EClinicalMedicine. 2020 Nov 26;29-30:100587. doi: 10.1016/j.eclinm.2020.100587. eCollection 2020 Dec. PMID 34505846

Identifiers

NCT: NCT07430085 · 2025-344

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗