for people ages 18-45 (full criteria)
at Sacramento, California
study started
completion around
Principal Investigator
by Cassandra Lee, MD



This study will compare the outcome of pain interventions that are considered standard of care during the surgical treatment of ACL injuries. The comparison will be looking at pain control during and after ACL surgery as well as functional outcomes in patients that had a nerve block versus those who did not. The investigators hypothesize that pain control will be equal between both groups.

Official Title

Pain Management of Anterior Cruciate Ligament Reconstruction: Evaluation of Adductor Canal Block Versus Oral Pain Regimen


Specific Aim #1: To determine if there is a difference in opioid pain medication use following anterior cruciate ligament (ACL) reconstruction between an oral pain regimen versus adductor canal block.

Specific Aim #2: To determine if there is a difference in knee recovery and function post-operatively following ACL reconstruction between an oral pain regimen versus adductor canal block.

Specific Aim #3: To determine if cost-effectiveness or patient flow logistics of ACL reconstruction are affected by whether has patient has adductor canal block versus receiving oral pain medication regimen.

Specific Aim #4: To determine if pre-operative Resiliency scores are associated with post-operative pain and outcomes following ACL reconstruction.

Hypothesis #1: There is no difference in post-operative pain management or functional outcomes following ACL reconstruction based on whether patient had adductor canal block versus an oral pain medication regiment implemented.

Hypothesis #2: Worse resiliency scores pre-operatively are associated with worse outcomes and pain scores post-operatively following ACL reconstruction.

Upon enrollment and at at the participant's pre-op appointment, the participant will complete a questionnaire entitled the Brief Resiliency Scale (BRS) to determine the participant's resiliency score and receive post-operative pain medication prescriptions. At time of surgery the participant will begin a pain diary to chronicle use of pain medication for 6 weeks and turn this document in at the 6-week follow-up appointment along with documentation of time to first able to walk (ambulate) without assistive device (i.e. crutch, walker, etc.). In the recovery room, the participant will verbally complete a Visual Analog Scale to determine the pain level at 15 minutes after surgery and before discharge. At the 3-month post-op visit, the participant will complete another questionnaire entitled the Knee Injury and Osteoarthritis Outcome Score (KOOS) to determine operative knee pain and function. At the 6-month post-op visit, the participant will complete a questionnaire entitled Marx Activity Rating Scale to determine operative knee function.

The treatment will be chosen by chance, like flipping a coin. Neither the participant nor the study doctor will choose what treatment the participant receives. The participant will have a one in two chance of being given each treatment. The participant will know which treatment was given but the operating surgeon will not know.

The participant will be randomized to 1 of 2 standard of care treatment groups at the time of surgery:

  • Adductor canal nerve block (an anesthetic block of the femoral nerve halfway down the thigh that causes numbness in the knee and lower part of the leg)), or
  • No nerve block for perioperative (during the operation) pain control.

Regardless of treatment group, all participants pre-operatively will receive the following pain medication: 400 mg celecoxib (Celebrex), 300 mg gabapentin (Neurontin), and 1 g of acetaminophen (Tylenol) 1-2 hours before surgery. This oral regimen is similar to standard of care pre-operative medication in total knee arthroplasties (knee replacements).

All participants will also receive the same post-operative prescriptions at their pre-operative clinic visit which will be: 90 tablets of 1 g acetaminophen to be taken three times a day for 30 days and 90 tablets of 5 mg oxycodone with 1-2 tablets to be taken every 4 to 6 hours as needed for pain. Additionally, the participant will receive two medications (Zofran, Phenergan) for nausea/vomiting which are to be taken as needed. Participants will record their medication use.

ACL reconstruction and any other procedures to address any other damage in the participants's knee as determined by the surgeon will be performed as per standard clinical practice at an outpatient surgical facility. The participant will undergo standard post-operative rehabilitation. During the standard of care post-operative visits in the Sports Medicine Clinic, the participant will be asked to fill out questionnaires specific for our data collection.


Anterior Cruciate Ligament Rupture, ACL, Rupture, Ropivacaine, Adductor Canal Nerve Block, Ropivacaine injection


You can join if…

Open to people ages 18-45

  • Between the ages of 18 and 45 years old.
  • Clinical and/or advanced imaging confirmation of ACL tear of which reconstructive surgery is recommended and accepted.

You CAN'T join if...

  • No prior surgery of the affected and contralateral knee
  • Adults unable to consent
  • Children (age < 18 years old)
  • Prisoners
  • Pregnant women
  • Inflammatory arthritis
  • Non-English-speaking patients


  • UC Davis Health
    Sacramento California 95817 United States

Lead Scientist at UC Davis

  • Cassandra Lee, MD
    Associate Professor, Orthopaedic Surgery, School of Medicine. Authored (or co-authored) 41 research publications


accepting new patients
Start Date
Completion Date
University of California, Davis
Learn more or sign up for the study here! Sign up for this study
Study Type
Expecting 60 study participants
Last Updated