Study Supports Use of a Continuous Nerve Block for Patients Receiving ACL Repair Surgery

A study out of Stanford University has found that use of a femoral catheter in patients undergoing anterior cruciate ligament (ACL) reconstructive surgery is associated with better results. Specifically, patients receiving the treatment had lower opioid consumption and a small improvement in continuous passive motion (CPM) device use.

The ACL is a ligament in the knee, and younger patients in particular are often referred for surgery when the ligament is torn. Maintaining quadriceps muscle strength and mobility after surgery is important when patients receive surgery to a leg to aid in a quicker recovery. For this reason, doctors commonly have been using a nerve block called the adductor canal block (ACB), which is considered a better choice than a femoral nerve block (FNB) because it spares the quadriceps muscles.

With ACL surgery, though, patients are actually instructed to not put their weight on the affected leg immediately after surgery. This lowers the benefit of the ACB in this specific surgery. While past studies have compared single-injection techniques, the Stanford researchers hypothesized that using a continuous FNB would provide better pain control without sacrificing the advantages of sparing the quadriceps muscles.

Instead of receiving a single injection, patients received a standard ultrasound-guided femoral or adductor canal block catheter prior to surgery. They received a loading dose of medication prior to their operations, followed by continuous infusion after the procedures. In follow-up interviews, patients were asked about pain scores, opioid usage, catheter demand bolus dosage, and use of the CPM devices, which indicates their levels of engagement in rehabilitation.

The study found that the patients who received the FNB consumed less opioids and were able to use the CPM more. The researchers recommend further studies to confirm the long-term effectiveness of FNB on ACL surgery patients.

The abstract was chosen for one of three Resident/Fellow Travel Awards. Justin Chen will present the findings on Friday, March 22, at 8 am PT, during the 49^th Annual Regional Anesthesiology and Acute Pain Medicine Meeting in San Diego, CA. Coauthors are Drs. Ksenia Kasimova, Audrey Horn, Ban Tsui, and Jean-Louis Horn.

ASRA Pain Medicine is a membership society of more than 5,000 health care professionals devoted to advancing evidence-based practice of pain medicine across the pain continuum, from acute pain to chronic pain. Our mission is to advance the science and practice of regional anesthesia and pain medicine to improve patient outcomes through research, education, and advocacy. Our vision is to relieve the global burden of pain. We are committed to integrity, innovation, inclusiveness, service, compassion, and wellness. Learn more at www.asra.com.