Study: Femoral Nerve Block in ACL Surgery May Cause Complications

February 22, 2018

DETROIT – A Henry Ford Hospital study has found that a nerve injection commonly used for pain control during knee reconstruction surgery is associated with complications in high school and collegiate athletes.

The study, published in the Journal of Arthroscopic and Related Surgery, is the latest to compare the effectiveness of a femoral nerve block and an alternative pain control method called local infiltration anesthesia (LIA).

Prior research has linked the nerve block with postoperative sensation complications and weakness in the quadriceps, which could cause the repaired knee to give way or buckle and lead to a fall or injury.

Researchers found that even if a patient experienced a nerve complication, it did not cause permanent knee weakness 10 months after surgery, says Kelechi Okoroha, M.D., chief resident in the Department of Orthopedic Surgery at Henry Ford and the study’s lead author.

Although all patients with complications after femoral nerve block were found to recover, a significant amount of patients in both study groups had not fully regained knee strength and function to return to sport after the typical nine months of recovery and rehab, Dr. Okoroha says.

“The fact that full strength and function are not achieved in many patients at the normal return to sport time frame, it raises a caution flag and it would be best to allow the knee more time to fully heal before the athlete returns to play,” Dr. Okoroha says. “Physicians should monitor strength and function in athletes after knee reconstruction as returning to play too quickly could lead to reinjury.”

In the small randomized study of 44 high school and collegiate athletes, 23 received the nerve block and 21 receive the LIA during ACL reconstruction surgery between December 2014 and July 2015. During at least three months of rehab, they were put through a series of flexibility movements to test their knee function and strength, including a single-leg hop and single-leg triple crossover. After nine months, researchers assessed data on the athletes’ knee strength and function. Strength and function complications of 15 percent and 10 percent, respectively, are considered clinically significant, based on prior research.

The study was funded by Henry Ford Hospital.


David Olejarz