Study: Femoral nerve blockade leads to poor isokinetic quadriceps strength after ACL reconstruction

SAN ANTONIO — Patients who underwent ACL reconstruction with bone-tendon-bone autograft with a continuous femoral nerve blockade have inferior isokinetic quadriceps strength after 6 months compared to patients who did not receive a continuous femoral nerve blockade, according to a presenter at the Arthroscopy Association of North America Annual Meeting, here.

“Our data showed that continuous femoral nerve blockade showed an inferior isokinetic quadriceps strength at 6 months,” Scott Kuzma, BS, said. “Despite these findings, however, no differences were observed in return to sport.”

In this retrospective study, researchers compared 104 patients who underwent ACL reconstruction with bone-tendon-bone autograft and received continuous femoral nerve blockade (FNB) against a control group of 104 patients who received no FNB between 2004 and 2010. Both groups underwent similar rehabilitation protocols. After 6 months, the researchers compared isokinetic strength data between groups and used a regression model to compare quadriceps strength.

The investigators concluded fast quadriceps isokinetic strength was 77% in the FNB group vs. 85% in the control group. Slow quad isokinetic strength was 71% in the FNB group compared to 76% in the control group, however, this percentage did not reach statistical significance according to Kuzma. After adjustment for gender, researchers concluded that fast and slow quad strength were worse in the FNB group.

“This is the first comparative study that objectively assessed quadriceps strength and function following ACL reconstruction with a femoral nerve blockade,” Kuzma said.

Reference:

Kuzma S. Paper #SS-13. Presented at: Arthroscopy Association of North America Annual Meeting; April 25-27, 2013; San Antonio.

Disclosure: Kuzma has no relevant financial disclosures.