TOPLINE:

Patients who underwent lower limb orthopedic surgery and received a single-shot femoral nerve block had an increased risk for falls during the early postoperative period.

METHODOLOGY:

• Researchers conducted a systematic review and meta-analysis of 34 randomized controlled trials to assess the risk for falls after receiving a single-shot femoral nerve block.
• The analysis included adults and children (mean age range in the studies, 26.0-70.8 years; 14.3%-81.3% female) who underwent lower limb orthopedic surgery.
• Patients received a single-shot femoral nerve block in the femoral triangle, either alone or as part of a three-in-one block. The block was administered within 1 hour before the initiation of anesthesia or 1 hour after surgery ended.
• They were compared with those who received systemic analgesia, neuraxial blockade, local anesthetic infiltration, motor-sparing peripheral nerve blocks, or no blocks/sham blocks.
• The primary outcome was the incidence of falls per participant within 96 hours of the end of surgery; secondary outcomes were the incidence of predictors of falls, such as buckling and near-falls.

TAKEAWAY:

• Recipients of a single-shot femoral nerve block had a significant increase in fall events compared with those who received an adductor canal block (risk ratio [RR], 4.39; 95% CI, 1.30-14.83; 11 studies), neuraxial blockade (RR, 6.35; 95% CI, 1.16-34.82; six studies), or systemic analgesia (RR, 6.43; 95% CI, 1.19-34.80; six studies).
• The use of a single-shot femoral nerve block was associated with an increased risk for falls compared with the use of nonmotor block techniques (RR, 2.75; 95% CI, 1.19-6.34).
• Both low-risk and non-low-risk trials demonstrated an increase in the risk for falls after the use of a single-shot femoral nerve block (RR, 4.78; 95% CI, 1.66-13.72 and RR, 2.96; 95% CI, 1.20-7.29, respectively).

IN PRACTICE:

“[A]longside the numerous potential benefits, certain forms of [peripheral nerve blocks] may also have detrimental effects,” the researchers reported. “A brief discussion of leg weakness alone, without a full disclosure of the potential repercussion of falling after” a single-shot femoral nerve block, is insufficient, they added.

SOURCE:

The study was led by Matthew J. Billingham, of University Hospitals Coventry and Warwickshire NHS Trust in Coventry, England. It was published online on December 31, 2025, in the British Journal of Anaesthesia.

LIMITATIONS:

The sample size in individual trials was small, with most having fewer than 100 participants per group. The focus on the analgesic effects of single-shot femoral nerve block may have led to less thorough reporting of fall outcomes. The study faced challenges in assessing the experience level of those administering the single-shot femoral nerve block, which may affect the applicability of the findings.

DISCLOSURES:

This study did not receive any financial support. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.