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Updated: Aug 18, 2026

Electrophysiological Methods to Assess Peripheral Pain Block in an Anesthetized Rat
Published on: November 21, 2025
Posterior labat vs. lateral popliteal sciatic block: posterior sciatic block has quicker onset and shorter duration
R Fournier1, A Weber, Z Gamulin
1Department of Anaesthesiology, University Hospital of Geneva, CH-1211 Geneva 14, Switzerland. Roxana.Fournier@hcuge.ch
Background:
During foot and ankle surgery, a combination of a sciatic and femoral nerve block is a well-recognized technique for providing anaesthesia and post-operative analgesia. Our hypothesis is that the posterior gluteal sciatic block (PSB) is more efficient than the lateral popliteal sciatic block (LPSB), and this study compared the anaesthetic characteristics between these two techniques performed for elective ankle and foot surgery.
Methods:
This retrospective database analysis reviewed the onset, duration of action, success rate and complications among 287 patients who were operated upon using sciatic block. PSB was performed in 149 patients and LPSB in 138 patients, all with the use of 30 ml of 5 mg/ml ropivacaine (150 mg).
Results:
In the PSB group, the time to perform the block was shorter than in the LPSB group (2.5 +/- 1 vs. 4.5 +/- 4 min, P < 0.001), as was the time to complete sensory block (13 +/- 13 vs. 23 +/- 26 min, respectively; P < 0.001). However, the duration of sensory block was longer in the LPSB group (1130 +/- 470 vs. 960 +/- 310 min, respectively; P < 0.006).
Conclusion:
PSB is easier to perform, and has a quicker onset of sensory blockade whereas LPSB has a longer duration of analgesia.
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