The Effects of Timing of Ankle Blocks in Forefoot, Midfoot, or Hindfoot Reconstruction With the Use of an Ankle Tourniquet

Background: Ankle blocks are used in the ambulatory surgery setting to control postoperative pain, which is often worst in the first 24 hours after surgery. We conducted a trial to determine whether the timing of ankle block administration in relation to ankle tourniquet inflation has an effect on perceived pain and narcotic consumption.

Methods: A prospective randomized study was conducted between August 2015 and January 2016. Patients were assigned to three groups. In group A, an ankle block was performed before ankle tourniquet inflation; in group B, immediately after ankle tourniquet inflation; and in group C, immediately after ankle tourniquet inflation with additional local anesthetic placed around the incision at the end of the procedure. Pain was assessed by a visual analogue scale (VAS) score, which was recorded at discharge, 24 hours, 48 hours, and 2 weeks after surgery. Narcotic consumption was recorded at 24 and 48 hours after surgery.

Results: The only statistically significant difference in mean VAS scores occurred at 24 hours, when patients who received an ankle block after tourniquet inflation with local incisional anesthetic at closure (group C) had a mean VAS score 2.8 points lower (3.5 vs 6.3; P = .025) than those who received only an ankle block after tourniquet inflation (group B). There was no difference in narcotic consumption between groups at 24 and 48 hours.

Conclusions: The timing of ankle block in relation to tourniquet inflation did not have an effect on pain control in forefoot, midfoot, and hindfoot reconstruction. The synergistic effect of an ankle block with additional incisional anesthetic at closure, is more effective than ankle block alone and is the ideal combination for postoperative pain control in foot surgery.

Levels of evidence: Therapeutic, Level II: Prospective, comparative trial.