Ankle block in forefoot reconstruction before or after inflation of tourniquet--Does timing matter?

BACKGROUND: Forefoot surgery causes postoperative pain frequently requiring strong painkillers. Regional blocks are now increasingly used in order to control postoperative pain especially in the first 24h when the pain is at its worst. We conducted a prospective study to see if timing of ankle block i.e. before or after inflation of tourniquet showed any difference in efficacy in postoperative pain control in first 24h.

METHODS: A prospective randomised study was conducted between September 2010 and August 2011 involving 60 patients. Group A (n=30) had the ankle block administered after and Group B (n=30) had a block before inflation of a thigh tourniquet. Patients were given assessment forms to chart their pain on visual analogue scale (VAS) score at 4h and 24h postoperatively.

RESULTS: Both groups demonstrated good postoperative pain control. Average VAS pain score at four and twenty fours after surgery was 2.5 and 4.5 in Group A and 3.9 and 6.3 in Group B respectively. Pain control, both at 4 and 24h surgery was better in Group A but this was statistically significant only at 24h.

CONCLUSIONS: A regional anaesthetic ankle block should be routinely used in forefoot surgery to control postoperative pain. The ankle block should be applied after the inflation of tourniquet as this appears to provide better pain control.