Foot and ankle surgery is typically very painful for the first two days postoperatively due to surgical oedema. This pain is difficult to control with systemic analgesics. Pain relief with systemic analgesics requires high doses of intravenous opioids and is associated with breakthrough pain and adverse effects of opioids (sedation, nausea, vomiting, obstipation, urinary retention, mouth dryness, respiratory depression, pruritus, vertigo and visual disturbances).