Total hip replacement is a major surgical procedure usually associated with significant pain in the early postoperative period. In our hospital, total hip replacement is routinely performed under spinal anaesthesia with intrathecal bupivacaine local anaesthetic plus opioid in the form of preservative free morphine. The use of 'local infiltration analgesia' as an alternative postoperative analgesic technique has been investigated.In this technique the surgeon infiltrates the surgical site with a long-acting local anaesthetic and places a catheter under direct vision which remains in situ and is used to administer local anaesthetic in the postoperative period until such time as it is removed (when no longer deemed necessary for pain relief or at a pre-set time in the postoperative period e.g. 48 hours). We hypothesize that infiltration of the surgical site with peri- and intraarticular levobupivacaine local anaesthetic would be an efficacious pain management technique and would not be inferior to intrathecal morphine for postoperative pain management.

Inclusion Criteria:

• Patients scheduled for unilateral total hip replacement
• Consent to spinal anaesthesia
• ASA Grade I to III

Exclusion Criteria:

• Patient refusal
• Mini-Mental Score < 25
• Allergy to bupivacaine, morphine, paracetamol, diclofenac
• Skin lesions/infection at site of injection
• Uncorrected renal dysfunction
• Coagulation disorders
• chronic pain condition other than hip pain