PLACEMENT is a phase III, pragmatic, open-label, two-arm, individually randomised controlled trial, comparing perineural catheter (PNC) and local anaesthetic infusion for the first five postoperative days after major lower limb amputation (MLLA) with no PNC.

Major lower limb amputations are life changing events, associated with both immediate postoperative pain and long term pain. Pain may delay recovery, including phantom limb pain, which may interfere with fitting and using an artificial leg. Morphine is often used to help with postoperative pain. However, morphine has major side effects, including sickness, confusion, and breathing problems.

PLACEMENT aims to test a method for reducing pain after leg amputation. It involves the surgeon placing a small catheter (PNC) next to the main nerve which is cut during surgery. Local anaesthetic is delivered via the PNC for five days, which may replace some, or all, of the morphine needed. PNC use may also reduce phantom limb pain. PLACEMENT will compare pain in participants who had the PNC to those who did not, to find out if one method results in less post-operative pain than the other.

The primary outcome measure is ‘Freedom from pain,’ defined as the proportion of time points with self-reported pain ≤3 on a 0 to 10 numeric rating scale (NRS). Secondary objectives are to evaluate the effect of PNC use on participant satisfaction of pain management; total opioid use; opioid side effects and postoperative complications during the first 5 postoperative days, and longer-term outcomes on pain, wound healing, residual limb surgery; health-related quality of life; healthcare resource use; cost; ambulation rates and mortality.

Patients undergoing a primary above/below/through knee amputation for complications of peripheral arterial disease and/or diabetes, aged 18 years and over, with a life expectancy of greater than 2 weeks, who are able to consent and assess pain using a numeric rating scale (NRS) are eligible for inclusion. Patients who are undergoing simultaneous bilateral amputations; allergic or intolerant to the perineural catheter (PNC) or local anaesthetic; chronically taking class 1B antiarrhythmic agents or local anaesthetic; expected to be sedated for more than 24 hours postoperatively; vulnerable, protected or pregnant are excluded from participating.

The planned sample size is 650 participants. PLACEMENT will be conducted at 14 NHS sites across the UK. Participants will be involved in the trial for 6 months. They will fill out twice daily pain scores for the first 5 postoperative days, and additional pain scores and quality of life questionnaires at 3 and 6 months.