The Use of Calcium Sulphate as a Drug Delivery System in Lower Limb Amputation

Background Amputation in the lower limb can be a challenging procedure both for the surgeon and the patient. Common complications include revision of amputation and wound infection, increasing morbidity to patients and putting further pressure on stretched health services. We describe a simple technique used in lower limb amputation using an antibiotic-loaded calcium sulphate bone graft placed in the medullary canal and soft tissues to control haemostasis and deliver a high dose of antibiotics locally into the wound bed. Methodology We describe a series of 17 lower limb amputations in 15 patients from our unit between 2014 and 2021. Infection was eradicated through aggressive debridement of the infected bone and soft tissues. An antibiotic-loaded calcium sulphate bone graft was placed into the medullary canal, along with pellets into the soft tissues. Wounds were either closed primarily or left open to heal by secondary intention due to skin loss following debridement. Our primary outcome measure was the need for amputation revision to a more proximal level during the acute treatment phase (six weeks). Results Indication for amputation in most cases was osteomyelitis. Operations included below-knee, transmetatarsal, and ray amputations. In this 17-procedure series, no patients required revision of amputation to a more proximal level in the acute treatment phase using this technique. Overall, there were three incidences of wound infection (17.7%). Conclusions Placing calcium sulphate beads loaded with antibiotics into the medullary canal and surrounding tissues is a simple adjunct in lower limb amputation, aiming to reduce rates of wound infection and amputation revision. Comparing this cohort to previous literature is challenging due to mixed indications and levels of amputation. However, the outcomes described aid the pragmatic decision-making in a complex patient group.