Management of osteomyelitis of the diabetic foot using highly purified calcium sulphate impregnated with antibiotics: a 2 year follow up

R. Jogia, D.E. Modha, M.-F. Kong, R. Berrington

Aim: Osteomyelitis is a challenging complication of the diabetic foot with prevalence of up to 20% of infected ulcers. This may lead to a greater incidence of amputations. Whilst 70-80% of osteomyelitis can be managed with systemic antibiotics alone surgery is indicated for those in whom this fails. Traditionally, surgery involves debriding to healthy bone, leaving the wound open for drainage. This often leaves severe tissue loss. There are many local antibiotic delivery products used in adjunction to surgery.
The aim our study was to look at outcomes over a 2 years follow up of 109 diabetic patients who underwent surgery using highly purified calcium sulphate/ antibiotics as an adjunct.

Method: 109 patients were reviewed who had undergone day case surgery from March 2013 to February 2016. Conservative management with off-loading and systemic antibiotics were tried. All patients had neuropathy and their circulation deemed to be adequate. Osteomyelitis was diagnosed using imaging and/or microbiology. All patients underwent debridement of the ulcer and bone sequestra. Remaining bone was packed with highly purified calcium sulphate impregnated with Vancomycin 1g and Gentamicin 80mg. Intra operative bone samples were sent to microbiology. Primary closure was carried out where possible.

Results: Median duration of ulcer pre-operatively 17 weeks. Duration of pre-operative systemic antibiotics 8 weeks. Healing time post operatively 6 weeks. Duration of antibiotics post operatively 1.4 weeks. No complications / adverse events noted.

Discussion: Results show effectiveness of this treatment modality for management of osteomyelitis. The authors acknowledge limitations of this case series and would recommend a prospective multi-centre randomised control trial.

Conclusion: Our experience using this technique has changed the way we manage our patients. We offer this much earlier in the patient's management particularly where the wound is deteriorating despite being on appropriate antibiotics. We have reduced the duration of systemic antibiotics.