Characteristics of calcaneal osteomyelitis: An unusual and severe form of diabetic foot disease

Abstract

Background: Osteomyelitis of the calcaneus is an uncommon type of diabetic foot infection considered to have a poor outcome. Little is known about predisposing and prognostic factors, or optimum treatment regimens. Methods: Case records were reviewed of the eight patients with diabetes who presented to our centre during 2011-13 with calcaneal osteomyelitis and a complementary group of 19 patients who presented with heel ulcers but without osteomyelitis. Results: Male sex (6/8 vs. 4/19; p<0.05), peripheral neuropathy (8/8 vs. 4/19; p<0.001), ulcer size >2 cm2 (8/8 vs. 3/19; p<0.0001) and depth (probing to bone) (6/8 vs. 0/19; p<0.0001) were associated with calcaneal osteomyelitis. We were unable to identify any patient or treatment characteristics in the osteomyelitis group that conferred improved outcome. Outcomes at 30 weeks after presentation were significantly poorer in the osteomyelitis group (ongoing osteomyelitis or amputation 4/8, and death 2/8) than in the ulcer only group (1/19 and 2/19). Conclusions: In patients with diabetes and heel ulcers, calcaneal osteomyelitis is associated with male gender, neuropathy and large deep ulcers. It is uncommon and has a poor prognosis. We were unable to identify any factors associated with improved prognosis.