BedBiopsy: Diagnostic performance of bedside ultrasound-guided bone biopsies for the management of diabetic foot infection

Objective: We aimed to assess the feasibility and diagnostic performance of ultrasound-guided bone biopsies at the bedside of diabetic patients admitted for suspected foot osteitis not requiring surgery.

Research design and methods: In this retrospective monocentric study, we compared the performance of ultrasound-guided (n = 29 consecutive patients, Dec.2020-Oct.2022) versus surgical (n = 24 consecutive patients, Jan.2018-Nov.2020) bone biopsies at confirming or ruling out diabetic foot osteitis (primary outcome).

Results: Patient characteristics were similar in the two intervention groups, including arteritis prevalence (62.3 %), SINBAD score, and wound location (phalanges 36 %, metatarsus 43 %, and calcaneus 21 %). However, the ultrasound-guided group was older (67 ± 11 versus 60 ± 13 years respectively, P = 0.047) and had more type 2 diabetes (97 % versus 75 %, P = 0.038). Diagnostic performance (i.e., capacity to confirm or rule out suspected osteitis) was similar for ultrasound-guided (28/29 cases: 25 confirmations, 3 invalidations) and surgical (24 confirmations/24) biopsies, P = 0.358. No biopsy-related side effect or complication was observed for either intervention, even for patients on antiaggregation and/or anticoagulation therapy. The mean (± standard deviation) time necessary to perform the biopsy was shorter in the ultrasound-guided group (2.6 ± 3.0 versus 7.2 ± 5.8 days, respectively, P < 0.001) and wound evolution at three months was more favorable (83.3 versus 41.2 %, P = 0.005) (94.4 % versus 66.7 %, respectively, patients with new surgical procedure within six months excluded; P = 0.055). Even though not statistically significant, healing rates in terms of wound and osteitis at six months were also better in the ultrasound-guided group (wound: 40.9 % versus 36.8 %; P = 0.790, and osteitis: 81.8 vs 55.6 % P = 0.071).

Conclusion: In diabetic patients with suspected foot osteitis not requiring surgery, bedside ultrasound-guided bone biopsies may constitute a promising alternative to surgical biopsies. This intervention provided excellent tolerance and microbiological documentation, short lead-times, and more favorable wound prognosis.