Diagnostic and therapeutic update on diabetic foot osteomyelitis

Diagnostic imaging of the diabetic foot: an EANM evidence-based guidance

PURPOSE

Consensus on the choice of the most accurate imaging strategy in diabetic foot infective and non-infective complications is still lacking. This document provides evidence-based recommendations, aiming at defining which imaging modality should be preferred in different clinical settings.

METHODS

This working group includes 8 nuclear medicine physicians appointed by the European Association of Nuclear Medicine (EANM), 3 radiologists and 3 clinicians (one diabetologist, one podiatrist and one infectious diseases specialist) selected for their expertise in diabetic foot. The latter members formulated some clinical questions that are not completely covered by current guidelines. These questions were converted into statements and addressed through a systematic analysis of available literature by using the PICO (Population/Problem-Intervention/Indicator-Comparator-Outcome) strategy. Each consensus statement was scored for level of evidence and for recommendation grade, according to the Oxford Centre for Evidence-Based Medicine (OCEBM) criteria.

RESULTS

Nine clinical questions were formulated by clinicians and used to provide 7 evidence-based recommendations: (1) A patient with a positive probe-to-bone test, positive plain X-rays and elevated ESR should be treated for presumptive osteomyelitis (OM). (2) Advanced imaging with MRI and WBC scintigraphy, or [18F]FDG PET/CT, should be considered when it is needed to better evaluate the location, extent or severity of the infection, in order to plan more tailored treatment. (3) In a patient with suspected OM, positive PTB test but negative plain X-rays, advanced imaging with MRI or WBC scintigraphy + SPECT/CT, or with [18F]FDG PET/CT, is needed to accurately assess the extent of the infection. (4) There are no evidence-based data to definitively prefer one imaging modality over the others for detecting OM or STI in fore- mid- and hind-foot. MRI is generally the first advanced imaging modality to be performed. In case of equivocal results, radiolabelled WBC imaging or [18F]FDG PET/CT should be used to detect OM or STI. (5) MRI is the method of choice for diagnosing or excluding Charcot neuro-osteoarthropathy; [18F]FDG PET/CT can be used as an alternative. (6) If assessing whether a patient with a Charcot foot has a superimposed infection, however, WBC scintigraphy may be more accurate than [18F]FDG PET/CT in differentiating OM from Charcot arthropathy. (7) Whenever possible, microbiological or histological assessment should be performed to confirm the diagnosis. (8) Consider appealing to an additional imaging modality in a patient with persisting clinical suspicion of infection, but negative imaging.

CONCLUSION

These practical recommendations highlight, and should assist clinicians in understanding, the role of imaging in the diagnostic workup of diabetic foot complications.

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.

Diabetic Foot Osteomyelitis: Is it all the Same?

Diabetic foot osteomyelitis (OM) requires a longer duration of therapy, a greater need for surgery and implies a higher rate of recidivism, a higher amputation risk, and lower treatment success. But do all bone infections behave the same way, require the same treatment, or imply the same prognosis? Actually, in clinical practice we can verify there are different clinical presentations of OM. The first one is that associated with the infected diabetic foot attack. It requires urgent surgery and debridement since "time is tissue." Clinical features and radiographs are enough for the diagnosis, and treatment should not be delayed. The second one is related to a sausage toe. It affects phalanges and it can be treated with a 6- or 8-week antibiotic course with a high rate of success. Clinical features and radiographs are sufficient for the diagnosis in this case. The third presentation is OM superimposed to Charcot's neuroarthropathy, which mainly comprises midfoot or hindfoot. It starts with a plantar ulcer in a foot that has developed a deformity. The treatment is based on an accurate diagnosis that often includes magnetic resonance, and requires a complex surgery to preserve the midfoot and to avoid recurrent ulcers or foot instability. The final presentation is that of an OM without large soft tissue compromise secondary to a chronic ulcer or a previous unsuccessful surgery secondary to minor amputation or debridement. There is often a small ulcer with a positive probe to bone test over a bony prominence. Diagnosis is made by clinical features, radiographs, and laboratory tests. Treatment includes antibiotic therapy guided by surgical or transcutaneous biopsy, but this presentation often requires surgery. Different presentations of OM mentioned above need to be recognized because the diagnosis, type of culture, antibiotic treatment, surgical treatment, and prognosis are different upon the presentation.

Role of bone biopsy and deep tissue culture for antibiotic stewardship in diabetic foot osteomyelitis

OBJECTIVES

To describe organisms most frequently identified on bone biopsy or deep tissue culture and determine how culture data impacted antibiotic management in patients with diabetic foot osteomyelitis (DFO).

METHODS

We retrospectively reviewed patients admitted with a diabetic foot ulcer (DFU) between 3 March 2018 and 31 December 2019 and selected for patients diagnosed with infectious osteomyelitis (OM) of the lower extremity. We stratified patients by whether a bone biopsy or deep tissue culture was obtained and compared rates of antibiotic utilization with chi-squared and Fisher's exact tests.

RESULTS

Of 305 patients with a DFU, 152 (50%) were clinically diagnosed with DFO. Forty-seven patients received 41 deep tissue cultures and 29 bone biopsy cultures for a total of 70 cultures. Of 45 (64%) positive cultures, 36 (80%) had Gram-positive organisms and 19 (42%) had Gram-negative organisms. MDR organisms were isolated in 7 (15%) patients. Culture data resulted in antibiotic changes in 41 (87%) patients. Therapy was narrowed in 29 (62%) patients and broadened due to inadequate empirical coverage in 4 (9%) patients. Culture data from 18 (40%) patients showed susceptibility to an oral treatment regimen with high bioavailability. There was no significant difference in rates of antibiotic utilization at discharge between patients who underwent bone biopsy or deep tissue culture relative to those who did not (77% versus 75%, P = 0.86), although less MRSA coverage was used (34% versus 50%, P = 0.047).

CONCLUSIONS

In patients with DFO, deep tissue and bone biopsy cultures were infrequently obtained but resulted in targeted therapy changes in most patients. Culture data usually allowed for narrowing of antibiotics but revealed inadequate empirical coverage in a subset of patients.

Ultrasonographic features of diabetic foot osteomyelitis: a case series

OBJECTIVE

Osteomyelitis is a limb-threatening complication of diabetic foot ulcers. Early identification of the disease is key to ensuring successful prognosis. In this study, we describe ultrasonographic features for the identification of osteomyelitis.

METHOD

Patients were screened through clinical, ultrasonographic and probe-to-bone tests.

RESULTS

Ultrasonographic features in three patients that could be used to identify diabetic foot osteomyelitis included periosteal reaction, periosteal elevation, cortical erosions and presence of sequestrum, all of which were confirmed by a plain X-ray.

CONCLUSION

An ultrasonographic examination could be used for the early detection of osteomyelitis, which could help clinicians devise prompt treatment strategies.

Evaluation of Adherence to the Oral Antibiotic Treatment in Patients With Diabetic Foot Infection

Introduction: The knowledge about level of adherence to oral antibiotic treatment in diabetic patients with ulcer infection could be essential as a method of evaluation/monitoring of conservative treatment. Aim: To assess the adherence to oral antibiotic treatment in outpatients with diabetic foot infection (soft tissue vs. osteomyelitis) by 8-item structured, self-reported medication adherence scale. Methods: cross-sectional study was carried out with 46 consecutive patients who had diabetic foot infection (soft tissue or bone infection) and required antibiotic oral treatment at outpatient clinical setting. Medication adherence was tested using the Spanish version of the validated eight-item self-report MMAS-8. Results: patients with diabetic ulcer infection, had well level of adherence to antibiotic medication (7   ±   1.2 vs. 7.4   ±   1.5). Patients with lower level of adherence had lower level of satisfaction with the antibiotic medication. The profile of the patients with lower level of adherence were patients with primary level of education and patient who required more help to take the medication. Conclusion: Patients with diabetic foot infection demonstrated well level of adherence to antibiotic medication, independently of type of infection (soft tissue vs. osteomyelitis) by 8-item structured, self-reported medication adherence scale.

Serum Calcium Level Combined with Platelet Count May Be Useful Indicators for Assisted Diagnosis of Extremity Posttraumatic Osteomyelitis: A Comparative Analysis

Background

A previous study had reported that patients with osteomyelitis (OM) appeared to be more likely to develop hypocalcemia before and after surgery. Calcium sulfate (CS) is frequently used as a local antibiotic vehicle in the treatment of OM, which may also affect serum calcium level. However, whether changes of serum calcium level are caused by OM and/or local use of calcium sulfate remains unclear. Also, platelet (PLT) count plays a crucial predictive role in periprosthetic joint infections (PJIs), but its role in assisted diagnosis of OM is largely unknown. The purpose of this study was to determine whether serum calcium level and PLT count may be helpful in assisted diagnosis of PTOM.

Methods

Between January 2013 and December 2018, we analyzed 468 consecutive patients (392 males and 76 females), including 170 patients with posttraumatic OM (PTOM), 130 patients with aseptic bone nonunion (ABN), and 168 patients recovered from fractures with requirement of implant removal set as controls. Preoperative serological levels of calcium, phosphorus, and PLT were detected, and comparisons were conducted among the above three groups. Additionally, correlations and receiver operating characteristic (ROC) curves were displayed to test whether calcium level and PLT can differentiate patients with ABN and PTOM.

Results

Outcomes showed that the incidences of asymptomatic hypocalcemia (PTOM vs. ABN vs. controls = 22.94% vs. 6.92% vs. 8.82%, χ² = 21.098, P < 0.001) and thrombocytosis (PTOM vs. ABN vs. controls = 35.3% vs. 13.84% vs. 12.35%, χ² = 28.512, P < 0.001) were highest in PTOM patients. Besides, the mean serological levels of phosphorus in PTOM and ABN patients were significantly higher than those in the controls (P = 0.007). The Area Under the Curve (AUC) of the ROC curve outcomes revealed that, with the combination of serum calcium level with PLT count, the predictive role was acceptable (AUC 0.730, P < 0.001, 95% CI 0.681-0.780). Also, serological levels of calcium of 2.225 mmol/L and PLT count of 246.5 × 10⁹/L were identified as the optimal cut-off values to distinguish patients with and without PTOM. However, age- and gender-related differences in serum calcium levels (age, P = 0.056; gender, P = 0.978) and PLT count (age, P = 0.363; gender, P = 0.799) were not found to be statistically significant in any groups. In addition, no significant correlations were identified between serum calcium level and PLT count (R = 0.010, P = 0.839).

Conclusions

Asymptomatic hypocalcemia and thrombocytosis appeared to be more frequent in this cohort with PTOM. Serological levels of calcium and PLT count may be useful biomarkers in screening patients suspected of PTOM.

Pathophysiology and Molecular Imaging of Diabetic Foot Infections

Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host's immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.

Pathophysiology and Molecular Imaging of Diabetic Foot Infections

Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host's immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.

Factors affecting the outcome of lower extremity osteomyelitis treated with microvascular free flaps: an analysis of 65 patients

Background

Free flaps have been a useful modality in the management of lower extremity osteomyelitis particularly in limb salvage. This study aimed to determine the factors affecting the outcome of free flap reconstruction in the treatment of osteomyelitis.

Methods

This retrospective study assessed 65 osteomyelitis patients treated with free flap transfer from 2015 to 2020. The treatment outcomes were evaluated in terms of the flap survival rate, recurrence rate of osteomyelitis, and amputation rate. The correlation between outcomes and comorbidities, causes of osteomyelitis, and treatment modalities was analyzed. The following factors were considered: smoking, peripheral artery occlusive disease, renal disease, diabetic foot ulcer, flap types, using antibiotic beads, and negative pressure wound therapy.

Result

Among the 65 patients, 21 had a severe peripheral arterial occlusive disease. Osteomyelitis developed from diabetic foot ulcers in 28 patients. Total flap failure was noted in six patients, and osteomyelitis recurrence was noted in eight patients, for which two patients underwent amputation surgery during the follow-up period. Only end-stage renal disease had a significant correlation with the recurrence rate (odds ratio = 16.5, p = 0.011). There was no significant relationship between outcomes and the other factors.

Conclusion

This study showed that free flaps could be safely used for the treatment of osteomyelitis in patients with comorbidities and those who had osteomyelitis developing from diabetic foot ulcers. However, care should be taken in patients diagnosed with end-stage renal disease.

Long-Term Complications after Surgical or Medical Treatment of Predominantly Forefoot Diabetic Foot Osteomyelitis: 1 Year Follow Up

AIM

To compare long-term complications according to the treatment received for management of diabetic foot osteomyelitis (surgical or medical) at 1 year follow up.

DESIGN AND PARTICIPANTS

A prospective observational study was conducted involving 116 patients with diabetic foot osteomyelitis. The patients received surgical or medical treatment based on the principles described in the literature. To register the development of a complication, both groups of treatments were followed-up 1 year after the ulcer had healed.

RESULTS

Ninety-six (82.8%) patients received surgical treatment and 20 (17.2%) medical treatment. No differences were found in the time to healing between both groups of treatment, 15.7 ± 9.2 weeks in the surgical group versus 16.4 ± 12.1 weeks in the medical group; p = 0.103. During follow up, 85 (73.3%) patients developed complications without differences between both groups, 68 (70.8%) in the surgical group versus 17 (85%) in the medical group (p = 0.193). The most common complication in both groups was re-ulceration. We did not observe significant differences comparing complication-free time survival between both treatments (p = 0.665).

CONCLUSION

The onset of complications after healing in patients who suffered from diabetic foot osteomyelitis was not associated with the treatment received. Surgical and medical approaches to the management of diabetic foot osteomyelitis produced similar results in long-term follow up.

Treating Diabetic Foot Osteomyelitis: A Practical State-of-the-Art Update

Background and Objectives: Diabetic foot osteomyelitis (DFO) can be difficult to treat and securing optimal clinical outcomes requires a multidisciplinary approach involving a wide variety of medical, surgical and other health care professionals, as well as the patient. Results of studies conducted in the past few years have allowed experts to formulate guidelines that can improve clinical outcomes. Material and Methods: We conducted a narrative review of the literature on treat- ment of DFO, with an emphasis on studies published in the last two years, especially regarding antimicrobial therapies and surgical approached to treatment of DFO, supplemented by our own extensive clinical and research experience in this field. Results: Major amputations were once com- mon for DFO but, with improved diagnostic and surgical techniques, "conservative" surgery (foot- sparing, resecting only the infected and necrotic bone) is becoming commonplace, especially for forefoot infections. Traditional antibiotic therapy, which has been administered predominantly in- travenously and frequently for several months, can often be replaced by appropriately selected oral antibiotic regimens following only a brief (or even no) parenteral therapy, and given for no more than 6 weeks. Based on ongoing studies, the recommended duration of treatment may soon be even shorter, especially for cases in which a substantial portion of the infected bone has been resected. Using the results of cultures (preferably of bone specimens) and antimicrobial stewardship princi- ples allows clinicians to select evidence-based antibiotic regimens, often of a limited pathogen spec- trum. Intra-osseous antimicrobial and surgical approaches to treatment are also evolving in light of ongoing research. Conclusions: In this narrative, evidenced-based review, taking consideration of principles of antimicrobial stewardship and good surgical practice, we have highlighted the recent literature and offered practical, state-of-the-art advice on the antibiotic and surgical management of DFO.

Medical Versus Surgical Treatment for the Management of Diabetic Foot Osteomyelitis: A Systematic Review

A systematic review and quality assessment was performed to assess the management of diabetic foot osteomyelitis by medical or surgical treatment. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist was used. All selected studies were evaluated using the Cochrane Risk of Bias Tool to assess the risk of bias for randomized controlled trials. The literature was revised using PubMed (Medline) and Embase (Elsevier) up to September 2020 to identify clinical trials assessing medical or surgical treatment to manage diabetic foot osteomyelitis. A total of six clinical trials that met our inclusion criteria, with a total of 308 participants. Healing rate, complete closure of the wound, and type of complications were the outcomes evaluated. Risk of bias assessment showed that only two of the six clinical trials included in the systematic review had a low risk of bias. Based on our findings, we believe that the management of diabetic foot osteomyelitis remains challenging. There are few high-quality clinical trials that both stratify clinical presentations and compare these treatments. We conclude that the available evidence is insufficient to identify the best option to cure diabetic foot osteomyelitis.

Diabetic Foot Infections: Bacterial Isolates From the Centers and Hospitals of Latin American Countries

Diabetic foot infections (DFIs) are one of the most important reasons for lower limb amputations. An adequate approach to the management of DFI implies control of infection using strategies of tissue debridement and empirical antibiotic treatment based on local microbiology. The aim of this study was to determine the bacterial isolates profile and antibiotic susceptibility patterns in samples from DFI from Latin American centers, on the premise that microbiology of this region differs from that of other continents and influences antimicrobial election. Three hundred and eighty-two samples from soft tissue and bone were studied from 17 centers of 4 countries. Three hundred and seven (80.4%; 95% confidence interval = 75.9-84.2) were positive. Gram negatives (GN) were isolated in 43.8% of all samples, not only in severe but also in mild infections, 51% in bone samples, more frequently in presence of ischemia (47% vs 38%; P = .07) and in wounds with longer duration of the lesion (30-20 days; P < .01). Staphylococcus aureus was the most frequent single germ (19.9%). Gram positives were isolated more frequently in patients without ischemia (53% vs 40%; P = .01). Enterococcus faecalis was the most frequent germ in bone samples (16.8%). Ciprofloxacin and trimethoprim-sulfamethoxazole were the oral antimicrobials most effective against GN. Trimethoprim-sulfamethoxazole and rifampicin were the oral antimicrobials most effective against Staphylococcus. Because of GN high antibiotic resistance patterns, patients treated in an ambulatory setting have to be controlled early after starting empiric treatment to assess response to therapy and hospitalize for parenteral antibiotics if oral treatment fails.

Utility of Blood Parameters to Detect Complications during Long-Term Follow-Up in Patients with Diabetic Foot Osteomyelitis

The evidence is still unclear regarding the role of blood parameters in detecting complications in patients who suffer from diabetic foot osteomyelitis (DFO). In this study, the aim was to identify the capacity of different blood parameters in the diagnosis and prediction of the onset of complications. A cross-sectional prospective study was carried out with 116 DFO patients. The following blood parameters were evaluated during 1 year of follow-up: leukocytes, neutrophils, lymphocytes, monocytes, eosinophils, basophils, erythrocyte sedimentation rate (ESR), glycemia, glycosylated hemoglobin, C-reactive protein (CRP), alkaline phosphatase, albumin, and creatinine. Complication events were assessed for each participant during the study period. We investigated the association between blood parameter values and the onset of complication events by conducting a receiver operating characteristic curve analysis. Eighty-five (73.3%) patients developed complications. Regarding blood parameters, higher values of lymphocytes and albumin were predictive factors at the 12-month follow-up once the ulcer had healed. Higher values of ESR had predictive and diagnostic value for the onset of complication events, and higher values of CRP and hyperglycemia were diagnostic factors since they were elevated during the occurrence of an event. In conclusion, after suffering from DFO, the elevation of lymphocytes, ESR, CRP, albumin, and glycemia could be useful in detecting and diagnosing patients who are likely to develop a complication. Serial blood tests are a useful tool for early detection by healthcare professionals to prevent complications.

Metatarsal Head Resections in Diabetic Foot Patients: A Systematic Review

A systematic review and proportional meta-analysis were carried out to investigate the complications that occur after surgical metatarsal head resection in diabetic foot patients. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) checklist recommendations were applied, and the selected studies were evaluated using a Strengthening the Reporting of Observational studies in Epidemiology (STROBE) checklist. PubMed (Medline) and Embase (Elsevier) were searched in December 2019 to find clinical trials, cohort studies, or case series assessing the efficacy of the metatarsal head resection technique in diabetic foot patients. The systematic review covered 21 studies that satisfied the inclusion criteria and included 483 subjects. The outcomes evaluated were the time to heal, recurrence, reulceration, amputation, and other complications. The proportion of recurrence was 7.2% [confidence interval (CI) 4.0–10.4, p < 0.001], that of reulceration was 20.7% (CI 11.6–29.8, p < 0.001), and that of amputation was 7.6% (CI 3.4–11.8, p < 0.001). A heterogeneity test indicated I² = 72.6% (p < 0.001) for recurrences, I² = 94% (p < 0.001) for reulcerations, and I² = 79% (p < 0.001) for amputations. We conclude that metatarsal head resections in diabetic foot patients are correlated with significant complications, especially reulceration.

Guidelines on the diagnosis and treatment of foot infection in persons with diabetes (IWGDF 2019 update)

The International Working Group on the Diabetic Foot (IWGDF) has published evidence-based guidelines on the prevention and management of diabetic foot disease since 1999. This guideline is on the diagnosis and treatment of foot infection in persons with diabetes and updates the 2015 IWGDF infection guideline. On the basis of patient, intervention, comparison, outcomes (PICOs) developed by the infection committee, in conjunction with internal and external reviewers and consultants, and on systematic reviews the committee conducted on the diagnosis of infection (new) and treatment of infection (updated from 2015), we offer 27 recommendations. These cover various aspects of diagnosing soft tissue and bone infection, including the classification scheme for diagnosing infection and its severity. Of note, we have updated this scheme for the first time since we developed it 15 years ago. We also review the microbiology of diabetic foot infections, including how to collect samples and to process them to identify causative pathogens. Finally, we discuss the approach to treating diabetic foot infections, including selecting appropriate empiric and definitive antimicrobial therapy for soft tissue and for bone infections, when and how to approach surgical treatment, and which adjunctive treatments we think are or are not useful for the infectious aspects of diabetic foot problems. For this version of the guideline, we also updated four tables and one figure from the 2016 guideline. We think that following the principles of diagnosing and treating diabetic foot infections outlined in this guideline can help clinicians to provide better care for these patients.

Bone Regeneration in the Application of a New Device for Osteosynthesis in the Experiment

Background. Treatment of residual cavities after radical surgery for bone diseases is a vital problem of modern traumatology. Currently, there is an active search for devices both for osteosynthesis and bone-substituting masses. Aims. The purpose of this work was to test a new device for osteosynthesis. It can be used both for fixing bone fragments, and for studying the morphological features of bone regenerate in experiment.

Materials and methods. A device for bone osteosynthesis of tubular bones in an experiment (Patent of the Russian Federation N 20116121487) was applied. The device consisted of two half-bushings, fastened to each other by a fierce clamp. Polypropylene was used as the material for the half-bushings, therefore no immunological reactions were observed. On the inner surface there were silicone cylinders, which directed pressure on the fragments and did not disturb the nutrition of the periosteum. The experiment was performed on Wistar rats. The surgical defect of the femur was filled with hydroxyapatite. Two groups of animals were identified. The bone in the first group was fixed by the device. The wire cerclage was used in the second group.

Results. The study showed that the developed device does not disturb the nutrition of the periosteum, and also tightly fixes the osteoplastic material in the bone defect. Histological examination showed that bone regeneration was faster when the device was used. On the 21st day of the experiment, the regenerate filled the defect in the control group by 62 %, and in the experimental group by 73 %. The regenerate was represented by a woven bone. In all animals, bone regenerate formed a strong osteo-integrative connection with the maternal bone. In both groups, it looked like a mature bone tissue at the end of the experiment (28 days).

Conclusion. The data indicate that the device does not disturb the processes of bone formation and allows for more efficient use osteoplastic material.

Complications associated with the approach to metatarsal head resection in diabetic foot osteomyelitis

The aim of this study was to evaluate the recovery time and the development of complications in the dorsal and plantar approach to metatarsal head resections (MHR) in patients with diabetic foot ulcers complicated by osteomyelitis. A retrospective study was carried out involving 108 patients who underwent MHRs for the treatment of diabetic foot osteomyelitis. Two cohorts were defined: dorsal approach with incision closed with sutures and plantar approach with ulcer healed using conservative treatment. The main outcomes were the weeks until healing and complications related to the approaches. Fifty-three patients (49.1%) underwent a plantar approach and 55 (50.9%) a dorsal approach. Both approaches rendered similar healing times. However, the patients undergoing a dorsal approach developed more post-surgical complications than patients treated through a plantar approach. The dorsal approach intervention was performed on smaller and shallower ulcers; however, more complications developed at follow up using this approach than through a plantar approach for MHR complicated with osteomyelitis.