Background: Accurate identification of primary pathogens in foot infections remains challenging due to the diverse microbiome. Conventional culture may show false-positive or false-negative growth, leading to ineffective postoperative antibiotic treatment. Next-generation sequencing (NGS) has been explored as an alternative to standard culture in orthopedic infections. NGS is highly sensitive and can detect an entire bacterial genome along with genes conferring antibiotic resistance in a given sample. We investigated the potential use of NGS for accurate identification and quantification of microbes in infected diabetic foot ulcer (DFU). We hypothesize that NGS will aid identification of dominant pathogen and provide a more complete profile of microorganisms in infected DFUs compared to the standard culture method. Methods: Data were prospectively collected from 30 infected DFU patients who underwent operative treatment by a fellowship-trained orthopedic foot and ankle surgeon from October 2018 to September 2019. The average age of the patient was 60.4 years. Operative procedures performed were irrigation and debridement (12), toe or ray amputation (13), calcanectomies (4), and below-the-knee amputation (1). Infected bone specimens were obtained intraoperatively and processed for standard culture and NGS. Concordance between the standard culture and NGS was assessed. Results: In 29 of 30 patients, pathogens were identified by both NGS and culture, with a concordance rate of 70%. In standard culture, Staphylococcus aureus (58.6%) was the most common pathogen, followed by coagulase-negative Staphylococcus (24.1%), Corynebacterium striatum (17.2%), and Enterococcus faecalis (17.2%). In NGS, Finegoldia magna (44.8%) was the most common microorganism followed by S. aureus (41.4%), and Anaerococcus vaginalis (24.1%). On average, NGS revealed 5.1 (range, 1-11) pathogens in a given sample, whereas culture revealed 2.6 (range, 1-6) pathogens. Conclusion: NGS is an emerging molecular diagnostic method of microbial identification in orthopedic infection. It frequently provides different profiles of microorganisms along with antibiotic-resistant gene information compared to conventional culture in polymicrobial foot infection. Clinical use of NGS for management of foot and ankle infections warrants further investigation. Level of Evidence: Level II, diagnostic study.

Category: Diabetes; Other Introduction/Purpose: The incidence of Streptococcus agalactiae (Group B Streptococcus, GBS) infection in diabetic foot ulcers (DFU) has been on the rise. Severe soft tissue damage, which often leads to septicemia and amputation, has been reported in many cases. With the paucity of literature, we aimed to investigate the clinical outcome of GBS infected DFU patients. We hypothesize that GBS patients have a greater severity of infection as indicated by elevated inflammatory markers, more frequent wound complication, and a higher rate of unplanned readmission and reoperation. Methods: Data was retrospectively collected in a single academic orthopedic surgeon’s practice from February 2015 to October 2019. Seventy-eight patients with infected DFUs who underwent surgical treatment formed the basis of this study. Infected bone samples were obtained intraoperatively and sent for standard culture. The microbe data, demographic data (age, gender, race, ethnicity, and BMI), comorbidities, and initial lab values (HgA1C, CRP, ESR, WBC, and glucose) were recorded for all patients. Sixteen GBS infected DFU patients (20.5%) were identified. Among them, GBS infection occurred in 9 acute (<2 wks), 2 subacute (4-6 wks), and 5 chronic (>6 wks) DFUs. Clinical outcome was assessed by surgical outcome, wound healing status, post-operative complications, unplanned readmission, and unplanned reoperation within 3 months following initial surgery. Mean, standard deviation, percentage and range were calculated for patient demographics and inflammatory markers. Statistical significance of inflammatory markers between patients with and without GBS was also calculated. Results: The initial procedures were irrigation and debridement (n=11), toe amputation (n=1), ray amputation (n=2), transmetatarsal amputation (n=1), and a partial calcanectomy (n=1). Five GBS patients (31.3%), as compared to eighteen (29%) DFU patients without GBS, developed post-surgical complications (wound dehiscence, recurrent infection, septicemia) which required unplanned readmission and reoperation. Repeat operations were irrigation and debridement (n=1), metatarsal ray amputation (n=1), ray amputation (n=1), and below knee amputation (n=2) with average number of 2 repeat operations (range: 1 - 5). Hemoglobin A1C (p=.0067) was statistically higher in GBS patients. When comparing acute GBS ulcers (n=9) and acute ulcers without GBS (n=18), CRP (p=.037), HgA1C (p=.026), and blood glucose (p=.046) were all found to be significantly higher in patients with GBS DFUs. Conclusion: GBS infected DFU patients generally showed more extensive and severe soft tissue inflammation, as indicated by higher inflammatory markers at initial presentation. Compared to other patients with DFUs, GBS patients had significantly higher HgA1C values, and in those experiencing acute ulcers, had higher CRP, HgA1C, and blood glucose values. They have higher rates of post-operative complications that required unplanned readmission and reoperation at more proximal level. Surgeons should consider time sensitive and aggressive surgical treatment for GBS infected DFUs and counsel patients on the high risk of post- operative complications and repeat surgery. [Table: see text]

ImportanceLittle is known about the association of total knee replacement (TKR) removal from the Medicare inpatient-only (IPO) list in 2018 with outcomes in Medicare patients.ObjectiveTo evaluate (1) patient factors associated with outpatient TKR use and (2) whether the IPO policy was associated with changes in postoperative outcomes for patients undergoing TKR.Design, Setting, and ParticipantsThis cohort study included data from administrative claims from the New York Statewide Planning and Research Cooperative System. Included patients were Medicare fee-for-service beneficiaries undergoing TKRs or total hip replacements (THRs) in New York State from 2016 to 2019. Multivariable generalized linear mixed models were used to identify patient factors associated with outpatient TKR use, and with a difference-in-differences strategy to examine association of the IPO policy with post-TKR outcomes relative to post-THR outcomes in Medicare patients. Data analysis was performed from 2021 to 2022.ExposuresIPO policy implementation in 2018.Main Outcomes and MeasuresUse of outpatient or inpatient TKR; secondary outcomes included 30-day and 90-day readmissions, 30-day and 90-day postoperative emergency department visits, non–home discharge, and total cost of the surgical encounter.ResultsA total of 37 588 TKR procedures were performed on 18 819 patients from 2016 to 2019, with 1684 outpatient TKR procedures from 2018 to 2019 (mean [SD] age, 73.8 [5.9] years; 12 240 female [65.0%]; 823 Hispanic [4.4%], 982 non-Hispanic Black [5.2%], 15 714 non-Hispanic White [83.5%]). Older (eg, age 75 years vs 65 years: adjusted difference, −1.65%; 95% CI, −2.31% to −0.99%), Black (−1.44%; 95% CI, −2.81% to −0.07%), and female patients (−0.91%; 95% CI, −1.52% to −0.29%), as well as patients treated in safety-net hospitals (disproportionate share hospital payments quartile 4: −18.09%; 95% CI, −31.81% to −4.36%), were less likely to undergo outpatient TKR. After IPO policy implementation in the TKR cohort, there were lower adjusted 30-day readmissions (adjusted difference [AD], −2.11%; 95% CI, −2.73% to −1.48%; P &amp;lt; .001), 90-day readmissions ( −3.23%; 95% CI, −4.04% to −2.42%; P &amp;lt; .001), 30-day ED visits ( −2.45%; 95% CI, −3.17% to −1.72%; P &amp;lt; .001), 90-day ED visits (−4.01%; 95% CI, −4.91% to −3.11%; P &amp;lt; .001) and higher cost per encounter ($2988; 95% CI, $415 to $5561; P = .03). However, these changes did not differ from changes in the THR cohort except for increased TKR cost of $770 per encounter ($770; 95% CI, $83 to $1457; P = .03) relative to THR.Conclusions and RelevanceIn this cohort study of patients undergoing TKR and THR, we found that older, Black, and female patients and patients treated in safety-net hospitals may have had lesser access to outpatient TKRs highlighting concerns of disparities. IPO policy was not associated with changes in overall health care use or outcomes after TKR, except for an increase of $770 per TKR encounter.