Intra-surgical Site Vancomycin Powder Application in Infected Diabetic Heel Ulcers with Calcaneal Osteomyelitis
Authors: Brodell James D. , Oh Irvin 
Published: November 2020

Category: Diabetes; Hindfoot Introduction/Purpose: The treatment of diabetic heel ulcers (DHU) with osteomyelitis is challenging, and dismal clinical results have been reported after calcanectomy, with reported revision rates of 0-63.5%. The topical application of vancomycin powder has reported to be beneficial in foot and ankle surgery amongst diabetic patients. However, no studies have examined the efficacy of intra-surgical site vancomycin powder application in DHU surgery. There are potential risks of intra-surgical site vancomycin powder application, such as the selection of gram-negative and multi-drug resistant bacteria, and increased wound complications. Thus, we aimed to 1) assess the clinical outcomes of calcanectomy for DHU and 2) investigate the clinical efficacy of intra-surgical site vancomycin powder application in patients who underwent partial- or total calcanectomies performed to treat infected DHU with osteomyelitis. Methods: This study was approved by our institution’s Research Subjects Review Board. Subjects were identified utilizing current procedural terminology code 28120 (Partial excision bone; talus or calcaneus) for partial or total calcanectomies performed at our academic institution. Thirty-eight calcanectomies performed secondary to DHU with osteomyelitis were identified. Patient demographics (age, sex, gender, body mass index), preoperative labs (hemoglobin A1c, blood glucose, white blood cell, erythrocyte sedimentation rate, C-reactive protein, serum creatinine, hemoglobin), ASA Class, peripheral arterial disease assessed by ankle-brachial index, Charleston Comorbidity Index, and intra-surgical site application of vancomycin powder were recorded. Duration of follow-up, type and quantity of systemic antibiotics administered during surgery, surgical complications, and return to the operating room (RTOR) were also recorded. There were two cohorts: those whose surgical wound was closed without vancomycin powder (initial 25 patients; ‘novancomycin’ group) versus those whose surgical site was closed with vancomycin powder (later 13 patients; ‘vancomycin’ group). Results: The average follow-up was 26.1 +- 15.0 months. Surgical pathology confirmed negative bone resection margins for all patients. Nineteen patients required an unplanned RTOR (50.0%). A revision amputation was performed in fifteen extremities (39.5%). Thirteen patients received intrawound vancomycin at closure, and 25 did not. Nine of thirteen (69.2%) patients who received vancomycin powder required RTOR. This includedTwo below-knee amputations (BKA), two irrigation and debridements (I&D), and six revision or total calcanectomies. There was a significantly higher rate of RTOR in the vancomycin cohort relative to the no-vancomycin cohort (76.9% vs 36.0%, p=0.038). Of the 25 no-vancomycin group, 17 did not return to the OR, 4 underwent BKA, 1 had I&D, and 2 required revision or total calcanectomy. Conclusion: In our cohort, calcanectomy performed for the surgical management of DHU with osteomyelitis yielded a high rate (50%) of unplanned follow-up procedures. Intra-surgical site vancomycin powder application during wound closure after calcanectomy did not result in clinical benefit and is likely unnecessary. The risk and benefit profile of intra-surgical site vancomycin powder application for diabetic foot infection surgery needs to be further investigated.