The effect of external fixator on bone metabolism in patients with open fracture of extremities.

This experiment aimed to explore the influence mechanism of external fixator on open fracture. A total of 128 patients with open tibiofibular fractures were included in this study. The patients were randomly divided into external fixator group (n=64) and control group (n=64) according to the order of admission. Double-blind controlled observation was used. The levels of osteocalcin (BGP), ß-CTX, P1 NP, BALP, including haptoglobin (Hp), ceruloplasmin (CER), serum adrenocorticotropic hormone (ACTH), cortisol (COR), C-reactive protein (CRP), white blood cell (WBC) and interleukin-6 (IL-6) were recorded in different groups. The postoperative VAS score and quality of life were recorded. Log-rank was used to analyze the difference in postoperative adverse reaction rates among different groups. External fixation stent treatment increased BGP, PINP, and BALP expression and decreased ß-CTX, Hp, CER, ACTH, COR, CRP, WBC, and IL-6 levels. Patients in the external fixation stent group had significantly lower VAS score quality of life scores and incidence of adverse events than the control group. External fixation stents protect open fracture patients by promoting bone metabolism.

Iatrogenic open humeral shaft fractures following functional bracing.

INTRODUCTION: The treatment of closed humeral shaft fractures tends to be successful with functional bracing. Treatment failure due to iatrogenic conversion to an open fracture has not been described in the literature. We present a case series of patients that experienced open humeral shaft fractures after initially being treated with functional bracing for closed humeral shaft fractures and describe what factors are associated with this complication. MATERIALS AND METHODS: This was a retrospective case series performed at three level 1 trauma centers across North America. All nonoperatively treated humeral shaft fractures were reviewed from 2001 to 2023. Patients were included if they sustained a humeral shaft fracture, > 18 years old, were initially treated non-operatively with functional bracing which subsequently converted to an open fracture. Eight patients met inclusion criteria. All included patients were eventually treated with irrigation, debridement, and open reduction and internal fixation. Outcomes assessed included mortality rate, time until the fracture converted from closed to open, need for further surgery, and bony union. Descriptive statistics were used in analysis. RESULTS: The eight included patients on average were 65 ± 21.4 years old and had a body mass index (BMI) of 25.6 ± 5.2. Six patients were initially injured due to a fall. Time until the fractures became open on average was 5.2 ± 3.6 weeks. Three patients (37.5%) died within 1.8 ± 0.6 years after initial injury. The average Charlson Comorbidity Index (CCI) score was 4.5 ± 3.4. Three patients (37.5%) had dementia. Common characteristics among this cohort included a history of visual disturbances (50.0%), cerebrovascular accident (50.0%), smoking (50.0%), and alcohol abuse (50.0%). CONCLUSION: Conversion from a closed to open humeral shaft fracture after functional bracing is a potentially devastating complication. Physicians should be especially cognizant of patients with a low BMI, history of falling or visual disturbance, dementia, age ≥ 65, decreased sensorimotor protection, and significant smoking or alcohol history when choosing to use functional bracing as the final treatment modality. LEVEL OF EVIDENCE: IV.

[Modern concepts of interdisciplinary extremity reconstruction in open fractures]. / Moderne Konzepte der interdisziplinären Extremitätenrekonstruktion bei offenen Frakturen.

The orthoplastic approach involves the collaboration of orthopedic/trauma surgeons, vascular surgeons and reconstructive microsurgeons. In cases of complex limb fractures, the aims are to optimize blood flow, restore bone stability, reconstruct soft tissue defects, and enhance function and sensitivity. The early administration of antibiotics and a timely, high-quality debridement after initial interdisciplinary assessment are carried out. This is followed by fracture stabilization and temporary wound coverage in order to plan the definitive interdisciplinary procedure. This includes definitive osteosynthesis and soft tissue reconstruction, using local tissue transfer if feasible, or free tissue transfer in cases of extensive trauma zones. The orthoplastic approach allows for faster definitive stabilization, fewer operations, shorter hospital stays, lower complication and revision rates, higher cost-effectiveness and improved long-term function.

Microsurgical limb reconstruction in the non-concordant patient.

Substance misuse is common in patients undergoing limb reconstruction secondary to open fractures and fracture related infection. This group risk breaching the social contract with their treating team through reduced engagement with perioperative care. Potential problems include limited social support, intravenous access, analgesia and withdrawal. These factors may negatively influence the range of treatments offered to this group. We aimed to establish the prevalence and outcomes of the problematically non-concordant cohort in our limb reconstruction population, who we aim to treat equitably even where non-concordance is suspected pre-operatively. A retrospective study was performed using our prospectively collected free flap limb reconstruction database from December 2021-October 2023. Patient electronic health records were reviewed for demographics, perioperative details and outcomes. Eighty patients were identified, with 8 identified as problematically non-concordant (10%). All patients had a background of substance abuse; smoking (100%), alcohol (75%), IVDU (63%). Pre-operative non-concordance included absconding (43%), staff abuse (57%) and refusal of care (57%). Post-operative non-concordance included smoking (75%), mobilisation against instructions (75%), absconding (63%). No patients had free flap failure. Inpatient stay varied from 8-83 days, average 28.50% of patients did not attend follow-up. The expanding horizon of microsurgery means complex reconstruction is offered to a greater range of patients. Surgical teams should ensure that this service is offered equitably, individualising treatment plans to achieve the best outcomes. Risk of non-concordance is usually evident pre-operatively. We advise early involvement of substance misuse teams, discharge support and an understanding team to achieve good outcomes.

A review of 10 patients treated with the masquelet technique and microsurgical technique combined for Gustilo type III open tibial fractures.

BACKGROUND: Open tibial fractures often include severe bone loss and soft tissue defects and requires complex reconstructive operations. However, the optimal treatment is unclear. METHODS: This retrospective study enrolled patients with Gustilo type III open tibial fractures from January 2018 to January 2021 to assess the clinical utility of Masquelet technique together with microsurgical technique as a combined strategy for the treatment of open tibial fractures. The demographics and clinical outcomes including bone union time, infection, nonunion and other complications were recorded for analysis. The bone recovery quality was evaluated by the AOFAS Ankle-Hindfoot Scale score and the Paley criteria. RESULTS: We enrolled 10 patients, the mean age of the patients and length of bone defects were 31.7 years (range, 23-45 years) and 7.5 cm (range, 4.5-10 cm) respectively. Bone union was achieved for all patients, with an average healing time of 12.2 months (range, 11-16 months). Seven patients exhibited a bone healing time of less than 12 months, whereas 3 patients exhibited a bone healing time exceeding 12 months. No significant correlation was found between the length of bone loss and healing time. In addition, no deep infection or nonunion was observed, although 2 patients experienced wound fat liquefaction with exudates and 1 patient presented with a bloated skin flap. The average AOFAS Ankle-Hindfoot Scale score was 80.5 (range, 74-85), and all patients were evaluated as good or exellent based on the Paley criteria. CONCLUSIONS: Our study indicated that the use of the Masquelet technique and the microsurgical technique as a combined strategy is safe and effective for the treatment of Gustilo type III open tibial fractures.

Nurse-Initiated Protocol to Improve Timely Antibiotic Administration in Pediatric Open Fractures.

BACKGROUND: Early administration of antibiotics in the presence of open fractures is critical in reducing infections and later complications. Current guidelines recommend administering antibiotics within 60 min of patient arrival to the emergency department, yet trauma centers often struggle to meet this metric. OBJECTIVES: This study aims to evaluate the impact of a nurse-initiated evidence-based treatment protocol on the timeliness of antibiotic administration in pediatric patients with open fractures. METHODS: A retrospective pre-post study of patients who met the National Trauma Data Standard registry inclusion criteria for open fractures of long bones, amputations, or lawn mower injuries was performed at a Midwestern United States Level II pediatric trauma center. The time of patient arrival and time of antibiotic administration from preimplementation (2015-2020) to postimplementation (2021-2022) of the protocol were compared. Patients transferred in who received antibiotics at an outside facility were excluded. RESULTS: A total of N = 73 participants met the study inclusion criteria, of which n = 41 were in the preimplementation group and n = 32 were in the postimplementation group. Patients receiving antibiotics within 60 min of arrival increased from n = 24/41 (58.5%) preimplementation to n = 26/32 (84.4%) postimplementation (p< .05). CONCLUSIONS: Our study demonstrates that initiating evidence-based treatment orders from triage helped decrease the time from arrival to time of antibiotic administration in patients with open fractures. We sustained improvement for 24 months after the implementation of our intervention.

Quadruple Disruption of Superior Shoulder Suspensory Complex With Proximal Humerus Open Fracture-Dislocation: A Case Report.

CASE: A 34-year-old man was a restrained passenger involved in a high-speed rollover motor vehicle crash. The patient sustained a type 5 AC joint separation, severely comminuted intra-articular glenoid fracture with extension to the coracoid process base, displaced open scapular body fracture, a posterior shoulder dislocation of the glenohumeral joint, and a 2-part proximal humerus fracture. CONCLUSION: To our knowledge, this is the first report describing this injury pattern involving the superior shoulder suspensory complex with an associated open proximal humerus fracture-dislocation.

Reconstruction of the Medial Malleolus With Iliac Crest Autograft After Traumatic Loss: A Case Report.

CASE: A 19-year-old woman sustained an open ankle fracture with complete destruction of the left medial malleolus and significant soft-tissue loss. After temporizing external fixation and coverage with a rotational posterior tibial artery perforator flap, the medial malleolus was reconstructed with an autologous iliac crest bone graft and direct repair of the deltoid ligament. The patient achieved excellent improvement in functional outcomes at 21 months with adequate restoration of ankle motion. CONCLUSION: This case shows reconstruction of the medial malleolus with autologous iliac crest bone graft after traumatic loss can be a viable treatment option for young patients.

[Treatment of open fracture bone defect of distal femur with antibiotic cement column and bone graft].

OBJECTIVE: To investigate the efficacy of antibiotic cement column combined with iliac bone graft in the treatment of open fracture with bone defect of distal femur. METHODS: From October 2014 to March 2021, 16 patients of open fracture bone defect of distal femur were treated with antibiotic bone cement column and iliac bone graft, including 12 males and 4 females. The age ranged from 28 to 68 years old. There were 11 cases of traffic accident injury, 5 cases of falling injury, 3 cases as Gustilo type Ⅰ, 5 cases as type Ⅱ and 8 cases as type ⅢA. AO classification was used:9 cases of C2 type and 7 cases of C3 type. The time from injury to final bone grafting ranged from 4 to 119 days. The length of bone defect ranged from 2 to10 cm. Fractures healing time, complications and knee function Merchan score were recorded. RESULTS: All the 16 patients were followed up from 9 to 29 months. The incisions of 16 patients healed in one stage without postoperative infection, plate fracture, limb shortening and valgus and varus deformity. The healing time randed from 4 to 10 months . Knee joint function according to the Merchant scoring standard, showed that 8 cases were excellent, 4 cases were good, 3 cases were fair, and 1 case was poor. CONCLUSION: The use of antibiotic bone cement column combined with iliac bone graft in the treatment of open and complex bone defects of distal femur is an effective surgical method to prevent infection, assist fracture reduction, increase fixation strength and significantly reduce the amount of bone grafting.

Study on the risk factors of postoperative wound complications in patients with ankle fracture.

Wound complications after surgery for ankle fractures can lead to catastrophic consequences. The purpose of this study was to evaluate the risk factors of postoperative wound complications in patients with ankle fracture and to determine their effects on prognosis. 200 patients with ankle fracture treated in our hospital from October 2021 to December 2023 were analysed retrospectively. The total incidence of postoperative wound complications was 19% (38/200). Type of complications: wound edge necrosis 15 cases (39.47%), dehiscence (reopening of wound) 13 cases (34.21%), delayed healing (>30 days) 10 cases (26.32%); Univariate analysis showed that patients' age, body mass index (BMI), current smoking, alcoholism, diabetes mellitus, injury mechanism, open fracture, wound classification, higher American Society of Anesthesiologists (ASA) score and operation time were all associated with postoperative wound complications. Multivariate Logistic regression model shows: age ≥60 years old OR3.671 (1.875-5.937), BMI OR1.198 (1.143-1.324), current smoking OR2.727 (1.251-5.602), alcoholism OR1.143 (1.034-1.267), complicated with diabetes OR2.763 (1.236-4.852), injury mechanism (high vs. low and medium energy) OR2.437 (1.238-4.786), open fracture OR1.943 (1.8262.139), wound classification (II vs. I) OR4.423 (1.73511.674), ASA score (III-IV vs. I-II) OR1.307 (1.113-2.194) was an independent risk factor for postoperative wound complications in patients with ankle fracture. Further, ROC curves showed that these nine independent influences had high accuracy and validity in predicting postoperative wound complications in patients with ankle fractures. In conclusion, independent risk factors for postoperative complications of ankle fracture were age >60 years, BMI, injury mechanism, open fracture, wound classification (II vs. I), ASA score, current smoking, and alcoholism. The wound classification (II vs. I) has the highest diagnostic value.

[Application of antibiotic bone cement-coated plates internal fixation for primary treating Gustilo type â ¢B tibiofibular open fracture].

Objective: To explore the effectiveness of using antibiotic bone cement-coated plates internal fixation technology as a primary treatment for Gustilo type ⅢB tibiofibular open fractures. Methods: The clinical data of 24 patients with Gustilo type ⅢB tibiofibular open fractures who were admitted between January 2018 and December 2021 and met the selection criteria was retrospectively analyzed. Among them, there were 18 males and 6 females, aged from 25 to 65 years with an average age of 45.8 years. There were 3 cases of proximal tibial fracture, 6 cases of middle tibial fracture, 15 cases of distal tibial fracture, and 21 cases of fibular fracture. The time from injury to emergency surgery ranged from 3 to 12 hours, with an average of 5.3 hours. All patients had soft tissue defects ranging from 10 cm×5 cm to 32 cm×15 cm. The time from injury to skin flap transplantation for wound coverage ranged from 1 to 7 days, with an average of 4.1 days, and the size of skin flap ranged from 10 cm×5 cm to 33 cm×15 cm. Ten patients had bone defects with length of 2-12 cm (mean, 7.1 cm). After emergency debridement, the tibial fracture end was fixed with antibiotic bone cement-coated plates, and the bone defect area was filled with antibiotic bone cement. Within 7 days, the wound was covered with a free flap, and the bone cement was replaced while performing definitive internal fixation of the fracture. In 10 patients with bone defect, all the bone cement was removed and the bone defect area was grafted after 7-32 weeks (mean, 11.8 weeks). The flap survival, wound healing of the affected limb, complications, and bone healing were observed after operation, and the quality of life was evaluated according to the short-form 36 health survey scale (SF-36 scale) [including physical component summary (PCS) and mental component summary (MCS) scores] at 1 month, 6 months after operation, and at last follow-up. Results: All 24 patients were followed up 14-38 months (mean, 21.6 months). All the affected limbs were successfully salvaged and all the transplanted flaps survived. One case had scar hyperplasia in the flap donor site, and 1 case had hypoesthesia (grade S3) of the skin around the scar. There were 2 cases of infection in the recipient area of the leg, one of which was superficial infection after primary flap transplantation and healed after debridement, and the other was sinus formation after secondary bone grafting and was debrided again 3 months later and treated with Ilizarov osteotomy, and healed 8 months later. The bone healing time of the remaining 23 patients ranged from 4 to 9 months, with an average of 6.1 months. The scores of PCS were 44.4±6.5, 68.3±8.3, 80.4±6.9, and the scores of MCS were 59.2±8.2, 79.5±7.8, 90.0±6.6 at 1 month, 6 months after operation, and at last follow-up, respectively. The differences were significant between different time points ( P<0.05). Conclusion: Antibiotic bone cement-coated plates internal fixation can be used in the primary treatment of Gustilo type ⅢB tibiofibular open fractures, and has the advantages of reduce the risk of infection in fracture fixation, reducing complications, and accelerating the functional recovery of patients.

Analysis of the associated factors in postoperative wound infection following open reduction and internal fixation for elbow fracture.

Postoperative wound infections (PWIs) following open reduction and internal fixation (ORIF) for elbow fractures can significantly affect patient outcomes. Identifying associated risk factors is crucial for improving clinical practices and patient care. A retrospective analysis (June 2020-June 2023) at our institution involved 90 patients who underwent elbow ORIF. Thirty patients developed PWIs (case group), compared to 60 who did not (control group). Variables like anaemia, operation duration, hospital stay, blood loss, body mass index (BMI), age, hypoalbuminemia, smoking status, diabetes mellitus and open fractures were examined. Univariate and multivariate analyses determined the impact of these variables on PWI incidence, with statistical significance set at p < 0.05. The main pathogens identified were Escherichia coli among Gram-negative bacteria (59.46%) and Staphylococcus aureus among Gram-positive bacteria (40.54%). In the univariate analysis, hypoalbuminemia, anaemia, and lifestyle factors such as smoking showed higher prevalence in patients with PWIs. However, age and length of hospital stay did not significantly influence infection rates. The multivariate analysis further elucidated that anaemia, smoking, diabetes mellitus and open fractures were independent, significant predictors of PWIs. These findings highlight the complexity of factors influencing infection risk post-ORIF, underscoring the importance of both individual health conditions and surgical complications in patient outcomes. Anaemia, smoking, diabetes mellitus and open fractures significantly increase the risk of PWI after elbow ORIF. Early identification and management of these risk factors are imperative to reduce infection rates and improve postoperative recovery.

Masquelet combined with free-flap technique versus the Ilizarov bone transport technique for severe composite tibial and soft-tissue defects.

BACKGROUND: The treatment of bone and soft-tissue defects after open fractures remains challenging. This study aimed to evaluate the clinical efficacy of the Masquelet technique combined with the free-flap technique (MFFT) versus the Ilizarov bone transport technique (IBTT) for the treatment of severe composite tibial and soft-tissue defects. METHODS: We retrospectively analysed the data of 65 patients with tibial and soft-tissue defects and Gustilo type IIIB/C open fractures treated at our hospital between April 2015 and December 2021. The patients were divided into two groups based on the treatment method: group A (n = 35) was treated with the MFFT and internal fixation, and group B (n = 30) was treated with the IBTT. RESULTS: The mean follow-up period was 28 months (range 13-133 months). Complete union of both soft-tissue and bone defects was achieved in all cases. The mean bone-union times were 6 months (range 3-12 months) in group A and 11 months (range 6-23 month) in group B, with a significant difference between the two groups (Z = -4.11, P = 0.001). The mean hospital stay was 28 days (range 14-67 d) in group A which was significantly longer than the mean stay of 18 days (range 10-43 d) in group B (Z = -2.608, P = 0.009). There were no significant differences in the infection rate between group A (17.1 %) and group B (26.7%) (χ2 = 0.867, P = 0.352). The Total Physical Health Scores were 81.51 ± 6.86 (range 67-90) in group A and 75.83±16.14 (range 44-98) in group B, with no significant difference between the two groups (t = 1.894, P = 0.063). The Total Mental Health Scores were significantly higher in group A (90.49 ± 6.37; range 78-98) than in group B (84.70 ± 13.72; range 60-98) (t = 2.232, P = 0.029). CONCLUSION: Compared with IBTT, MFFT is a better choice of treatment for open tibial and soft-tissue defects with Gustilo IIIB/C fractures. IBTT is the preferred option when the tibial bone defect is large or if the surgeon's expertise in microsurgery is limited.

Outcomes following surgical fixation of Gustilo-Anderson IIIb open tibial fractures.

There is no consensus as to the optimal skeletal fixation method for Gustilo-Anderson IIIb fractures. External fixation methods have previously shown higher rates of superficial infection, whilst internal fixation has shown higher risk of deep infection, but lower risk of other complications. This paper investigates outcomes in open tibial fractures based on fixation method. A retrospective review was performed for patients presenting to an ortho-plastic unit with GA IIIb tibial fractures between June 2013 and October 2021. 85 patients were identified. The most common implant was an intramedullary nail (IMN), used in 29 patients (34.1%); open reduction and internal fixation (ORIF) was performed in 16 patients (18.8%). 18 patients (21.2%) were definitively managed with a frame alone. Mean follow-up from was 18 months (2-77). Patients with ORIF needed a mean of 3.37 operations; it was 2.48 for IMN which was significantly different from frames at 5.00 (p=0.000). The mean time to bony union after definitive fixation was 11.4 months. This differed depending on the implant used for fixation, with ORIF at 7.1 months, 10.1 for IMN, and frames at 17.2 months; ORIF significantly differed from frames (p=0.009). Superficial infection was common, seen in 38.8% of patients, and only 3 patients (4%) developed deep infections involving metalwork, with no difference in rates of either based on fixation method This study supports that ORIF has faster healing times, with less time to union compared to frames. It also shows that no implant was superior to another in terms of outcomes.

CURRENT CONCEPTS IN THE MANAGEMENT OF BOXER'S FRACTURE.

Fractures of the metacarpal particularly the 5th metacarpal is quite common among all hand fractures and has a high incidence in male adult population. Proper management of these fractures plays a key role in rehabilitation and early return to work thus reducing the economic burden. Treatment of these injuries depends on the type of injury: whether it is a closed/open fracture, degree of angulation at the fracture site and also mal-rotation and shortening of the finger. Non-operative management is suitable for fractures which are closed, non-displaced and without angulation or rotation. Open fractures, fractures with angulation and/or mal-rotation and fractures with neuro-vascular injury are more suitable for operative management. The acceptable angulation for conservative management for most studies is 70 degrees. Buddy strapping with a Futura splint provides good functional results. In fractures requiring operative intervention, K-wire fixation is a minimally invasive method of fixation, which in most cases has good functional results. Plate and screw fixation, however, is preferred for cases with significant comminution or multiple metacarpal fractures.

Improving the management of open tibia fractures, Malawi.

Objective: To assess the impact of an open fracture intervention bundle on clinical management and patient outcomes of adults in Malawi with open tibia fractures. Methods: We conducted a before-and-after implementation study in Malawi in 2021 and 2022 to assess the impact of an open fracture intervention bundle, including a national education course for clinical officers and management guidelines for open fractures. We recruited 287 patients with open tibia fractures. The primary outcome was a before-and-after comparison of the self-reported short musculoskeletal function assessment score, a measure of patient function. Secondary outcomes included clinical management; and clinician knowledge and implementation evaluation outcomes of 57 health-care providers attending the course. We also constructed multilevel regression models to investigate associations between clinical knowledge, patient function, and implementation evaluation before and after the intervention. Findings: The median patient function score at 1 year was 6.8 (interquartile range, IQR: 1.5 to 14.5) before intervention and 8.4 (IQR: 3.8 to 23.2) after intervention. Compared with baseline scores, we found clinicians' open fracture knowledge scores improved 1 year after the intervention was implemented (mean posterior difference: 1.6, 95% highest density interval: 0.9 to 2.4). However, we found no difference in most aspects of clinicians' open fracture management practice. Conclusion: Despite possible improvement in clinician knowledge and positive evaluation of the intervention implementation, our study showed that there was no overall improvement in clinical management, and weak evidence of worsening patient function 1 year after injury, after implementation of the open fracture intervention bundle.

Early Return of Motion in Patients With Intramedullary Screw Placement for Metacarpal and Phalangeal Fracture Fixation.

INTRODUCTION: Hand fractures are associated with significant morbidity. Current management standards often result in prolonged immobilization, stiffness, and delayed return to functional use. Intramedullary (IM) compression screws offer minimal soft tissue disruption and early postoperative active motion. In this study, we describe our outcomes after intraosseous fracture fixation using IM cannulated headless screws for a multitude of fracture patterns. METHODS: This study is a retrospective review of patients who underwent IM screw placement for fixation of metacarpal and phalangeal fractures by a single surgeon from 2017 to 2022. Data were collected to include patient demographics, fracture details, postoperative complications, and follow-up. Time to range of motion and return to unrestricted motion was recorded. RESULTS: There were 69 patients with 92 fractures (n = 54 metacarpal, n = 38 phalanx). The median patient age was 45 years (range, 18-89 years) with 75.4% males. Majority presented with a single fracture (n = 50, 72.5%), and 38 patients (55.1%) had open fractures. Small finger was the most affected digit (n = 35, 37.6%). The median time to allow range of motion from surgery was 8.7 days (interquartile range, 0-32) with 32 days (interquartile range, 10-62) for unrestricted use of the hand. Thirty-five patients (50.7%) were allowed controlled motion from the first postoperative day. One patient had loss of reduction requiring reintervention for hardware removal, and 1 patient had superficial skin infection managed with oral antibiotics. CONCLUSIONS: Our findings indicate that the IM screw provides reliable fixation for a wide variety of fracture patterns with a low complication rate and offers early return to functional use.

The Bioburden Associated with Severe Open Tibial Fracture Wounds at the Time of Definitive Closure or Coverage: The BIOBURDEN Study.

BACKGROUND: Infection is common following high-energy open tibial fractures. Understanding the wound bioburden may be critical to infection risk reduction strategies. This study was designed to identify the bioburden profile of high-energy open tibial fractures at the time of definitive wound closure or coverage and determine the relationship to subsequent deep infection. METHODS: This multicenter prospective study enrolled 646 patients with high-energy open tibial fractures requiring a second debridement surgery and delayed wound closure or coverage. Wound samples were obtained at the time of definitive closure or coverage and were cultured in a central laboratory. Cultures were also subsequently obtained from patients who underwent a fracture-site reoperation. RESULTS: Two hundred and six (32%) of the wounds had a positive culture at the time of closure or coverage. A single genus was identified in 154 (75%) of these positive cultures and multiple genera, in 52 (25%). Gram-positive cocci (GPCs) were identified in 98 (47%) of the positive cultures. Staphylococci were identified in 64 (31%) of the cultures, and 53 (83%) of these were coagulase-negative (CONS). Enterococci were identified in 26 (13%) of the cultures. Gram-negative rods (GNRs) were identified in 100 (49%) of the cultures; the most frequent GNR genera identified were Enterobacter (39, 19%) and Pseudomonas (21, 10%). Positive cultures were subsequently obtained from 154 (50%) of 310 revision surgeries. A single genus was identified in 85 (55%) of the 154 and multiple genera, in 69. GPCs were identified in 134 (87%) of the 154 positive cultures, staphylococci were identified in 94 (61%), and GNRs were identified in 100 (65%). CONCLUSIONS: The bioburden in high-energy open tibial fractures at delayed closure or coverage was often characterized by pathogens of multiple genera and of genera that are nonresponsive to typically employed antibiotic prophylaxis. Awareness of the final wound bioburden might inform strategies to lower the infection rate. LEVEL OF EVIDENCE: Prognostic Level II . See Instructions for Authors for a complete description of levels of evidence.