Early Complications of a Novel Retrograde Intramedullary Femoral Nail in the Treatment of Femur Fractures.

OBJECTIVES: To determine the early implant failure rate of a novel retrograde intramedullary femoral nail. DESIGN: Retrospective cohort study. SETTING: Academic level 1 trauma center. PATIENTS SELECTION CRITERIA: Patients aged 18 years and older with an acute OTA/AO 32-A, 32-B, 32-C, and 33-A fractures or periprosthetic distal femur fracture from April 2018 to April 2022 were included in the study. The 2 interventions compared were the Synthes Expert retrograde/antegrade femoral nail (or control implant) versus the next-generation retrograde femoral nail (RFN)-advanced retrograde femoral nail (RFNA or experimental implant) (Synthes, West Chester, PA). OUTCOME MEASURES AND COMPARISONS: Early implant-related complications between the experimental and control implants were assessed including locking screw back out, screw breakage, intramedullary nail failure, need for secondary surgery, and loss of fracture reduction. RESULTS: Three hundred fourteen patients were identified with a mean age of 31.0 years, and 62.4% of the patients being male. Open fractures occurred in 32.5% of patients with 3.8% of injuries being distal femur periprosthetic fractures. Fifty-six patients were in the experimental group and 258 patients in the control group. Mean follow-up was 46.8 weeks for the control cohort and 21.0 weeks for the experimental cohort. Distal interlocking screw back out occurred in 23.2% (13 of 56) of the experimental group patients and 1.9% (5 of 258) of the control group patients ( P < 0.0001). Initial diagnosis of interlocking screw back out occurred at an average of 3.2 weeks postoperatively (range, 2-12 weeks). Fifty-four percent of patients who sustained screw back out underwent a secondary operation to remove the symptomatic screws (12.5% of all patients treated with the experimental implant required an unplanned secondary operation due to screw back out). A logistic regression model was used to predict screw back out and found the experimental implant group was 4.3 times as likely to experience distal locking screw back out compared with the control group ( P = 0.01). CONCLUSIONS: The retrograde femoral nail-advanced implant was associated with a significantly higher rate of screw back out with a substantial number of unplanned secondary surgeries compared with the previous generation of this implant. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Safety of Prepping the External Fixator In Situ During Staged Internal Fixation of Pilon Fractures: A Retrospective Comparative Cohort Study.

OBJECTIVE: (1) To assess the rate of fracture-related infection (FRI) and unplanned reoperation of disinfecting and prepping in the external fixator (Ex-Fix) instrument during definitive open reduction and internal fixation (ORIF) of pilon fractures treated by a staged protocol and (2) to determine whether the amount of time from external fixation to ORIF influences the risk of FRI. DESIGN: Retrospective cohort study. SETTING: Level 1 academic trauma center. PATIENTS: One hundred thirty-three patients who underwent operative treatment for pilon fracture between 2010 and 2020. INTERVENTION: External fixation and ORIF with or without the Ex-Fix prepped in situ during definitive fixation. MAIN OUTCOME MEASUREMENTS: FRI and unplanned reoperation rates. RESULTS: 133 patients were enrolled, of which 47 (35.3%) had Ex-Fix elements prepped in situ. There was an overall infection rate of 23.3% and unplanned reoperation rate of 11.3%, and there was no significant difference in rates between the 2 cohorts. Patients with Ex-Fix elements prepped in situ who developed an FRI had a higher rate of MRSA and MSSA . Diabetes ( P = 0.0019), open fracture ( P = 0.0014), and longer (≥30 days) interval to ORIF ( P = 0.0001) were associated with postoperative FRI. CONCLUSIONS: Prepping elements of the Ex-Fix in situ did not lead to an increase in rates of FRI or unplanned reoperation. Although diabetes and open fracture were associated with FRI risk, a stronger association was a longer interval of Ex-Fix utilization before definitive internal fixation, specifically 30 days or greater. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Risk Factors for Infection and Subsequent Adverse Clinical Results in the Setting of Operatively Treated Pilon Fractures.

OBJECTIVE: To determine patient-specific and injury-specific factors that may predict infection and other adverse clinical results in the setting of tibial pilon fractures. DESIGN: Retrospective chart review. SETTING: Level 1 academic trauma center. PATIENTS: Two hundred forty-eight patients who underwent operative treatment for tibial pilon fractures between 2010 and 2020. INTERVENTION: External fixation and/or open reduction and internal fixation. MAIN OUTCOME MEASUREMENTS: Fracture-related infection rates and specific bacteriology, risk factors associated with development of a fracture-related infection, and predictors of adverse clinical results. RESULTS: Two hundred forty-eight patients were enrolled. There was an infection rate of 21%. The 3 most common pathogens cultured were methicillin-resistant Staphylococcus aureus (20.3%), Enterobacter cloacae (16.7%), and methicillin-resistant Staphylococcus aureus (15.5%). There was no significant difference in age, sex, race, body mass index, or smoking status between those who developed an infection and those who did not. Patients with diabetes mellitus ( P = 0.0001), open fractures ( P = 0.0043), and comminuted fractures (OTA/AO 43C2 and 43C3) ( P = 0.0065) were more likely to develop a fracture-related infection. The presence of a polymicrobial infection was positively associated with adverse clinical results ( P = 0.006). History of diabetes was also positively associated with adverse results ( P = 0.019). CONCLUSIONS: History of diabetes and severe fractures, such as those that were open or comminuted fractures, were positively associated with developing a fracture-related infection after the operative fixation of tibial pilon fractures. History of diabetes and presence of a polymicrobial infection were independently associated with adverse clinical results. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Bone-Prosthesis Junction for Active Tendon Implants: A Biomechanical Comparison of 2 Fixation Techniques.

PURPOSE: To study the biomechanical characteristics (percent stretch, stiffness, and ultimate load) of 2 distal fixation techniques for an active tendon implant used in the reconstruction of flexor tendons. METHODS: We evaluated percent stretch after cyclical loading and at failure, stiffness during load-to-failure, and peak load of 28 bone-prosthesis junctions using cadaveric canine middle phalanges to study 2 fixation techniques: metal cleat and screw versus polyester cords secured with a knot. RESULTS: The knot constructs displayed greater percent stretch during and following cyclical loading between 2 N and 50 N and at peak load. The screw construct showed greater stiffness from 50 N to 150 N during load-to-failure. Both fixation techniques failed at a mean peak load greater than 340 N. CONCLUSIONS: Both fixation techniques for active tendon implants withstood loads seen with passive and active motion in the immediate postoperative period. Knot constructs displayed significant stretch during cyclical and load-to-failure testing, which would need to be compensated for during surgery. The screw constructs showed greater stiffness than the constructs secured with the surgeon's knot, but failure created an intra-articular fracture. CLINICAL RELEVANCE: The results may aid the surgeon in choosing which fixation technique to use, during tensioning of cords, and in permitting active motion following surgery.