A New Source of Mutilating Hand Injuries: The Side-by-Side Utility Terrain Vehicle.

BACKGROUND: Rates of mutilating hand injuries are increasing from accidents caused by all-terrain vehicles (ATVs) and the recently popularized side-by-side utility terrain vehicles (UTVs). Increasing surgeon familiarity with upper extremity (UE) injury patterns, severity, and outcomes following ATV and UTV accidents may improve patient care and advocacy. METHODS: Retrospective comparisons of UE injury patterns, severity, hospital and intensive care unit (ICU) admission lengths, and number of operations were made between ATVs and UTVs. Findings were analyzed with Fisher exact tests, multivariate analysis of variance, analyses of variance with post hoc analyses, and multiple linear regressions. RESULTS: A total of 154 cases were identified for inclusion (ATV, n = 87; UTV, n = 67). Patient ages ranged from 4 to 89 years. The UTV group contained significantly more hand and finger injuries, and more of the fractures were open ( P = 0.005, P < 0.001, and P < 0.001, respectively). Riders of UTVs had nearly three times as many mutilating hand injuries and a nearly ninefold increase in amputations compared with ATV riders ( P < 0.001 and P < 0.001, respectively). On average, the UTV group spent 2.5 additional days in the hospital, 0.91 additional days in an ICU, and had 1.3 additional operations ( P = 0.001, P = 0.007, and P < 0.001, respectively). Vehicle type was the only variable significantly correlated with days in the hospital, ICU, and number of UE operations ( P = 0.002, P = 0.008, and P < 0.001, respectively). CONCLUSIONS: Hand surgeons are in a unique position to serve as forerunners for increasing public awareness of off-road vehicle risks and promoting rider safety. Collaborating with manufacturers and emergency care providers and directing teaching initiatives may improve patient outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

Postless Hip Distraction Systems Decrease the Amount of Traction Force Needed to Obtain Adequate Hip Distraction Versus a Conventional Post Hip Distractor.

PURPOSE: To directly compare hip distraction distance and traction force data for hip arthroscopy performed using a post-basedsystem versus a postless system. METHODS: Adult patients undergoing primary hip arthroscopy for femoroacetabular impingement were prospectively enrolled. Before March 26, 2019, arthroscopy was performed using a post-based system. After this date, the senior author converted to using a postless system. Intraoperative traction force and fluoroscopic distraction distance were measured to calculate hip stiffness coefficients at holding traction (k-hold) and maximal traction (k-max). We used multivariable regression analysis to determine whether postless arthroscopy was predictive of lower stiffness coefficients when controlling for other relevant patient-specific factors. RESULTS: Hip arthroscopy was performed with a post-based system in 105 patients and with a postless system in 51. Mean holding traction force (67.5 ± 14.0 kilograms-force [kgf] vs 55.8 ± 15.3 kgf) and mean maximum traction force (96.0 ± 16.6 kgf vs 69.9 ± 14.1 kgf) were significantly lower in the postless group. On multivariable analysis, postless traction was an independent predictor of decreased k-hold (ß = -31.4; 95% confidence interval, -61.2 to -1.6) and decreased k-max (ß = -90.4; 95% confidence interval, -127.8 to -53.1). Male sex, Beighton score of 0, and poor hamstring flexibility were also predictors of increased k-hold and k-max in the multivariable model. CONCLUSIONS: Postless traction systems decrease the amount of traction force required for adequate hip distraction for both maximal and holding traction forces when compared with post-based systems. Postless traction systems may help further reduce distraction-type neurologic injuries and pain after hip arthroscopy by lowering the traction force required to safely distract the hip. LEVEL OF EVIDENCE: Level III, prospective cohort-historical control comparative study.

The Prevalence of Metabolic and Endocrine Disturbances on Fracture Nonunion.

OBJECTIVE: This study aims to determine the prevalence of metabolic disturbance in all fracture nonunion cases and identify the most common endocrine abnormalities seen using a simple screening algorithm. METHODS: A retrospective review study was performed evaluating patients who underwent operative intervention for nonunion from January 2010 to December 2018 at 2 level-1 trauma centers. Preoperative laboratory values were recorded for a 9-test "nonunion panel." A metabolic or endocrine abnormality, specifically an abnormality in the thyroid or parathyroid axis, was evaluated. RESULTS: 42% of patients had an undiagnosed metabolic laboratory abnormality. When multiple tests were used, the rate of metabolic dysfunction was between 60% and 75%, depending on the definition of vitamin D insufficiency vs deficiency used. CONCLUSION: Results indicate a relatively high prevalence of metabolic disturbance in patients with nonunion and suggest metabolic screening for all nonunion patients not only those without a mechanical or infectious cause. LEVEL OF EVIDENCE: IV, retrospective case series.

Bone penetrance of locally administered vancomycin powder in a rat femur fracture model.

INTRODUCTION: Locally delivered, crystalline vancomycin has been suggested as a potential prophylactic measure against the development of deep and superficial surgical site infection. Clinical expectations regarding the duration and peak of drug concentration in local tissues following administration are unknown. Our goal was to develop concentration vs time curves for locally administered vancomycin powder in a high-energy, open femur fracture rat model in local tissues and to compare that data to two well performed similar, systemic administration studies. METHODS: After approval for animal research, 24 adult Sprague-Dawley rats sustained closed, midshaft femoral fracture under anesthesia. Fractures were caused via blunt guillotine with 750g metal rod dropped 50cm. Injured hindlimbs were surgically opened at fracture to simulate open injury and stabilized using 0.054 Kirschner wires. Vancomycin powder was administered using weight-based protocol (goal: 25mg/kg). Rats were sacrificed in groups of 4 at 4, 8, 24, 48, 72, 96h. Samples harvested included rat-tail venous blood prior to sacrifice, and femoral bone and anterior thigh soft-tissue were harvested post-mortem. High Performance Liquid Chromatography (HPLC) was performed on all samples. RESULTS: Concentration vs. time curves demonstrated that the surrounding soft-tissues demonstrated highest maximum concentration (1.5mg vancomycin/g muscle). Bone reached maximum average of 199µg vancomycin/g femur: approximately 13% of maximal soft-tissue absorption. Plasma reached maximum concentration of 1.8µg/mL plasma. All peaks at t=4h. Within 48h, average muscle vancomycin concentration dropped to 3µg/g muscle (0.2% maximum muscle concentration) and the average bone concentration dropped to 1.9µg/g femur (0.9% maximum bone concentration). Vancomycin was undetectable on all samples at 96h. Comparison to classical animal studies suggest local delivery to bone exceeds that of IV dosing for approximately 48h and may peak near concentrations of 102 multiples. CONCLUSIONS: Locally administered vancomycin provides drug delivery in excess of IV dosing for approximately 48h after intervention. Exponential decay demonstrates rapid removal of drug to near undetectable levels in bone, plasma, and local soft tissue thereafter in a rat model. Local delivery may generate concentrations exceeding that achievable by steady state systemic dosing for 48h.