41 results on '"Halvorson JJ"'
Search Results
2. The efficacy and duration of intra-articular corticosteroid injection for knee osteoarthritis: a systematic review of level I studies.
- Author
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Hepper CT, Halvorson JJ, Duncan ST, Gregory AJ, Dunn WR, Spindler KP, Hepper, C Tate, Halvorson, Jason J, Duncan, Stephen T, Gregory, Andrew J M, Dunn, Warren R, and Spindler, Kurt P
- Published
- 2009
3. The Long-Term Agroecosystem Research Cropland Common Experiment at Northern Plains.
- Author
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Liebig MA, Whippo CW, Saliendra NZ, Scott DA, Archer DW, Clemensen AK, Halvorson JJ, Friedrichsen CN, Christensen RG, and Igathinathane C
- Subjects
- Glycine max, Crop Production methods, Zea mays, Triticum, Soil, Conservation of Natural Resources methods, Crops, Agricultural, Agriculture methods
- Abstract
Cropland agriculture in the northern Great Plains is challenged by variable weather, agricultural intensification, and competing use for energy development. Innovative cropland practices that address these challenges are needed to ensure regional agriculture can sustainably meet future food, fuel, and fiber demand. In response to this need, the Northern Plains Long-Term Agroecosystem Research network site established a cropland experiment in 2019 that contrasts prevailing and alternative practices at plot and field scales over a proposed 30-year time frame. The experimental site is located on the Area IV Soil Conservation Districts Cooperative Research Farm near Mandan, ND. Cropping practices for the first 6 years of the experiment were developed with input from stakeholders and include a 3-year crop rotation of spring wheat (Triticum aestivum L.), corn (Zea mays L.), and soybean (Glycine max L.) with cover crops (alternative practice) and without (prevailing practice). The prevailing practice also involves the removal of crop residue, while a second alternative practice of perennial forages is included in the plot-scale experiment. Biophysical measurements are made at both spatial scales at frequencies aligned with approved methods for each agronomic and environmental metric. Findings from the first 6 years of the experiment will help identify tradeoffs associated with cover crop use and residue removal in dryland cropping systems. In the future, the experiment will adopt a knowledge co-production approach whereby researchers and stakeholders will work collaboratively to identify problems, implement research, and interpret results., (© 2024 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.)
- Published
- 2024
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4. Oxidation of Small Phenolic Compounds by Mn(IV).
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Gruenberg MG, Halvorson JJ, Hagerman AE, Enoma IG, and Schmidt MA
- Abstract
Plant secondary metabolites, including phenolics, represent a large quantity of organic material that enters soil and contributes to the formation of soil organic matter (SOM). The process of phenolics forming SOM remains poorly understood. One possible mechanism is oxidation of the phenolic compound catalyzed by redox active metals such as manganese (Mn) and iron (Fe) in soils. In this work, we report how three phenolic compounds react with a redox active environmentally relevant metal, Mn(IV). The reactions were monitored via nuclear magnetic resonance (NMR), high-performance liquid chromatography (HPLC), and direct CO
2 measurements. Using these techniques, we demonstrate that gallic acid reacts with Mn(IV) less efficiently than pyrogallol. The products of the gallic acid:Mn(IV) reaction are more oxidized than the products of the pyrogallol reaction. Gallic acid produces small molecules and releases CO2 , while pyrogallol produces a less oxidized product, likely a quinone, and releases less CO2 . Benzoic acid did not react with Mn(IV). This work provides a framework for how different classes of plant secondary metabolites may be degraded abiotically by redox active metals in soil.- Published
- 2024
- Full Text
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5. Skin Antisepsis before Surgical Fixation of Extremity Fractures.
- Author
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Sprague S, Slobogean G, Wells JL, O'Hara NN, Thabane L, Mullins CD, Harris AD, Wood A, Viskontas D, Apostle KL, O'Toole RV, Joshi M, Johal H, Al-Asiri J, Hymes RA, Gaski GE, Pilson HT, Carroll EA, Babcock S, Halvorson JJ, Romeo NM, Matson CA, Higgins TF, Marchand LS, Bergin PF, Morellato J, Van Demark RE 3rd, Potter GD, Gitajn IL, Chang G, Phelps KD, Kempton LB, Karunakar M, Jaeblon T, Demyanovich HK, Domes CM, Kuhn GR, Reilly RM, Gage MJ, Weaver MJ, von Keudell AG, Heng M, McTague MF, Alnasser A, Mehta S, Donegan DJ, Natoli RM, Szatkowski J, Scott AN, Shannon SF, Jeray KJ, Tanner SL, Marmor MT, Matityahu A, Fowler JT, Pierrie SN, Beltran MJ, Thomson CG, Lin CA, Moon CN, Scolaro JA, Amirhekmat A, Leonard J, Pogorzelski D, Bzovsky S, Heels-Ansdell D, Szasz OP, Gallant JL, Della Rocca GJ, Zura RD, Hebden JN, Patterson JT, Lee C, O'Hara LM, Marvel D, Palmer JE, Friedrich J, D'Alleyrand JG, Rivera JC, Mossuto F, Schrank GM, Guyatt G, Devereaux PJ, and Bhandari M
- Subjects
- Humans, 2-Propanol administration & dosage, 2-Propanol adverse effects, 2-Propanol therapeutic use, Antisepsis methods, Canada, Ethanol, Extremities injuries, Extremities microbiology, Extremities surgery, Preoperative Care adverse effects, Preoperative Care methods, Skin microbiology, Cross-Over Studies, United States, Anti-Infective Agents, Local administration & dosage, Anti-Infective Agents, Local adverse effects, Anti-Infective Agents, Local therapeutic use, Chlorhexidine administration & dosage, Chlorhexidine adverse effects, Chlorhexidine therapeutic use, Iodine administration & dosage, Iodine adverse effects, Iodine therapeutic use, Surgical Wound Infection etiology, Surgical Wound Infection prevention & control, Fractures, Bone surgery, Fracture Fixation
- Abstract
Background: Studies evaluating surgical-site infection have had conflicting results with respect to the use of alcohol solutions containing iodine povacrylex or chlorhexidine gluconate as skin antisepsis before surgery to repair a fractured limb (i.e., an extremity fracture)., Methods: In a cluster-randomized, crossover trial at 25 hospitals in the United States and Canada, we randomly assigned hospitals to use a solution of 0.7% iodine povacrylex in 74% isopropyl alcohol (iodine group) or 2% chlorhexidine gluconate in 70% isopropyl alcohol (chlorhexidine group) as preoperative antisepsis for surgical procedures to repair extremity fractures. Every 2 months, the hospitals alternated interventions. Separate populations of patients with either open or closed fractures were enrolled and included in the analysis. The primary outcome was surgical-site infection, which included superficial incisional infection within 30 days or deep incisional or organ-space infection within 90 days. The secondary outcome was unplanned reoperation for fracture-healing complications., Results: A total of 6785 patients with a closed fracture and 1700 patients with an open fracture were included in the trial. In the closed-fracture population, surgical-site infection occurred in 77 patients (2.4%) in the iodine group and in 108 patients (3.3%) in the chlorhexidine group (odds ratio, 0.74; 95% confidence interval [CI], 0.55 to 1.00; P = 0.049). In the open-fracture population, surgical-site infection occurred in 54 patients (6.5%) in the iodine group and in 60 patients (7.3%) in the chlorhexidine group (odd ratio, 0.86; 95% CI, 0.58 to 1.27; P = 0.45). The frequencies of unplanned reoperation, 1-year outcomes, and serious adverse events were similar in the two groups., Conclusions: Among patients with closed extremity fractures, skin antisepsis with iodine povacrylex in alcohol resulted in fewer surgical-site infections than antisepsis with chlorhexidine gluconate in alcohol. In patients with open fractures, the results were similar in the two groups. (Funded by the Patient-Centered Outcomes Research Institute and the Canadian Institutes of Health Research; PREPARE ClinicalTrials.gov number, NCT03523962.)., (Copyright © 2024 Massachusetts Medical Society.)
- Published
- 2024
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6. Dual Plate Fixation of Periprosthetic Distal Femur Fractures.
- Author
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Andring NA, Kaupp SM, Henry KA, Helmig KC, Babcock S, Halvorson JJ, Pilson HT, and Carroll EA
- Subjects
- Adult, Humans, Aged, Aged, 80 and over, Middle Aged, Retrospective Studies, Fracture Fixation, Internal adverse effects, Bone Plates, Femur, Treatment Outcome, Femoral Fractures, Distal, Periprosthetic Fractures surgery, Periprosthetic Fractures etiology, Femoral Fractures surgery, Femoral Fractures etiology
- Abstract
Objectives: Dual implants for distal femur periprosthetic fractures is a growing area of interest for these challenging fractures with dual plating (DP) emerging as a viable construct for these injuries. In the current study, an experience with DP constructs is described., Design: Retrospective case series with comparison group., Setting: Level 1 academic trauma center., Patient Selection Criteria: Adults >50 years old sustaining comminuted OTA/AO 33-A2 or 33-A3 DFPF treated with either DP or a single distal femur locking plating (DFLP). Patients with simple 33-A1 fractures were excluded. Prior to 2018, patients underwent DFLP after which the treatment of choice became DP., Outcome Measures and Comparisons: Reoperation rate, alignment, and complications., Results: 34 patients treated with DFLP and 38 with DP met inclusion and follow up criteria. Average follow up was 18.2 ± 13.8 months in the DFLP group and 19.8 ± 16.1 months in the DP group ( P = 0.339). The average patient age in the DFLP group was 74.8 ± 7.3 years compared to 75.9 ± 11.3 years in the DP group. There were no statistical differences in demographics, fracture morphology, loss of reduction, or reoperation for any cause ( P >.05). DP patients were more likely to be weight bearing in the twelve-week postoperative period ( P <0.001) and return to their baseline ambulatory status ( P = 0.004) compared to DFLP patients., Conclusions: Dual plating of distal femoral periprosthetic fractures maintained coronal alignment with a low reoperation rate even with immediate weight bearing and these patients regained baseline level of ambulation more reliably as compared to patients treated with a single distal femoral locking plate., Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: E. A. Carroll is a paid consultant for DePuy Synthes, recieves royalties from Globus, is a speaker for the AO Foundation, and recieves research support from both Depuy Synthes and the AO Foundation. The remaining authors report no conflict of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2024
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7. Comparison of Lateral versus Medial Entry Femoral Traction Pin Complication Rates.
- Author
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Luo TD, Hussaini SH, Andring NA, Kelly EA, Carroll EA, and Halvorson JJ
- Subjects
- Humans, Traction adverse effects, Traction methods, Cellulitis, Femur surgery, Bone Nails adverse effects, Lower Extremity, Femoral Fractures epidemiology, Femoral Fractures surgery, Fracture Fixation, Intramedullary adverse effects, Arthritis, Infectious, Osteomyelitis, Ossification, Heterotopic
- Abstract
Distal femoral skeletal traction is a common procedure for the stabilization of fractures of the pelvis, acetabulum, and femur following trauma. Femoral traction pins are traditionally inserted via medial-to-lateral (MTL) entry to accurately direct the pin away from the medial neurovascular bundle. Alternatively, cadaveric studies have demonstrated low risk to the neurovascular bundle using a lateral-to-medial (LTM) approach. The purpose of this study was to compare the incidence of complications of LTM and MTL femoral traction pin placement at a single institution. This was a retrospective review of patients from the orthopaedic consult registry at a academic Level I Trauma Center. We identified 233 LTM femoral traction pin procedures in 231 patients and 29 MTL pin procedures in 29 patients. The two pin placement techniques were compared with respect to complications, specifically the incidence of neurovascular injury, cellulitis, septic arthritis, osteomyelitis, and heterotopic ossification after femoral traction pin placement. Two complications were reported. One patient developed heterotopic ossification along the pin tract after LTM traction pin placement. Another patient developed septic arthritis after LTM pin placement, likely attributable to retrograde intramedullary nailing of his open femur fracture rather than his traction pin. There were no reports of neurovascular injury, cellulitis, or osteomyelitis associated with pin placement. The complication rate was 0.9% for LTM group and 0.0% for MTL group (p = 0.616). LTM femoral traction pin placement is a safe procedure with a similarly low complication rate compared with traditional MTL placement when the limb is positioned in neutral alignment. (Journal of Surgical Orthopaedic Advances 32(4):259-262, 2023).
- Published
- 2023
8. Thermal Output of Oscillation Versus Forward Drilling of Bone.
- Author
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Medda S, Duffin MJ, Rosas S, Kessler RB, Babcock S, Halvorson JJ, Carroll EA, and Pilson HT
- Subjects
- Humans, Temperature, Femur surgery, Bone and Bones surgery, Orthopedic Procedures
- Abstract
This study's objective was to identify a difference in maximum temperature change during forward versus oscillating drilling of cadaveric bone. Paired femurs were dissected from the soft tissue of five cadavers. Each cadaver had one femur assigned to forward and the other to oscillation. The first drill hole was 2.5 cm distal to the lesser trochanter and the remaining 10 holes were evenly spaced 2 cm apart. A System 7 drill and 3.5 mm drill bit were attached to an Instron 5500R to provide a progressive force of 50 Newtons per minute for each drill hole. A thermal camera recorded each drilling. A new drill bit was used for each femur. Fifty bicortical drillings were analyzed in each group. The average time to complete forward drilling (45.0 seconds) was shorter compared to oscillation (55.5 s, p < 0.001). The average force required for forward drilling (27.7 N) was lower than for oscillation (44.3N, p < 0.001). The maximum change in temperature during the drilling process was similar (oscillating 100.2° F vs. forward 100.7° F, p = 0.871). The maximum change in temperature at the near cortex was lower for oscillation (78.1°F) compared to forward drilling (89.1°F, p = 0.011), while the maximum change at the far cortex was lower for forward drilling (89.3°F) compared to oscillation (95.8°F, p = 0.115) but not significantly. Overall, there is no difference in the thermal output between techniques. Oscillation may be beneficial in proximity to vital structures or to navigate narrow bony corridors, but it requires additional time and force. (Journal of Surgical Orthopaedic Advances 31(4):233-236, 2022).
- Published
- 2022
9. Rethinking the Coronal Anatomic Axis of the Distal Tibia for Intramedullary Nail Placement: A Cadaveric Study.
- Author
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Aneja A, Marquez-Lara A, Luo TD, Teasdall RJ, Isla A, Albano A, Halvorson JJ, and Carroll EA
- Abstract
Background: Recent studies have reported that targeting a center-center position at the distal tibia during intramedullary nailing (IMN) may result in malalignment. Although not fully understood, this observation suggests that the coronal anatomic center of the tibia may not correspond to the center of the distal tibia articular surface. Questions/Purposes : To identify the coronal anatomic axis of the distal tibia that corresponds to an ideal start site for IMN placement utilizing intact cadaveric tibiae. Methods : IMN placement was performed in 9 fresh frozen cadaveric tibiae. A guidewire was used to identify the ideal start site in the proximal tibia and an opening reamer allowed access to the canal. Each nail was then advanced without the use of a reaming rod until exiting the distal tibia plafond. Cadaveric and radiographic measurements were performed to determine the center of the nail exit site in the coronal plane. Results : Cadaveric and radiographic measurements identified the IMN exit site to correspond with the lateral 59.5% and 60.4% of the plafond, respectively. Conclusions : Tibial nails inserted using an ideal start site have an endpoint that corresponds roughly to the junction of the lateral and middle third of the plafond. Further studies are warranted to better understand the impact of IMN endpoint placement on the functional and radiographic outcomes of tibia shaft fractures., Competing Interests: Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Alejandro Marquez-Lara, MD, PhD; T. David Luo, MD; Robert J. Teasdall, MD; Alexander Isla, BS; Ashley Albano, BA; and Jason J. Halvorson, MD, declare that they have no conflicts of interest. Arun Aneja, MD, PhD, is a paid consultant for DePuy Synthes and receives research support from the OTA and AO North America, outside the submitted work. Eben A. Carroll, MD, is a paid consultant and receives research support from DePuy Synthes and Smith and Nephew, outside the submitted work., (© The Author(s) 2021.)
- Published
- 2022
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10. Verification of High-Rate Vertical Loading Laboratory Skeletal Fractures by Comparison with Theater Injury Patterns.
- Author
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Danelson KA, Polich JG, Barnes DR, Bullock GS, Scott AT, Halvorson JJ, O'Gara T, Pilson HT, Babcock S, Birkedal J, McAllister B, and Loftis KL
- Subjects
- Explosions, Humans, Laboratories, Manikins, Operating Rooms, Reproducibility of Results, Blast Injuries, Fractures, Bone, Lower Extremity injuries, Pelvis injuries, Spinal Injuries
- Abstract
For the current study, an existing theater injury data set was compared to component and whole body experiments meant to replicate the theater high rate vertical loading environment. The theater injury data set was derived from real world events that were within the design range of the Warrior Injury Assessment Manikin. A qualitative and quantitative assessment of the whole body fracture patterns was developed to determine whether the laboratory loading was correctly representing the resulting injuries seen in theater Underbody Blast (UBB) events. Results indicated that most of the experimental test fracture patterns were similar to the theater injuries for Abbreviated Injury Scale body regions of interest (lower extremities, pelvis, and spine); however, some of the body regions had higher similarity scores compared to others. Whole body fracture distribution was less similar than the component tests because of differences in injury distributions. The lower extremity whole body similarity was lower than spine and pelvis similarity. This analysis was able to identify some experimental tests that might not represent theater loading. In conclusion, this analysis confirmed that some laboratory testing produced skeletal injury patterns that are seen in comparable theater UBB events., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)
- Published
- 2021
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11. Advances in Geriatric Hip Fractures: Pre-Operative Considerations and Tips to Optimize Outcome.
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Marenghi NM, Tyler-Paris Pilson H, and Halvorson JJ
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- Aged, Humans, Incidence, Morbidity, Anesthesia, Conduction, Hip Fractures surgery
- Abstract
Summary: Geriatric hip fractures are complicated by increased morbidity and mortality, and their incidence continues to rise around the world. Frequent considerations in treating geriatric hip fractures include optimal time to surgery, need for preoperative cardiac clearance, risks of operating through anticoagulation, utilization of regional anesthesia, and collaborative care between treatment teams. This article aims to summarize these factors as well as to provide some tips and tricks that can be helpful in their surgical management., Competing Interests: The authors report no conflict of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2021
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12. Effect of Intrawound Vancomycin Powder in Operatively Treated High-risk Tibia Fractures: A Randomized Clinical Trial.
- Author
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O'Toole RV, Joshi M, Carlini AR, Murray CK, Allen LE, Huang Y, Scharfstein DO, O'Hara NN, Gary JL, Bosse MJ, Castillo RC, Bishop JA, Weaver MJ, Firoozabadi R, Hsu JR, Karunakar MA, Seymour RB, Sims SH, Churchill C, Brennan ML, Gonzales G, Reilly RM, Zura RD, Howes CR, Mir HR, Wagstrom EA, Westberg J, Gaski GE, Kempton LB, Natoli RM, Sorkin AT, Virkus WW, Hill LC, Hymes RA, Holzman M, Malekzadeh AS, Schulman JE, Ramsey L, Cuff JAN, Haaser S, Osgood GM, Shafiq B, Laljani V, Lee OC, Krause PC, Rowe CJ, Hilliard CL, Morandi MM, Mullins A, Achor TS, Choo AM, Munz JW, Boutte SJ, Vallier HA, Breslin MA, Frisch HM, Kaufman AM, Large TM, LeCroy CM, Riggsbee C, Smith CS, Crickard CV, Phieffer LS, Sheridan E, Jones CB, Sietsema DL, Reid JS, Ringenbach K, Hayda R, Evans AR, Crisco MJ, Rivera JC, Osborn PM, Kimmel J, Stawicki SP, Nwachuku CO, Wojda TR, Rehman S, Donnelly JM, Caroom C, Jenkins MD, Boulton CL, Costales TG, LeBrun CT, Manson TT, Mascarenhas DC, Nascone JW, Pollak AN, Sciadini MF, Slobogean GP, Berger PZ, Connelly DW, Degani Y, Howe AL, Marinos DP, Montalvo RN, Reahl GB, Schoonover CD, Schroder LK, Vang S, Bergin PF, Graves ML, Russell GV, Spitler CA, Hydrick JM, Teague D, Ertl W, Hickerson LE, Moloney GB, Weinlein JC, Zelle BA, Agarwal A, Karia RA, Sathy AK, Au B, Maroto M, Sanders D, Higgins TF, Haller JM, Rothberg DL, Weiss DB, Yarboro SR, McVey ED, Lester-Ballard V, Goodspeed D, Lang GJ, Whiting PS, Siy AB, Obremskey WT, Jahangir AA, Attum B, Burgos EJ, Molina CS, Rodriguez-Buitrago A, Gajari V, Trochez KM, Halvorson JJ, Miller AN, Goodman JB, Holden MB, McAndrew CM, Gardner MJ, Ricci WM, Spraggs-Hughes A, Collins SC, Taylor TJ, and Zadnik M
- Subjects
- Adult, Anti-Bacterial Agents administration & dosage, Double-Blind Method, Female, Fracture Fixation, Internal adverse effects, Fractures, Ununited etiology, Humans, Intra-Articular Fractures surgery, Male, Middle Aged, Powders, Probability, Prospective Studies, Surgical Wound Dehiscence etiology, Surgical Wound Infection etiology, Time Factors, Vancomycin administration & dosage, Anti-Bacterial Agents therapeutic use, Gram-Negative Bacterial Infections prevention & control, Gram-Positive Bacterial Infections prevention & control, Surgical Wound Infection prevention & control, Tibial Fractures surgery, Vancomycin therapeutic use
- Abstract
Importance: Despite the widespread use of systemic antibiotics to prevent infections in surgically treated patients with fracture, high rates of surgical site infection persist., Objective: To examine the effect of intrawound vancomycin powder in reducing deep surgical site infections., Design, Setting, and Participants: This open-label randomized clinical trial enrolled adult patients with an operatively treated tibial plateau or pilon fracture who met the criteria for a high risk of infection from January 1, 2015, through June 30, 2017, with 12 months of follow-up (final follow-up assessments completed in April 2018) at 36 US trauma centers., Interventions: A standard infection prevention protocol with (n = 481) or without (n = 499) 1000 mg of intrawound vancomycin powder., Main Outcomes and Measures: The primary outcome was a deep surgical site infection within 182 days of definitive fracture fixation. A post hoc comparison assessed the treatment effect on gram-positive and gram-negative-only infections. Other secondary outcomes included superficial surgical site infection, nonunion, and wound dehiscence., Results: The analysis included 980 patients (mean [SD] age, 45.7 [13.7] years; 617 [63.0%] male) with 91% of the expected person-time of follow-up for the primary outcome. Within 182 days, deep surgical site infection was observed in 29 of 481 patients in the treatment group and 46 of 499 patients in the control group. The time-to-event estimated probability of deep infection by 182 days was 6.4% in the treatment group and 9.8% in the control group (risk difference, -3.4%; 95% CI, -6.9% to 0.1%; P = .06). A post hoc analysis of the effect of treatment on gram-positive (risk difference, -3.7%; 95% CI, -6.7% to -0.8%; P = .02) and gram-negative-only (risk difference, 0.3%; 95% CI, -1.6% to 2.1%; P = .78) infections found that the effect of vancomycin powder was a result of its reduction in gram-positive infections., Conclusions and Relevance: Among patients with operatively treated tibial articular fractures at a high risk of infection, intrawound vancomycin powder at the time of definitive fracture fixation reduced the risk of a gram-positive deep surgical site infection, consistent with the activity of vancomycin., Trial Registration: ClinicalTrials.gov Identifier: NCT02227446.
- Published
- 2021
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13. Technical Trick: Dual Plate Fixation of Periprosthetic Distal Femur Fractures.
- Author
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Medda S, Kessler RB, Halvorson JJ, Pilson HT, Babcock S, and Carroll EA
- Subjects
- Bone Plates, Femur, Fracture Fixation, Internal, Humans, Arthroplasty, Replacement, Knee, Femoral Fractures diagnostic imaging, Femoral Fractures surgery, Periprosthetic Fractures diagnostic imaging, Periprosthetic Fractures surgery
- Abstract
Summary: Treatment of periprosthetic distal femur fractures remains challenging due to assuring adequate distal fixation. Traditional treatment options include lateral locked plating and retrograde nailing, although recently dual implant constructs have been explored with promising results. Allowing immediate weight-bearing in this patient population has benefits with regards to rehabilitation and outcome. Recent literature has focused on nail-plate constructs, however plate-plate constructs are preferred at our institution as they do not require arthroplasty component compatibility, facilitate the coronal plane reduction, and allow for immediate weight-bearing., Competing Interests: S. Medda holds stock in Clovis Oncology and has received educational support from Zimmer Biomet. J. J. Halvorson is a consultant for Smith and Nephew. H. T. Pilson is a paid presenter for Medtronic. E. A. Carroll is a consultant for DePuy Synthes, Smith and Nephew, and Globus and receives research support from DePuy Synthes and Smith and Nephew. The remaining authors report no conflict of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2021
- Full Text
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14. Economic impact of orthopaedic care for non-fatal gunshot wounds: analysis of a public health crisis.
- Author
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Rosas S, Gwam CU, Araiza ET, Roche MW, Emory CL, Carroll EA, Halvorson JJ, and Plate JF
- Abstract
Background: The purpose of this study was to perform an epidemiological evaluation and an economic analysis of 90-day costs associated with non-fatal gunshot wounds (GSWs) to the extremities, spine and pelvis requiring orthopaedic care in the United States., Methods: A retrospective epidemiological review of the Medicare national patient record database was conducted from 2005 to 2014. Incidence, fracture location and costs associated where evaluated. Those patients identified through International Classification of Disease (ICD)-9 revision codes and Current Procedural Terminology (CPT) Codes who sustained a fracture secondary to a GSW. Any type of surgical intervention including incision and drainage, open reduction with internal fixation, closed reduction and percutaneous fixation, etc. were identified to analyze, and evaluate costs of care as seen by charges and reimbursements to the payer. The 90-day period after initial fracture care was queried., Results: A total of 9,765 patients required surgical orthopaedic care for GSWs. There was a total of 2,183 fractures due to GSW treated operatively in 2,201 patients. Of these, 22% were femur fractures, 18.3% were hand/wrist fractures and 16.7% were ankle/foot fractures. A majority of patients were male (83.3%) and under 65 years of age (56.3%). Total charges for GSW requiring orthopedic care were $513,334,743 during the 10-year study period. Total reimbursement for these patients were $124,723,068. Average charges per patient were highest for fracture management of the spine $431,021.33, followed by the pelvis $392,658.45 and later by tibia/fibula fractures $342,316.92., Conclusions: The 90-day direct charges and reimbursements of orthopedic care for non-fatal GSWs are of significant amounts per patient. While the number of fatal GSWs has received much attention, non-fatal GSWs have a large economic and societal impact that warrants further research and consideration by the public and policy makers., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/atm-20-1064). Dr. Roche reports personal fees from Mako stryker, other from CMO orthosensor, other from mako- stryker, Orthosensor, other from makosurgical-stryker, other from Orthosensor, other from Smith & Nephew, outside the submitted work; Dr. Carroll reports personal fees and other from AO Foundation, personal fees and other from AO North America, personal fees and other from DePuy, A Johnson & Johnson Company, personal fees and other from Globus Medical, other from Orthopaedic Trauma Association, personal fees and other from Smith & Nephew, personal fees and other from Synthes, outside the submitted work. Dr. Halvorson reports personal fees and other from Smith & Nephew, outside the submitted work; Dr. Emory reports other from AAOS, other from AAOS Now, other from American Orthopaedic Association, other from Eastern Orthopaedic Association, other from Heron Therapeutics, other from Musculoskeletal Tumor Society, other from Ruth Jackson Orthopaedic Society, other from Southern Orthopaedic Association, outside the submitted work. The other authors have no conflicts of interest to declare., (2021 Annals of Translational Medicine. All rights reserved.)
- Published
- 2021
- Full Text
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15. Technical Trick: The Trochanteric Hook Plate in Treatment of B1 Periprosthetic Femur Fractures.
- Author
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Medda S, Snoap T, Pilson HT, Halvorson JJ, and Carroll EA
- Subjects
- Bone Plates, Femur, Fracture Fixation, Internal, Humans, Treatment Outcome, Arthroplasty, Replacement, Hip, Femoral Fractures surgery, Periprosthetic Fractures surgery
- Abstract
Vancouver B1 periprosthetic fractures undergoing operative fixation remain difficult to treat due to a short proximal segment that offers limited options for fixation. The trochanteric hook plate addresses this issue by maximizing proximal purchase and utilizing the entire lateral surface area of the greater trochanter. A surgical technique that prioritizes proximal fixation and adheres to basic principles resulted in all fractures healing in a small case series. (Journal of Surgical Orthopaedic Advances 29(4):199-201, 2020).
- Published
- 2020
16. Reconstruction of Distal Humerus Fractures with Severe Bone Loss: A Case Series and Review of the Literature.
- Author
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Tipton S, Nunez FA, Vazquez FAN, Halvorson JJ, and Carroll EA
- Subjects
- Adult, Bone Plates, Fracture Fixation, Internal, Humans, Humerus diagnostic imaging, Humerus surgery, Middle Aged, Range of Motion, Articular, Retrospective Studies, Treatment Outcome, Young Adult, Elbow Joint, Fractures, Bone
- Abstract
The objective of this study was to describe examples and review the literature of distal humerus fracture reconstruction in the setting of severe bone loss. Four individuals (ages 19-59 years) were treated with either fibular strut allograft or fresh frozen osteochondral allograft in the setting of unreconstructable periarticular bone loss. The radiographs were evaluated for evidence of union. Pain and degrees of range of motion were reported when available. The follow-up period ranged from 3 to 42 months. While additional surgery was often needed, union was ultimately obtained in each case. Normal range of motion was not obtained, but two of the four patients were near normal upon union. Two of the four patients were pain free, and the other two had mild pain. All were limited in their activities, even after union. This case series describes satisfactory results with the use of allograft in this difficult clinical problem. (Journal of Surgical Orthopaedic Advances 29(2):65-72, 2020).
- Published
- 2020
17. Comparing the Efficiency, Radiation Exposure, and Accuracy Using C-Arm versus O-Arm With 3D Navigation in Placement of Transiliac-Transsacral and Iliosacral Screws: A Cadaveric Study Evaluating an Early Career Surgeon.
- Author
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Araiza ET, Medda S, Plate JF, Marquez-Lara A, Trammell AP, Aran FS, Lara D, Danelson K, Halvorson JJ, Carroll EA, and Pilson HT
- Subjects
- Bone Screws, Cadaver, Humans, Imaging, Three-Dimensional, Sacrum diagnostic imaging, Sacrum surgery, Tomography, X-Ray Computed, Radiation Exposure prevention & control, Surgeons, Surgery, Computer-Assisted
- Abstract
Objectives: To compare the efficiency, radiation exposure to surgeon and patient, and accuracy of C-arm versus O-arm with navigation in the placement of transiliac-transsacral and iliosacral screws by an orthopaedic trauma fellow, for a surgeon early in practice., Methods: Twelve fresh frozen cadavers were obtained. Preoperative computed tomography scans were reviewed to assess for safe corridors in the S1 and S2 segments. Iliosacral screws were assigned to the S1 segment in dysmorphic pelvises. Screws were randomized to modality and laterality. An orthopaedic trauma fellow placed all screws. Time of procedure and radiation exposure to the cadaver and surgeon were recorded. Three fellowship-trained orthopaedic trauma surgeons rated the safety of each screw on postoperative computed tomography scan., Results: Six normal and 6 dysmorphic pelvises were identified. Eighteen transiliac-transsacral screws and 6 iliosacral screws were distributed evenly between C-arm and O-arm. Average operative duration per screw was significantly shorter using C-arm compared with O-arm (15.7 minutes ± 6.1 vs. 23.7 ± 8.5, P = 0.014). Screw placement with C-arm exposed the surgeon to a significantly greater amount of radiation (3.87 × 10 rads vs. 0.32 × 10, P < 0.001) while O-arm exposed the cadaver to a significantly greater amount of radiation (0.03 vs. 2.76 rads, P < 0.001). Two S2 transiliac-transsacral screws (1 C-arm and 1 O-arm) were categorized as unsafe based on scoring. There was no difference in screw accuracy between modalities., Conclusions: A difference in accuracy between modalities could not be elucidated, whereas efficiency was improved with utilization of C-arm, with statistical significance. A statistically significant increase in radiation exposure to the surgeon using C-arm was found, which may be clinically significant over a career. The results of this study can be extrapolated to a fellow or surgeon early in practice. The decision between use of these modalities will vary depending on surgeon preference and hospital resources.
- Published
- 2020
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18. Negative-Pressure Wound Therapy in Foot and Ankle Surgery.
- Author
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Kunze KN, Hamid KS, Lee S, Halvorson JJ, Earhart JS, and Bohl DD
- Subjects
- Humans, Ankle surgery, Foot surgery, Negative-Pressure Wound Therapy methods, Surgical Wound therapy, Wound Healing physiology
- Abstract
Negative Pressure Wound Therapy (NPWT) is frequently utilized to manage complex wounds, however its mechanisms of healing remain poorly understood. Changes in growth factor expression, micro- and macro-deformation, blood flow, exudate removal, and bacterial concentration within the wound bed are thought to play a role. NPWT is gaining widespread usage in foot and ankle surgery, including the management of traumatic wounds; diabetic and neuropathic ulcers; wounds left open after debridement for infection or dehiscence; high-risk, closed incisions; tissue grafts and free flaps. This article reviews the rationale for NPWT, its proposed mechanisms of action, and the evidence regarding its clinical applications within the field of foot and ankle surgery. Level of Evidence: Level V, expert opinion.
- Published
- 2020
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19. Valgus Intertrochanteric Osteotomy for Femoral Neck Nonunion.
- Author
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Medda S, Jinnah AH, Marquez-Lara A, Araiza ET, Hasty EK, Halvorson JJ, and Pilson HT
- Subjects
- Humans, Femoral Neck Fractures surgery, Femur Neck surgery, Fracture Fixation, Internal methods, Fracture Healing, Fractures, Ununited surgery, Osteotomy methods
- Abstract
Valgus intertrochanteric osteotomy is an effective method of treating femoral neck nonunion by reducing shear forces at the fracture and correcting the neck-shaft angle. Good outcomes have been reported in the literature. Through careful preoperative planning and a precise operative technique, reliable healing of both the osteotomy and nonunion can be achieved.
- Published
- 2019
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20. Treatment of Peritrochanteric Femur Fractures With Proximal Femur Locked Plating.
- Author
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Medda S, Sullivan RJ, Marquez-Lara A, Araiza ET, Pilson HT, Halvorson JJ, and Carroll EA
- Subjects
- Bone Screws, Femoral Fractures diagnosis, Follow-Up Studies, Humans, Radiography, Retrospective Studies, Bone Plates, Femoral Fractures surgery, Fracture Fixation, Internal methods, Fracture Healing
- Abstract
Objectives: To report on our results using a proximal femoral locking plate for the treatment of peritrochanteric femur fractures., Design: Retrospective study., Setting: Level I Academic Medical Center., Patients: Sixty-eight patients with 68 fractures., Intervention: Demographics, fracture morphology, preoperative imaging, rationale against nailing, and outcomes were collected., Main Outcome Measurements: Outcomes were grouped into no complication, minor complication, or major complication. Minor complications included healed fractures with implant failure or change in alignment from immediate postoperative radiographs, which did not require intervention or elective implant removal. Major complications included any case that required revision for nonunion or implant failure., Results: Nine patients were lost to follow-up. Of the 59 fractures, 16 had complications (27%): 9 minor and 7 major. Active tobacco use (P = 0.020) and fractures with an associated intracapsular femoral neck component (P = 0.006) correlated with complications., Conclusions: Proximal femoral locking plates continue to be associated with a high complication rate. However, based on our experience, proximal femoral locking plates may be considered in highly selected cases when absolutely no other implant is deemed appropriate, based on the degree of comminution and the complexity of the fracture pattern. Patients must be informed about the possibility of revision surgery based on the inherent limitations of these devices., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
- Published
- 2019
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21. Systemic Change for Value-Based Care in Orthopaedic Trauma.
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Rosas S, Gwam CU, Emory CL, Pilson HT, Halvorson JJ, and Carroll EA
- Subjects
- Humans, Patients, Trauma Centers, Orthopedics
- Published
- 2019
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22. Biomechanical Evaluation of Interfragmentary Compression of Lag Screw Versus Positional Screw at Different Angles of Fixation.
- Author
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Kuzma AL, Luo TD, De Gregorio M, Coon GD, Danelson K, Halvorson JJ, Carroll EA, and Aneja A
- Subjects
- Humans, Pressure, Bone Screws, Compressive Strength, Fracture Fixation, Internal methods, Humeral Fractures surgery, Materials Testing methods
- Abstract
Objectives: To compare the compressive force achieved and retained with the lag versus positional screw technique at various angles of screw application., Methods: Sixty humeral sawbones were stratified into 6 groups based on the technique (lag or positional) and fixation angle (30, 60, or 90 degrees relative to the fracture plane). A sensor was placed between fragments to record compressive force. Absolute screw force is the final screw force. Normalized force is the final screw force minus force generated by reduction forceps. Retained force is the quotient of absolute force relative to reduction forceps force., Results: Lag screws attained higher force than positional at 60 degrees (absolute force 41% higher, P = 0.041; normalized force 1300% higher, P = 0.008; retained force 60% higher, P = 0.008) and 90 degrees (absolute force 86% higher, P = 0.006; normalized force 730% higher, P = 0.005; retained force 70% higher, P = 0.011), but not at 30 degrees. For lag screws, compressive force was similar at 60 and 90 degrees (absolute force P = 0.174, normalized force P = 0.364, and retained force P = 0.496), but not 30 degrees. For positional screws, no difference was found between the 3 angles of fixation for absolute force (P = 0.059). Normalized force and retained force were similar at 60 and 90 degrees (P = 0.944 and P = 0.725, respectively), but not 30 degrees., Conclusions: Lag screw technique compressive force was superior to positional screw technique at 60 and 90 degrees. Comparison of force at angles of 60 and 90 degrees showed no significant difference for both techniques. Indicating 30 degrees deviation from perfect technique is tolerated without significant decrease in compressive force.
- Published
- 2019
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23. Simulated Soil Organic Carbon Responses to Crop Rotation, Tillage, and Climate Change in North Dakota.
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Nash PR, Gollany HT, Liebig MA, Halvorson JJ, Archer DW, and Tanaka DL
- Subjects
- Agriculture, Crops, Agricultural, North Dakota, Carbon, Climate Change, Crop Production, Soil chemistry
- Abstract
Understanding how agricultural management and climate change affect soil organic carbon (SOC) stocks is particularly important for dryland agriculture regions that have been losing SOC over time due to fallow and tillage practices, and it can lead to development of agricultural practice(s) that reduce the impact of climate change on crop production. The objectives of this study were: (i) to simulate SOC dynamics in the top 30 cm of soil during a 20-yr (1993-2012) field study using CQESTR, a process-based C model; (ii) to predict the impact of changes in management, crop production, and climate change from 2013 to 2032; and (iii) to identify the best dryland cropping systems to maintain or increase SOC stocks under projected climate change in central North Dakota. Intensifying crop rotations was predicted to have a greater impact on SOC stocks than tillage (minimum tillage [MT], no-till [NT]) during 2013 to 2032, as SOC was highly correlated to biomass input ( = 0.91, = 0.00053). Converting from a MT spring wheat (SW, L.)-fallow rotation to a NT continuous SW rotation increased annualized biomass additions by 2.77 Mg ha (82%) and SOC by 0.22 Mg C ha yr. Under the assumption that crop production will stay at the 1993 to 2012 average, climate change is predicted to have a minor impact on SOC (approximately -6.5%) relative to crop rotation management. The CQESTR model predicted that the addition of another SW or rye ( L.) crop would have a greater effect on SOC stocks (0- to 30-cm depth) than conversion from MT to NT or climate change from 2013 to 2032., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)
- Published
- 2018
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24. Coronal Plane Deformity Correction in Distal Radius Fracture Fixation With the Volar Locking Plate.
- Author
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Aneja A, Luo TD, Lerche EB, Halvorson JJ, and Carroll EA
- Subjects
- Adult, Female, Humans, Bone Plates, Fracture Fixation, Internal methods, Radius Fractures surgery
- Abstract
The goal of treatment for distal radius fractures is anatomic articular reduction and restoration of coronal and sagittal plane alignment, rotation, and angulation of the metadiaphyseal component of these fractures. This article presents a reproducible technique for restoring coronal plane alignment of the metadiaphyseal component of the fracture using an indirect reduction maneuver leveraging the volar locking plate as an indirect reduction aid. After applying an appropriately sized volar locking plate, the first screw is placed in the center of the shaft of the plate. Next, the distal row of subarticular locking screws is placed to neutralize a reduced articular surface. The shaft screw is subsequently loosened, and two Freer elevators are used to rotate the plate, indirectly translating the distal articular block and achieving improved coronal plane alignment. Last, the remaining diaphyseal screws are applied to appropriately neutralize the fracture. (Journal of Surgical Orthopaedic Advances 27(2):160-163, 2018).
- Published
- 2018
25. Anterolateral distal tibia locking plate osteosynthesis and their ability to capture OTAC3 pilon fragments.
- Author
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Aneja A, Luo TD, Liu B, Domingo M 4th, Danelson K, Halvorson JJ, and Carroll EA
- Subjects
- Biomechanical Phenomena, Bone Plates, Bone Screws, Fractures, Comminuted diagnostic imaging, Humans, Materials Testing, Simulation Training, Tibial Fractures diagnostic imaging, Tomography, X-Ray Computed, Torsion, Mechanical, Artificial Organs, Bone and Bones, Fracture Fixation, Internal, Fractures, Comminuted surgery, Tibial Fractures surgery
- Abstract
Background: Intra-articular Pilon fractures remain therapeutically challenging due to osteochondral fracturing and comminution, marginal impaction, and insult to the soft tissue envelope. The purpose of this study was to compare the efficacy of anterolateral distal tibial locking plates in capturing main fracture fragments in tibial plafond fractures., Methods: From May 2011 to Dec 2015, 169 OTA C-type pilon fractures met inclusion and exclusion criteria with computed tomographic (CT) scans performed prior to definitive fixation. For each patient, the fracture lines were mapped, digitized, and graphically superimposed to create a compilation of fracture lines. Based on these average measurements, three distal tibia sawbones had three different anterolateral plates applied. Axial CT scan images were used to determine the efficacy of screw purchase in main fracture fragments in pilon fractures., Results: The Smith & Nephew PERI-LOC plate secured the largest number of fracture lines (90.1%) but missed the Volkmann fragment with greatest frequency at 3.6%. The Synthes 2.7/3.5 mm VA-LCP captured 87.3% of the fracture lines while missing the Volkmann fragment 3.2% of the time. The Synthes 3.5 mm LCP captured 86.5% of the fracture lines but was the best at securing the Volkmann fragment (1.2% missed). All three implants were deficient in capturing the medial malleolar fragment. The PERI-LOC and 2.7/3.5 mm VA-LCP did not differ with respect to percentage of fragments captured (p = 0.721) but both outperformed the 3.5 mm LCP (p = 0.021 and p = 0.05, respectively)., Conclusions: This study was consistent with prior literature in defining three main fracture fragments: anterior, medial, and posterior. All three plates were deficient in capturing the medial malleolar fragment. The Smith and Nephew PERI-LOC plate secured the most number of fracture lines, while the Synthes 3.5 mm LCP was least likely to miss the Volkmann fragment and most likely to miss the medial malleolar fragment. No plate was found to be superior to the other in capturing all fracture lines of the OTAC3 pilon fragments., Level of Evidence: Three., (Published by Elsevier Ltd.)
- Published
- 2018
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26. Effects of dietary tannins on total and extractable nutrients from manure.
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Halvorson JJ, Kronberg SL, and Hagerman AE
- Subjects
- Animals, Diet veterinary, Feces chemistry, Lespedeza chemistry, Male, Medicago sativa chemistry, Plant Leaves chemistry, Random Allocation, Tannins administration & dosage, Manure analysis, Sheep physiology, Tannins pharmacology
- Abstract
The effects of condensed tannins on N dynamics in ruminants have been a topic of research for some time, but much less work has focused on their impacts on other nutrients in manure. A 4 × 4 Latin square trial was used to determine if intake of sericea lespedeza (; SL; a condensed tannin source), at 0, 10, 20, or 40% of the diet (as-fed basis), would affect concentrations of nutrients in manure and patterns of total excretion when offered with alfalfa (; ALF) to sheep. With SL additions, average daily manure production increased linearly ( ≤ 0.01), from 40 to 50% of the diet mass. The concentrations of total C, total N, soluble P, total and soluble Na, total and soluble S, total and soluble Mn, and total and soluble B in feces increased ( ≤ 0.05) while soluble N, total Ca, total and soluble Mg, soluble Zn, total and soluble Fe, total and soluble Cu decreased ( ≤ 0.02). Total P, total and soluble K, soluble Ca, and total Zn were less affected ( > 0.05). Comparing diets containing 0 to 40% SL, average daily outputs of total C, total N, soluble P, soluble K, total and soluble Na, and total Mn increased linearly ( ≤ 0.01) by 42.0, 71.2, 93.3, 45.2, 111, 148, and 52.4 percentage points, respectively. Total K, total and soluble S, soluble Mn, and total and soluble B increased quadratically ( ≤ 0.02) by 26.1, 52.3, 26.7, 147, 100, and 19.5 percentage points, respectively. Conversely, outputs of soluble Zn and total Fe decreased linearly ( ≤ 0.01), by -51.5 and -24.8 percentage points, while total Ca, total and soluble Mg, soluble Fe, and soluble Cu decreased quadratically ( ≤ 0.05) by -15.7, -12.3, -40.0, -89.9, and -60.3 percentage points, respectively. Outputs of soluble N, total P, soluble Ca, total Zn, and total Cu remained unchanged ( ≥ 0.14). Ratios of manure outputs to feed inputs for C, N, K, and B increased ( ≤ 0.02) but those for P and Mg were unchanged ( ≥ 0.10). Ratios of soluble to total manure outputs (S:O) increased ( ≤ 0.01) for P, Ca, Na, Mn; decreased ( ≤ 0.05) for N, S, Mg, Zn, Fe, Cu, and B; and were unaffected by treatment ( ≤ 0.16) for K. Decreasing S:O ratios are consistent with the formation of complexes that adsorb these nutrients to insoluble fiber fractions of manure and could thus affect mineralization rates. This study suggests that dietary tannins, found in forages like SL, can alter the concentrations, total excretion rates and throughput efficiency of nutrients in manure.
- Published
- 2017
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27. Finding Value in Surgical Didactics: Longitudinal Resident Feedback From Case-Based and Traditional Lectures in an Orthopaedic Residency.
- Author
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Barnwell JC, Halvorson JJ, Teasdall RD, and Carroll EA
- Subjects
- Adult, Attitude of Health Personnel, Cohort Studies, Competency-Based Education, Education, Medical, Graduate organization & administration, Female, Humans, Logistic Models, Longitudinal Studies, Male, Odds Ratio, Program Evaluation, Prospective Studies, Clinical Competence, Curriculum, Feedback, Internship and Residency organization & administration, Orthopedics education
- Abstract
Objective: To evaluate orthopedic resident perceptions of a didactic curriculum presented in traditional and case-based formats., Design: Prospective cohort study using anonymous web-based survey after each conference evaluating resident perceptions of faculty participation, didactic delivery, content, and overall conference value. Conferences were structured as primarily case-based or traditional lecture. Logistic analysis was performed to determine factors predictive of rating a conference as valuable time spent., Setting: Orthopedic residency training program at single institution over an academic year., Participants: Orthopedic residents in postgraduate training year 1 to 5 attending mandatory didactic conference., Results: Cased-based conferences received higher Likert ratings on residents' perception of faculty participation, instructor delivery, and improvement in topic understanding when compared to traditional lecture-based conferences (p < 0.0001 for each factor). Residents also were more likely to rate case-based conferences as valuable time spent (p < 0.0001). In our logistic model, factors associated with a negative likelihood of rating a conference as valuable were lecture format (odds ratio [OR] = 0.155, 95% CI: 0.115-0.208), PGY-2 level presenter (OR = 0.288, 95% CI: 0.169-0.490), and PGY-3 level presenter (OR = 0.433, 95% CI: 0.269-0.696). Timing in the year, surgical subspeciality, and conference identity were not significant predictors of conference value rating., Conclusions: Longitudinal resident feedback demonstrates highly favorable resident perceptions toward case-based formats in didactic sessions. Junior levels residents are not perceived as effective as senior residents and faculty in presenting material in either format. These methods allow for a dynamic approach to identifying strengths and weaknesses in a resident curriculum as a well as a means for more focused and real-time improvements., (Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
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28. Polyphenol-Aluminum Complex Formation: Implications for Aluminum Tolerance in Plants.
- Author
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Zhang L, Liu R, Gung BW, Tindall S, Gonzalez JM, Halvorson JJ, and Hagerman AE
- Subjects
- Aluminum analysis, Aluminum metabolism, Eucalyptus metabolism, Gallic Acid analogs & derivatives, Gallic Acid chemistry, Hydrogen-Ion Concentration, Hydrolyzable Tannins chemistry, Molecular Weight, Polyphenols analysis, Polyphenols metabolism, Rumex metabolism, Solubility, Aluminum chemistry, Organometallic Compounds chemistry, Plants metabolism, Polyphenols chemistry
- Abstract
Natural polyphenols may play an important role in aluminum detoxification in some plants. We examined the interaction between Al(3+) and the purified high molecular weight polyphenols pentagalloyl glucose (940 Da) and oenothein B (1568 Da), and the related compound methyl gallate (184 Da) at pH 4 and 6. We used spectrophotometric titration and chemometric modeling to determine stability constants and stoichiometries for the aluminum-phenol (AlL) complexes. The structures and spectral features of aluminum-methyl gallate complexes were evaluated with quantum chemical calculations. The high molecular weight polyphenols formed Al3L2 complexes with conditional stability constants (β) ∼ 1 × 10(23) at pH 6 and AlL complexes with β ∼ 1 × 10(5) at pH 4. Methyl gallate formed AlL complexes with β = 1 × 10(6) at pH 6 but did not complex aluminum at pH 4. At intermediate metal-to-polyphenol ratios, high molecular weight polyphenols formed insoluble Al complexes but methyl gallate complexes were soluble. The high molecular weight polyphenols have high affinities and solubility features that are favorable for a role in aluminum detoxification in the environment.
- Published
- 2016
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29. Combined acetabulum and pelvic ring injuries.
- Author
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Halvorson JJ, Lamothe J, Martin CR, Grose A, Asprinio DE, Wellman D, and Helfet DL
- Subjects
- Fracture Fixation, Internal methods, Fractures, Bone etiology, Humans, Prognosis, Pubic Symphysis injuries, Sacroiliac Joint injuries, Acetabulum injuries, Fractures, Bone surgery, Multiple Trauma surgery, Sacroiliac Joint surgery
- Abstract
Combined fractures of the acetabulum and pelvic ring are more common than previously believed, with an incidence as high as 15.7%. Recent series that include combined injuries indicate that the incidence of lateral compression and anteroposterior compression pelvic ring injuries is similar and that transverse and both-column acetabular fractures are the most common acetabular fracture patterns. Combined injuries most often are the result of high-energy mechanisms, and, compared with patients who present with isolated pelvic or acetabular injury, patients with combined injury typically have higher injury severity scores, higher transfusion requirements, and lower systolic blood pressure, with reported mortality rates of 1.5% to 13%. Treatment requires a multidisciplinary approach. The first priority is resuscitation following the Advanced Trauma Life Support protocols. Once the patient is stable, acetabular fractures and pelvic ring injuries should be assessed individually, and the most appropriate treatment for each should be outlined. These treatments should then be integrated to develop the most appropriate overall treatment strategy. Although outcomes data are available for isolated acetabulum and pelvic ring disruptions, no such data currently exist for combined injuries.
- Published
- 2014
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30. Non-anatomical capsular closure of a standard parapatellar knee arthrotomy leads to patellar maltracking and decreased range of motion: a cadaver study.
- Author
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Plate JF, Seyler TM, Halvorson JJ, Santago AC 2nd, and Lang JE
- Subjects
- Aged, Aged, 80 and over, Arthroplasty, Replacement, Knee adverse effects, Biomechanical Phenomena, Female, Humans, In Vitro Techniques, Male, Middle Aged, Patella surgery, Patellofemoral Joint surgery, Range of Motion, Articular, Rotation, Suture Techniques, Arthroplasty, Replacement, Knee methods, Patella physiopathology, Patellofemoral Joint physiopathology
- Abstract
Purpose: A parapatellar approach disrupts the medial soft tissue stabilizers of the patella. We hypothesized that soft tissue realignment during arthrotomy closure of native cadaveric knees influences patellar kinematics leading to decreased range of motion., Methods: Parapatellar arthrotomy was performed in seven native human cadaveric knees that did not contain arthroplasty components. Capsular closure was performed with figure-of-eight sutures in five different positions for each specimen. The capsule was closed anatomically, and then shifted 1.5 or 3 cm distal, or 1.5 or 3 cm proximal relative to surgical markings of the patellar poles. In each closure position, real-time patellar kinematics and range of motion were recorded using a navigation system with patellar tracking function., Results: Maximum knee flexion was significantly reduced with closure shifted 3 cm proximal (133° ± 8.2°, p < 0.001) or distal (139° ± 6.4°, p < 0.05) compared to anatomical closure (147° ± 4.1°). All closure positions significantly influenced patellar rotation at 45°, 90°, and 120° of flexion (p < 0.001). Closure 1.5 or 3 cm distal increased lateral patellar shift relative to the mechanical axis (p < 0.01). Patellar tilt was significantly decreased at 90° and 120° by closure 3 cm distal (p < 0.01) and at 120° when closed 1.5 cm distal (p < 0.05)., Conclusions: Imprecise arthrotomy closure significantly impacted patellar kinematics and passive range of motion. Therefore, every effort should be made to provide anatomical closure of the extensor mechanism to preserve native patellar movement kinematics., Level of Evidence: V.
- Published
- 2014
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31. Soil microbial communities respond differently to three chemically defined polyphenols.
- Author
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Schmidt MA, Kreinberg AJ, Gonzalez JM, Halvorson JJ, French E, Bollmann A, and Hagerman AE
- Subjects
- Archaea drug effects, Bacteria drug effects, Polyphenols chemistry, Soil Microbiology, Tannins chemistry, Tannins pharmacology, Polyphenols pharmacology
- Abstract
High molecular weight polyphenols (e.g. tannins) that enter the soil may affect microbial populations, by serving as substrates for microbial respiration or by selecting for certain microbes. In this study we examined how three phenolic compounds that represent some environmentally widespread tannins or their constituent functional groups were respired by soil microorganisms and how the compounds affected the abundance and diversity of soil bacteria and archaea, including ammonia oxidizers. An acidic, silt loam soil from a pine forest was incubated for two weeks with the monomeric phenol methyl gallate, the small polyphenol epigallocatechin gallate, or the large polyphenol oenothein B. Respiration of the polyphenols during the incubation was measured using the Microresp™ system. After incubation, metabolic diversity was determined by community level physiological profiling (CLPP), and genetic diversity was determined using denaturing gradient gel electrophoresis (DGGE) analysis on DNA extracted from the soil samples. Total microbial populations and ammonia-oxidizing populations were measured using real time quantitative polymerase chain reaction (qPCR). Methyl gallate was respired more efficiently than the higher molecular weight tannins but not as efficiently as glucose. Methyl gallate and epigallocatechin gallate selected for genetically or physiologically unique populations compared to glucose. None of the polyphenols supported microbial growth, and none of the polyphenols affected ammonia-oxidizing bacterial populations or ammonia-oxidizing archaea. Additional studies using both a wider range of polyphenols and a wider range of soils and environments are needed to elucidate the role of polyphenols in determining soil microbiological diversity., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)
- Published
- 2013
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32. Successful Manubriosternal Fusion Following Failure of Open Reduction and Internal Fixation of a Traumatic Manubriosternal Dislocation: A Case Report.
- Author
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Scott AT, Halvorson JJ, O'Gara TJ, and Lata AL
- Published
- 2013
- Full Text
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33. Distal locking using an electromagnetic field-guided computer-based real-time system for orthopaedic trauma patients.
- Author
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Langfitt MK, Halvorson JJ, Scott AT, Smith BP, Russell GB, Jinnah RH, Miller AN, and Carroll EA
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Computer Systems, Electromagnetic Fields, Equipment Design, Equipment Failure Analysis, Fracture Fixation, Intramedullary methods, Humans, Middle Aged, Prospective Studies, Surgery, Computer-Assisted methods, Treatment Outcome, Young Adult, Femoral Fractures diagnosis, Femoral Fractures surgery, Fracture Fixation, Intramedullary instrumentation, Operative Time, Surgery, Computer-Assisted instrumentation, Tibial Fractures diagnosis, Tibial Fractures surgery
- Abstract
Objectives: To compare the efficacy of distal interlocking during intramedullary nailing using a freehand technique versus an electromagnetic field real-time system (EFRTS)., Design: A prospective, randomized controlled trial., Setting: Level I academic trauma center., Patients/participants: Patients older than 18 years who sustained a femoral or tibial shaft fracture amenable to antegrade intramedullary nailing were prospectively enrolled between August 2010 and November 2011. Exclusion criteria included injuries requiring retrograde nailing and open wounds near the location of the distal interlocks (distal third of the femur, knee, or distal tibia)., Intervention: Each patient had 2 distal interlocking screws placed: one using the freehand method and the other using EFRTS., Main Outcome Measurement: Techniques were compared on procedural time and number of interlocking screw misses. Two time points were measured: time 1 (time to find perfect circles/time from wand placement to drill initiation) and time 2 (drill initiation until completion of interlocking placement)., Results: Twenty-four tibia and 24 femur fractures were studied. EFRTS proved faster at times 1 and 2 (P < 0.0001 and P < 0.0002) and total time (P < 0.0001). This difference was larger for junior residents, though reached statistical significance for senior residents. Senior residents were faster with the freehand technique compared with junior residents (P < 0.004), but the 2 were similar using EFRTS (P = 0.41). The number of misses was higher with free hand compared with EFRTS (P = 0.02)., Conclusion: These results suggest that EFRTS is faster than the traditional freehand technique and results in fewer screw misses., Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
- Published
- 2013
- Full Text
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34. Metal mobilization in soil by two structurally defined polyphenols.
- Author
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Schmidt MA, Gonzalez JM, Halvorson JJ, and Hagerman AE
- Subjects
- Environmental Monitoring, Metals analysis, Models, Chemical, Soil Pollutants analysis, Metals chemistry, Polyphenols chemistry, Soil chemistry, Soil Pollutants chemistry
- Abstract
Polyphenols including tannins comprise a large percentage of plant detritus such as leaf litter, and affect soil processes including metal dynamics. We tested the effects of tannins on soil metal mobilization by determining the binding stoichiometries of two model polyphenols to Al(III) and Fe(III) using micelle-mediated separation and inductively coupled plasma optical emission spectroscopy (ICP-OES). By fitting the data to the Langmuir model we found the higher molecular weight polyphenol (oenothein B) was able to bind more metal than the smaller polyphenol (epigallocatechin gallate, EGCg). For example, oenothein B bound 9.43 mol Fe mol(-1), while EGCg bound 4.41 mol of Fe mol(-1). Using the parameters from the binding model, we applied the Langmuir model for competitive binding to predict binding for mixtures of Al(III) and Fe(III). Using the parameters from the single metal experiments and information about polyphenol sorption to soils we built a model to predict metal mobilization from soils amended with polyphenols. We tested the model with three natural soils and found that it predicted mobilization of Fe and Al with r(2)=0.92 and r(2)=0.88, respectively. The amount of metal that was mobilized was directly proportional to the maximum amount of metal bound to the polyphenol. The secondary parameter in each model was the amount of weak organically chelated Fe or Al that was in the soil. This study provides the first compound-specific information about how natural polyphenols interact with metals in the environment. We propose a model that is applicable to developing phytochelation agents for metal detoxification, and we discuss how tannins may play a role in metal mobilization from soils., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2013
- Full Text
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35. Talar neck fractures: a systematic review of the literature.
- Author
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Halvorson JJ, Winter SB, Teasdall RD, and Scott AT
- Subjects
- Humans, Osteonecrosis etiology, Postoperative Complications, Talus surgery, Treatment Outcome, Fractures, Bone surgery, Talus injuries
- Abstract
Considerable controversy surrounds the management of talar neck fractures regarding the rate of post-traumatic arthrosis, secondary procedures, avascular necrosis, and the effect of the interval to surgery on these variables. A data search using PubMed was performed with the keywords "talus" and "fracture." The search found 1280 studies. Ultimately, 21 reports involving 943 talar neck fractures were analyzed. Data concerning open fractures, the interval to surgery and its relationship to the incidence of avascular necrosis, and the rates of malunion and nonunion, post-traumatic arthrosis, secondary salvage procedures, and functional outcomes were collected and analyzed. The variables examined were not uniformly reported in all studies. The overall rate of avascular necrosis was 33%, with no demonstrated relationship between the interval to surgery and the rate of avascular necrosis. Malunion occurred approximately 17% of the time, with nonunion occurring approximately 5% of the time. Post-traumatic arthrosis occurred in 68% of patients, although secondary salvage procedures were only performed in 19% of patients. Functional outcomes were difficult to assess, given the variability of reported outcomes and unvalidated measures. The optimal management of talar neck fractures has yet to be determined. Although the present review has improved understanding of these difficult fractures, additional studies that use validated outcomes measures are warranted to determine the effect of delayed surgery on final outcomes and optimal treatment methods., (Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
36. Orthopaedic management in the polytrauma patient.
- Author
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Halvorson JJ, Pilson HT, Carroll EA, and Li ZJ
- Subjects
- Clinical Protocols, Diagnostic Imaging, Fractures, Bone diagnosis, Humans, Patient Care Team, Fractures, Bone therapy, Multiple Trauma therapy, Musculoskeletal System injuries, Orthopedics methods
- Abstract
The past century has seen many changes in the management of the polytraumatized orthopaedic patient. Early recommendations for non-operative treatment have evolved into early total care (ETC) and damage control orthopaedic (DCO) treatment principles. These principles force the treating orthopaedist to take into account multiple patient parameters including hypothermia, coagulopathy and volume status before deciding upon the operative plan. This requires a multidisciplinary approach involving critical care physicians, anesthesiologists and others.
- Published
- 2012
- Full Text
- View/download PDF
37. Chicken manure biochar as liming and nutrient source for acid Appalachian soil.
- Author
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Hass A, Gonzalez JM, Lima IM, Godwin HW, Halvorson JJ, and Boyer DG
- Subjects
- Animals, Appalachian Region, Hydrogen-Ion Concentration, Temperature, Charcoal, Chickens, Manure, Soil chemistry
- Abstract
Acid weathered soils often require lime and fertilizer application to overcome nutrient deficiencies and metal toxicity to increase soil productivity. Slow-pyrolysis chicken manure biochars, produced at 350 and 700°C with and without subsequent steam activation, were evaluated in an incubation study as soil amendments for a representative acid and highly weathered soil from Appalachia. Biochars were mixed at 5, 10, 20, and 40 g kg into a Gilpin soil (fine-loamy, mixed, active, mesic Typic Hapludult) and incubated in a climate-controlled chamber for 8 wk, along with a nonamended control and soil amended with agronomic dolomitic lime (AgLime). At the end of the incubation, soil pH, nutrient availability (by Mehlich-3 and ammonium bicarbonate diethylene triamine pentaacetic acid [AB-DTPA] extractions), and soil leachate composition were evaluated. Biochar effect on soil pH was process- and rate-dependent. Biochar increased soil pH from 4.8 to 6.6 at the high application rate (40 g kg), but was less effective than AgLime. Biochar produced at 350°C without activation had the least effect on soil pH. Biochar increased soil Mehlich-3 extractable micro- and macronutrients. On the basis of unit element applied, increase in pyrolysis temperature and biochar activation decreased availability of K, P, and S compared to nonactivated biochar produced at 350°C. Activated biochars reduced AB-DTPA extractable Al and Cd more than AgLime. Biochar did not increase NO in leachate, but increased dissolved organic carbon, total N and P, PO, SO, and K at high application rate (40 g kg). Risks of elevated levels of dissolved P may limit chicken manure biochar application rate. Applied at low rates, these biochars provide added nutritional value with low adverse impact on leachate composition., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)
- Published
- 2012
- Full Text
- View/download PDF
38. Management of humeral shaft fractures.
- Author
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Carroll EA, Schweppe M, Langfitt M, Miller AN, and Halvorson JJ
- Subjects
- External Fixators, Fracture Fixation, Intramedullary, Fractures, Ununited surgery, Humans, Humeral Fractures complications, Humeral Fractures diagnostic imaging, Patient Selection, Physical Examination, Radial Neuropathy etiology, Radial Neuropathy therapy, Radiography, Fracture Fixation, Internal, Humeral Fractures surgery
- Abstract
Humeral shaft fractures account for approximately 3% of all fractures. Nonsurgical management of humeral shaft fractures with functional bracing gained popularity in the 1970s, and this method is arguably the standard of care for these fractures. Still, surgical management is indicated in certain situations, including polytraumatic injuries, open fractures, vascular injury, ipsilateral articular fractures, floating elbow injuries, and fractures that fail nonsurgical management. Surgical options include external fixation, open reduction and internal fixation, minimally invasive percutaneous osteosynthesis, and antegrade or retrograde intramedullary nailing. Each of these techniques has advantages and disadvantages, and the rate of fracture union may vary based on the technique used. A relatively high incidence of radial nerve injury has been associated with surgical management of humeral shaft fractures. However, good surgical outcomes can be achieved with proper patient selection.
- Published
- 2012
- Full Text
- View/download PDF
39. Risk of septic knee following retrograde intramedullary nailing of open and closed femur fractures.
- Author
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Halvorson JJ, Barnett M, Jackson B, and Birkedal JP
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Bone Nails adverse effects, Female, Follow-Up Studies, Fracture Fixation, Intramedullary instrumentation, Humans, Male, Middle Aged, Prosthesis-Related Infections etiology, Risk Assessment methods, Young Adult, Arthritis, Infectious etiology, Femoral Fractures surgery, Fracture Fixation, Intramedullary methods, Fractures, Open surgery, Knee Joint
- Abstract
Background: One potential complication of retrograde femoral nailing in the treatment of femur fractures is the risk of septic knee. This risk theoretically increases in open fractures as a contaminated fracture site has the potential to seed the instrumentation being passed in and out of the sterile intraarticular starting point. There are few studies examining this potential complication in a relatively commonly practiced technique., Methods: All patients who received a retrograde femoral nail for femur fracture between September 1996 and November 2006 at a Level 1 trauma center were retrospectively reviewed. This yielded 143 closed fractures, 38 open fractures and 4 closed fractures with an ipsilateral traumatic knee arthrotomy. Patient follow-up records were reviewed for documentation of septic knee via operative notes, wound culture or knee aspirate data, or the administration of antibiotics for suspected septic knee., Results: No evidence of septic knee was found in the 185 fractures examined in the dataset. Utilizing the Wilson confidence interval, the rate of septic knee based on our population was no greater than 2%, with that of the open fracture group alone being 9%., Conclusions: Based on these results and review of the literature, the risk of septic knee in retrograde femoral nailing of both open and closed femoral shaft fractures appears low but potentially not insignificant., Funding: There was no outside source of funding from either industry or other organization for this study.
- Published
- 2012
- Full Text
- View/download PDF
40. Lipid responses in mildly hypertriglyceridemic men and women to consumption of docosahexaenoic acid-enriched eggs.
- Author
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Maki KC, Van Elswyk ME, McCarthy D, Seeley MA, Veith PE, Hess SP, Ingram KA, Halvorson JJ, Calaguas EM, and Davidson MH
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers blood, Blood Proteins drug effects, Blood Proteins metabolism, Body Mass Index, Cholesterol, HDL blood, Cholesterol, HDL drug effects, Cholesterol, LDL blood, Cholesterol, LDL drug effects, Diet Records, Docosahexaenoic Acids blood, Double-Blind Method, Fatty Acids, Omega-3 administration & dosage, Fatty Acids, Omega-3 blood, Female, Humans, Hypertriglyceridemia epidemiology, Illinois epidemiology, Incidence, Male, Middle Aged, Patient Compliance, Severity of Illness Index, Triglycerides blood, Docosahexaenoic Acids administration & dosage, Eggs, Food, Fortified, Hypertriglyceridemia diet therapy, Hypertriglyceridemia metabolism
- Abstract
This randomized, double-blind, controlled clinical trial assessed lipid responses in mildly hyper-triglyceridemic men and women to consumption of docosahexaenoic acid (DHA)-enriched eggs or ordinary chicken eggs. The study included 153 subjects aged 21-80 years, with serum triglyceride concentrations between 140 and 450 mg/dL, inclusive, and serum total cholesterol concentrations < 300 mg/dL. Subjects were randomly assigned to receive either DHA-enriched (147 mg DHA/egg) or ordinary eggs (20 mg DHA/egg), added to their usual diets for six weeks (10 eggs/week). Both treatments significantly lowered triglycerides and increased high-density lipoprotein (HDL) cholesterol levels from baseline; however, these changes were not significantly different between treatments. Low-density lipoprotein (LDL) cholesterol concentrations increased significantly in subjects who consumed DHA-enriched eggs (p = 0.047 vs. control). This increase was significantly higher than that observed with ordinary eggs. However, there was no significant increase in cholesterol carried by small, dense LDL particles, as determined by nuclear magnetic resonance analysis. Results of exploratory analyses suggest favorable effects of the DHA-enriched eggs over ordinary eggs on triglyceride and HDL cholesterol levels in subjects with body mass index > or = 30 kg/m2; the DHA treatment produced a larger reduction in serum triglyceride concentration vs. ordinary eggs (-12.3 vs. 2.1%; p = 0.027), and there was a greater increase for HDL cholesterol in the DHA-enriched vs. ordinary egg group (5.0 vs. 1.1%; p = 0.040).
- Published
- 2003
- Full Text
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41. Lupine influence on soil carbon, nitrogen and microbial activity in developing ecosystems at Mount St. Helens.
- Author
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Halvorson JJ, Smith JL, and Franz EH
- Abstract
Lupine influence on soil C, N, and microbial activity was estimated by comparing root-zone soil (LR) to nonroot-zone soil (NR) collected at Mount St. Helens. Samples were collected from 5 sites forming a gradient of C and N levels as a reflection of different locations and varying volcanic disturbance by the 1980 eruption. In volcanic substrates undergoing primary ecosystem development, C and N levels were low, as would be expected, but higher in LR soil than NR soil. At the least disturbed sites, N was only slightly greater in LR soil whereas significantly less C was observed in LR soil than in surrounding NR soil. Inorganic-N concentrations were small at all sites but comprised a significant proportion of the total amount of soil N in volcanic substrates. In general, LR zone soil contained significantly more NH
inf4 sup+ -N. The addition of glucose increased respiration in soils from all sites with the greatest relative response in volcanic soil from the low end of the C and N gradient. Active soil microbial biomass-C and cumulative respiration were correlated with C and N and were significantly greater in LR soil than in NR soil for all sites. These results are consistent with some expected trends in ecosystem development and demonstrate the significance of resource dynamics and lupines in determining patterns of ecosystem response to disturbance at Mount St. Helens. They also suggest that processes leading to soil heterogeneity can be related to either development or to degradation depending on the context of the specific ecosystem or resource under consideration.- Published
- 1991
- Full Text
- View/download PDF
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