Experimental Ecosystem Eutrophication Causes Offsetting Effects on Emissions of CO2, CH4, and N2O from Agricultural Reservoirs.

Despite decades of research and management efforts, eutrophication remains a persistent threat to inland waters. As nutrient pollution intensifies in the coming decades, the implications for aquatic greenhouse gas (GHG) emissions are poorly defined, particularly the responses of individual GHGs: carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). The biogeochemical controls of each gas can differ, making it difficult to predict the overall effect of nutrient pollution on the net radiative forcing of aquatic ecosystems. Here, we induced eutrophication of small nitrogen (N)-limited agricultural reservoirs and measured changes in diffusive GHG emissions within a before-after-control-impact (BACI) study design during June to September 2021. Each gas exhibited a unique response to 300% increases in primary production, with a shift from an overall CO2 source to a sink, a modest increase in N2O flux, and, unexpectedly, no significant change in CH4 emissions. The lack of net directional change in CO2-equivalent GHG emissions in fertilized reservoirs during the summer contrasts findings from empirical studies of eutrophic lakes. Our findings illustrate the difficulty in extrapolating among different sized ecosystems and suggest that forecast 2-fold increases in agricultural N fertilization by 2050 may not result in consistently elevated GHG emissions during summer, at least from small reservoirs in continental grassland regions.

2023 Clinical Update in Liver Transplantation.

Liver transplantation continues to provide life-saving treatment for patients with end-stage liver disease. Advances in the field of transplant anesthesia continue to support the care of more complex patients. The use of extracorporeal membrane oxygenation has been described in critical care settings and cardiac surgery but may be a valuable option for specific conditions for patients undergoing liver transplantation. Changes to the allocation process for liver grafts now focus on acuity circles to reduce regional disparities. As the number of life-saving transplant surgeries increases, so does the need for specialty knowledge in the anesthetic considerations of these procedures. The specialty of transplant anesthesia continues to grow and develop to meet the demands of complex patients and the increased number of transplants performed. Liver transplantation can be a resource-demanding procedure, and predicting the need for massive transfusion can aid in planning and preparing for significant blood loss.

Editorial Commentary: Utility of Patient-Reported Outcome Threshold Scores to Estimate Patient Satisfaction: 'Let's Ask the Patient!'

The reporting and analysis of patient-reported outcome measures have come a long way. Since the concept of the minimally clinically important difference was first introduced in 1989, threshold scores have grown to include substantial clinical benefit and patient acceptable symptomatic state (PASS). The initial motivation for developing these thresholds was rooted in separating clinical significance from statistical. These thresholds provide insight into the relationship between scores on patient-reported outcome measures (PROM) and patient-reported improvement and satisfaction. It follows that in order to evaluate PROM scores, the best method for deriving the threshold typically uses an anchor-based methodology, i.e., "ask the patient." Specifically, patients are asked how much change they've experienced and whether they consider their current state to be satisfactory. The responses to these questions are compared with the scores on PROMs to find outcome thresholds that best separate patients who reported no improvement from those who reported minimal improvement, substantial improvement, and satisfaction with their current state of health (PASS). The PASS is of particular importance as it speaks to what arguably matters most to patients-a satisfactory state of health. Finally, viewing the PASS from the perspective of variation from study to study rather than as a uniform classifier is needed to make use of the growing number of papers reporting these thresholds. Examining differences in PASS values across papers can provide insight into how well PROM scores reflect patient satisfaction in different settings.

No Difference in Limb Alignment Between Kinematic and Mechanical Alignment Robotic-Assisted Total Knee Arthroplasty.

BACKGROUND: Individualized alignment techniques have gained major interest in an effort to increase satisfaction among total knee arthroplasty patients. This study aimed to compare postoperative alignment between kinematic alignment (KA) and mechanical alignment (MA) and assess whether KA significantly deviates from the principle of aligning the limb as close to neutral alignment as possible. METHODS: There were 234 patients who underwent robotic-assisted total knee arthroplasty using an unrestricted KA and a strict MA technique (KA: 145, MA: 89). The lateral distal femoral angle, medial proximal tibia angle, and the resultant arithmetic hip-knee-ankle angle (aHKA) were measured. The aHKA < 0 indicated varus alignment, while the aHKA > 0 indicated valgus knee alignment. The primary outcome was the frequency of cases that resulted in an aHKA of ± 4° of neutral (0°), as assessed on full-leg standing radiographs obtained at 6 weeks postoperatively. The secondary outcome was the change in coronal plane alignment of the knee classification type from preoperative to postoperative between the MA and KA groups. RESULTS: The mean preoperative aHKA was similar between the 2 groups (P = .19). The KA group had a mean postoperative aHKA of -1.4 ± 2.4°, while the MA group had a mean postoperative aHKA of -0.5 ± 2.1°. No significant difference in limb alignment was identified between KA and MA cases that resulted in hip-knee-ankle angle of ± 4° being neutral (91.7 versus 96.6%, P = .14). There were 97.2% of cases in the KA group that fell within the ± 5° range. The MA group was associated with a significantly higher rate of coronal plane alignment of the knee classification type change from preoperatively to postoperatively (P < .001). CONCLUSIONS: Kinematic alignment achieved similar postoperative aHKA compared to MA, and thus did not significantly deviate from the principle of aligning the limb as close to neutral alignment as possible. Surgeons should feel comfortable starting to introduce individualized alignment techniques. Without being restricted by boundaries, postoperative alignment will be within 5 degrees of neutral 97% of the time.

Decreased Instability in High-Risk (Hip-Spine 2B) Patients After Modifications of Surgical Planning and Technique.

BACKGROUND: Patients undergoing primary total hip arthroplasty (THA) who have spinal deformity and a stiff spine are the highest-risk group for instability. Despite the increasing use of dual-mobility cups and large femoral heads, dislocation remains a major complication after THA. Preoperative planning becomes a critical aspect of ensuring precise component positioning within a safe zone. The purpose of this study was to investigate dislocation rates over a 9-year period. METHODS: A retrospective review of 4,731 THAs performed by 3 orthopaedic surgeons between January 2014 and March 2023 was performed. Spinopelvic measurements were conducted to determine the hip-spine classification group for each patient. Only patients classified as 2B (pelvic incidence-lumbar lordosis > 10° and Δsacral slope < 10°) were eligible. Both absolute and relative dislocation frequencies were then analyzed using time-series analysis techniques and Fisher's exact tests. RESULTS: A total of 281 hip-spine 2B patients undergoing primary THA were eligible for analysis (57% women; mean age, range: 66 years, 23 to 87; mean body mass index, range: 28, 16 to 45). The overall dislocation rate was 4.3%. Use of femoral head sizes ≥ 40 mm increased from 4% in 2014 to 2019 to 37% in 2020 to 2023 (P < .001), while the use of dual-mobility cups decreased from 100% in 2014 to 2019 to 37% in 2020 to 2023 (P < .001). Acetabular component planning was changed from the supine plane to the standing plane in February 2020. Those changes in surgical practice were notably correlated with a significant decrease in dislocation rates from 6.8% in 2014 to 2019 to 1.5% in 2020 to 2023 (P = .03). CONCLUSIONS: Our study demonstrates that the introduction of advanced preoperative THA planning to the standing plane, coupled with precise intraoperative technology for implant placement, can significantly reduce the risk of instability in high-risk THA patients. Notably, we observed a significant decrease in dislocation rates, which aligned with the shift in surgical practice. LEVEL OF EVIDENCE: IV.

Is Tibial Bone Mineral Density Related to Sex, Age, Preoperative Alignment, or Fixation Method in Primary Total Knee Arthroplasty?

BACKGROUND: Cementless total knee arthroplasty (TKA) has regained interest for its potential for long-term biologic fixation. The density of the bone is related to its ability to resist static and cyclic loading and can affect long-term implant fixation; however, little is known about the density distribution of periarticular bone in TKA patients. Thus, we sought to characterize the bone mineral density (BMD) of the proximal tibia in TKA patients. METHODS: We included 42 women and 50 men (mean age 63 years, range: 50 to 87; mean body mass index 31.6, range: 20.5 to 49.1) who underwent robotic-assisted TKA and had preoperative computed tomography scans with a BMD calibration phantom. Using the robotic surgical plan, we computed the BMD distribution at 1 mm-spaced cross-sections parallel to the tibial cut from 2 mm above the cut to 10 mm below. The BMD was analyzed with respect to patient sex, age, preoperative alignment, and type of fixation. RESULTS: The BMD decreased from proximal to distal. The greatest changes occurred within ± 2 mm of the tibial cut. Age did not affect BMD for men; however, women between 60 and 70 years had higher BMD than women ≥ 70 years for the total cut (P = .03) and the medial half of the cut (P = .03). Cemented implants were used in 1 86-year-old man and 18 women (seven < 60 years, seven 60 to 70 years, and four ≥ 70 year old). We found only BMD differences between cemented or cementless fixation for women < 60 years. CONCLUSIONS: To our knowledge, this is the first study to characterize the preoperative BMD distribution in TKA patients relative to the intraoperative tibial cut. Our results indicate that while sex and age may be useful surrogates of BMD, the clinically relevant thresholds for cementless knees remain unclear, offering an area for future studies.

The Inflamma-type: a patient phenotype characterized by a dysregulated inflammatory response after lower extremity articular fracture.

Synovial fluid was collected from 113 patients who had suffered tibial plateau (n = 48), tibial plafond (n = 29), or rotational ankle fractures (n = 36). Concentrations of IL-1ß, IL-1RA, IL-6, IL-8, IL-10, and MMP-1, -3, and -13 were quantified using multiplex assays. A cluster analysis of synovial fluid biomarker concentrations was performed. Patient demographics, fracture type, Injury Severity Score (ISS), Charlson Comorbidity Index (CCI), and biomarker concentrations were compared between clusters. A subset of patients demonstrated a dysregulated inflammatory response after articular fracture including elevated pro-inflammatory cytokines and degradative enzymes previously linked to the development of post-traumatic osteoarthritis.

Periostin regulation and cartilage degradation early after anterior cruciate ligament reconstruction.

OBJECTIVE AND DESIGN: The purpose of this study was to explore pathological processes during the first 4 weeks after anterior cruciate ligament reconstruction (ACLR). SUBJECTS: Sixteen ACL-injured patients (8 females/8 males, mean age = 19.1, mean BMI = 28.6). METHODS: Arthrocentesis was performed 1 and 4 weeks after ACLR. Proteins in the synovial fluid were identified using nanoLC-ESI-MS/MS. Differentially up- or down-regulated proteins were identified and quantified, and a pathway analysis was performed. All identified proteins were mapped into a protein-protein interaction (PPI) network, and networks of PPIs with a combined score > 0.9 were then visualized. RESULTS: Seven pathways were upregulated after ACLR: PI3K-AKT signaling pathway, extracellular matrix (ECM)-receptor interaction, focal adhesion, protein digestion and absorption, ameobiasis, and platelet activation. Network analyses identified 8 proteins that were differentially upregulated with strong PPI interactions (periostin and 7 collagen-related proteins). Increases in periostin moderately correlated with increases in a synovial fluid biomarker of type II cartilage degradation (ρ = 0.51, p = 0.06). CONCLUSION: Pro-inflammatory pathways and periostin were upregulated after ACLR. Periostin demonstrated strong network connections with markers of collagen breakdown, and future work is needed to determine whether periostin may offer a biomarker of early cartilage degradation after ACLR and/or play an active role in early post-traumatic osteoarthritis (PTOA) progression.

Patients With Depression and/or Anxiety Having Arthroscopic Rotator Cuff Repair Show Decreased Number of Prescriptions and Number of Psychotherapy Sessions in the Year After Surgery.

PURPOSE: To determine whether the utilization of psychological treatments changes after arthroscopic rotator cuff repair (RCR) for patients with preoperative depression and/or anxiety. METHODS: The Truven Healthcare Marketscan database was used to identify patients who underwent arthroscopic RCR between January 2009 and December 2016. We included all patients with diagnosis codes associated with either depression or anxiety before RCR. Patients were excluded if they did not have complete insurance coverage for 1 year before or after surgery, or if they had arthroscopic RCR in the year before the index surgical procedure. We compared the proportion of patients with preoperative depression or anxiety who filled a prescription and had psychotherapy procedural codes in the year before and the year after arthroscopic RCR. RESULTS: A total of 170,406 patients who underwent RCR were identified, of which depression and/or anxiety was found in 46,737 patients (43.7% male). Of the 46,737 patients, 19.6% filled a prescription for a depression/anxiety medication at least once in the year before surgery. Of this subset of patients, 41.5% did not fill a prescription for depression or anxiety medication after surgery, whereas 32.6% continued medication use but demonstrated a median 30-day reduction in the number of days' worth of medication. Similarly, 13.1% of patients were attending psychotherapy sessions preoperatively, but 76.6% of those patients either stopped or reduced the amount of psychotherapy sessions in the year following RCR. CONCLUSIONS: The number of prescriptions and psychotherapy sessions decreased in the year after RCR for patients with preoperative diagnoses of depression and/or anxiety. LEVEL OF EVIDENCE: Level IV, case series.

Psychosocial factors play a greater role in preoperative symptoms for patients with atraumatic shoulder instability: data from the MOON-Shoulder Instability group.

BACKGROUND: Previous studies have demonstrated that psychosocial factors and comorbid depression are associated with worse preoperative baseline measures, clinical outcomes, and recovery in patients undergoing shoulder surgery. It is unknown whether this potential link would differ between those with traumatic vs. atraumatic shoulder instability, as symptoms may persist longer in atraumatic instability prior to surgical intervention. The purpose of this study was to determine if psychosocial factors and/or comorbid depression more heavily influence preoperative symptoms for patients with traumatic vs. atraumatic shoulder instability. METHODS: Prospective baseline data from 1552 patients in the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort were analyzed based on mechanism of injury while controlling for age, sex, and direction of instability. Multivariable linear regressions were performed to determine whether psychological factors (RAND 36 Mental Component Score [MCS], depression diagnosis, Personality Assessment Screener-22) were predictive of preoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) and Western Ontario Shoulder Instability Index (WOSI) scores in the atraumatic group. The same model was repeated for the traumatic instability group, and the model fit was compared between groups, with P < .05 considered statistically significant. RESULTS: Female sex and lower MCS were significantly associated with worse preoperative ASES and WOSI scores for the group with atraumatic instability (ASES R2 = 0.15, P < .001; WOSI R2 = 0.17, P < .001). The same model performed significantly worse (P < .05) for both ASES and WOSI scores in the group with traumatic instability (ASES R2 = 0.07, WOSI R2 = 0.08). CONCLUSIONS: Worse preoperative psychosocial factors were found to be more strongly associated with shoulder-related pain and function for patients with atraumatic instability. Across multiple orthopedic conditions, depression and emotional well-being have been associated with worse preoperative symptoms and inferior postoperative patient-reported outcomes. Despite the stronger and significant association in atraumatic patients, worse psychosocial factors did not have as large an impact as has been seen in other, more chronic conditions such as osteoarthritis or rotator cuff tears. In addition to medically optimizing patients prior to surgery, the current findings identify a subset of shoulder instability patients that may benefit from a behavioral health intervention either prior to surgery or early in the postoperative period to potentially improve postoperative outcomes.

Geographic Variation in Knee Phenotypes Based on the Coronal Plane Alignment of the Knee Classification: A Systematic Review.

BACKGROUND: The extent of geographic variation in knee phenotypes remains unclear. The Coronal Plane Alignment of the Knee (CPAK) Classification proposes 9 coronal plane phenotypes based on constitutional limb alignment and joint line obliquity. This systematic review aims to examine differences in the distributions of CPAK types across geographic regions. METHODS: A systematic review of the literature was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting distributions of knee phenotypes according to the CPAK classification for healthy and/or arthritic knees were included. RESULTS: There were 7 studies included, accounting for 5,964 knees in 3,917 subjects. Among healthy knees (n = 1,214), CPAK type II was the most common type in Belgium (39.2%), Taiwan (39.3%), and India (25.6%). Among arthritic knees (n = 2,804), CPAK type I was the most common in France (33.4%), India (58.8%), and Japan (53.8%), whereas CPAK type II was the most common in Australia (32.8%). The proportion of CPAK type I and II knees varied significantly across geographic regions among healthy (P < .01) and arthritic knees (P < .01). CONCLUSION: Significant variation in CPAK distributions exists between countries. Further work is needed to delineate racial and sexual differences in CPAK types, which were not explored in this article. A better understanding of population-level variability in knee phenotypes may enable orthopaedic surgeons to offer a more personalized approach to knee arthroplasty.

Current Concepts in Alignment in Total Knee Arthroplasty.

BACKGROUND: In an effort to increase satisfaction among total knee arthroplasty (TKA) patients, emphasis has been placed on implant positioning and limb alignment. Traditionally, the aim for TKA has been to achieve a neutral mechanical alignment (MA) to maximize implant longevity. However, with the recent spike in interest in individualized alignment techniques and with the advent of new technologies, surgeons are slowly evolving away from classical MA. METHODS: This review elucidates the differences in alignment techniques for TKA, describes the concept of knee phenotypes, summarizes comparative studies between MA and individualized alignment, and provides a simple way to incorporate the latter into surgeons' practice. RESULTS: In order to manage patients by applying these strategies in day-to-day practice, a basic understanding of the aforementioned concepts is essential. Transition to an individualized alignment technique should be done gradually with caution in a stepwise approach. CONCLUSION: Alignment and implant positioning are now at the heart of the debate and surgeons are investigating a more personalized approach to TKA.

2021 Clinical Update in Liver Transplantation.

In 2021, the United States performed 9,236 liver transplantations, an increase of 3.7% from 2020. As the specialty of transplant anesthesiologist continues to grow, so does the body of evidence-based research to improve patient care. New technology in organ preservation offers the possibility of preserving marginal organs for transplant or improving the graft for transplantation. The sequalae of end-stage liver disease have wide-ranging consequences that affect neurologic outcomes of patients both during and after transplantation that anesthesiologists should monitor. Obesity presents several challenges for anesthesiologists. As an increasing number of patients with nonalcoholic steatohepatitis are listed for transplant, managing their multiple comorbidities can be challenging. Finally, the rebalanced hemostasis of end-stage liver disease can cause both bleeding and thrombus. Often, bleeding risks predominate as a concern, but anesthesiologists should be aware of risks of intracardiac thrombus and review therapeutic options for prevention and treatment.

2020 Clinical Update in Liver Transplantation.

The gold standard treatment of end-stage liver disease continues to be liver transplantation (LT). The challenges of LT require skilled anesthesiologists to anticipate physiologic changes associated with end-stage liver disease and surgical considerations that affect multiple organ systems. While on the waiting list, patients may be placed on new anticoagulation medications that can confound already complex coagulopathy in LT patients. Pain management often is an afterthought for such a complex procedure, but appropriate medications can help control pain while limiting opioid medications. Surgical stress and medications for immunosuppression can affect perioperative glucose management in ways that have implications for patient and graft survival. The coronavirus disease 2019 pandemic in 2020 provided a new challenge for anesthesiologists. The uncertainty of the novel respiratory virus challenged providers beyond just LT patients.

Patient-reported outcome scores following patellar instability surgery-high prevalence does not equal high responsiveness: a systematic review.

PURPOSE: The purpose of this study was to determine the utilization and responsiveness of common patient-reported outcomes (PROs) in patients undergoing surgery for patellar instability. METHODS: Using PRISMA guidelines, a systematic review of studies reporting outcomes following surgical intervention for patellar instability was conducted using Pubmed, Cochrane, OVID Medline, and Google Scholar. Subgroup analysis of articles reporting at least two PROs with baseline and follow-up data were used to evaluate responsiveness of instruments using relative efficiency and effect size. RESULTS: From the search, 2,848 unique articles were found, of which 178 were included in final analysis (7,122 patients, mean age 22.6, 63.6% female). The most commonly used PRO was the Kujala score (79.2%), followed by the Lysholm (34.8%), and Tegner (30.9%). Seventy-nine articles were eligible for subgroup analysis. The Kujala had a higher relative efficiency than ten of the 14 instruments to which it was compared but had lower relative efficiency compared to the IKDC and Lysholm scores. The Banff Patella Instability Instrument (BPII) and the Norwich score, condition-specific tools, were unable to be fully assessed due to rarity of use and lack of comparisons. CONCLUSION: The hypothesis that the Kujala score is the most commonly used PRO for patellar instability, although other instruments offer greater efficiency was supported by our results. The IKDC and Lysholm scores had similar effect sizes but higher relative efficiencies than the Kujala, thus suggesting better responsiveness. This analysis adds useful information for surgeons on the effectiveness of the most common PRO's for evaluating patellofemoral instability outcomes. LEVEL OF EVIDENCE: Level III.

Self-Reported Health of Severely Obese US Adults With Osteoarthritis.

BACKGROUND: Severe obesity is associated with complications following arthroplasty, leading surgeons to increasingly counsel patients regarding weight loss. For patients seeking arthroplasty, learning that severe obesity may be a relative contraindication to surgery can create a challenging clinical interaction. We sought to describe the self-reported health of United States (US) adults who had severe obesity and osteoarthritis (OA) to better understand patient perspectives. METHODS: The National Health and Nutrition Examination Survey, a nationally representative sample of the US population, was used to identify adult participants who had a body mass index (BMI) over 35 and an OA diagnosis. In total, 889 participants representing a US population of 9,604,722 were included. Self-reported health was dichotomized as poor to fair versus good to excellent. Analyses were weighted to produce national estimates. Associations between obesity severity and patient characteristics with self-reported health were assessed. RESULTS: Of US adults with a BMI over 35 and OA diagnosis, 64% rated their health as good or better. For adults who had a BMI over 45, 55% still reported their health as good or better. The strongest predictors of self-reported health were measures of physical functioning. Only 37% of participants who had much difficulty walking a quarter mile rated their health as good or better compared to 86% without difficulty (P < .001). CONCLUSION: Approximately two-thirds of patients who have severe obesity and OA do not perceive their health as compromised and consider decreased physical function as the primary driver of decreased health. This suggests that counseling about the association between obesity and overall health may improve shared decision making and that patient satisfaction metrics may be difficult to interpret in these clinical situations.

Tetracycline use in treating osteoarthritis: a systematic review.

BACKGROUND AND AIMS: The purpose of the review was to synthesize the current literature regarding tetracyclines in the treatment of osteoarthritis. METHODS: Using multiple databases, a systematic review was performed with customized search terms crafted to identify studies examining doxycycline or minocycline in the treatment of osteoarthritis. Results were classified into basic science mechanistic studies, in vivo animal studies, and human clinical trials. A total of 1446 potentially relevant studies were reviewed, and after exclusion criteria were applied, 23 investigations were included in the final analysis. RESULTS: From 12 basic science mechanistic studies, we report on three main mechanisms by which tetracyclines may exert benefit in osteoarthritis progression: matrix metalloproteinase inhibition, immunomodulation, and nitric oxide synthase inhibition. Seven animal studies showed generally encouraging results. Four articles reported human clinical studies, showing mixed results in the treatment of osteoarthritis, potentially related to the choice of patient population, primary outcomes, and timing of treatment. CONCLUSION: Tetracyclines have the potential to benefit osteoarthritis patients via multiple mechanisms. Further study is warranted to examine the optimal dose and timing of tetracycline treatment in osteoarthritis.

2019 Clinical Update in Liver Transplantation.

Liver transplantation continues be the standard for treatment of end-stage liver disease, and even with recent advances in organ preservation, the anesthetic management continues to require understanding of multiple organ systems beyond the liver. Multiple factors contribute to hemodynamic changes after reperfusion of the liver graft that anesthesiologists should be aware of before unclamping. Concomitant renal dysfunction in end-stage liver disease is not uncommon, and preparation for continuous renal replacement therapy may need to be considered in certain cases. Cardiac evaluation of liver transplantation patients with an emphasis on arrhythmias, including atrial fibrillation, can help prevent both intraoperative and postoperative complications detrimental to the patient and graft. Finally, combined liver and thoracic organ transplantations may be indicated for certain disease processes that affect multiple organs. These cases require an understanding of the surgical technique and acknowledgment that some goals of the procedures may be in direct opposition to each other.

Which Risk Factors Are Associated with Pain and Patient-reported Function in Patients with a Rotator Cuff Tear?

BACKGROUND: Patient-reported measures guide physicians in clinical decision making and therefore it is critical to determine what clinical factors are associated with these scores. Psychological and physical factors are commonly studied separately in patients with rotator cuff tears to determine their influence on outcomes. It is well established that psychological distress and scapular motion change in the presence of a symptomatic rotator cuff tear. However, these factors have not been studied simultaneously in a clinical setting to determine their association with shoulder outcome scores. QUESTION/PURPOSE: After controlling for relevant confounding variables, what physical and psychological factors are associated with better (1) American Shoulder and Elbow Surgeons (ASES) scores for function, (2) ASES pain scores, and (3) total ASES scores? METHODS: Fifty-nine patients with a potential symptomatic rotator cuff tear were recruited and agreed to participate in this cross-sectional study. Of those, 85% (50 of 59) met eligibility criteria for a primary diagnosis of an MRI-confirmed symptomatic partial-thickness or full-thickness rotator cuff tear without a history of shoulder surgery. Demographics, rotator cuff tear size, arm flexion, and clinical scapular motion during active arm flexion were evaluated by experienced examiners using standardized procedures. Patients completed the ASES questionnaire and the Optimal Screening for Prediction of Referral and Outcomes-Yellow Flag assessment form, which measures 11 different pain-related psychological distress symptoms. Three separate stepwise multiple linear regression analyses were performed for ASES pain, function, and total scores, with significance set at p < 0.05. RESULTS: This model found that ASES function scores were associated with four factors: older age, increased arm flexion, increased percentage of scapular external rotation during arm flexion, and increased scores for acceptance of chronic pain (adjusted r2 = 0.67; p = 0.01). Those four factors appear to explain 67% of the observed variance in ASES function scores in patients with rotator cuff tears. Furthermore, increased percentage of scapular external rotation during arm flexion and decreased fear-avoidance beliefs related to physical activity scores (adjusted r2 = 0.36; p < 0.01) were associated with better ASES pain scores. And finally, better ASES total scores were associated with four factors: increased arm flexion, increased percentage of scapular upward rotation, increased scapular external rotation during arm flexion, and decreased fear-avoidance beliefs related to physical activity scores (adjusted r2 = 0.65; p < 0.001). CONCLUSION: Our results favor adopting a comprehensive biopsychological clinical assessment for patients with rotator cuff tears that specifically includes humeral and scapular motion, fear-avoidance behaviors, and pain coping behaviors along with demographics. These particular physical and psychological variables were found to be associated with the ASES and, therefore, should be clinically examined simultaneously and targeted as part of a tailored treatment plan. LEVEL OF EVIDENCE: Level II, prognostic study.

Early Antibiotic Administration Is Associated with a Reduced Infection Risk When Combined with Primary Wound Closure in Patients with Open Tibia Fractures.

BACKGROUND: Early administration of antibiotics and wound coverage have been shown to decrease the deep infection risk in all patients with Type 3 open tibia fractures. However, it is unknown whether early antibiotic administration decreases infection risk in patients with Types 1, 2, and 3A open tibia fractures treated with primary wound closure. QUESTIONS/PURPOSES: (1) Does decreased time to administration of the first dose of antibiotics decrease the deep infection risk in all open tibia fractures with primary wound closure? (2) What patient demographic factors are associated with an increased deep infection risk in Types 1, 2, and 3A open tibia fractures with primary wound closure? METHODS: We identified 361 open tibia fractures over a 5-year period at a Level I regional trauma center that receives direct admissions and transfers from other hospitals which produces large variation in the timing of antibiotic administration. Patients were excluded if they were younger than 18 years, had associated plafond or plateau fractures, associated with compartment syndrome, had a delay of more than 24 hours from injury to the operating room, underwent repeat débridement procedures, had incomplete data, and were treated with negative-pressure dressings or other adjunct wound management strategies that would preclude primary closure. Primary closure was at the descretion of the treating surgeon. We included patients with a minimum follow-up of 6 weeks with assessment at 6 months and 12 months. One hundred forty-three patients with were included in the analysis. Our primary endpoint was deep infection as defined by the CDC criteria. We obtained chronological data, including the time to the first dose of antibiotics and time to surgical débridement from ambulance run sheets, transferring hospital records, and the electronic medical record to answer our first question. We considered demographics, American Society of Anesthesiologists classification, mechanism of injury, smoking status, presence of diabetes, and Injury Severity Score in our analysis of other factors. These were compared using one-way ANOVA, chi-square, or Fisher's exact tests. Binary regression was used to to ascertain whether any factors were associated with postoperative infection. Receiver operator characteristic curves were used to identify threshold values. RESULTS: Increased time to first administration of antibiotics was associated with an increased infection risk in patients who were treated with primary wound closure; the greatest inflection point on that analysis occurred at 150 minutes, when the increased infection risk was greatest (20% [8 of 41] versus 4% [3 of 86]; odds ratio 5.6 [95% CI 1.4 to 22.2]; p = 0.01). After controlling for potential confounding variables like age, diabetes and smoking status, none of the variables we evaluated were associated with an increased risk of deep infection in Type 1, 2, and 3A open tibia fractures in patients treated with primary wound closure. CONCLUSION: Our findings suggest that in open tibia fractures, which receive timely antibiotic administration, primary wound closure is associated with a decreased infection risk. We recognize that more definitive studies need to be performed to confirm these findings and confirm feasibility of early antibiotic administration, especially in the pre-hospital context. LEVEL OF EVIDENCE: Level III, therapeutic study.