Citations

Objective: To determine the disease-free survival (DFS) and recurrence after the treatment of patients with rectal cancer with open (OPEN) or laparoscopic (LAP) resection. Background: This randomized clinical trial (ACOSOG [Alliance] Z6051), performed between 2008 and 2013, compared LAP and OPEN resection of stage II/III rectal cancer, within 12 cm of the anal verge (T1-3, N0-2, M0) in patients who received neoadjuvant chemoradiotherapy. The rectum and mesorectum were resected using open instruments for rectal dissection (included hybrid hand-assisted laparoscopic) or with laparoscopic instruments under pneumoperitoneum. The 2-year DFS and recurrence were secondary endpoints of Z6051. Methods: The DFS and recurrence were not powered, and are being assessed for superiority. Recurrence was determined at 3, 6, 9, 12, and every 6 months thereafter, using carcinoembryonic antigen, physical examination, computed tomography, and colonoscopy. In all, 486 patients were randomized to LAP (243) or OPEN (243), with 462 eligible for analysis (LAP = 240 and OPEN = 222). Median follow-up is 47.9 months. Results: The 2-year DFS was LAP 79.5% (95% confidence interval [CI] 74.4–84.9) and OPEN 83.2% (95% CI 78.3–88.3). Local and regional recurrence was 4.6% LAP and 4.5% OPEN. Distant recurrence was 14.6% LAP and 16.7% OPEN. Disease-free survival was impacted by unsuccessful resection (hazard ratio [HR] 1.87, 95% CI 1.21–2.91): composite of incomplete specimen (HR 1.65, 95% CI 0.85–3.18); positive circumferential resection margins (HR 2.31, 95% CI 1.40–3.79); positive distal margin (HR 2.53, 95% CI 1.30–3.77). Conclusion: Laparoscopic assisted resection of rectal cancer was not found to be significantly different to OPEN resection of rectal cancer based on the outcomes of DFS and recurrence.

Background: The efficacy of a neuromuscular training (NMT) program to ameliorate known hip biomechanical risk factors for athletes with anterior cruciate ligament reconstruction (ACLR) is currently unknown. Purpose/Hypothesis: The purpose was to quantify the effects of an NMT program on hip biomechanics among athletes with ACLR and to compare posttraining hip biomechanics with a control group. The hypotheses were that known hip biomechanical risk factors of anterior cruciate ligament (ACL) injury would be significantly reduced among athletes with ACLR after the NMT program and that posttraining hip biomechanics between the ACLR and control cohorts would not differ. Study Design: Controlled laboratory study. Methods: Twenty-eight athletes (n = 18, ACLR; n = 10, uninjured) completed a 12-session NMT program. Biomechanical evaluation of a jump-landing task was done before and after completion of the program. Repeated measures analysis of variance was performed to understand the effect of NMT within the ACLR cohort. Two-way analysis of variance was used to compare both groups. Post hoc testing was done for significant interactions. Hip biomechanical variables at initial contact are reported. Results: The athletes with ACLR who completed the NMT program had a significant session × limb interaction ( P = .01) for hip external rotation moment and a significant main effect of session for hip flexion angle ( P = .049) and moment ( P < .001). There was a significant change for the involved ( P = .04; 528% increase) and uninvolved ( P = .04; 57% decrease) limbs from pre- to posttraining for hip rotation moment. The ACLR cohort had an increase in hip flexion angle (14% change) and a decrease in hip flexion moment (65% change) from pre- to posttraining. Posttraining comparison for these same hip biomechanical variables of interest revealed no significant interactions ( P > .05) between the ACLR and control cohorts. There was a significant main effect of group ( P = .02) for hip flexion angle, as the ACLR cohort demonstrated greater hip flexion angle than that of the control group. Conclusion: For athletes with ACLR, hip biomechanical measures of ACL injury risk show significant improvements after completion of an NMT program. Clinical Relevance: Athletes with ACLR who are participating in an NMT program may ameliorate known hip biomechanical risk factors for an ACL injury.

Background: Clinical management of sport-related concussion typically involves a symptom checklist, clinical examination of mental status, and neurocognitive testing. However, recent studies have identified unresolved, impaired sensorimotor function after athletes return to sport. A review and meta-analysis of all current literature regarding risk of subsequent musculoskeletal (MSK) injury after concussion has yet to be published in the medical literature. Purpose/Hypothesis: To determine the odds that athletes will sustain MSK injury after concussion. It was hypothesized a priori that concussion would increase the risk for MSK injury. Study Design: Systematic review and meta-analysis. Methods: PubMed and Google Scholar were searched from January 2000 to November 2017. Reference lists of the included studies were manually searched. Two reviewers independently searched the literature for studies published in English that reported MSK injury after athletes returned to play following a concussion. Two independent reviewers completed data extraction using PRISMA guidelines and assessed study quality using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies from the National Institutes of Health. Random effects meta-analyses were used to calculate odds ratio (OR) and incidence rate ratio (IRR) of MSK injury after concussion. The primary study outcome of interest was the number of athletes who sustained MSK injury after concussion. Results: Eight studies met inclusion criteria for meta-analysis. Meta-analysis results indicated that athletes who had a concussion had 2 times greater odds of sustaining a MSK injury than athletes without concussion (OR, 2.11; 95% CI, 1.46-3.06). In addition, athletes with concussion demonstrated a higher incidence of MSK injury after return to sport compared with nonconcussed athletes (IRR, 1.67; 95% CI, 1.42-1.96). Further analysis showed that both male and female athletes with concussion were at an increased risk of MSK injury compared with their respective same-sex, nonconcussed controls (OR > 1.56, P < .01). Conclusion: Based on the evidence of higher risk of MSK injuries after concussion, standard clinical assessments for athletes with concussion should include not only physical symptoms and cognitive function before return to sport but also neuromuscular risk factors associated with increased risk for MSK injuries.

Abstract The objective of this retrospective analysis was to describe the development and implementation of an anesthesiologist‐led multidisciplinary committee to evaluate high‐risk surgical patients in order to improve surgical appropriateness. The study was conducted in an anesthesia preoperative evaluation clinic at an academic comprehensive cancer center. One hundred sixty‐seven high‐risk surgical patients with cancer‐related diagnoses were evaluated and discussed at a High‐Risk Committee (HRC) meeting to determine surgical appropriateness and optimize perioperative care. The HRC is an anesthesiologist‐led model for multidisciplinary review of high‐risk patients developed at Roswell Park Comprehensive Cancer Center. The group of high‐risk patients in which surgery was not performed had, on average, a greater percentage of hypertension, smoking history, dyspnea, heart failure, chronic obstructive pulmonary disease, diabetes, renal failure, and sleep apnea than the group in whom surgery was performed. Only one of 107 high‐risk patients who had surgery died within the first 30 days after surgery. A smaller percentage of patients died in the group that had surgery versus the group in which surgery was canceled. For all patients discussed by the HRC, the mortality was less than 2% within the first 30 days after the HRC.

The PREVENtion of HeartMate II pump Thrombosis through clinical management (PREVENT) study was a multicenter, prospective investigation to evaluate the rate of pump thrombosis (PT) with adoption of a uniform set of surgical and medical practices for left ventricular assist device implantation. We sought to quantify pump position at baseline and retrospectively define a pump position associated with poor clinical outcomes. Chest x-rays at baseline were prospectively obtained per protocol. Pump pocket depth, inflow cannula (IC) angle relative to the pump, and IC angle relative to the vertical were measured. Pumps falling in the tail-ends of the IC angle and pump pocket depth distributions were categorized as having an extreme pump position within the PREVENT study. Patients with extreme pump position had a significantly higher risk of confirmed and suspected PT, hemolysis, and elevated lactate dehydrogenase. In a multivariable analysis of survival free of confirmed PT, extreme pump position was an independent risk factor (hazard ratio = 3.6; 95% confidence interval = 1.5–8.9; p = 0.006) when adjusting for differences in pump speed and anticoagulation level. Our analysis shows that HeartMate II pump position at implant can significantly impact event-free survival and the incidence of adverse events at 6 months.

Background: Anterior cruciate ligament (ACL) injuries are catastrophic events that affect athletic careers and lead to long-term degenerative knee changes. As injuries are believed to occur within the first 50 milliseconds after initial contact during a rapid deceleration task, impact simulators that rapidly deliver impulse loads to cadaveric specimens have been developed. However, no impactor has reproducibly and reliably created ACL injures in a distribution that mimics clinical observation. Purpose: To better understand ACL injury patterns through a cadaveric investigation that applied in vivo–measured external loads to the knee during simulated landings. Study Design: Controlled laboratory study. Methods: A novel mechanical impact simulator reproduced kinetics from in vivo–recorded drop landing tasks on 45 cadaveric knees. Specimens were exposed to a randomized order of variable knee abduction moment, anterior tibial shear, and internal tibial rotation loads before the introduction of an impulse load at the foot. This process was repeated until a hard or soft tissue injury was induced on the joint. Injuries were assessed by an orthopaedic surgeon, and ligament strain was recorded by implanted strain gauges. Results: The mechanical impact simulator induced ACL injuries in 87% of specimens, with medial collateral ligament (MCL) injuries in 31%. ACL tear locations were 71% femoral side, 21% midsubstance, and 9% tibial side. Peak strain before failure for ACL-injured specimens was 15.3% ± 8.7% for the ACL and 5.1% ± 5.6% for the MCL ( P < .001). Conclusion: The ACL injuries induced by the mechanical impact simulator in the present study have provided clinically relevant in vitro representations of in vivo ACL injury patterns as cited in the literature. Additionally, current ligament strains corroborate the literature to support disproportionate loading of the ACL relative to the MCL during athletic tasks. Clinical Relevance: These findings indicate that the mechanical impact simulator is an appropriate model for examining independent mechanical variables, treatment techniques, and preventive interventions during athletic tasks leading up to and including an ACL injury. Accordingly, this system can be utilized to further parse out contributing factors to an ACL injury as well as assess the shortcomings of ACL reconstruction techniques in a dynamic, simulated environment that is better representative of in vivo injury scenarios.

Abstract BACKGROUND A decrease in diastolic blood pressure (DBP) with exercise is considered normal, but the significance of an increase in DBP has not been validated. Our aim was to determine the relationship of DBP increasing on a stress test regarding comorbidities and mortality. METHODS Our database was reviewed from 1993 to 2010 using the first stress test of a patient. Non-Minnesota residence, baseline cardiovascular (CV) disease, rest DBP &lt;60 or &gt;100 mm Hg, and age &lt;30 or ≥80 were exclusion criteria. DBP response was classified: normal if peak DBP–rest DBP &lt; 0, borderline 0–9, and abnormal ≥10 mm Hg. Mortality was determined from Mayo Clinic records and Minnesota Death Index. Logistic regression was used to determine the relationship of DBP response to the presence of comorbidities. Cox regression was used to determine total and CV mortality risk by DBP response. All analyses were adjusted for age, sex, and resting DBP. RESULTS Twenty thousand seven hundred sixty patients were included (51 ± 11 years, female n = 7,314). Rest/peak averaged DBP 82 ± 8/69 ± 15 mm Hg in normal vs. 79 ± 9/82 ± 9 mm Hg in borderline vs. 76 ± 9/92 ± 11 mm Hg in abnormal DBP response. There were 1,582 deaths (8%) with 557 (3%) CV deaths over 12 ± 5 years of follow-up. In patients with borderline and abnormal DBP response, odds ratios for obesity, hypertension, diabetes, and current smoking were significant, while hazard ratios for total and CV death were not significant compared with patients with normal DBP response. CONCLUSIONS DBP response to exercise is significantly associated with important comorbidities at the time of the stress test but does not add to the prognostic yield of stress test.

Background: Female patients sustain noncontact knee ligament injuries at a greater rate compared with their male counterparts. The cause of these differences in the injury rate and the movements that load the ligaments until failure are still under dispute in the literature. Purpose/Hypotheses: This study was designed to determine differences in anterior cruciate ligament (ACL) and medial collateral ligament (MCL) strains between male and female cadaveric specimens during a simulated athletic task. The primary hypothesis tested was that female limbs would demonstrate significantly greater ACL strain compared with male limbs under similar loading conditions. A secondary hypothesis was that MCL strain would not differ between sexes. Study Design: Controlled laboratory study. Methods: Motion analysis of 67 athletes performing a drop vertical jump was conducted. Kinetic data were used to categorize injury risk according to tertiles, and these values were input into a cadaveric impact simulator to assess ligamentous strain during a simulated landing task. Uniaxial and multiaxial load cells and differential variable reluctance transducer strain sensors were utilized to collect mechanical data for analysis. Conditions of external loads applied to the cadaveric limbs (knee abduction moment, anterior tibial shear, and internal tibial rotation) were varied and randomized. Data were analyzed using 1-way analysis of variance (ANOVA), 2-way repeated-measures ANOVA, and the Fisher exact test. Results: There were no significant differences ( P = .184) in maximum ACL strain between male (13.2% ± 8.1%) and female (16.7% ± 8.3%) specimens. Two-way ANOVA demonstrated that across all controlled external load conditions, female specimens consistently attained at least 3.5% increased maximum ACL strain compared with male specimens ( F 1,100 = 4.188, P = .043); however, when normalized to initial contact, no significant difference was found. There were no significant differences in MCL strain between sexes for similar parameters. Conclusion: When compared with baseline, female specimens exhibited greater values of ACL strain at maximum, initial contact, and after impact (33, 66, and 100 milliseconds, respectively) than male specimens during similar loading conditions, with a maximum strain difference of at least 3.5%. During these same loading conditions, there were no differences in MCL loading between sexes, and only a minimal increase of MCL loading occurred during the impact forces. Our results indicate that female patients are at an increased risk for ACL strain across all similar conditions compared with male patients. Clinical Relevance: These data demonstrate that female specimens, when loaded similarly to male specimens, experience additional strain on the ACL. As the mechanical environment was similar for both sexes with these simulations, the greater ACL strain of female specimens must be attributed to ligament biology, anatomic differences, or muscular stiffness.