Abstract
Neurobiological underpinnings of cortical thickness in the human brain are largely unknown. Here we use cell-type-specific gene markers to evaluate the contribution of 9 neural cell-types in ...explaining inter-regional variations in cortical thickness and age-related cortical thinning in the adolescent brain. Gene-expression data were derived from the Allen Human Brain Atlas (and validated using the BrainSpan Atlas). Values of cortical thickness/thinning were obtained with magnetic resonance imaging in a sample of 987 adolescents. We show that inter-regional profiles in cortical thickness relate to those in the expression of genes marking CA1 pyramidal cells, astrocytes, and microglia; taken together, the 3 cell types explain 70% of regional variation in cortical thickness. We also show that inter-regional profiles in cortical thinning relate to those in the expression of genes marking CA1 and S1 pyramidal cells, astrocytes and microglia. Using Gene Ontology analysis, we demonstrate that the difference in the contribution of CA1 and S1 pyramidal cells may relate to biological processes such as neuronal plasticity and potassium channel activity, respectively. This "virtual histology" approach (scripts provided) can be used to examine neurobiological underpinnings of cortical profiles associated with development, aging, and various disorders.
Background
Since the original description by Letournel in 1961, the ilioinguinal approach has remained the predominant approach for anterior acetabular fixation. However, modifications of the ...original abdominal approach described by Stoppa have made another option available for reduction and fixation of pelvic and acetabular fractures.
Questions/purposes
We evaluated our results in patients with acetabulum fractures with the modified Stoppa approach in terms of (1) hip function as measured by the Merle d’Aubigne hip score; (2) complications; and (3) quality of fracture reduction and percentage of fractures that united.
Methods
Between September 2008 and August 2012, 289 patients with acetabular fractures were treated at our Level I trauma center. Twelve percent (36 of 289) of patients were treated operatively using the modified Stoppa approach. Ninety-seven percent (35 of 36) of our patients had fracture patterns involving displacement of the posterior column. Six (17%) were converted early to a total hip arthroplasty, and 14 (39%) were lost to final followup, leaving 22 of 36 for subjective clinical outcome analysis at a mean of 32 months (range, 9–59 months). Our general indications for this approach during the period in question were fractures of the anterior column and anterior wall, anterior column with posterior hemitransverse fractures, both column fractures, transverse fractures, and T-type fractures. Followup included regularly scheduled office visits with radiographs (AP pelvis, Judet views) that were graded by the treating surgeon and by the authors of this study (MJI, BCT) and patient outcome surveys.
Results
Merle d’Aubigne hip scores were very good in 55% (12 of 22), good in 9% (two of 22), medium in 18% (four of 22), fair in 5% (one of 22), and poor in 14% (three of 22), and 70% (23 of 33) of patients were able to ambulate without any assistive devices. Complications included one superficial infection and three deep infections, two patients with temporary lateral thigh numbness, no obturator nerve palsies, and one inguinal hernia. Three deaths in the cohort were seen in followup as a result of unrelated causes. Radiographic grading of fracture reductions after surgery revealed that 27 (75%) were anatomic, six (17%) were satisfactory, and three (8%) were unsatisfactory. A total of 94% of the fractures united.
Conclusions
In agreement with prior published data, our results show good functional outcomes with minimal complications using the modified Stoppa approach for a variety of acetabular fractures. Our results highlight the difficulty but feasibility in treating posterior column displacement through an anterior approach. Consideration for dual approaches with posterior column involvement may be warranted to optimize fracture reduction and functional outcomes.
Level of Evidence
Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
Operative treatment of displaced patella fractures with tension band fixation remains the gold standard, but is associated with a significant rate of complications and symptomatic implants. Despite ...the evolution of tension band fixation to include cannulated screws, surprisingly little other development has been made to improve overall patient outcomes. In this article, we present the techniques and outcomes of patella plating for displaced patella fractures and patella nonunions.
Abstract Objective In recent years, concerns have been raised about the learning opportunities available to cardiac surgical trainees. This meta-analysis was conducted to assess the impact of trainee ...operator status on clinical outcomes after coronary artery bypass graft (CABG) surgery. Methods Medline, EMBASE, and the Cochrane Library were systematically searched for studies that reported CABG outcomes according to the training status of the primary operator (consultant vs trainee). Data were independently extracted by 2 investigators; a meta-analysis was conducted according to predefined clinical endpoints. Results Sixteen observational studies (n = 52,966) met criteria for inclusion, with 8 studies (n = 36,479) reporting propensity-adjusted analyses. Trainee cases were associated with increased aortic crossclamp duration (mean difference: 4.80; 95% confidence interval CI, 0.76-8.83) and cardiopulmonary bypass duration (mean difference: 4.24; 95% CI, 0.00-8.47). Perioperative mortality was similar for CABG performed primarily by trainees versus consultants (odds ratio 0.98; 95% CI, 0.81-1.18). No significant difference was found in the incidence of perioperative stroke, myocardial infarction, acute renal failure, reoperation for bleeding, or wound infection. Trainee operator status was not associated with increased midterm mortality (hazard ratio 1.00; 95% CI, 0.90-1.11). In subgroup analysis that included 5 studies and 8025 patients, off-pump CABG trainee cases were not associated with increased perioperative mortality or morbidity. Conclusions With appropriate supervision, conventional CABG can be performed by trainee surgeons without an adverse impact on perioperative outcomes or midterm survival. Data regarding off-pump CABG are limited, and further research is warranted to ascertain the impact of trainee operator status on long-term outcomes after off-pump CABG.
Operative fixation of rib fracture nonunions DeGenova, Daniel T.; Miller, Klay B.; McClure, Tanner T. ...
Archives of orthopaedic and trauma surgery,
06/2023, Letnik:
143, Številka:
6
Journal Article
Recenzirano
Introduction
Rib fractures are common injuries in trauma patients that often heal without intervention. Infrequently, symptomatic rib fracture nonunions are a complication after rib fractures. There ...is a paucity of literature on the surgical treatment of rib fracture nonunion. The purpose of this study was to describe the efficacy of rib fracture nonunion operative fixation with particular focus on surgical technique, healing rates, and complications.
Materials and methods
Patients aged ≥ 18 years with symptomatic rib fracture nonunions treated with open reduction and internal fixation (ORIF) with locking plates at a single urban level 1 trauma center were retrospectively reviewed. Pertinent demographic, clinical, radiographic, and surgical data were collected and analyzed.
Results
A total of 18 patients met inclusion criteria. The mean time from injury to undergoing ORIF for rib fracture nonunion was just under a year and the number of ribs plated was 2.95 ± 1.16 (1–5 ribs) with bone grafting used in six cases. All patients (100%) showed evidence of healing at an average of 2.65 ± 1.50 months (2–8 months). All patients reported a decrease in pain. No narcotic pain medication was used at an average of 3.88 ± 3.76 weeks (0–10 weeks) post-operatively. Intraoperative and postoperative complications were found in 4 (22.2%) patients.
Conclusion
This study concluded that operative fixation of symptomatic rib fracture nonunion demonstrated favorable outcomes with reduction in preoperative pain levels, decreased use of narcotic pain medication, minimal complications, and a high rate of fracture union. This described method provides symptomatic relief, reduction in pain, and promotes bony healing of the fracture nonunion without development of major complications. We suggest that operative fixation should be considered as the primary method of treatment of symptomatic rib nonunions.
Cannabis use during adolescence is known to increase the risk for schizophrenia in men. Sex differences in the dynamics of brain maturation during adolescence may be of particular importance with ...regard to vulnerability of the male brain to cannabis exposure.
To evaluate whether the association between cannabis use and cortical maturation in adolescents is moderated by a polygenic risk score for schizophrenia.
Observation of 3 population-based samples included initial analysis in 1024 adolescents of both sexes from the Canadian Saguenay Youth Study (SYS) and follow-up in 426 adolescents of both sexes from the IMAGEN Study from 8 European cities and 504 male youth from the Avon Longitudinal Study of Parents and Children (ALSPAC) based in England. A total of 1577 participants (aged 12-21 years; 899 57.0% male) had (1) information about cannabis use; (2) imaging studies of the brain; and (3) a polygenic risk score for schizophrenia across 108 genetic loci identified by the Psychiatric Genomics Consortium. Data analysis was performed from March 1 through December 31, 2014.
Cortical thickness derived from T1-weighted magnetic resonance images. Linear regression tests were used to assess the relationships between cannabis use, cortical thickness, and risk score.
Across the 3 samples of 1574 participants, a negative association was observed between cannabis use in early adolescence and cortical thickness in male participants with a high polygenic risk score. This observation was not the case for low-risk male participants or for the low- or high-risk female participants. Thus, in SYS male participants, cannabis use interacted with risk score vis-à-vis cortical thickness (P = .009); higher scores were associated with lower thickness only in males who used cannabis. Similarly, in the IMAGEN male participants, cannabis use interacted with increased risk score vis-à-vis a change in decreasing cortical thickness from 14.5 to 18.5 years of age (t137 = -2.36; P = .02). Finally, in the ALSPAC high-risk group of male participants, those who used cannabis most frequently (≥61 occasions) had lower cortical thickness than those who never used cannabis (difference in cortical thickness, 0.07 95% CI, 0.01-0.12; P = .02) and those with light use (<5 occasions) (difference in cortical thickness, 0.11 95% CI, 0.03-0.18; P = .004).
Cannabis use in early adolescence moderates the association between the genetic risk for schizophrenia and cortical maturation among male individuals. This finding implicates processes underlying cortical maturation in mediating the link between cannabis use and liability to schizophrenia.
Multiple surgeries are often required to manage segmental bone loss because of the complex mechanics and biology involved in reconstruction. These procedures can lead to prolonged recovery times, ...poor patient outcomes, and even delayed amputation. A two-stage technique uses induced biologic membranes with delayed placement of bone graft to manage this clinical challenge. In the first stage, a polymethyl methacrylate spacer is placed in the defect to produce a bioactive membrane, which appears to mature biochemically and physically 4 to 8 weeks after spacer placement. In the second, cancellous autograft is placed within this membrane and, via elution of several growth factors, the membrane appears to prevent graft resorption and promote revascularization and consolidation of new bone. Excellent clinical results have been reported, with successful reconstruction of segmental bone defects >20 cm.
Abstract Introduction Simultaneous ipsilateral clavicle and acromioclavicular (AC) joint injury have been infrequently reported in the literature at this time. The purpose of this study was to assess ...incidence as well as assess risk factors for this dual injury pattern. Methods We performed a retrospective review of a prospectively collected database (Level III evidence), evaluating 383 adult patients without previous shoulder girdle injury or trauma with a minimum 1-year follow-up who sustained a displaced diaphyseal clavicle fracture. All patients in the study underwent either nonoperative management or surgical reduction and stabilization of a diaphyseal clavicle fracture with a plate and screw construct. Study subjects were followed with serial radiographs. Clavicle and shoulder radiographs, as well as chest radiographs and contralateral films in questionable cases, were used to assess for acromioclavicular joint injury in both operative and nonoperative groups. Additional data was collected on concurrent injuries, patient demographics, fracture characteristics, fixation techniques, surgical/post-operative data, and operative or nonoperative treatment. Results We found that 13/183 (7.1%) of patients undergoing fixation of a diaphyseal clavicle fracture had an ipsilateral AC joint injury, while 13/200 (6.5%) of patients undergoing conservative management had an ipsilateral AC joint injury. Critical analysis of the data revealed that presence of ipsilateral scapular body fractures, and a likely incidental association with superior plating fixation, were associated with an increased rate of this injury pattern. Conclusions Ipsilateral clavicle fracture and AC joint injury is much more common than traditionally believed, with an incidence of 6.8% overall. It is unknown how the presence of an associated AC injury influences outcome, as AC injury was not universally symptomatic.
Recent reported success in surgical stabilization of flail chest has been described in small series, but scant evidence exists for this procedure in the orthopaedic literature.
We reviewed 88 ...consecutive patients who underwent surgical stabilization of flail chest, along with 88 consecutive patients with flail chest who underwent traditional closed management before initiation of our algorithm change to surgical management.
Surgical stabilization of flail chest injuries led to statistically significant decreases in hospital length of stay, ventilator-dependency time, pneumonia, tracheostomy, and mortality rate. In addition, the presence of pulmonary contusion did not eliminate the significant improvements in the aforementioned variables.
Surgical stabilization of flail chest with modern techniques and implants provides significant improvements in both mortality and short-term outcomes. Although pulmonary contusion decreased overall outcomes across both cohorts, this factor did not alter the ability of rib fixation to improve outcomes.
Abstract
Age-related decreases in cortical thickness observed during adolescence may be related to fluctuations in sex and stress hormones. We examine this possibility by relating inter-regional ...variations in age-related cortical thinning (data from the Saguenay Youth Study) to inter-regional variations in expression levels of relevant genes (data from the Allen Human Brain Atlas); we focus on genes coding for glucocorticoid receptor (NR3C1), androgen receptor (AR), progesterone receptor (PGR), and estrogen receptors (ESR1 and ESR2). Across 34 cortical regions (Desikan-Killiany parcellation), age-related cortical thinning varied as a function of mRNA expression levels of NR3C1 in males (R2 = 0.46) and females (R2 = 0.30) and AR in males only (R2 = 0.25). Cortical thinning did not vary as a function of expression levels of PGR, ESR1, or ESR2 in either sex; this might be due to the observed low consistency of expression profiles of these 3 genes across donors. Inter-regional levels of the NR3C1 and AR expression interacted with each other vis-à-vis cortical thinning: age-related cortical thinning varied as a function of NR3C1 mRNA expression in brain regions with low (males: R2 = 0.64; females: R2 = 0.58) but not high (males: R2 = 0.0045; females: R2 = 0.15) levels of AR mRNA expression. These results suggest that glucocorticoid and androgen receptors contribute to cortical maturation during adolescence.
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