Distal Extent Research Articles

Knee Capsule Anatomy: An MR Imaging and Cadaveric Study

This research focuses on the anatomical insertion of the synovial capsule around the knee. The attachments of the capsule were measured in 50 knee MR imaging studies with large intraarticular effusion. Corresponding measurements were performed in 20 fresh frozen cadaveric specimens, for validation. Femoral and tibial capsular reflections were defined as the distances between the attachment sites of the capsule and the femoral or tibial joint line and they were recorded in three coronal planes (anterior/middle/posterior). On MR imaging, the lateral/medial femoral capsular reflection mean values were 6.5/4.57 cm, 2.74/1.74 cm and 1.52/1.99 cm in the anterior, middle and posterior plane, respectively. MR imaging-based measurements did not differ significantly compared to corresponding cadaveric measurements. The mean values of the lateral/medial tibial capsular reflection on MR imaging were 0.09/0.11 cm, 0.34/0.26 cm and 0.62/0.34 cm in the anterior, middle and posterior plane, respectively. On cadaveric dissection, the maximum mean value was 1.45 cm, measured on the lateral side of the anterior plane. Apart from the lateral aspect of the posterior plane, MR imaging measurements were significantly lower, compared to the corresponding cadaveric measurements. The greatest femoral and tibial capsular reflections were found on the anterior and lateral side of the anterior plane. MR imaging appears to underestimate the distal extent of the knee capsule. Anatomical details of the knee capsule should be considered for safe insertion of external fixator pins.

A Comparative Study between Nissen's Fundoplication with or without Endoscopic Mucosal Resection in the Treatment of Barrett’s Oesophagus: a Meta-Analysis

Abstract Background It is already known that Barrett’s esophagus (BE) is a premalignant condition in which the normal squamous epithelium of the distal esophagus is replaced by columnar epithelium (intestinal metaplasia or gastric metaplasia) due to GERD. Most observers believe that there is a progression from intestinal metaplasia to low-grade dysplasia (LGD) to highgrade dysplasia (HGD) to cancer. The relative risk of developing esophageal adenocarcinoma in patients with BE appears to be 30-fold higher. Conventional therapies include medical treatment (profound acid inhibition), endoscopic treatment (like endoscopic mucosal resection) and surgical treatment (fundoplication). Methodology Types of studies: Published studies about the efficacy of Nissen’s Fundoplication with or without Endoscopic Mucosal Resection in the treatment of Barrett’s Oesophagus (carried out in the period between 2015 – 2020), types of participants Patients with clinically proven Barrett’s Oesophagus diagnosed by endoscopy and biopsy, types of interventions Nissen’s Fundoplication (Open or Laparoscopic) with or without Endoscopic Mucosal Resection, types of outcome measures Outcome of treatment in the form of Complete Remission of Columnar Metaplasia of the oesophageal mucosa or regression in recurrence rate as proved by follow-up endoscopy. Results The strategy of endoscopic therapy for Barrett’s metaplasia, dysplasia and/or intramucosal cancer along with fundoplication results in similar durability and recurrence rates when compared to patients being managed with PPIs following endoscopic therapy. However, fundoplication along with endoscopic therapy is superior to either of them alone in preventing further progression of disease and the development of cancer, particularly in refractory patients. Fundoplication is an important strategy along with endoscopic therapy for Barrett’s to achieve and maintain CR-IM, and to facilitate the eradication of persistent dysplasia. Conclusion Endoscopic mucosal resection after Nissen's Fundoplication is a safe modality, with high rate of success in complete eradication of BE in symptomatic GERD patients, especially those with severe anatomical impairment in distal esophageal segment. As a concurrent procedure, endoscopic procedures may be beneficial in the terms of reducing the early recurrence rates, which seems to be important issue during the management of BE. By doing synchronous endoscopic procedures and fundoplication, one might observe a true anatomy of esophagogastric junction in its entirety and might be able to truly observe the distal extent of columnar esophagus.

Cerebral protection in type A aortic dissection

: Acute type A aortic dissection (ATAD) carries extremely high morbidity and mortality with a significantly increased risk of cerebrovascular injury following repair compared to elective arch operations. Advancement in operative and neuroprotective strategies have led to a temporal improvement in outcomes, but the incidence of cerebrovascular injury remains high and warrants continued innovation. In the setting of ATAD, stroke can occur due to malperfusion resulting from true lumen compression and compromised cerebral inflow, malperfusion from cardiogenic shock, or embolization. Therefore, stroke mitigation strategies must address vascular obstructions, hemodynamic compromise, and reduce risk of embolization. This article reviews contemporary strategies for cerebral protection in ATAD including preoperative patient evaluation, perfusion and temperature management, extent of aortic repair, utility of cerebral oximetry and neuromonitoring, and pharmacological adjuncts. In summary, patients should be evaluated preoperatively with contrast imaging to fully characterize their dissection to facilitate well-informed operative planning. Cannulation for cardiopulmonary bypass (CPB) can be safely achieved through multiple routes, but should consider patient pathology and the intended approach to cerebral perfusion. Central cannulation is feasible in most patients and allows for the most expeditious initiation of CPB. Although both deep hypothermic circulatory arrest (HCA) with retrograde cerebral perfusion (RCP) and moderate HCA with antegrade cerebral perfusion (ACP) have been shown to provide adequate cerebral protection, targeting moderate hypothermic temperatures reduces CPB times. The combination of a brief period of RCP followed by ACP during moderate HCA allows for the potential flushing of emboli from the cerebral arterial system with the superior metabolic protection of antegrade perfusion. The proximal and distal extent of arch repair should be individually tailored to patient pathology and surgeon experience, making sure to completely resect disease to prevent acute neurological complications. Cerebral oximetry and neuromonitoring are useful adjuncts, providing real-time information about the adequacy of neuroprotection. Finally, co-management by anesthesiologists and perfusionists with administration of neuroprotective agents, appropriate pH management, and maintenance of normal metabolic hemostasis and hemodynamic stability will further minimize cerebrovascular complications. Optimal cerebral protection requires a comprehensive, interdisciplinary approach and implementation of multimodal strategies.

Age-related differences in acute aortic dissection

ObjectiveThe present study investigated the differences in clinical characteristics, treatments, and outcomes of patients with acute aortic dissection (AAD) in different age groups. MethodsThe present single-center retrospective study was conducted from August 2014 to August 2020. The patients were divided into three groups: age <45 years (young group), age 45 to 59 years (middle-age group), and age >59 years (elderly group). Type A (TAAD) and type B (TBAD) aortic dissection were evaluated separately using the latest definitions. ResultsThe mean age at onset was 52.4 years in our cohort of 602 patients. The young group included a large proportion of male patients (86%). The body mass index and body surface area were higher in the young group. The proportion of non–true lumen blood supply of branches on the abdominal aorta in the young group (27%-55%) was greater than that in the others. In the young group, the distal extent of dissection in 84% of TAAD and 89% of TBAD exceeded the abdominal aortic branch cluster (AABC) compared with 36% of TAAD and 58% of TBAD in the elderly group. The multivariate analysis revealed that age <45 years (odds ratio, 5.15; P < .001) and D-dimer level (odds ratio, 1.05; P = .001) were risk factors for intimal flap tear exceeding the AABC. The proportion of visceral and lower limb malperfusion increased from 4.8% to 36.9% as the intimal flap tear exceeded the AABC. ConclusionsCompared with middle-age and elderly patients, young patients with AAD had two characteristics (ie, obesity and an intimal flap that had frequently exceeded the branches of the aorta). These two factors resulted in a greater proportion of non–true lumen blood supply, increased visceral and lower limb malperfusion, and an increase in potential associated risks.

The impact of pre-existing blood pressure control in patients with acute aortic dissections.

Arterial hypertension (HTN) is considered a seminal risk factor for aortic dissection (AD). The purpose of this study is to evaluate whether pre-existing blood pressure (BP) control lessens the extent of dissection and has a favorable impact on outcome of patients with acute AD. Consecutive acute AD patients who had at least two BPs recorded within the 12months preceding the AD were retrospectively analyzed. The two most recent BPs were averaged and defined per published guidelines as normal (BP≤ 130/80), Stage I HTN (BP >130/80 and <139/89), or Stage 2 or greater HTN (BP > 140/90). The number of hypertensive medications (MEDs) was also used as a surrogate marker of HTN severity. Patients with known genetic causes of AD were excluded. 89 subjects (55% men, 45% women; mean age, 64±14years) with acute AD (58% Stanford type A and 42% Stanford type B) were included. Two most recent BPs were recorded a mean of 5±3 and 3±2.7months before the AD, respectively. Twenty-nine (33%) subjects had normal BP, including nine subjects with no history of HTN and on no MEDs. Sixty (67%) subjects had elevated BP, including 21 (35%) with Stage I HTN and 39 (65%) with Stage 2 HTN. Compared to subjects with normal BP, subjects with Stage 1 and Stage 2 HTN were younger (70±13years vs 62±1year, p = 0.01), but there were no differences in other demographics, risk factors, comorbidities, or history of drug use. There were no group differences in the distal extent of the dissections, complications requiring thoracic endograft repair, mean length of hospital stay, final discharge status, or 30-day mortality. Compared to the number of MEDs before AD, all three groups had a higher mean number of MEDs to achieve normal BP at discharge that persisted at a mean follow-up of 18±15months. These data show that approximately one-third of patients with acute AD had well controlled or no antecedent history of HTN. The degree of pre-existing HTN control had no bearing on the type or extent of AD, length of stay, or early outcome. Regardless of the state of HTN control before AD, the consistent and sustained increase in the severity of HTN after AD suggests that the dissection process has a profound and lasting effect on BP regulation. Further studies are indicated to elucidate the pathologic mechanisms involved in AD.

Outcomes and role of peripheral revascularization in type A aortic dissection presenting with acute lower extremity ischemia

ObjectiveLimited data exists on management and outcomes of patients presenting with type A aortic dissection (TAAD) and acute lower extremity ischemia (ALI). The role of limb-related revascularization and optimal treatment strategy remains undefined. The objective of this study was to analyze dissection characteristics, treatment modalities, and outcomes of patients undergoing proximal aortic repair for TAAD with ALI. MethodsConsecutive patients who underwent proximal aortic repair for TAAD were identified from a prospectively maintained database. Clinical data, imaging, operative details, and outcomes of patients with TAAD and ALI were retrospectively analyzed. Kaplan-Meier methodology was used to estimate overall and amputation-free survival. Log-rank tests were used to compare overall curves. Predictors of revascularization and in-hospital mortality were determined using multivariable logistic regression analysis. ResultsFrom 2010 to 2018, 463 patients with TAAD underwent proximal aortic repair. A total of 81 patients (17%) presented with ALI; 48% (39/81) with isolated ALI, and 52% (42/81) with ALI and renovisceral malperfusion. Thirty percent (24/81) required revascularization in addition to proximal aortic repair. Revascularization strategies involved endovascular (46%; 11/24), open (33%; 8/24), and hybrid (21%; 5/24) interventions. The major amputation rate was 4% (3/81), and in-hospital mortality was 21% (17/81). Amputation-free survival was significantly lower in patients requiring revascularization compared with those who did not (log-rank P = .023). Overall survival did not significantly differ between the two groups (log-rank P = .095). Overall survival was significantly lower in patients with concomitant ALI and renovisceral malperfusion compared with those with isolated ALI (log-rank P = .0017). Distal extent of dissection flap into zone 11 (odds ratio [OR], 5.65; 95% confidence interval [CI], 1.58-20.2; P = .008) and partial/complete thrombosis of any iliac artery (OR, 3.94; 95% CI, 1.23-12.6; P = .021) were associated with increased risk of requiring an additional revascularization procedure. True lumen collapse at level of renovisceral aorta (OR, 8.84; 95% CI, 1.74-44.9; P = .0086) was associated with increased risk of in-hospital mortality. ConclusionsALI resolves after proximal aortic repair of TAAD in most cases. Distal extent of aortic dissection into zone 11 and iliac thrombosis are risk factors for additional peripheral revascularization. True lumen collapse at the renovisceral aorta and TAAD with concomitant ALI and renovisceral malperfusion portends a poor prognosis. A multi-disciplinary team approach to manage these patients who present with ascending aortic dissection and distal malperfusion may improve outcomes in this complex population.

Meta-Analysis for Comparison between Antireflux Surgery With or Without Endoscopic Management of Barrett's Esophagus

Abstract Background: In patients with BE, anti-reflux surgery aims to sustainable control reflux symptoms and heal reflux induced esophageal mucosal inflammation and prevent progression of BE to adenocarcinoma. Endoscopic resection of visible lesions if any, followed by ablation of the rest of the BE epithelium is the current standard of care for management of BE with confirmed dysplasia. Although the current literature describes multiple endoscopic and anti-reflux techniques for the management of BE, there is no published evidence on the efficacy of anti-reflux surgery followed by endoscopic man-agement on the outcomes of BE. Aim of Study: The objective of this study was to compare between anti-reflux surgery with or without endoscopic man-agement of BE. Patients and Methods: In the present study, we searched Medline via PubMed, SCOPUS, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), and Google Scholar. The search retrieved 2089 unique records. We then retained 57 potentially eligible records for full-texts screening. Finally, 6 studies were included. Results: In the present systematic review and meta-analysis, five studies reported the rates of recurrence. The overall effect estimates showed the rate of recurrence was 5.7% (95% CI 1.2-10.2%). In the present systematic review and meta-analysis, five studies reported the overall complica-tions rate. The overall effect estimates showed the overall complications rate was 7.3% (95% CI 4.1-10.6%), mainly stricture and perforation. Conclusion: Endoscopic procedures after anti-reflux surgery is a safe modality, with high rate of success in complete eradication of BE in symptomatic GERD patients, especially those with severe anatomical impairment in distal esophageal segment. As a concurrent procedure, endoscopic procedures may be beneficial in the terms of reducing the early recurrence rates, which seems to be important issue during the manage-ment of BE. By doing synchronous endoscopic procedures and fundoplication, one might observe a true anatomy of esophagogastric junction in its entirety and might be able to truly observe the distal extent of columnar esophagus.

Sonographic Location of Distal A1 Pulley by Means of a Bony Acoustic Landmark on the Proximal Phalanx: An Anatomic Study

To identify the anatomic relationship between the distal extent of the A1 pulley and the distalmost insertion point of the palmar plate into the base of the proximal phalanx at a metaphyseal bony ridge, the "P1 peak" (P1P), which is a bony acoustic landmark easily identifiable on sonography of the finger. We studied 48 fingers (no thumbs) from 12 fresh frozen cadavers with high-resolution ultrasound. A 20-gauge hypodermic needle was directed perpendicular to the long axis of the tendon sheath along a plumb line drawn at the level of the bony flare of the proximal metaphyseal-diaphyseal junction of the proximal phalanx, or the P1P, under high-resolution ultrasound guidance. Dissection was then performed, and the distance of the needle barrel and the actual distance of the P1P from the distal edge of the A1 pulley were recorded. The study demonstrated that accurate placement of the needle within 1 mm of the actual P1P was possible using ultrasound guidance and that the P1P was within 1 mm of the distal edge of the actual A1 pulley in all specimens studied. In all the specimens studied, we found that the P1P may be used as a clearly identifiable sonographic reference landmark to identify the distal extent of the A1 pulley. Using the P1P landmark as a guide to judge the completeness of ultrasound-guided percutaneous trigger finger release may reduce the risks of incomplete distal release and inadvertent release of the A2 pulley.

Progradational slope architecture and sediment distribution in outcrops of the mixed carbonate-siliciclastic Bone Spring Formation, Permian Basin, west Texas

AbstractSediment transport and distribution are the keys to understanding slope-building processes in mixed carbonate-siliciclastic sediment routing systems. The Permian Bone Spring Formation, Delaware Basin, west Texas, is such a mixed system and has been extensively studied in its distal (basinal) extent but is poorly constrained in its proximal upper-slope segment. Here, we define the stratigraphic architecture of proximal outcrops in Guadalupe Mountains National Park in order to delineate the shelf-slope dynamics of carbonate and siliciclastic sediment distribution and delivery to the basin. Upper-slope deposits are predominantly fine-grained carbonate lithologies, interbedded at various scales with terrigenous (i.e., siliciclastic and clay) hemipelagic and gravity-flow deposits. We identify ten slope-building clinothems varying from terrigenous-rich to carbonate-rich and truncated by slope detachment surfaces that record large-scale mass wasting of the shelf margin. X-ray fluorescence (XRF) data indicate that slope detachment surfaces contain elevated proportions of terrigenous sediment, suggesting that failure is triggered by changes in accommodation or sediment supply at the shelf margin. A well-exposed terrigenous-rich clinothem, identified here as the 1st Bone Spring Sand, provides evidence that carbonate and terrigenous sediments were deposited contemporaneously, suggesting that both autogenic and allogenic processes influenced sediment accumulation. The mixing of lithologies at multiple scales and the prevalence of mass wasting acted as primary controls on the stacking patterns of terrigenous and carbonate lithologies of the Bone Spring Formation, not only on the shelf margin and upper slope, but also in the distal, basinal deposits of the Delaware Basin.

Oncological outcome of wide anatomic resection with partial mesorectal excision in patients with upper and middle rectal cancer.

The aim was to investigate the influence of distal resection margin and extent of mesorectal excision on long-term oncological outcomes. Consecutive patients with upper and middle third rectal cancer from June 2006 to February 2016 were reviewed. Patients were divided into four groups depending on the distal margin considered as a surrogate marker of the extension of mesorectal excision (Q1 ≤10mm, Q2 11-20mm, Q3 21-30mm, Q4 ≥31mm). Local-recurrence-free survival (LRFS), disease-free survival (DFS) and overall survival (OS) were estimated. Cox regression models were used to investigate the influence of surgical and clinicopathological variables on prognosis by adjusting for confounding factors. Two hundred and eleven patients with mid (125) and upper (86) rectal cancer underwent wide mesorectal excision. The median follow-up was 48.64months (interquartile range 28-63). 17.5% patients developed recurrence. The 5-year LRFS, DFS and OS for all patients were 93.20%, 83.89% and 80.1%, respectively, with no statistically significant differences between groups (LRFS, P=0.601; DFS, P=0.487; OS, P=0.468). In the multivariable analysis the recurrences and survival were associated with the quality of the mesorectum (LRFS, hazard ratio 10.629, 95% CI 2.324-48.610, P=0.002; DFS, hazard ratio 2.789, 95% CI 1.314-5.922, P = 0.008). A wide anatomical resection with partial mesorectal excision and shorter distal resection margin does not jeopardize the oncological outcomes.

Computed Tomography Angiography Assessment of Acute Aortic Syndromes: Classification, Differentiating Imaging Features, and Imaging Interpretation Pitfalls.

An acute aortic syndrome (AAS) is an important life-threatening condition that requires early detection and management. Acute intramural hematoma (IMH), aortic dissection (AD) and penetrating atherosclerotic ulcer (PAU) are included in AAS. ADs can be classified using the well-known Stanford or DeBakey classification systems. However, these classification systems omit description of arch dissections, anatomic variants, and morphologic features that impact outcome. The Society for Vascular Surgery and Society of Thoracic Surgeons (SVS-STS) have recently introduced a classification system that classifies ADs according to the location of the entry tear (primary intimomedial tear, PIT) and the proximal and distal extent of involvement, but does not include description of all morphologic features that may have diagnostic and prognostic significance. This review describes these classification systems for ADs and other AAS entities as well as their limitations. Typical computed tomography angiography (CTA) imaging appearance and differentiating features of ADs, limited intimal tears (LITs), IMHs, intramural blood pools (IBPs), ulcer-like projections (ULPs), and PAUs will be discussed. Furthermore, this review highlights common imaging interpretation pitfalls, what should be included in a comprehensive CTA report, and provides a brief overview of current management options.

Application of deep hypothermic circulatory arrest in open left chest aortic aneurysm repair

ObjectivesDeep hypothermic circulatory arrest (DHCA) is often required for patients undergoing repair of descending thoracic aortic aneurysm (DTAA) or thoracoabdominal aortic aneurysm via left thoracotomy when proximal crossclamping is not feasible or when aneurysmal disease extends into the transverse aortic arch. Historical literature suggests higher complications rates due to the technical complexity of this approach; we examined outcomes with this approach at our center. MethodsBetween January 2008 and May 2018, 84 patients with DTAA or Crawford extent I thoracoabdominal aortic aneurysm underwent open repair. DHCA was employed in 46 of 84 (55%) patients, of which 33 (72%) required repair of distal arch and DTAA, and 13 (28%) required repair of the distal arch and extent I thoracoabdominal aortic aneurysm. Patients who underwent DHCA had more chronic dissections than those in the non-DHCA group (70% vs 34%; P ≤ .05). ResultsMajor adverse outcomes for the DHCA group versus non-DHCA group were as follows: early mortality 3 out of 46 (7%) versus 4 out of 38 (11%) (P = .70), stroke 3 out of 46 (7%) versus 1 out of 38 (3%) (P = .62), permanent spinal cord deficit 2 out of 46 (4%) versus 3 out of 38 (8%) (P = .65), permanent renal failure necessitating dialysis 1 out of 46 (2%) versus 2 out of 38 (5%) (P = .59). Freedom from major adverse outcomes was 38 out of 46 (83%) versus 31 out of 38 (82%) for DHCA versus non-DHCA (P = 1). ConclusionsDHCA can be employed via left thoracotomy for combined arch and DTAA or extent I thoracoabdominal aortic aneurysm open repair.

A Novel Percutaneous Modified Brostrom-Gould Technique for Lateral Ankle Instability Using the Lasso Technique

We describe a percutaneous modification of the Brostrom-Gould procedure for lateral ankle instability. Our surgical technique involves making a stab incision at the anterior aspect of the distal fibula. Dissection is made down to bone and a double-loaded suture anchor is placed at the anterior talofibular ligament (ATFL) origin. The sutures are loaded individually onto a trocar needle and passed underneath the remnant ATFL and inferior extensor retinaculum at its distal extent. Percutaneous stab incisions are made to allow retrieval of the sutures which are passed subcutaneously back to the ATFL origin. The 2 sets of sutures, positioned to reconstruct the ATFL and calcaneofibular fibular ligament, are then secured with the ankle in eversion and plantigrade position. Patients are placed on a short walker boot and 2 to 3 weeks of non–weight-bearing postoperatively. Level of Evidence: Level V—Expert opinion. See Instructions for Authors for a complete description of levels of evidence.

Predicting Syndesmotic Injury in OTA/AO 44-B2.1 (Danis-Weber B) Fractures.

To establish if preoperative radiographs could predict the rate of syndesmotic injury. Level 1 trauma center. Retrospective cohort study. There were 548 OTA/AO 44-B2.1 fractures that were reviewed, and 287 patients were included in the study. Ankle radiographs were used to determine the zone of distal extent of the proximal fracture fragment. Syndesmotic injury was defined as positive intraoperative stress examination that required syndesmotic fixation. There were 191 zone 1 (ending below the plafond) injuries, 57 zone 2 (ending between the physeal scar and the plafond) injuries, and 39 zone 3 (ending above the physeal scar) injuries. Of these, 17% (33 patients) of zone 1, 42% (24) of zone 2, and 74% (29) of zone 3 fractures had syndesmotic injuries. The relative risk of syndesmotic injury of zone 1 compared with zone 2 was 2.4 (P < 0.001), zone 1 to zone 3 was 4.3 (P < 0.001), and zone 2 to zone 3 was 1.8 (P = 0.002). The interobserver and intraobserver reliability was excellent (κ = 0.86, 0.94). OTA/AO 44-B2.1 fractures have a varying rate of syndesmotic injury. Weber B fractures that end between the level of the plafond and the physeal scar (zone 2) are 2.4 times more likely to have a syndesmotic injury compared with those that end below the plafond (zone 1). This is magnified in those injuries ending above the scar (zone 3). This simple classification of OTA/AO 44-B2.1 fractures is predictive of syndesmotic injury and may aid in preoperative counseling and planning. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Novel Abdominal Decompression Technique to Treat Compartment Syndrome After Burn Injury

BackgroundPrevalence of abdominal compartment syndrome (ACS) is estimated to be 4%-17% in severely burned patients. Although decompressive laparotomy can be lifesaving for ACS patients, severe complications are associated with this technique, especially in burn populations. This study outlines a new technique of releasing intraabdominal pressure without resorting to decompressive laparotomy. Materials and methodsTen fresh tissue cadavers were studied; none of whom had had prior abdominal surgery. Using Veress needles, abdomens were insufflated to 30 mm Hg and subsequently connected to arterial pressure transducers. Two techniques were then used to incise fascia. First, large skin flaps were raised from a midline incision (n = 5). Second, small 2 cm cutdowns at the proximal and distal extent of midaxillary, subcostal, and inguinal incisional sites were made, followed by tunneling a subfascial plane using an aortic clamp with fascial incisions made through the grooves of a tunneled vein stripper (n = 5). Pressures were recorded in the sequence of incisions mentioned previously. ResultsThe open midline flap technique decreased abdominal pressure from a mean pressure of 30 ± 1.8 mm Hg to 6.9 ± 5.0 mm Hg (P < 0.01). The minimally invasive technique decreased intraabdominal pressure from 30 ± 0.9 to 5.8 ± 5.2 mm Hg (P < 0.01). This technique significantly reduced intraabdominal pressure via extraperitoneal component separation and fascial release at the midaxillary, subxiphoid, and inguinal regions. ConclusionsThis technique offers the benefit of reducing the morbidity, mortality, and complications associated with an open abdomen, which may be beneficial in the burn injury population.

Patterns Of Failure After Adjuvant Radiation For Meningioma, Radiologic Assessment To Inform Target Delineation And Treatment Planning

Adjuvant radiotherapy is increasingly used for intermediate and high-risk meningioma, and although short-term results from prospective trials demonstrate good rates of local control, long-term failures remain common. Moreover, the optimal expansions for postoperative radiotherapy target delineation for meningioma are unknown. We sought to elucidate the patterns of failure after adjuvant radiotherapy for meningioma to inform target delineation and treatment planning. Patients undergoing surgical resection for meningioma at a single institution were retrospectively reviewed for treatment with adjuvant radiation therapy, including external beam radiation therapy (EBRT), stereotactic radiosurgery (SRS), or brachytherapy. Patients treated with EBRT were evaluated for patterns of failure based on MRI review, and were classified as resection cavity, dural margin, osseous craniotomy tract, and intraparenchymal brain. Analysis was performed to evaluate factors associated with each failure type, and to identify the radiologic distance from the resection cavity margin to the furthest margin of each site of recurrent disease. From 1991 to 2015, 71 patients with 86 lesions were treated with adjuvant radiation therapy after resection of meningioma. The median follow-up was 4.2 years (IQR: 1.5-8.4 years). There were 14 (16%) grade 1, 49 (57%) grade II, and 23 (27%) grade III meningiomas, and gross total resection was achieved in 53 (61.6%) of cases. There were 22 local failures after EBRT, 16 (72.7%) were in-field, 11 (50%) were at the dural margin, 2 (9.1%) were along a craniotomy track, and 2 (9.1%) were intraparenchymal. In patients with dural marginal failure, the median distance from the edge of the resection cavity to the distal extent of the recurrence was 15 mm (IQR: 13-24 mm). Of the resection cavity recurrences, 5 (31.2%) occurred within 10 mm of the apex of the orbit or the cavernous sinus. The median MIB1 labeling index in meningioma with either intraparenchymal or craniotomy tract failure was 31.0%, compared to 11.3% (p = 0.018) in patients with infield or dural margin failure. Local failure along the dural margin after adjuvant radiation therapy for meningiomas occurred a median of 15 mm from the resection cavity. Failure along the craniotomy tract or parenchymal brain was uncommon, and was associated with a significantly higher MIB1, likely reflecting more aggressive tumor biology. These data may help to inform target delineation and margin expansion for patients receiving adjuvant radiotherapy for meningioma.

A Cadaveric Study of the Distal Biceps Femoris Muscle in relation to the Normal and Variant Course of the Common Peroneal Nerve: A Possible Cause of Common Peroneal Entrapment Neuropathy.

The most frequent mononeuropathy in the lower extremity has been reported as the common peroneal nerve entrapment neuropathy (CPNe) around the head and neck of the fibula, although the mechanism of the neuropathy in this area cannot be fully explained. Therefore, the aim of this cadaveric study was to evaluate the relationship between morphologic variations of the distal biceps femoris muscle (BFM) and the course of the common peroneal nerve (CPN) and to investigate the incidence and morphological characteristics of anatomical variations in the BFM associated with CPNe. The popliteal region and the thigh were dissected in 115 formalin-fixed lower limbs. We evaluated consensus for (1) normal anatomy of the distal BFM, (2) anatomic variations of this muscle, and (3) the relationship of the muscle to the CPN. Measurements of the distal extents of the short and long heads of the BFM from insertion (fibular head) were performed. Two anatomic patterns were seen. First, in 93 knees (80.8%), the CPN ran obliquely along the lateral side of the BFM and then superficial to the lateral head of the gastrocnemius muscle. Second, in 22 cases (19.2%), the CPN coursed within a tunnel between the biceps femoris and lateral head of the gastrocnemius muscle (LGCM). There was a positive correlation between the distal extents of the short heads of the biceps femoris muscle (SHBFM) and the presence of the tunnel. The “popliteal intermuscular tunnel” in which the CPN travels can be produced between the more distal extension variant of the SHBFM and the LGCM. This anatomical variation of BFM may have a clinical significance as an entrapment area of the CPN in the patients in which the mechanism of CPNe around the fibula head and neck is not understood.

Intravascular extension of Wilms tumor: Characteristics of tumor thrombus and their impact on outcomes

Studies describing intravascular involvement in Wilms tumor have focused on illustrating individual institutional experience and the elements of surgical management. Thrombus characteristics like extent, patterns of regression, and correlation with the surgical findings, intraluminal adhesion, and viable tumor in the thrombus, and patency of the inferior vena cava (IVC) have not been systematically described. The aim of this study is to evaluate these thrombus characteristics and explore their impact on the overall outcomes. All patients with histologically confirmed Wilms tumors with intravascular thrombus diagnosed in the pediatric oncology unit of Tata Memorial Hospital registered from 2006 to 2019 were included. Data regarding clinical, radiological, and surgical particulars were retrieved from the prospectively maintained institutional database. Specific data for the thrombus included: distal extent before and after neoadjuvant chemotherapy, correlation of extent with the surgical findings, completeness of thrombectomy, the presence of a viable tumor in the thrombus, and the patency of the IVC. Survival analysis was performed utilizing the Kaplan-Meier method on SPSS software version 25. The study included 43 (9.9%) of the 432 patients with Wilms tumor having intravascular extension. Retrohepatic IVC (33.3%) followed by atrioventricular (26%) formed the frequent levels of thrombus with maximum regression occurring after chemotherapy in the latter (Summary figure). The overall concordance rate between computed tomography (CT) scan and surgical findings for the presence of thrombus was 86% and 4 patients had the thrombus limited to a lower level than the preoperative scan. At a median follow-up of 5-years, the 5-year event-free and overall survival was 81% and 82.2% respectively. Atrioventricular thrombus (p=0.003) and postoperative patency of IVC (p=0.02) were significantly associated with inferior survival, while the extent of regression, thrombus fracture, and viability was not significant. The findings of this study bring forth the characteristics of intravascular tumor thrombus affecting the outcomes which can be validated in future prospective studies. Although the ideal method for radiological assessment of the intravascular thrombus is elusive, CT scan provided adequate information for the presence and level of the intravascular thrombus with reasonable accuracy in this study. Study limitations include small sample size, the limited number of events, and lack of multivariate analysis to rule out confounding factors that could influence the observed findings. Atrioventricular thrombus and occlusion of IVC represent adverse prognostic factors. The extent of regression, fracture, and viability of thrombus did not affect survival in this study.

The Effect of Hypogastric Artery Revascularization on Ischemic Colitis in Endovascular Aneurysm Repair

BackgroundThe objective of the study was to examine the effect of hypogastric revascularization maneuvers on the rate of postoperative ischemic colitis among patients undergoing endovascular aortoiliac aneurysm repair. MethodsUsing the 2011-2018 Endovascular Aneurysm Repair Procedure-Targeted American College of Surgeons National Surgical Quality Improvement Program Participant Use Files, we analyzed patients undergoing elective endovascular infrarenal aortoiliac aneurysm repairs. Using multivariable modeling techniques, a cohort of patients at high risk for postoperative ischemic colitis was identified. The outcomes of this group were then compared using Pearson's chi-square testing in accordance with whether or not they underwent hypogastric revascularization. ResultsOf 4753 patients undergoing endovascular aortoiliac aneurysm repair in the National Surgical Quality Improvement Program cohort, 1161 had concomitant hypogastric revascularization procedures. High-risk predictors of ischemic colitis included chronic obstructive pulmonary disease and concurrent renal artery or external iliac artery stenting. There was not a significant association between pelvic revascularization and postoperative ischemic colitis [1.0% with versus 0.5% without pelvic revascularization; adjusted odds ratio of ischemic colitis with revascularization 2.07 (0.96, 4.46); P = 0.06] after adjustment for patient- and procedure-related factors. In a subgroup analysis of patients with a distal aneurysm extent beyond the common iliac artery, the incidence of ischemic colitis was significantly lower in patients without pelvic revascularization (0.1% versus 1.6%, P = 0.004). ConclusionsOur analysis of patients undergoing elective endovascular repair of infrarenal aortoiliac aneurysmal disease did not find a reduced incidence of postoperative ischemic colitis in patients who received a concomitant pelvic revascularization procedure, suggesting instead that such procedural adjuncts may actually increase risk for this complication.

Predicting Syndesmotic Injury in Weber B Ankle Fractures

Category:Trauma; AnkleIntroduction/Purpose:Accurate pre-operative diagnosis of syndesmotic injuries can be difficult in the setting of AO 44-B1 fractures. Ankle fractures with syndesmotic injuries have worse reported outcomes. No study has investigated the relative fracture height in determining potential syndesmotic injury. The goal of this study was to establish if pre-operative radiographs could accurately predict syndesmotic injury.Methods:Patients treated for an isolated AO 44-B1 fracture over a ten-year period (2007-2017) were reviewed. Anteroposterior and mortise views of the ankle were used to determine the zone of distal extent of the proximal fracture fragment (Figure 1). Syndesmotic injury was defined as positive intraoperative stress exam that required syndesmotic fixation. Relative risks were determined between zones with a statistical significance set at 0.05. Ten randomly selected radiographs were reviewed by two authors and assessed by intra-class correlation (ICC) for inter- and intra-observer reliability.Results:There were 548 AO 44-B1 fractures that were reviewed; and 287 patients were included in the study. There were 191 zone 1 injuries, 57 zone 2 injuries, and 39 zone 3 injuries. Of these, 17% (33 patients) of zone 1, 42% (24) of zone 2, and 74% (29) of zone 3 fractures had syndesmotic injuries. The relative risk of syndesmotic injury of Zone 1 compared to Zone 2 was 2.4 (p<0.001), Zone 1 to Zone 3 was 4.3 (p<0.001), Zone 2 to Zone 3 was 1.8 (p=0.002). The ICC for inter- and intra-observer reliability was perfect (ICC=1).Conclusion:AO 44-B1 fractures have a varying rate of syndesmotic injury. Weber B fractures that end between the level of the plafond and the physeal scar (Zone 2) are 2.6 times more likely to have a syndesmotic injury compared to those that end below the plafond (Zone 1). This is magnified in those injuries ending above the scar (Zone 3). This simple classification of AO 44-B1 fractures is predictive of syndesmotic injury and may aid in preoperative counseling and planning.