Blunt popliteal artery injury following tibiofemoral trauma: vessel-first and bone-first strategy

Purpose: Blunt popliteal artery injury (BPAI) is a potentially limb-threatening sequela of tibiofemoral (knee) dislocations and fractures. Associated amputation rates for all popliteal artery (PA) injuries range between 10 and 50%. It is unclear whether PA repair or bone stabilization should be performed first. We analyzed (long-term) clinical outcomes of BPAI patients that received initial PA repair (vessel-first, VF) versus initial external stabilization (bone-first, BF). Methods: Retrospectively, all surgically treated BPAI patients between January 2000 and January 2019, admitted to two level 1 trauma centers were included. Clinical outcomes were determined, stratified by initial management strategy (VF and BF). Treatment strategy was determined by surgeon preference, based on associated injuries and ischemia duration. Primary outcomes (amputation and mortality) and secondary outcomes (claudication and complications) were determined. Results: Of 27 included BPAI patients, 15 were treated according to the VF strategy (56%) and 12 according to the BF strategy (44%). Occlusion was the most frequently encountered BPAI in 18/27 patients (67%). Total delay and in-hospital delay were comparable between groups (p = 1.00 and p = 0.82). Revascularization was most frequently performed by PA bypass (59%). All patients had primary limb salvage during admission (100%). One secondary amputation due to knee pain was performed in the BF group (4%). During a median clinical follow-up period of 2.7 years, three PA re-interventions were performed, two in the BF group and one in the VF group. None suffered from (intermittent) claudication. Conclusion: Blunt popliteal artery injury (BPAI) is a rare surgical emergency. Long-term outcomes of early revascularization for BPAI appear to be good, independent of initial management strategy. The BF strategy may be preferred in case of severe orthopedic injury, if allowed by total ischemia duration

Contextual factors affecting the integration of community health workers into the health system in Limpopo Province, South Africa

BACKGROUND: Community health workers (CHWs) are an essential cadre in the health systems of many low- and middle-income countries. These workers provide a wide variety of services and are key to ongoing processes of task shifting within human immunodeficiency virus programmes in particular. Ward-based outreach teams (WBOTs) are South Africa’s latest iteration of the CHW programme and have been introduced as part of the National Department of Health’s Primary Health Care Re-engineering programme. METHODS: In order to assess the perceived effectiveness of the WBOTs in supporting the ongoing rollout of antiretroviral therapy, tuberculosis care and patient support, we conducted a qualitative investigation focusing on the perceived successes and challenges of the programme among CHWs, community leaders, healthcare workers and community members in the Mopani district, Limpopo province, South Africa. RESULTS: The CHW programme operates across these contexts, each associated with its own set of challenges and opportunities. CONCLUSIONS: While these challenges may be interrelated, a contextual analysis provides a useful means of understanding the programme’s implementation as part of ongoing decision-making processes.The American people through the US President’s Emergency Plan for AIDS Relief through the US Agency for International Development (USAID) under cooperative agreement 674-A-12-00015 to the Anova Health Institute. This research project was supported by a postgraduate training scholarship from the Fogarty International Center and National Institute of Allergy and Infectious Diseases (NIAID), the University of North Carolina–University of the Witwatersrand (UNC-Wits) AIDS Implementation Science and Cohort Analyses Training Grant (5D43TW009774-02).https://academic.oup.com/inthealthpm2021Medical Microbiolog

Complex Langevin: Etiology and Diagnostics of its Main Problem

The complex Langevin method is a leading candidate for solving the so-called sign problem occurring in various physical situations. Its most vexing problem is that in some cases it produces `convergence to the wrong limit'. In the first part of the paper we go through the formal justification of the method, identify points at which it may fail and identify a necessary and sufficient criterion for correctness. This criterion would, however, require checking infinitely many identities, and therefore is somewhat academic. We propose instead a truncation to the check of a few identities; this still gives a necessary criterion, but a priori it is not clear whether it remains sufficient. In the second part we carry out a detailed study of two toy models: first we identify the reasons why in some cases the method fails, second we test the efficiency of the truncated criterion and find that it works perfectly at least in the toy models studied.Comment: 39 pages, 15 figures; typos corrected and reference adde

Blunt cerebrovascular injury: incidence and long-term follow-up

PURPOSE: Blunt cerebrovascular injuries (BCVI), which can result in ischemic stroke, are identified in 1-2% of all blunt trauma patients. Computed tomography angiography (CTA) scanning has improved and is the diagnostic modality of choice in BCVI suspected patients. Data about long-term functional outcomes and the incidence of ischemic stroke after BCVI are limited. The aim of this study was to determine BCVI incidence in relation to imaging modality improvements and to determine long-term functional outcomes. METHODS: All consecutive trauma patients from 2007 to 2016 with BCVI were identified from the level 1 trauma center prospective trauma database. Three periods were identified where CTA diagnostic modalities for trauma patients were improved. Long-term functional outcomes using the EuroQol six-dimensional (EQ-6D™) were determined. RESULTS: Seventy-one BCVI patients were identified among the 12.122 (0.59%) blunt trauma patients. In the first period BCVI incidence among the overall study cohort, polytrauma, basilar skull fracture and cervical trauma subgroups was found to be 0.3%, 0.9%, 1.2%, 4.6%, respectively, which more than doubled towards the third period (0.8, 2.4, 1.9 and 8.5% respectively). Ischemic stroke as a result of BCVI was found in 20 patients (28%). In-hospital stroke rate was lower in patients receiving antiplatelet therapy (p < 0.01). Six in-hospital deaths were BCVI related. Long-term follow-up (follow-up rate of 83%) demonstrated lower functional outcomes compared to Dutch reference populations (p < 0.01). Ischemic stroke was identified as a major cause of functional impairment at long-term follow-up. CONCLUSIONS: Improved CTA diagnostic modalities have increased BCVI incidence. Furthermore, BCVI patients reported significant functional impairment at long-term follow-up. Antiplatelet therapy showed a significant effect on in-hospital stroke rate reduction

The influence of frontal alignment in the advanced reciprocating gait orthosis on energy cost during paraplegic gait

Reduction of energy cost and upper body load during paraplegic walking is considered to be an important criterion in future developments of walking systems. A high energy cost limits the maximum walking distance in the current devices, whereas wrist and shoulder pathology can deteriorate because of the high upper body load. A change in alignment of the mechanical brace in the frontal plane, i.e. abduction, can contribute to a more efficient gait pattern with sufficient foot clearance with less pelvic lateral sway. A decrease in pelvic lateral sway after aligning in abduction results in a shift of the centre of mass to the swing leg crutch which may result in a decrease in required crutch force on stance side to maintain foot clearance. Five paraplegic subjects were provided with a standard Advanced Reciprocating Gait Orthosis (ARGO) and an ARGO aligned in 4 different degrees of abduction (0°, 3°, 6° and 9°). After determining an optimal abduction angle for each of the subjects, a cross over design was used to compare the ARGO with the individually optimised abducted orthosis. An abduction angle between 0° and 3° was chosen as optimal abduction angle. Subjects were not able to walk satisfactory with abduction angles 6° and 9°. A significant reduction in crutch peak force on stance side was found (approx. 12% , p < 0.01) in the abducted orthosis. Reduction in crutch force time integral (15%) as well as crutch peak force on swing side (5%) was not significant. No differences in oxygen uptake as well as oxygen cost was found. We concluded that an abduction angle between 0° and 3° is beneficial with respect to upper boHy load, whereas energy requirements did not change

Intracerebral steal phenomenon in symptomatic carotid artery disease

Background and purpose: Intracerebral steal is a paradoxical vasodilatory response that reduces cerebral blood flow (CBF) in hemodynamically compromised brain tissue when blood is rerouted to more healthy areas. The aim of our study was to investigate the presence and extent of steal in patients with steno-occlusive internal carotid artery (ICA) disease, and to assess its relation with collateral blood flow through the circle of Willis (CoW). Materials and methods: Thirty-eight patients with symptomatic steno-occlusive ICA disease underwent MRI examination with arterial spin labeling (ASL) perfusion imaging before and after a vasodilatory challenge. Intracerebral steal was defined as a decline in CBF after acetazolamide. Collateral flow via the CoW was assessed with time-of-flight and flow direction MR angiography (MRA) through the CoW was assessed with 2D phase-contrast MRA's. Results: Eight of 38 patients (21%) had steal in the hemisphere ipsilateral to the symptomatic ICA (mean tissue volume with steal, 6.9 ± 4.1 mL; mean CVR, −11 ± 30%). Cerebrovascular reactivity (CVR) was lower in the middle cerebral artery flow territory of the affected hemisphere in patients with steal compared those without (P = 0.002). Collateral blood flow was impaired in 4 of the 8 patients with steal. These patients had a larger area of steal (P = 0.002). Conclusions: Intracerebral steal occurs in patients with obstructive ICA disease and can be assesses at brain tissue level with ASL perfusion MRI. Its presence is related to more severely declined CVR in the surrounding brain tissue area and the volume is associated with impaired primary collateral blood flow through the CoW

Making ward-based outreach teams an effective component of human immunodeficiency virus programmes in South Africa

The implementation of ward-based outreach teams (WBOTs), comprised of community health workers (CHWs), is one of the three interventions of the South African National Department of Health’s (NDoH) Primary Health Care (PHC) Re-engineering strategy for improving health outcomes. CHWs provide a necessary structure to contribute to successful implementation of the human immunodeficiency virus (HIV) programme in four ways: (1) prevention of HIV infection by health education, (2) linkage to care by health education and referrals, (3) adherence support and (4) identification of individuals who are failing treatment. However, CHW programme and HIV programme-specific barriers exist that need to be resolved in order to achieve maximum impact. These include a lack of stakeholder and community support for WBOTs, challenging work and operational environments, a lack of in-depth knowledge and skills, and socio-cultural barriers such as HIV-related stigma. Considering its promising structure, documentation of the WBOT contribution to healthcare overall, and the HIV programme in particular, is urgently warranted to successfully and sustainably incorporate it into the South African healthcare system