National Trends and Outcomes of Pedal Bypass Surgery.

OBJECTIVE: The technical demands associated with pedal bypass (PB) surgery place it at risk of underutilization and may be limiting its widespread adoption as a valuable revascularization modality. This study aims to evaluate trends in PB performance, assess its outcomes, and compare its results between high- and low-volume centers. METHODS: All patients receiving a PB between 2003 and 2023 were identified in the Vascular Quality Initiative (VQI) infrainguinal bypass (IIB) module. The ratio of PB to total IIB performed was calculated for each year and trended over the study period. Centers performing PB were categorized according to their annual PB volume into tertiles of low-volume centers (LVC, <2 PB/year), medium-volume centers (MVC, 2-4 PB/year), and high-volume centers (HVC, >4 PB/year) for comparison. Patient characteristics and outcomes were compared using the χ2 or Fisher exact test as appropriate for categorical variables and the analysis of variance test or Kruskal-Wallis test as appropriate for continuous variables. Cox regression analysis was used to study the association between center volume and the primary outcomes of primary patency, primary-assisted patency, secondary patency, reintervention, amputation, and major adverse limb events (MALE), defined as the composite outcome of amputation and/or reintervention. RESULTS: A total of 3466 patients received a PB during the study period. The ratio of PB to IIB dropped from 14% to 4% between 2003 and 2023. Primary, primary-assisted, and secondary patency rates were 65%, 76%, and 80%, respectively, and limb salvage rate was 83% at 1 year. Nineteen percent of centers performing IIBs in the VQI did not perform any PBs during the study period. Of the 246 centers performing PBs, 78% were LVC, 15% were MVC, and only 7% were HVC. On Cox regression analysis, HVCs were associated with a lower risk of primary patency loss (hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.66-0.95; P = .010), reintervention (HR, 0.75; 95% CI, 0.60-0.95; P = .016), amputation (HR, 0.77; 95% CI, 0.61-0.98; P = .034), and MALE (HR, 0.78; 95% CI, 0.66-0.93; P = .005) compared with LVCs. No difference in secondary patency between high- and low-volume centers was observed (P = .680). CONCLUSIONS: The utilization of PB operations experienced a four-fold decrease over the past 20 years, despite favorable patency and limb salvage outcomes. Centers with a higher operative volume in PB achieve better outcomes than LVCs, and accordingly, patients with extensive tibioperoneal disease may benefit from evaluation at centers with documented expertise in PB before resorting to an alternative revascularization modality or a major limb amputation.

Effects of Small and Normalized Q-Factor Changes and Knee Alignment on Knee Biomechanics during Stationary Cycling.

Increasing inter-pedal distance (Q-Factor: QF) in cycling increases peak internal knee abduction moments (KAbM). The effect of smaller and normalized changes in QF has not been investigated. The purposes of this study were to examine changes in KAbM with small and normalized increases and whether static knee alignment accounts for any changes in knee biomechanics in cycling. Fifteen healthy participants were included (age: 22.7 ± 2.5 years, BMI: 23.95 ± 3.21 kg/m2). Motion capture and instrumented pedals collected kinematic and pedal reaction force (PRF) data, respectively, while participants cycled at five different QFs. Each participant's mechanical axis angle (MAA) was estimated using motion capture. Each participant's QFs were normalized by starting at 160 mm and increasing by 2% of the participant's leg length (L), where the five QF conditions were as follows: QF1 (160), QF2 (160 + 0.02 × L), QF3 (160 + 0.04 × L), QF4 (160 + 0.06 × L), and QF5 (160 + 0.08 × L). A linear mixed model was performed to detect differences between QF conditions. KAbM increased by more than 30% in QF5 from QF1, QF2, QF3, and QF4. Medial PRF increased by at least 20% in QF5 from QF1, QF2, and QF3. MAA had varying degrees of correlation with the variables of interest. These results suggest that KAbM is more sensitive to changes in QF at greater QF increases.

The Accuracy and Reliability of the Power Measurements of the TACX Neo 2T Smart Trainer and Its Agreement against the Garmin Vector 3 Pedals.

The power output in cycling is one of the most important factors for athletes and coaches. The cycling community has several commercial gears that can be used. One of the most used is the TACX Neo 2T (TN2T) smart trainer. The objective of this study was to investigate the metrological proprieties of the TN2T (accuracy and reliability), as well as its agreement with the Garmin Vector 3 (GV3) pedals at different power stages. The sample consisted of ten regional-level cyclists with a mean age of 45.6 ± 6.4 years, who regularly participated in regional and national competitions. Residual relative differences were found between the two devices. Both devices showed good reliability with coefficients of variation and intraclass correlation coefficients ranging from 0.03% to 0.15% and from 0.731 to 0.968, respectively. Independent samples t-test comparison between devices showed no significant differences in all power stages (p > 0.05). Bland-Altman plots showed that more than 80% of the plots were within the 95% confidence intervals in all power stages. The present data showed that there were non-significant differences between the two devices at power stages between 100 W and 270 W, with a strong agreement. Therefore, they can be used simultaneously.

Does Blacklight Illumination Improve Speed and Accuracy of Foot Pedal Activation in the Low-Light Operating Room?

Background: Urologists frequently activate foot pedals in a low-light operating room (OR). Pedal activation in low-light conditions poses the potential for incorrect pedal activation, potentially leading to increased radiation exposure, patient burns, or OR fires. This study compares speed, accuracy, dark adaptation, and surgeon preference for pedal activation in 4 lighting conditions. Materials and Methods: During a simulated percutaneous nephrolithotomy (PCNL), pedals for C-arm, laser, and ultrasonic lithotripter (USL) were randomized to 3 different positions. Urology attendings, residents, and medical students activated pedals in a randomized order in 4 settings: a dark OR with no illumination, an OR with overhead illumination, a dark OR with glowstick illumination, and a dark OR with blacklight illumination. Endpoints included pedal activation time; number of attempted, incomplete, and incorrect activations; dark adaptation; and subjective pedal preference. ANOVA was used for analysis with p < 0.05 considered significant. Results: In our study with 20 participants, the mean pedal activation times were significantly faster when using glowstick illumination (6.77 seconds) and blacklight illumination (5.34 seconds) compared with the no illumination arm (8.47 seconds, p < 0.001). Additionally, individual pedal activations for the C-arm, laser, and USL were significantly faster with glowstick and blacklight illumination compared with a dark OR (p < 0.001 for all). The blacklight illumination arm demonstrated decreased attempted (0.30 vs. 3.45, p < 0.001), incomplete (1.25 vs. 7.75, p < 0.001), and incorrect activations (0.35 vs. 1.25, p < 0.001) compared with the dark setting, while demonstrating no difference compared with having room lights on. Dark adaptation was significantly improved with blacklight illumination compared with having the room lights on (134.5 vs. 140.5 luminance, p < 0.001). All participants (100%) preferred illuminated pedals compared with the dark OR, with 90% favoring the blacklight illumination. Conclusions: During a simulated PCNL, blacklight illumination significantly improved accuracy and efficiency of pedal activation compared with the conventional dark OR, while maintaining the surgeon's dark adaptation.

Ultrasonic Doppler as a guide for feline peripheral arterial catheterization.

OBJECTIVES: The study aimed to determine if an ultrasonic Doppler-guided technique (UDGT) leads to improved placement efficacy (time, success) of feline dorsal pedal arterial catheters vs the traditional palpation-guided technique (TPT). METHODS: A total of 26 adult, client-owned cats requiring sedation or general anesthesia for any reason, aged >12 months and weighing >3.0 kg, and with Doppler blood pressure measurements of at least 80 mmHg were enrolled. Each hindlimb was randomly assigned for dorsal pedal arterial catheterization using either the UDGT or TPT. With the UDGT, the location of the artery was identified by an audible sound using the Doppler. Successful catheter placement was confirmed by visualization of an arterial pressure waveform using a transducer and monitor system attached to the catheter. The Kaplan-Meier method and log-rank test were used to compare the two techniques. RESULTS: The overall proportion of successful arterial catheterization was 17% (9/52): 19% (5/26) via UDGT and 15% (4/26) via TPT. Among successful arterial catheterizations (n = 9), the mean time to catheterization was 339 ± 198 s: 328 ± 237 s (n = 5) with UDGT and 353 ± 171 s (n = 4) with TPT. The log-rank test showed the two techniques were not significantly different in likelihood of successful arterial catheter placement or time to successful catheterization (P = 0.698). An arterial flash occurred in 62% (32/52) of the limbs, 58% (15/26) with the UDGT and 65% (17/26) with the TPT. Complications (self-limiting bruising, hematoma formation) were observed equally between UDGT (3/26 limbs) and TPT (3/26 limbs) in six cats. CONCLUSIONS AND RELEVANCE: The UDGT did not improve the efficacy of catheter placement compared with the TPT. Few complications were associated with arterial catheterization.

The impact of angiographic pedal circulation status on wound healing in chronic limb-threatening ischemia after bypass surgery.

OBJECTIVE: In the treatment of chronic limb-threatening ischemia (CLTI), complete wound healing is an important goal. Although foot perfusion status seems to be important for wound healing, the Global Limb Anatomic Staging System (GLASS) of the Global Vascular Guidelines does not include pedal artery status for the staging process due to the lack of sufficient evidence of its importance. This study aimed to clarify the importance of pedal perfusion status after bypass surgery. METHODS: Among the 153 CLTI cases that underwent bypass distal to popliteal arteries from 2014 to 2018, 117 CLTI limbs with wounds and with sufficient pedal angiographic data were enrolled. They were classified into two groups, based on the wound status 6 months postoperatively; early wound healing group (EWG; n = 78), which achieved complete wound healing within 6 months postoperatively, and prolonged healing or unhealed wounds group (PWG; n = 39), which failed to achieve wound healing within 6 months. Various factors associated with wound healing, including the wound, ischemia, and foot infection (WIfI) classification, intraoperative graft flow, and pedal angiographic data, were analyzed. Regarding pedal angiographic data, in addition to the GLASS inframalleolar/pedal disease descriptor (IPD), newly formed classification system of the pedal circulation status in association with the location of wounds was included: pedal circulation status was classified into two groups as visualized arterial perfusion towards wounds (visualized perfusion) and non-visualized arterial perfusion towards wounds (non-visualized perfusion). RESULTS: Univariate analysis showed preoperative albumin (Odds ratio [OR], 0.47; 95% confidence interval [CI], 0.24-0.94; P = .027), higher WIfI clinical stage (OR, 3.88; 95% CI, 1.74-10.1; P = .0005), higher IPD (OR, 2.16; 95% CI, 1.16-4.02; P = .012), and non-visualized perfusion to wounds (OR, 5.74: 95% CI, 2.45-14.0; P < .0001) as significant for prolonged wound healing. Multivariate analysis showed higher WIfI stage (OR, 5.04; 95% CI, 1.74-14.6; P = .0029) and non-visualized perfusion to wounds (OR, 4.34; 95% CI, 1.71-11.0; P = .0021) as significant, whereas IPD was not detected as significant. Regarding blood supply to the foot, although graft flow was significantly lower in IPD-P2 than IPD-P0/P1, graft flow was similar regardless of the status of angiographic circulation to wounds, suggesting that distribution of blood supply to the wound would be more important than total amount of blood supply to the foot for wound healing. CONCLUSIONS: WIfI clinical stage and pedal circulatory environment were important factors for wound healing after bypass surgery. Pedal anatomical classification system including perfusion status would be important for decision making in CLTI treatment.

Learning curve in tibial and pedal bypass with autologous vein graft.

OBJECTIVES: The 2019 Global Vascular Guidelines recommended open bypass for patients at average risk with greater limb severity and anatomical complexity. However, the outcomes of tibial and pedal bypass (TPB) are inferior to those of above-the-knee surgical revascularization. This may be due to the technical difficulty and need for development of skills to perform TPB. However, there is a limited knowledge on the learning curve in TPB. Thus, the aim of the study is to assess this learning curve in a single-center retrospective analysis. METHODS: Cases treated with TPB with an autologous vein conduit in patients with chronic limb-threatening ischemia (CLTI) at a Japanese single center from 2009 to 2022 were analyzed retrospectively. The primary endpoint was the learning curve for TPB. RESULTS: The study included 449 TPB procedures conducted by a single main surgeon in patients with CLTI (median age, 75 years; 309 males; diabetes mellitus, 73%; end stage renal failure with hemodialysis, 44%). The operative time decreased significantly as the number of cases accumulated (p < .001). Using the cumulative sum (CUSUM) operative time, the learning curve was estimated to be phase 1 (initial learning curve) for 134 cases (1-134); phase 2 (competent period) for 179 cases (135-313); and phase 3 (mastery and challenging period) for 136 cases (314-449). The mean follow-up period was 34 ± 31 months. The 1- and 3-year limb salvage rates of 97% and 96% in phase 3 were significantly higher than those in phases 1 and 2 (p < .001, p = .029). Major adverse limb events (MALE) occurred in 117 (26%) patients, and the 1- and 3-year MALE rates of 10% and 17% in phase 3 were significantly lower than those in phases 1 and 2 (p < .001, p = .009). CONCLUSIONS: In the study, vascular surgeon required a learning curve of 134 TPB cases to Overcoming the learning curve for bypass was associated with improvement of medium-term outcomes for limb salvage and freedom from MALE.

Ectodermal origin and tissue dedifferentiation in the podocyst production by the polyps of the Asian moon jelly (Aurelia coerulea).

The histological origin of podocysts in scyphozoans has long been undetermined, with uncertainty whether they arise from mesenchymal amoebocytes or stalk and pedal disc ectoderm in polyps. Histological investigation on the pedal disc was difficult due to the settlement of polyps on hard substrates. In this study, we investigated the histological characteristics of polyps during podocyst production in Asian moon jelly (Aurelia coerulea) with utilizing those attached on thin polystyrene substrates. Fine histological features of the pedal disc became possible after the substrates were decomposed during histological processing. Our findings unequivocally demonstrate that the cell mass of podocysts originates from the ectoderm of the pedal disc and the stalk without the involvement of amoebocytes in the mesoglea. Preceding the podocyst formation, the pedal disc undergoes enlargement facilitated by the elongated stalk ectodermal cells, which attach to a substrate. Subsequently, the pedal disc ectoderm give rise to the primary podocyst cells with accumulating nutrient granules in the cytoplasm and forming the cyst capsule cooperatively with the invaginated pedal disc ectoderm. Direct transformation from the ectodermal cells to podocyst cells suggests that podocyst formation involves tissue dedifferentiation. Throughout the period of podocyst production, the gastrodermis of polyps is physically separated from the ectoderm by the mesoglea and shows no histological changes, and no amoebocytes appear in the mesoglea. These histological properties are totally different from those in other modes of asexual reproduction, which incorporate the endoderm of polyps, suggesting the developmental and evolutionary differences between these asexual reproductions and podocyst production in Scyphozoa.

Retrograde pedal access and percutaneous mechanical thrombectomy for salvage of an occluded vein bypass.

Managing occlusions in a lower extremity bypass is challenging, although several surgical methods and percutaneous devices are available for treatment. A 64-year-old man presented with subacute failure of his infrainguinal vein bypass. Because we were unable to access the bypass in an antegrade fashion, we accessed the bypass graft via retrograde pedal access. The occluded vein graft was salvaged with the Pounce percutaneous mechanical thrombectomy system (Surmodics) with the use of a 0.014-in. through and through buddy wire to maintain access in the bypass alongside the Pounce system to allow multiple passes of the nitinol baskets to retrieve thrombus.

Pedal Acceleration Time An Alternative Tool To Ankle-Brachial Index In Peripheral Arterial Disease.

INTRODUCTION: Ankle-Brachial Index (ABI) is a well-established diagnostic tool for evaluating peripheral arterial disease (PAD). Limitations in its application led to the development of alternative diagnostic methods, including Toe-Brachial Index (TBI) and Transcutaneous Pressure of Oxygen (TcPO2), yet these are not as widely available as ABI. Recently, Pedal Acceleration Time (PAT), has gained popularity as a new tool to assess PAD, requiring only an ultrasound. This study seeks to further establish the correlation between ABI and PAT, determining whether PAT can be a reliable alternative for diagnosing and assessing the severity of PAD. METHODS: ABI and PAT were measured in patients attending our consult with no history of vascular or endovascular surgery. Limbs with unmeasurable ABI were excluded. Patients were categorized into groups based on their PAD stage according to the Fontaine classification. Patient demographics, comorbidities and respective ABI and PAT were analysed. RESULTS: Sixty-nine patients (114 limbs) were included in the study. Mean age 68 ± 11.7 years, 78.3% male and 33.3% diabetic patients. Fifty-three claudicant limbs (46.5%) and 26 limbs (22.8%) with chronic limb threatening ischemia. Pearson correlation coefficient between ABI and PAT, showed a strong negative correlation (r= -0.78; p<0.01). Mean ABI and PAT for limbs in Fontaine stage I were 0.94 ± 0.17 and 82.0 ± 27.4 ms; Fontaine stage IIa 0.69 ± 0.21 and 141.3 ± 57.8 ms; Fontaine stage IIb 0.54 ± 0.14 and 173.4 ± 65.1 ms; Fontaine stage III 0.43 ± 0.15 and 216 ± 33.2 ms; Fontaine stage IV 0.49 ± 0.17 and 206.7 ± 78.1 ms, respectively. CONCLUSION: Our study suggests an inverse correlation between ABI and PAT, in accordance with the findings published in the literature, thus supporting the use of PAT as an easily reproducible and efficient alternative to ABI for evaluating the severity of PAD.

Influence of inframalleolar modifier P0/P1 on wound healing in bypass surgery vs endovascular therapy in patients with chronic limb-threatening ischemia.

OBJECTIVE: This study aimed to compare the influence of inframalleolar (IM) P0/P1 on wound healing in bypass surgery vs endovascular therapy (EVT) in patients with chronic limb-threatening ischemia (CLTI). METHODS: We retrospectively analyzed the multicenter data of patients who underwent infra-inguinal revascularization for CLTI between 2015 and 2022. IM P represents target artery crossing into foot, with intact pedal arch (P0) and absent or severely diseased pedal arch (P1). The endpoints were wound healing, limb salvage (LS), and postoperative complications. RESULTS: We analyzed 66 and 189 propensity score-matched pairs in the IM P0 and IM P1 cohorts, respectively. In the IM P0 cohort, the 1-year wound healing rates were 94.5% and 85.7% in the bypass surgery and EVT groups, respectively (P = .092), whereas those in the IM P1 cohort were 86.2% and 66.2% in the bypass surgery and EVT groups, respectively (P < .001). In the IM P0 cohort, the 2-year LS rates were 96.7% and 94.1% in the bypass surgery and EVT groups, respectively (P = .625), and those in the IM P1 cohort were 91.8% and 81.5% in the bypass surgery and EVT groups, respectively (P = .004). No significant differences were observed between the bypass surgery and EVT in terms of postoperative complication rates in either the IM P0 or P1 cohorts. CONCLUSIONS: Bypass surgery facilitated better wound healing and LS than EVT in patients with IM P1. Conversely, no differences in wound healing or LS were observed between groups in patients with IM P0. Bypass surgery should be considered a better revascularization strategy than EVT in patients with tissue loss and IM P1 disease.

Pedal medial arterial calcification influences the outcomes of isolated infra-malleolar interventions for chronic limb-threatening ischemia.

OBJECTIVE: Inframalleolar disease is present in most diabetic patients presenting with tissue loss. Inframalleolar (pedal) artery disease and pedal medial arterial calcification (pMAC) are associated with major amputation in patients with chronic limb-threatening ischemia (CLTI). This study aimed to examine the impact of pMAC on the outcomes after isolated inframalleolar (pedal artery) interventions. METHODS: A database of lower extremity endovascular intervention for patients with tissue loss between 2007 and 2022 was retrospectively queried. Patients with CLTI were selected, and those undergoing isolated inframalleolar intervention on the dorsalis pedis and medial and lateral tarsal arteries and who had foot x-rays were identified. X-rays were assessed blindly for pMAC and scored on a scale of 0 to 5. Patients with concomitant superficial femoral artery and tibial interventions were excluded. Intention to treat analysis by the patient was performed. Amputation-free survival (survival without major amputation) was evaluated. RESULTS: A total of 223 patients (51% female; 87% Hispanic; average age, 66 years; 323 vessels) underwent isolated infra-malleolar intervention for tissue loss. All patients had diabetes, 96% had hypertension, 79% had hyperlipidemia, and 63% had chronic renal insufficiency (55% of these were on hemodialysis). Most of the patients had Wound, Ischemia, and foot Infection (WIfI) stage 3 disease and had various stages of pMAC: severe (score = 5) in 48%, moderate (score = 2-4) in 31%, and mild (score = 0-1) in 21% of the patients. Technical success was 94%, with a median of one vessel treated per patient. All failures were in severe pMAC. Overall, major adverse cardiovascular events was 0.9% at 90 days after the procedure. Following the intervention, most patients underwent a planned forefoot amputation (single digit, multiple digits, ray amputation, or trans-metatarsal amputation). WIfI ischemic grade was improved by 51%. Wound healing at 3 months was 69%. Those not healing underwent below-knee amputations. The overall 5-year amputation-free survival rate was 35% ± 9%. The severity of pMAC was associated with decreased AFS. CONCLUSIONS: Increasing severity of pMAC influences the technical and long-term outcomes of infra-malleolar intervention in diabetes. Severe pMAC is associated with amputation and should be considered as a variable in the shared decision-making of diabetic patients with CLTI.

Pedal medial arterial calcification in diabetic foot ulcers: A significant risk factor of amputation and mortality.

AIMS: Pedal medial arterial calcification (MAC) is frequently observed in individuals with diabetic foot ulcers (DFUs). However, the impact of pedal MAC on individuals with DFUs remains uncertain. The main aim of this study was to evaluate the association between pedal MAC with amputation and mortality outcomes. METHODS: A prospective, observational cohort study was conducted at West China Hospital from January 2012 to December 2021. Logistic regression analyses, Kaplan-Meier survival method, and Cox proportional hazards models were employed to evaluate the relationship between pedal MAC and amputation as well as mortality. RESULTS: A total of 979 patients were enrolled in the study. Peripheral artery disease (PAD) was observed in 53% of patients with DFUs, and pedal MAC was found in 8%. Over a median follow-up of 46 (23-72) months, foot amputation was performed on 190 patients, and mortality occurred in 246 patients. Pedal MAC showed a significant association with amputation both in unadjusted analysis (odds ratio [OR] = 2.98, 95% confidence interval [CI] = 1.86-4.76, p < .001) and after adjusting sex, age, albumin levels, hemoglobin levels, and diabetic retinopathy status (OR 2.29, 95% CI 1.33-3.93, p = .003). The risk of amputation was found to be twofold higher in individuals with PAD and pedal MAC compared to those with PAD alone (OR 2.05, 95% CI 1.10-3.82, p = .024). Furthermore, the presence of pedal MAC was significantly associated with an increased risk of mortality (p = .005), particularly among individuals with DFUs but without PAD (HR 4.26, 95% CI 1.90-9.52, p < .001), rather than in individuals presenting with both DFUs and PAD. CONCLUSION: The presence of pedal MAC is significantly associated with both amputation and mortality in individuals with DFUs. Moreover, pedal MAC could provide additional value to predict amputation other than PAD.

Effects of repetition of a car-driving pedal maneuver and neural output in older adults.

Understanding the ability of older adults to control pedal position angle and investigating whether this ability can be enhanced through practice may contribute to the prevention of traffic accidents. This study aimed to investigate repetitive effects on variability of the pedal position and neural drive during car-pedal operation in older adults. Thirteen older and 11 young adults performed 105 (21 sets × 5 repetitions) pedal angle control tasks with plantar flexor contraction. High-density surface electromyograms were recorded of triceps surae muscles. A cumulative spike train as a neural drive was calculated using continuously active motor unit activities. The coefficient of variation of the angle was higher in older (1.47 ± 1.06 %) than young (0.41 ± 0.21 %) adults in the first sets, and improved to 0.67 ± 0.51 % in the final sets in older adults only. There was no significant difference in neural drive variability between older and young adults. Our results suggest that repetition improves angular steadiness in older adults. However, this effect could not be explained by neural output which is estimated from lower threshold motor units that are continuously active.

Peripheral oedema as an adverse effect of treatment of secondary progressive multiple sclerosis with siponimod: A case series.

Siponimod is a sphingosine 1-phosphate receptor (S1P) modulator used to treat secondary progressive multiple sclerosis (SPMS). We report 3 SPMS patients treated with siponimod who developed new or worsening peripheral oedema soon after commencing treatment. In one case, peripheral oedema resulted in immobility. Siponimod-related peripheral oedema deserves wider recognition due to the potential for morbidity and over-investigation. Clinicians should assess for pre-existing oedema and coexisting conditions that may predispose to developing peripheral oedema prior to commencing siponimod.

Tips and Tricks for Simple and Complex Below-the-Ankle Punctures.

CLINICAL IMPACT: When the standard endovascular crossing maneuvers have failed during CLTI recanalization procedures and the distal below-the-knee or proximal below-the-ankle retrograde access is not possible due to chronic occlusion of the vessels, mastering the more distal and complex retrograde BTA punctures may be advantageous.There are scanty reports regarding the retrograde puncture of the mid and forefoot vessels. The aim of this article is to review different tips and tricks related to these techniques to help operators to apply them in specific scenarios to eventually improve procedural success rate.

Effects of releasing ankle joint during electrically evoked cycling in persons with motor complete spinal cord injury.

Literature has shown that simulated power production during conventional functional electrical stimulation (FES) cycling was improved by 14% by releasing the ankle joint from a fixed ankle setup and with the stimulation of the tibialis anterior and triceps surae. This study aims to investigate the effect of releasing the ankle joint on the pedal power production during FES cycling in persons with spinal cord injury (SCI). Seven persons with motor complete SCI participated in this study. All participants performed 1 min of fixed-ankle and 1 min of free-ankle FES cycling with two stimulation modes. In mode 1 participants performed FES-evoked cycling with the stimulation of quadriceps and hamstring muscles only (QH stimulation), while Mode 2 had stimulation of quadriceps, hamstring, tibialis anterior, and triceps surae muscles (QHT stimulation). The order of each trial was randomized in each participant. Free-ankle FES cycling offered greater ankle plantar- and dorsiflexion movement at specific slices of 20° crank angle intervals compared to fixed-ankle. There were significant differences in the mean and peak normalized pedal power outputs (POs) [F(1,500) = 14.03, p < 0.01 and F(1,500) = 7.111, p = 0.008, respectively] between fixed- and free-ankle QH stimulation, and fixed- and free-ankle QHT stimulation. Fixed-ankle QHT stimulation elevated the peak normalized pedal PO by 14.5% more than free-ankle QH stimulation. Releasing the ankle joint while providing no stimulation to the triceps surae and tibialis anterior reduces power output. The findings of this study suggest that QHT stimulation is necessary during free-ankle FES cycling to maintain power production as fixed-ankle.

Exoscopic resection of giant olfactory groove meningioma.

Olfactory groove meningiomas represent 8%-13% of all intracranial meningiomas. Gross-total resection for large (4-6 cm) and giant (> 6 cm) cases remains challenging due to their relationship with critical neurovascular structures and extensive frontal lobe edema. A variety of transcranial and endoscopic approaches have been described. This 2D operative video shows the use of a digital 3D exoscope in the removal of a giant olfactory groove meningioma through a lateral supraorbital approach in a 57-year-old woman with visual impairment and apathy. The exoscope provides a very good angulated view of the subfrontal area on both sides of the anterior cranial fossa even through a small craniotomy. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23125.

Active control of static pedal force direction decreases maximum isometric force output.

Perfect mechanical force effectiveness in cycling would be achieved if the forces applied to the pedal were perpendicular to the crank throughout the full crank cycle. However, empirical observations show that resultant pedal forces display substantial radial components in recreational and even highly-trained elite cyclists. Therefore, we hypothesized that attempting to maximize mechanical effectiveness during the entire downstroke of the pedal cycle must be associated with a penalty that outweighs the benefits of perfect effectiveness. Twenty recreational cyclists performed maximum isometric voluntary contractions at five static crank positions in the downstroke phase of cycling for two testing conditions: (i) a non-constrained (NC) condition, where athletes were asked to produce the maximum force possible on the pedal without consideration of the force direction and (ii) a constrained (C) condition, with the instruction to produce maximal pedal forces perpendicular to the crank. Resultant force and effective force (force perpendicular to the crank in the NC conditions) were compared to the force in the C condition that was, by definition, perpendicular to the crank. Maximum effective force in the NC condition was greater (mean = 50 %, range = 38-69 %) than for the C condition across all crank positions. Applying forces perpendicular to the crank in the downstroke of the pedal cycle resulted in severe reductions in force magnitude, suggesting that coaches and athletes should not attempt to change cycling technique towards perfect force effectiveness.

Molecular Characterization, Expression and In Situ Hybridization Analysis of a Pedal Peptide/Orcokinin-type Neuropeptide in Cuttlefish Sepiella japonica.

BACKGROUND: Neuropeptide pedal peptide (PP) and orcokinin (OK), which are structurally related active peptides, have been widely discovered in invertebrates and constitute the PP/OK neuropeptide family. They have complex structures and play myriad roles in physiological processes. To date, there have been no related reports of PP/OK-type neuropeptide in cephalopods, which possess a highly differentiated multi-lobular brain. METHODS: Rapid Amplification of cDNA Ends (RACE) was employed to obtain the open reading frame (ORF) of PP/OK-type neuropeptide in Sepiella japonica (termed as Sj-PP/OK). Various software were used for sequence analysis. Semi-quantitative PCR was applied to analyze the tissue distribution profile, quantitative real-time PCR (qRT-PCR) was used to study spatio-temporal expression throughout the entire growth and development period, and in situ hybridization (ISH) was employed to observe the tissue location of Sj-PP/OK. RESULTS: in the present study, we identified the ORF of Sj-PP/OK. The putative precursor of Sj-PP/ OK encodes 22 mature peptides, of which only tridecapeptides could undergo post-translationally amidated at C-terminus. Each of these tridecapeptides possesses the most conserved and frequent N-terminus Asp-Ser-Ile (DSI). Sequence analysis revealed that Sj-PP/OK shared comparatively low identity with other invertebrates PP or OK. The tissue distribution profile showed differences in the expression level of Sj-PP/OK between male and female. qRT-PCR data demonstrated that Sj-PP/OK was widely distributed in various tissues, with its expression level increasing continuously in the brain, optic lobe, liver, and nidamental gland throughout the entire growth and development stages until gonad maturation. ISH detected that Sj-PP/OK positive signals existed in almost all regions of the optic lobe except the plexiform zone, the outer edge of all functional lobes in the brain, epithelial cells and the outer membrane layer of the accessory nidamental gland. These findings suggest that Sj-PP/OK might play a role in the regulation of reproduction, such as vitellogenin synthesis, restoration, and ova encapsulation. CONCLUSION: The study indicated that Sj-PP/OK may be involved in the neuroendocrine regulation in cephalopods, providing primary theoretical basis for further studies of its regulation role in reproduction.