Comprehensive Analysis of Scientific Output in Hip and Knee Arthroscopy.

PURPOSE OF THE STUDY A global bibliometric comparison of the level of scientific interest and output in the two research areas hip and knee arthroscopy (H-ASC and K-ASC) was carried out. In addition, the different degrees of publication activity in the countries and institutes performing this research were investigated. MATERIAL AND METHODS Publications from 1945-2020 listed in the Web of Science Core Collection were included in the study. Using the web application Science Performance Evaluation (SciPE), quantitative and qualitative aspects were evaluated. Subsequently, the date of publication, author information, and other metadata were analysed. RESULTS Since 1945, 3,924 studies have been published on K-ASC and 2,163 on H-ASC. The majority of the publications which have appeared since 2016 dealt with the topic of H-ASC (H-ASC: 241.2 publications/year; K-ASC: 217.4 publications/year). The USA published the most on both topics (H-ASC: 1,123 publications; K-ASC: 1,078 publications). More countries and institutes participated in K-ASC (3,008 institutes, 82 countries) than in H-ASC (103 institutes, 57 countries). The ten institutes with the most publications accounted for 36.71% and 12.34% of all publications on H-ASC and K-ASC, respectively. H-ASC received 78.12% of its funding from private sponsors while K-ASC was supported mainly by governmental/nonprofit sponsors (70.92%). CONCLUSIONS This study provides the first scientific comparison between H-ASC and K-ASC. Measured by qualitative and quantitative aspects, K-ASC was the most flourishing research area overall. In the last ten to five years, interest has shifted towards HASC with an increasing number of publications and a higher rate of citations. Key words: knee arthroscopy, hip arthroscopy, bibliometric comparison.

Editor's Choice - Reconstruction of the femoro-ilio-caval outflow by percutaneous and hybrid interventions in symptomatic deep venous obstruction.

OBJECTIVE/BACKGROUND: Deep venous obstruction is relatively prevalent in patients with chronic venous disease. Endovascular treatments and hybrid interventions can be used to relieve venous outflow obstructions. This paper assesses mid-term clinical outcomes and patency rates in a large cohort after percutaneous and hybrid interventions. METHODS: This was a prospectively analysed cohort study. Patients with symptomatic deep venous obstruction who presented at a tertiary referral hospital were divided into three groups: patients who underwent percutaneous stenting for non-thrombotic iliac vein compression syndrome (IVCS group); patients with post-thrombotic syndrome (PTS) treated by percutaneous stent placement (P-PTS group); and PTS patients with obstruction involving the veins below the saphenofemoral junction in which a hybrid procedure was performed, combining stenting with open surgical disobliteration (H-PTS group). Patency rates, complications, and clinical outcomes were analysed. RESULTS: A total of 425 lower extremities in 369 patients were treated. At 60 months, primary patency, assisted primary patency, and secondary patency rates were 90%, 100%, and 100% for IVCS, and 64%, 81%, and 89% for the P-PTS group, respectively. The H-PTS group, showed patency rates of 37%, 62%, and 72%, respectively, at 36 months. Venous claudication subsided in 90%, 82%, and 83%, respectively. At the 24 month follow-up, mean Venous Clinical Severity Score decreased for all patients and improvement in Villalta score was seen in post-thrombotic patients. The number of complications was related to the extent of deep venous obstruction in which patients in the H-PTS group showed the highest complication rates (81%) and re-interventions (59%). CONCLUSION: Percutaneous stent placement to treat non-thrombotic iliac vein lesions, and post-thrombotic ilio-femoral obstructions are safe, effective, and showed patency rates comparable with previous research. Patients with advanced disease needing a hybrid procedure showed a lower patency rate and more complications. However, when successful, the clinical outcome was favourable at mid-term follow-up and the procedure may be offered to selected patients.

Endophlebectomy of the common femoral vein and arteriovenous fistula creation as adjuncts to venous stenting for post-thrombotic syndrome.

BACKGROUND: Good results have been reported for angioplasty and stenting of post-thrombotic lesions of the iliac and proximal femoral veins. If lesions at the origin of the superficial femoral and profunda veins are stented, the intraluminal synechiae can be pushed against the orifices of inflow vessels, potentially decreasing stent inflow. Surgical disobliteration of the common femoral vein (endophlebectomy) has been suggested to mitigate this problem. Because of a temporary increase in thrombogenicity, this procedure may be accompanied by arteriovenous fistula creation. METHODS: Data on consecutive patients treated by hybrid venous reconstruction, between December 2010 and May 2015, were analysed. Standard recording consisted of clinical scoring systems (including Villalta scale) and imaging. Patency was assessed with duplex ultrasonography. RESULTS: Seventy-six legs (70 patients) were included. Median follow-up was 379 (range 73-1508) days. Primary, assisted primary and secondary patency rates at 12 months were 51, 70 and 83 per cent respectively. Sixty per cent of loss of primary patency (24 of 40 legs) was related to common femoral vein stenosis, and the rest to rethrombosis. Other complications included wound infection (29 per cent) and lymphatic leak (39 per cent). The Villalta score had decreased by a median of 7 points at 1-year follow-up. CONCLUSION: The combination of venous stenting, endophlebectomy and arteriovenous fistula creation for patients with extensive post-thrombotic vein damage and severe post-thrombotic syndrome is feasible.

Interventional treatment of postthrombotic syndrome.

BACKGROUND: Postthrombotic syndrome (PTS) is the development of symptoms and signs of chronic venous insufficiency following deep vein thrombosis (DVT) and has a significant negative effect on the quality of life. The current understanding is that the clinical manifestation of PTS is related more to venous obstruction than it is to venous reflux. The use of interventional techniques for the treatment of venous obstruction and/or venous occlusion has rapidly increased in recent years. OBJECTIVE: This article summarizes the current concept of endovenous and hybrid interventions and presents the optimized treatment of choice in patients with chronic symptomatic venous obstruction. METHODS: We performed a systematic literature search in the Medline database to identify relevant studies on the treatment of patients with PTS. RESULTS: A meta-analysis of the relevant studies showed that this minimally invasive procedure is an effective treatment option with low morbidity and no mortality. Use of the newly developed dedicated venous stents showed promising results with good mid-term patency rates and a significant decrease in related symptoms. CONCLUSION: Interventional therapy for the treatment of symptomatic chronic venous obstruction has become the method of choice in recent years. More studies are needed to evaluate the long-term success rate of dedicated venous stents.

Intravenous pressure changes in patients with postthrombotic deep venous obstruction: results using a treadmill stress test.

UNLABELLED: Essentials Little is known about the hemodynamic consequences of deep venous obstructive disease. We investigated pressure changes in 22 patients with unilateral postthrombotic obstruction. Common femoral vein pressure significantly increased after walking, compared to control limbs. Common femoral vein hypertension could explain the debilitating effect of venous claudication. Click to hear Dr Ten Cate's perspective on postthrombotic syndrome SUMMARY: Background Little is known about the hemodynamic consequences of deep venous obstructive disease. Objectives The aim of this study was to investigate the hemodynamic effect of postthrombotic obstruction of the iliofemoral veins and to determine what pressure parameters differentiate best between limbs with post-thrombotic obstructive disease of the iliofemoral veins and those without obstruction. Methods Twenty-two participants with unilateral obstruction of the iliac and common femoral veins underwent a standardized treadmill test with simultaneous bilateral invasive pressure measurements in the common femoral vein and dorsal foot vein. Results Mean age was 42.8 ± 11.9 years and 86.4% of participants were female. Postthrombotic limbs showed a mean common femoral vein (CFV) pressure increase of 28.1 ± 21.0 mmHg after walking, compared with 2.1 ± 6.2 mmHg in control limbs (26.0 mmHg difference; 95% confidence interval [CI], 17.1-34.9). Less difference was observed in the dorsal foot vein (net drop of 36.8 ± 22.7 mmHg in affected limbs vs. 48.7 ± 23.1 mmHg in non-affected limbs, 11.9 mmHg difference; 95% CI, -1.3 to 25.0). Change in CFV pressure after walking yielded the best discrimination between affected and non-affected limbs (area under the receiver operated characteristic curve of 0.94 [95% CI, 0.85-1.00], compared with 0.57 [95% CI, 0.37-0.76] in the dorsal foot vein, P < 0.001). Conclusions Common femoral vein pressure significantly increases during ambulation in patients with iliofemoral postthrombotic obstruction, which could explain the debilitating effects of venous claudication. This is an indication that patients with an iliofemoral obstruction may benefit from further treatment that resolves the deep vein obstruction. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/show/NCT01846780.

Short-Term Clinical Experience with a Dedicated Venous Nitinol Stent: Initial Results with the Sinus-Venous Stent.

OBJECTIVE: Deep venous stenting has become the primary treatment option for chronic venous obstructive disease, both for iliac vein compression and post-thrombotic venous lesions. Until recently, only stents aimed at arterial pathology were used, because no dedicated venous stents were available. However, three such stents have now become available. These venous stents are characterized by increased length, diameter, flexibility, and radial force. This study reports an early experience with one of these devices; the sinus Venous stent (OptiMed GmbH, Ettlingen, Germany). METHODS: Between March 2012 and July 2014, 75 patients were treated with the sinus Venous stent: 35 cases of iliac vein compression syndrome and 40 cases of unilateral chronic obstruction in post-thrombotic syndrome (PTS). Diagnosis of relevant obstruction was made using clinical evaluation, duplex ultrasound, and magnetic resonance venography. Patency during follow up was assessed with duplex ultrasound. Clinical improvement was assessed by VCSS, Villalta score, rate of ulcer healing, and improvement of venous claudication. RESULTS: The cumulative patency rates at 3, 6, and 12 months were 99%, 96%, and 92%, respectively. The cumulative assisted primary patency rates were 99% at 3, 6, and 12 months. The cumulative secondary patency rate at 12 months was 100%. Differences exist in patency rate between the subgroups of non-thrombotic and post-thrombotic, with the first showing no re-occlusions. All re-thromboses in the PTS group were treated by ancillary treatment modalities. VCSS and Villalta score decreased significantly after stenting, as did venous claudication. Morbidity was low without clinically relevant pulmonary embolism, and mortality was nil. Although two out of seven ulcers healed temporarily, no ulcer remained healed at 12 months follow up. CONCLUSION: Short-term clinical results using the sinus Venous stent are excellent, with significant symptom reduction, low morbidity rates, and no mortality. Loss of stent patency is seen less often compared with arterial stents described in the literature.

Hemodynamic significance of collateral blood flow in chronic venous obstruction.

INTRODUCTION: Complaints related to the post-thrombotic syndrome do not always correlate well with the extent of post-thrombotic changes on diagnostic imaging. One explanation might be a difference in development of collateral blood flow. The aim of this study is to investigate the hemodynamic effect of collateralisation in deep venous obstruction. METHODOLOGY: Resting intravenous pressure of the common femoral vein was measured bilaterally in the supine position of patients with unilateral iliofemoral post-thrombotic obstruction. In addition, pressure in control limbs was also measured in the common femoral vein after sudden balloon occlusion in the external iliac vein. RESULTS: Fourteen patients (median age 42 years, 12 female) were tested. In eleven limbs post-thrombotic disease extended below the femoral confluence. Median common femoral vein pressure was 17.0 mmHg in diseased limbs compared to 12.8 mmHg in controls (p = 0.001) and 23.5 mmHg in controls after sudden balloon occlusion (p = 0.009). Results remained significant after correcting for non-occlusive post-thrombotic disease. CONCLUSION: This study shows that common femoral vein pressure is increased in post-thrombotic iliofemoral deep venous obstruction, though not as much as after sudden balloon occlusion. The latter difference could explain the importance of collateralisation in deep venous obstructive disease and the discrepancy between complaints and anatomical changes; notwithstanding, the presence of collaterals does not eliminate the need for treatment.

Arteriovenous fistula geometry in hybrid recanalisation of post-thrombotic venous obstruction.

INTRODUCTION: Post-thrombotic obstruction can be adequately treated by percutaneous transluminal angioplasty and stenting. When post-thrombotic trabeculations extend below the femoral confluence, proper inflow can be facilitated by endophlebectomy and creation of an arteriovenous fistula. The aim of this study was to investigate whether it is more favourable to place the arteriovenous fistula at the cranial or caudal end of the endophlebectomy to prevent stenosis or occlusion. METHODOLOGY: We retrospectively analysed the clinical data of all patients who underwent a hybrid procedure in our two centres. Demographics, interventional details and post-operative imaging were collected. RESULTS: Data on 42 limbs with cranially and 23 limbs with caudally placed arteriovenous fistulas were collected. Post-thrombotic disease of the profunda femoral vein alone or in combination with the femoral vein was observed more often in the cranial group. The caudal group more often received a smaller sized and straight polytetrafluoroethylene fistula, while the cranial group comprised a significantly higher amount of stented segments. Logistic regression showed that only reduced femoral inflow (hazard ratio 2.934 (95%CI, 1.148-7.494)) was a significant predictor of stent stenosis and/or occlusion. Logistic regression for risk of occlusion showed a significant influence of stent-related complications (hazard ratio 4.691 (95%CI, 1.205-18.260)) and a tendency towards influence of arteriovenous fistula geometry in favour of the cranially placed fistula. CONCLUSION: Placement of the arteriovenous fistula in the cranial part of the endophlebectomy during hybrid recanalisation may result in a more favourable outcome, yet this tendency was not statistically significant. Moreover, femoral inflow is pivotal in maintaining patency and should thus be adequately assessed pre-operatively.

Diagnostic imaging of pelvic congestive syndrome.

Many female patients are affected by chronic pelvic pain and a significant number of referrals to the gynecology department result in a clinical suspicion of pelvic congestion syndrome. Additionally, patients referred to the vascular surgery department for venous disease can also present with complaints of a persistent dull lower abdominal pain in addition to typically distributed leg varicosities (that extend from the leg through the pelvic floor) which should be evaluated for the presence of pelvic congestion syndrome. In this article, we focus on imaging pelvic vein insufficiency and related (extending) varicosities: how should we evaluate the pelvic veins, what are the signs to look for, and what are the currently established criteria for (pre-interventional) imaging.

Quality-of-life in interventionally treated patients with post-thrombotic syndrome.

INTRODUCTION: New developments in the treatment of complex deep venous disease have become available in the last decade. Besides analysing patencies as a surrogate outcome for these treatments we analysed the Quality-of-Life (QoL) changes for successful and failed deep venous treatments. MATERIALS AND METHODS: Patients with proven venous occlusive disease, referred to our department of Venous Surgery at the Maastricht University Medical Centre, were included. After inclusion patients were treated by percutaneous transluminal angioplasty and stenting and when indicated endophlebectomy with an arteriovenous fistula. QoL was assessed with the disease specific VEINES-QOL/Sym and the generic Short-Form (SF)-36 questionnaires preoperatively at baseline and post-operatively after 3, 12 and 24 months. RESULTS: One hundred fifty-three interventions were analysed, showing a primary, assisted primary and secondary patency of respectively 65%, 78% and 89% at 24 months. The VEINES-QOL and Sym scores improved at 3, 12 and 24 months. The overall improvement at 24 months is 22.7 for QoL and 18.18 for Sym with respective p values of 0.013 and 0.016. The improvement of the VEINES-QOL and Sym scores after a successful (patent) treatment remained highly significant (QoL: p < 0.001, Sym: p = 0.004). Also the generic QoL (Short-Form 36v2) shows significant improvement after 12 months for physical functioning (p = 0.004) and role physical (p = 0.004) scales. CONCLUSIONS: The overall patencies of interventions for deep venous pathology are exceptionally good after two years. Concomitantly the VEINES-Sym and VEINES-QOL scores improve significantly for 3, 12, and 24 months when compared to the baseline (T0) after treatment. Successful interventions showed, as expected, a significant greater QoL improvement between T0 and T3, T12, T24 for both VEINES-QOL and VEINES-Sym scores when compared to the failed interventions. The one-year linear improvement of two SF-36 scales (PF and RP) is also significant.

Venous in-stent thrombosis treated by ultrasound accelerated catheter directed thrombolysis.

OBJECTIVE/BACKGROUND: Stent placement in the venous system is an increasingly used treatment modality in chronic venous obstruction and as additional treatment after thrombolytic therapy in ilio-femoral deep vein thrombosis (DVT). Experience in treating in-stent thrombosis with ultrasound accelerated catheter directed thrombolysis (UACDT) is reported. METHODS: A retrospective analysis of patients treated for venous stent occlusion, after percutaneous transluminal angioplasty (PTA) and stent placement for either chronic venous occlusive disease or persistent vein compression in patients with acute DVT was performed. Duration of occlusion and suspected clot age were assessed using patient complaints and typical findings on duplex ultrasonography (DUS). DUS and venography were used to assess patency and to determine the cause of re-occlusion. Acute treatment of occlusion was by UACDT. Additional procedures included PTA, stent placement, and creation of an arteriovenous (AV) fistula. RESULTS: Eighteen patients (median age 43 years; 67% male), treated for occluded stent tracts with UACDT between January 2009 and July 2014, were identified. Indications for initial stenting were treatment of chronic venous obstructive disease (12 patients) and treatment of underlying obstruction after initial thrombolysis in acute DVT (six patients). Technical success was achieved in 11/18 (61%) patients. Primary patency in 8/11 patients was 73% at last follow up (median follow up 14 months [range 0-41 months]). Additional treatments after successful lysis were re-stenting (seven patients) and creation of an AV fistula (six patients). CONCLUSION: Treatment with UACDT of recently occluded stent tracts is feasible and effective. Recanalization of the stent tract can be achieved in most cases. Additional interventions were frequently used after successful UACDT treatment. Suboptimal stent positioning caused the majority of the stent occlusions.

Indications for endophlebectomy and/or arteriovenous fistula after stenting.

Endovenous recanalization with percutaneous transluminal angioplasty and stenting in post-thrombotic syndrome patients with iliocaval obstruction is a treatment modality quickly gaining popularity. Studies show good patency and clinical success rates. If the obstruction extends distally, below the inguinal ligament, stenting remains controversial. Without adequate inflow, the patency of stented iliocaval segments drops dramatically. This suggests that treatment of diseased common femoral, femoral and profunda femoral veins is required to ensure adequate inflow. Endophlebectomy, the removal of synechiae and septae from the common femoral vein, is a viable option in these cases. Another option, which can be done concurrently with the endophlebectomy, is the creation of an arteriovenous fistula. Selecting patients for these interventions however remains difficult, as precise preoperative prediction of inflow into the stented segments is difficult. In this paper we describe our experience in using duplex ultrasonography, magnetic resonance venography and conventional venography to assess the patency of the inflow trajectory. We believe this approach is essential in dealing with cases of complex post-thrombotic disease extending below the inguinal ligament. There is a great need to establish criteria to accurately assess pre- and postinterventional flow through treated vein segments.

Incidence and risk factors of the post-thrombotic syndrome.

Annually 1-2 in every 1000 adults will develop a deep venous thrombosis of the lower extremity. A third to half of these patients will develop the post-thrombotic syndrome (PTS). However, predicting which patients will develop the PTS remains elusive. Ipsilateral thrombosis recurrence seems to be the most important risk factor. Moreover, residual venous occlusion and valvular reflux seem to predict PTS incidence to some degree. Laboratory parameters, including d-dimers and inflammatory markers, have shown promise in predicting development of the PTS in patients and are currently under investigation. Creating a model based on all combined risk factors and patient characteristics might aid in risk stratification in individual patients.

Memory impairment in schizophrenia: a study using event-related potentials in implicit and explicit tasks.

Although memory impairment is recognized as a major fact of schizophrenia, only a few studies have investigated memory impairments with specifically designed event-related potential (ERP) protocols. In this study, ERPs were recorded from 15 schizophrenia patients and 15 matched control subjects during implicit and explicit memory tasks for unfamiliar faces. The results showed that patients have a reduced modulation of an N400-like component in both the implicit and explicit tasks that suggests a deficient integration of incoming information with personal knowledge. Patients also displayed an enhanced frontally distributed activity in the explicit task that may represent an impairment in the integration of intrinsic contextual information, a disturbance in the ability to inhibit proactive interference or a combination of both processes. Finally, the modulation of the late positive component did not differ from that in control subjects in both implicit and explicit tasks, suggesting that the impairment in mnemonic binding processes suggested in schizophrenia is more qualitative, i.e. incomplete or inappropriate, due to the anomalies in antecedent processes. The correlations observed between impairments of ERP modulation and symptoms further support these interpretations.

Neuropsychological impairments in the syndromes of schizophrenia: a comparison between different dimensional models.

This study investigates the associations between the different symptom dimensions of schizophrenia and neuropsychological performances. Globally, the results replicate previously described associations. The "negative" dimension correlates with impaired sustained attention and working memory, thus suggestive of dorsolateral frontal cortex dysfunction. "Disorganization" correlates with the ability to inhibit proactive interference. thus with ventromedial frontal dysfunction. The results also add support to the view that the "psychotic" dimension described in three-dimension models includes in fact two distinct dimensions, (1) "hallucinations," here associated to episodic memory measures, and (2) "delusions", here associated to visuospatial attention, thus suggestive of mediotemporal and posterior neocortical dysfunction, respectively.