The Comparative Analysis of Antegrade Versus Retrograde Approach for a Failed Porous Tantalum Rod Removal During Conversion to Total Hip Arthroplasty.

BACKGROUND The failure of porous tantalum rods applied to patients with osteonecrosis of the femoral head (ONFH) has been increasingly reported during the last few years. Very few studies have reported methods for implant removal. This study aimed at comparing 2 procedures used for the removal of a failed tantalum rod during conversion to total hip arthroplasty (THA). MATERIAL AND METHODS A total of 65 patients (65 hips), who underwent THA after failed implantation of a tantalum rod between June 2007 and December 2016, were retrospectively evaluated. These patients were classified into 2 groups depending on whether the antegrade approach (removal of the tantalum rod from the tip to the butt at the lateral femoral cortex, n=27) or retrograde approach (removal of the tantalum rod from the butt at the lateral femoral cortex to the proximal tip, n=38) was used for rod extraction. These 2 groups were compared for incision length, operation time, blood loss, fracture, tantalum debris, Harris hip scores, and the presence of osteolysis and/or radiolucency. RESULTS These 2 groups did not present any significant differences in terms of Harris hip score and incision length. However, the operation time (P=0.000), blood loss (P=0.000), amount of tantalum debris (P=0.000), and presence of radiolucency (P=0.046) were greater for the retrograde approach than for the antegrade approach. CONCLUSIONS The risk of conversion to THA following failed tantalum rod implantation is high. In such cases, the antegrade procedure was found to be a simple and efficient method for removing the trabecular metal rod with the use of a trephine.

Outcomes of Onyx® Embolization of Type II Endoleaks After Endovascular Repair of Abdominal Aortic Aneurysms.

BACKGROUND: Type II endoleaks (T2ELs) are common following endovascular repair of abdominal aortic aneurysms (EVAR). Embolization with ethylene vinyl alcohol copolymer (Onyx) may present an effective treatment alternative for T2ELs. Due to limited data supporting its use, we sought to analyze outcomes of Onyx embolization for T2ELs. METHODS: Retrospective review of consecutive patients treated for T2ELs utilizing Onyx embolization agent from 2009-2018. All pre- and post-Onyx intervention CT scans were analyzed for diameter and volume changes with 3D reconstruction software. The primary outcomes were change in maximum AAA diameter and volume. Secondary outcomes included additional interventions, rupture, and mortality. A subset analysis was performed with patients with isolated T2ELs (no other types of endoleaks present). RESULTS: We identified 85 patients (73 males, mean age 77.6 ± 7.6 years) who underwent 112 Onyx interventions. Average time to first Onyx intervention after index EVAR was 3.3 ± 2.6 years and average sac growth was 6.3 ± 6.7 mm. Patients underwent mean 1.3 Onyx interventions using a mean of 4.9 ± 4.7 ml for treatment. Three complications occurred (Onyx extravasation, colon ischemia, and access site hematoma). Mean follow-up was 2.5 ± 2.1 years after initial Onyx treatment. At the most recent follow-up, sac diameter stabilization was seen in 47% and reduction >5 mm was seen in 19%. Sac growth of >5 mm was seen in 34% of patients following the first Onyx intervention. In our subset of isolated T2EL, 72% had sac stabilization or reduction >5 mm. Four patients experienced a ruptured aneurysm (3 had active type 1 endoleaks). Rupture-free survival was 95% at 5 years, and overall survival was 54% at 5 years. Notably, increasing Onyx interventions were not associated with sac stabilization or reduction (OR 0.6, P = 0.1). On multivariable analysis, AAA sac diameter stabilization or reduction was independently associated with BMI >30 kg/m2 (OR 4.2, P = 0.01) and having only 1 Onyx intervention (OR 3.8, P = 0.02). CONCLUSIONS: Onyx for embolization of T2ELs resulted in AAA sac diameter stabilization or reduction in 66% of patients, and up to 72% in isolated T2ELs. Further, increasing Onyx interventions were not associated with either aneurysm sac stabilization or reduction. Given its similar outcomes to other embolization strategies in the literature, Onyx embolization for management of T2ELs needs to be judiciously considered, particularly for T2ELs persisting after an initial Onyx embolization intervention.

Vagal Nerve Palsy After Transarterial Embolization of Transverse-Sigmoid Dural Arteriovenous Fistula Using Onyx.

OBJECTIVE: We report a case of a 70-year-old man who developed a transverse-sigmoid dural arteriovenous fistula (TS-DAVF) that was successfully treated by transarterial embolization (TAE) with Onyx. CASE PRESENTATION: The patient presented with sudden and progressive disturbance of consciousness and left hemiparesis. Magnetic resonance imaging (MRI) revealed venous infarction and hemorrhagic changes with brain swelling in the right parietal lobe. Angiography revealed a right TS-DAVF and multiple occlusions with retrograde leptomeningeal venous drainage into the cortical veins. The TS-DAVF was graded as Borden type III and Cognard type IIa+b. Because of its progressive clinical nature and wide distribution of DAVF in the occluded sinus wall, he underwent emergent TAE with liquid embolic materials including n-butyl cyanoacrylate and Onyx under informed consent by his family. Complete obliteration of the TS-DAVF was achieved, leading to a marked amelioration of symptoms, and MRI after treatment confirmed a decrease in the brain swelling. However, he suffered transient dysphagia due to right vagal nerve palsy caused by occlusion of vasa nervorum of ascending pharyngeal artery. He returned home 5 months later with a modified Rankin Scale of 1. CONCLUSIONS: TAE with Onyx appears to be effective for aggressive TS-DAVF with a widely distributed shunt. However, the blood supply to the cranial nerves and potentially dangerous anastomoses between the external-internal carotid artery and vertebral artery should be taken into account to avoid serious complications.

Septal reduction therapy using nonalcohol agent in hypertrophic obstructive cardiomyopathy: Single center experience.

AIMS: Percutaneous septal reduction therapy by either alcohol or nonalcohol agents is an alternative approach to surgery in drug-refractory symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM). Nonalcohol agents have some advantages and disadvantages over alcohol during the procedure. Nowadays, a novel non-alcohol agent, named as Ethylene-vinyl alcohol (EVOH) copolymer (Onyx® and Squid® ), is used during septal ablation. Thus, in this study, we aimed to evaluate both acute and long-term efficacy and safety profile of EVOH during septal ablation in HOCM. METHODS AND RESULTS: A total of 25 patients (52% female; mean age: 55.8 ± 17.1 years) with symptomatic HOCM were enrolled in the study. All subjects underwent clinical and laboratory assessment before and after the procedure. Peak left ventricular outflow tract (LVOT) gradient was significantly reduced just after the procedure (68 vs. 20 mmHg; P < 0.001). Peak serum creatine kinase-myocardial band and troponin I levels were 112 (35-282) ng/ml and 11 (4-93) ng/ml. EVOH embolization to diagonal artery was observed in 1 patient (4%) and the complete atrioventricular block was noted in 2 (8%) patients. During the 12-month follow-up, there was no mortality. There was a significant improvement in New York Heart Association functional class of the subjects P < 0.001). Both interventricular septum thickness and LVOT gradient showed a significant reduction during follow-up (P < 0.05). However, there was no reduction in the LVOT gradient of 3 patients (12%). CONCLUSIONS: In conclusion, our small-sized preliminary study results showed that septal reduction therapy using EVOH is an effective alternative option in reducing symptoms and LVOT gradient in HOCM.

What is the rate of patients undergoing a total hip arthroplasty after core decompression and insertion of a tantalum rod in osteonecrosis of the femoral head: a systematic review.

PURPOSE: Core decompression (CD) may be effective when performed during the early stages of osteonecrosis of the femoral head (ONFH). Tantalum may be added as a rod that would allow putting some mechanical constraints on the femoral head. We aimed to estimate the rate of total hip arthroplasty after CD and insertion of a tantalum rod during early stages of OFNH. METHODS: We searched systematically Medline via PubMed and the Cochrane Library. Our primary endpoint was the rate of patients undergoing a total hip arthroplasty after CD and insertion of a tantalum rod. Secondary endpoints were the delay between the initial surgery and the arthroplasty, the functional improvement, and the rate of complications. RESULTS: We included seven  studies reporting the results of 232 patients (297 hips) that were operated on by CD and insertion of a tantalum rod. At a mean follow-up of 26.97 months, 24.63% of the included hips underwent a hip arthroplasty (6-56%, SD = 17.34%). The mean delay between the initial surgery and the arthroplasty was 14.94 months (10.20-22.90; SD = 5.25), the mean improvement of Harris Hip Score was 27.66 (20.20-36.90; SD = 6.48), and the mean rate of femoral fracture was 2.43% (0-13%, SD = 4.89%). CONCLUSION: CD and insertion of a tantalum rod may represent a solution in order to improve the mechanical support and to give a rate of conversion in arthroplasty that is acceptable.

Early and midterm outcomes after transcatheter embolization of type I endoleaks in 25 patients.

OBJECTIVE: This study reports the technical success and follow-up results of transcatheter embolization of type I endoleak (ELI) in 25 patients after endovascular aortic repair (EVAR). METHODS: Twenty-five patients with ELI (20 men, five women; mean age 80 years; range, 64-96 years) underwent embolization of abdominal ELI (23 proximal, 2 distal endoleaks) after EVAR. All patients were unsuitable for standard endovascular methods for treatment of ELI. The average aneurysm sac size before embolization was 8.2 cm (range, 5.3-12.9 cm). The average time between EVAR and endoleak diagnosis was 685 days (range, 1-4220 days) and from endoleak diagnosis to embolization was 27 days (range, 2-94 days). Onyx (ev3 Endovascular, Inc, Plymouth, Minn) alone or with detachable coils was used for embolization. RESULTS: A total of 27 embolization procedures were performed, with two patients having undergone a repeat procedure. Onyx alone was used in 16 cases and Onyx and coils were used in 11. Immediate technical success with complete isolation of the endoleak on completion angiography was achieved in all procedures. Six procedural complications occurred: three puncture site hematomas and three cases of non-target Onyx embolization. None of the complications had long term sequelae. During the follow-up period (average, 311 days; range, 1-1357 days), seven patients (28%) developed endoleak recurrence, and two underwent a second embolization procedure. Of these, one has had no further endoleak recurrence, but the other developed a recurrent endoleak and died of sac rupture. Two of the other five cases of endoleak recurrence were successfully managed by other procedures, one had a persistent endoleak despite aortic cuff placement, and the other two were deemed unsuitable for further intervention. Three of the four patients with persistent endoleaks died of sac rupture. At the average follow-up time of 311 days, freedom from endoleak recurrence was 80%, and freedom from sac growth was 85%. CONCLUSIONS: Transcatheter embolization of ELI offers a safe, feasible, and sustainable treatment option for patients who are unsuitable for standard methods of ELI treatment. Additional coil embolization before Onyx injection may result in better outcome.

Multi-elemental nanoparticle exposure after tantalum component failure in hip arthroplasty: In-depth analysis of a single case.

Porous tantalum components are widely used for complex acetabular reconstructions in revision hip arthroplasty. Multiple other metal alloys such as titanium-aluminum-vanadium or cobalt-chromium-molybdenum are principally used in artificial joint setups. We report a case of tantalum component failure being both cause and effect of a multiple metal exposure. Our aims were to assess and to characterize associated particle exposure and biological consequences. Metal level quantification revealed substantial in vivo exposure to particulate and dissociated tantalum, zirconium, chromium, cobalt, molybdenum, titanium, aluminum and vanadium in periprosthetic compartments. Aside from micron-sized particles, nanoparticles of a broad size range and elemental composition were obtained. Histological exams verified a spectrum of necrotic changes in the periprosthetic tissues. In the presented case tantalum release was accompanied by concomitance of particles originating from other utilized metals. We conclude that an overall in vivo exposure assessment is mandatory for realistic appraisal of metal toxicity and associated risks.

Long-term results of intra-arterial onyx injection for type II endoleaks following endovascular aneurysm repair.

Purpose The aim of this paper is to report our experience of type II endoleak treatment after endovascular aneurysm repair with intra-arterial injection of the embolizing liquid material, Onyx liquid embolic system. Methods From 2005 to 2012, we performed a retrospective review of 600 patients, who underwent endovascular repair of an abdominal aortic aneurysm. During this period, 18 patients were treated with Onyx for type II endoleaks. Principal findings The source of the endoleak was the internal iliac artery in seven cases, inferior mesenteric artery in seven cases and lumbar arteries in four cases. Immediate technical success was achieved in all patients and no endoleak from the treated vessel recurred. During a mean follow-up of 19 months, no major morbidity or mortality occurred, and one-year survival was 100%. Conclusions Treatment of type II endoleaks with Onyx is safe and effective over a significant time period.

Tantalum rod implantation for femoral head osteonecrosis: survivorship analysis and determination of prognostic factors for total hip arthroplasty.

PURPOSE: The purpose of this study was to evaluate the moderate survival data of porous tantalum rod implants for the treatment of osteonecrosis of the femoral head (ONFH). Additionally, some independent prognostic factors for conversion to total hip arthroplasty (THA) were identified. METHODS: The porous tantalum rod population was obtained from a prospective, consecutive group of patients treated for Steinberg stage I and II osteonecrosis from April 2009 through July 2011. The historical core decompression and impaction of bone filling particle subjects underwent surgery from April 2007 through March 2009. Surgical data including time of surgery, blood loss, and cell transfusions were recorded. Post-operative values were measured for hospitalization length as well as days requiring a patient-controlled analgesia (PCA) pump. Primary outcomes were Harris hip score and survivorship analysis. Demographics and baseline characteristics included age, sex, etiology, bilateral disease, associated chronic systemic disease, Steinberg stage, Harris hip score, accompanied with bone marrow edema of femoral head, and osteonecrotic lesion size. RESULTS: Demographic/baseline characteristics were similar between two groups. At the post-operative follow-up of 62 months, Harris hip scores were significantly increased (P < 0.0001) when compared to that before surgery in both groups. The magnitude of increase in the tantalum rod implant group was significantly greater than that in the control group (P = 0.0426). With an average follow-up of 48 months (range, 38-62 months), the tantalum rod group had an 84.6 % survival rate. With an average follow-up of 72 months (range, 67-85 months), the control group had a 63.3 % survival rate. A comparison of Kaplan-Meier curves showed significantly higher cumulative survival rates (P = 0.048) for hips with implantation of the porous tantalum rod (74.1 % at 62 months) than for those with impaction composite bone material (49.9 % at 62 months). The Cox proportional-hazard model revealed that implantation of tantalum rod (P = 0.012), bone marrow edema (P = 0.003), corticosteroids intake (P = 0.007), and age less than 50 years (P = 0.014) were the independent prognostic factors related to conversion into THA. CONCLUSIONS: Compared with the traditional impaction composite bone material technique, implantation of tantalum rod in the treatment of Steinberg stages I and II ONFH can obtain better clinical results and higher cumulative survival rates. For patients without the use of corticosteroids, and especially for hips without bone marrow oedema, the clinical results from our study show highly encouraging survival rates and a delay in or prevention of conversion into THA.

Clinical and radiographic evaluation of total hip arthroplasties using porous tantalum modular acetabular components: 5-year follow-up of clinical trial.

OBJECTIVES: Porous tantalum is a biomaterial newly applied for artificial joints. We present here 5-years follow-up report of a multicenter clinical trial of total hip arthroplasties (THA) with porous tantalum modular acetabular component (modular PTC). METHODS: Study participants received 82 hips in 79 cases, with 61.2 months follow-up on average. Age at operation was 60.9 years. Clinical results were evaluated using Merle d'Aubigne Postel score. Presence of implant loosening, periacetabular radiolucency, osteolysis, and gap filling were examined for radiographic results. RESULTS: Merle d'Aubigne Postel score improved from 10.0 to 16.4 points. All PTC were radiographically stable, with no evidence of progressive radiolucencies. Average polyethylene wear rate was 0.004 mm/year, with no periacetabular osteolysis. Fifteen hips (18.3%) showed a gap >1 mm; however, all showed bone filling within 12 months. PTC with oversized reaming was significantly less likely to have a gap. No implant failure was noted related to modularity. Resulting survival rate of modular PTC was 100% at 5 years. CONCLUSIONS: Modular PTC showed excellent results at 5-years of follow-up. Some hips showed periacetabular gaps, which were filled with bone within 1 year. Further follow-up was needed to determine long-term efficacy.

Improved results using Onyx glue for the treatment of persistent type 2 endoleak after endovascular aneurysm repair.

OBJECTIVE: Persistent type 2 (PT2) endoleaks (present ≥ 6 months) after endovascular aneurysm repair are associated with adverse outcomes, and selective secondary intervention is indicated in those patients with an expanding aneurysm sac. This study evaluated the outcomes of secondary intervention for PT2. METHODS: From 1999 to 2007, 136 patients who underwent endovascular aneurysm repair developed PT2 and comprised the study cohort. Primary end points included PT2 resolution (secondary interventional success) and survival, and were evaluated using multiple logistic regression and Kaplan-Meier analyses, respectively. RESULTS: Fifty-one patients underwent a total of 68 secondary interventions for PT2 with expanding aneurysm sacs with a median postsecondary interventional follow-up of 13.7 months. Secondary interventions included 20 inferior mesenteric artery coil embolizations, 17 Onyx glue embolizations, 11 aneurysm sac coil embolizations, 10 non-Onyx glue embolizations, 7 lumbar artery coil embolizations, 2 open lumbar ligations, and 1 graft explant. The overall secondary interventional success rate was 43% (29 of 68). Onyx glue embolization was associated with a greater success rate when used as the initial secondary intervention (odds ratio, 59.61; 95% confidence interval, 4.78-742.73; P < .001). There was no difference in success between the different techniques when multiple secondary interventions were required. Five-year survival was 72% ± 0.08% and was unrelated to any of the secondary interventional techniques. CONCLUSIONS: Secondary intervention for PT2 is associated with success in less than half of all cases. Onyx glue embolization was associated with greater long-term success when used as the initial secondary intervention.

[Characteristics of psychologic features of tantalum production workers].

The article covers results of psychologic examination of apparently healthy workers of contemporary tantalum production. The authors describe changes in psychoemotional state of workers engaged into major tantalum production workshops, in accordance with occupational length of service.

Hemocompatibility investigation of the NiTi alloy implanted with tantalum.

A composite TiO(2)/Ta(2)O(5) nano-film has been formed on the NiTi shape memory alloy by Ta implantation. The wettability, protein adsorption, platelets adhesion and hemolysis tests are conducted to evaluate the hemocompatibility. The contact angle measurements showed that the surface of the NiTi alloy kept hydrophilic before and after Ta implantation, although the water contact angle increased with the increasing of implantation current. Both of the surface energy and the interfacial tension decreased after Ta implantation. The protein adsorption behavior was investigated by (125)I isotope labeling. The fibrinogen adsorption was enhanced by a high surface roughness or a large interfacial tension, while the albumin adsorption was insensitive to the surface modification. Platelet adhesion and activation were weakened and the hemolysis rate was reduced at least 46% after Ta implantation due to the decreased surface energy and improved corrosion resistance ability, respectively.

Preliminary results of an uncemented trabecular metal tibial component in total knee arthroplasty.

Trabecular metal has several theoretical advantages for the long-term survival of a tibial component. We report the results of a prospective cohort of 105 consecutive primary total knee arthroplasties using an uncemented trabecular metal (tantalum) tibial component at a minimum 3-year follow-up (range, 36-56 months). There was a significant improvement in Oxford Knee scores and Short Form-12 scores postoperatively. There was no radiolucency at the implant-bone interface on any postoperative radiograph. There has been one (1%) revision of the tibial component for trauma. The 3-year results using this prosthesis are as good as those published for the commonly used cemented prostheses. Longer follow-up is required to see whether these results are maintained over time.

Beam hardening artifacts of liquid embolic agents: comparison between Squid and Onyx.

BACKGROUND: Initial clinical experience with Squid shows subjectively reduced artifacts on post-embolization CT scans compared with Onyx. To further investigate these observations, we aimed to perform a comparison of artifacts between Squid and Onyx in a controlled in vitro model. MATERIALS AND METHODS: Onyx 18 and all four variants of Squid (Squid 18, Squid 18 low density (LD), Squid 12, Squid 12 LD) were each injected in dimethylsulfoxide (DMSO) compatible test tubes. The tubes containing precipitated embolic material were inserted in a CT phantom for conventional and flat panel CT acquisitions. Beam hardening artifacts were quantified using objective and subjective measurements. RESULTS: Objective evaluation of artifacts within regions of interest (ROIs) placed around the embolic material on CT and flat panel CT images demonstrated significantly lower noise and Hounsfield unit (HU) range values for all four Squid products compared with Onyx 18. On both CT and flat panel CT, LD variants of Squid 18 and Squid 12 had significantly lower noise and HU range values than their normal density counterparts on longitudinal ROIs. When using subjective measures for diagnostic value within ROIs placed around the embolic material on both CT and flat panel CT images, the number of non-diagnostic ROIs was significantly higher for Onyx 18 than for all four Squid variants. CONCLUSION: All four variants of Squid induced fewer beam hardening artifacts than Onyx 18 on CT and flat panel CT acquisitions. LD variants of Squid induced fewer artifacts than their normal density counterparts.

May the Inferior Petrosal Sinus Recanalization During Endovascular Treatment for Carotid-Cavernous Fistulas Increase the Risk of Sixth Nerve Palsy?

BACKGROUND: Sixth nerve palsy is a common complication of endovascular treatment for carotid-cavernous fistulas (CCF). Two hypotheses are evoked: the spontaneous venous congestion into the cavernous sinus and the direct compression of the nerve by the embolic agent into the cavernous sinus. Nevertheless, the evidence is still uncertain. Knowing the vicinity of the sixth nerve with the inferior petrosal sinus (IPS) in the Dorello canal, we hypothesized that the recanalization of the IPS increased the risk of nerve damage. METHODS: We analyzed a prospective database of patients treated for CCFs from March 2009 to April 2016. We excluded patients who did not need treatment, cases of high-flow CCF, and patients lost to follow-up, obtaining a homogeneous population of 82 patients with indirect CCFs. This population was divided in 2 groups: patients without new-onset/worsening of sixth nerve palsy and patients with this postprocedural complication. RESULTS: Our main endpoints were the potential differences between patients with or without recanalization of IPS and between those who underwent or not an embolization with Onyx-18. We did not find any statistically meaningful difference between the 2 groups concerning the necessity of IPS recanalization (P > 0.999, odds ratio 0.97, 95% confidence interval 0.32-2.96) or with the use of Onyx-18 as an embolic agent (P = 0.56; odds ratio 1.41, 95% confidence interval 0.41-2.45). CONCLUSIONS: The recanalization of a thrombosed IPS does not increase the risk of procedural sixth nerve damage. The initial injury seems to relate with development/worsening of a sixth nerve palsy.

Development of syndrome of inappropriate antidiuretic hormone secretion (SIADH) after Onyx embolisation of a cavernous carotid fistula.

Patients with cavernous carotid fistulas (CCFs) can present with pituitary hypoperfusion and hypopituitarism; however, there are no previous reports of pituitary or hormonal abnormalities developing after CCF embolisation in an asymptomatic patient. We describe a patient with no hormonal abnormalities who developed syndrome of inappropriate antidiuretic hormone (SIADH) secretion after CCF embolisation. The patient had bilateral indirect CCFs, which were completely embolised via a transvenous approach, and was neurologically stable postoperatively and discharged. In the subsequent 2 weeks the patient was readmitted twice for acute hyponatraemia and a tonic-clonic seizure. Laboratory studies revealed severe SIADH. Clinical status and sodium levels improved after treatment. One year later the patient was weaned off all medications and remained neurologically stable. SIADH may be a delayed phenomenon after CCF embolisation. Given the proximity of embolised vessels to the pituitary's vascular supply, CCF treatment may result in flow disturbance, ischaemia and hormonal abnormalities.