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  • 1
    Online Resource
    Online Resource
    Thrombectomy for M2 Occlusions: Predictors of Successful and Futile Recanalization
    Ovid Technologies (Wolters Kluwer Health) ; 2023
    In:  Stroke Vol. 54, No. 8 ( 2023-08), p. 2002-2012
    Details
    In: Stroke, Ovid Technologies (Wolters Kluwer Health), Vol. 54, No. 8 ( 2023-08), p. 2002-2012
    Abstract: Patient-specific factors associated with successful recanalization in mechanical thrombectomy (MT) have been evaluated for acute ischemic stroke with large vessel occlusion. However, MT for M2 occlusions is still a matter of debate, and predictors of successful and futile recanalization have not been assessed in detail. We sought to identify predictors of recanalization success in patients with M2 occlusions undergoing MT based on large-scale clinical data. METHODS: All patients prospectively enrolled in the German Stroke Registry (May, 2015 to December, 2021) were screened (N=13 082). Inclusion criteria for the complete case analysis were isolated M2 occlusions. Standard descriptive statistics and multivariable logistic regression analysis were used to identify factors associated with successful recanalization (Thrombolysis in Cerebral Infarction [TICI]≥2b), complete recanalization (TICI=3) and futile recanalization (TICI≥2b with 90-day modified Rankin Scale [mRS] score 〉 2). RESULTS: One thousand two hundred ninety-four patients were included, thereof 439 (33.9%) with TICI=2b and 643 (49.7%) with TICI=3. Five hundred sixty-nine (44%) patients had good functional outcome (90-day mRS score ≤2). In multivariable logistic regression, general anesthesia (adjusted odds ratio [aOR], 1.47 [95% CI, 1.05–2.09] ; P 〈 0.05) was associated with higher probability of TICI≥2b while intraprocedural change from local to general anesthesia (aOR, 0.49 [0.26–0.95]; P 〈 0.05) and higher pre-mRS (aOR, 0.75 [0.67–0.85]; P 〈 0.001) lowered probability of successful recanalization. Futile recanalization was associated with higher age (aOR, 1.05 [1.04–1.07]; P 〈 0.001), higher prestroke mRS (aOR, 3.12 [2.49–3.91]; P 〈 0.001), higher NIHSS at admission (aOR, 1.11 [1.08–1.14]; P 〈 0.001), diabetes (aOR, 1.96 [1.38–2.8]; P 〈 0.001), higher number of passes (aOR, 1.29 [1.14–1.46]; P 〈 0.001), and adverse events (aOR, 1.82 [1.2–2.74]; P 〈 0.01). Higher Alberta Stroke Program Early CT Score (aOR, 0.85 [0.76–0.94]; P 〈 0.01) and IV thrombolysis (aOR, 0.71 [0.52–0.97]; P 〈 0.05) reduced risk of futile recanalization. CONCLUSIONS: In patients with M2 occlusions, successful recanalization was significantly associated with general anesthesia and low prestroke mRS, while intraprocedural change from conscious sedation to general anesthesia increased risk of unsuccessful recanalization, presumably caused by difficult anatomy and movement of patients in these cases. Futile recanalization was associated with severe prestroke mRS, comorbidity diabetes, number of passes and adverse events during treatment. IV thrombolysis reduced the risk of futile recanalization.
    Type of Medium: Online Resource
    ISSN: 0039-2499 , 1524-4628
    URL: Article
    DOI: 10.1161/STROKEAHA.123.043285
    RVK:
    XA 10000
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2023
    detail.hit.zdb_id: 1467823-8
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  • 2
    Online Resource
    Online Resource
    Association of Thrombectomy With Functional Outcome for Patients With Ischemic Stroke Who Presented in the Extended Time Window With Extensive Signs of Infarction
    American Medical Association (AMA) ; 2022
    In:  JAMA Network Open Vol. 5, No. 10 ( 2022-10-14), p. e2235733-
    Details
    In: JAMA Network Open, American Medical Association (AMA), Vol. 5, No. 10 ( 2022-10-14), p. e2235733-
    Abstract: Only limited data are available about a potential benefit associated with endovascular treatment (EVT) for patients with ischemic stroke presenting in the extended time window who also show signs of extensive infarction. Objective To assess the association of recanalization after EVT with functional outcomes for patients with ischemic stroke presenting in the extended time window who also show signs of extensive infarction. Design, Setting, and Participants This retrospective, multicenter cohort study included patients enrolled in the German Stroke Registry–Endovascular Treatment with an Alberta Stroke Program Early CT Score (ASPECTS) of 5 or less who presented between 6 and 24 hours after stroke onset and underwent computed tomography and subsequent EVT between July 1, 2015, and December 31, 2019. Main Outcomes and Measures The primary end point was a modified Rankin Scale (mRS) score of 3 or less at day 90. The association between recanalization (defined as the occurrence of a modified Thrombolysis in Cerebral Infarction Scale score of 2b or 3) and outcome was assessed using logistic regression and inverse probability weighting analysis. Intervention Endovascular treatment. Results Of 5853 patients, 285 (5%; 146 men [51%]; median age, 73 years [IQR, 62-81 years] ) met the inclusion criteria and were analyzed. Of these 285 patients, 79 (27.7%) had an mRS score of 3 or less at day 90. The rate of successful recanalization was 75% (215 of 285) and was independently associated with a higher probability of reaching an mRS score of 3 or less (adjusted odds ratio, 4.39; 95% CI, 1.79-10.72; P   & amp;lt; .001). In inverse probability weighting analysis, a modified Thrombolysis in Cerebral Infarction Scale score of 2b or 3 was associated with a 19% increase (95% CI, 9%-29%; P   & amp;lt; .001) in the probability for an mRS score of 3 or more. Multivariable logistic regression analysis suggested a significant treatment benefit associated with vessel recanalization in a time window of up to 17.6 hours and ASPECTS of 3 to 5. The rate of secondary symptomatic intracerebral hemorrhage was 6.3% (18 of 285). Conclusions and Relevance In this cohort study reflecting daily clinical practice, vessel recanalization for patients with a low ASPECTS and extended time window was associated with better functional outcomes in a time window up to 17.6 hours and ASPECTS of 3 to 5. The results of this study encourage current randomized clinical trials to enroll patients with a low ASPECTS, even within the extended time window.
    Type of Medium: Online Resource
    ISSN: 2574-3805
    URL: Article
    DOI: 10.1001/jamanetworkopen.2022.35733
    Language: English
    Publisher: American Medical Association (AMA)
    Publication Date: 2022
    detail.hit.zdb_id: 2931249-8
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  • 3
    Online Resource
    Online Resource
    Association Between Intravenous Thrombolysis and Clinical Outcomes Among Patients With Ischemic Stroke and Unsuccessful Mechanical Reperfusion
    American Medical Association (AMA) ; 2023
    In:  JAMA Network Open Vol. 6, No. 5 ( 2023-05-01), p. e2310213-
    Details
    In: JAMA Network Open, American Medical Association (AMA), Vol. 6, No. 5 ( 2023-05-01), p. e2310213-
    Abstract: Clinical evidence of the potential treatment benefit of intravenous thrombolysis preceding unsuccessful mechanical thrombectomy (MT) is scarce. Objective To determine whether intravenous thrombolysis (IVT) prior to unsuccessful MT improves functional outcomes in patients with acute ischemic stroke. Design, Setting, and Participants Patients were enrolled in this retrospective cohort study from the prospective, observational, multicenter German Stroke Registry–Endovascular Treatment between May 1, 2015, and December 31, 2021. This study compared IVT plus MT vs MT alone in patients with acute ischemic stroke due to anterior circulation large-vessel occlusion in whom mechanical reperfusion was unsuccessful. Unsuccessful mechanical reperfusion was defined as failed (final modified Thrombolysis in Cerebral Infarction grade of 0 or 1) or partial (grade 2a). Patients meeting the inclusion criteria were matched by treatment group using 1:1 propensity score matching. Interventions Mechanical thrombectomy with or without IVT. Main Outcomes and Measures Primary outcome was functional independence at 90 days, defined as a modified Rankin Scale score of 0 to 2. Safety outcomes were the occurrence of symptomatic intracranial hemorrhage and death. Results After matching, 746 patients were compared by treatment arms (median age, 78 [IQR, 68-84] years; 438 women [58.7%] ). The proportion of patients who were functionally independent at 90 days was 68 of 373 (18.2%) in the IVT plus MT and 42 of 373 (11.3%) in the MT alone group (adjusted odds ratio [AOR], 2.63 [95% CI, 1.41-5.11] ; P  = .003). There was a shift toward better functional outcomes on the modified Rankin Scale favoring IVT plus MT (adjusted common OR, 1.98 [95% CI, 1.35-2.92]; P   & amp;lt; .001). The treatment benefit of IVT was greater in patients with partial reperfusion compared with failed reperfusion. There was no difference in symptomatic intracranial hemorrhages between treatment groups (AOR, 0.71 [95% CI, 0.29-1.81]; P  = .45), while the death rate was lower after IVT plus MT (AOR, 0.54 [95% CI, 0.34-0.86]; P  = .01). Conclusions and Relevance These findings suggest that prior IVT was safe and improved functional outcomes at 90 days. Partial reperfusion was associated with a greater treatment benefit of IVT, indicating a positive interaction between IVT and MT. These results support current guidelines that all eligible patients with stroke should receive IVT before MT and add a new perspective to the debate on noninferiority of combined stroke treatment.
    Type of Medium: Online Resource
    ISSN: 2574-3805
    URL: Article
    DOI: 10.1001/jamanetworkopen.2023.10213
    Language: English
    Publisher: American Medical Association (AMA)
    Publication Date: 2023
    detail.hit.zdb_id: 2931249-8
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  • 4
    Online Resource
    Online Resource
    Study Criteria Applied to Real Life—A Multicenter Analysis of Stroke Patients Undergoing Endovascular Treatment in Clinical Practice
    Ovid Technologies (Wolters Kluwer Health) ; 2021
    In:  Journal of the American Heart Association Vol. 10, No. 22 ( 2021-11-16)
    Details
    In: Journal of the American Heart Association, Ovid Technologies (Wolters Kluwer Health), Vol. 10, No. 22 ( 2021-11-16)
    Abstract: Randomized controlled clinical trials (RCT) have demonstrated the efficacy of endovascular treatment in anterior circulation large vessel occlusions. However, outcome of patients treated in daily practice differs from the results of the clinical trials. We hypothesize that this is attributable to the study criteria and that application of the criteria on patients undergoing endovascular therapy in daily routine would improve their outcome. Methods and Results Data from a multicenter prospective registry of GSR‐ET (German Stroke Registry – Endovascular Treatment) was used. Inclusion criteria and selectivity of SWIFT‐PRIME (Solitaire with the Intention for Thrombectomy as Primary Endovascular Treatment trial), MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands trial), ESCAPE (Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion with Emphasis on Minimizing CT to Recanalization Times trial), DAWN (DWI or CTP Assessment with Clinical Mismatch in the Triage of Wake‐Up and Late Presenting Strokes Undergoing Neurointervention with Trevo trial) and DEFUSE‐3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke trial) trials were analyzed. Baseline characteristics, procedural and outcome data of patients from GSR‐ET before and after selection were compared with the results of the RCTs. Furthermore, outcome of patients who underwent endovascular treatment despite not fulfilling the RCT criteria was analyzed. A total of 2611 patients were included (median age, 75 years; 49.6% women; median National Institute of Health Stroke Scale, 16). A minority of patients met all inclusion criteria, ranging from 3% (DEFUSE‐3 criteria) to 35% (MR CLEAN criteria). Of the patients fulfilling the MR CLEAN criteria, 41% of patients had a good clinical outcome, compared with 34% of patients that did not fulfill MR CLEAN criteria. Conclusions The RCTs represent a selected population with higher rates of good clinical outcome compared with daily practice. The good outcomes of RCTs can be reproduced in clinical routine in patients who fulfill the RCT inclusion criteria. Furthermore, patients who did not meet the criteria of the RCT still had substantial rates of good clinical outcome.
    Type of Medium: Online Resource
    ISSN: 2047-9980
    URL: Article
    DOI: 10.1161/JAHA.120.017919
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2021
    detail.hit.zdb_id: 2653953-6
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  • 5
    Online Resource
    Online Resource
    Association Between Recanalization Attempts and Functional Outcome After Thrombectomy for Large Ischemic Stroke
    Ovid Technologies (Wolters Kluwer Health) ; 2023
    In:  Stroke Vol. 54, No. 9 ( 2023-09), p. 2304-2312
    Details
    In: Stroke, Ovid Technologies (Wolters Kluwer Health), Vol. 54, No. 9 ( 2023-09), p. 2304-2312
    Abstract: Recently, 3 randomized controlled trials provided high-level evidence that patients with large ischemic stroke achieved better functional outcomes after endovascular therapy than with medical care alone. We aimed to investigate whether the clinical benefit of endovascular therapy is associated with the number of recanalization attempts in extensive baseline infarction. METHODS: This retrospective multicenter study enrolled patients from the German Stroke Registry who underwent endovascular therapy for anterior circulation large vessel occlusion between 2015 and 2021. Large ischemic stroke was defined as an Alberta Stroke Program Early Computed Tomography Score of 3 to 5. The study cohort was divided into patients with unsuccessful reperfusion (Thrombolysis in Cerebral Infarction score, 0–2a) and successful reperfusion (Thrombolysis in Cerebral Infarction score, 2b/3) at attempts 1, 2, 3, or ≥4. The primary outcome was favorable functional outcome defined as modified Rankin Scale score of 0 to 3 at 90 days. Safety outcomes were symptomatic intracranial hemorrhage after 24 hours and death within 90 days. Multivariable logistic regression was used to identify independent determinants of primary and secondary outcomes. RESULTS: A total of 348 patients met the inclusion criteria. Successful reperfusion was observed in 83.3% and favorable functional outcomes in 36.2%. Successful reperfusion at attempts 1 (adjusted odds ratio, 5.97 [95% CI, 1.71–24.43]; P =0.008) and 2 (adjusted odds ratio, 6.32 [95% CI, 1.73–26.92]; P =0.008) increased the odds of favorable functional outcome, whereas success at attempts 3 or ≥4 did not. Patients with 〉 2 attempts showed higher rates of symptomatic intracranial hemorrhage (12.8% versus 6.5%; P =0.046). Successful reperfusion at any attempt lowered the odds of death compared with unsuccessful reperfusion. CONCLUSIONS: In patients with large vessel occlusion and Alberta Stroke Program Early Computed Tomography Score of 3 to 5, the clinical benefit of endovascular therapy was linked to the number of recanalization attempts required for successful reperfusion. Our findings encourage to perform at least 2 recanalization attempts to seek for successful reperfusion in large ischemic strokes, while 〉 2 attempts should follow a careful risk-benefit assessment in these highly affected patients. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03356392.
    Type of Medium: Online Resource
    ISSN: 0039-2499 , 1524-4628
    URL: Article
    DOI: 10.1161/STROKEAHA.123.042794
    RVK:
    XA 10000
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2023
    detail.hit.zdb_id: 1467823-8
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  • 6
    Online Resource
    Online Resource
    Good Clinical Outcome Decreases With Number of Retrieval Attempts in Stroke Thrombectomy : Beyond the First-Pass Effect
    Ovid Technologies (Wolters Kluwer Health) ; 2021
    In:  Stroke Vol. 52, No. 2 ( 2021-02), p. 482-490
    Details
    In: Stroke, Ovid Technologies (Wolters Kluwer Health), Vol. 52, No. 2 ( 2021-02), p. 482-490
    Abstract: Endovascular therapy is the standard of care in the treatment of acute ischemic stroke due to large-vessel occlusion. Often, more than one retrieval attempt is needed to achieve reperfusion. We aimed to quantify the influence of endovascular therapy on clinical outcome depending on the number of retrievals needed for successful reperfusion in a large multi-center cohort. Methods: For this observational cohort study, 2611 patients from the prospective German Stroke Registry included between June 2015 and April 2018 were analyzed. Patients who received endovascular therapy for acute anterior circulation stroke with known admission National Institutes of Health Stroke Scale score and Alberta Stroke Program Early CT Score, final Thrombolysis in Cerebral Infarction score, and number of retrievals were included. Successful reperfusion was defined as a Thrombolysis in Cerebral Infarction score of 2b or 3. The primary outcome was defined as functional independence (modified Rankin Scale score of 0–2) at day 90. Multivariate mixed-effects models were used to adjust for cluster effects of the participating centers and confounders. Results: The inclusion criteria were met by 1225 patients. The odds of good clinical outcome decreased with every retrieval attempt required for successful reperfusion: the first retrieval had the highest odds of good clinical outcome (adjusted odds ratio, 6.45 [95% CI, 4.0–10.4]), followed by the second attempt (adjusted odds ratio, 4.56 [95% CI, 2.7–7.7] ), and finally the third (adjusted odds ratio, 3.16 [95% CI, 1.8–5.6]). Conclusions: Successful reperfusion within the first 3 retrieval attempts is associated with improved clinical outcome compared with patients without reperfusion. We conclude that at least 3 retrieval attempts should be performed in endovascular therapy of anterior circulation strokes. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03356392.
    Type of Medium: Online Resource
    ISSN: 0039-2499 , 1524-4628
    URL: Article
    DOI: 10.1161/STROKEAHA.120.029830
    RVK:
    XA 10000
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2021
    detail.hit.zdb_id: 1467823-8
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  • 7
    Online Resource
    Online Resource
    Category and design fluency in mild cognitive impairment: Performance, strategy use, and neural correlates
    Elsevier BV ; 2016
    In:  Neuropsychologia Vol. 93 ( 2016-12), p. 21-29
    Details
    In: Neuropsychologia, Elsevier BV, Vol. 93 ( 2016-12), p. 21-29
    Type of Medium: Online Resource
    ISSN: 0028-3932
    URL: Article
    DOI: 10.1016/j.neuropsychologia.2016.09.024
    RVK:
    XA 10000
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2016
    detail.hit.zdb_id: 1500656-6
    SSG: 5,2
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  • 8
    Online Resource
    Online Resource
    Frequency and Chunking in Derived Words: A Parametric fMRI Study
    MIT Press ; 2017
    In:  Journal of Cognitive Neuroscience Vol. 29, No. 7 ( 2017-07-01), p. 1162-1177
    Details
    In: Journal of Cognitive Neuroscience, MIT Press, Vol. 29, No. 7 ( 2017-07-01), p. 1162-1177
    Abstract: In usage-based linguistic theories, the assumption that high-frequency language strings are mentally represented as unitary chunks has been invoked to account for a wide range of phenomena. However, neurocognitive evidence in support of this assumption is still lacking. In line with Gestalt psychological assumptions, we propose that a language string qualifies as a chunk if the following two conditions are simultaneously satisfied: The perception of the whole string does not involve strong activation of its individual component parts, but the component parts in isolation strongly evoke the whole. Against this background, we explore the relationship between different frequency metrics and the chunk status of derived words (e.g., “government,” “worthless”) in a masked visual priming experiment with two conditions of interest. One condition investigates “whole-to-part” priming (worthless–WORTH), whereas the other one analyzes “part-to-whole” priming (tear–TEARLESS). Both conditions combine mixed-effects regression analyses of lexical decision RTs with a parametric fMRI design. Relative frequency (the frequency of the whole word relative to that of its onset-embedded part) emerges as the only frequency metric to correlate with chunk status in behavioral terms. The fMRI results show that relative frequency modulates activity in regions that have been related to morphological (de)composition or general task performance difficulty (notably left inferior frontal areas) and in regions associated with competition between whole, undecomposed words (right inferior frontal areas). We conclude that relative frequency affects early stages of processing, thereby supporting the usage-based concept of frequency-induced chunks.
    Type of Medium: Online Resource
    ISSN: 0898-929X , 1530-8898
    URL: Article
    DOI: 10.1162/jocn_a_01120
    Language: English
    Publisher: MIT Press
    Publication Date: 2017
    SSG: 5,2
    SSG: 7,11
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  • 9
    Online Resource
    Online Resource
    Periprocedural aspects in mechanical recanalization for acute stroke: data from the ENDOSTROKE registry
    Springer Science and Business Media LLC ; 2013
    In:  Neuroradiology Vol. 55, No. 9 ( 2013-9), p. 1143-1151
    Details
    In: Neuroradiology, Springer Science and Business Media LLC, Vol. 55, No. 9 ( 2013-9), p. 1143-1151
    Type of Medium: Online Resource
    ISSN: 0028-3940 , 1432-1920
    URL: Article
    DOI: 10.1007/s00234-013-1219-9
    RVK:
    XA 10000
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2013
    detail.hit.zdb_id: 1462953-7
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  • 10
    Online Resource
    Online Resource
    Insights into Imprinting: How Is the Phenomenon of Tribocorrosion at Head-Neck Taper Interfaces Related to Corrosion, Fretting, and Implant Design Parameters?
    Ovid Technologies (Wolters Kluwer Health) ; 2022
    In:  Clinical Orthopaedics & Related Research Vol. 480, No. 8 ( 2022-08), p. 1585-1600
    Details
    In: Clinical Orthopaedics & Related Research, Ovid Technologies (Wolters Kluwer Health), Vol. 480, No. 8 ( 2022-08), p. 1585-1600
    Abstract: Wear and corrosion at modular neck tapers in THA can lead to major clinical implications such as periprosthetic osteolysis, adverse local tissue reactions, or implant failure. The material degradation processes at the taper interface are complex and involve fretting corrosion, third-body abrasion, as well as electrochemical and crevice corrosion. One phenomenon in this context is imprinting of the head taper, where the initially smooth surface develops a topography that reflects the rougher neck taper profile. The formation mechanism of this specific phenomenon, and its relation to other observed damage features, is unclear. An analysis of retrieved implants may offer some insights into this process. Questions/purposes (1) Is imprinting related to time in situ of the implants and to the taper damage modes of corrosion and fretting? (2) Are implant design parameters like neck taper profile, stem material, or head seating associated with the formation of imprinting? (3) Is imprinting created by an impression of the neck taper profile or can a different mechanistic explanation for imprinting be derived? Methods Thirty-one THAs with cobalt-chromium-molybdenum-alloy (CoCrMo) heads retrieved between 2013 and 2019 at revision surgery from an institutional registry were investigated. Inclusion criteria were: 12/14 tapers, a head size of 36 mm or smaller, time in situ more than 1 year, and intact nonmodular stems without sleeve adaptors. After grouping the residual THAs according to stem type, stem material, and manufacturer, all groups of three or more were included. Of the resulting subset of 31 retrievals, nine THAs exhibited a still assembled head-neck taper connection. The median (range) time in situ was 5 years (1 to 23). Two stem materials (21 titanium-alloy and 10 stainless steel), three kinds of bearing couples (11 metal-on-metal, 13 metal-on-polyethylene, and seven dual-mobility heads), and two different neck taper profiles (six wavy profile and 25 fluted profile) were present in the collection. Four THAs exhibited signs of eccentric head seating. The 31 investigated THAs represented 21% of the retrieved THAs with a CoCrMo alloy head during the specified period. At the head tapers, the damage modes of corrosion, fretting, and imprinting were semiquantitatively rated on a scale between 0 (no corrosion/fretting/imprinting) and 3 (severe corrosion/fretting/imprinting). Corrosion and fretting were assessed applying the Goldberg score, with the modification that the scale started at 0 and not at 1. Imprinting was assessed with a custom scoring system. Rating was done individually at the proximal and distal head taper half and summed to one total damage score for each retrieval and damage mode. Correlations between the damage modes and time in situ and between the damage modes among each other, were assessed using the Spearman rank order correlation coefficient (ρ). Associations between imprinting and implant design parameters were investigated by comparing the total imprinting score distributions with the Mann-Whitney U-test. Metallographically prepared cross-sections of assembled head-neck taper connections were examined by optical microscopy and disassembled head and neck taper surfaces were assessed by scanning electron microscopy (SEM). Results The imprinting damage score increased with time in-situ (ρ = 0.72; p 〈 0.001) and the corrosion damage score (ρ = 0.63; p 〈 0.001) but not with the fretting damage score (ρ = 0.35; p = 0.05). There was no difference in total imprinting score comparing neck taper profiles or stem materials, with the numbers available. Eccentric head seating had elevated total imprinting score (median 6 [interquartile range 0]) compared with centric seating (median 1 [2] ; p = 0.001). Light optical investigations showed that imprinting can be present on the head taper surfaces even if the depth of abraded material exceeds the neck taper profile height. SEM investigations showed bands of pitting corrosion in the imprinted grooves. Conclusion The microscopic investigations suggest that imprinting is not an independent phenomenon but a process that accompanies the continuous material degradation of the head taper surface because of circular damage on the passive layer induced by grooved neck tapers. Clinical Relevance Material loss from head-neck taper connections involving CoCrMo alloy heads is a source of metal ions and could potentially be reduced if hip stems with smooth neck tapers were used. Surgeons should pay attention to the exact centric seating of the femoral head onto the stem taper during joining of the parts.
    Type of Medium: Online Resource
    ISSN: 0009-921X , 1528-1132
    URL: Article
    DOI: 10.1097/CORR.0000000000002202
    RVK:
    XA 10000
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2022
    detail.hit.zdb_id: 2018318-5
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