scholarly journals Combined and hybrid marker models for radiostereometry assessment of polyethylene liner motion in dual mobility hip prosthesis: a proof-of-concept study

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Peter Bo Jørgensen ◽  
Bart L. Kaptein ◽  
Kjeld Søballe ◽  
Stig S. Jakobsen ◽  
Maiken Stilling

Abstract Background Investigation of polyethylene liner movement in total hip arthroplasty requires bead-marking for radiographic visibility of the liner. However, occlusion of markers poses a challenge for marker registration in radiographs. Methods The polyethylene of a dual mobility acetabular system was marked with twelve 1-mm tantalum markers (four groups of three markers) using a custom-made drill guide. Liner motion in a phantom and a patient was investigated with dynamic radiostereometry analysis (dRSA) at 1-year follow-up and static radiostereometry analysis (sRSA) postoperatively and at 1- and 2-year follow-up. A combined marker configuration (CMC) model was calculated from the registered positions of the liner markers and the femoral head in several images. Furthermore, the CMC model and the theoretic marker positions from computer-assisted models of the drill guide were combined in a hybrid model. Results The CMC model included eleven markers in the phantom and nine markers in the patient, which was sufficient for dRSA. Liner movement in the phantom followed liner contact with the femoral neck, while liner movement in the patient was independent. The hybrid model was necessary to determine liner orientation in sRSA recordings, which clearly changed from postoperative to 1- and 2-year follow-up even though the patient was positioned similarly. Conclusion Polyethylene liner motion in dual mobility hip prosthesis can be assessed with CMC models in dRSA recordings. In sRSA, the liner position between follow-ups is unpredictable and analysis requires inclusion of all markers in the model, accomplished with a hybrid marker model. Trial registration ClinicalTrials.gov [NCT02301182], 25 October 2015.

Sarcoma ◽  
2003 ◽  
Vol 7 (1) ◽  
pp. 19-27
Author(s):  
G. Delepine ◽  
F. Delepine ◽  
T. Sokolov ◽  
N. Delepine

Purpose: To improve function after pelvic resection involving the acetabulum, using an anatomic composite implant built with screws and cement.Material and method: Since 1990, 66 patients with peri-acetabular bone malignancies have been treated by extensive resection followed by hand-modelled innominate prosthesis with partially constrained total hip prosthesis. The hand-modelled innominate prosthesis was made of a titanium cup, a set of long titanium screws and two or three packs of gentamycine-loaded cement.Results: Many postoperative complications were observed: deep infection (14%), hip prosthesis dislocation (25%) and local recurrence (15%). Sixteen patients (25%) had to be reoperated. Nevertheless, at last follow-up, 62 patients still had composite prosthesis. The mean functional result, rated according to a modified Enneking's staging system, was 80% with unlimited walking without support, average hip flexion 100°, length discrepancy less than 1 cm.Discussion: These results were similar to those described in the literature for custom-made innominate prostheses and much better than those of alternative reconstructive procedures. Hand-modelled composite prostheses are cheaper, easier, more adaptable and enables better anchorage than custom-made prostheses. Such a procedure can be used even after total iliac wing resection.Conclusion: The advantages of such a procedure plead for its extensive use after acetabular resection. But long-term follow-up is necessary to validate indications.


2016 ◽  
Vol 29 (03) ◽  
pp. 259-264
Author(s):  
Pierre Guillaumot ◽  
Jean-Luc Chancrin ◽  
Bertrand Vedrine

SummaryAn eight-year-old male English Setter was referred for management of a dislocation of a cemented dual mobility canine total hip prosthesis that occurred four months after the initial surgery. Revision surgery showed that the dislocation was associated with fracture of the ultra-high molecular weight polyethylene liner. The dislocation was successfully reduced after replacing the liner. A dual mobility acetabular component is composed of a mobile polyethylene liner inside a metallic cemented cup. Chronic wear of the components of a canine dual mobility total hip replacement has not been described previously. The use of this type of implant is fairly recent and limited long term follow-up of the implanted cases may be the explanation. Acute rupture of a polyethylene liner has never been described in humans, the only case of rupture of a polyethylene liner occurred 10 years after implantation. The case presented here of rupture of the polyethylene liner of a dual mobility total hip replacement is a hitherto unreported failure mode in this model of acetabular cup in the dog.


2012 ◽  
Vol 25 (06) ◽  
pp. 511-517 ◽  
Author(s):  
A. Autefage ◽  
T. Dembour ◽  
J.-L. Chancrin ◽  
P. Guillaumot

SummaryObjectives: To report the clinical and radiographic outcome of a canine total hip prosthesis with a dual mobility acetabular component, with a minimum of six months follow-up.Methods: The outcome of dogs that underwent primary cemented unilateral dual mobility hip prosthesis surgery by one of the authors for hip dysplasia or trauma, and which had a minimum of six months clinical and radiologic follow-up, was evaluated.Results: Fifty dogs were included in the study. Follow-up ranged from six to 38 months (mean 14.4 months). Perioperative complications were acetabular collapse (n = 1) and greater trochanter fracture (n = 1), both of which were successfully managed perioperatively. Postoperative complications were aseptic loosening of the acetabular component (n = 2; both surgically revised), implant sepsis (n = 3; all explanted), acetabular fracture (n = 1; conservatively managed), greater trochanter fracture (n = 1; conservatively managed) and sciatic neurapraxia (n = 1). No cases of postoperative luxation or femoral implant aseptic loosening were encountered. Outcome was poor for three cases (3 implant sepsis), fair for three cases (including 1 acetabular component loosening and 1 acetabular fracture), and good or excellent for 44 cases (88%).Clinical significance: There were not any cases of postoperative coxofemoral luxation observed in this series of 50 dogs with dual mobility hip prosthesis. Studies with more patients and longer follow-up are needed to confirm the satisfactory results observed to date with this implant.


2019 ◽  
Author(s):  
Eduardo Joaquim Lopes Alho ◽  
Carlo Rondinoni ◽  
Fabio Okuda Furokawa ◽  
Bernardo A. Monaco

AbstractPurposeThe current assessment of patients with craniofacial asymmetries is accomplished by physical examination, anamnesis and radiological imaging.We propose a semi-automated, computer-assisted craniofacial evaluation (SymMetric v 1.0) based on orthogonal photography of the patient’s head in 3 positions. The system is simple, low-cost, no-radiation or special resources needed. Although it does not substitute CT in cases of doubt between craniosynostosis and positional plagiocephaly, multiple numeric evaluations indicate regional deformities and severity of the asymmetry, which can help in the clinical decision of indicating or not the orthosis in positional deformities, determining treatment duration or evaluating surgical outcomes after correction.MethodsA Matlab-based tool was developed for digital processing of photographs taken in 3 positions (anterior, superior and lateral). The software guides the user to select visible and reproducible landmarks in each photograph acquisition and calculates multiple indexes and metrics, generating a set of comprehensive plots to offer the user an overview of head and facial symmetry across the orthogonal views. For purposes of demonstration, we evaluated 2 patients (one control and one with non-sinostotic deformity).ResultsThe results show a clear differentiation of the control and plagiocephalic patient metrics mainly in the superior view, showing potential for diagnosis of the condition, and also detected the clinical improvement during helmet treatment in the follow-up, 3 and 5 months after orthosis’ use.ConclusionWe presented a proof-of-concept for a low cost, no radiation evaluation system for craniofacial asymmetries, that can be useful in a clinical context for diagnosis and follow-up of patients.


2020 ◽  
Author(s):  
Hongfeng Sheng ◽  
Weixing Xu ◽  
Bin Xu ◽  
Hongpu Song ◽  
Di Lu ◽  
...  

UNSTRUCTURED The retrospective study of Taylor's three-dimensional external fixator for the treatment of tibiofibular fractures provides a theoretical basis for the application of this technology. The paper collected 28 patients with tibiofibular fractures from the Department of Orthopaedics in our hospital from March 2015 to June 2018. After the treatment, the follow-up evaluation of Taylor's three-dimensional external fixator for the treatment of tibiofibular fractures and concurrency the incidence of the disease, as well as the efficacy and occurrence of the internal fixation of the treatment of tibial fractures in our hospital. The results showed that Taylor's three-dimensional external fixator was superior to orthopaedics in the treatment of tibiofibular fractures in terms of efficacy and complications. To this end, the thesis research can be concluded as follows: Taylor three-dimensional external fixation in the treatment of tibiofibular fractures is more effective, and the incidence of occurrence is low, is a new technology for the treatment of tibiofibular fractures, it is worthy of clinical promotion.


Trials ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Ubiratan Cardinalli Adler ◽  
Maristela Schiabel Adler ◽  
Livia Mitchiguian Hotta ◽  
Ana Elisa Madureira Padula ◽  
Amarilys de Toledo Cesar ◽  
...  

Abstract Objectives To investigate the effectiveness and safety of homeopathic medicine Natrum muriaticum (LM2) for mild cases of COVID-19 in Primary Health Care. Trial design A randomized, two-armed (1:1), parallel, placebo-controlled, double-blind, clinical trial is being performed to test the following hypotheses: H0: homeopathic medicines = placebo (null hypothesis) vs. H1: homeopathic medicines ≠ placebo (alternative hypothesis) for mild cases of COVID-19 in Primary Care. Participants Setting: Primary Care of São Carlos – São Paulo – Brazil. One hundred participants aged 18 years or older, with Influenza-like symptoms and a positive RT-PCR for SARS-CoV-2. Willingness to give informed consent and to comply with the study procedures is also required. Exclusion criterium: severe acute respiratory syndrome. Intervention and comparator Homeopathy: 1 globule of Natrum muriaticum LM2 diluted in 20 mL of alcohol 30% and dispensed in a 30 ml bottle. Placebo: 20 mL of alcohol 30% dispensed in a 30 ml bottle. Posology: one drop taken orally every 4 hours (6 doses/day) while there is fever, cough, tiredness, or pain (headache, sore throat, muscle aches, chest pain, etc.) followed by one drop every 6 hours (4 doses/day) until the fourteenth day of use. The bottle of study medication should be submitted to 10 vigorous shakes (succussions) before each dose. Posology may be changed by telemedicine, with no break in blinding. Study medication should be maintained during home isolation. According to the Primary Care protocol, the home isolation period lasts until the 10th day after the appearance of the first symptom, or up to 72 hours without symptoms. Main outcomes The primary endpoint will be time to recovery, defined as the number of days elapsed before all COVID-19 Influenza-like symptoms are recorded as mild or absent during home isolation period. Secondary measures are recovery time for each COVID-19 symptom; score of the scale created for the study (COVID-Simile Scale); medicines used during follow-up; number of days of follow-up; number of visits to emergency services; number of hospitalizations; other symptoms and Adverse Events during home isolation period. Randomisation The study Statistician generated a block randomization list, using a 1:1 ratio of the two groups (denoted as A and B) and a web-based tool (http://www.random.org/lists). Blinding (masking) The clinical investigators, the statistician, the Primary Care teams, the study collaborators, and the participants will remain blinded from the identity of the two treatment groups until the end of the study. Numbers to be randomised (sample size) One hundred participants are planned to be randomized (1:1) to placebo (50) or homeopathy (50). Trial Status Protocol version/date May 21, 2020. Recruitment is ongoing. First participant was recruited/included on June 29,2020. Due to recruitment adaptations to Primary Care changes, the authors anticipate the trial will finish recruiting on April 10, 2021. Trial registration COVID-Simile Study was registered at the University Hospital Medical Information Network (UMIN - https://www.umin.ac.jp/ctr/index.htm) on June 1st, 2020, and the trial start date was June 15, 2020. Unique ID: UMIN000040602. Full protocol The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.


2021 ◽  
pp. 152660282098527
Author(s):  
Jan Stana ◽  
Carlota Fernandes Prendes ◽  
Ramin Banafsche ◽  
Nikolaos Konstantinou ◽  
Barbara Rantner ◽  
...  

Purpose: To demonstrate the feasibility of urgent endovascular treatment of a chronic type A dissection and contained rupture of the false lumen using a noncustomized triple-branched arch endograft, which necessitated reassignment of the branches to the supra-aortic vessels. Case Report:: A 57-year-old patient with a contained rupture of the descending thoracic aorta, in the setting of a chronic type A dissection and a maximum aortic diameter of 85 mm, was converted to endovascular repair after failure of an open surgical approach. A custom-made triple-branched arch endograft designed for another patient was employed, with concomitant occlusion of the false lumen using a Candy Plug occluder. To adjust the graft’s configuration to the patient’s anatomy, the supra-aortic vessels were not assigned to the originally planned branches. The 12-month follow-up angiography demonstrated a satisfactory result. Conclusion: A noncustomized triple-branched arch endograft can be used in an emergency setting to treat chronic type A dissection, reassigning the branches to the supra-aortic vessels as needed.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Marouf Alhalabi ◽  
Mohammed Waleed Alassi ◽  
Kamal Alaa Eddin ◽  
Khaled Cheha

Abstract Background Antibiotic-resistance reduces the efficacy of conventional triple therapy for Helicobacter Pylori infections worldwide, which necessitates using various treatment protocols. We used two protocols, doxycycline-based quadruple regimen and concomitant levofloxacin regimen. The aim was to assess the effectiveness of doxycycline-based quadruple regimen for treating Helicobacter Pylori infections compared with levofloxacin concomitant regimen as empirical first-line therapy based on intention-to-treat (ITT) and per-protocol analyses (PPA) in Syrian population. Settings and design An open-label, randomised, parallel, superiority clinical trial. Methods We randomly assigned 78 naïve patients who tested positive for Helicobacter Pylori gastric infection, with a 1:1 ratio to (D-group) which received (bismuth subsalicylate 524 mg four times daily, doxycycline 100 mg, tinidazole 500 mg, and esomeprazole 20 mg, each twice per day for 2 weeks), or (L-group) which received (levofloxacin 500 mg daily, tinidazole 500 mg, amoxicillin 1000 mg, and esomeprazole 20 mg each twice per day for two weeks). We confirmed Helicobacter Pylori eradication by stool antigen test 8 weeks after completing the treatment. Results Thirty-nine patients were allocated in each group. In the D-group, 38 patients completed the follow-up, 30 patients were cured. While in the L-group, 39 completed the follow-up, 32patients were cured. According to ITT, the eradication rates were 76.92%, and 82.05%, for the D-group and L-group respectively. Odds ratio with 95% confidence interval was 1.371 [0.454–4.146]. According to PPA, the eradication rates were 78.9%, and 82.05% for the D-group and L-group respectively. The odds ratio with 95% confidence interval was 1.219 [0.394–3.774]. We didn’t report serious adverse effects. Conclusions Levofloxacin concomitant therapy wasn’t superior to doxycycline based quadruple therapy. Further researches are required to identify the optimal first-line treatment for Helicobacter-Pylori Infection in the Syrian population. Trial registration We registered this study as a standard randomized clinical trial (Clinicaltrial.gov, identifier-NCT04348786, date:29-January-2020).


2020 ◽  
Vol 20 (4) ◽  
pp. 801-807
Author(s):  
Lars Arendt-Nielsen ◽  
Jesper Bie Larsen ◽  
Stine Rasmussen ◽  
Malene Krogh ◽  
Laura Borg ◽  
...  

AbstractBackground and aimsIn recent years, focus on assessing descending pain modulation or conditioning pain modulation (CPM) has emerged in patients with chronic pain. This requires reliable and simple to use bed-side tools to be applied in the clinic. The aim of the present pilot study was to develop and provide proof-of-concept of a simple clinically applicable bed-side tool for assessing CPM.MethodsA group of 26 healthy volunteers participated in the experiment. Pressure pain thresholds (PPT) were assessed as test stimuli from the lower leg before, during and 5 min after delivering the conditioning tonic painful pressure stimulation. The tonic stimulus was delivered for 2 min by a custom-made spring-loaded finger pressure device applying a fixed pressure (2.2 kg) to the index finger nail. The pain intensity provoked by the tonic stimulus was continuously recorded on a 0–10 cm Visual Analog Scale (VAS).ResultsThe median tonic pain stimulus intensity was 6.7 cm (interquartile range: 4.6–8.4 cm) on the 10 cm VAS. The mean PPT increased significantly (P = 0.034) by 55 ± 126 kPa from 518 ± 173 kPa before to 573 ± 228 kPa during conditioning stimulation. When analyzing the individual CPM responses (increases in PPT), a distribution of positive and negative CPM responders was observed with 69% of the individuals classified as positive CPM responders (increased PPTs = anti-nociceptive) and the rest as negative CPM responders (no or decreased PPTs = Pro-nociceptive). This particular responder distribution explains the large variation in the averaged CPM responses observed in many CPM studies. The strongest positive CPM response was an increase of 418 kPa and the strongest negative CPM response was a decrease of 140 kPa.ConclusionsThe present newly developed conditioning pain stimulator provides a simple, applicable tool for routine CPM assessment in clinical practice. Further, reporting averaged CPM effects should be replaced by categorizing volunteers/patients into anti-nociceptive and pro-nociceptive CPM groups.ImplicationsThe finger pressure device provided moderate-to-high pain intensities and was useful for inducing conditioning stimuli. Therefore, the finger pressure device could be a useful bed-side method for measuring CPM in clinical settings with limited time available. Future bed-side studies involving patient populations are warranted to determine the usefulness of the method.


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