Search results for "Prosthesis Failure"
showing 10 items of 41 documents
The effect of surgical suture material on osteoclast generation and implant-loosening
2020
Background: Implant loosening - either infectious or aseptic- is a still a major complication in the field of orthopaedic surgery. In both cases, a pro-inflammatory peri-prosthetic environment is generated by the immune system - either triggered by bacteria or by implant wear particles - which leads to osteoclast differentiation and osteolysis. Since infectious cases in particular often require multiple revision surgeries, we wondered whether commonly used surgical suture material may also activate the immune system and thus contribute to loss of bone substance by generation of osteoclasts. Methods: Tissue samples from patients suffering from infectious implant loosening were collected intr…
Management of Cochlear Implant Electrode Migration.
2016
The present study reviewed a cochlear implant (CI) patient population after surgery, which received a free-fitting electrode carrier designed for hearing preservation. The aim was to determine the rate of electrode migration of the CI electrodes and present clinical and surgical implications.Retrospective patient review.Tertiary referral university hospital.Two hundred seventy-eight patients implanted uni- or bilaterally with lateral wall electrodes designed for hearing preservation (358 implants). The control group was 323 patients implanted uni- or bilaterally with preformed perimodiolar electrodes (468 implants).Determination of CI electrode migration was conducted according to a clinica…
Reoperation Rates Following Instrumented Lumbar Spine Fusion
2018
Study Design. A prospective cohort study. Objective. This study evaluated the cumulative reoperation rate and indications for reoperation following instrumented lumbar spine fusion (LSF). Summary of Background Data. LSF reduces disability and improves health-related quality of life for patients with several spinal disorders. The rate of instrumented LSF has drastically increased over the last few decades. The increased incidence of LSF, however, has led to increased reoperation rates. Methods. The data are based on the prospective LSF database of Tampere University Hospital that includes all elective indications for LSF surgery. A total of 433 consecutive patients (64% women, mean age 62 ye…
CD3+ lymphocytosis in the peri-implant membrane of 222 loosened joint endoprostheses depends on the tribological pairing.
2017
Background and purpose — The most frequent cause of arthroplasty failure is aseptic loosening—often induced by particles. Abrasion material triggers inflammatory reactions with lymphocytic infiltration and the formation of synovial-like interface membranes (SLIM) in the bone–implant interface. We analyzed CD3 quantities in SLIM depending on articulating materials and possible influences of proven material allergies on CD3 quantities. Patients and methods — 222 SLIM probes were obtained from revision surgeries of loosened hip and knee arthroplasties. SLIM cases were categorized according to the SLIM-consensus classification and to the particle algorithm. The CD3 quantities were analyzed immu…
Metastatic instability at the proximal end of the femur
1994
A retrospective study was performed of the surgical treatment of metastatic lesions of the proximal femur in 50 patients. In 25 consecutive cases a megaprosthesis was implanted; compound plate osteosynthesis was performed in another 25 consecutive patients. Indications for surgical treatment were pathological fractures or, for prophylactic treatment, lesions of the femoral cortex exceeding 2.5 cm in diameter or affecting half the diameter of the bone or more. In all patients capable of walking preoperatively mobility was regained. Immediate full weight-bearing stability was obtained in all patients. Group analysis showed that the functional rating of the hip joint was unchanged, i.e., good …
Long-term results of the use of silicone sheets after diskectomy in the temporomandibular joint: clinical, radiographic and histopathologic findings
1999
The aim of the present study was to evaluate the long-term results of a group of patients who had the disk of the temporomandibular joint (TMJ) removed and permanently replaced by a silicone sheet. The study group comprised 48 patients, treated in the period from 1983 to 1993. In eight patients, the implants had to be removed after an average interval of 5.6 years and they were submitted for histopathological examination. Twenty-five of the 40 patients with silastic implants in place, and five of the 8 patients who had their implants removed, were available for long-term follow-up (mean interval of 7.0 years, SD 2.8 years). Clinical function was rated according to the Helkimo Dysfunction In…
Analysis of Fifty-Six Cochlear Implant Device Failures
2008
<i>Objective:</i> Our aim was to present a failure analysis after cochlear implant revision surgery in a large series of children and adults and to assess the outcome and audiologic performance. <i>Methods:</i> Fifty-six cochlear implant failures that occurred in 422 devices implanted between 1990 and 2007 at the Department of Otolaryngology, Head and Neck Surgery at the University of Mainz, Germany, were retrospectively analyzed. The causes of failure were reviewed evaluating the individual history, telemetric and intraoperative findings and manufacturer’s investigation reports. <i>Results:</i> We performed 56 surgical revisions in a series of 422 consec…
Complications of Poly Implant Prothèse breast implants: the current discussion
2013
Against the background of the current discussion about Poly Implant Prothèse (PIP, Seyne-sur-mer, France) breast implants, we want to present a case demonstrating the complications such as implant rupture, silicone dissemination and level III silicone lymphadenopathy. A 29-year-old woman with cosmetic breast augmentation with PIP implants 5 years previously showed a sensitive swelling in her right axilla and neck region. All tests to detect an infectious or lymphomatous lymphadenopathy were negative. After ultrasound and MRI, rupture of the right implant was assumed and multiple pathologically enlarged lymph nodes up to supraclavicular region were shown. An excision biopsy of one axillary l…
Computer Modeling for the Prediction of Thoracic Aortic Stent Graft Collapse
2011
OBJECTIVE: To assess the biomechanical implications of excessive stent protrusion into the aortic arch in relation to thoracic aortic stent graft (TASG) collapse by simulating the structural load and quantifying the fluid dynamics on the TASG wall protrusion extended into a model arch. METHODS: One-way coupled fluid-solid interaction analyses were performed to investigate the flow-induced hemodynamic and structural loads exerted on the proximal protrusion of the TASG and aortic wall reconstructed from a patient who underwent traumatic thoracic aortic injury repair. Mechanical properties of a Gore TAG thoracic endoprosthesis (W. L. Gore and Assoc, Flagstaff, Ariz) were assessed via experimen…
An In Vitro Phantom Study on the Role of the Bird-Beak Configuration in Endograft Infolding in the Aortic Arch.
2015
Purpose: To assess endograft infolding for excessive bird-beak configurations in the aortic arch in relation to hemodynamic variables by quantifying device displacement and rotation of oversized stent-grafts deployed in a phantom model. Methods: A patient-specific, compliant, phantom pulsatile flow model was reconstructed from a patient who presented with collapse of a Gore TAG thoracic endoprosthesis. Device infolding was measured under different flow and pressure conditions for 3 protrusion extensions (13, 19, and 24 mm) of the bird-beak configuration resulting from 2 TAG endografts with oversizing of 11% and 45%, respectively. Results: The bird-beak configuration with the greatest protr…