Anatomic metal back

PURPOSE: The purpose of our study was to evaluate the clinical and radiological results of a new anatomic convertible cementless glenoid component. METHODS: Forty-eight patients with a mean age of 67.3 years were clinically and radiologically followed-up with a mean of 49 months. Indications for glenoid replacement were A2 glenoid wear in 21.7%, B1 glenoid wear in 28.3%, B2 glenoid wear in 28.3%, B3 glenoid wear in 13%, D glenoid wear in 2.2%, and glenoid component loosening in 6...

BACKGROUND: An important reason for failure of anatomic total shoulder arthroplasty is glenoid component loosening. We investigated the effect of backside bone support on the risk of failure of a glenoid component. METHODS: A finite element model was developed. Virtual surgery was performed for 2 types of glenoid components (cemented all polyethylene [PE] vs. metal backed [MB]), both with gradually decreasing backside bone support. Both bone failure and fixation failure were analyzed...

Metal artifact reduction (MAR) algorithms reduce the errors caused by metal implants in xray computed tomography (CT) images and are an important part of error management in radiotherapy (RT). A promising MAR approach is to leverage the information in magnetic resonance (MR) images that are acquired for organ or tumor delineation. This is however complicated by the ambiguous relationship between CT values and conventional-sequence MR intensities as well as potential co-registration issues. In order to address these issues, this paper proposes a self-tuning Bayesian model for MR-based MAR that combines knowledge of the MR image intensities in local spatial neighborhoods with the information in an initial, corrupted CT reconstructed using filtered back projection...

Changes in joint architecture and muscle loading resulting from total shoulder arthroplasty (TSA) and reverse total shoulder arthroplasty (RSA) are known to influence joint stability and prosthesis survivorship. This study aimed to measure changes in muscle moment arms, muscle lines of action, as well as muscle and joint loading following TSA and RSA using a metal-backed uncemented modular shoulder prosthesis. Eight cadaveric upper extremities were assessed using a customized testing rig. Abduction, flexion, and axial rotation muscle moment arms were quantified using the tendon-excursion method, and muscle line-of-force directions evaluated radiographically pre-operatively, and after TSA and revision RSA...

Anatomic total shoulder arthroplasty (TSR) has been shown to generate good to excellent results for patients with osteoarthritis and a functioning rotator cuff. Many studies have reported that the glenoid component loosening and failure remain the most common long-term complication of total shoulder arthroplasty. The approach to glenoid component is critical because a surgeon should consider patient-specific anatomy, preserving bone stock and joint line restoration, for a good and durable shoulder function...

To evaluate iterative metal artifact reduction (iMAR) technique in images data of hip prosthesis on computed tomography (CT) and the added value of advanced modeled iterative reconstruction (ADMIRE) compared with standard filtered back projection (FBP).Twenty-eight patients addressed to CT examinations for hip prosthesis were included prospectively. Images were reconstructed with iMAR algorithm in addition to FBP and ADMIRE techniques. Measuring image noise assessed objective image quality and attenuation values with standardized region of interest (ROI) in 4 predefined anatomical structures (gluteus medius and rectus femoris muscles, inferior and anterior abdominal fat, and femoral vessels when contrast media was present)...

AIMS: We present our experience of using a metal-backed prosthesis and autologous bone graft to treat gross glenoid bone deficiency. PATIENTS AND METHODS: A prospective cohort study of the first 45 shoulder arthroplasties using the SMR Axioma Trabecular Titanium (TT) metal-backed glenoid with autologous bone graft. Between May 2013 and December 2014, 45 shoulder arthroplasties were carried out in 44 patients with a mean age of 64 years (35 to 89). The indications were 23 complex primary arthroplasties, 12 to revise a hemiarthroplasty or resurfacing, five for aseptic loosening of the glenoid, and five for infection...

BACKGROUND: Rotator cuff tears following anatomic total shoulder arthroplasty increase with duration of follow-up. This study aimed to evaluate contact pressure between the rotator cuff tendons and prosthesis after anatomic total shoulder arthroplasty and compare these with the tendon-contact pressures in the native shoulder. METHODS: Eight entire upper extremities were mounted onto a testing apparatus, and simulated muscle loading was applied to each rotator cuff tendon with the shoulder positioned in abduction, internal rotation, and external rotation...

AIMS: Controversy about the use of an anatomical total shoulder arthroplasty (aTSA) in young arthritic patients relates to which is the ideal form of fixation for the glenoid component: cemented or cementless. This study aimed to evaluate implant survival of aTSA when used in patients aged < 60 years with primary glenohumeral osteoarthritis (OA), and to compare the survival of cemented all-polyethylene and cementless metal-backed glenoid components. MATERIALS AND METHODS: A total of 69 consecutive aTSAs were performed in 67 patients aged < 60 years with primary glenohumeral OA...

IMPLANT DESIGNS: Within the last 50 years, implants for shoulder replacement have developed rapidly. Monobloc-stems in few sizes were changed to modular implant systems that allow for an individual adaption of the stem, as well as adaption of the humeral head component according to the specific anatomic situation of the patient. Moreover, stemless und short stem implants are available, which may highly simplify primary implantation, especially in posttraumatic cases as well as in revision cases with a need for removal or change of the implants...

BACKGROUND: As glenoid failure is one of the primary causes of failure of anatomic total shoulder arthroplasty (TSA), Trabecular Metal-backed glenoid components have become popular. This study reports implant survival and clinical outcomes of patients who received a Trabecular Metal-backed glenoid component during primary anatomic TSA. METHODS: Patients who underwent TSA with a Trabecular Metal-backed glenoid component by a single surgeon were identified and reviewed for clinical, radiographic, and patient-reported outcome measures with a minimum of 2 years' follow-up...

BACKGROUND: Glenoid component failure is a prevalent mechanical complication of anatomic total shoulder arthroplasty. The objective of this study was to identify surgeon-controlled factors that may be addressed to reduce the rate of glenoid component failure that is sufficiently symptomatic to merit surgical revision. METHODS: We reviewed the clinical and radiographic features of 215 total shoulder arthroplasties that we revised for symptomatic glenoid component failure...

Background: Dental hardware produces streak artifacts on computed tomography (CT) images reconstructed with the standard weighted filtered back projection (wFBP) method. Purpose: To perform a preliminary evaluation of an iterative metal artifact reduction (IMAR) technique to assess its ability to improve anatomic visualization over wFBP in patients with dental amalgam or other hardware. Material and Methods: CT images from patients with dental hardware were reconstructed using wFBP and IMAR software and soft-tissue or bone window/level settings...

AIM: To evaluate the joint geometry and the clinical outcome of stemless, anatomical shoulder arthroplasty with the TESS system. METHODS: Twenty-one shoulders with a mean follow-up 18 of months were included. On scaled digital radiographs the premorbid center of rotation (CoR) was assessed and compared to the CoR of the prosthesis by using the MediCAD® software. Additionally, the pre- and post-operative geometry of the CoR was assessed in relation to the glenoid, the acromion as well as to the proximal humerus...

BACKGROUND: The quality of CT slices can be drastically reduced in the presence of high-density objects such as metal implants within the patients' body due to the occurrence of streaking artifacts. Consequently, a delineation of anatomical structures might not be possible, which strongly influences clinical examination. PURPOSE: The aim of the study is to clinically evaluate the retrieval of attenuation values and structures by the recently proposed Augmented Likelihood Image Reconstruction (ALIR) and linear interpolation in the presence of metal artifacts...

BACKGROUND: Instability is one of the major causes of failures in unconstrained anatomic total shoulder arthroplasty (TSA). This study reviewed the instabilities that may occur in an anatomic shoulder platform system to identify its potential predictors. We hypothesized that soft tissue deficiency was the main cause of instability and that the best treatment option would be conversion to a reverse shoulder arthroplasty (RSA). MATERIALS AND METHODS: Between 2003 and 2013, we reviewed 27 patients who experienced postoperative instability, and the overall incidence was 5...

AIM: To investigate the value of dedicated computed tomography (CT) iterative metal artefact reduction (iMAR) algorithms in patients after spinal instrumentation. MATERIALS AND METHODS: Post-surgical spinal CT images of 24 patients performed between March 2015 and July 2016 were retrospectively included. Images were reconstructed with standard weighted filtered back projection (WFBP) and with two dedicated iMAR algorithms (iMAR-Algo1, adjusted to spinal instrumentations and iMAR-Algo2, adjusted to large metallic hip implants) using a medium smooth kernel (B30f) and a sharp kernel (B70f)...

PURPOSE: To optimize the cesium iodide (CsI:Tl) scintillator thickness in a complimentary metal-oxide semiconductor (CMOS)-based detector for use in dedicated cone-beam breast CT. METHODS: The imaging task considered was the detection of a microcalcification cluster comprising six 220µm diameter calcium carbonate spheres, arranged in the form of a regular pentagon with 2 mm spacing on its sides and a central calcification, similar to that in ACR-recommended mammography accreditation phantom, at a mean glandular dose of 4...

We report on two cases in which Y-shaped coronary bifurcations were treated with the use of Bioresorbable scaffolds. The first case was of a 50-year-old man with NSTEMI. Coronary angiography showed stenosis involving a Y-shaped bifurcation of proximal to mid LAD and diagonal. The lesion was wired using two 0.14 BMW guide wires, followed by serial pre-dilatation of LAD and Diagonal branch. The stent into proximal LAD was deployed first as a skirt (3.5 × 12 BVS). Stent was post-dilated. A second 2.5 × 28 BVS was deployed into diagonal branch, protruding backwards; along with a 2...

BACKGROUND AND PURPOSE: Slice-Encoding Metal Artifact Correction (SEMAC) sequence is one of the metal artifact reduction techniques of anatomical structure, but there has been no report about evaluation of post-operative complications. The purpose of this article is to compare the anatomical visibility between fast spin echo (FSE) and FSE-SEMAC and to evaluate the additional value of FSE-SEMAC in diagnostic confidence of the complications. MATERIALS AND METHODS: We conducted a retrospective study with 54 patients who received lumbar spinal surgery and MR images including FSE-SEMAC...