scholarly journals Three-Dimensional Digital Surgical Planning and Rapid Prototyped Surgical Guides in Bernese Periacetabular Osteotomy

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Bruno Gonçalves Schröder e Souza ◽  
Flavia de Souza Bastos ◽  
Valdeci Manoel de Oliveira ◽  
Alfredo Chaoubah
Keyword(s):  
Periacetabular Osteotomy ◽  
Three Dimensional ◽  
Developmental Dysplasia ◽  
Production Costs ◽  
Steep Learning Curve ◽  
Safety Issues ◽  
Surgical Guides ◽  
Early Results ◽  
Planning Guide ◽  
Pao Surgery

Bernese periacetabular osteotomy (PAO) developed by Ganz is currently the treatment of choice for skeletally mature symptomatic patients with developmental dysplasia of the hip (DDH) without osteoarthritis. However, the steep learning curve and considerable number of severe complications lead surgeons to seek for alternatives to promote greater reproducibility and safety of this procedure. This is a report of a DDH case surgically treated with the aid of a digital three-dimensional (3D) planning and rapidly prototyped sterile ABS plastic osteotomy guide, developed in Brazil. We present details regarding the planning, guide production, and surgical technique and report the early results of this treatment approach in a single patient. Digital 3D planning and rapidly prototyped surgical guides are applicable and helpful in PAO surgery as shown in this case. We noted no safety issues, good accuracy, and low production costs with this approach.

scholarly journals Periacetabular Osteotomy Performed with Imageless Computer-Assisted Navigation: Case Report

2019 ◽  
Vol 2 (1-3) ◽  
pp. 33-39
Author(s):  
Atul F. Kamath ◽  
Rachel R. Mays
Keyword(s):  
Surgical Navigation ◽  
Periacetabular Osteotomy ◽  
Computer Navigation ◽  
Developmental Dysplasia ◽  
Computer Assisted ◽  
Developmental Hip Dysplasia ◽  
Assisted Navigation ◽  
First Case ◽  
Acetabular Fragment ◽  
Pao Surgery

Periacetabular osteotomy (PAO) is an effective surgical treatment for developmental hip dysplasia. The goal of PAO is to reorient the acetabulum to increase acetabular coverage of the femoral head, as well as to reduce contact pressures within the hip joint. The primary challenge of PAO is to accurately achieve the desired acetabular fragment orientation, while maximizing containment and congruency. As key parts of the procedure are performed out of direct field of view of the surgeon, combined with this challenge of precise spatial orientation, there is a potential role for technologies such as surgical navigation. Adjunctive technology may provide information on the orientation of repositioned acetabulum and may offer a useful assist in performing PAO. Here, we present a case of developmental dysplasia of the hip treated via PAO with the addition of an imageless computer navigation device. Surgery was successful, and, at 3 months after procedure, the patient was progressing well. To our best knowledge, this is the first case using imageless computer-assisted navigation in PAO surgery.

Guided surgery with 3D printed device: a case report

2020 ◽  
Author(s):  
Michelle Carvalho de Sales ◽  
Rafael Maluza Flores ◽  
Julianny da Silva Guimaraes ◽  
Gustavo Vargas da Silva Salomao ◽  
Tamara Kerber Tedesco ◽  
...  
Keyword(s):  
Operating Time ◽  
Three Dimensional ◽  
Conventional Technique ◽  
Cervical Region ◽  
Mean Deviation ◽  
Apical Region ◽  
Virtual Planning ◽  
Surgical Guide ◽  
Surgical Guides ◽  
High Level

Dental surgeons need in-depth knowledge of the bone tissue status and gingival morphology of atrophic maxillae. The aim of this study is to describe preoperative virtual planning of placement of five implants and to compare the plan with the actual surgical results. Three-dimensional planning of rehabilitation using software programs enables surgical guides to be specially designed for the implant site and manufactured using 3D printing. A patient with five teeth missing was selected for this study. The patient’s maxillary region was scanned with CBCT and a cast model was produced. After virtual planning using ImplantViewer, five implants were placed using a printed surgical guide. Two weeks after the surgical procedure, the patient underwent another CBCT scan of the maxilla. Statistically significant differences were detected between the virtually planned positions and the actual positions of the implants, with a mean deviation of 0.36 mm in the cervical region and 0.7 mm in the apical region. The surgical technique used enables more accurate procedures when compared to the conventional technique. Implants can be better positioned, with a high level of predictability, reducing both operating time and patient discomfort.

scholarly journals BORDERLINE ACETABULAR DYSPLASIA: THREE-DIMENSIONAL DEFORMITY PREDICTORS OF THE DIAGNOSIS OF SYMPTOMATIC INSTABILITY TREATED WITH PERIACETABULAR OSTEOTOMY

2021 ◽  
Vol 9 (7_suppl3) ◽  
pp. 2325967121S0016
Author(s):  
Elizabeth Graesser ◽  
Maria Schwabe ◽  
Cecilia Pascual Garrido ◽  
John C. Clohisy ◽  
Jeffrey J. Nepple
Keyword(s):  
Low Dose ◽  
Acetabular Dysplasia ◽  
Periacetabular Osteotomy ◽  
Alpha Angle ◽  
Three Dimensional ◽  
Acetabular Coverage ◽  
Low Dose Ct ◽  
Femoral Version ◽  
Center Edge ◽  
Hip Morphology

Introduction: Borderline acetabular dysplasia is classically defined as a lateral center edge angle (LCEA) of 20-25 degrees. The optimal treatment strategy in this patient group remains controversial, with some patients having primarily hip instability-based symptoms, while others have primarily impingement-based symptoms (non-instability). The purpose of the current study was to define the 3D characteristics on low-dose CT that differentiate patients with instability symptoms from those without instability in the setting of borderline acetabular dysplasia. Methods: Seventy consecutive hips with borderline acetabular dysplasia undergoing surgical treatment were included in the current study. All patients underwent low-dose pelvic CT with femoral version assessment for preoperative planning. CT measurements included alpha angle and radial acetabular coverage (RAC) at standardized clockface positions (9:00-posterior to 3:00-anterior), central and cranial acetabular version. RAC was assessed in three sectors (anterior, superior, and posterior) and defined (relative to published normative data) as normal (-1 SD, +1 SD), undercoverage (<-1 SD), or overcoverage (>+1 SD). Statistical analysis was performed to compare the CT characteristics of the symptomatic instability and non-instability groups. Results: Of the 70 hips, 62.9% had the diagnosis of symptomatic instability, while 37.1% had no instability symptoms. Hips with instability (compared to non-instability) had significantly lower alpha angle (maximal difference at 1:00 - 47.0° vs. 59.4°), increased femoral version (22.3° vs. 15.3°), and decreased radial acetabular coverage (maximal difference at 1:00 – 59.9% vs. 62.2%) (all p<0.001). Multivariate analysis identified femoral version (OR 1.1, p=0.02), alpha angle at 1:00 (OR 0.91, p=0.02), and RAC at 1:00 (OR 0.46, p=0.003) as independent predictors of the presence of instability. The model combining these three factors had excellent predictive probability with a c-statistic 0.92. Conclusion: We found significant differences in the 3D hip morphology of the symptomatic instability and non-instability subgroups within the borderline dysplasia cohort. In the setting of borderline dysplasia, three-dimensional deformity characterization with low-dose CT allowed for differentiation of patients diagnosed with underlying instability vs. non-instability. Femoral version, alpha angle at 1:00, and radial acetabular coverage at 1:00 were identified as independent predictors of diagnosis in borderline acetabular dysplasia. Summary: This study attempts to define 3D CT characteristics to help distinguish between patients with impingement-based vs instability-based symptoms of borderline acetabular dysplasia.

Weight-Reduction Optimization Design for Milling Planer Bed Based on Finite Element Analysis

2012 ◽  
Vol 490-495 ◽  
pp. 2785-2789
Author(s):  
Dong Sun ◽  
Xu Dong Yang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Weight Reduction ◽  
Optimization Design ◽  
Weak Link ◽  
Three Dimensional ◽  
Production Costs ◽  
Element Analysis ◽  
Before And After ◽  
Improvement Scheme

The milling planer bed is one of the most important foundational parts for the entire machine, sufficient stiffness is required. The posterior segment of a certain milling planer bed is regarded as the optimization object in this paper. Three-dimensional modeling method is used to calculate the exact weight of the bed and then finite element analysis is used to research the static and dynamic characteristics before and after weight-reduction. The weak link of the bed is found out and a improvement scheme is put forward ensuring lower production costs under the premise of sufficient rigidity.

Modeling and Simulation of Optimal Blank Design and Hot Pressing Process for Manufacturing Large Francis Turbines Blades From Very Thick Plates

2013 ◽  
Author(s):  
Zhengkun Feng ◽  
Henri Champliaud ◽  
Louis Mathieu ◽  
Michel Sabourin
Keyword(s):  
Hot Pressing ◽  
Three Dimensional ◽  
High Strength ◽  
Production Costs ◽  
Francis Turbine ◽  
Thick Plates ◽  
Pressing Process ◽  
Blank Design ◽  
Cost Of Energy ◽  
Applied Forces

Hot pressing process is widely used in automotive, shipbuilding, energy production and civil engineering. However, the trial and error technique that is intensive time and energy consuming is still used. Particularly, the design of Francis turbines of hydropower plants is not standard, but variable from site to site due to hydraulic conditions and cost of energy. As a result, the blade hydraulic profile of each Francis turbine is different. The blades, one of the key components of Francis turbine runners, are produced in small batches and the setup of the dedicated punch and die increases significantly the unit production costs. In this paper, the blade unfolding process for optimal blank design will be firstly presented, and then a hot pressing process for very thick plates is proposed. The pressing process of high strength steel at hot temperature is characterized by thermo-mechanical behaviors, three-dimensional unsteady deformation, high nonlinearity, continuous local forming. The analyses of residual stress distribution and applied forces are carried out.

scholarly journals Residual hip dysplasia: is there a place for hip shelf operation?

2018 ◽  
Vol 12 (4) ◽  
pp. 358-363 ◽  
Author(s):  
T. Terjesen
Keyword(s):  
Periacetabular Osteotomy ◽  
Developmental Dysplasia ◽  
Hip Pain ◽  
Older Children ◽  
Long Term Effects ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Shelf Procedure ◽  
Shelf Operation

Purpose After modern acetabular osteotomies were introduced, hip shelf operations have become much less commonly used. The aims of this study were to assess the short-term and long-term outcome of a modified Spitzy shelf procedure and to compare the results with those of periacetabular osteotomy (PAO). Methods In all, 44 patients (55 hips) with developmental dysplasia of the hip and residual dysplasia had a modified Spitzy shelf operation. Mean age at surgery was 13.2 years (8 to 22). Indication for surgery was a centre-edge angle < 20° with or without hip pain. Outcome was evaluated using duration of painless period and survival analysis with conversion to total hip arthroplasty (THA) as endpoints. Results Preoperative hip pain was present in 46% of the hips and was more common in patients ≥ 12 years at surgery (p < 0.001). One year postoperatively, 93% of the hips were painless. Analysis of pain in hips with more than ten years follow-up showed a mean postoperative painless period of 20.0 years (0 to 49). In all, 44 hips (80%) had undergone THA at a mean patient age of 50.5 years (37 to 63). Mean survival of the shelf procedure (time from operation to THA) was 39.3 years (21 to 55). Conclusions The Spitzy operation had good short and long-term effects on hip pain and a 30-year survival (no THA) of 72% of the hips. These results compare favourably with those of PAO and indicate that there is still a place for the shelf procedure in older children and young adults.

scholarly journals Implementing a 3D printing service in a biomedical library

2017 ◽  
Vol 105 (1) ◽  
Author(s):  
Verma Walker, MLIS
Keyword(s):  
Problem Solving ◽  
3D Printing ◽  
3D Modeling ◽  
Three Dimensional ◽  
National Institutes Of Health ◽  
3D Printer ◽  
Service Model ◽  
Steep Learning Curve ◽  
3D Printers ◽  
Creative Problem

Three-dimensional (3D) printing is opening new opportunities in biomedicine by enabling creative problem solving, faster prototyping of ideas, advances in tissue engineering, and customized patient solutions. The National Institutes of Health (NIH) Library purchased a Makerbot Replicator 2 3D printer to give scientists a chance to try out this technology. To launch the service, the library offered training, conducted a survey on service model preferences, and tracked usage and class attendance. 3D printing was very popular, with new lab equipment prototypes being the most common model type. Most survey respondents indicated they would use the service again and be willing to pay for models. There was high interest in training for 3D modeling, which has a steep learning curve. 3D printers also require significant care and repairs. NIH scientists are using 3D printing to improve their research, and it is opening new avenues for problem solving in labs. Several scientists found the 3D printer so helpful they bought one for their labs. Having a printer in a central and open location like a library can help scientists, doctors, and students learn how to use this technology in their work.

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