Outcome analysis of surgical management of comminuted quadrilateral plate acetabulum fractures

<p class="abstract"><strong>Background:</strong> The acetabular quadrilateral fractures are difficult to treat and ORIF using a spring plate buttressing the quadrilateral surface underneath an iliopectenial plate in a 90-90 construct. The aim of the study was to assess the clinical and radiological outcome, success rate and proportion of the post-operative complications of surgical management of comminuted quadrilateral plate acetabulum fractures after ORIF.</p><p class="abstract"><strong>Methods:</strong> It was a hospital based descriptive type of observational study conducted in the Department of Orthopedics, SMS Medical College. The data collection was done from May 2016 up to June 2018. The sample size was 31 for the study purpose, at 95% confidence limits and 20% relative allowable error.<strong></strong></p><p class="abstract"><strong>Results: </strong>We studied 31 patients of communited quadrilateral plate fractures, who were evaluated preoperatively and optimized. ORIF was performed. The mean blood loss was 450 ml and the mean operating time was 130 minutes. The patients were followed up at 1 year postoperatively where 24 patients had an excellent to good Harris Hip clinical score and 24 patients had an excellent to good Matta radiological score, and both were found to be statistically significant.</p><p><strong>Conclusions:</strong> Comminuted quadrilateral plate fractures of the acetabulum are managed surgically by ORIF using a spring buttressing plate beneath the infrapectenial plate. The clinical and radiological follow up for one year duration scores showed good scores which were statistically significant, indicating the success of quadrilateral fixation using this technique. </p>

Posterior wall acetabular fracture fixation: A mechanical analysis of fixation methods

Stable, anatomical fixation of acetabular fractures gives the best chance of successful outcome, while penetration of the acetabular articular surface with screws is associated with poor outcomes. Spring plates are an alternative to interfragmentary lag screws when penetration is a concern. A mechanical study comparing fracture stability and construct stiffness of three fixation methods for posterior wall acetabular fractures with transverse comminutions was performed. The three fixation methods tested were a posterior wall rim plate, a posterior wall buttress plate with separate lag screws and a posterior wall plate with two spring plates. Nine samples were tested, three for each fixation method. Two-dimensional motion analysis was used to measure fracture fragment displacement and construct stiffness. After two 6000 cycle-loading protocols, to a maximum 1.5 kN, the mean fracture displacement was 0.154 mm for the rim plate model, 0.326 mm for the buttress plate and 0.254 mm for the spring plate model. Mean maximum displacement was significantly less for the rim plate fixation than the buttress plate ( p = 0.015) and spring plate fixation ( p = 0.02). The rim plate was the stiffest construct 10,962 N/mm, followed by the spring plate model 5637 N/mm and the buttress plate model 4882 N/mm. Based on data obtained in this study, where possible a rim plate with interfragmentary lag screws should be used for isolated posterior wall fractures as this is the stiffest and most stable construct. When this method is not possible, spring plate fixation is a safe and a superior alternative to a posterior buttress plate method.

Increasing Labor Efficiency Repairing Metal Structures of Heavy-Duty Quarry Machinery

Supporting metal structures of large dump trucks at open cast coal mines function under exposure to alternating cyclic load. Fatigue cracks that appear there require timely maintenance welding. Organization of repair processes is multivariant; it can be performed either by the enterprise (open cast coal mine) efforts or by special repair units. An industrial experiment carried out at Permyakovskiy and Prokopyevskiy open cast coal mines in Kuzbass has shown that type of large dump trucks’ repair works organization influences significantly process efficiency. Repair welding by enterprise efforts is the most non-productive compared to other types of repair process organization. Its specific rate is 37 per cent lower than in comparison with unstructured welding and 2.2 times lower in comparison with structured metal sheet replacement and structured welding. Structuring repair processes allows to increase their efficiency by 30...40 per cent on average. Structured replacement of the spring plate is the most productive type of metal structure repair process organization. Comparison of maintenance measurement results in accordance with Unified Norms and Prices collected book with the results obtained from the industrial experiment showed that calculation methods give underestimated values of repair processes’ specific rate.

A Novel Gripper design for Diaphragm spring plate Pick and Place Cobot

Robot integrated manufacturing has turned out to be the future of manufacturing automation technology. Worker assisting robots perform simultaneously operation including machining, assembly, inspection, material handling etc. and in some case multiple operations in the same system at a faster and precise rate. Collaborative robots are human and computer controlled hybrid material handling device which facilitates the concept of shared workspace. To exploit its function, gripper mechanisms are inevitable. This project focuses on the design of cobotic grippers for pick and place application. Of the different concepts compared a suitable design is chosen. The gripper moves according to the signals received from the cobot, sensors and PLC control system.

Lightweight Design of Absorber Spring Plate Based on Topological Optimization Method

HyperMesh was used to mesh the absorber spring plate, and MATLAB was used to read-in grid node coordinate file and to carry on multi-target structure topological optimization design through the self-compiled program. Objective functions include rigidity, volume and fatigue life etc. model reconstitution, CAE analysis and experimental verification were completed according to the optimization result. Results showed that optimized spring plate met the using need and lightweight design was accomplished.