Design And Finite Element Analysis Of The Scapula Anatomic Plate

Scapula fractures are Desault first described in1805,1937Findlay reported37cases of fracture of the scapula, first described the scapular fracture characteristics.Hardegger1984was noted that scapular fractures account for1%of body fractures,accounting for5%of the entire shoulder fracture. Scapula fractures are usuallycaused by a high-energy trauma, such as car accident injuries, falls. To youngmales, accounting for64%to90%. The low-energy injury scapula fracture, asavulsion fractures and overuse injuries (fatigue damage) rare. Scapular fracturesoften as part of multiple injuries, often ignored or omissions. With the socialdevelopment, science and technology as well as transport undertakings developed,its incidence is gradually increasing. Scapular fracture combined with history,physical examination and X-ray or CT scan can confirm the diagnosis in general.Treatment of scapular fractures more, there are non-surgical treatment andsurgical treatment two blocks, each also contains a variety of treatments, previousliterature also reported more, but so far there is no conclusive data on the variousmethods which is better or wrongly. For the treatment of scapular fractures and hasaccumulated a certain amount of research data, but little information on the clinicalstudy, needs further discussion. Currently advocate for different types of scapularfractures should take different approaches to treatment, try to make individualized.Whether surgery or non-surgical treatment, its therapeutic purposes are shoulderfunctional recovery and prevent complications. The surgical treatment of scapularfractures currently most focused on the glenoid neck, this site involves the articular surface, requiring as much as possible anatomic, otherwise postoperative joint pain,instability, such as a higher incidence of complications impact. The fixtures in thescapular fracture types are more common calcaneal plate, reconstruction plate, T, Yplate, absorbed nails, cannulated screws or micro-plates, anchors, steel and otherfixed, of which the most widely reconstruction plates. Multiple internal fixationmaterials above to be fixed before shaping, complicated operation, prolongedoperative time, after shaping the fracture surfaces are not completely fit clothing,shaping and bending stability will have a material impact. Due to rapid economicdevelopment in recent years, high-energy trauma traffic accident-prone, scapulafractures were increasing, and the patient required surgical treatment significantlyimproved the traditional fixation material due to its limitations have been unable tomeet its requirements. It should have its exclusive anatomical shoulder blade steelplates to avoid surgery on pre-bend, reducing surgery time, reduce blood loss. Theuse of anatomical plate for fixation of the scapula fractures occur, anatomicreduction, rigid fixation, early postoperative functional exercise can reducepostoperative pain, shock, instability and other complications.In recent years, with the computer image processing, increasing development ofdigital technology and sophisticated, three-dimensional simulation and finiteelement analysis method is also increasingly used in various fields, which greatlypromoted the development of the biomedical field. Especially as orthopedicbiomechanics research, more than usual limited biomechanical analysis of cadavers,and the emergence of three-dimensional finite element simulation provides newmethods and tools for the study of biomechanics, it also allows us to put forwardthe results of previous experiments a new view. Design common internal fixationdevices, rehabilitation equipment and other medical devices are based on bonestress and strain as the basis for, and the application of finite element analysistechnology for more accurate three-dimensional human bones were fast simulationand data analysis calculations, scientific medical devices designed to provide apowerful tool.The study on the clinical response to these problems, according to the characteristics of the anatomy of the scapula scapular anatomical plate design,combined with three-dimensional finite element analysis method, from the point ofview of the mechanics of the scapula independent design and general reconstructionof anatomical plate steel used in complex fractures of the scapula correlationanalysis and comparison of mechanical properties and explore its clinicalbiomechanical significance.Objective1. Design scapula anatomic plate;2. The establishment of a three-dimensional finite element model of thescapula;3. A three-dimensional model of the scapula conducted under different loadsmechanical analysis;4. Comminuted fracture of the scapula build three-dimensional finite elementmodel and simulate the application of the scapula and the general reconstruction ofanatomical plate steel plate fracture fixation, on both a comparative analysis of thebiomechanical stability.Methods1. According to the scapula specimen morphology and related entitiesradiological measurements, combined with relevant literature, anatomical dataobtained scapula, shoulder blade designed anatomical plate.2. Use the scapula dimensional tomographic CT data continuously throughMimics10.01software, Solidworks2010software to build three-dimensional finiteelement model of the scapula, shoulder blade and analyze simple stress and straindistribution. And in accordance with previous results reported in the literature andclinical phenomena observed on the model validation.3. For six healthy adult volunteers spiral CT scans scapula and associatedmodeling software built by comminuted fracture of the scapula and shoulder bladeplate fixation with reconstruction plate fixation anatomical dimensional finiteelement model to simulate the lateral, vertical, anteroposterior direction external load hit three conditions, evaluation of maximum stress steel under variousconditions, the largest integrated displacement fracture block.4. On the basis of the previous model, for both the fixed maximum equivalentstress, displacement of the fracture fragments of the largest comprehensiveevaluation to explore the rationality and feasibility of practical application of thenew scapula anatomical plate design.Results:1. A successful design scapula anatomical plate, and has applied for patent.2. Scapula dimensional finite element model established through comparisonwith traditional biomechanical experiments and clinical observations phenomenon,combined with relevant literature, proved to be effective and reasonable.3. Construction of anatomical plates and general reconstruction plate scapulafracture model, and the side, vertical, anteroposterior direction finite elementmechanical comparison of three different loads.(1) stress situations: two platefixation can occur within a certain fixed stress concentration in the lateral stress andvertical stress load conditions, anatomical plates and steel group in the maximumstress fracture performance are better than ordinary reconstruction plate;performance before and after the load conditions and anatomic reconstruction plategroup in steel plate group and the distribution of the maximum stress fracture was nosignificant difference.(2) displacement situation: Three stress load conditions,anatomical plates and steel group in the maximum displacement of the fractureperformance are better than ordinary reconstruction plate.4. Compared two groups of finite element analysis data, anatomicalreconstruction plate steel is relatively common in the more stable complex scapularfracture fixed, firm, to provide a more conducive environment biomechanics offracture healing.Conclusions:The experiment successfully designed scapula anatomical plate and construct athree-dimensional finite element model of a true reaction of the scapula shoulderblade geometry can be simulated biomechanical properties, more traditional method has the advantage of Experimental Mechanics reusable.In this study, three-dimensional finite element analysis of the biomechanicalproperties of the general reconstruction plate and scapula anatomic plate fixation offractures of the scapula in a simulated two different internal fixation of comminutedfracture of the scapula fixed mechanical test model, for anatomical plate scapulafixation system composed of its combat forces in the analysis of the results ofvarious simulated conditions, the fixation stress fracture displacement are superiorto ordinary reconstruction plate. The above experiments illustrate the anatomicalplate fixation system composed of the scapula, and its strong stable, suitable forcomminuted fracture of the scapula, its excellent resistance to compression,bending, torsion performance, to ensure comminuted fracture of the scapula toprovide a good mechanical environment in which the stress fracture site undercontrol, can effectively restore and maintain comminuted fracture of the end of therelationship to the underlying position on the line to promote the healing of thefracture, early weight-bearing activities to ensure that the limb can help speed upthe limb function recovery. Meanwhile, the scapula anatomic plate meets the scapulaglenoid neck, the outer edge, Okabe multiple sites simultaneously fixed and readyfor a variety of complex fractures in patients without preoperative internal fixationdevices, but also the exact location of the fracture broken steel plate cutting make asingle fixed site; during the procedure, to avoid intraoperative adjustment plate, ora minor adjustment can be achieved with the bone surface fit, reduce surgery time,reduce the amount of bleeding, reduce the risk of infection, which greatly reducesintraoperative, postoperative the probability of disease occurrence. Is a practical,strong new auxiliary internal fixation.Therefore, from biomechanical point of view, the scapula anatomic plate canreplace traditional fixed applied within clinical fractures of the scapula bonefixation.