Mohammad Amin Mahdiyar; Mohammad Taghi Karimi; Hamid Namazi; Hussein Malekjamshidi
Volume 11, Issue 4 , October 2023, , Pages 173-177
Abstract
Objective: This study aimed to compare the outcomes of fixing scapholunate with pins and screws in parallel,convergent, and divergent orientations.Methods: In this computer simulation study, the CT scan images of a healthy subject wereused to construct a 3D model of the wrist joint using MIMICS software. ...
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Objective: This study aimed to compare the outcomes of fixing scapholunate with pins and screws in parallel,convergent, and divergent orientations.Methods: In this computer simulation study, the CT scan images of a healthy subject wereused to construct a 3D model of the wrist joint using MIMICS software. The imposed force to scaphoid and3D model lunate bones, as well as the scapholunate angle and distance, were compared in different surgicaltechniques using parallel, divergent, and convergent pins and screws.Results: In the absence of external force, the imposed stress applied to the scaphoid and lunate bones in casesof parallel pins and screws were 7.5MPa, 5.08MPa (pins), 1.134MPa, and 1.151MPa (screws), and 10.90MPa,10.90MPa (pins), 9.7MPa, and 34.1MPa (screws) for 50N flexion force. The imposed stress in this approach issignificantly lower compared to other interventions. Better outcomes were seen regarding scapholunate angleand scapholunate distance in using parallel pins or screws as well.Conclusion: In conclusion, implementing parallel pins and screws for scapholunate fixation had better resultsin terms of achieving carpal stability in scapholunate dissociation. However, fixation with pins and screwsshowed a statistically significant difference. Furthermore, a wide range of motion exercises with no additionalforces can be used in the rehabilitation of patients undergoing this surgery.
Ali Ghaemmaghami; Ehsan Fallah; Hamid Namazi; Mohammad Taghi Karimi; Seyed Iman Houseini
Volume 9, Issue 1 , January 2021, , Pages 9-14
Abstract
Objective: To compare the stability of the radius stabilized fractured parts by volar and dorsal planting based on modeling approach. Methods: Ten forearm models were created based on Computed Tomography (CT) Scan images by using of Mimics software. The distal part fracture of radius was induced in the ...
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Objective: To compare the stability of the radius stabilized fractured parts by volar and dorsal planting based on modeling approach. Methods: Ten forearm models were created based on Computed Tomography (CT) Scan images by using of Mimics software. The distal part fracture of radius was induced in the models. The stress were developed and implanted in various parts of the bone and and their displacement were evaluated in volar and dorsal inserted implants. Results: The results of this study showed that the stress developed in screws, implant and bony parts differed significantly between volar and dorsal plate conditions. The displacement of implant and bony parts in volar plating was more than dorsal plating (p=0.05). However, the screws displacement in dorsal plating significantly increased compared to volar plating. Conclusion: The stress developed in dorsal and volar implants is not too high to fail the structure. However, it seems that the irritation of soft tissue and tendon would be less in volar inserted implant than dorsal implant. It is recommended to use valor plating to be a good approach for stabilizing the distal part fracture of radius.