RESUMO
Objective To investigate relative translations of the glenohumeral joint during abduction, scaption and forward flexion in normal Chinese, so as to provide references for diagnosis, treatment and follow-up of glenohumeral joint instability and subacromial impingement syndrome.Methods The biplanar fluoroscopy system combined with model-image registration technique were used to measure the humeral translation relative to the scapular in 13 healthy volunteers during abduction, scaption and forward flexion.Results The anterior-inferior glenohumeral translation during abduction, scaption and forward flexion was (4.0±1.3), (4.1±1.5),(4.8±1.9) mm, respectively. The superior-inferior glenohumeral translation was (3.0±1.0), (3.1±1.1), (3.3±1.5) mm, respectively. During the whole motion, there was a significant difference in superior-inferior translation at different arm elevation angles, while other significant differences were not found.Conclusions For normal Chinese, the humeral head was positioned posteriorly and superiorly on the glenoid. During forward flexion, the anterior-inferior and superior-inferior glenohumeral translation was the maxium. Therefore, in the process of clinical diagnosis, treatment and follow-up, patients performing the forward flexion may obtain a better evaluation effect.
RESUMO
Objective To explore the influence of hook deflection angle and inclination angle on mechanical properties of the soft tissue suture passer hook. Methods Taking the end face far away from the tip of the needle (end face 1) as the study object, a mathematical model was established with the moment as dependent variable and the hook deflection angle and inclination angle as the independent variable. The moment was solved by the mathematical model with the deflection angle and inclination angle of 0°, 10°, 20° and 30°. Based on the finite element analysis method, 16 three-dimensional geometric hook models with deflection angle and inclination angle of 0°, 10°, 20° and 30° were established by SolidWorks. The stress analysis was carried out by ANSYS Workbench. Under the same puncture force, the maximum von Mises stress of each hook and the reaction moment of end face far away from the tip of the needle were calculated. Results The results from theoretical analysis and numerical simulation showed that the reaction moment of end face 1 increased with the increase of deflection angle, and increased with the decrease of inclination angle. The hook with deflection angle of 0° and inclination angle of 30° had the minimum reaction moment. The finite element analysis results showed that with the deflection angle of 0°, the maximum von Mises stress of the hook was the smallest and did not change with the inclination angle of the hook changing. Conclusions The established mathematical model can accurately explain the relationship between the moment at the end face of the hook and the deflection angle and inclination angle of the hook. This study provides the theoretical basis for designing hook geometry of the soft tissue suture passer, and improves the safety of the soft tissue suture passer in operation process.
