RESUMEN
Objective To evaluate the application of imaging analysis system based on three-dimension computed tomography (3D-CT)for the diagnosis of femoral trochlear dysplasia.Methods Between May 2013 and January 2014,30 patients were diagnosed as recurrent patella dislocation and received surgical treatment.All the patients received 3D-CT diagnosis of the knee joints preoperatively,and the data of 3D-CT were transferred to imaging analysis system with MIMICS software that would be used to get the trochlear dysplasia index.The patients were also received knee fluoroscopic detection.A true lateral view was also used for evaluation of the trochlear dysplasia as the classic method.The difference between the two methods was compared.And the sensitivity,specificity,positive and negative predictive value of the imaging analysis system were analyzed.Results The mean trochlear dysplasia index was 5.3 ± 1.8 mm (3.2 to 8.4 mm)using the classic fluoroscopic method,showing no significant difference from the result according to the imaging analysis system,5.2 ± 1.5 mm (3.5 to 8.1 mm).When the fluoroscopic method was set as the golden standard,the sensitivity,specificity,positive and negative predictive value of the imaging analysis system were 89.5％,81.8％,89.4％ and 82.0％ respectively.Conclusion The imaging analysis system based on 3D-CT of knee joints could provide acceptable results without good sensitivity and specificity,without significant differences from the classic fluoroscopic method.So it is a more safer and easier approach worthy of clinical implication.