Imaging Analysis Of The Correlation Between Tibial Tuberosity-trochlear Groove Distance And Femoral Trochlear Morphology

Objective:To investigate the possible relation between tibial tuberosity-trochlear groove(TT-TG)distance and trochlea morphology.Method:A total of 154 CT scans from June 2019 to August 2019 were analyzed retrospectively,.There were 80 males and 74 females,aged 18~55 years.Based on Dejour trochlea classification,the subjects were divided into two groups: trochlea dysplasia group(type A-D)and normal group(sulcus angle≤145°).Researchers measured TT-TG distance and radiologic parameters characterizing the form of trochlea on PACS,including sulcus angle,the lateral trochlea slope,trochlea height(medial,central,lateral),trochlea depth,trochlea facet asymmetry.The Man-whitney U test was used to evaluate differences in TT-TG distance between trochlea group and normal group.Pearson correlation ananlysis was performed between TT-TG distance and parameters of trochlea morphology.P value<0.05 was set as a significant difference.Results:Trochlea dysplasia group showed higher values for TT-TG distance than normal group.TT-TG distance significantly correlated with most trochlea parameters evaluated,including sulcus angle(r=0.487 P<0.001),the lateral trochlea slope(r=-0.286 P<0.001),medial trochlea height(r=-0.174 P=0.031),trochlea depth(r=-0.299 P<0.001),trochlea facet asymmetry(r=-0.301 P<0.001),Dejour trochlea type(r=0.496 P<0.001).No correlation was found in lateral trochlea height(r=0.001 P=0.993)and central trochlea height(r=0.102 P=0.210).Conclusion:Our study showed TT-TG distance is significantly related to the femoral trochlear dysplasia.This result supports the hypothesis that the stimulation of the patellofemoral compression can affect the development of trochlea,and provides a theoretical basis for the clinical treatment of children with patellofemoral instability.