Work

Lateral patellar maltracking and patellar alta in the absence of increased TT-TGdynamic distance in isolated patellofemoral pain: a dynamic kinematic CT study

Year: 2025

Type: article

Abstract: Background Patellar tracking in isolated patellofemoral pain needs further confirmation under dynamic conditions. The present study aimed to analyze the characteristics of patellar tracking and tibial tubercle-trochlear groove (TT-TG dynamic ) distance during active knee motion in patients with isolated patellofemoral pain (PFP) via dynamic kinematic computed tomography (DKCT), and clarify whether the abnormal patellar tracking and TT-TG dynamic distance are associated with isolated PFP. Methods A total of 47 knees with isolated PFP and 47 control knees were scanned with DKCT. The TT-TG dynamic distance, bisect offset (BO) index, lateral patellar tilt (LPT), and patellotrochlear index (PTI) were evaluated. All parameters were analyzed by two-factor repeated measures ANOVA. Results In the two groups, the TT-TG dynamic distance, BO index, LPT, and PTI varied with the knee flexion angle (all p <0.001). Between the two groups, the variation trends of TT-TG dynamic distance and BO index were consistent ( p = 0.131, 0.284, respectively), while those of LPT and PTI were significantly different ( p = 0.001, <0.001, respectively). The BO index and LPT were significantly higher in the PFP group than those in the control group ( p = 0.002, <0.001, respectively), and the PTI was significantly lower in the PFP group than that in the control group ( p <0.001), whereas the TT-TG dynamic distance showed no significant difference between the two groups ( p = 0.631). Conclusions Abnormal lateral patellar displacement, tilt and patellar alta occurred in the absence of increased TT-TG dynamic distance in isolated PFP without trochlear dysplasia. Etiologic analysis of isolated PFP should emphasize lateral patellar tracking and patellar height.

Source: BMC Medical Imaging

DOI: 10.1186/s12880-025-01999-1