Patellofemoral anatomical measurements on MRI in patient with suprapatellar fat pad edema and mass effect

Abstract

Objective: To evaluate the impact of patellofemoral joint anatomical measurements of patients with anterior knee pain who were diagnosed with suprapatellar fat pad (SPFP) impingement syndrome (SP-FPIS) by magnetic resonance imaging (MRI). Study Design: A prospective, descriptive study. Place and Duration of Study: Goztepe Education and Research Hospital, between March 2015 and June 2019. Methodology: The study included 34 patients (Group 1) and 34 healthy volunteers (Group 2) who were referred to the radiology clinic with anterior knee pain; they underwent MRI and diagnosed with SP-FPIS. Twenty-three anatomical measurements such as SPFP cranio caudal length (CC), anteroposterior length (AP), oblique length (OBL), patellar length (PL), patellar tendon length (PTL), Insall Salvati Index (ISI), patellar cartilage distal-tibial tubercle (TT), patellar cartilage length (PCL), Modified Insall Salvati Index (MISI), patellotrochlear cartilage length (TCL), lateral trochlear inclination angle (LTI), etc. related to the morphological structure of SPFP and patellofemoral joint were evaluated and compared in both groups. Results: The mean age of groups 1 and 2 was 45.62 +/- 10.87 and 41.47 +/- 11.98 years, respectively. There was a statistically significant difference in patients with SP-FPIS in PL, PT, TT, PC, MISI, TC, PTI, MF, PHY, PPI, MT, LTI, CC, AP, and OBL measurements compared with the control group (p<0.05). In the logistic regression analysis performed to evaluate the effect of statistically significant parameters on anterior knee pain, the probability of SP-FPIS increases 1.5 times as PTL increases among the groups, while the risk of SP-FPIS decreases 0.78 times as LTI decreases (p<0.05). Conclusion: There is a predisposing effect of PTL increase in SP-FPIS development, while LTI decrease has a protective effect. These results will guide future studies for the development and/or modification of treatment methods.