In the literature superolateral part of Hoffa fat pad (SHFP) impingement has been described associated with three of patellar maltracking parameters: patella alta, increased tibial tubercle-tibial groove(TT-TG) and decreased distance between the posterior part of the patellar tendon and lateral trochlear facet. However, the relationshipbetween trochlear dysplasia, patellar morphology (Wiberg classification) and patellofemoral inclination angle have not been demonstrated statistically significant. These patients present knee pain that is exacerbatedwith hyperextension but its importance is controversial because there areasymptomatic people with edema in the SHFP. In...

Knee MR studies between 2006 and 2018 were retrospectivelyreviewed. Patients were included if they had undergonetwo different knee MR studies, the first made in 2006 or 2007 and the second with alatency period of at least 3 years. We found 196 patients who had two knee MRI, both left or right knees. MRI were performed using three different 1.5-T systems (Phillips Ingenia, Phillips Achieva and Phillips Intera) with a dedicated knee coil.Patients were placed in the supine position with the knee extended at the maximum...

The mean age was 32.7± 15.68 (range: 13-66 years old)in control group and 38.62 ± 12.77 (range:12-62 years old) in SHFP impingment group. 9 patients were male and 9 were female in control group and19 patients were male and 16 were female in SHFP impingement group (Figure 12). A statistically significant difference (p= 0.038) was found between theTT-TGdistanceof the SHFP impingement group measured in the initial study and the posterior MRI study, but no differences were observed between the TT-PCLdistance between the initial studies and...

⇒An association between a high-patella and an increased TT-TG and SHFP impingement exist, suggesting that SHFP impingement may be an indicator of patellofemoral maltrackig. ⇒ The variability of TT-PCL in different MR studies of the same patient is lower than that of TT-TG, and could be a very useful parameter in the MRI study to confirm patellofemoral instability. TT-TG evaluates the position of the tibial tubercle relative to the femoral trochlea, but it is difficult to calculate in dysplastic trochlea and it varies if the...

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