Patella-patellar tendon angle decreases in patients with infrapatellar fat pad syndrome and medial patellar plica syndrome

Abstract

Purpose Infrapatellar fat pad (IPFP) syndrome and medial patellar plica (MPP) syndrome are two recognized causes of anterior knee pain. However, diagnosing these syndromes is challenging without arthroscopic examination. The aim of this study was to evaluate sagittal patellar tilt in patients with IPFP syndrome or MPP syndrome by measuring the patella-patellar tendon angle (PPTA) in affected patients. Methods Eighty-three patients with anterior knee pain who underwent diagnostic arthroscopy that confirmed isolated IPFP or MPP syndrome from 2011 to 2016 were included in this retrospective study. Patients were divided into Group A (IPFP syndrome, n = 44) and Group B (MPP syndrome, n = 39). The control group included 78 patients without knee pathology who underwent magnetic resonance imaging (MRI) of the knee during the study period. Radiographic measurements, including PPTA, IPFP area, patellar height, axial patellar alignment, patellar tilt, sulcus angle, and lateral trochlear inclination, were made on MRI images by two experienced sports medicine orthopedists. ResultsThe mean PPTA in each knee-pathology group was significantly smaller than that in the control group (Group A: 137.3° ± 4.9°; Group B: 138.1° ± 3.2°; control group, 141.4° ± 2.9°). There was no significant difference between groups for any other radiographic parameter evaluated. ConclusionThe PPTA was significantly smaller in patients with IPFP syndrome or MPP syndrome than in healthy controls. Therefore, sagittal patellar tilt should be included in the routine evaluation of patients with anterior knee pain. Evaluation of PPTA may help to diagnose IPFP syndrome or MPP syndrome. Level of evidence Level IV.

Patella-patellar tendon angle in relation to the medial patellar plica syndrome, chondromalacia patella, and infrapatellar fat pad syndrome

“…In the present study, sagittal patellar tilt was evaluated in patients with MPP syndrome, chondromalacia patella, and IPFP syndrome by measuring PPTA. This study demonstrated that PPTA was significantly lower in patients with MPP syndrome, chondromalacia patella, and IPFP syndrome than in those of control group, which was consistent with the results of previous studies [ 3 , 4 ]. However, there was no significant difference in PPTA among the patients in each disease.…”

“…The most known reasons of AKP are trauma and overuse [ 12 , 13 ], but MPP syndrome, chondromalacia patella, and IPFP syndrome are well-known conditions that could cause AKP [ 3 , 4 ]. The medial, lateral, superior and inferior synovial plicae are normal structures of the knee joint, but plica-related AKP is mostly caused by impingement of medial plica.…”

“…Anterior knee pain (AKP) is a common clinical symptom, accounting for 11–17% of physician visits for knee symptoms, but the diagnosis of AKP is often challenging [ 1 , 2 ]. Although the causes of AKP vary, medial patellar plica (MPP) syndrome, chondromalacia patella, and infrapatellar fat pad (IPFP) syndrome are well-known causes of chronic AKP [ 3 , 4 ]. MPP syndrome and IPFP syndrome could be diagnosed based on clinical symptom, physical examination, and MRI, but the accurate diagnosis could also require arthroscopic findings [ 5 – 8 ].…”

“…Sagittal patellar tilt is assessed by measuring the patella-patellar tendon angle (PPTA) [ 3 ]. Some previous studies reported that patients with MPP syndrome, chondromalacia patella, and IPFP syndrome had smaller PPTA than healthy individuals [ 3 , 4 ]. However, there is limited published information whether there is a difference in PPTA according to each different patellofemoral joint disorder.…”

Volume and mobility of the infrapatellar fat pad during quasi-static knee extension after manual therapy in patients with knee osteoarthritis: a randomized control trial study

“…Therefore, the IPFP in KOA patients was more like that of young, healthy people after manual release. Kim et al 23) reported that the patella-patellar tendon angle was smaller in patients with IPFP syndrome (137.3 ± 4.9° (± SD)) than in people without knee pathology (141.4 ± 2.9°) (p<0.001). Assuming that the control group has better knee function, we speculate that improving mobility of the IPFP in patients with KOA may help to achieve better knee function.…”