No abstract

This study aimed to determine whether the volume and mobility of the infrapatellar fat pad (IPFP) change as a result of manual release or stretching during quasi-static knee extension in patients with knee osteoarthritis (KOA). [Participants and Methods] Fourteen patients with KOA were allocated to one of two groups: the manual release (R) and stretching (S, control) groups. They all underwent 12 treatment sessions in in a space of four weeks. We created 3D models of the IPFP, tibia, patella, and patellar tendon using sagittal MRI scans with the knee at 30° or 0°. We compared the differences in (1) the distance of anterior movement of the anterior surface of the IPFP (IPFP movement) and (2) the volume of the IPFP, between the R and S groups, using the 3D models. [Results] Neither group showed any anterior movement of the IPFP during quasi-static knee extension at pre-intervention; however, both groups showed significant anterior movement of the IPFP at post-intervention. IPFP movement decreased in the S group, meanwhile it increased in the R group at post-intervention. [Conclusion] Anterior movement of the IPFP was more increased by manual release than by stretching since the latter may have shortened the distance between the patella and tibial tuberosity at 0° and 30° flexion.

[Purpose] Previous studies suggest that the infrapatellar-fat-pad is affected by aging or knee osteoarthritis, and that the infrapatellar-fat-pad in knee osteoarthritis cases may be associated with limited mobility during knee movement. This study aimed to determine changes in the shape and volume of the infrapatellar-fat-pad between 30° and 0° of knee extension in knee osteoarthritis cases and in young, healthy individuals, and to characterize differences in patellar mobility, patellar tendon mobility, and length between the groups. [Participants and Methods] We created 3D models of the infrapatellar-fat-pad, the patellar tendon, and bones using sagittal MRI with the knee at 30° and 0°. The following four parameters were determined: (1) movement of the infrapatellar-fat-pad; (2) infrapatellar-fat-pad volume; (3) angle and surface length of the patellar tendon; and (4) patellar movement. [Results] Compared with the knee osteoarthritis group, the healthy group showed (1) reduced anterior movement of the infrapatellar-fat-pad; (2) smaller volume changes only in the infero-postero-lateral portion; and (3) no changes in the angle of the patellar tendon to the tibial plateau between 30° to 0°. [Conclusion] In conclusion, between 30° and 0°, (1) the infrapatellar-fat-pad in patients with knee osteoarthritis exhibited less anterior movement, and (2) the patellar tendon angle was diminished in patients with knee osteoarthritis compared with those of young-healthy knees.