Knee | Tendinitis | Postero medial friction syndrome
50 year old patient presenting with postero medial knee pain elective knee pain : US exploration is negative, complementary MRI is undergone :
Image (a) : Axial DP FAT SAT weighted slice of the right knee passing through femoral condyles : liquid collection in keeping with a bursitis (purple arrow) situated between the sartorius tendon (blue arrow) and the posterior aspect of the medial femoral condyle. Orange arrow : gracilis tendon, Red arrow : semimembranosus tendon, green arrow : semitendinosus tendon.
Image (b) : Corresponding coronal DP FAT SAT weighted slice : bursitis (purple arrow) situated between the sartorius tendon (blue arrow) and the posterior femoral condyle.
This case illustrates a postero medial friction syndrome, between the sartorius tendon and the posterior aspect of the medial femoral condyle, explaining the patient's symptoms.
The hypothesis of the key factor is the proximity between the anserine tendons (notably sartorius and gracilis), and the posterior medial aspect of the femoral condyle.
A retrospective study carried in 2015 including 27 asymptomatic subjects and 27 patients presenting with postero medial friction syndrome confirmed by MRI showed that there was a statistically significant difference in the distance between the sartorius/gracilis tendons and the femoral condyle, which was reduced for symptomatic patients compared to asymptomatic ones.
Posteromedial knee friction syndrome: an entity with medial knee pain and edema between the femoral condyle, sartorius and gracilis.
