Case 01 - 30 year old female with chronic knee pain while training for a mud run
Case 1: 30 year old female with subacute onset right knee pain while training for a "mud run".
Case discussion:
Note the prominent marrow edema throughout the medial tibial plateau, best seen on the fat-saturated T2 images. Additionally, there is a low signal intensity line extending obliquely through the medial tibial condyle towards the intercondylar eminence, best seen on the coronal T1 images. In the setting of recent overuse, these findings indicate a tibial stress fracture.
The tibia is the most common site for stress fractures. There are two types of stress fractures, insufficiency and fatigue. This case demonstrates a fatigue-type injury, where abnormal stresses are placed on normal bone. Insufficiency fractures occur when normal stresses lead to injury in an abnormal (i.e. osteoporotic) bone.
Also important to note is that there is no significant displacement along the fracture margin.
Expert commentary:
This is a fairly common site of stress fracture, often occurring in undertrained individuals who are ramping up their activities. Clnically, the symptoms and exam may overlap with pes anserinus bursitis and medial meniscal tear.