Dynamic Change in Ultrasonographic Findings in Iliotibial Band Syndrome After Running
Ultrasonographic examination (LogicE; GE Inc, 12-MHz transducer) of both knees was performed before and immediately after running to evaluate for structural or vascular changes around the ITB. He was instructed to run on the treadmill at his self-selected speed until his knee pain was reproduced to the severity forcing him to stop running. Ultrasonographic parameters assessed included the thickness of the ITB over the lateral femoral condyle and the vascularity of the ITB and surrounding tissues.
After running for 15 mins, he had to stop running because of lateral knee pain. Ultrasound evaluation (Fig. 1) of the symptomatic knee revealed an increase in thickness of the ITB at the lateral femoral condyle after running compared with the baseline (1.9–2.5 mm). In addition, increased vascularity was noted in the adipose tissue underlying the ITB but not in the ITB itself on the symptomatic side after running. There was no change in thickness of the ITB or vascularity on the asymptomatic side.
The ITB is a thick band of fascia extending from the distal portion of the tensor fascia lata over the lateral femoral condyle, which then fans out to insert at Gerdy tubercle and multiple other attachments in the lateral knee. The etiology of ITB syndrome is commonly thought to be related to a “friction syndrome” of the ITB rolling over the lateral femoral condyle; however, cadaver studies have shown firm anchoring of the ITB, which would prevent rolling.1,2 An alternative hypothesis exists in the literature that fat pad compression deep to the ITB rather than the ITB itself may be the structure prone to inflammation.3 The ultrasonographic findings in this case may support this hypothesis.
Iliotibial band syndrome is a very common condition in runners, which presents as a gradual onset of pain on the lateral side of the knee with running.4 Transient symptoms only related to running often make it difficult for clinicians to examine patients when they are symptomatic. This case also demonstrates the utility of point-of-care ultrasound in evaluating musculoskeletal conditions, which are provoked by certain activities.