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Ilio Tibial Band Syndrome
The ilio tibial band runs from the hip to the lateral side of the proximal end of the tibia. Its function is to resist internal rotation of the tibia as well as to maintain the lateral integrity of the leg. Ilio tibial band “friction syndrome” is a condition wherein the ilio tibial band is stretched and torqued and the distal end rubs across the lateral condyle of the femur.

Symptoms
Patients complain of pain on the lateral side of the knee often extending up the lateral side of thethigh as high as the hip.

Cause
Overstress of the ilio tibial band. During a normal gait cycle, the femur and the tibia rotate together (i.e. internally during pronation and externally during supination); However, when a person over pronates, (foot roles in) the tibia is locked into the ankle joint and therefore continues to rotate internally past the end of the contact phase while the femur begins to externally rotate with the pelvis during midstance phase. The resulting counter rotation of the femur and the tibia causes a shearing force to occur in the ilio tibial band resulting in torquing and stretching. The result is that the distal end of the band rubs across and is irritated by the lateral condyle of the femur.

What can you do
Stop running, especially in the case of severe pain if pain is mild, then reduce training load and intensity and avoid downhill running and running on cambered surfaces.
Apply ice to the knee (for 10minutes every 2 hours) in order to reduce the inflammation 
Remember to stretch well before running
Return to running gradually
Full recovery is usually between three to six weeks

What the Physical Therapist might do
Deep tissue work and stretching of surrounding muscles to help ease the tightness
Mobilise foot, ankle, knee and hip
Ice to reduce inflammation
Since the problem is the abnormal pronation, the patient should be fitted with
Prescription Orthotics to correct the prolonged pronation thereby reducing the counter rotation between the femur and the tibia, alleviating stress off of the ilio tibial band.