(Credits: This post is inspired by a recent Journal Club discussion)
image credit from: http://saveyourself.ca/tutorials/iliotibial-band-syndrome.php
The Ilitotibial Band (ITB) pain that many people seek relief from and many of us will treat is a confusing phenomena. The ITB lies lateral to the thigh as a thickening in the compartmental fascia of the upper leg. Proximally the tensor fascia lata and gluteus medius insert into the band and distally the fascia inserts onto the lateral femoral condyle and the proximal lateral tibia at Gerdy’s tubercle. The ITB also dives perpendicular to the fascial plane to meet and attach to the femur along the lateral linea aspera. The muscle belly diectly under the ITB is primarily the vastus lateralis muscle and the cutaneous sensory innervation along the ITB is the lateral femoral cutaneous nerve.
More on the anatomy and findings? Here is a link to a wonderful MRI study of ITB friction syndrome from 1999: Iliotibial Band friction Syndrome-MRI Findings in 16 Patients and MRA Study of Six Cadaveric Knees . The findings? There were signal intensity findings in the posterior lateral compartment created by the ITB, lateral joint capsule, fibers of the popliteus insertion and fibers of the lateral meniscus and vastus lateralis just external to the joint capsule.
The main belief is that the ITB rubs on distal structures with repetitive motion. Basically a simple biomechanical-irritant-causing-the-firing-of-nociceptors type of diagnosis. Seems simple.
A quick literature review will find multiple explanations with multiple treatment programs. Let’s review some of the commonly held beliefs about the causes:
1. The ITB rubs over the femoral condyle and later proximal tibia and causes pain to the individual. However, it has equally been hypothesized that since the ITB is simply a thickening of the fascia it cannot slide over anything in an abnormal fashion, since fascia’s job is to encase and slide. Patients often report a snapping over of the band, but this is inconsistent. Studies have shown that the posterior fibers of the ITB at the knee do compress structures at certain degrees, see # 6 below.
2. Poor mechanics and weakness at the hips can cause ITB pain. Ok, sure, but hip movement would only affect the proximal band since the distal band is sheltered from superior stress by the insertion of the ITB into the femur between the two areas. It seems unlikely that hip stresses to the fascia show up as pain in the knee.
Hip weakness is also unlikely since the patient population that ITB pain is found in is athletes. Any weakness found on exam is probably more due to pain induced inhibition or changes in motor control as a protective mechanism.
3. Knee valgus position can cause unnatural tension and pulling on the ITB. Knee valgus may cause compression of the lateral compartment, but it is more likely that genu varus causes the ITB to be tensioned over the joint to increase the pressure on underlying structures. However, medial-lateral knee position should be generally static through life, so what are you going to fix about a person with congenital knee varus?
4. There are inflamed bursa or cycts in that area that are the source of pain. Yes, a supracondylar bursa has been implicated. Bursa can develop as a protective result from mechanical stresses. And studies showed no bursa inflammation (or even bursa existence) in some individuals, same goes with the cysts.
5. The ITB is too tight and is compressing the structures and causing nociception. Yes, a tight ITB has been found in many with ITB pain… and, of course, (thank you science) a loose ITB has been implicated as well.
6. Knee flexion/extension angle upon impact may cause a shift of normal biomechanics and cause ITB symptoms. Yes, this was deonstrated and hypothesized that at about 20-30 degrees the pain would come on. Then a study showed there is no relation to knee angle and the above MRI article shows no conclusive contact at any specific angle.
Also, since this is considered an overuse injury, the camber of the road a runner is on or running the same route can cause unilateral stresses on the ITB. Then again, cyclists get frequent ITB complaints and they are constrained by the ergonomics of their bike, are they not?
7. ITB pain comes from over pronation at the ankle. Yes, a study supports this, and a study also found the opposite.
8. A compartment like syndrome may be occurring. It is hypothesized that since the vastus lateralis is in use it is being constrained within the fascia and this is the somatic pain of ITB friction syndrome. This sounds very biologically plausable, and has some evidence to support it, however this seems to be a newer thought and not yet put through the ringer of science. (Notice how big a VMO gets when unconstrained by tight fascia, could the vastus lateralis be yearning for that much free space as well?)
So the causes seem to be all 50/50 for and against. What we seem to take from all this ( and there is more I’m sure ) is that there may in fact be multiple lateral knee pathologies with a similar Mechanism of Injury (overuse) that we singularly call ITB pain or syndrome.
The treatment approaches are seemingly no more clear. (This must be due to the fact that the pathology is so variable for this named syndrome)
What seems to work the best is a combination of standard and specific physical therapy treatments, often including foam rolling, aimed at the individual’s presenting symptoms. If the glutes are weak, strengthen them. If they have poor mechanics, try to neutralize them, etc. If the ITB is tight, you can stretch it. This last one always stirs a debate about how much time and force it takes to reform and elongate collagen. Most now come down on the side of -1. actual tissue lengthening takes longer than people are willing to stretch, to get into the ‘creep’ phase. 2. it takes more force to stretch the ITB than we can generate in a stretch.( I personally agree with point one and have not quite decided about point 2. In my estimation most length gains are seen from neural adjustments to tissue stress signals.)
In treatment the common thread that is implicated in this syndrome is rest from the irritating activity. As a therapists it will be hard to get any athlete to rest from their adrenaline producing dopamine releasing activity, but this seems to the one thing that really works. As noted in the research, therapists are often happy with their own personal techniques and outcomes that they see from their experience. This seems to be a syndrome/condition where clinician experience should be favored since at this time the evidence is not decisive.
One thing that we CAN accurately say is this: The patient is experiencing lateral knee pain when performing a repetitive activity. Right now, this is the most true while being the least false. I look forward to evaluating and treating this complex syndrome and to seeing what research continues to come out on lateral knee overuse pain.
– Matt D
Lavine R. Iliotibial band friction syndrome. Curr Rev Musculoskelet Med. (2010) 3:18–22
Beals C, Flanigan D. A review of treatments for iliotibial band syndrome in the athletic population. Journal of Sports Medicine. (2013). Accessed 4/11/14. http://dx.doi.org/10.1155/2013/367169