Sunday 8 July 2012

ITB Pain

One of the most common running injuries in an overuse sense is the dreaded ITB Pain we experience on the lateral portion of the the knee. It's a well documented injury, but often poorly treated and can become chronic.

So what happens.....

The ITB attaches from the iliac crest with fibres converging from the TFL and Glutues maximus forming a dense band that thickens distally and attaches onto Gerdy's tubercle on the fibula and a number of fascial slips attaching to the lateral patella (kneecap).  During it's course inferiorly to it's attachment, it runs over the femoral condyle. This thick band is composed mainly of Type 1 Collagen and Type 3 Collagen in the distal portion (last 5-6cm). This thick  protein is very dense, non contractile and stretches about 4-6% of it's resting length. To reduce friction as it crosses over the femoral condyle a bursa underlies the tissue and over the boney prominence, thus acting to reduce friction at this site during repetitive flexion/extension of the knee

During the gait cycle the ITB acts as a stabiliser to the ipsilateral (same side) hip complex creating stability through the hip/knee/foot as it contacts the ground particularly through the mid stance phase.  The Gluteus minimus and medius (side glutes), TFL and lower down the Tibialis anterior and Tibialis posterior resist the ground reaction forces imposed and act to control the amount of internal rotation through the femur, tibia and subsequently at the foot slowing down pronation.

Failure of these muscles to provide the amount of stability required results in an increased amount of internal rotation through the tibia and femur. As the the knee goes through approx 20-30 degrees flexion with increase internal rotation the distal ITB is pulled slightly posteriorly over the prominence causing an increase in friction over the femoral condyle. This is often worse on long slow runs as fatigue sets in and during downhill running. Quicker interval type training ie; 200m reps often cause minimal pain. This is due to two main reasons;

1. Faster running spends less time in the 20-30 degree knee flexion range where 'friction' is at it;s greatest
2. Faster running tends to increase activation of your hip stabiliser muscles (Gluteus minimus and medius) decreasing internal rotation at the hip and knee and lowering your centre of gravity

Once the bursa becomes inflamed there is now an increase in friction in an already compromised site.
Remember the importance of the Gluteus minimus and medius as stabiliser of the hip and knee? With these failing to work the consequence is a traction at the lateral knee. So while the pain is at the  knee the cause is most certainly at the hip!!

A common theme with ITB is often heard " my ITB is tight"! Well, your ITB is meant to be tight by it's very attachment and function. Remember the ITB stretches only 4-6% of it's original length and it is not contractile - so it's very anatomic make up doesn't lend itself well to stretching all day and rolling on a roller to lengthen the ITB. Look to the cause!

So how do we treat it and how long off running?

Depending on how long it is has been going on will partly depend on how long you may need off. Most episodes will resolve within 4-6 weeks however in this time it important to address those musculoskeletal imbalances. Most of the time the gluteal stabilisers will need to increase their activation through the gait cycle on the same side. There will be further soft tissue consequences such as an increase in loading through the anterior hips structures to assume the load of the structures not firing properly (either not at all or late!). You will often find Psoas, Iliacus, TFL to be overactive. There may be ramifications further down the chain particularly with Tibialis posterior a lower limb stabiliser that needs to be able to resist pronation forces.

Treatment will involve soft tissue treatment to overactive structures, unloading of the knee (no running), activation exercises initially from isolation to integration for the hip stabilisers and getting range of motion back if you have decreased ranges in the hip/knee/foot areas. One key point for exercise based treatment in the standing/dynamic positions is getting your pelvis into neutral and even slightly anteriorly works well. If you can integrate that position into your running gradually you will notice better hip and knee control and usually a more efficient stride

You don't need to roll on a your ITB all day unless you enjoy it! This will have minimal effect on the outcome unless you deem that your Vastus lateralis (side portion of quads) is in need of some deep tissue work. Once you have recovered and can self manage a graduated (us runners are poor at this!!) running program should commence keeping cambered and down hill runs off  limits initially.

What about Cortisone?

Cortisone definitely has it's place in sports medicine and can be a adjunct to the treatment as long as the underlying cause is being dealt with. It is rarely effective in ITB as a stand alone treatment. Anti-inflammatories may provide a small amount of help, however in my experience inflamed bursal tissue can be extremely hard to work with. Taking the load off is the first option

Biomechanics

I am certainly not a bio-mechanist however i have worked with one on my own running for 2 years. Most runners do not run with good form. Running is a skill just as any other sport, however it amazes me that running is the most overlooked sport (middle-long distance) when it come to biomechanics. Most other sports # 1 factor is technique - not running! This needs to change when you look at the injury rates for running. If you are constantly getting injuries bouncing all over the place - this would be a place to start.

There is a lot more that can be written on this subject and this is certainly not exhaustive! I hope this article has shed some light on the possible cause of ITB pain and treatment options.

Jimmy Barker

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