Sunday, November 29, 2020

Arch Supports And Iliotibial Band (ITB) Pain


A patient came in this week after being diagnosed with Iliotibial band (ITB) syndrome. The outer part of his right knee would hurt badly after running about 1.5 km. After stopping to walk, he would be able to run for a few minutes before having to stop again. 

He had been running 4-5x each week, clocking about 50 km weekly. He had just seen a sports doctor who first referred him to a podiatrist to get orthotics as he 'pronated' badly.

After getting his orthotics, he 'pronated' less according to the prodiatrist who filmed him while running on a treadmill. But, alas, his ITB/ knee pain didn't change. Since I'd treated a fellow runner he knew, he came to see me, hoping I could help him run pain free.

The ITB starts from the TFL
I've written previously about the ITB and you can read more about it here (anatomy) and here. If you look at the picture above, you can see it starts from Tensor Fascia Lata (TFL) muscle and runs down the outer thigh before finishing just at the outer part of the knee (picture below). This is usually where runners experience a sharp pain.

Also know as iliotibial tract (bottom R of pic)

Studies show that when the hip rotates medially or drop inwards, a strain is placed on the ITB . This also causes the tibia (or shin bone) to rotate inwards causing the foot to pronate (or ankle eversion). 

Researchers have attempted to correct this by changing ankle pronation to see if this might relieve the strain on the ITB.

In this published paper, 30 runners (15 males, 15 females) with no ITB insertion pain were prescribed orthotic wedges to put into their own running shoes. The wedges were 7 degrees lateral, 3 degrees lateral, no wedges, 7 degrees medial and 3 degrees medial. A total of five running trials were done.

The runners were analyzed by video motion analysis while running at their self selected running pace to calculate motion forces and ITB strain.

The orthotic wedges significantly changed ankle eversion (or pronation) angles compared to no wedges. However, the strain rates did not differ between conditions. There was no change in knee joint angles and tibial rotation under all orthotic wedge conditions. 

The researchers concluded that orthotic wedges may not change forces acting on the ITB, even though they altered foot pronation while female runners had greater strain forces acting on their ITB's potentially due to increased internal hip rotation.

It is interesting to note that the female runners demonstrated significantly greater peak ITB strain and strain rates compared to the male runners, potentially due to increased hip internal rotation (because of wider hips and pelvises for child bearing purposes). I have written at length before that for female runners, their knee pain is coming from their hips. Always treat the cause of the problem. Do not treat the pain alone.

Take home message is that even though orthotic wedges can correct your foot's pronation, it may not alter forces acting on your ITB. This means that your knee pain may not get better using orthotic wedges.

Of course any one reading this may say that these off the shelf orthotic wedges are not customized and that the subjects were all wearing different running shoes. Personally I feel that the different shoes are not an issue as these orthotic wedges used in the study did significantly change ankle pronation so they did what they were supposed to do. 

Would this then be fair to say that using orthotics to change ankle pronation or eversion angles does not seem to benefit those with ITB pain at the knee? Perhaps any podiatrists reading this would like to comment.


Reference

Day EM and Gillette JC (2019). Acute Effects Of Wedge Orthoses And Sex On Illotibial Band Strain During Overground Running In Nonfatiguing Conditions. JOSPT. 49(10): 743-750/ DOI: 10.2519/jospt.2019.8837

2 comments:

  1. Hi Gino, I saw your post about the Accessory Navicular Bone patient. I have this issue and would like your help. Do you have an email address? Thanks

    ReplyDelete