ITB Friction Syndrome

Introduction

The iliotibial band (ITB) is a sheet of fibrous tissue that sits on the outer side of the thigh. It arises above the level of the hip joint and passes down across the other side of the hip, where a muscle called the tensor fascia lata attaches to its back portion. It then passes down the outer side of the thigh and then crosses the outer side of the knee joint to attach onto a lump of bone on the front/outer (anterolateral) aspect of the top of the tibia (shin bone), called Gerdy’s Tubercle. At each side of the knee there are collateral ligaments that stop the knee wobbling inwards or outwards. These ligaments arise from small bony protruberances on the inner (medial) and outer (lateral) sides of the end of the femur (thigh bone), and are called the medial and lateral epicondyles. The medial epicondyle is well covered with the thick mass of the vastus medialis part of the inner quads muscle. The lateral epicondyle, however, is fairly exposed, without much soft tissue covering, and the ITB passes directly over this. When the knee is extended (straight) the ITB lies mainly in front of (anterior to) the lateral epicondye. When the knee is flexed (bent) the ITB sits mainly behind (posterior to) the lateral epicondyle.

View of a knee from the outer (lateral) side. The grey dot represents the location of the eminence of the lateral epicondyle. As the knee flexes and extends, the ITB passes in behind then in front of the lateral epicondyle.

If a patient has a tight ITB and a prominent lateral epicondyle, and if they do a lot of exercise that involved repetitive flexion and extension of the knee – in particular, running, but also sometimes with cycling – then the back of the ITB can rub repetitively on the lateral epicondyle and this can cause inflammation, which causes pain in this specific area (on the lateral side of the knee). If a patient has a painful inflamed ITB then this is called ITB Friction Syndrome. ITB Friction Syndrome tends to give fairly classic symptoms. Patients tend to be fine when they start running (or cycling), but then with time (and this tends to be after a specific distance or time, which decreases as the condition gets worse) the patient develops a burning pain on the outer side of the knee with specific point tenderness in the region of the lateral epicondyle and distal ITB. If they continue to run then the pain gets worse. With rest the pain will gradually ease off. Also, classically, if patients avoid running/cycling and instead do exercise such as the cross-trainer or swimming with front crawl legs only (where there is very little knee flexion and extension) then they tend not to develop their lateral knee symptoms.

Investigation

The diagnosis of ITB Friction Syndrome is normally fairly obvious just from the patient’s history and their symptoms. The clinical examination is also fairly classic, and there is a specific test for ITB Friction Syndrome called ‘Ober’s Test’, which is where actively resisted abduction of the leg combined with repeated flexion and extension of the knee causes pain and specific tenderness directly over the lateral epicondyle. In order to exclude any other pathology in the knee, your surgeon may well refer you for an MRI scan, particularly to exclude the possibility of any meniscal or articular cartilage damage in the lateral side of the knee. However, the best test for diagnosing ITB Friction Syndrome is ultrasound. Ultrasound scanning uses a probe that is passed over the skin, exactly the same as for a pregnancy scan. Ultrasound can look at the ITB as it passes over the lateral epicondyle whilst the knee is moving, and with the Doppler effect turned on any inflammation will show up very clearly as multiple red dots on the screen. If you are going to have an ultrasound scan for suspected ITB Friction Syndrome then it is a good idea to exercise in advance, specifically to make your knee as symptomatic as possible at the time of the actual scan, to increase the sensitivity and pick-up rate of the scan.

What’s the treatment of ITB Friction Syndrome?

The first line treatment for ITB Friction Syndrome should consist of:-

• Rest and avoidance of whatever specific exercises aggravate the symptoms
• Anti-inflammatory tablets, such as nurofen
• Exercises to stretch out the ITB
• Application of / massage with a foam roller, pressed against the ITB
• Assessment and correction of any biomechanical issues in the leg, for example strengthening of the gluteal muscles or correction of poor foot posture
• Other techniques such as acupuncture may also help improve symptoms

The best person by far for giving and supervising the conservative (non-surgical) treatment of ITB Friction Syndrome is a registered Physiotherapist.

2nd line treatment:

Ultrasound-guided steroid injections If a patient has already tried the above measures but their symptoms have persisted, then the next step up is to have an ultrasound-guided steroid/cortison injection under the distal ITB, at the side of the knee.

‘Steroid’ and ‘cortisone’ mean the same thing. Many people are concerned as soon as they hear the word ‘steroid’. However, the steroid that is used for these kinds of injections is not an anabolic steroid, like some body-builders use. Also, all the nasty side effects that one hears of with the use of steroids such as fluid retention or weakening of the bone are associated with high dose intravenous steroid, for things such as major head injuries, or long courses of steroid tablets for problems such as auto-immune diseases. The small dose of steroid that is injected in or around knees does not have any significant effect on the rest of the body, but simply acts locally as a very potent anti-inflammatory, like a massive dose of nurofen all in one spot. It can take anything up to 48 hours or sometimes even a week or two for the full effects of a steroid injection to kick in, but normally the injection is very effective, particularly when combined with all the other non-surgical measures listed above.

Giving the steroid injection under ultrasound guidance is the gold standard way to give a steroid injection as 1) the ultrasound scan first actually confirms the suspected diagnosis, and 2) the person perfoming the ultrasound scan (either a Consultant Sports Physician or a Consultant Radiologist specializing in MSK radiology) can then watch to see that the tip of the needle actually goes into exactly the correct spot, so that you can be sure that the injection is actually given into the right place, precisely.

Ultrasound guided steroid injections combined with physio treatments have a very good chance of completely curing ITB Friction Syndrome. If an injection cures or even partly cures a patient’s symptoms but with time the symptoms then start to recur, and if they are bad enough, then if necessary the ultrasound-guided injection can be repeated (normally no sooner than 6 weeks or so after any first injection). If a patient then still has ongoing symptoms/restrictions and if they are bad enough, then if necessary one might need to consider surgical treatment.

3rd line treatment:

Surgical ITB Release/Decompression If a patient has had appropriate physio treatments and if they’ve tried ultrasound guided steroid injection(s) but their symptoms persist and if any ongoing symptoms and functional restrictions are actually bad enough to justify it then it might potentially be necessary to consider surgical treatment, with an ITB release. ITB release and ITB decompression mean the same thing, and there are a number of different ways, technically, to perform this surgery – all of which basically involve the same thing, which is to release/lengthen the ITB to take some of the tension out of it, in order to stop the ITB rubbing so hard on the lateral epidcondyle.

The technique that I personally prefer is that promoted by some American surgeons, and involves just a small incision on the outer side of the knee under a brief general anaesthetic, with incision of the posterior 1cm – 1.5cm of the ITB (a partial incision). The tendinous ITB tissue ‘pings apart’, reducing some of the tension in the part of the ITB that is normally most responsible for causing the rubbing that leads to ITB Friction Syndrome. Patients can go home the same day and are able to fully weight bear straight away (although they may need crutches initially, for just the first day or two, just for comfort). I advise patients to then just ‘potter around’ and take things easy for the first 10 days or so post-op before then recommencing physio treatments again, and I advise people to avoid any running until 6 weeks post-op at the very earliest (depending on how they get on with their physio rehab).

Surgical ITB release is a small, safe, simple operation with very high success rates (90+%). However, obviously it’s always best to avoid surgery whenever possible, and thankfully surgical ITB release is rarely actually ever needed nowadays, because the various non-surgical treatments work so well.