Runner's knee, also known as iliotibial band syndrome (ITBS), is a common issue among athletes, especially runners, cyclists, rowers, as well as basketball and soccer players, affecting the outer edge of the knee. Its prevalence varies depending on the sport; among recreational runners, it affects 12-52 percent, whereas among military personnel (in the USA), it ranges from 1-5 percent. The main symptom is pain localized around the outer part of the femoral condyle. The pain is typically sharp and intense enough to require a break from running. Running downhill and descending stairs often exacerbate the condition, and if left untreated, it may become more easily aggravated over time. The predictability of the condition is hindered by the limited amount of reliable research, but some studies suggest that about 50-90 percent of cases improve within 4-8 weeks. However, for some, the condition may recur. Overall, runner's knee remains somewhat of an enigma in the realm of science. (1,3,4)
Causes
Long believed to be caused by friction between various knee structures, runner's knee was thought to occur when the iliotibial band (also known as the IT band or iliotibial tract), a band of tissue on the outer side of the thigh, would rub over the lateral femoral condyle, leading to irritation in the area. However, research suggests that the iliotibial band is unable to perform such a movement, and with new research, the cause of runner's knee is now thought to involve compression rather than friction. Beneath the iliotibial band are various anatomical structures, such as fat pads and bursae, which can potentially cause pain through compression. This distinction between friction and compression is significant, as previously, stretching the band was thought to alleviate pain. However, stretching may not be the best treatment option, and it does not affect the structure of the band in any way, despite popular belief. Ultimately, the condition usually arises from excessive loading, such as sudden increases in training volume, changes in running surface, or abrupt changes in footwear. It has also been suggested that weakness in the hip abductor muscles may be associated with the condition. (1,2,3)
IT band anatomy and function
As the name suggests, the iliotibial band (IT band) is a very strong, fascial structure that originates from the crest of the ilium (known as the crista iliaca) and attaches to the lateral condyle of the tibia at a bony prominence called Gerdy's tubercle (tuberculum Gerdy’s). The band is largely composed of type 1 collagen, a protein, and elastin, a protein that increases tissue elasticity. The IT band crosses both the hip and knee joints. At its upper end, the band receives fibers from the gluteus maximus muscle and the tensor fasciae latae muscle.
Currently, researchers still debate the anatomy and function of the IT band. Variations in origin and insertion points among individuals contribute to these uncertainties, affecting its functions.
Although there is still much uncertainty surrounding the functions of the band, we know that it is capable of adapting and transferring forces between different parts of the body. Interestingly, IT bands in humans develop only when we begin to walk and run. Other functions are believed to include hip extension, hip abduction, hip external and internal rotation, knee extension, and knee flexion when the knee flexion angle exceeds approximately 30 degrees. It is also important to remember that a "tight" feeling IT band is usually a normal occurrence and may even be beneficial. (1,4,5)
How is it diagnosed?
Interview - often there is some kind of change in training, the location and intensity of pain must also be determined.
Clinical examination - especially the function of the hips, knees, and ankles is examined, the painful area is palpated by hand, muscle strength levels are tested.
Imaging is usually not needed - sometimes other conditions may need to be ruled out.
Management
While there is still a need for much more research on the treatment of runner's knee, generally, load management and various strength exercises are recommended. It may also be necessary to modify running technique. In rehabilitation, the focus is often initially on reducing the training load slightly to calm the painful knee. However, complete rest is rarely necessary. Corticosteroid injections may also alleviate symptoms for some individuals. Rehabilitation programs typically emphasize strengthening exercises for the hip and knee. The benefits of manual therapy have conflicting research evidence. Some patients, however, find benefit from treatments such as massage, but it should not be the sole treatment for runner's knee. Nowadays, many also believe that "rolling" the IT band, for example, with a foam roller, is essential to maintain its health. While rolling can be done if it is enjoyable (it is unlikely to cause harm and may temporarily alleviate pain), it cannot be considered a highly effective treatment or preventive measure for runner's knee or any other musculoskeletal disorder. Rolling does not affect the anatomical structure of the band, although it may feel like it does.
If you are experiencing knee pain, seek the help of a skilled professional as soon as possible. This allows problems to be addressed at an early stage, and often leads to faster recovery.
What is runner's knee?
Runner's knee is typically a stress-related pain condition on the outer edge of the knee. The pain is caused by structures beneath the lateral fascia of the thigh.
Treatment for runner's knee
Rehabilitation for runner's knee
Recovery time for runner's knee
Is knee support beneficial?
Ilari Keckman
Osteopath, sports massage therapist & educator
Joonas Virtanen
Osteopath, sports massage therapist & physical trainer
References
5. https://www.ncbi.nlm.nih.gov/books/NBK537097/
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