Iliotibial Tract

Original Editor - Eman Ammar

Top Contributors - Eman Ammar and Lucinda hampton

Description

The iliotibial band (ITB) is a thick band of fascia formed proximally at the hip by the fascia of the gluteus maximus, gluteus medius and tensor fasciae latae muscles.

• The ITB runs along the lateral thigh and serves as an important structure involved in lower extremity motion.
• There are multiple clinical conditions that can present secondary to a spectrum of ITB dysfunction  eg external snapping hip syndrome, ITB syndrome. 

Image 1: The iliotibial band (ITB). is a thick band of fascia formed proximally at the hip by the fascia of the gluteus maximus, gluteus medius and tensor fasciae latae muscles.

1. Due to the ITBand’s insertion on Gerdy’s tubercle, it actually has no bony attachment along the femur. Therefore, it has the tendency to shift anterior/posterior (front to back) as your knee flexes and extends.
2. The Iliotibial Band is made up of mostly collagen fibers. Collagen is a protein, the strongest protein found in nature. The collagen fibres are aligned in a very organized, vertical fashion as this allows for better force absorption with weight bearing activities. There is a small amount of elastin fibers amongst the layers of collagen, which allow it to be slightly elastic and pliable helping it act as a spring. However, this does not give it the ability to “stretch” or “change length” like a muscle.

Anatomy

The iliotibial band (ITB) is a thick band of fascia formed proximally at the hip by the fascia of the gluteus maximus, gluteus medius and tensor fasciae latae muscles.

The band consists of deep and superficial layers insertions are:

1. The superficial layer is the main tendinous component and inserts onto Gerdy's tubercle on the anterior lateral tibia
2. The deep layer inserts on the intermuscular septum of the distal femur

A small recess exists between the lateral femoral epicondyle and the ITB, which contains a synovial extension of the knee joint capsule (lateral synovial recess)

The ITB shares the innervation of the TFL and gluteus maximus via the superior gluteal nerve and inferior gluteal nerve

Function.

Proximal ITB function includes:

1. Hip extension
2. Hip abduction
3. Lateral hip rotation

Distally, ITB function depends on the position of the knee joint

1. Full extension to 20 to 30 degrees of flexion: Active knee extensor, ITB lying anterior to the lateral femoral epicondyle
2. 20 to 30 degrees of flexion to full flexion ROM: Active knee flexor, ITB lies posterior relative to the lateral femoral epicondyle

Physiotherapy

The iliotibial band is one of the most common running injuries we see as physiotherapists. It is considered a non-traumatic overuse injury and is often concomitant with underlying weakness of hip abductor muscles. For more see Iliotibial Band Syndrome. Clinical examination testing for ITB dysfunction is best elicited utilizing the Ober Test, see here

External snapping hip syndrome is another ITB pathology you may encounter. Snapping Hip Syndrome is a condition that is characterized by a snapping sensation, and/or audible “snap” or “click” noise, in or around the hip when it is in motion.