Article Review: Understanding the IT band | Harvard Gazette

Link: Understanding the IT band | Harvard Gazette

Fig. 1, From Netter's
Atlas of Anatomy

Linked above is an article that summarizes some interesting research about the elastic qualities of the iliotibial band (IT band or ITB). This fascial structure connects the lateral hip with the lateral knee. The gluteus maximus attaches directly into the IT band, as does the tensor fascia lata (TFL) muscle. This structure can be involved with many pain patterns, including IT band friction syndrome, about which I posted recently. This post will explore the content of the Harvard Gazette article through the perspective of the Stomach and Gallbladder sinew channels.

Fig. 2, From Netter's
Atlas of Anatomy

The research shows that the IT band stores and releases elastic energy during walking or running, which makes these activities more efficient. Running, in particular, was shown to take advantage of this elastic recoil. The 'recycled energy' gained from elastic recoil is due to the fact that the IT band connects to the front of the pelvis through the TFL attachment (ASIS and anterior iliac crest) and the back of the pelvis through the gluteus maximus (primarily the sacral attachments and PSIS) (fig. 1). During extension, the anterior line of ITB through the TFL to the front of the pelvis is stretched, and the energy being released propels the limb forward. The posterior line of the ITB through the gluteus maximus to the posterior pelvis is then stretched as the limb is flexed, thus building tension and storing energy to assist with extension. A pretty remarkable system of energy storage and conservation is therefore created and used!

For acupuncturists, especially Sports Medicine Acupuncturists like me, there is an opportunity to examine this dynamic with respect to the sinew channels. I believe this involves the Gallbladder sinew channel and the Stomach sinew channel (or at least a branch of the Stomach sinew channel).

Fig 3: Gallbladder Sinew Channel
from A Manual of Acupuncture, by
Peter Deadman

Gallbladder Sinew Channel: This involves the attachments of the extensor digitorum longus into the ITB, which, in my clinical experience, communicates primarily with the gluteus maximus attachment (fig. 2 and 3). One might also consider the peroneus longus, but I feel this is more properly assigned to a branch of the Urinary Bladder sinew channel which connects into the biceps femoris and affects sacroiliac joint balance during gait. But that is beyond the scope of this discussion (see fig. 5).

Fig 4: Stomach Sinew Channel
from A Manual of Acupuncture

Stomach Sinew Channel: This involves the attachment of the tibialis anterior into the ITB which, in my clinical experience, communicates primarily with the TFL. Note that the ST sinew channel does involve the tibialis anterior and anterior crural fascia attaching into the quadriceps (mainly rectus femoris and vastus lateralis). But I believe the ITB-TFL connection to be a branch of the ST sinew channel (fig. 2 and 4), as depicted in Deadman's A Manual of Acupuncture and described in the Ling Shu: "A branch goes along the leg bone and joins the Leg Shaoyang..." (translation from Jingjin, by David Legge).

Fig. 5: Urinary Bladder sinew
channel From A Manual of Acupuncture.
Note the side branch on the leg, which I 
interpret as the peroneus longus; 
this connects to the biceps femoris 
and is not part of this discussion.

So, proper balance and efficiency in walking and running is partially achieved through the relationship of the Stomach sinew channel and the Gallbladder sinew channel. This gives new insight into Zusanli ST-36 (Leg Three Miles) which is one of two motor points of the tibialis anterior. The TFL is very often overactive, as seen in Ober's test. Could needling the motor point of the tibialis anterior at ST-36 allow for better range of motion through this tibialis anterior-ITB-TFL connection, allowing for better extension and creating more stored energy? It sounds like classical thought was on to something in stating "that stimulating Zusanli ST-36 would enable a person to walk a further three li, even when exhausted." (from A Manual of Acupuncture).

I encourage you to check out the original article; there is a great animation to visualize the elastic recoil I mentioned.

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Iliotibial Band Friction Syndrome: A Common Cause of Lateral Knee Pain

Iliotibial Band with Highlighted Area of Pain.
From An Atlas of Human Anatomy by,
Carl Toldt, M.D.

Iliotibial band friction syndrome is one of the most common cause of lateral knee pain and is especially prevalent with runners. In iliotibial band friction syndrome the iliotibial band (ITB), which is a thick connective tissue structure on the outside (lateral) portion of the thigh, rubs up against the expanded end of the femur (thigh bone). This rubbing occurs at about 30^o of knee flexion. Over time, the ITB becomes irritated and can become a cause of pain when running; this can even become chronic, causing pain at rest.

Understanding the mechanism of injury helps when determining how to treat this common cause of knee pain. Many people will state that a ‘tight’ ITB is the cause; actually, this is somewhat incorrect. First, the ITB is not a muscle and is not contractible, at least compared to a muscle. Second, it is most often the case that the ITB is taut in ITB friction syndrome. What I mean by this is that the ITB is often pulled into an overlengthened position.

To understand this, it is important to understand the role of the gluteus medius and minimus in pelvic stability. During the weight bearing phase of the gait cycle, these muscles fire to prevent an excessive rising of the ilium. If you were to place your hands on your waist and press down until you feel bone, you would be on the ilium. When walking (or running), during the weight bearing portion, this bone should not rise too much. The gluteus medius and minimus are the muscles most responsible for creating this stability. If these muscles become inhibited and lose the ability to stabilize the pelvis, it then will rise excessively and structures such as the ITB will be pulled long with each step. To help visualize this, you can consider that women naturally have more pelvic movement and some women (Marilyn Monroe, historically, and many runway models) actually practice exaggerating this movement for aesthetic reasons.

In the majority of the cases, the side where ITB friction syndrome occurs is also the side where the greatest degree of inhibition of the gluteus medius and minimus occurs. This can be assessed with manual muscle tests which challenge these muscles. In addition, most patients presenting with ITB friction syndrome will have a raised ilium when assessing standing posture, and this raised ilium will be on the side of the lateral knee pain.

Treatment of ITB friction syndrome needs to include some work to strengthen the gluteus medius and minimus for optimum results. Things like foam rolling the ITB might help to soften it, but most often work needs to be on the short and tight adductors on the inside of the leg, and strengthening corrective exercises should be applied to the abductors such as the gluteus medius and minimus.

Acupuncture can be extremely helpful as part of the therapy. Acupuncture to motor points (approximately in the region of the entry site of the motor nerve into the muscle) can help turn on inhibited muscles, which is shown by the muscles strengthening after treatment when testing with manual muscle tests. In addition, acupuncture to motor points of the overactive antagonistic muscles (adductors in this case) will help reduce tension in these muscles. This helps strengthen the effects of corrective exercises and allows quicker recovery time so you can get back out and hit the trails.

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