Function of the posterior tibialis muscle
The functions of the muscle result mainly from the position and course of the muscle and its attachment tendon. The attachment tendon runs as already described rather on the back of the upper ankle joint toward the foot and starts at the lower side of the bones there. This results in a contraction and a shortening of the muscle belly, which causes the tip of the foot to move away from the body as when walking on tiptoe.
This is also known as plantar flexion. Since the attachment tendon also passes the lower ankle joint in the middle of the ankle, the sole of the foot is lifted towards the middle when the muscle contracts. This process is also known as supination or inversion.
Isolated movement of the upper or lower ankle joint when using the M. tibialis posterior is generally not possible, since the muscle always performs both functions when contracting. Only the interaction of several muscles allows isolated plantar flexion or isolated supination. Since a person’s weight actually always pulls on the insertion tendon, it also causes tension in both arches of the foot. The tendon runs along the sole of the foot both slightly transversely and slightly obliquely in relation to the body axes and can thus stabilize both arches.
Diseases of the M. tibialis posterior
Inflammation of the tendon can manifest itself in several ways and have various causes. In the case of an inflammation, the tendon sheath in the malleolar canal is usually also affected. The most common cause of inflammation of the tendon of the posterior tibialis muscle is overloading.
Too frequent execution alone can be the deciding factor here. However, even minimal incorrect posture during constantly repeated movements can cause minor injuries to the tendon and tendon sheath. Typically, such overloading occurs in athletes.However, long uphill walking can also be a cause.
Other possible causes are an infection or an immunological reaction of the body. Such an inflammation becomes noticeable by permanent pain in the muscle area. In addition, swelling and permanent pulling can also be present.
Later on, the strength of the muscle is reduced, making it difficult to stand on tiptoe. Furthermore, a permanent inflammation can lead to malpositioning of the foot or tearing of the tendon, so that the clinical picture should always be treated. Usually the diagnosis is made on the basis of a clinical examination.
If necessary, imaging such as MRT can be used. An anti-inflammatory drug (NSAID) should be taken for treatment. You can find more detailed information on this topic at Inflammation of the tendon in the leg and inflammation of the tibialis posterior tendonThe causes of a rupture of the tendon are usually chronic degeneration of the tissue.
However, the rupture is perceived as an acute, very painful event. Furthermore, a rupture of the tendon can occur as a result of inflammation of the tendon. A traumatic event such as a broken bone or a cut can also lead to a rupture.
Since degeneration is the most common cause, a rupture of the tendon usually does not occur in young athletes but in older adults. Typical signs of a rupture are sudden pain in the inner ankle. Often this is the result of a twisting of the tendon.
In addition, it can be difficult to keep your balance and run on uneven ground. Furthermore, a malposition of the foot can occur. The diagnosis is made on the basis of a clinical examination and conservatively treated with insoles for the shoes over several months.
In serious cases, surgery can be performed to reattach the tendon ends. Are you more interested in this topic?
