Posterior Tibial Tendon Dysfunction

The posterior tibial tendon is responsible for support of the arch region. This tendon is placed under a great deal of stress with walking and can tear at times. The most common patient affected is a woman from 40 to 65 with flat feet. The constant pressure on the tendon without support can lead to a tear of the tendon and collapse of the arch. Posterior tibial tendon tears are often associated with flat feet or pes planus.

Picture showing bilateral severe flat foot due to PTTD,
posterior tibial tendon dysfunction.

The ideal therapy for posterior tibial tendon problems is to treat the issue early. If the problem is caught prior to a tear in the tendon, orthotic therapy can be used to correct the poor foot position and decrease pressure on the arch and tendon region. In some cases when the tendon is very weak and surgery in not warranted, special braces can be used to aid in a more functional gait. Physical therapy can also be used to decrease tendon inflammation and prevent further problems in the tendon pressure and tightness.

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Picture showing a functional foot orthotic supporting the arch. Picture showing a custom molded functional brace that will aid in function with a damaged posterior tibial tendon.

If the tendon tears, it is most likely to require surgery. If surgery is not done, the foot will continue to collapse in the arch region and arthritis can develop. Repair of the torn tendon when there is little collapse will require using stitches to close the tear, then using coblation Topaz therapy around the rest of the damaged tendon. In some cases the tendon will need to be re-attached to the main bone (navicular) to take out the “slack” in the tendon. This is done with tendon anchors to the bone.

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Picture showing the PT tendon widened and flattended. Picture showing the Topaz probe making holes into the tendon to encourage the tendon to heal.
Picture showing the tendon with fenestrations after coblation treatment with the Topaz probe.

In many cases there is an extra bone (accessory ossicle or os tibiale externum) that lies next to the main navicular bone and is embedded within the posterior tibial tendon. This bone is usually partially detached from the main bone, becoming a source of pain and debilitation as the tendon constantly pulls on the bone fragment. Often times, this bone needs to be removed.

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X-ray showing accessory (extra) bone that lies within the Posterior Tibial Tendon, often contributing to increased pain and irritation to the tendon. X-ray showing surgical correction after removing the accessory bone, taking up the slack off the tendon and anchoring it back into its bone insertion.
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Picture showing the bone ossicle separated from the main navicular bone and the tendon partially detached. Picture showing the forceps grabbing the loose bone.
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Picture of the bone ossicle removed from the foot. Picture showing the foot without the bone ossicle.
Picture of the posterior tibial tendon being prepared to be anchored back into the navicular bone.

When the tendon becomes too weak to support itself, often times it need the extra support of another tendon. Using half of an adjacent tendon, a transfer is done to recreate a stable posterior tibial tendon.

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Picture showing damaged PT tendon. Notice the healthy tendon just below the PT. This tendon will be used for the transfer. Picture showing the harvesting of the tendon that will be transferred. The cut end of the tendon is in the forceps.
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Picture showing the drill hole being made into the bone of the arch in order to anchor the tendon into the bone. Picture showing the implant used to anchor the transferred tendon into the bone.
Picture showing the completed transfer of the tendon. The new tendon is at the arrow’s tip.

There are times when simple repair of the tendon is not enough to support the fallen arch. A correction of the pes planus (flat feet) will need to be performed as well. These may include moving the heel bone, or fusing of one or two joints and possible lengthening of a tight Achilles tendon that is placing extra stress on the arch area. If additional procedures to stabilize the foot are necessary, a complete therapeutic program is set up for correction of the painful foot and ankle. The ultimate goal of the surgery is to place the foot in a stable position and decrease the pain of the region.

X-ray showing a flat foot. Notice the angles of the deformity with the relationship of the bones with each other. In the upper x-ray, the heel bone is angled too close to the ground. The ankle bone is angled too much towards the ground. In the Lower x-ray, the ankle bone is angled too far from the center of the 2nd toe and the center of the foot.
X-ray showing a flat foot after reconstruction. Notice the angles of the deformity with the relationship of the bones with each other. In the upper x-ray, the heel bone is now angled farther away from the ground. The ankle bone is now angled less towards the ground. In the Lower x-ray, the ankle bone is now angled closer to the center of the 2nd toe and the center of the foot.