Posterior Tibial Tendon Dysfunction (PTTD)

 

The posterior tibial tendon (PTT) is a vital structure in proper foot function.  Failure of the PTT to properly function can occur due to disease in the tendon or from excessive stress to the tendon.  Regardless of the cause, once the PTT no longer functions as it should, it often causes a great deal of discomfort and limitation of normal foot function.

Anatomy

The PTT begins in the calf and extends down the leg and around the base of the inner ankle to attach to the underside of almost every bone in the middle of the foot.  The primary attachment is on the bones supporting the arch of the foot. It is an essential structure that maintains the bones in their proper position.  The PTT is different than the other muscles and tendons that are in the same region because the portion of the tendon below the ankle receives very little blood supply.

Symptoms

Dysfunction of this tendon can produce pain and swelling if the tendon is damaged through sudden increased activity, direct injury, or as the result of a medical condition.  The condition can include swelling and warmth around the inner-middle foot or ankle. These symptoms can last from weeks to months.

Dysfunction that develops over a long period of time may not result in significant pain and swelling.  The only indication of impaired function may be changes in the appearance of the foot.  As this tendon provides support to the arch of the foot, PTTD can present as a decrease or loss of the arch.  This will cause the foot to flatten out and even appear to be rotated inwards.  Long periods of exercise or standing may cause discomfort and exhaustion.  

Causes

Most of the causes of PTTD are from long-term degeneration and injury of the tendon.  Diseases like rheumatoid arthritis can cause constant inflammation of the tendon over a long period of time.  This can lead to weakening of the tendon and can eventually result in tearing of the tendon.  Uncontrolled infections such as tuberculosis or gonorrhea can cause inflammation of the tendon leading to PTTD as well.

As mentioned earlier, the PTT has an area with limited blood supply.  Previous steroid use, obesity, chronic high blood pressure, diabetes, and old age can all cause a decrease in the amount of blood flow to the tendon. If the tendon’s blood supply becomes to low it will no longer receive enough nutrients and oxygen, the tendon then begins to degenerate and weaken.  Weakening of the PTT from lack of proper blood supply will lead to dysfunction.

Simple overuse of the PTT can also lead to tendon dysfunction.  Individuals who are extremely overweight or have a low arch in their foot can exert a large amount of stress on the tendon.  Sudden tearing of the tendon from overuse is very rare.  However, overuse can cause inflammation of the tendon and eventually lead to a tendon tear, which in turn will cause improper tendon function.      

Direct cuts and puncture wounds (something piercing through the skin) to the inner ankle can cause injury of the tendon, but surprisingly tearing of the tendon occurs more often with ankle sprains and fractures.  Injury of the lower back, resulting in nerve damage, can also cause PTTD.

Physical Exam

When a foot is being evaluated for PTTD both the appearance and function of the foot must be taken into account.  Appearance of the foot should be assessed with the patient both sitting and standing.  If PTTD is present, the arch of the foot will be decreased or absent while the patient is standing.  In early PTTD, a normal arch might be observed while the patient is not placing weight on the problematic foot.  The foot may present with more deformities when the tendon dysfunction has been present for a long time.

“Too many toes” sign is linked to PTTD and loss of the normal appearance of the foot.  When viewing a normal foot from directly behind the patient, only the fifth toe and a portion of the fourth toe should be visible.  In patients with tendon dysfunction the foot will tend to turn out as the arch collapses inwards, causing more toes to be visible from behind.

The motion of the ankle and joints of the foot can also be affected.  Over time arthritis can develop in the joints of the foot due to abnormal function with PTTD.   Arthritic changes in the joints can lead to decreased or painful motion in the foot.

While the patient is seated, the strength of the PTT is gaged by having the patient hold their foot with the toes pointing toward the floor and the foot turned inward.  The physician will then place force against the foot, attempting to move it back to a resting position.  Decreased ability to hold the foot’s position is a sign of PTTD.

A Single Heel Raise Test can also be used to evaluate PTTD.  The patient is first asked to stand and then rise on their toes.  Normally the heels should rotate slightly inward as the patient rises to their toes.  The patient may also be asked to stand on one leg and rise to their toes.  This should exaggerate the slight inward rotation of the heel.  If the patient shows decreased heel rotation, or is unable to rise to their toes it is a sign of PTTD.

Diagnostic Studies:

X-rays are used to assess any boney changes, adaptations, or variations that may have aggravated or resulted from the PTTD.  These x-rays are taken with the patient weight bearing and include several views of the affected foot.  An MRI is used to view the tendon and associated non-boney structures of the foot in order to assess the severity of the inflammation and destructive changes.

Non-Surgical Treatment

Symptoms can be relieved through limiting or stopping activities that produce pain and icing the painful region. Orthopedic shoes, orthotic shoe inserts, padding, footwear changes, and bracing may be used to help patients who have limited PTTD.  Over-the-counter (OTC) anti-inflammatory medications, such as Ibuprofen, can be used to help reduce pain and swelling.

Injection of platelet rich plasma is an emerging technology which is also used to treat the involved tendon.

Surgical Treatment

Surgery may be required if the PTTD discomfort and related disability cannot be relieved with non-surgical treatment.  The goal of surgery is to relieve pain and/or re-establish stability in the arch of the foot and provide better function.  The degree of PTTD is assessed by combining all of the findings from the physical exam and diagnostic studies to determine the condition of the tendon and the state of the associated bone structures.  The level and type of surgery needed is then determined by the amount of flexibility in the foot, and damage to the boney structures and the PTT.

Tears in the PTT may be repaired directly.  Direct tendon repair can involve cleaning out the inflamed tissue or reinforcing the PTT with another tendon from the same region.  The bones may be cut and shifted to correct any changes or damage that has occurred from improper movement and to restore the arch.  If the deformity is severe, it may be necessary to unite or fuse some of the joints in the foot.  Although fusion can limit mobility, it will decrease the pain experienced when walking and halt the deformity from causing more damage. 

 

Source Material

Mahan, Kieran T; Flanigan, Paul K. Tibialis Posterior Tendon Dysfunction. In: Banks, A., Downey, M., Martin, D., Miller, S., eds. McGlamry’s Comprehensive Textbook of Foot and Ankle Surgery. Philadelphia, Pa: Lippincott Williams and Wilkins; 2001: 862-899

Pomeroy, Gregory C; Pike, R. Howard; Beals, Timothy C; Manoli, Arthur.  Current Concepts Review: Acquired Flatfoot in Adults Due to Dysfunction of the Posterior Tibial Tendon.  JBJS 1999, 81-A(8), 1173 – 1182

 

Posterior Tibial Tendon Dysfunction (PTTD)

The posterior tibial tendon (PTT) is a vital structure in proper foot function.  Failure of the PTT to properly function can occur due to disease in the tendon or from excessive stress to the tendon.  Regardless of the cause, once the PTT no longer functions as it should, it often causes a great deal of discomfort and limitation of normal foot function.

Anatomy

The PTT begins in the calf and extends down the leg and around the base of the inner ankle to attach to the underside of almost every bone in the middle of the foot.  The primary attachment is on the bones supporting the arch of the foot. It is an essential structure that maintains the bones in their proper position.  The PTT is different than the other muscles and tendons that are in the same region because the portion of the tendon below the ankle receives very little blood supply.

Symptoms

Dysfunction of this tendon can produce pain and swelling if the tendon is damaged through sudden increased activity, direct injury, or as the result of a medical condition.  The condition can include swelling and warmth around the inner-middle foot or ankle. These symptoms can last from weeks to months.

Dysfunction that develops over a long period of time may not result in significant pain and swelling.  The only indication of impaired function may be changes in the appearance of the foot.  As this tendon provides support to the arch of the foot, PTTD can present as a decrease or loss of the arch.  This will cause the foot to flatten out and even appear to be rotated inwards.  Long periods of exercise or standing may cause discomfort and exhaustion.  

Causes

Most of the causes of PTTD are from long-term degeneration and injury of the tendon.  Diseases like rheumatoid arthritis can cause constant inflammation of the tendon over a long period of time.  This can lead to weakening of the tendon and can eventually result in tearing of the tendon.  Uncontrolled infections such as tuberculosis or gonorrhea can cause inflammation of the tendon leading to PTTD as well.

As mentioned earlier, the PTT has an area with limited blood supply.  Previous steroid use, obesity, chronic high blood pressure, diabetes, and old age can all cause a decrease in the amount of blood flow to the tendon. If the tendon’s blood supply becomes to low it will no longer receive enough nutrients and oxygen, the tendon then begins to degenerate and weaken.  Weakening of the PTT from lack of proper blood supply will lead to dysfunction.

Simple overuse of the PTT can also lead to tendon dysfunction.  Individuals who are extremely overweight or have a low arch in their foot can exert a large amount of stress on the tendon.  Sudden tearing of the tendon from overuse is very rare.  However, overuse can cause inflammation of the tendon and eventually lead to a tendon tear, which in turn will cause improper tendon function.      

Direct cuts and puncture wounds (something piercing through the skin) to the inner ankle can cause injury of the tendon, but surprisingly tearing of the tendon occurs more often with ankle sprains and fractures.  Injury of the lower back, resulting in nerve damage, can also cause PTTD.

Physical Exam

When a foot is being evaluated for PTTD both the appearance and function of the foot must be taken into account.  Appearance of the foot should be assessed with the patient both sitting and standing.  If PTTD is present, the arch of the foot will be decreased or absent while the patient is standing.  In early PTTD, a normal arch might be observed while the patient is not placing weight on the problematic foot.  The foot may present with more deformities when the tendon dysfunction has been present for a long time.

“Too many toes” sign is linked to PTTD and loss of the normal appearance of the foot.  When viewing a normal foot from directly behind the patient, only the fifth toe and a portion of the fourth toe should be visible.  In patients with tendon dysfunction the foot will tend to turn out as the arch collapses inwards, causing more toes to be visible from behind.

The motion of the ankle and joints of the foot can also be affected.  Over time arthritis can develop in the joints of the foot due to abnormal function with PTTD.   Arthritic changes in the joints can lead to decreased or painful motion in the foot.

While the patient is seated, the strength of the PTT is gaged by having the patient hold their foot with the toes pointing toward the floor and the foot turned inward.  The physician will then place force against the foot, attempting to move it back to a resting position.  Decreased ability to hold the foot’s position is a sign of PTTD.

A Single Heel Raise Test can also be used to evaluate PTTD.  The patient is first asked to stand and then rise on their toes.  Normally the heels should rotate slightly inward as the patient rises to their toes.  The patient may also be asked to stand on one leg and rise to their toes.  This should exaggerate the slight inward rotation of the heel.  If the patient shows decreased heel rotation, or is unable to rise to their toes it is a sign of PTTD.

Diagnostic Studies:

X-rays are used to assess any boney changes, adaptations, or variations that may have aggravated or resulted from the PTTD.  These x-rays are taken with the patient weight bearing and include several views of the affected foot.  An MRI is used to view the tendon and associated non-boney structures of the foot in order to assess the severity of the inflammation and destructive changes.

Non-Surgical Treatment

Symptoms can be relieved through limiting or stopping activities that produce pain and icing the painful region. Orthopedic shoes, orthotic shoe inserts, padding, footwear changes, and bracing may be used to help patients who have limited PTTD.  Over-the-counter (OTC) anti-inflammatory medications, such as Ibuprofen, can be used to help reduce pain and swelling.

Injection of platelet rich plasma is an emerging technology which is also used to treat the involved tendon.

Surgical Treatment

Surgery may be required if the PTTD discomfort and related disability cannot be relieved with non-surgical treatment.  The goal of surgery is to relieve pain and/or re-establish stability in the arch of the foot and provide better function.  The degree of PTTD is assessed by combining all of the findings from the physical exam and diagnostic studies to determine the condition of the tendon and the state of the associated bone structures.  The level and type of surgery needed is then determined by the amount of flexibility in the foot, and damage to the boney structures and the PTT.

Tears in the PTT may be repaired directly.  Direct tendon repair can involve cleaning out the inflamed tissue or reinforcing the PTT with another tendon from the same region.  The bones may be cut and shifted to correct any changes or damage that has occurred from improper movement and to restore the arch.  If the deformity is severe, it may be necessary to unite or fuse some of the joints in the foot.  Although fusion can limit mobility, it will decrease the pain experienced when walking and halt the deformity from causing more damage. 

 

Source Material

Mahan, Kieran T; Flanigan, Paul K. Tibialis Posterior Tendon Dysfunction. In: Banks, A., Downey, M., Martin, D., Miller, S., eds. McGlamry’s Comprehensive Textbook of Foot and Ankle Surgery. Philadelphia, Pa: Lippincott Williams and Wilkins; 2001: 862-899

Pomeroy, Gregory C; Pike, R. Howard; Beals, Timothy C; Manoli, Arthur.  Current Concepts Review: Acquired Flatfoot in Adults Due to Dysfunction of the Posterior Tibial Tendon.  JBJS 1999, 81-A(8), 1173 – 1182