Overview
The adult acquired flatfoot (AAF) is a progressive, symptomatic (painful) deformity resulting from gradual stretch (attenuation) of the tibialis posterior tendon as well as the ligaments that support the arch of the foot. Although the posterior tibialis tendon plays a significant role, this pathology has recently been recognized as involving failure of other interosseous ligaments, such as the spring ligament. Due to the complexity of this pathology, posterior tibial tendon dysfunction (PTTD) is now referred to as adult acquired flatfoot. Severe flatfoot associated with AAF can lead to other problems, such as plantar fascial tension, tendon pain, rearfoot subluxation, and ankle osteoarthritis.
Causes
There are numerous causes of acquired adult flatfoot, including fracture or dislocation, tendon laceration, tarsal coalition, arthritis, neuroarthropathy, neurologic weakness, and iatrogenic causes. The most common cause of acquired adult flatfoot is posterior tibial tendon dysfunction.
Symptoms
Pain along the inside of the foot and ankle, where the tendon lies. This may or may not be associated with swelling in the area. Pain that is worse with activity. High-intensity or high-impact activities, such as running, can be very difficult. Some patients can have trouble walking or standing for a long time. Pain on the outside of the ankle. When the foot collapses, the heel bone may shift to a new position outwards. This can put pressure on the outside ankle bone. The same type of pain is found in arthritis in the back of the foot. Asymmetrical collapsing of the medial arch on the affected side.
Diagnosis
The adult acquired flatfoot, secondary to posterior tibial tendon dysfunction, is diagnosed in a number of ways with no single test proven to be totally reliable. The most accurate diagnosis is made by a skilled clinician utilizing observation and hands on evaluation of the foot and ankle. Observation of the foot in a walking examination is most reliable. The affected foot appears more pronated and deformed compared to the unaffected foot. Muscle testing will show a strength deficit. An easy test to perform in the office is the single foot raise. A patient is asked to step with full body weight on the symptomatic foot, keeping the unaffected foot off the ground. The patient is then instructed to "raise up on the tip toes" of the affected foot. If the posterior tibial tendon has been attenuated or ruptured, the patient will be unable to lift the heel off the floor and rise onto the toes. In less severe cases, the patient will be able to rise on the toes, but the heel will not be noted to invert as it normally does when we rise onto the toes. X-rays can be helpful but are not diagnostic of the adult acquired flatfoot. Both feet - the symptomatic and asymptomatic - will demonstrate a flatfoot deformity on x-ray. Careful observation may show a greater severity of deformity on the affected side.
Non surgical Treatment
Because of the progressive nature of PTTD, early treatment is advised. If treated early enough, your symptoms may resolve without the need for surgery and progression of your condition can be arrested. In contrast, untreated PTTD could leave you with an extremely flat foot, painful arthritis in the foot and ankle, and increasing limitations on walking, running, or other activities. In many cases of PTTD, treatment can begin with non-surgical approaches that may include orthotic devices or bracing. To give your arch the support it needs, your foot and ankle surgeon may provide you with an ankle brace or a custom orthotic device that fits into the shoe. Immobilization. Sometimes a short-leg cast or boot is worn to immobilize the foot and allow the tendon to heal, or you may need to completely avoid all weight-bearing for a while. Physical therapy. Ultrasound therapy and exercises may help rehabilitate the tendon and muscle following immobilization. Medications. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, help reduce the pain and inflammation. Shoe modifications. Your foot and ankle surgeon may advise changes to make with your shoes and may provide special inserts designed to improve arch support.
Surgical Treatment
Until recently, operative treatment was indicated for most patients with stage 2 deformities. However, with the use of potentially effective nonoperative management , operative treatment is now indicated for those patients that have failed nonoperative management. The principles of operative treatment of stage 2 deformities include transferring another tendon to help serve the role of the dysfunctional posterior tibial tendon (usually the flexor hallucis longus is transferred). Restoring the shape and alignment of the foot. This moves the weight bearing axis back to the center of the ankle. Changing the shape of the foot can be achieved by one or more of the following procedures. Cutting the heel bone and shifting it to the inside (Medializing calcaneal osteotomy). Lateral column lengthening restores the arch and overall alignment of the foot. Medial column stabilization. This stiffens the ray of the big toe to better support the arch. Lengthening of the Achilles tendon or Gastrocnemius. This will allow the ankle to move adequately once the alignment of the foot is corrected. Stage 3 acquired adult flatfoot deformity is treated operatively with a hindfoot fusion (arthrodesis). This is done with either a double or triple arthrodesis - fusion of two or three of the joints in hindfoot through which the deformity occurs. It is important when a hindfoot arthrodesis is performed that it be done in such a way that the underlying foot deformity is corrected first. Simply fusing the hindfoot joints in place is no longer acceptable.
The adult acquired flatfoot (AAF) is a progressive, symptomatic (painful) deformity resulting from gradual stretch (attenuation) of the tibialis posterior tendon as well as the ligaments that support the arch of the foot. Although the posterior tibialis tendon plays a significant role, this pathology has recently been recognized as involving failure of other interosseous ligaments, such as the spring ligament. Due to the complexity of this pathology, posterior tibial tendon dysfunction (PTTD) is now referred to as adult acquired flatfoot. Severe flatfoot associated with AAF can lead to other problems, such as plantar fascial tension, tendon pain, rearfoot subluxation, and ankle osteoarthritis.
Causes
There are numerous causes of acquired adult flatfoot, including fracture or dislocation, tendon laceration, tarsal coalition, arthritis, neuroarthropathy, neurologic weakness, and iatrogenic causes. The most common cause of acquired adult flatfoot is posterior tibial tendon dysfunction.
Symptoms
Pain along the inside of the foot and ankle, where the tendon lies. This may or may not be associated with swelling in the area. Pain that is worse with activity. High-intensity or high-impact activities, such as running, can be very difficult. Some patients can have trouble walking or standing for a long time. Pain on the outside of the ankle. When the foot collapses, the heel bone may shift to a new position outwards. This can put pressure on the outside ankle bone. The same type of pain is found in arthritis in the back of the foot. Asymmetrical collapsing of the medial arch on the affected side.
Diagnosis
The adult acquired flatfoot, secondary to posterior tibial tendon dysfunction, is diagnosed in a number of ways with no single test proven to be totally reliable. The most accurate diagnosis is made by a skilled clinician utilizing observation and hands on evaluation of the foot and ankle. Observation of the foot in a walking examination is most reliable. The affected foot appears more pronated and deformed compared to the unaffected foot. Muscle testing will show a strength deficit. An easy test to perform in the office is the single foot raise. A patient is asked to step with full body weight on the symptomatic foot, keeping the unaffected foot off the ground. The patient is then instructed to "raise up on the tip toes" of the affected foot. If the posterior tibial tendon has been attenuated or ruptured, the patient will be unable to lift the heel off the floor and rise onto the toes. In less severe cases, the patient will be able to rise on the toes, but the heel will not be noted to invert as it normally does when we rise onto the toes. X-rays can be helpful but are not diagnostic of the adult acquired flatfoot. Both feet - the symptomatic and asymptomatic - will demonstrate a flatfoot deformity on x-ray. Careful observation may show a greater severity of deformity on the affected side.
Non surgical Treatment
Because of the progressive nature of PTTD, early treatment is advised. If treated early enough, your symptoms may resolve without the need for surgery and progression of your condition can be arrested. In contrast, untreated PTTD could leave you with an extremely flat foot, painful arthritis in the foot and ankle, and increasing limitations on walking, running, or other activities. In many cases of PTTD, treatment can begin with non-surgical approaches that may include orthotic devices or bracing. To give your arch the support it needs, your foot and ankle surgeon may provide you with an ankle brace or a custom orthotic device that fits into the shoe. Immobilization. Sometimes a short-leg cast or boot is worn to immobilize the foot and allow the tendon to heal, or you may need to completely avoid all weight-bearing for a while. Physical therapy. Ultrasound therapy and exercises may help rehabilitate the tendon and muscle following immobilization. Medications. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, help reduce the pain and inflammation. Shoe modifications. Your foot and ankle surgeon may advise changes to make with your shoes and may provide special inserts designed to improve arch support.
Surgical Treatment
Until recently, operative treatment was indicated for most patients with stage 2 deformities. However, with the use of potentially effective nonoperative management , operative treatment is now indicated for those patients that have failed nonoperative management. The principles of operative treatment of stage 2 deformities include transferring another tendon to help serve the role of the dysfunctional posterior tibial tendon (usually the flexor hallucis longus is transferred). Restoring the shape and alignment of the foot. This moves the weight bearing axis back to the center of the ankle. Changing the shape of the foot can be achieved by one or more of the following procedures. Cutting the heel bone and shifting it to the inside (Medializing calcaneal osteotomy). Lateral column lengthening restores the arch and overall alignment of the foot. Medial column stabilization. This stiffens the ray of the big toe to better support the arch. Lengthening of the Achilles tendon or Gastrocnemius. This will allow the ankle to move adequately once the alignment of the foot is corrected. Stage 3 acquired adult flatfoot deformity is treated operatively with a hindfoot fusion (arthrodesis). This is done with either a double or triple arthrodesis - fusion of two or three of the joints in hindfoot through which the deformity occurs. It is important when a hindfoot arthrodesis is performed that it be done in such a way that the underlying foot deformity is corrected first. Simply fusing the hindfoot joints in place is no longer acceptable.