Adult acquired flatfoot deformity – fallen arches and flat feet treatments

Ross Hauser, MD  | Caring Medical Regenerative Medicine Clinics, Fort Myers, Florida
Danielle R. Steilen-Matias, MMS, PA-C
 | Caring Medical Regenerative Medicine Clinics, Oak Park, Illinois
Katherine L. Worsnick, MPAS, PA-C  | Caring Medical Regenerative Medicine Clinics, Fort Myers, Florida
David Woznica, MD | Caring Medical Regenerative Medicine Clinics, Oak Park, Illinois

Adult acquired flatfoot deformity – fallen arches and flat feet treatments

There are many things that will cause adult acquired flatfoot deformity. This article will focus on how adult acquired flatfoot deformity is caused by structural damage to your supporting foot, ankle, and leg ligaments and tendons, with focus on the Posterior tibialis tendon and the spring ligament. We will explore surgical, non-surgical conservative care and regenerative medicine treatments.

If you are ready this article you probably do not need a description of what flat feet are, you can see it for yourself. The arch on the inside of your foot is flat and the sole of the foot rests on the ground. How did this happen? There could be many different factors. While obesity, diabetes, and generic factors are important in the development of some cases of flat feet, we are going to discuss wear and tear damage and injury.

The posterior tibialis tendon connects the calf muscles to the arch of the foot.  A lot of things can happen to a foot or a calf in the vulnerable to injury area.

If you are already seeking medical attention for problems of flat feet, it has probably already been explained to you that the main function of the posterior tibialis tendon is to hold up the arch of the foot and support the foot when walking. When there is injury to this tendon the arch is no longer supported. Injury to the Posterior tibialis tendon can be acute or the chronic wear and tear degenerative type injury.

If you have been injured in sport, a car accident, or a misstep or fall and you developed flat foot or flat feet, the acute injury cause makes a lot of sense to you. An obvious event occurred that damaged this tendon.

But what if the cause is wear and tear? This is a more challenging injury to understand.

Wear and tear injury does not happen in isolation. If your posterior tibialis tendon is frayed or damaged from years of sports, physical demanding work, or obesity, it is very likely that you have more issues than flat feet going on. In addition to experiencing pain in the lower legs where the tendon attaches to the calf muscle, the problems that you are encountering because of your flat feet  may show up in your hips, or ankles or knees. What else is showing up? Probably a lot of inflammation in your feet. As you will see, and probably experienced first hand, the initial medical plan for people with flat feet discomfort is to manage pain and functional loss with painkillers, anti-inflammatories, and shoe inserts. What you proabably are also experieicning first hand is that this is not working for you.

In 2015, doctors writing in the Journal of family medicine and primary care, (1) give a good outline of the paths of treatments a patient with flat feet can take. Here are their leaning points:

  • Degenerative changes in the Posterior tibial tendon will lead to pain and weakness and if not identified and treated will progress to deformity of the foot and degenerative changes in the surrounding joints.
  • Patients will complain of medial foot pain (pain near the arch), weakness, and a slowly progressive foot deformity. A “too many toes” sign (this is when you stand behind the patient and their foot is collapsing inward and forces the toes to point outward. You can see their toes from behind and it looks like they have “too many toes.”
  • Patients will be unable to perform a single heal raise test.
  • The optimal management of Posterior tibial tendon dysfunction may change based on the progression of deformity and stage of disease. Early identification and prompt initiation of treatment can halt progression of the disease.

The doctors then go about describing the various stages of the disease and the treatment options available to patients. These are the general recommendations for treatment, not necessarily our type of treatment.

Stage I disease

  • A walking cast or CAM (Controlled Ankle Motion) boot can be used to immobilize the foot. If this brings relief, the patient can have shoe inserts or modifications, orthotics or an ankle-foot orthosis (AFO) fitted.
  • Physiotherapy for achilles tendon stretching and tibialis posterior strengthening along with nonsteroidal anti-inflammatories can also help.
  • Up to 4 months of nonoperative treatment should be tried; if there is no improvement after this period, a tendon synovectomy or debridement may be indicated.

We are going to stop here to discuss some of these options. 

  • Walking boots can be helpful in some cases for a limited amount of time. Sometimes this is especially helpful for the patient who has a hard time “slowing things down” and do not allow their injury to heal.
  • Physical therapy, NSAIDs may not be effective for you. See below why these treatments were not as effective  as you may have hoped for.
  • Tendon synovectomy or Endoscopic Debridement is a surgery that may have been explained to you that will scrape away inflamed tissue off the tendon.

We are going to get back to these outlines but Stage 1 is the dividing line between conservative treatments and surgical intervention. If conservative care does not work, Stage II disease comes with more aggressive surgical recommendation.

The conservative care treatments for flat feet, why they did not work for you

Some people get benefit from conservative care treatment. Some people do not. If you are reading this article it is very likely that you did not get relief of your foot problems with these treatments. What is surprising to some patients we see is that they tell us that they tried many of these treatments on their own, and then, when the problems and symptoms they were having became more significant, they received the same treatment recommendations from their health care clinician. When they told the clinician that they had already tried these treatments, many simply received  stronger doses or recommendations to longer periods of rest and immobilization or “better” orthotics.

Let’s go through the roll call of conservative treatments.

  • RICE Therapy – Rest, Ice, compression, elevation. The idea is that problems of flat feet are made worse by inflammation in the arch and the posterior tibialis tendon.The recommendation to Rest, Ice, Compression, and Elevates seeks to tackle the inflammation problem without medication.
  • NSAIDs nonsteroidal anti-inflammatories – there is a good chance that if these medicines did not help, they are hurting you.  Why the NSAIDs did not help you and may have made your situation worse is covered in our article When NSAIDs make pain worse
  • Physical therapy and exercise. A September 2018 report in the British Medical Journal open sport and exercise medicine (2) from the University of Queensland concluded with this statement:
    • “Based on the limited available literature, it appears that local strengthening exercises provide some benefit in Posterior tibialis tendon dysfunction, and eccentric exercises (a downward motion with a weight load – such as a heel lift exercise – the motion of returning the heel to the floor would be considered eccentric exercises) may be superior for improving pain, disability and self-reported overall foot function than concentric exercises (in the same heel lift exercise – this would be the motion of standing on your toes and elevating you heel upwards) and foot orthoses and stretching alone.”
    • “No recommendations can currently be made regarding optimal exercise prescription based on published clinical trials.”
  • Arch support: The typical treatment for pain from fallen arches is an arch insert. While many people experience dramatic pain relief from this, others continue to suffer from chronic achy feet despite the arch support. The long-term problem with this approach is that it does not strengthen the weak arch ligaments that may be at the root of the problem.

As it became apparent that these treatments were failing, the patients then tell us that surgery was discussed on a more urgent basis. However, the surgery option for many of these people, presented a somewhat concerning option. It is a concerning option for surgeons as well, listen:

Surgical procedures are available; however, these require a lengthy recovery, and therefore patients should be advised accordingly”

Doctors at the University of Rochester wrote in the journal The Medical clinics of North America:(3) “The mainstay of nonoperative treatment (for adult acquired flatfoot deformity) is nonsteroidal anti-inflammatory drugs, weight loss, and orthotic insoles or brace use. The goals of therapy are to provide relief of symptoms and prevent progression of the deformity. If nonoperative management fails, a variety of surgical procedures are available; however, these require a lengthy recovery, and therefore patients should be advised accordingly.”

Long recovery time is not what an active person wants to hear.

Posterior tibialis tendon? Spring ligament? Plantar fascia? What is the cause of your flat feet? Is it really ankle problems? A study puts into question the primary importance of the tibialis posterior tendon.

In our opinion, nothing gives better evidence that your problems of flat feet can be coming from multi-factorial issues than the debate in the medical community as to what causes adult acquired flatfoot deformity and why certain conservative care treatments, like those mentioned above, are not helping.

A February 2019 study published in the Journal of biomechanics (4)  by medical university researchers in Spain gives the scenario that fallen arches and flat feet are the failure of many structures. The results of their research show that plantar fascia is the main tissue that prevents the arch elongation (flattening), while the spring ligament mainly reduces the foot pronation (turning inward, especially common in runner’s with flat feet). Long and short plantar ligaments play a secondary role in this process.

The stress increment on both plantar fascia and spring ligament when one of two fails suggests that these tissues complement each other. These findings support the theory that regards the tibialis posterior tendon as a secondary actor in the arch maintenance, compared with the plantar fascia and the spring ligament.

This 2019 study puts into question the primary importance of the tibialis posterior tendon.

Did flat feet cause posterior tibialis tendon dysfunction or did posterior tibialis tendon dysfunction cause flat feet?

In a 2004 study, the role of the tibialis posterior tendon was also questioned in a “what came first scenario.” Did flat feet cause posterior tibialis tendon dysfunction or did posterior tibialis tendon dysfunction  cause flat feet? This is what researchers at  Drexel University wrote about in the journal Clinical biomechanics (5).

  • Posterior tibialis tendon dysfunction, they suggest, causes an abnormal loading of the foot’s medial structures. This may be the reason that posterior tibialis tendon dysfunction leads to an acquired flatfoot deformity. Conversely, flatfoot deformity may be a predisposing factor in the onset of posterior tibialis tendon dysfunction.

foot ligamentsDid anyone discuss ligament damage with you? Introducing the ligament aspect the plantar calcaneonavicular ligament or “spring ligament.”

Although skeletal structure is important to arch support, without the ligaments, the arches would collapse. The plantar ligaments (ligaments on the bottom of the foot), which are stronger and larger than dorsal ligaments (ligaments on top of the foot), tie the inferior edges of the bones together. The most important ligament in the maintenance of the medial longitudinal arch is the plantar calcaneonavicular, or spring ligament.

The plantar calcaneonavicular ligament which passes from the lower surface of the calcaneus (heel bone) to the lower surface of the navicular bone (located just above the arch). This ligament resists the downward movement of the head of the talus, supporting the highest part of the arch, and is responsible for some of the elasticity of the arch. This ligament is also known as the spring ligament.

As we mentioned at the top of this article, problems of flat feet do not occur in isolation, they are typically the composite of many factors. Research is telling us this and our own clinical observation bear this out. Your problems with flat feet are more than a problem with the arch if your foot.

“Failure to recognize an isolated spring ligament injury as the primary cause of a flatfoot deformity could lead to inappropriate operative management.”

In the journal Foot and ankle international, (6) a study lead by Dr. J.D Orr at the William Beaumont Army Medical Center made this suggestion:

“Adult-acquired flatfoot deformity is usually secondary to tibialis posterior tendon failure but in rare cases may be secondary to isolated spring ligament injury without tibialis posterior tendon abnormality. This unique clinical entity should be considered in patients who present with flatfoot deformities.  . . Failure to recognize an isolated spring ligament injury as the primary cause of a flatfoot deformity could lead to inappropriate operative management.”

As we have discussed in this article, the challenges of surgical treatment of flat foot deformity are many, we have introduced you to surgical studies that outline these challenges, people do benefit from surgery, but there are challenges including the problem of “additional dissection” or additional cutting into the tissue when it may not be needed.

“It is beneficial to confirm the presence of ligament tears before surgical exploration to avoid unnecessary dissection”

At the Department of Orthopaedics and Traumatology, North District Hospital in China, doctors wrote in the journal Arthroscopy techniques (7) of the challenges of surgical repair:

“A tear of the spring ligament is frequently associated with posterior tibial tendon dysfunction. Repair of the damaged spring ligament is an important component of surgical reconstruction in the treatment of posterior tibial tendon dysfunction because it is a major anatomic contributor to the integrity of the medial longitudinal arch, particularly if the dynamic support of the posterior tibial tendon is compromised.

    • Extensive dissection is required for exposure and repair of the ligament because it is a deep-seated structure.
    • It is beneficial to confirm the presence of ligament tears before surgical exploration to avoid unnecessary dissection.
    • Preoperative magnetic resonance imaging and ultrasound studies have moderate sensitivity (not reliable) in the detection of these tears.”

Posterior tibial tendon insufficiency: which ligaments are involved?

The above is the title of a paper from doctors at the Hospital for Special Surgery published in the journal Foot and ankle international,(8) let’s go to the learning points of this study:

  • The challenges manifested in posterior tibial tendon insufficiency is not limited to the posterior tibial tendon.
  • The purpose of this observational study was to identify the pattern of ligament involvement in patients posterior tibial tendon insufficiency.
  • Ligament involvement is extensive in PTTI, and the spring ligament complex is the most frequently affected. Because ligament pathology in PTTI is nearly as common as posterior tibial tendinopathy, treatment should seek to protect or prevent progressive failure of these ligaments.
    • This includes the superomedial and inferomedial components of the spring ligament complex
    • talocalcaneal interosseous ligament, the primary connective link between the ankle and the heel.
    • long and short plantar ligaments, the ligaments of the arch.
    • plantar fascia,
    • deltoid ligament, provides stability to the ankle’s tibiotalar joint and to manage stress forces between tibia and tarsus (ankle)
    • plantar naviculocuneiform ligament, and
    • tarsometatarsal ligaments. (Both of these ligaments work withing the long bones of the toes).

It should be clear now that flat feet involve many ligaments. But how can you treat them all? Is it surgery?

The worse the condition, the more surgical options, but can non-surgical options still work?

We are going to return to the above research from the Journal of family medicine and primary care (1) to examine more surgical options and then to begin presenting our case for regenerative medicine techniques.

In the research we are citing, the doctors write about Stage II, III, and IV treatment challenges:

  • Nonoperative methods can still be tried at Stage II and include walking cast, CAM boots, or orthotics. These interventions often prove to be ineffective and surgical treatment is typically carried out in Stage II of the disease.
  • Surgical recommendation is made because the foot or bone deformity is still correctable and joint degeneration has not occurred, allowing for better joint alignment and possibly avoiding joint fusion.
  • A variety of surgical methods have been described, and these normally include bony procedures along with soft tissue reconstruction and tendon transfers.
    • Traditionally, this would consist of a combination of:
      • calcaneal osteotomy (heel bone shaving), posterior tibial tendon excision (removal or repair of parts of the tendon),
      • flexor digitorum longus transfer, in the journal Podiatry Today (9) March 2, 2017, Dr. Douglas H. Richie, Jr. wrote: “Despite the dismal results of transferring the flexor digitorum longus to the navicular in hopes of replacing the ruptured posterior tibial tendon, surgeons continued to embrace this concept as an adjunctive procedure to other approaches in adult-acquired flatfoot surgical correction, including a medializing calcaneal osteotomy and lateral column lengthening. . . It is quite remarkable that a procedure that by itself showed no benefit in adult-acquired flatfoot surgery continued to be a standard of operative care for over 40 years”
      • and achilles tendon lengthening (here doctors will try to stretch the Achilles tendon to take tension off the knee and arch).
  • When the disease progresses to Stage III and Stage IV there is ankle joint involvement.
    • Here doctors should work on pain management. Surgical intervention at these stages will involve multiple bony procedures such as osteotomies and arthrodesis. In Stage III typically a triple arthrodesis (fusion) of the calcaneocuboid, talonavicular and subtalar joints is undertaken, whereas in Stage IV an ankle joint fusion is performed, in addition to a triple arthrodesis.

How did we progress from shoe inserts to the triple fusion of the calcaneocuboid, talonavicular and subtalar joints PLUS ankle fusion?

It all started when you began noticing pain in the arch of your foot. You tried to manage this yourself, it got to be too much for you to manage on your own and you made a trip to the doctor. There the same treatments you were doing yourself, stretching the arch, taking anti-inflammatories, ICE, resting, taping, shoe inserts, were re-recommended to you. Maybe you were given strong medications, maybe you were sent to physical therapy, whatever happened, if you have made it to this point in our article, none of these treatments prevented the foot destruction you were suffering from.

Worse, the destruction of your foot is now extending from top to hip and possibly low back. When the ligaments that support the inside of the foot, especially the calcaneonavicular ligament, are damaged  the arch pain will increase. Eventually, the posterior tibialis tendon in the knee must help support the arch. This tendon eventually weakens, resulting in knee pain added to the original foot pain, as the arch continues to collapse.

Because the arch and the knee can no longer elevate the foot, the entire limb must be raised during a step, putting additional strain on the hip. The spring in the foot and the efficiency of the gait are drastically reduced due to the collapsed arch. This requires more energy from the foot, resulting in further deterioration of the medial arch. The more severe the collapse of the arch, the greater the likelihood of pain. The deterioration cycle will continue until something is done to support the arch. For many people, this is the triple fusion of the calcaneocuboid, talonavicular and subtalar joints PLUS ankle fusion.

Stopping the degenerative path of flat feet with Prolotherapy and PRP regenerative medicine injections.

We will begin this section with a short video and then we will get to the research.

Prolotherapy is the treatment that makes the most sense for a fallen arch due to weak ligaments. Prolotherapy injections into the fibro-osseous junctions of the plantar fascia and calcaneonavicular ligament, which supports the arch, will strengthen this area. If the condition is diagnosed early on, the ligaments can be strengthened to support the arch. If the process has gone on for years, an arch support may be needed in addition to Prolotherapy. But even in the latter case, Prolotherapy can eliminate the chronic arch pain.

Prolotherapy is the injection of a simple sugar, dextrose. The goal of the treatment is ligament repair. This is achieved by injecting the dextrose at the spot of ligament attachments that connect bones.

Treating the posterior tibialis tendon with Prolotherapy and PRP injections

The problems of treating tendon dysfunction with conservative care and surgical options, as we outlined above, is challenging. It is so challenging that surgeons published these observations in the  Journal of Experimental Orthopaedics.(10) December 2018.

  • Patients and health care providers have a choice to treat tendon problems with multiple non-invasive (non-surgery) and tendon-invasive (surgery) methods.
  • When traditional non-invasive treatments fail, the injections of platelet-rich plasma autologous blood (we will get to this below) or cortisone have become increasingly favored. However, there is little scientific evidence from human studies supporting injection treatment.
  • As the last resort, open or arthroscopic surgery to the tendon, or surgery to the tendon and surrounding soft tissue are employed even though these also show varying results.

Research: The great incidence of tendon injuries and a failure rate of up to 25% of the available conservative treatments has made alternative biological approaches (Platelet Rich Plasma) “most interesting.”

A fascinating part of this research is the investigators suggesting that: “The study of the microenvironment of tendinopathy is a key factor in improving tendon healing.” What is the microenvironment of tendinopathy? INFLAMMATION

Listen to what the researchers suggest, it will give you an understanding of how to heal by getting rid of anti-inflammatory medications.

  • “An alternative anti-inflammatory and immunomodulatory (suppressing the immune response, i.e., inflammation) approach that replaces the traditional anti-inflammatory modalities (i.e. NSAIDs) may provide another potential opportunity in the treatment of chronic tendinopathies.”

The research shows that even in cases of tendinosis, where it is thought that no inflammation is occurring, there is still inflammatory cellular activity. IN OTHER WORDS – your tendon is waiting for the inflammation to start up again and do its repair and there is a “skeleton crew,” of cellular communicators waiting for signals. Waiting for signals as we will see below is an important part of the tendons rebooting its healing cycle.

Fixing damage to the posterior tibialis tendon with pro-inflammatory treatments

Rebooting the inflammatory process means getting blood flow and healing factors back into the damaged area. This means a change of thinking from anti-inflammatory to PRO-inflammatory treatments.

The best way in our opinion to show you how pro-inflammatory treatments heal where anti-inflammatory treatments do not heal is in the research making a direct comparison.

A multi-national team of researchers including those from Rutgers University, Virginia College of Osteopathic Medicine, and the University Regensburg Medical Centre in Germany tested the effects of Prolotherapy on tenocytes repair (tendon cells). Published in the journal Clinical orthopaedics and related research(11) what the team was looking for was how did Prolotherapy injections change the immune system’s response to a difficult to teal tendon injury.

These are the highlights:

  • Prolotherapy injections changed the cellular metabolic activity to a healing, regenerative environment in the tendon cells.
  • Prolotherapy activated RNA expression. The healing phase of soft tissue injury starts spontaneously after the tendon injury. Healing occurs  in three phases: inflammation, proliferation and maturation. RNA expression is the communication changes in genes (remember the gene expression from above)  that coordinates the beginning and ending of these three cycles of healing and injury repair process.
  • Activated Protein secretion – the process of rebuilding. 
  • Cell migration. The ability of healing cells to get to the site of an injury, and the denial of damaging inflammatory factors from reaching the same site.

In our own published research, we reported in the Clinical medicine insights. Arthritis and musculoskeletal disorders, (12) we reported that the consensus is growing regarding the effectiveness of dextrose Prolotherapy as an alternative to surgery for patients with chronic tendinopathy who have persistent pain despite appropriate rehabilitative exercise.

Platelet Rich Plasma Therapy and Prolotherapy

Platelet Rich Plasma therapy (PRP) can be added to the traditional Prolotherapy solution to expedite the process, in specific cases.

  • PRP treatment re-introduces your own concentrated blood platelets into areas of chronic tendinopathy
  • Your blood platelets contain growth and healing factors. When concentrated through simple centrifuging, your blood plasma becomes “rich” in healing factors, thus the name Platelet RICH plasma.
  • The procedure and preparation of therapeutic doses of growth factors consist of an autologous blood collection (blood from the patient), plasma separation (blood is centrifuged), and application of the plasma rich in growth factors (injecting the plasma into the area.)
  • In our clinics, patients are generally seen every 4-6 weeks. Typically three to six visits are necessary per area.

Below is a pro-inflammatory treatment demonstration of Prolotherapy combined with PRP treatments. This simple treatment brings pro-inflammatory factors into the damaged area to stimulate healing.

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