Adult Acquired Flatfoot
1. Introduction
Posterior tibialis tendon dysfunction is the most common cause of adult acquired flatfoot and is described in 4 stages (4).
- Stage 1 – the tendon is intact and, to some degree, functioning (it can be inflamed).
- Stage 2 – the tendon has become dysfunctional and the foot has developed an acquired flatfoot deformity, but the deformity is passively correctable.
- Stage 3 – the foot deformity has become fixed and degenerative changes are seen in the subtalar joint.
- Stage 4 – occurs when degenerative changes are also present in the ankle joint as well as the subtalar joint.
The main function of the posterior tibialis muscle is to provide dynamic stabilisation of the inner arch of the foot. This initial dysfunction can lead to a cascade of worsening pathological events, therefore early diagnosis may be important in delaying or preventing worsening symptoms associated with this condition.
Frequently Asked Questions
- Adult acquired flat foot is a condition where the main arch of the foot loses its height giving the appearance that the foot sits flat on the floor.
- Posterior tibial tendon dysfunction is the most common cause of adult-acquired flatfoot.
- It typically occurs in middle-aged women, particularly those with an elevated BMI, and is reported to occur in 3%-10% of this group (3).
- No
- Symptomatic posterior tibial tendon dysfunction can be successfully treated non-surgically with physiotherapy (4).
- More common in women over 40.
- Typically, those who have a high body mass index.
- People who experience the condition have other likely medical conditions such as high blood pressure, diabetes and previous surgery in the area (3).
- Flattened foot arch.
- Often the pain will start along the instep of the foot, with pain developing behind the inner ankle bone and up the inner aspect of the leg.
- A defining symptom is often an inability, or difficulty, to heel rise (go up on tiptoes).
- If symptomatic, adult acquired flatfoot can generally be managed conservatively with specific advice and a personalised strengthening programme provided by a physiotherapist.
- Lifestyle changes, such as losing weight.
- Activity modification.
- Exercise and physical activity to improve strength, health and fitness.
- Rehabilitation time will vary between individuals and is dependent on the stage of the condition.
- Generally, allowing for anything up to 4 months of rehabilitation would be recommended (2).
We recommend consulting a musculoskeletal physiotherapist to ensure exercises are best suited to your recovery. If you are carrying out an exercise regime without consulting a healthcare professional, you do so at your own risk.
2. Signs and Symptoms
Often the pain will start along your instep of the foot with pain developing behind the inner ankle bone and up the inner aspect of your leg. You may have difficulty walking, with a generalised ache which may exacerbate throughout the day. A defining symptom is often an inability or difficulty to heel rise (go up on tiptoes) because your tibialis posterior tendon has a reduced capacity to perform this effectively. As symptoms and the condition deteriorate, inner ankle pain may be followed by pain on the outside of the ankle also, resulting from biomechanical changes.
3. Causes
The dysfunction of the posterior tibial tendon is a multifactorial process and can be difficult to attribute to a single cause. In many patients, there is a pre-existing flatfoot and many patients are also overweight, leading to increased stress on the tendon (1).
Episodes of previous trauma, corticosteroid injections, arthritis, neuromuscular conditions and diabetes all increase the risk of the development of the condition (1).
4. Risk Factors
This is not an exhaustive list. These factors could increase the likelihood of someone developing adult acquired flat foot. It does not mean everyone with these risk factors will develop symptoms.
- Increased weight
- Previous injury to the foot/ankle
- Genetics
- Lack of strength in the intrinsic (small) muscles of the feet
5. Prevalence
Adult acquired flatfoot is more common in middle-aged adults, particularly females with an elevated BMI, and has a reported prevalence in the UK between 3%-10% (3).
6. Assessment & Diagnosis
Your physiotherapist will ask for a history of your symptoms, proceeded by carrying out a clinical examination so that a precise and timely diagnosis can be given to ensure the most effective treatment can be put in place immediately. Your physiotherapist will work closely with you to set individualised treatment goals and will regularly reassess you to measure your progress and make any necessary modifications in your treatment.
7. Self-Management
Upon receiving your diagnosis, your clinician will educate you on the condition so that you can understand how you can help manage your symptoms. The physiotherapist will suggest activity modification strategies that will allow you to remain functional without causing symptom exacerbation. Additionally, your physiotherapist can suggest ways to help reduce pain and recommendations on pharmaceuticals that can make you more comfortable, collaborating with your GP where needed.
8. Rehabilitation
Adult acquired flatfoot can generally be managed conservatively with specific advice and a personalised and progressive strengthening programme that your specialist physiotherapist can design to increase the strength of the soft tissues involved (2). Your physiotherapist will understand the structures that need strengthening and will tailor your exercises towards the activity-related and functional goals that will be established. You will regularly be reassessed to measure progress and we provide ongoing support and advice so that you can effectively and autonomously manage your symptoms.
9. Adult Acquired Flatfoot
Rehabilitation Plans
Our team of expert musculoskeletal physiotherapist have created rehabilitation plans to enable people to manage their condition. If you have any questions or concerns about a condition, we recommend you book an consultation with one of our clinicians.
What Is the Pain Scale?
The pain scale or what some physios would call the Visual Analogue Scale (VAS), is a scale that is used to try and understand the level of pain that someone is in. The scale is intended as something that you would rate yourself on a scale of 0-10 with 0 = no pain, 10 = worst pain imaginable. You can learn more about what is pain and the pain scale here.
This programme focuses on maintaining and restoring ROM (range of motion) with beginner strengthening exercises to the ankle and foot complex. All exercises should be kept to a tolerable level of pain. This should not exceed any more than 4/10 on your perceived pain scale.
- 0
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 910
This is the next progression. More focus is given to progressive loading of the foot and ankle to rebuild strength, stability, and proprioception (proprioception refers to the body’s ability to perceive its position in space). This should not exceed any more than 4/10 on your perceived pain scale.
- 0
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 910
10. Return to Sport / Normal life
For patients wanting to achieve a high level of function or return to sport, we would encourage a consultation with a physiotherapist as you will likely require further progression beyond the advanced rehabilitation stage. Before returning to your sport, a rehabilitation programme should incorporate plyometric-based exercises; this might include things like jumping and running exercises (5, 7).
As part of a comprehensive treatment approach, your musculoskeletal physiotherapist may also use a variety of other pain-relieving treatments to support symptom relief and recovery. Whilst recovering, you might benefit from a further assessment to ensure you are making progress and to establish an appropriate progression of treatment. Ongoing support and advice will allow you to self-manage and prevent future reoccurrence.
11. Other Treatment Options
The most common intervention with this condition is the use of orthotics. These can be off the shelf insoles that are used to create support for the arch of the foot or custom insoles that are made specifically for your feet. It is advised to use these in conjunction with a tailored exercise programme.
References
- Arain A, Harrington MC, Rosenbaum AJ. Adult Acquired Flatfoot. [Updated 2020 Aug 10]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK542178/
- Alvarez, R. G., Marini, A., Schmitt, C., & Saltzman, C. L. (2006). Stage I and II posterior tibial tendon dysfunction treated by a structured nonoperative management protocol: an orthosis and exercise programme. Foot & ankle international, 27(1), 2-8.
- Bubra PS, Keighley G, Rateesh S, Carmody D. Posterior tibial tendon dysfunction: an overlooked cause of foot deformity. J Family Med Prim Care. 2015;4(1):26-29. doi:10.4103/2249-4863.152245
- Kohls-Gatzoulis J, Woods B, Angel JC, Singh D. The prevalence of symptomatic posterior tibialis tendon dysfunction in women over the age of 40 in England. Foot Ankle Surg. 2009;15(2):75-81. doi: 10.1016/j.fas.2008.08.003. Epub 2008 Oct 1. PMID: 19410173.
- Nielsen MD, Dodson EE, Shadrick DL, Catanzariti AR, Mendicino RW, Malay DS. Nonoperative care for the treatment of adult-acquired flatfoot deformity. J Foot Ankle Surg. 2011 May-Jun;50(3):311-4. doi: 10.1053/j.jfas.2011.02.002. Epub 2011 Mar 31. PMID: 21458301.
- Vulcano, E., Deland, J. T., & Ellis, S. J. (2013). Approach and treatment of the adult acquired flatfoot deformity. Current reviews in musculoskeletal medicine, 6(4), 294-303.
Other Conditions in
Feet, Long Term Conditions
Plantar Fasciitis
Pain under the foot caused by irritation of the plantar fascia (a strong band of tissue that runs along the sole of the foot).
Complex Regional Pain Syndrome
A rare condition where a person experiences persistent, severe and debilitating pain, often with a complex cause.
Achilles Tendinopathy
Pain, swelling and stiffness of the achilles tendon that joins the heel bone to the calf muscles.