Pes planus also known as flat foot is the loss of the medial longitudinal arch of the foot, heel valgus deformity, and medial talar prominence. In lay terms, it is a fallen arch of the foot that caused the whole foot to make contact with the surface the individual is standing on. The deformity is usually asymptomatic and resolves spontaneously in the first decade of life, or occasionally progresses into a painful rigid form which causes significant disability. All at birth has flat feet and noticeable foot arch are seen at around the age of 3years.
It is of two forms; flexible flat foot and rigid flat foot. When the arch of the foot is intact on heel elevation and non-bearing but disappears on full standing on the foot, it is termed flexible flat foot while rigid flat foot is when the arch is not present in both heel elevation and weight bearing.
Previous studies indicate the prevalence of flatfoot between < 1% and 28% at certain age groups. Pes planus is more prevalent in children and females are more predisposed to this condition than their male counterparts in adulthood. There are about 20-30% of children with some form of flat feet.
Pita-Fernandez et al reported a prevalence of 26.62% in random sample. Also, older individuals and high BMI are found to have a significant influence on having flat feet.
The etiology of flatfoot has several factors implicated. depending on etiology pes planus can be divided into types, namely congenital and acquired. These factors are:
- Talipes equinovarus deformity, ligamentous laxity, foot equinus deformity, tibial torsional deformity, presence of the accessory navicular bone, congenital vertical talus, and tarsal coalition.
- Diabetes and obesity are also probable factors related to pes planus.
- Foot and ankle injury such as rupture or dysfunction of the posterior tibial tendon
- Genetic malformation such as Down syndrome and Marfan syndrome
- Familial factors
- Arches weakness due to overuse and certain forms of foot condition or injuries
- Some medical conditions such as arthritis, spina bifida, cerebral palsy, Arthrogyroposis, and muscular dystrophy.
- Flat feet can also occur as a result of pregnancy.
- Iatrogenic factors such as posterior tibialis tendon (PTT) transfer.
The calcaneus, navicular, talus, first three cuneiforms, and the first three metatarsals make up the medial longitudinal arch. This arch is supported by posterior tibial tendon, plantar calcanea navicular ligament, deltoid ligament, plantar aponeurosis, and flexor hallucis longus and brevis muscles. Dysfunction or injury to any of these structures may cause acquired pes planus. Also, excessive tension in the triceps surae, obesity, Achilles tendon or calf muscle tightness, ligamentous laxity in the spring ligament, plantar fascia, or other supporting plantar ligaments may result in acquired flat foot.
Rigid pes planus is rare but usually starts from childhood; tarsal coalition, accessory navicular bone, congenital vertical talus, or other forms of congenital hindfoot pathology. are usually the underlying factors
The major symptom of flat feet is foot pain due to strained muscles and connecting tissues; Pain along the course of the posterior tibial tendon (PTT) and inability or pain upon attempts to perform a single-leg heel rise
Some individuals with flat feet have an inwards turned ankles with most of the weight bearing on the foot deviated medially.
Possible oedema at the medial side of the foot
Stiffness of one or both arches of the feet.
Contractures of feet and ankle muscles att the lateral compartment
Uneven distribution of body weight with resultant one-sided wear of shoes leading to further injuries.
Difficulty in walking
Co-morbidities include but not limited to neurological conditions such as cerebral palsy; genetics e.g downs syndrome, Marfan syndrome or Ehlers Danos; charcot joint; tibialis posterior dysfunction; Obesity; arthropathies; Shprintzen-Goldberg syndrome.
Surgery is required in rigid pes planus and in cases resistant to therapy to reduce symptoms. Most surgical methods aim at realigning foot shape and mechanics. These surgeries could be tendon transfers, realignment osteotomies, arthrodesis and where other surgeries fail, triple arthrodesis is performed
The aim of Physical therapy is to minimize pain, increase foot flexibility, strengthen weak muscles, train proprioception, and patient education and reassurance.
Pain management includes rest, activity modification, cryotherapy, massage, and nonsteroidal anti-inflammatory medication. Ultrasound and pulsed electrical stimulation can also be used for pain relief. Electric stimulation will aid blood circulation, promoting healing processes and diminishing discomfort and oedema.
Flexibility exercises are passive ROM exercise of the ankle and all foot joints; Stretching of gastrocnemius soleus complex and peroneus brevis muscles to facilitate varus and foot adduction; Heel-cord stretch for the Achilles tendon and calf muscles to relief tight heel cord.
Strengthening exercises are given to anterior and posterior tibialis muscles and the flexor hallucis longus, Intrinsic, interosseus plantaris muscles, and the abductor hallucis to prevent valgus and flattening of the anterior arch. Arch muscle strengthening exercise with theraband
Global activation of the muscles known to support the medial longitudinal arch and the varus with and without resistance.
Single leg weight bearing
For Proprioception, Toe and heel walking, Single leg weight bearing, and Descending an inclined surface are exercises that could be prescribed.
Also, Toe clawing of towel and pebbles, forefoot standing on a stair, toe extension and toe fanning/spreading, and heel walking are all good exercises to maintain viable foot arches.
Counselling on proper footwear, recommendation on motion control shoes, orthotics and braces are also needed. Foot orthotics such as shoe inserts are used to support the arch for foot pain secondary to pes planus alone or combination with leg, knee, and back pain.
Obese and overweight individuals should be counseled on weight loss through exercise and dieting; Possibly refer to a dietician for appropriate insight.
Other co-morbidities amenable to physiotherapy can also be treated following a proper examination and treatment plan.
Allen J, Solan S. Physiotherapy management of paediatric flat feet. Available from: https://www.peacocks.net/_filecache/316/436/892-physiotherapy-management-of-paediatric-flat-feet.pdf
Halimah bt. Hashim. Physiotherapy Management For Flat Foot (Pes Planus). Health Online Unit, Ministry of Health Malaysia, 2019. Available from: http://www.myhealth.gov.my/en/physiotherapy-management-for-flat-foot-pes-planus/Raj MA, Tafti D, Kiel J. Pes Planus (Flat Feet). StatPearl-NCBI Bookshelf, 2020. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430802/
- Troiano G, Nante N, Citarelli GL. Pes planus and pes cavus in Southern Italy: a 5 years study. Ann Ist Super Sanità. 2017;53(2):142-145. DOI: 10.4415/ANN_17_02_10
- Suciati T, Adnindya MA, Septadina IS, Pratiwi PP. Correlation between flat feet and body mass index in primary school students. IOP Conf. Series: Journal of Physics. 2019; 1246 : 012063 doi:10.1088/1742-6596/1246/1/012063
- Wilson DJ. Flexible vs Rigid Flat Foot, 2019. Available from: https://www.news-medical.net/health/Flexible-vs-Rigid-Flat-Foot.aspx (Accessed 29 June 2020)
- Pfeiffer M, Kotz R, Ledl T, Hauser G, Sluga M. Prevalence of flat foot in preschool-aged children. Pediatrics. 2006;118(2):634-9.
- Abdel-Fattah MM, Hassanin MM, Felembane FA, Nassaane MT. Flat foot among Saudi Arabian army recruits: prevalence and risk factors. Eastern Mediterranean Health Journal. 2006;12(1-2):211-7.
- Chen JP, Chung MJ, Wang MJ. Flatfoot prevalence and foot dimensions of 5- to 13-year-old children in Taiwan. Foot Ankle Intern. 2009;30(4):326-32
- Pita-Fernandez S, Gonzalez-Martin C, Alonso-Tajes F, Seoane-Pillado T, Pertega-Diaz S, Perez-Garcia S, et al. Flat foot in a random population and its impact on quality of life and functionality. J Clin Diagn Res. 2017;11:LC22–27.
- Raj MA, Tafti D, Kiel J. Pes Planus (Flat Feet). StatPearl-NCBI Bookshelf, 2020. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430802/ (Accessed 29 June 2020)
- Cheong IY, Kang HJ, Ko H, Sung J, Song Y-M, Hwang JH. Genetic Influence on Accessory Navicular Bone in the Foot: A Korean Twin and Family Study. Twin Research and Human Genetics. [Online] Cambridge University Press; 2017;20(3): 236–241. doi:10.1017/thg.2017.21
- Cleveland Clinic. 2019. Available from:https://my.clevelandclinic.org/health/diseases/15961-adult-acquired-flatfoot#:~:text=In%20people%20with%20diabetes%2C%20a,notice%20as%20their%20foot%20collapses. (Accessed 29 June 2020)
- Harrison W. Pes planus and paediatric obesity. Physiospot, 2015. Available from: https://www.physiospot.com/research/pes-planus-and-paediatric-obesity/ (Accessed 30 June 2020)
- Buerk AA, Albert MC. Advances in pediatric foot and ankle treatment. Curr Opin Orthop. 2001;12:437-42.
- Wearing SC, Hennig EM, Byrne NM, Steele JR, Hills AP. Musculoskeletal disorders associated with obesity: a biomechanical perspective. Obesity reviews: an official journal of the International Association for the Study of Obesity. 2006;7(3):239-50.
- Mosca VS. Flexible flatfoot in children and adolescents. J Child Orthop. 2010;4(2):107–121
- Berlet GC. Pes Planus (Flatfoot). Medscape, 2019. Available from: https://emedicine.medscape.com/article/1236652-overview#a8 (accessed 29 June 2020)
- Indy Podiatry. Common foot and ankle problems during pregnancy, 2019. Available from: https://indypodiatry.com/your-feet-during-pregnancy/#:~:text=Over%2Dpronation%2C%20or%20flat%20feet,feet)%20leading%20to%20significant%20pain. (accessed 29 June 2020)
- Conder R, Zamani R, Akrami M. The Biomechanics of Pregnancy: A Systematic Review. J. Funct. Morphol. Kinesiol. 2019; 4(72):1-17 doi:10.3390/jfmk4040072
- Pecheva M, Devany A, Nourallah B, Cutts S, Pasapula C. Long-term follow-up of patients undergoing tibialis posterior transfer: Is acquired pes planus a complication? Foot (Edinb). 2018; 34:83-89.
- Mount Sinai Health Systems. What causes flat foot? Available from: http://www.youtube.com/watch?v=GPS10HfgYDY [last accessed 29/6/2020]
- East Coast Podiatry. Flat Feet (Pes Planus) - Georgina Tay, Singapore Podiatrist . Available from: http://www.youtube.com/watch?v=9tlzxA8o0w0 [last accessed 29/6/2020]
- Lowth M. Pes Planus (Flat feet). Patient, 2016. Available from: https://patient.info/doctor/pes-planus-flat-feet (Accessed 30 June 2020)
- Yadav S, Rawal G. Shprintzen-Goldberg syndrome: A rare disorder. Pan African Medical Journal. 2016; 23:227 doi:10.11604/pamj.2016.23.227.7482
- Henry JK, Shakked R, Ellis SJ. Adult-Acquired Flatfoot Deformity. Foot & Ankle Orthopaedics. 2019; 4(1):1-17 DOI: 10.1177/2473011418820847
- Carr JB, Yang S, Lather LA. Pediatric Pes Planus: A State-of-the-Art Review. Pediatrics. 2016; 137 (3): e20151230. DOI: https://doi.org/10.1542/peds.2015-1230
- Allen J, Solan S. Physiotherapy management of paediatric flat feet. Available from: https://www.peacocks.net/_filecache/316/436/892-physiotherapy-management-of-paediatric-flat-feet.pdf (Accessed 30 June 2020)
- Halimah bt. Hashim. Physiotherapy Management For Flat Foot (Pes Planus). Health Online Unit, Ministry of Health Malaysia, 2019.Available from: http://www.myhealth.gov.my/en/physiotherapy-management-for-flat-foot-pes-planus/ [Accessed 30 June 2020]
- Blitz NM, Stabile RJ, Giorgini RJ, DiDomenico LA. Flexible pediatric and adolescent pes planovalgus: conservative and surgical treatment options. Clin Podiatr Med Surg. 2010;27(1):59–77
- AskDoctorJo. 7 Best Flat Feet Treatments - Ask Doctor Jo. Available from: http://www.youtube.com/watch?v=y6b4GeYY9sg [last accessed 30/6/2020]