Pes Planus/Adult Acquired Flatfoot Deformity

Disease/Disorder

Definition

Adult acquired flatfoot deformity (AAFD), also referred to as progressive collapsing foot deformity (PCFD), is defined by the collapse of the medial longitudinal arch with progressive deformity of the foot and ankle.^1,2 It combines multiple static and dynamic deformities, including flattening of the medial arch, hindfoot valgus with eversion of calcaneus, and abduction of forefoot relative to the hindfoot.³ AAFD may affect one or both feet, and is considered pathological when symptoms such as pain, malalignment, or functional limitations are present.³ In long-standing cases, ankle involvement with valgus talar tilt or deltoid ligament failure may also develop.^2,4

Etiology

Pes planus (also known as “flat feet”) may be congenital or acquired. Congenital causes include tarsal coalition, an abnormal connection between tarsal bones due to incomplete differentiation of bones, which may present as medial foot pain during late childhood or adolescent with increased activity. Infants and young children are prone to have absent arches from ligamentous laxity and lack of neuromuscular control. Most children develop normal arches by age 5 to 6, however a small percentage fail to develop a normal arch by adulthood.⁵

Acquired flatfoot deformity is most commonly secondary to posterior tibial tendon dysfunction (PTT). The PTT is particularly vulnerable to damage or rupture at the region of hypovascularity 1.0-1.5 cm distal to the medial malleolus. Attenuation of the spring and deltoid ligaments commonly coexists and contributes to collapse of the medial arch

Injuries that can lead to pes planus include fractures of the navicular, first metatarsal, calcaneal bones, and/or trauma to the Lisfranc joint, plantar fascia, and deltoid/spring ligament. Patients with neuropathies, particularly diabetics with Charcot neuroarthropathy, may develop severe midfoot collapse and rocker-bottom deformity over time.⁵Epidemiology and risk factors for prevention

Adult acquired flatfoot is a debilitating condition that affects up to 5 million people within the US.⁴ It is most common in females over the age of 40, peaking at 55 years of age, with higher rates in overweight and obese population.^2,5,6

Risk factors of acquired flat foot⁶

• Diabetes
• Obesity
• History of trauma
• Degeneration of bones and joints
• Seronegative inflammatory disorders
• Increased age
• Corticosteroid use
• Hypertension
• Generalized ligamentous laxity

Any injury to the structures mentioned above under the ‘Etiology’ subtopic maintaining the arch may lead to pes planus.

Patho-anatomy and physiology

One transverse and two longitudinal arches are formed by the aligned wedge-shaped tarsal and metatarsal bones, and their corresponding ligaments. In addition to these static structures, musculo-tendinous structures (tibialis posterior, peroneal, and tibialis anterior tendons) dynamically stabilize the arch. The design of the arches can be understood by picturing the foot as a twisted osteoligamentous plate (Figure 1). The anterior edge of the plate (formed by the metatarsal heads) is horizontal and in full contact with the ground and the posterior edge of the plate (the posterior calcaneus) is vertical. The resulting twist forms one transverse and two longitudinal arches (Figure 2). The medial longitudinal arch (between the calcaneus and first metatarsal) is higher and more flexible compared to the lateral longitudinal arch (between the calcaneus and lateral metatarsal). The actual mechanism of twisting and untwisting is accomplished through motion at the talocalcaneonavicular, transverse tarsal, and tarsometatarsal joints that link the bones of the plantar arches.⁶

PTT inserts to 9 bones including navicular tuberosity, 3 cuneiforms, 2nd – 4th metatarsal heads, the cuboid bone, and sustentaculum tali of calcaneus.^6,5 The PTT adducts and supinates the forefoot secondarily inverting the subtalar joint. When the hindfoot is everted the transverse tarsal joint (talonavicular, calcaneocuboid) is unlocked which allows the foot to remain supple. When the hindfoot is inverted, the transverse tarsal joint locks and the foot becomes rigid. Figure 1: Twisted osteoligamentous plate of the foot, resulting in longitudinal and transverse arches

Figure 2: Depiction of the Medial longitudinal, lateral longitudinal, and transverse arches of the foot.

Immediately after heel strike, the subtalar joint is inverted and the foot is supple.⁴ The plate will untwist, flattening the arches slightly. As the foot unloads weight, the resilient arches return to their original shape.⁶ The subtalar joint becomes progressively inverted which is initiated by the PTT adducting the transverse tarsal joint. The divergence at the transverse tarsal joint (calcaneocuboidal and talonavicular joints) allows the subtalar complex to become rigid. This enables the gastrocnemius-soleus complex to provide a plantar flexion force against a rigid lever to allow forward progression during the push-off phase of the gait cycle. Therefore, the PTT is critical in inverting the hindfoot and locking the transverse tarsal joint for normal gait and ambulation.⁴ The PTT also works eccentrically throughout the loading response until midstance where the foot is pronated providing controlled lengthening contraction.

The integrity of the talonavicular joint is maintained by the calcaneonavicular ligament (spring ligament) and portions of the superficial deltoid ligament.⁴ The PTT protects these structures and also plays an essential role in the elastic support of the joint complex.⁵ The spring ligament (also known as the plantar calcaneonavicular ligament) is considered a primary static stabilizer of the medial arch, second in importance only to the PTT.² The PTT dysfunction results in attenuation of these important ligaments and leads to diminished hindfoot inversion and the peroneus brevis acting unopposed with a dynamic abduction-eversion force.

The common point in all deformities causing adult flatfoot is failure of foot-locking during gait.⁵ Individuals with pes planus tend to develop shortening of the gastrocnemius muscle and achilles tendon due to a pronated calcaneus relative to the tibia. This relative equinus state –a lack of full passive ankle dorsiflexion – drives the subtalar and midtarsal joint into further pronation. Restoring ankle dorsiflexion or accommodating it is a key part of managing symptomatic pes planus.

Disease progression including natural history, disease phases or stages, disease trajectory (clinical features and presentation over time):

Posterior Tibial Tendon Insufficiency Related Pes Planus

Table 1. Myerson Modification of Johnson and Strom Classification of Adult-Acquired Flatfoot Deformity

Specific secondary or associated conditions and complications:

• Midfoot arthritis (strain of medial midfoot, compression of lateral midfoot)
• Attenuation of spring and deltoid ligaments
• 1^st MTPJ Valgus deformity (bunion)
• Medial ankle pain
• Sinus tarsi pain
• Shortening of gastrocnemius
• Knee valgus deformity
• Tibial/femoral internal rotation
• Calcaneocuboid impingement

Essentials of Assessment

History

Thorough medical history (including systemic comorbidities), developmental history, surgical history, family history of pes planus, activity level, and prior foot/ankle trauma should be documented. Clinical assessment is important to determine the severity of the deformity and its reducibility. Majority of patients with PTT dysfunction describe a gradual onset of unilateral medial ankle and foot pain and deformity without clear history of trauma.⁵ Upon palpation, tenderness is along the PTT between medial malleolus and navicular bone.⁴ Pain on the plantar and deep region may suggest spring ligament lesion.⁸ In the late stage, patients may develop lateral hindfoot pain including below the tip of the fibula due to bone impingement within the sinus tarsi or the calcaneofibular region. In cases of severe forefoot abduction, pain may arise from calcaneocuboid impingement.⁵

Physical examination

Inspection

Inspect for valgus deformity of the heel (Figure 3b), collapse of the medial longitudinal arch, and forefoot abduction. The ‘Too many toes sign’ (more than 1 or 2 toes visible on lateral border of foot when  viewed from behind) (Figure 3d) indicates forefoot abduction, though not the entire pronation deformity of the foot.⁸ Clinicians should ensure the patellae face forward to avoid false positive results.⁸ Assess whether the pes planus is rigid or flexible by inspection of the medial longitudinal arch while weight-bearing and non weight-bearing. Footwear should be examined for wear patterns, as pes planus often has posteromedial heel wear.

Figure 3

3a: Location of maximum tenderness on PTT dysfunction

3b. Everted calcaneus on the left side

3c. Bilateral pes planus with forefoot abduction in a patient with PTT dysfunction

3d. Too many toes sign in a patient with adult acquired flatfoot

Range of motion

The mobility of the ankle, subtalar joint, and transverse tarsal joint should be assessed. It is also important to determine whether the flatfoot deformities (tibiotalar and subtalar joints and Chopart and Lisfranc joint lines) are reducible for orthotic management. Stage III deformities typically can no longer be passively corrected, requiring accommodative management.⁸

Evaluation of ankle flexibility and shortening of the gastrocnemius and Achilles tendons should be done since ankle equinus drives the subtalar and midtarsal joints into pronation. Normally, 20 degrees of dorsiflexion and 50 degrees of plantar flexion occur at the ankle joint. Care should be taken to check the dorsiflexion of ankle with foot in slight inversion if the subtalar joint is supple. This reveals the true motion at the ankle joint.

The motion at the subtalar joint is evaluated by stressing the calcaneus into varus (normal <30 degrees) inversion and valgus (normal <10 degrees) while grasping the calcaneus with one hand and locking the ankle joint with the other. The motion of the transverse tarsal joint should be evaluated next for abduction and adduction. With the heel placed into inversion, there is a moderate degree of rigidity to the transverse tarsal joints. Degenerative process in these joints may restrict the motion.⁴

Palpation

Evaluate for tenderness and swelling along course of PTT (seen during stage I PTT dysfunction (Figure 3a)). Tenderness in sub-fibular region may indicate calcaneofibular impingement. Test the integrity of the PTT by asking the patient to invert and plantarflex the foot against resistance while the examiner applies an eversion force.⁸

Functional assessment

Special testing

To evaluate the strength and integrity of the PTT, heel rise tests are performed with the patient standing roughly 2 feet away from the wall with the hands placed against the wall. The patient is asked to rise up on the balls of the feet with the knees extended while calcaneal motion is observed. Failure of inversion of the heel suggests PTT dysfunction. A single heel rise test is then performed. Inability to raise the heel and to maintain heel inversion and elevation is strongly indicative of PTT dysfunction.

Gait evaluation

The patient’s gait is evaluated while walking down a hallway. Any antalgic gait or limp on the affected limb with external rotation should be noted, as it decreases the stress on the subtalar-ankle joint complex.⁴ Flexible pes planus may be observed if there is a loss of the medial longitudinal arch on weight-bearing.

Laboratory studies

There are no specific laboratory studies indicated for pes planus.

Imaging

Radiographic evaluation

Weight-bearing radiographs of the foot and ankle remain the gold standard for the diagnosis of adult-acquired flatfoot deformity. Anteroposterior, lateral and hindfoot views should be obtained.

• Anteroposterior (AP) view: Forefoot abduction and talar head uncoverage may be demonstrated. Different parameters have been described to assess talar head uncoverage, including the anterior talus-first metatarsal angle (normal, 0°; flatfoot: mild >4°,moderate >15°, severe >30°)talonavicular coverage angle (normal<7°, flatfoot >7°), talonavicular uncoverage percent (normal, 10% to 30%; flatfoot >30%), and lateral incongruency angle (normal, 5° = –26°; flatfoot >26°)
• Lateral radiographs view: Naviculocuneiform and first tarsometatarsal joint collapse should be investigated. The lateral talar-first metatarsal angle (Meary angle) is  the angle between the longitudinal axes of the talus and first metatarsal (normal, 0° + 10°; flatfoot often >20°, apex directed plantarly). Calcaneal pitch is defined as the angle between the line parallel to the ground and the line along the inferior inclination axis of the calcaneus (normal, 20°–30°; flatfoot <20°)
• Hindfoot alignment view: Hindfoot valgus can be evaluated. Hindfoot moment arm can be measured by the shortest distance between mid-tibial axis and most inferior portion of the calcaneus gus (normal, -3 mm to +10 [varus]; flatfoot, >+10 mm [valgus]). Hindfoot alignment angle is formed by intersection of the longitudinal axis of the tibial shaft and axis of calcaneal tuberosity (normal, 5.6 + 5.4°; flatfoot, 22.5 + 4.9°).²

All radiographs should be carefully examined to identify arthritic changes that could substantially affect treatment choice (i.e., joint fusion vs soft tissue procedures and osteotomies).⁶ Additionally, radiographs can assist in the diagnosis of Charcot foot.

Supplemental assessment tools

MRI is not routinely needed but is highly accurate for PTT tears and is particularly helpful in evaluating spring ligament integrity and medial peritalar instability.⁵ Ultrasound offers a cost-effective alternative, with diagnostic accuracy for PTT pathology comparable to MRI in most cases. Weight bearing CT is increasingly used in complex or surgical cases, providing 3D evaluation of deformity, joint subluxation, and impingement.²

Early predictions of outcomes

Johnson and Strom described 4 stages of PTT dysfunction.⁹ These stages are used to dictate treatment.

• Stage 1: Characterized by peritendinitis and tendon degeneration, but the tendon length remains normal. This stage presents clinically as pain and swelling along the PTT sheath.
• Stage 2: the PTT elongates, and a flexible flat foot deformity develops. Although deformed on weight bearing, the hindfoot and midfoot deformities are passively correctable to neutral position.
• Stage 3: Over time, the hindfoot becomes rigid in a valgus position, and the patient develops a rigid flatfoot deformity.
• Stage 4: The deltoid ligament becomes incompetent and the talus tilts into valgus within the ankle mortise.

Stage and flexibility at presentation remains strongest predictor of prognosis.¹⁰  

Environmental

Running or walking on uneven ground (e.g. slanted pavement) may exacerbate pain and discomfort. Footwear with an anti-pronation or motion-control features may help the pain and position of the foot. In the athletic population, high impact sports can lead to PTT dysfunction and pes planus.⁵

Social role and social support system

Occupation or lifestyle that involve prolonged standing or heavy weight bearing can accelerate progression of deformity. Appropriate footwear with pronation support with orthoses can be beneficial to patients. ⁵

Professional issues

Vocations requiring dress shoes may be a problem for these individuals, as people with pes planus tend to have wide feet and may need special footwear. Additionally, symptomatic pes planus may limit participation in physical jobs including military service. Veterans with symptomatic pes planus linked to service may obtain a VA disability rating of 0-50%.

Rehabilitation Management and Treatments

Available or current treatment guidelines

Initial treatment for all stages of PTT dysfunction includes various non-operative treatments including activity modification and nonsteroidal anti-inflammatory drugs (NSAIDs).⁸

Structured exercise therapy including posterior tibial strengthening combined with iliopsoas stretching and towel curl exercises produce the greatest improvement in navicular drop. Hip focused neuromuscular training and combined intrinsic foot plus gluteal strengthening were found to be effective for improving arch posture and lower limb alignment. For foot function, orthosis combined with stretching and eccentric PTT strengthening was found to be most effective. Exercise protocol at least 6-12 weeks, performed three or more times a week were associated with best outcomes. These findings reinforce benefits of combining orthotic management with progressive strengthening of both foot/ankle and hip/pelvic musculature.¹¹

If pain persists despite non-operative interventions for 3 to 4 months, then surgical intervention may be considered. Surgery should address the components of the deformity and its reducibility at 3 levels: the talonavicular, tibiotarsal, and midfoot joints.⁵

At different disease stages

Non-operative treatment of PTT Dysfunction

• Stage I: It may be treated with immobilization in a short-leg cast or walking boot for 4 to 6 weeks to allow for healing of the PTT. The patient may participate in physical therapy for eccentric strengthening of the PTT after cast immobilization. Anti-inflammatory medications may assist in reducing inflammation.⁹ If immobilization and physical therapy are successful, transitioning into custom-molded orthotics or ankle foot orthosis (AFO) is beneficial to maintain relief. Emphasis on medial forefoot posting is critical. University of California Biomechanics Laboratory (UCBL) orthoses are a form of a custom insert with a lace-up component that can help maintain midfoot height.¹² Ankle stirrup braces may also be used in stage 1 PTT dysfunction.⁹
• Stage IIa: It is treated with orthoses as recommended in stage 1. Stage IIa may involve some deformity or impending deformity, thus necessitating support of the longitudinal arch and heel. An orthotic device with a deep heel cup is usually sufficient.
• Stage IIb: Patients may require a University of California Biomechanics Laboratory (UCBL) device or AFO for reducing forefoot abduction.⁴ Modifications in footwear, such as an extended medial counter or medial heel wedge, may be helpful. In the acutely painful foot, immobilization may be warranted.⁴
• Stage III: Patients may require some type of custom AFO or supramalleolar (SMO) brace. The AFO should be articulated to permit ankle joint range of motion. Unfortunately, once the deformity is fixed, the patient may have difficulty tolerating corrective types of AFOs. Partial correction with a heel lift to accommodate the equinus of ankle can be attempted.
• Stage IV: Non-operable stage IV PTT dysfunction is usually treated with footwear with medial posting and a buttress to accommodate the deformity.

Surgical treatment of PTT Dysfunction

• Stage I: If non-operative treatment fails, a tenosynovectomy may be considered. Tenosynovial tissue should be resected and any tears should be debrided and repaired.
• Stage IIa: reconstructive surgery is often indicated, including PTT debridement and medial displacement calcaneal osteotomy (MDCO).  Other procedures to be taken into account would include lateral column lengthening and flexor digitorum tendon (FDL) transfer.¹⁰
• Stage IIb: More extensive correction with lateral column lengthening or isolated subtalar joint arthrodesis may be preferred at this stage. Subtalar arthroereisis (a reversible minimally invasive procedure to control hindfoot eversion) is also considered but remains controversial.¹³
• Stage III: This results from hindfoot valgus deformity with or without arthrodesis. A medial double arthrodesis or triple arthrodesis (subtalar, calcaneocuboid, and talonavicular arthrodesis) is indicated with or without deltoid ligament repair as it involves hindfoot arthritic changes. Gastrocnemius recession or Achilles lengthening is often performed to address equinus contracture however also remains debated.^4,9,10
• Stage IV: As ankle joint (tibiotalar) changes are noted, a triple arthrodesis in combination with deltoid ligament repair and a medializing calcaneal osteotomy may be considered in patients with valgus deformity of the ankle without degenerative joint disease. In severe cases, a pan-talar fusion (tibiotalar, subtalar, talonavicular, and calcaneocuboid joints) may be necessary.^4,9

Coordination of care

Parallel practice: Patients may be rehabilitating but still working or competing.
Coordinated: Employers, coaches, and family may need to be involved to promote a successful outcome.
Multidisciplinary: Athletic trainers, physical therapists, and orthotists may be involved.
Interdisciplinary: Foot-ankle trained orthopedic surgeons or podiatrists can be consulted in refractory cases.

Patient & family education

Educate on the importance of gastrocnemius stretching, appropriate training volume and intensity, appropriate shoe wear. Patients should be counseled on the role of orthoses, emphasizing gradual wear time to improve tolerance.¹⁴ Different athletic shoes should be worn every 6 months and can be rotated for longer wear.

Measurement of treatment outcomes including those that are impairment-based, activity participation-based and environmentally-based

The Foot Function Index (FFI) is a 0-10 scale of pain and foot function over time in standing, walking, etc. The Foot Health Status Questionnaire (FHSQ) is a 42-item questionnaire assessing quality of foot health. The Foot and Ankle Ability Measure (FAAM) is an activities-of-daily-living scale of foot health.) Self-Reported Foot and Ankle Score (SEFAS) has been widely used in registry studies for hindfoot disorders.¹⁰ These measures can be used to assess pain severity and to monitor response to treatment.

Translation into practice:  practice “pearls”/performance improvement in practice (PIPs)/changes in clinical practice behaviors and skills

Assessing the pain at initial presentation and measuring the improvement in pain score with footwear and orthosis will be needed. The minimal clinical meaningful difference for pain scale (0-10) is 2. Orthotic interventions often do not correct deformities; however, they improve comfort and function while targeted exercises enhance long term outcomes.¹⁰

Cutting Edge/Emerging and Unique Concepts and Practice

Key point in orthoses

UCBL, SMO, and short rear-entry AFO are designed to align the subtalar complex by directly controlling calcaneal eversion and forefoot abduction, which also allows for healing of the PTT if involved. The lateral border of the UCBL or SMO is formed up to the fifth metatarsal shaft for proper control of forefoot abduction. Short rear-entry AFO is also designed to control the internal rotation of tibia associated with subtalar pronation. However, the effectiveness of this AFO for tibial control is questionable. In patients with excessive obesity, fixed deformity of the subtalar joint, or tight heel cords, there are not many options other than an AFO. In controlling pronation of the flatfoot, the goal is dampening rather than completely blocking pronation. Completely blocking pronation may lead to other symptoms such as knee or back pain. To avoid irritation of the plantar fascia, the medial arch of the FO or UCBL should not be too prominent.¹⁵ Use of prescribed foot orthoses can be titrated up, starting with 1-2 hours per day to improve patient tolerance.²⁰ Foot orthosis combined with structured exercise programs improve pain and function in flexible flatfoot.²

New treatment techniques for PTT dysfunction include extracorporeal shockwave therapy (ESWT), ultrasound-guided corticosteroid injection, percutaneous needle tenotomy, platelet-rich plasma (PRP), prolotherapy, and potentially in the future, stem cell therapies to promote healing.

Newer materials for orthotics and knowledge of different shoes for different activities are important. Minimally-invasive surgical techniques, such as the previously described subtalar arthroereisis, are emerging but long term outcomes are still uncertain.

Gaps in the Evidence-Based Knowledge

New techniques of pain management of PTT dysfunction include different types of foot orthotics and ankle bracing. The role of PRP, prolotherapy, botulinum toxin, percutaneous needle tenotomy, and stem cells needs to be evaluated. Considerable controversy remains about the appropriate treatment of all stages of PTT dysfunction. The 2024 network meta-analysis on exercise interventions highlighted the benefit of kinetic-chain strengthening but also noted small sample sizes and limited generalizability.¹¹ Comparison-outcome trials are needed to provide better data to evaluate the treatment options. The current controversy in the reconstruction of these deformities is whether to proceed with osteotomies and tendon transfers or arthrodesis. Subtalar arthroereisis is sometimes performed for symptomatic flexible pes planus in pediatric patients but is less common in adults with few studies to assess long-term results.

References

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5. Raj, M. A., Tafti, D., & Kiel, J. (2023). Pes Planus. In StatPearls.
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7. Franco Ah. Pes cavus and pes planus. Analyses and treatment. Physical Therapy. May 1987;67(5):688-694.
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10. Osbeck I, Cöster M, Montgomery F, Atroshi I. Surgically treated adult acquired flatfoot deformity: Register-based study of patient characteristics, health-related quality of life and type of surgery according to severity. Foot Ankle Surg. 2023 Jun;29(4):367-372. doi: 10.1016/j.fas.2023.03.003. Epub 2023 Mar 15. PMID: 36948921.
11. Jia, Y., Sai, X. & Zhang, E. Comparing the efficacy of exercise therapy on adult flexible flatfoot individuals through a network meta-analysis of randomized controlled trials. Sci Rep 14, 21186 (2024).
12. Knapp PW, Constant. D. Posterior Tibial Tendon Dysfunction. StatPearls. May 2019.
13. Mattesi L, Ancelin D, Severyns MP. Is subtalar arthroereisis a good procedure in adult-acquired flatfoot? A systematic review of the literature. Orthop Traumatol Surg Res. 2021;107(6):103002. doi:10.1016/j.otsr.2021.103002
14. Oerlemans LNT, Peeters CMM, Munnik-Hagewoud R, Nijholt IM, Witlox A, Verheyen CCPM. Foot orthoses for flexible flatfeet in children and adults: a systematic review and meta-analysis of patient-reported outcomes. BMC Musculoskelet Disord. 2023 Jan 7;24(1):16. doi: 10.1186/s12891-022-06044-8. PMID: 36611153; PMCID: PMC9825043.
15. Oh-Park M. Use of athletic foot wear, therapeutic shoes, and foot orthoses in physiatric practice. Physical Medicine and Rehabilitation : State of the art review. Vol 15(3). Philadelphia: Hanley & Belfus; Oct 2001. p. 569-585.
16. Arain A, Harrington MC, Rosenbaum AJ. Adult Acquired Flatfoot (AAFD). StatPearls. June 2019.
17. Blasimann A, Eichelberger P, Brülhart Y, El-Masri I, Flückiger G, Frauchiger L, Huber M, Weber M, Krause FG, Baur H. Non-surgical treatment of pain associated with posterior tibial tendon dysfunction: study protocol for a randomised clinical trial. Journal of Foot and Ankle Research. Aug 2015;8(37).
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Original Version of the Topic

David Berbrayer, MD. Pes Planus/Cavus. 9/15/2015.

Previous Revision(s) of the Topic

Mooyeon Oh-Park, MD, Lawrence Chang, DO, MPH, Yusik Cho, MD. Pes Planus/Adult Acquired Flatfoot Deformity. 12/8/2019.

Mooyeon Oh-Park, MD, Emma Desjardins, DO, Areeb Chator, MD. Pes Planus/Adult Acquired Flatfoot Deformity. 1/12/2023

Author Disclosure

Mooyeon Oh-Park, MD
Nothing to Disclose

Simron Gill, MD
Nothing to Disclose

Nicholas Thornton, MD
Nothing to Disclose

Bram Newman, MD
Nothing to Disclose