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Overview of Foot and Ankle Disorders


Kendrick Alan Whitney

, DPM, Temple University School of Podiatric Medicine

Last full review/revision Dec 2019| Content last modified Dec 2019
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Most foot problems result from anatomic disorders or abnormal function of articular or extra-articular structures (see figure Bones of the foot). Less commonly, foot problems reflect a systemic disorder (see table Foot Manifestations of Systemic Disorders).

Bones of the foot

Bones of the foot

Foot Manifestations of Systemic Disorders

Foot Symptoms or Signs

Possible Cause

Pain at rest (feet elevated), relieved by dependency

Cold, red, or cyanotic feet

Advanced arterial ischemia

Episodically red, hot, very painful, burning feet

Erythromelalgia—idiopathic (most commonly) or secondary to various disorders (eg, myeloproliferative disorders, which are rare)

Foot pain that becomes severe within seconds or possibly minutes, particularly in patients with atrial fibrillation; foot often cool

Cyanosis of a single toe (blue toe syndrome)

Thromboembolic disease due to aortic-iliac stenosis, arrhythmia, or cholesterol embolization (after coronary artery bypass or catheterization)

Warfarin therapy

Bilateral or unilateral episodic digital discomfort, pallor, and cyanosis

Bilateral painless cyanosis

Acrocyanosis, drug-induced discoloration (eg, minocycline)

Bilateral edema

Renal, hepatic, or cardiac dysfunction, intra-abdominal venous obstruction

Drugs (eg, calcium channel blockers)

Unilateral edema

Lymphatic obstruction

Firm nonpitting foot and leg edema

Firm, nonpitting edema with nodular appearance above the malleoli

Pretibial myxedema

Edema with hemosiderin deposition and brownish discoloration

Recurrent or prior small-vessel vasculitis

Edema of feet and toes, numbness and pain at the ankle and heel (tarsal tunnel syndrome)

Relapsing symmetric seronegative synovitis (rare)

Red, dusky patches on the dorsum with flaccid bullae (necrolytic acral erythema)


Isolated toe swelling and deformity (dactylitis, or sausage digits) with pain


Painful feet with paresthesias

Peripheral neuropathy (local or systemic—eg, diabetic neuropathy)


Pain or paresthesias in the leg and foot; pain in the foot and back when the leg is extended, relieved when the knee is flexed

Toe, foot, or ankle pain with warmth and redness

Stress fracture, including fragility fractures associated with osteoporosis or repetitive trauma

Foot swelling, redness, and warmth with little or no pain

Neurogenic arthropathy (Charcot joints; usually in the absence of pain)

Posterior heel pain below the top of the shoe counter during ambulation

Tendon tenderness at its insertion (diagnostic)

Exacerbation of tendon pain by passive ankle dorsiflexion

In people with diabetes and people with peripheral vascular disease, careful examination of the feet, with evaluation of vascular sufficiency and neurologic integrity, should be done at least twice a year. People with these diseases should examine their own feet at least once a day.

The feet are also common sites for corns and calluses and infections by fungus, bacteria, and viruses.


Common Foot and Ankle Disorders by Anatomic Site

Ankle (anterolateral)

Meniscoid body

Neuralgia of the intermediate dorsal cutaneous nerve

Peroneal tenosynovitis

Ankle (medial)

Ball of the foot

Interdigital nerve pain (eg, Morton neuroma)

Heel (plantar)

Heel (posterior)

Achilles tendon enthesopathy, fluoroquinolone tendinopathy

Heel (sides)

Plantar arch (sole)

Cuboid subluxation syndrome

Plantar fascial sprain

Posterior tibial tendon rupture with arch collapse


Dactylitis (painful, isolated toe swelling due to inflammatory arthritis)

Hallux rigidus


Disorders Associated With Heel Pain According to Location

Location of Pain

Associated Disorder

Plantar surface of the heel

Plantar fasciosis (plantar fasciitis, calcaneal spur syndrome)

Medial and lateral margins of the heel

In children, epiphysitis of the calcaneus (Sever disease)

Anterior to the Achilles tendon at the retromalleolar space

Fracture of the posterolateral talar tubercle

Posterior to the Achilles tendon

Tendon nodules

Calcaneal insertion or body of the Achilles tendon

Tendon tear (due to trauma or associated with fluoroquinolone use—see Achilles Tendon Tears)


Considerations for Using Corticosteroid Injections

Corticosteroid injections should be used judiciously to avoid adverse effects. Injectable corticosteroids should be reserved for inflammation (such as gout and disorders such as rheumatoid arthritis), which is not present in most foot disorders. Because the tarsus, ankle, retrocalcaneal space, and dorsum of the toes have little connective tissue between the skin and underlying bone, injection of insoluble corticosteroids into these structures may cause depigmentation, atrophy, or ulceration, especially in elderly patients with peripheral arterial disease.

Insoluble corticosteroids can be given deeply rather than superficially with greater safety (eg, in the heel pad, tarsal canal, or metatarsal interspaces). The foot should be immobilized for a few days after tendon sheaths are injected. Unusual resistance to injection suggests injection into a tendon. Repeated injection into a tendon should be avoided because the tendon may weaken (partially tear), predisposing to subsequent rupture.

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