Background
Plantar heel pain is a commonly encountered orthopedic problem that can cause significant discomfort and a limp because of the difficulty in bearing weight. The etiologies of this condition are multiple; therefore, a careful clinical evaluation is necessary for its appropriate management. Nonsurgical or conservative care is successful in most cases. [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
Pathophysiology
The specialized soft tissue at the heel functions as a shock absorber. The subcutaneous structure consists of fibrous lamellae arranged in a complex whorl containing adipose tissues that attach with vertical fibers to the dermis and the plantar aponeurosis. [11]
The heel can absorb 110% of the body's weight during walking and 200% of the body's weight during running. The plantar fascia is a multilayered fibroaponeurotic structure that arises predominantly from the medial calcaneal tuberosity and inserts distally through several slips into the plantar plates of the metatarsophalangeal joints, the flexor tendon sheaths, and the bases of the proximal phalanges of the toes.
Dorsiflexion of the toes applies traction stress at the origin of the plantar fascia. A contracture in the triceps surae, a pes cavus, or a pes planus can increase the traction load at the origin of the plantar fascia during weightbearing activities.
Other anatomic factors that can have similar effects are overpronation, discrepancy in leg length, excessive lateral tibial torsion, and excessive femoral anteversion. However, overuse, not anatomy, is the most common cause of plantar fasciitis in athletes. The pain of plantar fasciitis is caused by collagen degeneration associated with repetitive microtrauma to the plantar fascia.
An inflammatory response and reparative process can double the thickness of the plantar fascia, which is normally approximately 3 mm. Biopsy specimens reveal collagen necrosis, angiofibroblastic hyperplasia, chondroid metaplasia, and calcification.
The heel pain can also have a neurologic basis. The tibial nerve, with nerve roots from L4-5 and S2-4, courses in the medial aspect of the hindfoot, through the tarsal tunnel, under the flexor retinaculum, and over the medial surface of the calcaneus. The calcaneal branch, arising directly from the tibial nerve, carries sensation from the medial and plantar heel dermis.
The tibial nerve divides into lateral and medial plantar nerves, which proceed into the plantar aspect of the foot through a foramen within the origin of the abductor hallucis muscles, which forms the distal tarsal tunnel. The first branch of the lateral plantar nerve changes course from a vertical to a horizontal direction around the medial plantar heel. It passes deep to the abductor hallucis muscle fascia and the plantar fascia and is the nerve supply to the abductor digiti minimi. The tibial nerve and its branches in the hindfoot can be involved with compressive neuropathies. A valgus heel can stretch in the tibial nerve.
Etiology
Local causes include the following:
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Proximal plantar fasciitis
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Fat pad atrophy
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Plantar fascia rupture
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Tarsal tunnel syndrome
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Compression of the first branch of the lateral plantar nerve
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Plantar fasciitis coexisting with compression of the first branch of the lateral plantar nerve
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Stress fracture of the calcaneus
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Bone tumor or bone cyst
Regional causes include the following:
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Prolapsed intervertebral disk
Systemic causes include the following:
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Inflammatory bowel disease–associated arthritis
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Seronegative spondyloarthropathies
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Inflammatory arthritis (ie, rheumatoid arthritis)
Epidemiology
Although the exact prevalence of plantar heel pain is unknown, it is estimated that more than 2 million Americans seek treatment for plantar heel pain each year. [12] The prevalence in active and military populations is especially high. [13] Internationally, in both athletic and nonathletic populations, the incidence of plantar fasciitis is reported to be approximately 10%.
The average age of a patient with proximal plantar fasciitis is approximately 45 years. There is a known sex-based dimorphism in presentation, with proximal plantar fasciitis being twice as common in women as in men.
Prognosis
Proximal plantar fasciitis is successfully managed with conservative care in approximately 90% of cases. In general, the longer the duration of symptoms, the longer it takes for the patient to obtain complete pain relief. [14]
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Soft heel cushion to absorb shock.
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Soft heel cushion and a cup.
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Custom-molded orthotic.
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Stretching exercise. Lean against the wall with the knee kept straight and the heel touching the floor.
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Stretching the back of the leg at the edge of a stair.
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Massaging and stretching the plantar fascia using a can.
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A night splint applied on back of the leg and foot.
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A night splint applied on the front of the leg.
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Lateral radiograph of the hindfoot showing a cyst in the anterior aspect of the calcaneus in a 19-year-old patient who presented with heel pain.
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Plantar fascia tissue-specific stretching exercise
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Edema localized to plantar heel on the left foot in a patient with calcaneal stress fracture compared to the normal right heel
