Plantar fasciitis, the most common cause of heel pain, is caused by a noninflammatory structural degeneration of the plantar fascia.
Severe onset of medial heel pain after prolonged periods of inactivity such as sleeping or standing is often complained by patients. Heel pain is unilateral in 70% of cases  and usually resolves spontaneously after a few minutes of walking and often recurs later in the day after an extended idle period. There may be accompanying tenderness localized along or proximal to the plantar fascia .
Nocturnal pain is not a common presentation of PF. The presence of this should raise suspicion of other causes of heel pain, such as tumors, infections, and neuralgia (including tarsal tunnel syndrome) . Sensory disturbances (i.e. radiation of pain) are uncommon. This generally points to a neurologic pathology and is important to exclude.
A careful history taking should be done as PF is often diagnosed clinically. Extraction of information about predisposing factors is tantamount. Some factors that may play a role in PF are:
Physical examination of the lower extremity should include measurement of the foot and ankle ROM (especially ankle dorsiflexion), palpation of the heel and plantar fascia, observation of swelling or atrophy of the heel pad, presence of hypesthesias or dysthesias, assessment of the architectural alignment of the foot, and angle and base of gait evaluation. The quality and height of the plantar fat pad also have been implicated as factors in plantar heel pain .
Localized tenderness can be elicited at the anteromedial aspect of the calcaneus. Exacerbation of pain may be present with passive dorsiflexion of the toes (sometimes called as windlass test) or having the patient tip-toe. Tightness of the Achilles tendon (with dorsiflexion at the ankle limited by 10° or more) is found in almost 80 percent of patients .
Tenderness over the plantar surface, third , and fourth metatarsal heads is not a common finding in PF. Morton’s neuroma will commonly have this presentation as a result of entrapment of the medial and lateral plantar nerves.
The tenderness in Achilles tendinitis is usually proximal to the site of injury on the gastrocnemius-soleus area. A Thompson test must be done to rule out tendon rupture. The test is usually done with the patient in prone and knees flexed. The belly of the gastrocnemius is squeezed to determine integrity of the Achilles tendon. Plantar flexion of the foot upon squeezing means the tendon is intact.
Ancillary tests are not necessary for diagnosing PF per se. Diagnosis of PF is usually done with thorough history taking and complete physical examination. Diagnostic imaging is rarely indicated for initial evaluation and treatment but may be helpful in certain cases to rule out other causes of heel pain . Underlying infections, tumors, or fractures can be visualized with various imaging modalities.
Ultrasonography is a useful tool to diagnose PF . It is often the initial imaging modality of choice when necessary. Ultrasound typically reveals increased thickness of the fascia usually near the origin. Hypoechoic changes are also seen in the involved part . In case of plantar fascia tear, increased vascularity within the area is visualized with a Doppler ultrasound.
Weight-bearing radiographs are preferred because it may provide biomechanical interpretations and insight to anatomical deviations. An infracalcaneal spur frequently is associated with the symptomatology of plantar fasciitis, although its presence or absence may not necessarily correlate with the patient’s symptoms . Radiographic identification of a plantar heel spur usually indicates that the condition has been present for at least 6 to 12 months, regardless of presence of symptoms.
MRI is very sensitive in detecting edema of the fascia, which appears as a poorly marginated area of high signal intensity. MRI can also detect plantar fascial thickening. This is usually seen in the calcaneal insertion and is fusiform-shaped .
Nerve entrapment can be visualized through electromyography (EMG). Changes in action potential amplitude can be seen.
PF is often a self-limiting condition. However, spontaneous resolution takes a long process and occurs anywhere between 6-18 months . Patients usually have a clinical response within 6 weeks after initial treatment. The initial treatment must be continued until symptoms are resolved. If little or no improvement is noticed, the patient should be referred to a foot and ankle surgeon .
Surgery is rarely necessary and consists of releasing a portion of the plantar fascia (fasciotomy) along with decompression of the lateral plantar nerve for open surgical procedures .
Current practice favors a minimally invasive approach to plantar fasciotomy versus extensive open surgical exposures [25, 26].
The etiology of PF is poorly understood with 85% of cases still attributed to unknown cause. It is likely the result of multiple internal and external factors. Recent case-controlled studies have identified obesity or sudden weight gain, reduced ankle dorsiflexion, pes planus, and occupations that require prolonged weight-bearing as the greatest risk factors associated with PF .The most accepted theoretical cause of PF is repetitive microtrauma to the plantar fascia.
Immobility for long periods of time, obesity, and pregnancy place the muscles, ligament, and fascia for arch support under excessive strain. Excessive strain causes the muscles to fatigue. When this happens, the ligaments and fascia stretch and pain sets in .
People with occupations requiring prolonged weight-bearing, such as military personnel, waitress, or nurse, have long been considered at risk of PF because of the repetitive tensile load placed on the fascia [10, 11].
Obese individuals with a body mass index (BMI) > 30 kg/m2 had an odds ratio of 5.6 for PF compared to those with a BMI ≤ 25 kg/m2 .
Reports show that 81-86 percent of individuals with symptoms consistent with PF have excessive foot pronation. After the heel strike of gait, the tibia turns inward and foot pronates which stretches the plantar fascia and flattens the arch  . Overpronation contributes to excessive foot mobility. The foot responds to the additional tissue stress through plantar fascia elongation .
Reduced ankle dorsiflexion
Reduced ankle dorsiflexion indicates decreased flexibility of the gastrocnemius and Achilles tendon. This results to compensation of the plantar fascia during propulsion.
The mean normal range of motion (ROM) for ankle dorsiflexion is 10°. ROM of <10° of ankle dorsiflexion had an odds ratio of at least 2.1 for PF. The ratio increased dramatically as the range of dorsiflexion decreased .
Individuals with pes planus (flat foot) are thought to be at greater risk for PF  . Pes planus is a condition in which the medial longitudinal arch is collapsed. As a result, the body forces it weight directly downward and medially between the calcaneum and the navicular bone. Over time, the plantar, calcaneonavicular, and medial ligaments of the ankle joint become permanently stretched, and the bones change shape . The muscles and tendons lengthen permanently and biomechanics of gait are disrupted. Poor gait mechanism disables effective distribution of tensile forces to the feet; consequently, pain is produced.
Other potential anatomical risks that alter proper biomechanics include leg length discrepancy, excessive lateral tibial torsion, and excessive femoral anteversion .
There appears to be a direct relationship between PF and overtraining and training errors. Sudden increases in weight bearing activity, particularly those involving running, can cause micro-trauma to the plantar fascia at a rate that exceeds the bodyʼs ability to recover . Training on unyielding surfaces, such as uphill, downhill, or uneven surfaces, force the plantar fascia to absorb stress beyond its normal capacity.
Improper or excessively worn footwear produce heel pain. Shoes should only be used for activities it is specifically designed for. They should provide adequate arch support and heel cushion. Worn or ill-fitting shoes aggravate PF due to lack of proper cushioning and shock absorption; consequently, a new pair of shoes can decrease foot pain significantly .
In the United States of America alone, more than two million individuals are undergoing treatment for PF on an annual basis. The chronic condition accounts for 11 to 15 percent of professional visits related to foot pain .
It is estimated that 10 percent of the U.S. population will experience plantar heel pain during the course of a lifetime .
PF affects individuals regardless of sex, age, ethnicity, or activity level. It is mostly seen in physically active individuals such as runners and military personnel but is also prevalent in the general population, particularly in women ages 40-60 .
The most common cause of PF is biomechanical stress . Mechanical overload, whether the result of biomechanical faults, obesity, or work habits, may contribute to the symptoms of heel pain   .
Repetitive stress stretches the fascia, ligaments, and muscles and weakens arch support. Heel pain becomes a consequence of this compensatory mechanism. Localized nerve entrapment of the medial calcaneal or muscular branch off the lateral plantar nerve may also be a contributing factor to the heel pain .
PF is a degenerative syndrome of the plantar fascia resulting from repetitive trauma of the plantar fascia at its enthesis  or increased load-bearing  such as in obesity. The term is somewhat a misnomer since fasciitis means that there is an inflammatory component of the condition.
Recent studies suggest that PF manifests non-inflammatory and degenerative processes   . Moreover, biopsy specimens of the affected tissue reveal degenerative changes in the fascia with or without fibroblastic proliferation and chronic inflammatory changes . Therefore, the term plantar fasciosis has been advocated to avoid association with an inflammatory component and reiterate the degenerative nature of histologic observations at the calcaneal insertion  . Fasciosis is pathology of chronic degeneration without inflammatory process.
There are no guidelines for prevention of PF.
Heel pain is among the most prevalent complaints of patients. There is an abundance of differential diagnosis for heel pain. The major cause of heel pain is mechanical in origin although arthritic, neurologic, traumatic, or systemic origin can be taken into consideration . Plantar heel pain may be seen in up to 11% to 15% of adults .
The most common cause of plantar heel pain in adults is plantar fasciitis (PF). Other names for PF include painful heel syndrome, heel spur syndrome, runnerʼs heel, subcalcaneal pain, calcaneodynia, and calcaneal periostitis . PF should not be confused with bone spurs. The latter is an ossification in the posterior attachment of the fascia resulting from frequent bouts of PF .
Plantar fascia or plantar aponeurosis is a triangular-shaped sheet of connective tissue. It is a thickening of the deep fascia of the foot and occupies the central area of the sole .
The apex or origin of the aponeurosis is attached to the medial and lateral tubercles of the calcaneum. The base of the aponeurosis fans out into five slips at the base of the toes. Each slip divides into a superficial and deep band. The superficial band invests into the skin. The deep band goes to the root of the toe where it divides into two parts. These parts straddle the flexor tendons and join the fibrous flexor sheath and deep transverse ligaments.
The plantar fascia divides into the medial, lateral, and central sections laterally. The central portion is the most important section attached to the medial calcaneus. The medial section lie on top of the big toe abductors while the lateral section superimposes the little toe abductors.
The functions of the plantar aponeurosis are the following: to give firm attachment to the overlying skin; to protect the underlying vessels, nerves, and tendons and their sheaths; and to assist in maintaining the medial and longitudinal arches of the foot . It does not serve any purpose in normal static support of arches. The plantar fascia acts as the dynamic shock absorber of the foot and leg during walking or running. Together with the plantar and calcaneonavicular ligaments and the peroneus, tibialis, and small foot muscles, it adjusts the arch to accommodate irregular surfaces and absorb stress.
The aponeurosis also plays a role in propulsion. It lengthens during the heel-off phase of the gait cycle to store potential energy. During the toe-off phase, it passively contracts and converts the stored energy into kinetic energy; thereby, imparting greater foot acceleration .
In the presence of aggravating factors, the repetitive movement of walking or running can cause micro-tears in the plantar fascia. The affected site is frequently near the origin of the plantar fascia at the medial tuberosity of the calcaneus .
Patients should be regularly advised that plantar fasciitis treatment is a very long process. Treatment assignments such as plantar fascia stretching should be done religiously to avoid setbacks. Emphasis on the consequences of long-term use of NSAIDs should be done as well.
The following recommendations should be done:
The most fundamental treatment of choice is rest and avoidance of aggravating factors. Significant improvement with rest is seen in up to 25% of PF patients.
Leaning wall stretch
A tennis ball will be useful for this exercise.
Ball-rolling exercises stretch the plantar fascia and relieve pain.
Towel curls strengthen the small muscles of the feet
Losing weight will decrease the tensile stress imposed upon the feet, which will cause relief.
Worn out shoes lose their cushioning and protective properties. New shoes decreases heel pain in 14% of PF patients.
Avoid exercising on pavements and uneven surfaces
Jogging on the road may be good for the heart but it will cause micro tears to the foot. Try alternating jogging with other cardiovascular activities such as biking or swimming.
Avoid walking barefoot
Walking barefoot punishes the feet by letting it absorb 100% of mechanical stress. Use shoes or flip-flops and experience pain relief.
Arch support insoles
For people with flat feet, arch support insoles will provide better cushioning and proper mechanics of the feet. Thereby, heel pain is avoided.