Standard treatments of plantar fasciitis include stretching exercises of the posterior muscle chain and plantar fascia, taking anti-inflammatories, cortisone infiltration or biostimulation with physical therapies (low energy laser therapy, shock waves, ultrasound therapy, etc.). In non-responsive forms to conservative treatments, surgical treatment can be undertaken.

Laser therapy is indicated for plantar fasciitis, in particular for its biological anti-inflammatory, anti-edema and reparative effects on the plantar fascia; to date, the potential effects also on the underlying bone edema component, when present, which aggravates and self-maintains the ongoing pathology are not known.

Plantar fasciitis is one of the most common causes of heel pain; the pain is more intense in the morning, tends to decrease during the day with movement, to flare up after sitting for a long time. It presents itself as inflammation and contextual degeneration of the insertion of the fascia that covers the muscles present at the level of the sole of the foot, with progressive evolution and possible calcification of the insertion. The incidence is between 9 and 20% of the population, with a higher incidence in middle-aged obese women and in young male runners. The diagnosis makes use of radiography, to verify any local deformities or the presence of the subcalcaneal spur, and ultrasound, to investigate the integrity of the fascia and its thickening. MRI images are useful for better studying the heel bone and plantar fascia, especially for discerning other various causes of heel pain, including stress fractures, tarsal tunnel syndrome, and Achilles tendinopathy. Signal changes with bone edema are sometimes found in association with plantar fasciitis and may be indicative of or represent the result of avulsive trauma, stress, intraspongious fractures or a combination of these situations. These MRI images are similar to those described in the elbow in some patients with epicondylitis, where overuse can cause increased bone edema on T2-weights. Previous studies have shown the presence of bone edema at the level of the heel on MRI in 35% of patients with plantar fasciitis. Plantar fascia evaluation with a dedicated magnetic resonance scanner in weight-bearing position: our experience in patients with plantar fasciitis and in healthy volunteers. Maier et al demonstrated that the presence of calcaneal bone edema is a highly predictive factor for improved response to shock wave treatment. Often the finding of a thickening of the fascia and the signal changes of the soft tissues do not correlate with the clinical response, while the presence of bone edema is highly predictive (positive predictive value 0.94, sensitivity 0.89, specificity 0.8).

Inclusion Criteria:

1. history of heel pain for at least 3 months prior to enrollment,
2. Pain on palpation of the medial calcaneal tubercle or proximal plantar fascia,
3. plantar fascia thickness of 4.0 mm or greater.

Exclusion Criteria:

1. age below 18 years of age
2. history of systemic disease
3. pregnancy
4. Previous surgery on the lower limbs
5. diagnosis of fibromyalgia, neurological disease, Achilles tendinopathy, metatarsalgia, acute ankle sprain, tarsal tunnel syndrome, or heel joint syndrome
6. body mass index (BMI) greater than 35 kg/m2
7. wounds, infections in the treatment area
8. altered sensation in the treatment area
9. skin pigmentation alterations in the area to be treated (tattoo, dyschromia)
10. metal implants in the treatment area
11. History of oral or injected corticosteroid therapy within the past six weeks
12. Diagnosis of neurological heel pain (radiculopathy)
13. diagnosis of systemic inflammatory arthritis (rheumatoid arthritis, etc.)
14. other acute pathologies (febrile fever, cold, etc.) requiring treatment
15. other painful conditions requiring painkillers (toothache, back pain, etc.)
16. neoplasms
17. cardiac pacemaker or other device.