Effect of Extracorporeal Shockwave Therapy on Gait Parameters in Patients With Planter Fascitis

Plantar fasciitis with an accompanying heel spur is very burdensome and difficult to treat disease. It most often arises as a result of degenerative changes of the proximal plantar fascia and the tissues surrounding the aponeurosis, occurring due to continuous irritation of the area and resulting micro-injuries. The main symptom of plantar fasciitis is pain in the heel area; this worsens over time, increasingly occurring upon loading and eventually, even at rest. Redness and swelling are also observed in the heel. The risk of the disease is increased by being overweight, working a job that requires long periods of standing, lifting heavy objects.

About 85% to 90% of patients do not need to undergo surgery, and 80% of patient do not experience pain relapse after conservative treatments. Minimally invasive treatments commonly used for treating PF are extracorporeal shockwave therapy (ESWT), corticosteroid (CS)injections, platelet-rich plasma (PRP) injections, botulinum toxin (BTX), acupuncture, dry needling and prolotherapy.

Conservative treatment options for PF include rest, weight loss, non-steroidal anti-inflammatory drugs, physical therapies (ultrasound therapy, low-energy, and laser therapy), plantar fascia and calf muscle strengthening and stretching exercises. If symptoms persist, second-option treatment is usually local corticosteroid injections. However, despite providing a good effect in terms of pain reduction, corticosteroids have proven to damage the fascial tissue, thus increasing the risk of further degeneration and eventual rupture. To avoid this complication, Extracorporeal shock wave therapy (ESWT) is a treatment recommendation for patients with chronic PF recalcitrant to other conservative treatment.

Extracorporeal shockwave therapy (ESWT) is a physical therapy that generates three-dimensional pressure pulses, lasting microseconds and reaching peek pressures of 35-120 MPa, and has effects depending on intensity, pulse cycle and shockwave (SW) modality. We have two modalities of SW therapy: focused shockwave (FSW) and radial shockwave (RSW). FSW is documented as a possible alternative to the surgical approach: it focuses on a small area (2 to 8 mm) and penetrates at a selected depth, having effects that depend on the energy delivered to the focal area; that is why it is important to know the energy flux density (EFD), which is considered the "dose" of SW administered.

RSW produces SW that are transmitted radially and do not have penetrating effects on tissue, acting superficially. They are frequently used in soft-tissue pathologies and, recently, also in plantar fasciitis. As this physical therapy is widely used for the treatment of plantar fasciitis. The mechanism of ESWT is not completely clear. However, it is speculated that ESWT may produce a reflexive analgesic effect by inducing excitability of the axon and destroying unmyelinated sensory fibers.

Due to the negligible side effects, which only relate to minor referred pain during ESWT sessions and minor hematoma, this therapy represents a safe, advantageous, and well-tolerated approach without surgical risks or severe complications. Therefore, the use of ESWT has gained increasing popularity for treating different musculoskeletal disorders. These encompass tendinopathies (both calcifying and non-calcifying), plantar fasciitis (PF), lateral epicondylitis ("tennis elbow"), greater trochanteric pain syndrome, bone nonunion fractures, and joint diseases including avascular necrosis.

The extracorporeal shock wave produces a treatment effect by passing through muscle and adipose tissue and releasing energy at the border of the bone due to the difference in impedance. Therefore, ESWT improves the clinical condition of the plantar fascia. Thus, the benefits of ESWT may be fundamentally more difficult to achieve in patients with pain throughout the entire plantar fascia when the ESWT target site is far from the enthesis of the calcaneus. Furthermore, the investigators speculate that the ESWT effect may be insufficient in patients with degeneration of the plantar fascia itself.