Shock Wave Therapy for Plantar Fasciitis
Plantar fasciitis is a painful condition affecting the bottom of the foot. It is a common cause of heel pain and is sometimes called a heel spur. Plantar fasciitis is the correct term to use when there is active inflammation.
Plantar fasciosis is more accurate when there is no inflammation but chronic degeneration instead. Acute plantar fasciitis is defined as inflammation of the origin of the plantar fascia and fascial structures around the area. Plantar fasciitis or fasciosis is usually just on one side. In about 30 per cent of all cases, both feet are affected.
The natural history of this condition is that left alone (untreated), it will eventually go away on its own. Another term for this kind of response is to say that plantar fasciitis is usually self-limiting. That's why many studies using a placebo (pretend treatment) get good results no matter how it's treated.
But sometimes, the problem lasts a long time. When it doesn't go away, doctors say it's recalcitrant, which means it's chronic. The painful symptoms limit movement and function, which can reduce quality of life. Finding a way to treat patients with chronic plantar fasciitis is important.
In this study, the use of radial extracorporeal shock wave therapy (rESWT) was compared with a placebo treatment in patients with recalcitrant plantar fasciitis. Shock wave therapy is a newer form of nonsurgical treatment. It uses a machine to generate shock wave pulses to the sore area. Radial shock waves apply the energy at a specific point of tenderness and then the force of the vibration spreads out over a larger area. The pattern of vibrational energy released looks like the shape of a megaphone.
The study design of this research project was a double-blind, randomized, placebo-controlled trial. Double-blind means the patients didn't know if they were receiving a real rESWT session or a placebo. The physicians evaluating and following up with the patients didn't know which group the patients were in either. Only the orthopedic surgeon or podiatrist administering the treatment knew who was getting which treatment. Randomized means the group they were assigned to was chosen at random by a computer program. The control group received the placebo treatment.
Everyone in the study had a history of chronic plantar fasciitis for at least six months. All other conservative (nonoperative) care had not been successful in reducing the painful symptoms. Drug (pharmacologic) treatment and nonpharmacologic treatment were tried. Nonpharmacologic intervention included steroid injection(s), stretching, night splints, ultrasound, ice, massage, electrotherapy, and/or orthotics (shoe inserts). In order to be included in the study, the pain was rated as at least a five on a scale from zero (no pain) to ten (worst pain).
Each person enrolled in the study was given three treatments (either rESWT or placebo). The sessions were given two weeks apart. The patients were followed for 12 months after the last treatment. The first follow-up check-up was 2 weeks after the third treatment. If the pain was unchanged, they were allowed to seek other forms of treatment. In other words, they didn't have to suffer a full 12 months just to complete the study if the treatment they received wasn't working.
The same experiment was carried out in eight different treatment centers (in the USA and Europe) as part of an FDA approval study. This type of design is referred to as a parallel group design. Treatment effectiveness was measured based on patients' reports of heel pain with the first steps of the day when plantar fasciitis is usually the most symptomatic.
Pain during daily activities and with pressure placed on the heel were also used as measures of change. A special device called a Dolormeter was used to apply local pressure to the bottom of the foot. The amount of pressure needed to reproduce the pain was measured and recorded for each patient. Patient satisfaction and function were tested using several patient surveys. This gave a separate way to measure effectiveness of the treatment other than just pain. These are referred to as secondary outcome measures.
The results showed much better outcomes with rESWT compared with placebo treatment. And the patients who received rESWT continued to improve up to the 12-month check-up. This shows that rESWT gives stable results that last. All results (primary and secondary outcome measures of reduced pain, improved function, increased patient satisfaction) favored rESWT. Patients receiving rESWT rated the treatment as very tolerable.
The authors conclude by saying rESWT is a safe and effective outpatient treatment that works quickly and offers patients an alternative to surgery. Athletes with plantar fasciitis can get back to their sports participation without delay. It is recommended for patients who have not benefited from other types of conservative care before considering surgery as the next treatment option.
Ludger Gerdermeyer, MD, PhD, et al. Radial Extracorporeal Shock Wave Therapy Is Safe and Effective in the Treatment of Chronic Recalcitrant Plantar Fasciitis. In American Journal of Sports Medicine. November 2008. Vol. 36. No. 11. Pp. 2100-2109.