Extra-corporeal Shock Wave Therapy (ESWT)

Extracorporeal Shock Wave Therapy (ESWT), is an innovative non-surgical, cost effective alternative method for the treatment of localized musculoskeletal pain. Since the early 1990's, German investigators have studied the use of shock waves for the treatment of painful musculoskeletal disorders.

Initially, these treatments were administered by modified kidney stone lithotripters. However this was often cumbersome since the kidney stone devices were not designed to treat multiple areas of the body in many different positions. In addition, the kidney stone lithotripters usually delivered relatively high-energy shock waves.

Treatment with these devices therefore was painful and required regional or general anesthesia. It soon became apparent that treatment with lower energy shock waves (much lower than those used to treat kidney stones) was effective in the treatment of musculoskeletal pain. These findings led to the development of the ESWT device, a variable energy shock wave machine made specifically for the treatment of tendinopathies and other specific types of localized painful musculoskeletal conditions.

How It Works

A shock wave is generated at the base of the shock tube by an electromagnetic acoustic source. When a voltage pulse from a capacitor reaches an aluminum membrane, the membrane is repelled causing a shock wave to course through a water filled generator. The shock wave moves through the water into an acoustic lens. The lens then focuses the energy of the shockwave on a concentrated point at a fixed distance from the lens.

Indications

Chronic pain associated with tendinitis of the shoulder, elbow, knee and foot were the first conditions treated by ESWT. Through clinical trials on various foot problems, ESWT has been found to be effective in treating plantar fasciitis (heel spur syndrome) and achilles tendinitis, when all forms of conservative therapy have failed to alleviate the condition. Most insurance companies that cover ESWT will expect to see at least a 6 month attempt at conservative therapy before approving this modality.

Low Energy vs. High Energy ESWT

There are presently 2 types of ESWT in use for foot problems; a high energy shock wave and a low energy shock wave. The high energy shock wave usually requires only one treatment session of approximately 45 minutes. Anesthesia is required during this procedure because the high energy shock waves would otherwise be very painful to endure. A period of pain and soreness may also ensue post treatment requiring rest and analgesics. The low energy shock wave usually requires three separate sessions to accomplish. It does not produce pain during the procedure making anesthesia unnecessary. In addition, the patient may walk the same day. The use of low energy has significant advantages over high energy shock wave applications. These include:

1. The ability to treat patients without the necessity of regional or general anesthesia.
2. Reducing the clinical risk of tissue injury or bleeding into the skin, joint, or other tissues near the area being treated.
3. Allowing highly individualized treatment at the exact site of pathology by allowing the use of precise clinical focusing rather than depending upon imaging with ultrasound, fluoroscopy, or x-ray that may not adequately identify the exact site of the problem.

Within the low energy range of energy treatment levels, the ability to adjust this level to each patient’s tolerance adds to the concept of individualized treatment and safety. Although the use of low energy may require more treatment sessions than higher energy the reduced cost of eliminating the anesthesia and imaging expense allows the treatment to be more cost effective.

Because of these factors, we have been treating our patients with the low energy shock wave machine and have found it to be a very safe and comfortable therapy.