FDA today approved a medical device that uses shock waves to relieve chronic heel pain. Shock wave treatment has been used for 10 to 15 years to break up kidney stones without surgery.

The new device, the OssaTron, made by HealthTronics Inc. of Marietta, Ga., was approved to treat chronic proximal plantar fasciitis, a condition that causes severe pain in the heel of the foot. Plantar fasciitis is usually caused by an inflammation of the foot’s tissue. Plantar fasciitis is typically treated with physical therapy, pain relievers, cortisone injections, use of heel-cushions in shoes, and in severe cases, with surgery.

The new device was approved for use on adults who have had plantar fasciitis for at least six months and have tried other standard methods for treating it, with little success. The OssaTron is a shock wave generator. The shock waves are created by a spark plug enclosed in a soft plastic dome filled with water. During treatment, the dome is placed closely against the heel so that the shock waves pass through the dome to the heel. Treatment is performed as an outpatient procedure and a total of 1500 shocks are usually delivered. Approval of the product was based on a review of clinical studies of safety and effectiveness conducted by HealthTronics and on the recommendation of the Orthopedics and Rehabilitation Devices Panel of FDA’s Medical Devices Advisory Committee.

HealthTronics studied 302 people with chronic pain who had failed other treatments in the previous six months. Half were treated with the OssaTron; half received a sham treatment. All were given a local anesthetic or an ankle block before treatment. Patients were followed for three months. Most patients (60%) treated with the OssaTron reported that they experienced some improvement in pain; 48% of those treated with the sham said they experienced some improvement in pain.

Complications included mild neurological symptoms in 6 patients (2%) and plantar facial tears (tears in the tissue in the bottom of the foot) in 2 patients (0.6%). As a condition of approval, FDA is requiring HealthTronics to conduct a study to further evaluate the problems of neurological symptoms and plantar fascial ruptures.