Dr. Christopher J. Winfree of The Center for Peripheral Nerve Surgery and his colleagues describe in a paper, soon to be published in the journal Neurosurgery, how the innovative use of ultrasound can guide surgeons in the placement of a pain relieving device for a patient with intractable foot pain.

The patient, we’ll call “Mildred”, suffered for years with plantar fasciitis.  This causes pain on the bottom of the foot, especially the heel.  She had extensive physical therapy and two foot surgeries and nothing helped relieve her pain.  When all else fails with a patient like this, Neurosurgeons can place an electrical nerve stimulation (ENS) device in the spine to block the pain.

ENS devices work, essentially by introducing pressure and vibration to mask pain. You are doing the same thing when, after bumping into a coffee table, you rub your shin to make it feel better.  When this kind of stimulation is effective, permanent implantation can be an option.

A neurosurgeon can map which nerve is associated with the pain and place an ENS device on it.  All the nerves in our arms and legs travel to and from our brain. They travel from our brain, like electrical wires coming from a main frame, through our spinal cord and out to their assigned locations. The brain and spinal cord make up what is called the central nervous system, and all the nerves once they exit the spine are called the peripheral nervous system. The central nervous system is more delicate so surgeons prefer to work with peripheral nerves.  The most common place to put an ENS device is in the patient’s back where the peripheral nerve starts.

Mildred had this procedure done four times and it failed four times because of infection.  Surgeons at The Center for Peripheral Nerve Surgery knew they had to find a location further along the nerve pathway.  The perfect location was in the back of her knee.

Typically, surgical placement of an ENS unit there involves opening up the back of the knee, treading through muscles, arteries and veins to find the nerve they are looking for.  At this point in Mildred’s ordeal, however, doctors wanted to limit the amount of trauma they had to put her through so they used an innovative technique using ultrasound.

Most of us know what an ultrasound is; something doctors use to see a baby.  Instead of using it on Mildred’s belly however, they used it on her knee.  Ultrasound images were used like a camera and required only a tiny incision and a hollow needle.  Doctors threaded the ENS unit through the needle and attached it right where they wanted it.  It didn’t take Mildred long to recover and she finally got the relief she needed.

Look for Dr. Winfree and his colleagues’ paper, Ultrasound-Guided, Percutaneous Peripheral Nerve Stimulation: A Technical Note in an upcoming issue of Neurosurgery