Surgery for Upper Extremity Neuroma May Relieve Pain, But Often Not Cold Sensitivity
If you've ever been so cold that your fingers tingled or hurt, you know how bad it can feel. Some people, however, don't have to be in extreme cold to feel those sensations. They have what is called thermal hyperalgesia or cold sensitivity. This abnormal pain to the hand and fingers can be very disruptive, taking away enjoyment from activities and also making it hard to do work involving the hands and fingers.

People who have upper extremity injuries (arms, hands, fingers) can develop a nerve injury called a neuroma, a growth of nerve tissue. Forty two percent to 100 percent of people who have this neuroma end up developing cold intolerance. This happens because when there is damage to a peripheral nerve, a nerve not in the spinal cord, the nerve tries to fix itself. To do this, it tries to regenerate and may end up sending axons, nerve fibers, where there shouldn't be any. This can cause sensitivity and pain.

Earlier studies have found that there is a connection between traumatic injury and cold intolerance in the upper extremity, even with amputations and re-attachment of fingers. However, there doesn't seem to be consistency between various studies as to the best way to measure cold intolerance. Some studies depend on questionnaires, while others depend on the patients reporting their symptoms. The authors of this study wanted to clarify the issue by seeing how frequently cold sensitivity occurs in people with neuromas that were caused by injuries, and if the the symptoms improve after surgery to remove the neuroma. They also wanted to see if they could predict who would develop the cold sensitivity.

Researchers sent out questionnaires to 34 patients who were to have surgery to treat a neuroma of the upper extremity. The questionnaires were sent out when the patients were scheduled for their surgery and again three months after their surgery. The patients were followed for about 24 months after. The researchers were looking for information on the age, sex, body size, smoking, employment, which hand was affected (dominant or non-dominant), if they were off work, if there were any law suits involved, and if the patients had had any previous surgeries.

To test for cold intolerance, the patients were asked to complete the Blond McIndoe CISS questionnaire, which asked about symptoms (pain, numbness, stiffness, swelling and change in skin color). They were also asked about the types of pain (spontaneous, on pressure, on movement, or hyperesthesia (intense sensitivity), and they completed the Visual Analog Scale (VAS), which is a scale of zero to 10, with zero being no pain at all and 10 being the most excruciating pain possible. Finally, a questionnaire called the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH), which involves a 30-item disability scale. Each is rated from zero (no disability) to 100 (most severe disability).

Of the original 33 patients, average age 43 years, 18 were men. The length of time that they had pain varied, but it was a mean of 42 months. Twenty-five of the patients reported that their dominant hand was affected by the neuroma. Of all 33 patients, 18 neuromas were the result of a sharp laceration (cut), nine from being crushed, and five from avulsion (tearing away). Twelve patients needed repeat procedures to help treat the neuroma pain and nine patients ended up having a partial finger amputation.

The researchers received questionnaires back from 33 of the patients before the surgery and 30 after the surgery. Before surgery, the problems were reported 28 times for cold-induced pain, 14 times for stiffness, seven times for cold-induced numbness and seven for change in skin color, and two for swelling. Most of these decreased after surgery. The results showed that 91 percent of the patients experienced cold intolerance before they had their surgery, using the CISS scale. After the surgery, there wasn't much difference using this CISS scale, but while they had scored experiencing high pain using the Visual Analog Scale before the surgery, this pain dropped significantly after the surgery.

The authors concluded that while surgery may help relieve the pain of neuromas, the cold sensitivity may not improve. This, unfortunately, is a difficult thing to treat.
Annemieke Stokvis, MD, et al. Cold Intolerance in Surgically Treated Neuroma Patients: A Prospective Follow-Up Study. In Journal of Hand Surgery. Nov. 2009. vol. 34A. Pp. 1689 to 1695.