Phantom pain is a pain that is felt in a limb that has been amputated. The person who is feeling the pain actually feels a burning, stinging, cutting, or even itching sensation, even though the limb is not physically there.

Illness behavior is a part of human illness. However, it can be out of proportion to the physical problem and then becomes counter productive. Illness behavior can be an expression of emotional or psychological distress that some conclude can be important in the development and maintenance of chronic pain.

Apeldoorn et al. The reliability of nonorganic sign-testing and the Waddell score in patients with chronic low back pain. SPINE. Volume 33. Number 7. Pp. 821-826.

Yes, because a drug may be beneficial to a small proportion of people who are responders, present study designs may dilute results due to the non-responders. The authors of a recent study suggest the use of a study design called enriched enrolment with randomised withdrawal, EERW. In this study design, subjects are tried on a drug first, and only those who have a positive response are then randomised to study it further.

H.J. McQuay et al.

The authors of this study suggest that enriched enrolment with randomised withdrawal (EERW), be used in drug studies, particularly analgesics for chronic pain patients. Individual response to a drug can be influenced by genetic differences, particularly in the metabolism of drugs. The authors feel that conventional clinical trials may not be adequate in assessing efficacy of a certain drug given some subjects may be non-responders to the drug.

With the increase in use of intrathecal pain pumps for pain and spasticity, the author of a recent report highlights that there is a small but significant number of problems due to their use. One such complication is the formation of an inflammatory mass called a granuloma at the tip end of the catheter. The catheter tip is placed in the spinal canal so in some cases has caused neurological problems such as weakness and even paralysis.

Presently, morphine and ziconotide have been approved for delivery by intrathecal pump for pain. Baclofen has been approved for intrathecal delivery for spasticity. Doctors often use medications in the intrathecal pump that have not been approved by the FDA but seem to be safe and effective.

T. Agres, As use of pain pumps expands, scope of problems with devices becomes clearer. Pain Medicine News. Vol.6:03, 2008.

There are various problems associated with the use of intrathecal pumps. Withdrawal from the delivered medication, accidental over sedation or overdose are often caused by human error. Withdrawal can happen when the amount of medication remaining in the pump is miscalculated and runs out. Delivering too much medication can result in accidental over sedation or even overdose. The pump itself can malfunction. Newer units are proving to be more reliable however.

An original study that took place in the United States, has since been replicated with similar findings in the United Kingdom. This study, as well as other studies, demonstrate that chronic pain exists in other countries.

K.M. Dunn et al. A prognostic approach to defining chronic pain: Replication in a UK primary care low back pain population. PAIN 2008. Vol. 135. Pp. 48-54.

Whether or not someone will have chronic back pain does not necessarily depend on the severity of pain. Studies show that psychological factors such as depression, stress, and focus on body symptoms can influence the degree, duration, and debilitation associated with the pain.

K.M. Dunn et al. A prognostic approach to defining chronic pain: Replication in a UK primary care low back pain population. PAIN 2008. Vol. 135. Pp. 48-54.

Yes, there is. The Food and Drug Administration, FDA, approved one in 2004 for use in the United States. While their initial cost is greater, these units are projected to last ten to 25 years, providing a substantial cost savings over the course of a lifetime.

Hornberger, J. et al. Rechargeable spinal cord stimulation versus nonrechargeable system for patients with failed back surgery syndrome: A cost-consequences analysis. Clin J Pain. 2008. Vol. 24, Num.3. Pp. 244-252.