Facilitation of percutaneous trial lead placement with ultrasound guidance for peripheral nerve stimulation trial of ilioinguinal neuralgia: a technical note.

Introduction. Peripheral nerve stimulation (PNS) has been used for many years to treat neuropathic pain syndromes. Technical advances in neurostimulation hardware have led to a renewed interest in the use of PNS for control of intractable pain caused by peripheral mononeuropathies. One such application includes intractable groin pain. This study identified two patients with chronic groin pain, secondary to trauma, referred for interventional pain management. For each patient, PNS trial was attempted using ultrasound guided localization of the inguinal nerve. Direct sonographic visualization of the inguinal nerve has been used in other studies to facilitate regional anesthesia, but to our knowledge, no studies have used this technique for localization of nerves for percutaneous lead placement for PNS. Methods. Each patient was chosen to undergo trial stimulation using percutaneously placed peripheral nerve stimulator leads. In these two cases, both patients presented with similar complaints of chronic groin pain consistent with ilioinguinal neuralgia. Both underwent multiple previous nerve blocks, all of which gave good but transient relief using traditional block techniques. Both patients were trialed on multiple medications, which either gave incomplete relief of pain or were limited by side-effects. Results. Both patients had relatively easy localization of ilioinguinal nerves affected using ultrasound and were provided with stimulating paresthesias which covered their normal pain. Discussion. The successful use of ultrasound as described in these two cases suggests an important role for ultrasound in localization of targeted nerves in percutaneous trial stimulation of injured peripheral nerve. The use of ultrasound may also play a role in permanent lead placement as well. Conclusion. More studies are needed to further qualify the role of ultrasound in isolating peripheral nerves, but the success of trial stimulation in these two cases holds promise for continued advancements in the field of neuromodulation.

Chronic pain in the cancer survivor: a new frontier.

OBJECTIVE: This monograph is intended to clarify the clinical problem of chronic pain in cancer patients. DESIGN: A pertinent literature review on chronic pain syndromes in cancer patients was undertaken using Medline. Further, the treatment strategies for cancer versus chronic pain are contrasted and clarified. RESULTS: With increasing cancer survivorship come new challenges in patient care. In the United States, the cancer-related death rate has dropped by 1.1% per year from 1993-2002. Seventy-five percent of children and two out of three adults will survive cancer, whereas 50 years ago just one out of four survived. The net effect of these trends and opportunities is a large and rapidly growing population of persons living longer with cancer and/or as cancer survivors. While agreement exists on the best strategies for assessment and treatment of most acute cancer pain syndromes, little consensus exists on the treatment of chronic pain in the patient with slowly progressive cancer or the cancer survivor. CONCLUSIONS: The landscape of "cancer pain" is shifting quickly into a chronic pain situation in many instances, thereby blurring previous lines of distinction in treatment strategies most suited for "chronic" versus "malignant" pain. Adopting chronic pain treatment strategies including pharmacologic and other pain control techniques, rehabilitation care, and psychological coping strategies may lead to optimal outcomes. Lastly, as cancer evolves into a chronic illness, with co-morbid conditions, recurrent cancer, and treatment toxicities from repeated antineoplastic therapies, pain management challenges in the oncologic patient continue to increase in complexity.

Opioids for chronic noncancer pain. Tailoring therapy to fit the patient and the pain.

Opioids are powerful medications with a history that includes use for pain relief and, at times, addiction. This history of therapy versus drug abuse continues to cloud their prescription today, despite reports of effective treatment for the chronic pain that certain diseases can bring. Here, Drs Antoin and Beasley review the use of opioid agents in medicine, highlight the importance of proper patient selection and education in their use, and convey how opioids can be a viable option today for successful therapy for chronic noncancer pain.

Self efficacy as a mediator of the relationship between pain intensity, disability and depression in chronic pain patients.

To clarify the relationships between physical, and psychosocial components of chronic pain, a path analytic model was tested conceptualizing self efficacy as a mediator of disability. In turn, disability was hypothesized to mediate depression. This model could help explain the circumstances under which disability develops and why so many chronic pain patients become depressed. Questionnaires from 126 chronic pain patients (without prior depression) were reviewed from three pain clinics. Hypothesized and alternate models were tested using separate regression equations to identified models which best fit these data. Regression analysis supported that self efficacy partially mediates the relationship between pain intensity and disability. This model accounted for 47% of the explained variance in disability (P < 0.001). Six additional variables that were significantly related to disability in preliminary analysis, added to the explained variance in disability (R2 = 0.56), with gender and pain location paths remaining significant. In separate regression analyses, disability was found to partially mediate the relationship between pain intensity and depression (b = 0.47-0.33). This model accounted for 26% of the explained variance in depression. The addition of self efficacy to this model supported it as a stronger mediator (R2 = 0.32), and suggested that support for disability as a mediator of depression was a spurious finding. Both pain intensity and self efficacy contribute to the development of disability and depression in patients with chronic pain. Therefore, the lack of belief in ones own ability to manage pain, cope and function despite persistent pain, is a significant predictor of the extent to which individuals with chronic pain become disabled and/or depressed. Nevertheless, these mediators did not eliminate the strong impact that high pain intensity has on disability and depression. Therefore, therapy should target multiple goals, including: pain reduction, functional improvement and the enhancement of self efficacy beliefs.