Andrea M. Trescot

Percutaneous lysis of epidural adhesions--evidence for safety and efficacy.

Background:  Percutaneous lysis of epidural adhesions is done worldwide. Over 1.7 million of these procedures were done in the U.S.A. by 2006. This interventional pain management technique is used to treat chronic low back pain (LBP) and/or radiculopathy. The primary object of the approach is to target drug delivery to areas of pathology in the spinal epidural space. The procedure involves removing barriers, such as epidural fibrosis, that prevent drug from reaching target sites.

Treatment of phantom limb pain by cryoneurolysis of the amputated nerve

The pathophysiology of phantom limb pain (PLP) is multifactorial. It probably starts in the periphery and is amplified and modified in the central nervous system. A small group of patients with PLP were questioned as to the portion of the phantom limb affected by pain (eg, “great toe,” “thumb”). In the stump, the corresponding amputated nerve was located with a nerve stimulator. With correct placement and stimulation, the PLP could then be reproduced or exacerbated. A small dose of local anesthesia was then injected, resulting in the disappearance of the PLP. If a peripheral nerve injection gave temporary relief, our final treatment was cryoanalgesia at this location. Evaluation of 5 patients, followed for at least 2.5 years, yielded the following results: 3 patients had excellent results (100%, 95%, and 90% decrease in complaints, respectively), 1 patient had an acceptable result (40% decrease), and 1 patient had only a 20% decrease in pain. Although both central and peripheral components are likely involved in PLP, treatment of a peripheral pain locus with cryoanalgesia should be considered. We propose the identification of a peripheral etiology may help match patients to an appropriate therapy, and cryoanalgesia may result in long‐term relief of PLP.

Extended-release hydrocodone - gift or curse?

Hydrocodone is a semisynthetic opioid, which has been used for decades as a short-acting analgesic combined with acetaminophen (or less commonly ibuprofen). Several long-acting, non-acetaminophen-containing hydrocodone formulations are undergoing trials in the US under the auspices of the US Food and Drug Administration, and may be available shortly. This article reviews some of the advantages (including drug familiarity and lack of acetaminophen toxicity) and potential disadvantages (including altered use patterns and high morphine equivalent dosing) of such a medication formulation. We also discuss the abuse potential of long-acting versus short-acting opioids in general and hydrocodone specifically, as well as the metabolism of hydrocodone.

Epidemiology and Pathophysiology

Peripheral nerve entrapments are common and treatable sources of pain. These conditions are a significant cause of morbidity and disability in the general population. The epidemiology and pathophysiology of peripheral nerve entrapment are reviewed, highlighting the most important risk factors and mechanisms leading to peripheral nerve entrapment.

Distal Saphenous Nerve Entrapment

Entrapment of the distal saphenous nerve is the least common of the entrapment syndromes in the ankle and foot. However, the nerve can be injured by inappropriate footwear or as a complication of a variety of procedures.

Pain Management Techniques and Practice: New Approaches, Modifications of Techniques, and Future Directions

The practice of pain medicine has radically changed over the last twenty years, morphing from an almost exclusively anesthesia-based, recovery room, and procedure-oriented part-time practice into a multidisciplinary, multimodality, multispecialty field. These changes have been the consequence and the stimuli for the expansion of new medications and techniques, which have improved the diagnosis and treatment of painful conditions. This issue attempts to highlight some of the advances in anesthesiology and pain, including epidural analgesia, spinal cord stimulation, and trigger point diagnosis and treatment. There is also a case report of a technique utilizing transforaminal blood patches to treat intracranial hypotension, analogous to postdural puncture headaches. Particularly intriguing, given the current controversy regarding the role of opioids in the management of chronic pain, is the report of the lasting developmental delays seen in infant rats exposed to fentanyl. This observation could have a significant impact on the decision to initiate opioids in human infants and children and adds data to the current dilemma. Pain medicine is a rapidly growing field, and the innovations described in this issue move the field further into the future. Hopefully, the reader will be encouraged to utilize and expand on these topics in their own practice. Andrea Trescot Hans Hansen Standiford Helm Giustino Varras Magdi Iskander

Tibial Nerve Entrapment

The posterior tibial nerve is a portion of the sciatic nerve that runs down the posterior leg into the foot. It can be entrapped at two major sites: behind the knee at the proximal edge of the soleus muscle and at the ankle in the tarsal tunnel. The small terminal branches of the tibial nerve can be entrapped in the distal ankle and foot and are discussed in other chapters. Posterior tibial nerve entrapment can lead to pain and dysesthesias in the calf and sole of the foot, as well as dysfunction of the foot flexors and intrinsic muscles.

Posterior Femoral Cutaneous Nerve Entrapment: Pelvic

The posterior femoral cutaneous nerve is an under-recognized cause of posterior thigh and perineal pain. There are many overlapping pain patterns in this region, and the etiology of posterior femoral cutaneous entrapment must be actively sought out to be diagnosed.

Posterior Femoral Cutaneous Nerve Entrapment: Low Back

The posterior femoral cutaneous nerve is an under-recognized cause of posterior thigh and buttocks pain. There are many overlapping pain patterns in this region, and the etiology of posterior femoral cutaneous nerve entrapment must be actively sought out in order to be diagnosed.

Neuromodulation for Treatment of Nerve Entrapment Syndromes

The neurosurgical management of nerve entrapment syndromes, beyond the options of decompression, transfer, and grafting, also includes the modality of neuromodulation. Neuromodulation techniques involve interrupting signals from entrapped nerves anywhere along the signal’s pathway, from just proximal to the nerve lesion up to the central nervous system.