Cranial Neuralgias.

Advances in diagnostic modalities have improved the understanding of the pathophysiology of neuropathic pain involving head and face. Recent updates in nomenclature of cranial neuralgias and facial pain have rationalized accurate diagnosis. Clear diagnosis and localization of pain generators are paramount, leading to better use of medical and targeted surgical treatments.

Detailed analysis of allergic cutaneous reactions to spinal cord stimulator devices.

The use of spinal cord stimulation (SCS) devices to treat chronic, refractory neuropathic pain continues to expand in application. While device-related complications have been well described, inflammatory reactions to the components of these devices remain underreported. In contrast, hypersensitivity reactions associated with other implanted therapies, such as endovascular and cardiac rhythm devices, have been detailed. The purpose of this case series is to describe the clinical presentation and course of inflammatory reactions as well as the histology of these reactions. All patients required removal of the entire device after developing inflammatory reactions over a time course of 1-3 months. Two patients developed a foreign body reaction in the lead insertion wound as well as at the implantable pulse generator site, with histology positive for giant cells. One patient developed an inflammatory dermatitis on the flank and abdomen that resolved with topical hydrocortisone. "In vivo" testing with a lead extension fragment placed in the buttock resulted in a negative reaction followed by successful reimplantation of an SCS device. Inflammatory reactions to SCS devices can manifest as contact dermatitis, granuloma formation, or foreign body reactions with giant cell formation. Tissue diagnosis is essential, and is helpful to differentiate an inflammatory reaction from infection. The role of skin patch testing for 96 hours may not be suited to detect inflammatory giant cell reactions that manifest several weeks post implantation.

Incidence and root cause analysis of wrong-site pain management procedures: a multicenter study.

BACKGROUND: Medical errors exact an inordinate toll on healthcare costs. One of the most publicized and analyzed type of medical error is wrong-site surgery. Yet, despite the burgeoning number of procedures performed, no literature exists on wrong-site pain management injections. The purpose of this study was to estimate the relative incidence and determine the causes of wrong-site pain management procedures. METHODS: Quality improvement records were examined during a 2-yr period from four civilian academic teaching hospitals, three military treatment facilities, and three private practices, for "sentinel" events involving wrong-site pain management procedures. A total of 13 cases (incidence 0.027%; 95% CI 0.01-0.05%) were identified from approximately 48,941 collective procedures of which 52.4% were deemed to be "at risk" for the occurrence. Root cause analyses were then conducted to determine the origin of each error. RESULTS: The 13 cases included five wrong-side transforaminal epidural steroid injections, six other wrong-side injections, and two wrong-level minimally invasive surgical procedures. In only one case was the "universal protocol" completely followed, and in nine procedures, multiple lapses occurred in protocol. Three patients had bilateral pathology, and in seven cases, the patient knew at the time that the wrong side was being injected. In no instance did any technical, legal, or professional consequences ensue from the error. CONCLUSIONS: Wrong-site nerve blocks occur more frequently in pain management centers than has previously been acknowledged. Adaptation of the universal protocol to nerve blocks and strict adherence to widely accepted guidelines may prevent wrong-site interventional pain procedures.

Low and therapeutic doses of antidepressants are associated with similar response in the context of multimodal treatment of pain.

BACKGROUND: Antidepressants are prescribed in a wide range of doses to treat both depression and chronic pain, with optimal psychopharmacology individualized for each patient. In the past decade more antidepressants from different chemical classes have become available and are being used for the treatment of both chronic pain and depression. OBJECTIVE: To review the utilization pattern changes and compare response rates of different classes and doses of antidepressants for various pain conditions in the context of multimodal therapies. DESIGN: Chart review. METHODS: We reviewed 5,916 records at an outpatient multidisciplinary pain center. Of these, 379 records were for patients diagnosed with cancer pain. Because the mechanisms and treatment approaches to cancer pain can differ greatly from non-cancer chronic pain, these records were excluded from the analysis. We assessed 1,506 medical records for patients with chronic non-caner pain who had used at least one antidepressant, with the main outcome measure being the Numeric Rating Pain Scale, 0-10. RESULTS: Of the 5,916 charts reviewed, 1,506 (25.4%) chronic non-cancer pain charts recorded the prescription of at least one antidepressant. Most patients received a combination of medications and procedures. Of the 450 patients receiving secondary amines, favorable responses were recorded for 340 (76%) patients, while 103 (23%) did not respond and 7 had unknown responses. Of the 492 patients receiving tertiary amines, favorable responses were recorded for 375 (76%) patients, while 113 (23%) did not respond, and 4 had unknown responses. Of the 533 patients receiving SSRI/SNRIs, favorable responses were recorded for 382 (72%) patients, while 147 (28%) did not respond, and 4 had unknown responses. Of the 369 patients receiving atypical antidepressants, favorable responses were recorded for 272 (74%) patients, while 94 (25%) did not respond, and 3 had unknown responses. LIMITATIONS: A retrospective study design and the use of antidepressants as a part of multimodal treatment of pain. CONCLUSION: The data suggest that in the context of multimodal treatment for chronic pain, antidepressant therapy at both low and therapeutic doses demonstrates similar response rates. Tricyclic antidepressants (TCAs), which include secondary and tertiary amines, as well as SSRI/SNRIs and atypicals, all appear to show similar favorable response rates.

The use of opioids in the treatment of osteoarthritis: when, why, and how?

As life expectancy increases every decade, the incidence and prevalence of osteoarthritis (OA) also will increase. Despite progress in our knowledge of the pathophysiology of OA, the management of OA-mediated pain continues to challenge physicians. Concern regarding the cardiovascular effects of cyclooxygenase-2 inhibitors and the gastrointestinal and renal side effects of nonsteroidal anti-inflammatory drugs (NSAIDs) in general has limited the use of these medications in the management of chronic non-cancer pain. Appropriately dosed and monitored use of opioids for OA pain, when more conservative methods have failed, has potentially fewer life-threatening complications associated with it than the more commonly and often less successfully employed pharmacotherapeutic approaches to care. When used as part of a multimodal approach to pain control, opioids are a safe and effective treatment for joint pain, including that of OA. Patients for whom NSAIDs are contraindicated, or for whom combined acetaminophen, tramadol, and NSAID therapy is ineffective, may be started on low-dose opioids and titrated as needed and tolerated. Patient education and informed consent, exercise, complementary medicine, and the use of a controlled substance agreement increases the likelihood of patient compliance with treatment guidelines, improving functional capacity and quality of life.

What is mechanical back pain and how best to treat it?

Back pain is one of the most common patient complaints brought forth to physicians. Mechanical back pain accounts for 97% of cases, arising from spinal structures such as bone, ligaments, discs, joints, nerves, and meninges. Acute back pain in the absence of progressive neurologic deficits and other underlying nonmechanical causes may be treated conservatively, with specific emphasis on maintaining activity levels and function. Mechanical back pain persisting for more than 4 to 6 weeks may warrant further diagnostic testing and imaging. Common causes of mechanical back pain include spinal stenosis, herniated discs, zygapophysial joint pain, discogenic pain, vertebral fractures, sacroiliac joint pain, and myofascial pain. A wide variety of treatments are available, with different treatments specifically targeted toward different causes. A balanced approach, which takes into account patient psychosocial factors and incorporates multidisciplinary care, increases the likelihood of success from back pain interventions.

Factors predicting success and failure for cervical facet radiofrequency denervation: a multi-center analysis.

BACKGROUND AND OBJECTIVES: The concept of radiofrequency denervation has recently come under question in light of several studies showing minimal to no benefit. One possibility proposed for these negative outcomes is poor selection criteria. Unlike virtually all other spine interventions, the factors associated with success and failure for cervical facet denervation have yet to be determined. The purpose of this study is to determine which demographic, clinical and treatment factors are associated with cervical facet radiofrequency denervation outcomes. METHODS: Data were garnered from 3 academic medical centers on 92 patients with chronic neck pain who underwent radiofrequency denervation after a positive response to diagnostic local anesthetic blocks. Success was defined as at least 50% pain relief lasting at least 6 months. Variables evaluated for their association with outcome included age, sex, duration of pain, opioid use, pain referral pattern, paraspinal tenderness, pain exacerbated by extension/rotation, magnetic resonance image abnormalities, diabetes, smoking, scoliosis, obesity, prior surgery, and levels treated. RESULTS: The only clinical variable associated with success was paraspinal tenderness. Factors associated with treatment failure included radiation to the head, opioid use, and pain exacerbated by neck extension and/or rotation. CONCLUSIONS: Selecting patients based on key clinical variables may increase the chance of treatment success for cervical facet radiofrequency denervation.

The use of opioids in the treatment of osteoarthritis: when, why, and how?

As life expectancy increases every decade, the incidence and prevalence of osteoarthritis (OA) also will increase. Despite progress in our knowledge of the pathophysiology of OA, the management of OA-mediated pain continues to challenge physicians. Concern regarding the cardiovascular effects of cyclooxygenase-2 inhibitors and the gastrointestinal and renal side effects of nonsteroidal anti-inflammatory drugs (NSAIDs) in general has limited the use of these medications in the management of chronic non-cancer pain. Appropriately dosed and monitored use of opioids for OA pain, when more conservative methods have failed, has potentially fewer life-threatening complications associated with it than the more commonly and often less successfully employed pharmacotherapeutic approaches to care. When used as part of a multimodal approach to pain control, opioids are a safe and effective treatment for joint pain, including that of OA. Patients for whom NSAIDs are contraindicated, or for whom combined acetaminophen, tramadol, and NSAID therapy is ineffective, may be started on low-dose opioids and titrated as needed and tolerated. Patient education and informed consent, exercise, complementary medicine, and the use of a controlled substance agreement increases the likelihood of patient compliance with treatment guidelines, improving functional capacity and quality of life.

Fundamentals of interventional pain medicine.

Chronic pain is one of the most common and challenging medical problems facing our society. The specialty of pain medicine has grown steadily in recent years, largely because of the recognition that multiple factors contribute to chronic pain. The practice of pain medicine is multidisciplinary in approach, incorporating modalities from various specialties to ensure the comprehensive evaluation and treatment of the pain patient. The integration of various specialties such as anesthesiology, neurology, neurologic surgery, orthopedic surgery, physical medicine, and psychiatry is essential to treating patients with chronic pain and to establishing continuity of care. Research in the last 30 years has developed a variety of alternatives or adjuncts to opiates for chronic pain, including neuroactive medications, counterstimulation methods, and cognitive-behavioral therapies. Pain medicine specialists have provided leadership in the development of the practice, with the application of a wide verity of central and peripheral nerve blocks, sympathetic and neurolytic blocks, intradiscal procedures, neuromodulation techniques, intrathecal infusion systems, and other technical procedures that are firmly linked to a biomedical model of pain.

A clinical trial demonstrates the analgesic activity of intravenous parecoxib sodium compared with ketorolac or morphine after gynecologic surgery with laparotomy.

OBJECTIVE: The purpose of this study was to compare the analgesic activity of 2 doses of parecoxib sodium, ketorolac, and morphine with placebo after gynecologic surgery that requires laparotomy. STUDY DESIGN: In a randomized, controlled, double-blind, parallel-group study, 208 patients, after surgical hysterectomy, received single-dose intravenous placebo, parecoxib sodium 20 mg or 40 mg, ketorolac 30 mg, or morphine 4 mg followed by multiple-dose parecoxib sodium or ketorolac as needed. Primary efficacy variables were time to onset of analgesia, pain intensity differences, pain relief, time to first rescue/remedication, and global evaluation of study medication. RESULTS: Single-dose parecoxib sodium 40 mg provided significantly better pain responses to placebo or morphine 4 mg and was comparable to ketorolac 30 mg. Multiple-dose parecoxib sodium 20 mg, 4 times daily, or 40 mg, twice daily, was comparable to ketorolac 30 mg, 4 times daily. Parecoxib sodium was well tolerated. CONCLUSION: Parecoxib sodium is an effective analgesic in the management of acute postoperative pain after laparotomy surgery.

Epidural clonidine relieves intractable neuropathic itch associated with herpes zoster-related pain.

OBJECTIVE: We present a case of intense herpes zoster-related pain and itching in the ophthalmic division of the trigeminal nerve (V1). Successful pain and itch management was achieved after insertion of a high thoracic epidural catheter with a continuous infusion of bupivacaine and clonidine. CASE REPORT: A 73-year-old woman with metastatic malignant melanoma developed acute herpes zoster-related pain and itching unresponsive to conventional oral medications. The patient described severe and frequent attacks of lancinating pain occurring in the dermatomal distribution of the left ophthalmic division of the trigeminal nerve. She also had a disturbing itch in the same distribution as her pain. The patient had significant reduction in the frequency and intensity of the lancinating attacks after placement of a thoracic epidural catheter with continuous infusion of 1 microg/mL clonidine and 0.05% bupivacaine. The itching resolved completely as well. CONCLUSION: High thoracic epidural infusion of bupivacaine and clonidine was beneficial in relieving neuropathic itch in a patient with acute herpes zoster-related pain in the distribution of the trigeminal nerve.

Diagnosis and treatment of neuropathic pain.

Currently, no consensus on the optimal management of neuropathic pain exists and practices vary greatly worldwide. Possible explanations for this include difficulties in developing agreed diagnostic protocols and the coexistence of neuropathic, nociceptive and, occasionally, idiopathic pain in the same patient. Also, neuropathic pain has historically been classified according to its etiology (e.g., painful diabetic neuropathy, trigeminal neuralgia, spinal cord injury) without regard for the presumed mechanism(s) underlying the specific symptoms. A combined etiologic/mechanistic classification might improve neuropathic pain management. The treatment of neuropathic pain is largely empirical, often relying heavily on data from small, generally poorly-designed clinical trials or anecdotal evidence. Consequently, diverse treatments are used, including non-invasive drug therapies (antidepressants, antiepileptic drugs and membrane stabilizing drugs), invasive therapies (nerve blocks, ablative surgery), and alternative therapies (e.g., acupuncture). This article reviews the current and historical practices in the diagnosis and treatment of neuropathic pain, and focuses on the USA, Europe and Japan.

Percutaneous radiofrequency lesioning of sensory branches of the obturator and femoral nerves for the treatment of non-operable hip pain.

BACKGROUND: Chronic hip pain is often a debilitating problem and many patients are not good surgical candidates. Furthermore, hip replacement surgery has significant associated risks. We offer a conservative approach to hip replacement using radiofrequency lesioning. METHODS: This is a case series of 4 patients who had anterior and or medial hip pain who underwent percutaneous radiofrequency lesioning of the sensory branches of the obturator and femoral nerves. All of the patients had significant co-morbidities and the risks out weighed the benefits of surgery. All the patients had diagnostic blocks with local anesthetic to the sensory articular branches of the obturator and femoral nerves and showed temporary benefit. Continuous radiofrequency lesioning was performed from 60 degrees C to 80 degrees C for 90 seconds. The outcome measures were improvement in visual analogue scale (VAS), improvement in function and the decreased use of pain medications. RESULTS: All four patients had reduction in pain, while 3 of 4 patients had improved functioning. Two of the four patients had decreased use of their pain medication. One of the four patients reported numbness at the hip and there were no other side effects. CONCLUSION: Percutaneous radiofrequency lesioning of the sensory branches of the obturator and femoral nerves appears to be a safe alternative to hip replacement, especially in those patients where surgery is not an option. Further studies are needed to confirm our results.

Risk assessment of hemorrhagic complications associated with nonsteroidal antiinflammatory medications in ambulatory pain clinic patients undergoing epidural steroid injection.

UNLABELLED: We prospectively studied 1035 individuals undergoing 1214 epidural steroid injections to determine the risk of hemorrhagic complications. A history of bruising or bleeding was present in 176 (15%) patients. A platelet count was assessed in 77 patients before the epidural steroid injection; none was less than 100 x 10(9)/L. Nonsteroidal antiinflammatory drugs (NSAIDs) were reported by 383 (32%) patients, including 34 patients on multiple medications. Aspirin was the most common NSAID and was noted by 158 patients, including 104 patients on 325 mg or less per day. There were no spinal hematomas (major hemorrhagic complications). Blood was noted during needle or catheter placement in 63 (5.2%) patients (minor hemorrhagic complications). NSAIDs did not increase the frequency of minor hemorrhagic complications. However, increased age, needle gauge, needle approach, needle insertion at multiple interspaces, number of needle passes, volume of injectant, and accidental dural puncture were all significant risk factors for minor hemorrhagic complications. There were 42 patients with new neurologic symptoms or worsening of preexisting complaints that persisted more than 24 h after injection; median duration of the symptoms was 3 days (range, 1-20 days). Our results confirm those of previous studies performed in obstetric and surgical populations that document the safety of neuraxial techniques in patients receiving NSAIDs. We conclude that epidural steroid injection is safe in patients receiving aspirin-like antiplatelet medications. Minor worsening of neurologic function may occur after epidural steroid injection and must be differentiated from etiologies requiring intervention. IMPLICATIONS: Previous studies performed in obstetric and surgical populations have demonstrated that antiplatelet therapy does not increase the risk of spinal hematoma associated with spinal or epidural anesthesia and analgesia. We confirm the safety of epidural steroid injection in patients receiving aspirin-like medications.

Discitis associated with pregnancy and spinal anesthesia.

UNLABELLED: Discitis (inflammation of the intervertebral disk) most commonly develops as a rare complication of bacterial infection or chemical or mechanical irritation during spine surgery (1) with a postoperative incidence of 1%-2.8% (2). It is also a complication of discography-the intradiscal injection of saline or contrast material (3). The incidence of postdiscography discitis is 1%-4% (3); no cases have been reported when prophylactic antibiotics have been used, supporting the theory of bacterial contamination (3). Although it is controversial whether discitis can be caused by an aseptic or infectious process, recent data suggest that persistent discitis is almost always bacterial (4). Honan et al. (5) reported 16 cases of spontaneous discitis and reviewed another 52 patients from the literature. In their series, patients tended to have one or more comorbid conditions, such as diabetes, vertebral fracture, or a preexisting spine injury. Spontaneous discitis has also been associated with advanced age, IV drug abuse, IV access contamination, urinary tract infection, and immunocompromised states (5,6). No cases of infectious discitis associated with pregnancy and spinal anesthesia have been reported in the English literature. Discitis presents as spasmodic pain in the back that may be referred to the hips or groin (7). The pain may radiate to the lower extremities. The erythrocyte sedimentation rate is usually increased. Radiological changes in discitis include narrowing of the intervertebral disk space, vertebral sclerosis, and erosion of the end plates. The best diagnostic measure may be magnetic resonance imaging (MRI) or a combination of bone and gallium scanning (2). The mainstay for discitis treatment is pain control and antibiotics; surgical intervention is usually not required. Complications of discitis include intervertebral fusion, epidural abscess, and paralysis. IMPLICATIONS: This is a case report of a disk infection (discitis) caused by the bacteria, Streptococcus bovis after spinal anesthesia for cesarean delivery. S. bovis rarely causes discitis, and spinal anesthesia for labor and delivery has not been reported as a cause of discitis.