A Pre-clinical Study of the Response Threshold of Intact and Transected Nerves to Stimulation by Transcutaneous Intense Focused Ultrasound.

We used diagnostic ultrasound imaging to guide individual bursts (0.1 s) of 2 MHz intense focused ultrasound (iFU) to determine the sensitivity of intact and transected nerves. We found that all nerves had greater sensitivity to iFU stimulation than surrounding muscle. Intact nerves from healthy volunteers had less sensitivity to iFU stimulation (272 ± 35 W/cm2 [median ± standard error]) than transected nerves (19 ± 37 W/cm2). Intact, contralateral nerves of amputees dichotomized naturally into two groups-one very sensitive to iFU stimulation (6 ± 2 W/cm2) and one relatively insensitive (539 ± 19 W/cm2), compared with the intact nerves of healthy volunteers. Our study demonstrates the ability of iFU under ultrasound image guidance to stimulate deep, intact and transected peripheral nerves. It also highlights differences in the receptivity to ultrasound stimulation of the peripheral nerves of amputees versus healthy volunteers.

The beta-adrenergic receptor agonist, terbutaline, reduces UVB-induced mechanical sensitization in humans.

OBJECTIVES: Previously, we found in cultures of primary neurons and in animals that sensitized primary neurons can be desensitized by treatment with e.g. beta-adrenergic receptor agonists. We now tested whether also in human sensitization such as UVB-radiation induced sunburn-like hyperalgesia can be reduced by intradermal injection of the beta-adrenergic receptor agonist terbutaline. METHODS: In our prospective randomized study, 17 participants received an individual UVB dose to cause a defined local sunburn-like erythema at four locations, two on each forearm. Twenty-four hours later, the sensitized four areas were injected intradermally with terbutaline pH 4.3, terbutaline pH 7.0, saline pH 4.3 or saline pH 7.0, respectively. Pain thresholds were examined before and after induction of UVB-sensitization, and 15, 30 and 60 min after injection of the respective solution. Mechanical pain thresholds of the skin and of deeper tissues were determined by pinprick and pressure algometer measurements, respectively. RESULTS: UVB-irradiation decreased mechanical pain thresholds for pinprick and pressure algometer measurements demonstrating a successful sunburn-like sensitization. Intradermal injection of terbutaline pH 7.0 into the sensitized skin reduced the sensitization for all measured timepoints as determined by pinprick measurements. Pinprick measurements of sensitization were not reduced by injection of terbutaline pH 4.3, saline solution pH 7.0 or saline solution pH 4.3. Also, sensitization of deeper tissue nociceptors were not altered by any of the injections as measured with the pressure algometer. CONCLUSIONS: Similar to our cellular observations, also in humans beta-adrenergic agonists such as terbutaline can reduce the sensitization of primary neurons in the skin. SIGNIFICANCE: We previously showed in model systems that beta-adrenergic stimulation can not only sensitize but also desensitize nociceptors. Our study shows that also in humans beta-adrenergic agonists desensitize if injected into UVB-sensitized skin. This indicates an analgesic activity of adrenergic agonists in addition to their vasoconstrictory function.

[Chili for therapy of trigeminus neuralgia: a case report]. / Chili zur Therapie der Trigeminusneuralgie : Ein Fallbericht.

We report the case of a 39-year-old female patient who suffered from trigeminal neuralgia of the left lingual nerve for 6 years. The previous therapy according to the guidelines including a Jannetta operation was unsuccessful. Only after beginning with daily mastication and consumption of very hot chilli peppers has the patient become reliably pain-free.

Haemophilus influenzae and Streptococcus pneumoniae infections in children with cerebrospinal fluid shunts.

OBJECTIVE: This paper reviews the frequency of central nervous system infections due to Haemophilus influenzae and Streptococcus pneumoniae associated with cerebrospinal fluid (CSF) shunts in pediatric patients. The need for immunizations in this patient population is also evaluated. PATIENTS: All patients with cerebrospinal fluid shunts except those with brain tumors seen in our clinics. METHODS: We reviewed data in three computer databases, kept prospectively recording details of CSF shunt procedures and CSF shunt-related infections. RESULTS: 1,226 patients underwent 3,889 shunt placements between 1957 and 2007. Twelve patients had 14 episodes of Haemophilus or pneumococcal infections. CONCLUSIONS: Children with CSF shunts are at high risk for infection with H. influenzae and S. pneumoniae. Routine immunizations during infancy in addition to the 23-valent polysaccharide pneumococcal vaccine should be highly and actively encouraged by health care providers caring for children with CSF shunts. Additional expanded-coverage vaccines should be utilized if and when they become available.

Pain intensity, pain interference and characteristics of spinal cord injury.

STUDY DESIGN: Postal survey. OBJECTIVES: To examine if the intensity of pain in persons with spinal cord injury (SCI) varied as a function of pain site, and to identify the patient and SCI characteristics associated with pain location, pain intensity and pain interference in a sample of persons with SCI. SETTING: Community sample, United States. METHODS: A postal survey including measures of pain intensity, pain interference, other pain, demographic and medical characteristics was completed by 238 adults with SCI. RESULTS: Average pain intensity was moderate and pain was common across the body. Demographic and medical variables, including SCI level, were generally not associated with pain prevalence, intensity and interference. However, persons with higher level injuries were more likely to report upper extremity pain than persons with paraplegic injuries. The lower body was the location of the highest pain ratings. CONCLUSION: Persons with SCI tend to experience high pain intensity over multiple body locations. Lower body pain was as common as upper extremity pain, but tended to be more intense.

Can evidence change the rate of back surgery? A randomized trial of community-based education.

CONTEXT: Timely adoption of clinical practice guidelines is more likely to happen when the guidelines are used in combination with adjuvant educational strategies that address social as well as rational influences. OBJECTIVE: To implement the conservative, evidence-based approach to low-back pain recommended in national guidelines, with the anticipated effect of reducing population-based rates of surgery. DESIGN: A randomized, controlled trial. SETTING: Ten communities in western Washington State with annual rates of back surgery above the 1990 national average (158 operations per 100,000 adults). PARTICIPANTS: Spine surgeons, primary care physicians, patients who were surgical candidates, and hospital administrators. INTERVENTION: The five communities randomized to the intervention group received a package of six educational activities tailored to local needs by community planning groups. Surgeon study groups, primary care continuing medical education conferences, administrative consensus processes, videodisc-aided patient decision making, surgical outcomes management, and generalist academic detailing were serially implemented over a 30-month intervention period. OUTCOME MEASURE: Quarterly observations of surgical rates. RESULTS: After implementation of the intervention, surgery rates declined in the intervention communities but increased slightly in the control communities. The net effect of the intervention is estimated to be a decline of 20.9 operations per 100,000, a relative reduction of 8.9% (P = 0.01). CONCLUSION: We were able to use scientific evidence to engender voluntary change in back pain practice patterns across entire communities.

The future of pain management in managed care.

Pain management has made great strides in clinical practice and education, and in research documenting its effectiveness on pain relief, functional improvement, and cost. The profile of pain in managed care settings has recently been raised, notably because of the trend toward replacing inexpensive generic drugs with new and expensive drugs for pain treatment. Managed care organizations have greater motivation to focus on pain care because of recent regulatory initiatives, new accreditation standards, and legal precedents. In order for pain programs to improve the quality of pain care in MCOs, they must balance the complex needs of patients with pain with the financial constraints of the managed care setting.

Pain following spinal cord injury.

Chronic pain is an important problem following spinal cord injury (SCI) and is a major impediment to effective rehabilitation. The reported prevalence of chronic SCI pain is variable but averages 65% with around one third of these people rating their pain as severe. The mechanisms responsible for the presence of pain are poorly understood. However, evidence from clinical observations and the use of animal models of SCI pain suggests that a number of processes may be important. These include functional and structural plastic changes in the central nervous system following injury, with changes in receptor function and loss of normal inhibition resulting in an increased neuronal excitability. A number of specific types of SCI pain can be distinguished based on descriptors, location and response to treatment. Nociceptive pain can arise from musculoskeletal structures and viscera and neuropathic pain can arise from spinal cord and nerve damage. The role of psychological and environmental factors also needs to be considered. Accurate identification of these pain types will help in selecting appropriate treatment approaches. Current treatments employ a variety of pharmacological, surgical, physical and psychological approaches. However, evidence for many of the treatments in use is still limited. It is hoped that future research will identify effective treatment strategies that accurately target specific mechanisms.

Tic douloureux.

Tic douloureux is an excruciatingly painful condition that primarily affects elderly people. It consists of unilateral electric shock-like facial pains triggered by non-noxious stimulation with clear-cut pain-free intervals. It should be discriminated from all other types of facial pain by the history and physical examination. Primary treatment includes anticonvulsant drugs; if these fail or side effects prevent their use, a surgical procedure is warranted. Almost every patient with tic douloureux can be relieved of his or her pain with anticonvulsant medications or surgery. Stereotactic radiosurgery, percutaneous gangliolysis and suboccipital craniectomy with microvascular decompression are the primary surgical options. The common aspects of tic douloureux and some of the rarer variations are reviewed, and treatment options are presented.

Pain and suffering.

It is suffering, not pain, that brings patients into doctor's offices in hopes of finding relief. Astounding developments in our understanding of the mechanisms of nociception should not cause us to lose sight of our patients' goals. Chronic pain is far more than a sensory process. We must maintain the biopsychosocial model of chronic pain if we are to provide effective health care to our patients. Understanding the components of pain facilitates this goal. Suffering is an emergent property of the human brain and is dependent upon consciousness. It too is worthy of study by scientists and of concern to clinicians.

Intrathecal baclofen for the treatment of intractable spasticity of spine or brain etiology.

Objective. To determine the long-term relief of spasticity and complication rates in patients who underwent placement of a programmable intrathecal baclofen pump for treatment of medically intractable spasticity of spine or brain etiology. Methods. Sixty-two consecutive adult patients who underwent placement of a programmable pump were retrospectively reviewed. Results. Spasticity was clinically and statistically significantly decreased in all patients. Catheter-related kinks, breaks, dislodgments, and disconnections were the most common complications followed by drug-related effects, infections, and wound complications. Conclusions. Intrathecal baclofen is a very effective strategy for the relief of medically intractable spasticity of spine or brain etiology. Even though 36% of patients have required revisions, no patient has experienced any long-term morbidity. Patients and their primary care givers have been pleased with the long-term effects of this therapy upon quality of life.

Economic implications of pain management.

BACKGROUND: Economic issues in pain management affect the patient, the provider and society. This paper will review some of the data on the costs to society of chronic pain and its associated disability. It will also look at the costs to patient and provider of alternative economic models. Conceptual issues that underlie health care delivery and the attendant costs must be addressed if society is to gain control over runaway health care costs and reduce the economic burden of chronic pain and disability for the patient as well as the provider. METHODS: Literature review and synthesis. RESULTS: Chronic pain is the primary cause of health care consumption and disability in the working years. Multidisciplinary pain clinics have proven utility. Data on efficacy of most other kinds of care is lacking. Disability costs are related to conceptual inadequacies and the medicalization of post-industrial societies. CONCLUSION: To control inappropriate care and escalating costs, we must change concepts of pain and disability and the methods of funding both of these in relation to chronic pain. The outcome of the continuing struggle between the profession of medicine, the state and capitalists will determine how and whether pain management is a part of medical care.

Pain: an overview.

Until the 1960s, pain was considered an inevitable sensory response to tissue damage. There was little room for the affective dimension of this ubiquitous experience, and none whatsoever for the effects of genetic differences, past experience, anxiety, or expectation. In recent years, great advances have been made in our understanding of the mechanisms that underlie pain and in the treatment of people who complain of pain. The roles of factors outside the patient's body have also been clarified. Pain is probably the most common symptomatic reason to seek medical consultation. All of us have headaches, burns, cuts, and other pains at some time during childhood and adult life. Individuals who undergo surgery are almost certain to have postoperative pain. Ageing is also associated with an increased likelihood of chronic pain. Health-care expenditures for chronic pain are enormous, rivalled only by the costs of wage replacement and welfare programmes for those who do not work because of pain. Despite improved knowledge of underlying mechanisms and better treatments, many people who have chronic pain receive inadequate care.

Resolution of central pain after embolization of an arteriovenous malformation. Case report.

The authors describe a patient with right-sided central pain resulting from a left parietal arteriovenous malformation (AVM). The AVM was treated with staged embolization and stereotactic radiosurgery, and its obliteration was documented on follow-up angiographic studies. Surprisingly, the patient noted complete resolution of her pain syndrome after embolization, which is an extremely rare result. Central pain and its proposed mechanisms are discussed.

19-year follow-up of fetal myelomeningocele brought to term.

We conducted a 19-year follow-up study of 223 infants with myelomeningocele born by cephalic presentation, 68 born by pre-rupture of amniotic membranes cesarean section (PRAM C/S) and 155 born vaginally to determine outcome. We recorded radiographic level as the last intact vertebral arch at the cephalad end of the spinal defect from standard AP films of the spine. Protrusions of the lesions dorsal to the back were obtained from medical records or parental recall. Subsequent spinal cord abnormalities (hydromyelia, tethered cord and hypoplasia) were determined by patient's symptoms and verified by MRI. Data were from our Patient Data Management System and analyzed using Microsoft Excel and Epi Info 6. Flat lesions protruding less than 1.0 cm beyond the plane of the back and those associated with breech position or kyphus were not benefited by PRAM CIS (Fisher's Exact, p = 0.58 between the two types of delivery for motor level). Flat lesions were more common in the vaginally delivered group (p = 0.01). Lesions protruding equal to 1.0 cm or beyond were associated with less paralysis after PRAM C/S (p = 0.01). Although tethered cord syndrome was more common in the PRAM C/S group (p = 0.02), there was no difference in the muscle strength loss between the PRAM C/S and the vaginally delivered groups. Symptomatic hydromyelia was equally distributed but spinal cord hypoplasia was more common in the PRAM C/S group (p = 0.03). Due to the limited numbers of patients in each group available for analysis, we recommend further study to ascertain the appropriate management of fetal myelomeningocele diagnosed in utero and brought to term.