Relationship between pain sensitivity and resting arterial blood pressure in patients with painful temporomandibular disorders

OBJECTIVE: Patients experiencing temporomandibular disorders (TMD) show greater sensitivity to painful stimuli than age- and gender-matched control subjects. This enhanced pain sensitivity may result, at least in part, from an alteration in pain regulatory systems that are influenced by resting arterial blood pressure. In this study, we examined the relationship between resting systolic blood pressure and pain perception in 64 female TMD and 23 age-matched pain-free female subjects. METHOD: Resting arterial blood pressure and measures of thermal and ischemic pain threshold and tolerance were determined for each participant. Subjective ratings of thermal pain evoked by suprathreshold noxious thermal stimuli (45-49 degrees C) using a magnitude matching procedure were also obtained for both groups. RESULTS: TMD patients had lower thermal and ischemic pain thresholds and tolerances than pain-free subjects (ps < .05). Both groups provided equivalent intensity ratings to suprathreshold noxious thermal stimuli. A median split of each group based on resting systolic blood pressure revealed an influence of blood pressure on both thermal and ischemic pain perception for the Pain-Free group. The Pain-Free high resting blood pressure subgroup had higher thermal pain tolerances, higher ischemic pain thresholds, and provided lower magnitude estimates of the intensity of graded heat pulses compared with the Pain-Free low blood pressure subgroup. A trend toward a significant effect of blood pressure level on ischemic pain tolerance was also observed for the Pain-Free group. In contrast to the Pain-Free group, blood pressure level did not influence ischemic or thermal pain perception for TMD patients. Similar to the lack of effect of resting blood pressure on experimental pain perception in TMD patients, resting blood pressure was not related to measures of clinical orofacial pain in TMD patients. CONCLUSIONS: These findings confirm our previous findings that TMD patients are more sensitive to noxious stimuli and suggest that painful TMD may result, at least in part, from an impairment in central pain regulatory systems that are influenced by resting arterial blood pressure.     

Somatic or sympathetic block for reflex sympathetic dystrophy. Which is indicated?

Patients with reflex sympathetic dystrophy (complex regional pain syndromes) are often referred to pain medicine physicians for assistance in providing pain control during rehabilitation of their painful upper extremity. When deciding which pain control technique to use in an individual patient, physicians must consider both somatic and sympathetic blocks. Each of these nerve blocks has advantages and disadvantages that may be tailored to an individual patient's pain state and rehabilitation program to optimize recovery.     

Epidural spinal cord stimulation for treatment of chronic pain--some predictors of success. A 15-year experience

BACKGROUND: We have used epidural spinal cord stimulation (SCS) for pain control for the past 15 years. An analysis of our series of 235 patients has clarified the value of specific prognostic parameters in the prediction of successful SCS. METHODS: Patients were followed up for periods ranging from 6 months to 15 years with a mean follow-up of 66 months. The mean age of the 150 men and 85 women in the study was 51.4 years. Indications for SCS included failed back syndrome (114 patients), peripheral vascular disease (39 patients), peripheral neuropathy (30 patients), multiple sclerosis (13 patients), reflex sympathetic dystrophy (13 patients), and other etiologies of chronic intractable pain (26 patients). RESULTS: One hundred and eighty-nine patients received permanent devices; 111 (59%) of these patients continue to receive satisfactory pain relief. Pain attributable to failed back syndrome, reflex sympathetic dystrophy, peripheral vascular disease of lower limbs, multiple sclerosis, and peripheral neuropathy responded favorably to spinal cord stimulation. In contrast, paraplegic pain, cauda equina syndrome, stump pain, phantom limb pain, and primary bone and joint disease pain did not respond as well. Cases of cauda equina injury had promising initial pain relief, but gradually declined after a few years. After long-term follow-up, 47 of the 111 successfully implanted patients were gainfully employed, compared with 22 patients before implantation. The successful patients reported improvements in daily living as well as a decrease in analgesic usage. Multipolar stimulation systems were significantly more reliable (p < 0.001) than unipolar systems. Complications included hardware malfunction, electrode displacement, infection, and tolerance. CONCLUSION: Aside from etiologies of pain syndromes as a prognostic factor, we have identified other parameters of success. In patients who have undergone previous surgical procedures, the shorter the duration of time to implantation, the greater the rate of success (p < 0.001). The diagnosis of failed back syndrome must be considered a confounding factor in our analysis. Those patients whose pain did not follow a surgical procedure had better responses to SCS than patients who had multiple surgical procedures prior to their first implant. The advent of multipolar systems has significantly improved clinical reliability over unipolar systems. Age, sex, and laterality of pain did not prove to be of significance.     

Treatment with enalapril modifies the pain perception pattern in hypertensive patients

The cardiovascular system shares numerous anatomic and functional pathways with the antinociceptive network. The aim of this study was to investigate whether angiotensin-converting enzyme (ACE) inhibitor treatment could affect hypertension-related hypalgesia. Twenty-five untreated hypertensive patients, together with a control group of 14 normotensive subjects, underwent dental pain perception evaluation by means of a pulpar test (graded increase of test current applied to healthy teeth). After the evaluation of the dental pain threshold (occurrence of pulp sensation) and tolerance (time when the subjects asked for the test to be stopped), all the subjects underwent a 24-hour ambulatory blood pressure monitoring. The hypertensive group then was treated with 20 mg/d enalapril, whereas the normotensive subjects remained without any treatment. After a time interval of 6+/-2 months, the dental pain sensitivity was retested in all the subjects, and ambulatory blood pressure was recorded during treatment in the hypertensive patients. At the first assessment, hypertensive patients showed a higher pain threshold than normotensive subjects (P<.001). On retesting of pain sensitivity in hypertensive patients, a significant decrease of both pain threshold and tolerance, leading to their normalization, was observed during treatment (P<.001 and P<.005, respectively), in the presence of reduced 24-hour and office blood pressure values. A slight, though significant, correlation was observed between variations in pain tolerance and baseline blood pressure changes occurring during treatment. During follow-up, the normotensive subjects did not show any significant pain perception or office blood pressure changes. Hypertension-related hypalgesia was confirmed. Mechanisms acting both through lowering of blood pressure and specific pharmacodynamic properties may account for the normalization of pain sensitivity observed in hypertensive patients during treatment with ACE inhibitors.     

Significance of the BTA test in bladder cancer: a multicenter trial. BTA Study Group Japan

Complex regional pain syndrome (CRPS) is a progressive, chronic illness that is enigmatic because the mechanisms for its pathogenesis have yet to be determined. Syndromes synonymous with CRPS are reflex sympathetic dystrophy, reflex neurovascular dystrophy, causalgia, algoneurodystrophy, sympathetically maintained pain, clenched fist syndrome, and Sudek's syndrome. The diagnosis of CRPS is categorized into three stages: acute, dystrophic, and atrophic. CRPS is most often precipitated by peripheral trauma (crushing injuries, lacerations, fractures, sprains, burns, or surgery) to soft tissue or nerve complexes. The pathogenesis for CRPS has been speculated as being either a disease process of the peripheral nerves, a disease process of peripheral soft tissue, or a disease process of the spinal cord. Patients suffering from CRPS may be limited in their ability to function in a self-directed, independent fashion. A longitudinal study of CRPS on 1,348 patients revealed that 96% of the study subjects still suffer some pain and disability regardless of the duration of the disease or course of treatment. Although the primary etiology for CRPS is not clearly understood, key progress has been made in terms of establishing a psychological as well as therapeutic treatment plan once the diagnosis has been made.     

Apolipoprotein E genotypes in a neuropathological series from the Consortium to Establish a Registry for Alzheimer''s Disease

A new classification system, termed complex regional pain syndromes types I and II, has been devised to replace the nomenclature of pain disorders previously termed reflex sympathetic dystrophy and causalgia. CRPS type I does not have identifiable major nerve injury, whereas CRPS type II has an identifiable major nerve injury. The classification is based on clinical symptoms and signs without incorporating any mechanistic connotations. These CRPS disorders may have SMP, SIP, or both.     

Balloon atrial septostomy under two-dimensional echocardiographic control: a new outlook

The comorbidity of eating disorders and reflex sympathetic dystrophy syndrome in the same patients raises the possibility of a common pathway for both conditions. Reflex sympathetic dystrophy syndrome may be manifesting itself in those individuals who have sympathetic overdrive. Microtrauma, often induced by compulsive exercise, and depression may be contributory factors. It is recommended that: patients with eating disorders who develop pain in an extremity should be investigated for possible reflex sympathetic dystrophy syndrome; patients with reflex sympathetic dystrophy syndrome should be discouraged from dieting, and eating disorders should be suspected if they begin to lose weight or are already malnourished.     

Pharyngo-UES contractile reflex in patients with posterior laryngitis

BACKGROUND: Earlier studies have shown that stimulation of the human pharynx by injection of minute amounts of water stimulates the pharyngo-UES contractile reflex. It has been suggested that this reflex may be activated during pharyngeal reflux of gastric and/or esophageal content, thus increasing the UES pressure and possibly preventing further entry of the refluxate into the pharynx. However, the integrity of this reflex in patients with posterior laryngitis has not been studied. AIM: Evaluate the pharyngo-UES contractile reflex in a group of patients with objective findings of posterior laryngitis. METHODS: Fourteen consecutive patients with posterior laryngitis (mean age, 48+/-6 y) and 13 healthy volunteers (mean age, 53+/-6 y) were studied by concurrent pharyngeal water stimulation and UES manometry. RESULTS: The threshold volume required to evoke the pharyngo-UES contractile reflex in the laryngitis group (0.4+/-0.05 mL) was significantly higher than that of the control (0.2+/-0.04 mL) (P < .05). Following stimulation of the pharyngo-UES contractile reflex, the maximum postinjection pressure in patients (75+/-6 mm Hg) was similar to that of the controls (78+/-6 mm Hg). The percent increase in UES pressure following stimulation of the reflex in the laryngitis group (99%+/-15%) was significantly higher than that of controls (55%+/-11%) (P < .05). CONCLUSIONS: Compared with normal controls, a significantly larger volume of liquid is required to trigger this reflex in patients with posterior laryngitis. When triggered, the maximum UES pressure induced by the pharyngo-UES contractile reflex is similar between the two groups. These findings suggest an altered afferent sensory limb of this reflex in patients with posterior laryngitis.     

The reflex sympathetic dystrophy syndrome in patients who have had a spinal cord injury

Patients suffering from a spinal cord injury often present with a pain syndrome. Although the reflex sympathetic syndrome is a common diagnosis in some forms of neurological disease such as patients with a stroke, it is less frequent in those with a spinal lesion. The authors report eight patients with reflex sympathetic dystrophy who had a spinal cord injury. The diagnosis and treatment are discussed along with a review of literature.     

Urological symptomatology in patients with reflex sympathetic dystrophy

PURPOSE: We determined the effect of reflex sympathetic dystrophy on lower urinary tract function. MATERIALS AND METHODS: A total of 20 consecutive patients (16 women and 4 men) with neurologically verified reflex sympathetic dystrophy was referred for voiding symptoms, including urgency, frequency, incontinence and urinary retention. No patient had had voiding symptoms before the initial trauma that induced reflex sympathetic dystrophy. Evaluation included medical history, physical examination, video urodynamic testing and cystoscopy. RESULTS: Mean patient age was 43.4 +/- 10.2 years (range 28 to 58) and mean duration of urological symptoms was 4.9 +/- 3.6 years (range 1 to 14). Urodynamic study demonstrated a mean cystometric bladder capacity of 417 +/- 182 ml. (range 120 to 700). The urodynamic diagnoses included detrusor hyperreflexia in 8 patients, detrusor areflexia in 8, sensory urgency in 3 and detrusor hyperreflexia with detrusor-external sphincter dyssynergia in 1. In 4 women genuine stress urinary incontinence was also documented urodynamically. CONCLUSIONS: Reflex sympathetic dystrophy may have a profound effect on detrusor and sphincter function.     

Differential effects of selective beta-adrenergic blockade on insulin sensitivity and release in control subjects and in patients with angina and normal coronary arteries (syndrome X)

AIMS: Betablockers are very effective in patients with angina and angiographically smooth coronary arteries (syndrome X), but may exacerbate the state of insulin resistance that is known to be present in such patients. The aim of the study was to evaluate the effects of short-term treatment with atenolol on carbohydrate metabolism in syndrome X patients, as compared to normal subjects. METHODS AND RESULTS: Seventeen patients (15 females, 55 +/- 8 years, BMI 23.4 +/- 2.7 kg/m2) and 11 controls (5 females, 50 +/- 7 years, BMI 23.1 +/- 2.0 kg/m2) were studied twice by an intravenous glucose tolerance test (IVGTT, 0.5 g/kg) after ten days of both placebo and atenolol (100 mg o.d.), given in random order. Metabolic indices measuring glucose effectiveness and insulin sensitivity were derived from minimal model analysis of the glucose and insulin profiles measured during the IVGTT. Indices of first- and second-phase insulin release were also calculated from the IVGTT insulin response. Atenolol had different metabolic effects on normal subjects and syndrome X patients. Despite the fact that the drug was found to be effective in relieving symptoms of chest pain, it induced a significant (p < 0.05) worsening of insulin resistance in syndrome X patients. No such effect was observed in control subjects. On the other hand, atenolol produced a marked reduction (40%, p < 0.05) of first-phase insulin release in control subjects, but no significant change of the same index in syndrome X patients. CONCLUSION: These results show that betablockers are very effective for controlling symptoms and improving quality of life in syndrome X patients. However, they appear to further impair the ability to dispose glucose. Long-term studies on the net effects of beta-blockade administration for the treatment of such patients are warranted.     

Pretherapy dental decisions in patients with head and neck cancer. A proposed model for dental decision support

OBJECTIVE: Sensory and motor abnormalities are common among patients with complex regional pain syndrome (CRPS). The purpose of the present study was to define and characterize these abnormalities and to develop a hypothesis regarding the area of the central nervous system from which they derive. DESIGN: Data were acquired from study subjects using clinical examination and quantitative assessment of neurological function. Subjects were divided into four groups. CRPS patients were differentiated into two groups based on the presence or absence of sensory deficit on the face to clinical examination. The other two groups were composed of patients with other chronic pain syndromes and normal individuals without chronic pain or disability. Clinical and quantitative data were compared between groups. PATIENTS: One hundred forty-five CRPS patients, 69 patients with other pain conditions, and 26 normal individuals were studied. RESULTS: A high incidence of trigeminal hypoesthesia was observed in CRPS patients. CRPS patients with trigeminal hypoesthesia manifested bilateral deficits of sensory function, with a predominant hemilateral pattern. These patients also manifested bilateral motor weakness with a more prominent hemiparetic pattern. Both sensory and motor deficits were greatest ipsilateral to the painful side of the body. These features differed significantly from those of CRPS patients lacking clinical trigeminal deficit, other pain patients, and normals. A lower cranial nerve abnormality (sternocleidomastoid weakness) and a myelopathic feature (Hoffman's reflex) were more common in CRPS patients with trigeminal hypoesthesia. CONCLUSIONS: Nearly half of CRPS patients had abnormalities of spinothalamic, trigeminothalamic, and corticospinal function that may represent dysfunction of the medulla. One-third of the remaining CRPS patients had neuroimaging evidence of spinal cord or brain pathology. The majority of CRPS patients in this study have measurable abnormalities of the sensory and motor systems or neuroimaging evidence of spinal cord or brain dysfunction.     

Pain, negative mood, and perceived support in chronic pain patients: A daily diary study of people with reflex sympathetic dystrophy syndrome.

Chronic pain patients show substantial psychological distress, including depressed mood, anxiety, and anger. Nevertheless, the causal role of negative mood in the course of chronic pain conditions remains unclear. This study prospectively investigated the relationship between daily pain, negative mood, and social support in 109 people with reflex sympathetic dystrophy syndrome. Participants completed 28 daily diaries that included questions about pain, mood, and perceived support. Time-lagged within-subject analyses indicated that pain led to increases in depressed, anxious, and angry mood. Depressed mood, but not anxiety or anger, contributed to increases in pain. Perceived support had both main and buffering (interaction) effects on negative mood and a main effect on pain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Occurrence and etiology of tooth caries in wearers of fixed dentures during the war]

This retrospective study was undertaken to determine the usefulness of intravenous regional anesthetic (IVRA) blocks containing ketorolac and lidocaine in the management of sympathetically-mediated pain, and to determine what factors, if any, predicted success with this technique. Sixty-one patients with reflex sympathetic dystrophy presenting to a university-affiliated teaching hospital's pain management center were evaluated. Patients underwent one or more treatments with IVRA blocks containing ketorolac and lidocaine. The duration of pain, site of extremity affected, pain symptomatology, duration of relief from the first IVRA block, absence of pain following a series of IVRA blocks and side-effects from the IVRA blocks were determined. Of the 61 patients, 16 had complete response (26 percent), 26 had a partial response (43 percent) and 19 had no response (31 percent) to the ketorolac-containing IVRA. The only symptom which predicted a failure with this therapy was allodynia. No patient had serious side effects from the IVRA block; dizziness following tourniquet release occurred in 41 percent (n = 25) of the patients. IVRA block containing ketorolac is a useful and minimally invasive technique for the management of patients with reflex sympathetic dystrophy.     

Changes in pain perception after treatment for chronic pain

Pain threshold, sensitivity, response bias and ability to discriminate were measured before and after treatment for 15 improved and 15 unimproved chronic pain patients diagnosed as having myofascial pain dysfunction (MPD) syndrome, There were no differences between the groups before treatment. After treatment, the improved group showed an increase in pain threshold, sensitivity and ability to discriminate between different levels of painful stimulation and a decrease in response bias to report pain. The unimproved group showed no changes.     

Current principles of multidisciplinary treatment of pain in orthopedic clinics

Differentiated strategy of treating patients with acute and chronic pain is developed. Preemptive analgesia is a priority trend in the treatment of acute postoperative pain. The most prevalent method of postoperative analgesia is prolonged opioid epidural analgesia carried out in intensive care wards and other wards by an acute pain management team. For treating patients with chronic painful syndromes, protocols of initial clinical and diagnostic evaluation are developed, permitting the choice of individual treatment strategy. Differentiated complex drug therapy planned with consideration for individual course of the painful syndrome is the basis of treating patients with phantom pain syndrome. Algorithms of differentiated therapy of radicular and spondylogenic pain are designed. Stage-by-stage analysis of treatment efficacy is carried out using modern electrophysiological methods. Realization of the proposed organization principles improved the efficacy of postoperative analgesia to 88.2%, prevented the development of postoperative painful syndrome in 35.6% cases, decreased the incidence of phantom pain syndrome after amputation of the limb from 63.3 to 31.6% and increased the efficacy of this syndrome treatment to 70.1%, and increased the efficacy of treating vertebrogenic painful syndromes to 82.3%.     

Fibromyalgia--are there different mechanisms in the processing of pain? A double blind crossover comparison of analgesic drugs

OBJECTIVE: Pain was analyzed in patients with fibromyalgia (FM) in a randomized, double blind, crossover study using intravenous (i.v.) administration of different drugs. METHODS: In 18 patients with FM muscle pain to i.v. administration of morphine (0.3 mg/kg), lidocaine (5 mg/kg), ketamine (0.3 mg/kg), or saline was studied. Spontaneous pain intensity, muscle strength, static muscle endurance, pressure pain threshold, and pain tolerance at tender points and non-tender point areas were followed. Drug plasma concentrations and effects on physical functioning ability score (FIQ) were recorded. A personality inventory (KSP) was used to related pain response to personality traits. RESULTS: Thirteen patients responded to one or several of the drugs, but not to placebo. Two patients were placebo responders responding to all 4 infusions. Three were nonresponders responding to no infusions. Seven of the responders had a reduction in pain for 1-5 days. Pressure pain threshold and pain tolerance increased significantly in responders. Plasma concentrations were similar in responders and nonresponders. FIQ values improved significantly after the ketamine infusion. Responders scored higher on KSP scales for somatic anxiety, muscular tension, and psychasthenia compared with healthy controls. CONCLUSION: FM diagnosed according to the American College of Rheumatology criteria seems to include patients with different pain processing mechanisms. A pharmacological pain analysis with subdivision into responders and nonresponders might be considered before instituting therapeutic interventions or research.     

Decreased pain threshold and tolerance in patients with chronic tension headache

Nociceptive processing was studied in 40 patients with chronic tension-type headache and in 40 healthy controls. We found that pericranial tenderness recorded by manual palpation was considerably higher in patients than in controls (p < or = 0.0002). Pressure pain detection and tolerance thresholds recorded in the finger, by means of a pressure algometer, were significantly lower in patients than in controls (p < or = 0.0009), and a non-significant similar trend was observed in the temple (p < or = 0.12). Detection and tolerance thresholds were decreased to a similar degree in patients compared with controls, and pain thresholds recorded in the finger and in the temple were highly correlated (r = 0.84, p < 0.0001). The electrical pain threshold at the labial commissure, by means of an electrical stimulator, was significantly decreased in patients compared with controls (p = 0.03). All of the examined pain thresholds were significantly correlated to the pericranial tenderness recorded by palpation (r = -0.35 to -0.53, p < or = 0.03). We conclude that the present finding of a general hypersensitivity to pain stimuli in chronic tension-type headache indicates that central factors play an important role in the pathogenesis of this disorder.     

Lack of association between both insulin resistance and plasma insulin levels with blood pressure values in essential hypertension

AIM: To evaluate the role of insulin resistance and hyperinsulinaemia in the genesis of essential arterial hypertension (EAHT). SUBJECTS AND METHODS: We studied 49 patients (age 44 +/- 8 y., body mass index (BMI: 29.5 +/- 3.2 kg.m-2) with mild or moderate EAHT (systolic blood pressure: 156 +/- 13 mmHg, diastolic blood pressure: 100 +/- 6 mmHg). Patients with BMI > 27 kg.m-2 were classed as obese. Arterial pressure was measured with a mercury sphygmomanometer after the patient had been lying down for 15 min. For each patient, the results of a frequently sampled intravenous glucose tolerance test (FSIGT) were used to estimate insulin sensitivity (using the minimal model of glucose metabolism) and to characterize insulin secretion in response to intravenous glucose (area of the insulin curve above basal during the 180 min of the FSIGT test). Correlations were evaluated by means of Spearman's correlation coefficient. RESULTS: Neither fasting insulinaemia, glucose-induced insulin secretion nor insulin sensitivity correlated significantly with arterial pressure, either in the whole sample or in the obese and non-obese subsamples. CONCLUSIONS: These results suggest that neither insulin nor insulin sensitivity are important physiological regulators of arterial pressure, and lend no support to the hypothesis that insulin is related to essential arterial hypertension.