R.J. Evans

Amitriptyline versus maprotiline in postherpetic neuralgia: a randomized, double-blind, crossover trial.

&NA; Amitriptyline (AT) relieves some patients with postherpetic neuralgia (PHN). Many patients suffer side effects and better therapies are necessary. The aim of this study was to evaluate the efficacy of maprotiline (MT) (noradrenergic) compared to AT (mixed noradrenergic and serotonergic) in this disorder. Thirty‐five patients entered a randomized, double‐blind, crossover trial of these two agents. We found that MT relieved PHN in many patients but was not as effective as AT. Side effects were troublesome with both agents. Relief of steady pain, brief pain and pain on tactile stimulation occurred. Four groups of responses were identified. Some patients reported relief with both agents, some with neither agent and others with only one of the drugs. Most patients were not depressed and analgesia was observed to occur without change in depression ratings in most patients who responded. This result provides evidence that in some patients AT may act via a selective noradrenergic mechanism in relieving PHN and that individuals may differ in the balance and type of neurotransmitters inhibiting pain. Selective noradrenergic agents may be effective if AT fails.

Alexithymia in somatoform disorder patients with chronic pain

The prevalence of alexithymia in fifty-five motor vehicle accident survivors who had chronic pain complaints and met DSM-III-R criteria for somatoform pain disorder was 53%. Alexithymic and non-alexithymic patients did not differ on self-reports of current pain severity or in the number of pain locations. Alexithymic patients were found to use significantly more words to describe their pain, suggesting they may have a more diffuse style in communicating their pain experience.

Post-herpetic neuralgia: post-mortem analysis of a case.

&NA; The morphological and biochemical substrates of the severe pain in post‐herpetic neuralgia (PHN) are unclear. This report is an autopsy study of a 67‐year‐old male with severe PHN during the last 5 years of his life over the right T7‐8 dermatomes. The dorsal horn of the thoracic spinal cord of the affected side was atrophic from T4 to T8, with loss of both myelin and axons. Despite this, only the T8 ganglion was affected by fibrosis and cell loss and only the nerve roots at that level appeared affected. Markers of unmyelinated afferents (substance P), substantia gelatinosa neurons (opiate receptors), glial cells (glial fibrillary acidic protein), and descending spinal projections (dopamine‐&bgr;‐hydroxylase and serotonin) were not different at affected versus non‐affected spinal cord levels. The pain of PHN may result from the uninhibited activity of unmyelinated primary afferents as a result of the loss of myelinated afferent fibers and the possible presence of hypersensitive neurons in the dorsal horn.

The prognosis with postherpetic neuralgia.

One hundred and fifty-six patients with moderate to severe postherpetic neuralgia (PHN) were followed for up to 11 years. Nearly half of all patients were doing well at the final assessment (median 2 years) and more than half of these were on no therapy at this time. The most commonly used agents associated with a good outcome were antidepressants, topical capsaicin and analgesics of various kinds. Longer duration PHN appeared to have a worse prognosis. More of these patients were noted to be using some form of treatment at follow up. A group of patients seemed to follow a progressive course and were refractory to all treatments used in this study.

Road vehicle accidents and phobias in 60 patients with fibromyalgia

Abstract Sixty patients referred consecutively to a multidisciplinary pain clinic because of fibromyalgia were investigated by Structured Clinical Interview for DSM- III-R. Phobias and posttraumatic stress disorder were 3.2 times more common in 33 (48.4%) victims of minor road vehicle accidents than in 27 (14.8%) patients with nonvehicular onset of pain. Neither affective disorder (28.3%) nor uncomplicated somato- form pain disorder (18.2%) clustered with road vehicle accidents. Frightening accidents may more than double the risk for phobic disorder.

The hot foot syndrome: Evans' sign and the old way

BACKGROUNDnPelvic cancers such as cancer of the cervix can spread locally to involve adjacent structures such as the lumbosacral plexus and the sympathetic chain. When this happens the prognosis is usually poor. An early suspicion of recurrence may result in investigation leading to earlier and better treatment. A physical sign that may be an early and only sign of recurrence is described.nnnOBJECTIVEnTo report the late Dr Ramon Evans unpublished case series of the hot foot syndrome due to (mostly malignant) retroperitoneal disease. This unique contribution is an opportunity to pay tribute to a man who was a meticulous recorder of the patient narrative and practitioner of a detailed and comprehensive physical examination.nnnMETHODSnA longitudinal, observational, retrospective, descriptive study is reported. Data were collected from a convenience sample of 86xa0patients, 75 of whom had retroperitoneal cancer and 11 of whom were diagnosed with other conditions in that area. Patients referred to the Smythe Pain Clinic were seen at both the Princess Margaret Hospital and Toronto General Hospital in Toronto, Ontario, in the 1970s. They were referred with intractable pain in the leg or back and often a history of a treated abdominal or pelvic cancer in the previous months or years. Baseline demographic data were collected including age, sex, diagnosis, pain location, characteristics and severity, physical findings, investigations and mortality.nnnRESULTSnThe 86 subjects comprised 27 men and 59 women. Carcinoma of the cervix was the most common tumour. Most had a presenting complaint of leg pain. Neurological physical signs were demonstrated in the lower extremities in 44%; however, 56% (48 patients) had only an ipsilateral, warm, dry hot foot due to sympathetic deafferentation. The prognosis for the underlying illness was poor for the malignant group.nnnDISCUSSIONnSympathetic interruption by cancer is well known in apical lung cancer as the tumour spreads upwards to involve the inferior brachial plexus. An analogous situation occurs as cancers, such as that of the cervix, spread laterally to invade the lumbosacral plexus and sympathetic chain. Signs of sympathetic deafferentation (the hot foot) may be the earliest and only sign in this situation. This sign may be missed unless it is anticipated and a thorough physical examination carried out.nnnCONCLUSIONnEvans sign is important because it may be an early and solitary sign of retroperitoneal recurrence of pelvic (cervix, rectum, bladder, ovary and prostate) cancers. Recognition of this finding when intractable pain in the back and leg occurs with a history of this type of cancer could lead to earlier and more successful treatment.

Chronic cluster headache

Aim of investigation: This study reports the clinical features and treatment of 60 patients with chronic cluster headache (CCH) >6 months. Median follow-up was 4 years in 45 patients. Method: This study is a retrospective study and includes all patients seen in a neurological practice and in a pain clinic over a period of 15 years. An attempt was made to contact all patients to determine the status to date. Results: Prophylactic therapy was most successful with the use of lithium carbonate and methysergide. Indomethacin, prednisone, calcium blockers, pizotyline, propranolol, chlorpromazine and ergotamine were all rarely effective. Of symptomatic therapies, ergotamine was successful by injection, inhalation or sublingually, and overall was the most effective drug for aborting the headache. A limitation was a tendency to exceed the weeklv maximum of 10 mgms. Oxygen inhalation was useful in a few patients. Long term follow-up revealed 59% of patients were either free of headache (39%) or categorized as satisfactory by patient and examiner (26%). Fourteen (52%) of these had undergone a surgical procedure. Conclusions: The authors conclude that CCH is a particularly intractable form of headache. Treatment is largely trial and error. Often, initially effective medication fails in the long term, necessitating a search for alternative therapy. The most effective therapy appears to be lithium, combined with symptomatic use of sublingual or inhaled ergotamine or oxygen. The long term outlook may be better than previously supposed.

Psychiatric diagnoses in 61 unselected patients with chronic generalized muscle tension pain

AIM OF INVESTIGATION: The purpose of this study was to examine: a) the effectiveness of a cognitive behavioral program for groups of pain patients with a variety of painproblems, b) the contribution of a component analysis in enhancing the effectiveness of the program and c) which patients do benefit most of such a program. METHOD: Elements of the program are: (mult1dlsclpllnary) education, groupdiscussion, assertion training, rational emotive therapy, (cognitive) copingskills, management of (dally) activities, relaxation, partner participation, physical therapy (lncl.swimmlng) and psychomotorlc therapy. Each group consisted of about 6 patients. Patients underwent a three-month program of two weekly sessions, followed by a six month period of monthly boostersessions. RESULTS: Although the data are far from conclusive, findings suggest that patients who participated in the program showed a decrease in emotional distress, subjective pain, painbehavior, catastrophizing their painproblems, medical consumption and an increase in assertion, activity levels and self-efficacy. CONCLUSIONS: The findings suggest that this program may be succesfully administered on an outpatient basis. Component analysis appears to be useful1 in enhancing the effectiveness of the program. However careful1 selection of patients is needed. Patients who seem to benefit most of this approach are those whose painproblem is related with activity-factors (low and high activity levels). It is assumed that patients with emotional problems expressed in the language of pain (l.e.traumatic childhood experiences, grief) may benefit more of a treatment focussing on such emotional problems. Finally, the next step in the evaluation of the program is to investigate its effectlviness in a controlled fashion.