Thermographic validation of physical complaints in 'psychogenic pain' patients

Concomitant Sympathetically Mediated Pain and Myofascial Trigger Point Pain

It is not sufficiently well recognised that the reflex sympathetic dystrophy syndrome (RSDS) and the myofascial pain syndrome (MPS) may develop concomitantly. This happens because they have similar aetiological factors, with trauma being by far the commonest.

Everyone is liable to develop nociceptor pain as a result of trauma-induced activation and sensitisation of C afferent skin and Group IV muscle nociceptors; also A-β mediated pain as a result of the sensory afferent barrage produced by these nociceptors giving rise to sensitisation of dorsal horn transmission neurones.

With most people these neural changes lead only to the development of MPS. In a minority of people, possibly those with a genetically determined predisposition, this sensory afferent barrage also causes changes to take place in the sympathetic nervous system, with the development of a characteristic burning type of sympathetically mediated pain. This may develop alone or in association with myofascial trigger point pain.

There is much controversy concerning the mechanisms for development of RSDS pain. One theory is that the pain develops as a result of the nociceptor-induced sensory afferent barrage setting up aberrant sympathetic efferent activity. This results in the release of noradrenaline which binds to α-1 adrenoreceptors in the walls of the nociceptors, exciting them further. Much research, however, still has to be done before the development of sympathetically maintained pain can be adequately explained.

It is stressed that for the successful treatment of RSDS early diagnosis is essential. Treatment involves sympathetic blockade either by the injection of local anaesthetic into a sympathetic ganglion, or by the regional infusion of a catecholamine depleting drug.

Sympathetically maintained pain is morphine resistant and is therefore unlikely to be relieved by acupuncture, the analgesic effect of which is mediated by opioid peptides. The main place for acupuncture is in the treatment of concomitant myofascial trigger point pain.

It is emphasised that in all cases of RSDS it is essential to search for myofascial trigger points and, when present, to deactivate these by means of acupuncture stimulation of A-δ nerve fibres present in the skin and subcutaneous tissues at the trigger point sites.

The Challenge to Manage Reflex Sympathetic Dystrophy/Complex Regional Pain Syndrome

The challenge to understand reflex sympathetic dystrophy/complex regional pain syndrome may require a better understanding of the complex relationship between the central and peripheral nervous systems. There is no comprehensive hypothesis that clearly explains the etiology and no uniformly successful treatment method. This brief summary of the challenge reviews some of what is known, hypothesizes a possible etiologic mechanism, and proposes 10 common-sense principles for management that recognizes the handicap of limited knowledge.

Reflex sympathetic dystrophy syndrome

Reflex sympathetic dystrophy is a condition characterized by unrelenting pain, swelling, discoloration, temperature, and physical changes in the affected body part that are life-altering for the patient and the family. Early diagnosis and treatment are essential to minimize the progressive disability from this disorder that results in limb pain, physical changes, and deformity. This article considers the current understanding of RSDS in terms of historical perspective, clinical features, pathophysiologic theories, diagnostic evaluation, treatment options, and nursing care.

Upper cervical chiropractic management of a patient with Parkinson's disease: a case report

OBJECTIVE

To discuss the use of upper cervical chiropractic management in managing a single patient with Parkinson's disease and to describe the clinical picture of the disease.

CLINICAL FEATURES

A 60-year-old man was diagnosed with Parkinson's disease at age 53 after a twitch developed in his left fifth finger. He later developed rigidity in his left leg, body tremor, slurring of speech, and memory loss among other findings.

INTERVENTION AND OUTCOME

This subject was managed with upper cervical chiropractic care for 9 months. Analysis of precision upper cervical radiographs determined upper cervical mis-alignment. Neurophysiology was monitored with paraspinal digital infrared imaging. This patient was placed on a specially designed knee-chest table for adjustment, which was delivered by hand to the first cervical vertebrae, according to radiographic findings. Evaluation of Parkinson's symptoms occurred by doctor's observation, the patient's subjective description of symptoms, and use of the Unified Parkinson's Disease Rating Scale. Reevaluations demonstrated a marked improvement in both subjective and objective findings.

CONCLUSION

Upper cervical chiropractic care aided by cervical radiographs and thermal imaging had a successful outcome for a patient with Parkinson's disease. Further investigation into upper cervical injury as a contributing factor to Parkinson's disease should be considered.

Reflex Sympathetic Dystrophy in the Upper Extremity

The diagnosis and treatment of pain are among the most challenging problems facing orthopaedic surgeons, and reflex sympathetic dystrophy is probably the most frustrating and difficult pain syndrome to manage. Pain, swelling, and autonomic dysfunction are cardinal signs of the condition. Although the pathogenesis is still unclear, many theories have been proposed. Because reflex sympathetic dystrophy is sympathetically mediated, diagnosis can be confirmed on the basis of response of the pain to sympathetic blockade. Treatment may include an appropriate exercise program, a-adrenergic blocking agents, mood-elevating drugs, calcium channel blockers, intravenous regional blocks, and stellate ganglion blocks. Recent additions to therapy include electroacupuncture, transcutaneous electrical nerve stimulation, and biofeedback. Prognosis is, at best, guarded with this perplexing condition, but the best response is obtained when diagnosis is made early (within the first 2 or 3 weeks after injury) and treatment is initiated during the first stage of the disease.

Validation of thermography in the diagnosis of reflex sympathetic dystrophy

OBJECTIVES

To examine the validity of several thermogram-derived indices of autonomic functioning in the diagnosis of reflex sympathetic dystrophy (RSD).

DESIGN

A series of chronic pain patients were classified diagnostically based on thermogram results using discriminant function analysis, and validity measures (e.g., sensitivity, specificity) were used to determine the accuracy of computerized thermographic pixel analysis in discriminating RSD from other pathology.

SETTING

The study was conducted at the Rush Pain Center, a multidisciplinary outpatient pain clinic.

PATIENTS

A series of 46 chronic pain patients referred for suspected sympathetically mediated pain.

INTERVENTIONS

All patients underwent computerized thermographic examination under a baseline condition after acclimating to a climate-controlled room, immediately after a cold challenge was applied to the contralateral uninvolved extremity (4 degrees C for 90 s) and 20 min after the cold challenge.

OUTCOME MEASURES

Temperature during the three experimental periods, degree of temperature asymmetry between affected and nonaffected limbs during the three periods, response to cold challenge, and recovery following cold challenge were measured.

RESULTS

Temperature asymmetry accurately discriminated between RSD and non-RSD patients, with the most accurate asymmetry measures obtained at baseline. Responses to cold challenge and actual temperature values did not discriminate between RSD and non-RSD pain patients.

CONCLUSIONS

Thermography can be a useful component of RSD diagnosis. In situations where sensitivity and specificity are equally important, an asymmetry cutoff of 0.6 degree C appears optimal. If specificity (i.e., accurately ruling out non-RSD cases) is more important, a cutoff of 0.8 degree C or 1.0 degree C may be considered as well.

Regional hypothermia in response to minor injury

Minor injuries are sometimes followed by a potentially disabling syndrome of hyperalgesia, hyperesthesia, allodynia, and sudomotor disturbance as well as, eventually, weakness, muscle atrophy, trophic skin changes, and bone and joint abnormalities. Vasomotor changes frequently present as hypothermia or hyperthermia. Most of the literature refers to this syndrome as reflex sympathetic dystrophy (RSD). To observe possible early RSD changes, we studied 1000 military recruits before and during basic training. Evaluations consisted of lower limb clinical examinations and pain assessment. Infrared images were taken of anterior, posterior, medial, lateral legs, and plantar surface of the feet. If the clinical examination suggested a possible stress fracture, a bone scan was performed. Recruits were studied before training and again each time musculoskeletal complaints arose. The controls were recruits tested before the onset of training who had no musculoskeletal complaints. Two-hundred seven soldiers were injured. Regional hypothermia was noted in 8.6% of all thermograms, with 75% on the left and 25% on the right. The most common injuries causing this phenomenon were ankle pain/sprain and minor foot stress fractures, especially the left metatarsals. Hypothermia occurred within 24 to 48 h, usually beginning in the periphery and ascending proximally, lasting a few days to 6 wk (end of study). None of the recruits developed the full syndrome of RSD during the study period. Whether the continued training, even though modified, helped to prevent this complication or the observed post-traumatic hypothermia has no relationship to RSD needs to be determined.

Patterns of thermoregulation associated with cold intolerance after digital replantation

Twelve patients with complete thumb amputations were analyzed to determine the interrelations between thermoregulation for pain and cold intolerance and sensory nerve recovery. Patients were examined at 3 months, 6 months, 1 year, and after 2 years following replantation. Medical thermography was introduced to assess postoperative circulation following digital replantation, while vasomotor tone was assessed by cold-stress plethysmography testing. Postoperative circulation was divided into two different patterns based upon skin temperature, the transition of which over time correlated well with sensory nerve recovery. Patients with cold intolerance showed a persistent vasoconstriction pattern, the cold change of which was objectively detected by thermography.

Future applications of electronic thermography

The dental literature does not yet indicate the full range of facial thermographic findings in health and disease. Thermography is not useful in assessing some common dental problems, such as periapical granuloma. Promising reports, however, support its use in the diagnosis of neuralgias and atypical odontalgia, TMJ, nerve damage and repair after oral surgery, and in evaluating local dental anesthesia. Unfortunately, few if any of these studies were properly designed or conducted, limiting current attempts to define the value of thermography in dentistry. Until this situation resolves, ET of the face, for use in dentistry, can only be considered an investigational procedure. More research will clarify the precise contribution of thermography to dental problems.

Thermography--its current diagnostic status in musculoskeletal medicine

OBJECTIVE

To evaluate the currently perceived status of thermography in the diagnosis of musculoskeletal disorders.

DATA SOURCES

Medical and legal journals published from 1956 onwards; report of the United States Office of Health Technology Assessment and personal communication with the author of that report.

STUDY SELECTION

Confined to application of thermography to musculoskeletal and neurological medicine.

DATA EXTRACTION AND SYNTHESIS

Weighted towards prospective and controlled studies.

CONCLUSION

Little evidence exists of any application of thermography in which it is unequivocally superior to conventional diagnostic imaging methods.

Quantification of thermal asymmetry. Part 2: Application in low-back pain and sciatica

Temperature differences between the lower extremities were measured using a computerized thermometric scanning system in order to compare the degree of thermal asymmetry in 144 patients with low-back pain. The patients displayed highly significant thermal asymmetries, with the involved limb being cooler (p less than 0.001). When asymmetries exceeded 1 standard deviation from the mean temperature of homologous regions measured in 90 normal control subjects, the positive predictive value of thermometry in detecting root impingement was 94.7% and the specificity was 87.5%. These values indicate that calculation of temperature asymmetry is particularly effective in evaluating reported pain in psychosocially affected patient populations in whom the chance of positive myelography or impaired root function is low. In this group of patients, thermometric study provides physicians with important information for proper decision making. The test can be performed to avoid more invasive and probably less revealing diagnostic or exploratory surgical procedures.

Sympathetic dysfunction in patients with persistent pain after prolapsed disc surgery. A thermographic study

Vasomotor function in the lower limbs was tested by means of thermography in 48 patients with and without residual complaints after surgery for a prolapsed intervertebral disc. There is a definite correlation between the severity of the complaints and the thermographic responses which corresponds well with the evidence for a sympathetic reflex dystrophy of the legs (causalgia).

Comparison of neurothermography and contrast myelography

Eighty consecutive patients who first had an electronic infrared thermogram (neurothermogram) and a subsequent oil myelogram were studied retrospectively. All patients had cervical and/or lumbosacral radiculopathy for 90 days. Negative neurothermograms were predictive of negative myelograms in 93% of our series. Positive neurothermograms were predictive of positive myelograms in 71% of the patients. The neurothermogram is not a specific test for intraspinal axis lesions as a cause of radiculopathy. Proximal neuropathic lesions of other causes will also produce abnormalities of the sympathetic autonomic (peripheral) nervous system. The major pathophysiologic findings detected by neurothermograms are complimentary to the EMG, NCVS, and late response techniques. Neurothermography was successful in predicting the outcome of myelography in 82% of patients in this study.

The noninvasive laboratory--history and future of thermography

A brief history of thermography and recent developments in instrumentation have been reviewed. Important applications are related to thrombophlebitis, the cerebral circulation, peripheral arterial abnormalities and medical-legal situations.

Normal thermographic standards for the cervical spine and upper extremities

Although thermography has been used for a variety of abnormal conditions, extensive data on large, relatively asymptomatic populations has heretofore not been available. More specifically, no data deal with the upper extremities and, more particularly, no analyses are based on simultaneous thermograms of the posterior neck and shoulders. The current study undertook this task. The results confirm the existence of thermal symmetry in the overwhelming majority of 100 normal relatively asymptomatic, actively employed factory workers. Conversely, if persistent, statistically significant thermal asymmetry exists, as outlined and correlates with patient symptomatology, an organic basis for it should be sought.

Liquid crystal thermography in the evaluation of chronic back pain: a comparative study

This research involves the relative value of liquid crystal contact thermography (LCT) as compared to the physical examination, myelography, electromyography and CT scanning in the examination of 155 chronic low back pain patients. Thermograms were interpreted by two independent examiners as positive for nerve root compromise. Results demonstrate excellent interobserver reliability when used for this specific purpose and respectable correlations with the physical examination and EMG studies were obtained. Somewhat less correlation was found between LCT and the diagnostic procedures of CT scanning and myelography, especially in the postoperated patient. Liquid crystal contact thermography shows some promise as an adjunctive diagnostic tool in the assessment of chronic back pain patients with radicular symptoms, especially where further surgery is contemplated and the more structural tests of CT scanning and myelography may be falsely positive as a result of previous back surgery.