The effects of non-painful transcutaneous electrical nerve stimulation on cutaneous pain threshold and muscular reflexes in normal men and in subjects with chronic pain.

In healthy subjects and in subjects with chronic myofascial pain of one lower limb, the following was measured in both lower limbs: (i) sequential Hoffman (H) reflex, (ii) sequential Achilles tendon (T) reflex, (iii) cutaneous pain threshold determined with electrical stimuli, before, during and after transcutaneous electrical nerve stimulation (TENS). In healthy subjects no significant differences were observed between the pain thresholds of the two limbs. During and after TENS, changes of the reflexes were related to the pain thresholds. In the pathological subjects a significant difference of pain threshold was present between the affected limb and the contralateral one. An important difference between healthy and pathological subjects is not the quality but the quantity of the changes induced by TENS, in the sense that the levels of inhibition and facilitation of the reflexes are more evident in patients with pain. Indeed, TENS induces a reset of sensory and of motor system and a parallel long lasting effect both on sensory and on muscular function, with concomitant pain relief in the pathological subjects.

Myocardial infarction without pain. A study of the sensory function of the upper limbs.

The sensory function of the upper limbs was examined in 18 subjects who had a myocardial infarction without a well-defined episode of chest pain. The cutaneous pain threshold was significantly higher than in normals. The ischaemia of the upper limbs induced patterns of sensations different from the normals, with onset of pain and of autonomic and coenaesthesic disturbances. These modifications of the sensory function are the same as observed in subjects with a previous painful infarction, but are quite different from those observed in patients with angina pectoris.

Cutaneous pain threshold changes after sympathetic block in reflex dystrophies.

In a group of 30 subjects suffering from sympathetic reflex dystrophies of the limbs, the sympathetic ganglia of the affected side were blocked with a local anesthetic. Using an original method, we measured the cutaneous pain threshold before the block and at prefixed intervals after the block during a period of 2 days. In all subjects the cutaneous pain threshold showed damped oscillations both in the limb ipsilateral to the block and in the contralateral one. The analysis of these oscillations showed: (a) that the sympathetic control of the cutaneous pain threshold may be exerted through a negative feedback loop (skin-afferent input-CNS-sympathetic output-skin); (b) that the afferent discharge of a limb controls the contralateral sympathetic output through central mechanisms.

Pain in early cancer of the lungs.

164 patients with early cancer of the lungs, i.e., without extrathoracic spread or distant metastasis, were examined. Subjective and objective characteristics of the pain were studied. A correlation was found between the location of the neoplasm, the location of the pain and the characteristics of the sensory changes. These observations may be a useful contribution to the early diagnosis of primary carcinomas of the lungs.

Lateralisation of pain in cluster headache.

In 27 patients with cluster headache a careful sensory examination of the entire body was performed. The exam included: the measurement of sensory thresholds with mechanical and electrical stimuli, the assessment of cutaneous and deep hyperalgesia and the ischaemic test of the upper limbs with limbs at rest. In most patients a lateralisation of the findings was observed: cutaneous and deep hyperalgesia were prevalent in the side of cluster headache attacks. The results indicate that in cluster headache, as in other pain syndromes, a lateralisation may be induced throughout the body, probably by phenomena of facilitation in the central nervous system and by activation of reflex arcs.

The use of pupillometry in joint and connective tissue diseases.

The central and peripheral nervous systems are variably affected in the rheumatic diseases. Automated standardized infrared pupillometry allows the safe, noninvasive assessment of the pupillary innervation. Pupillometry has already been used in studying the autonomic nervous system (ANS) in various rheumatic diseases. In systemic lupus erythematosus, the irideal parasympathetic branch of ANS was more affected then the sympathetic branch. In Sjögren's syndrome, signs of pupillary parasympathetic denervation have been reported. In rheumatoid arthritis, pupil parasympathetic dysfunction has been shown to correlate with ocular dryness. In systemic sclerosis (SSc), both sympathetic and parasympathetic irideal impairment have been demonstrated. Beside providing autonomic innervation, sensory nerves fibers are able to control iris diameter. Exogenous ocular instillation of substance P (SP), a sensory neuropeptide, can determine an omathropine-resistant, non-cholinergic myosis, acting on specific receptors present on the iris sphincter muscle. We first studied pupillary SP-ergic responsiveness in SSc, evaluating substance P (SP)-stimulated pupillary diameters by pupillometry. A higher basal and SP-stimulated myosis was found in lSSc versus both dSSc and controls, whereas no differences existed between dSSc and controls. From the literature, the pupillary parasympathetic nervous system seems to be more affected than the sympathetic branch of ANS in the rheumatic diseases characterized by an inflammatory status. However, we found in SSc both sympathetic and parasympathetic pupil control to be equally impaired. From our experience, we conclude that pupillary nervous control is differently affected in the two subsets of SSc, and that the SP-ergic system seems to be impaired only in lSSc.

Dimensions of psychological dysfunction in patients with fibromyalgia: development of an Italian questionnaire.

Our objective was to observe whether dysfunctional psychological dimensions of pain could be detected in fibromyalgia patients through the development of a new questionnaire. An original questionnaire composed of 51 items was given to 250 patients (185 females and 65 males, mean age 55+/-12.8 years) suffering from chronic fibromyalgia according to the criteria of the Multicenter Criteria Committee of the American College of Rheumatology. A Varimax computerized program of factorial analysis with orthogonal and oblique rotation of the axes was used to analyze the data. Five strong independent factors were identified: 1) catastrophizing and 2) external control beliefs (cognitive); 3) alexithymia (emotional); 4) restless behavior (behavioral); and 5) need for support (relational). Our questionnaire is a preliminary development of an Italian language psychological characterization of FM patients which may be a relevant and useful tool for the evaluation of the outcome of clinical/psychological treatment of FM.

Health-related quality of life in systemic sclerosis as measured by the Short Form 36: relationship with clinical and biologic markers.

OBJECTIVE: To evaluate health-related quality of life (HRQOL) in patients with systemic sclerosis (SSc) using the Short Form 36 (SF-36) and to correlate SF-36 scores with clinical and biologic markers. METHODS: The SF-36 was administered to 24 controls and 24 SSc patients. SSc patients also were evaluated for subset (limited SSc [lSSc] and diffuse SSc [dSSc]), age, disease duration, angiotensin-converting enzyme (ACE) levels, autoantibodies, and skin and internal organ involvement. RESULTS: The physical summary score (PSS) was lower in SSc patients than in controls (P < 0.05), whereas the mental summary score (MSS) was higher in dSSc than in lSSc patients (P < 0.05). Five of 8 single SF-36 domain scores were lower in SSc patients than in controls (P < 0.05). Vitality was higher in dSSc than in controls (P < 0.001). In SSc, elder age correlated with lower PSS; low ACE levels and high skin score correlated with higher general mental health and role limitations due to physical problems, respectively (P < 0.05). Patients with heart involvement had higher scores in general health perceptions (P < 0.05). CONCLUSION: The SF-36 shows that HRQOL is impaired in patients with SSc. Higher scores in MSS and vitality in patients with dSSc and correlations of high SF-36 scores with specific organ involvement suggest that SSc patients with severe disease are more able to cope with HRQOL modification.