Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Mononeuropathies”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources

Interleukin-6-mediated hyperalgesia/allodynia and increased spinal IL-6 expression in a rat mononeuropathy model.

It has been suggested that neuroimmunologic mechanisms may be involved in the development and maintenance of neuropathic pain. To further address this concept, the immunoreactive spinal expression of the pro-inflammatory cytokine, interleukin-6 (IL-6), was determined in the mononeuropathy model in the rat, sciatic cryoneurolysis (SCN). This well-established animal model expresses behaviors suggestive of neuropathic pain in humans. Immunohistochemical localization in the spinal cord was determined at 3, 7, 14, 21, 35, and 120 days after SCN (n = 6 per time point). Immunoreactive IL-6 increased incrementally in the substantia gelatinosa and motoneurons over time following SCN as compared with normal rats. In an additional study, recombinant human IL-6 was administered intrathecally to normal and previously SCN-lesioned rats. Intrathecal IL-6 produced touch-evoked allodynia (increased sensitivity to a nonnoxious stimulus) in normal rats and thermal hyperalgesia (increased sensitivity to a noxious stimulus) in previously lesioned SCN rats. These results provide evidence that IL-6 may be involved in the cascade of events leading to the development and maintenance of behaviors suggestive of neuropathic pain following peripheral nerve injury.

Analysis of Variance↗

Intrathecal and systemic R-phenylisopropyl-adenosine reduces scratching behaviour in a rat mononeuropathy model.

The aim of the present study was to investigate the effect of intravenous or intrathecal (i.t.) administration of R-phenylisopropyladenosine (R-PIA), a selective A1 adenosine receptor agonist, on spontaneous scratching behaviour, a phenomenon presumably related to pain in a mononeuropathy model (sciatic nerve ligation) in rats. The acute effect of daily i.t. R-PIA injections was studied up to 21 days following nerve ligation. The results demonstrate that both i.v. (30 nmol) and i.t. (3 nmol) R-PIA, in doses not producing any motor impairment, significantly reduces scratching behaviour in this animal model. The mechanism of action for this presumed antinociceptive effect is suggested to occur at the spinal cord level.

Adenosine↗

Electromyographic motor Tinel's sign in ulnar mononeuropathies at the elbow.

A novel test for localizing ulnar mononeuropathies (UM), the electromyographic (EMG) motor Tinel's sign, has been developed. While recording with a monopolar needle from the abductor digiti minimi, the ulnar nerve is lightly rolled at multiple sites across the elbow, and the test is considered positive if a burst of EMG activity is observed simultaneously with nerve compression. To determine the use of the EMG Tinel's sign, we evaluated 70 control nerves and 50 clinically suspected UMs. The EMG Tinel's sign had a 78% sensitivity and a 79% specificity for suspected UM at the elbow. The clinical Tinel's sign was present in 68% of suspected UM cases, and the combined sensitivity of the EMG and clinical Tinel's sign was 96%. Using nerve conduction study (NCS) values derived from the control nerves, 62% of UM nerves had abnormal NCS/EMG findings, and 28% of UM nerves had NCS/EMG abnormalities that could be localized to the elbow. The development of motor axon mechanosensitivity at the site of nerve injury is a new finding, not previously observed in electrophysiologic studies of animal nerve injury models or reported in the electrodiagnostic literature.

Action Potentials↗

Outcome of implanted spinal cord stimulation in the treatment of chronic pain: arachnoiditis versus single nerve root injury and mononeuropathy. Brief clinical note.

Over a 3 1/2-year period, a series of 20 chronic pain patients with back pain and with documented organic difficulties were treated by means of implanted spinal cord stimulation. Short-term treatment outcome was found to be significantly related to diagnosis, with single nerve root injury and mononeuropathy patients having better treatment outcomes than arachnoiditis patients with multiply injured nerve roots. Outcome was not related to the psychological evaluation, or age, sex, number of previous pain surgeries, pain location, the Minnesota Multiphasic Personality Inventory, or the Pain Assessment Index. Implications for patient selection are discussed.

Adult↗

Cigarette smoking and ulnar mononeuropathy at the elbow.

OBJECTIVE: To identify lifestyle risk factors for electrodiagnostically confirmed ulnar mononeuropathy at the elbow (UME). DESIGN: A case-control study involving 101 subjects (12 with definite UME, 42 with probable UME, and 47 controls) who responded to a questionnaire requesting information on subject vocation, repetitive upper limb activity, and alcohol and cigarette use. RESULTS: Subjects with definite UME reported greater tobacco usage as defined by cigarettes per day (mean +/- standard error; 20.1 +/- 5.2, 9.3 +/- 1.9, 8.6 +/- 1.5 cigarettes/day for definite, probable UME, and controls, respectively; P = 0.014) and pack-years (27.3 +/- 9.7, 12.5 +/- 3.0, 9.9 +/- 2.3, for definite, probable UME, and controls, respectively; P = 0.029). The association between cigarettes and definite UME persisted after adjustment for age, sex, and body mass index and was not confounded by alcohol use. Significant negative correlations between tobacco use and ulnar conduction velocities across the elbow and amplitudes above the elbow were identified. CONCLUSIONS: Cigarette smoking and UME seem to be associated. The presence of a plausible mechanism for injury and a dose-response effect suggests that this association may be causative.

Adult↗

Treatment concepts for idiopathic and iatrogenic femoral nerve mononeuropathy.

Femoral mononeuropathy has many etiologies and is often quite disabling, causing lower extremity paresthesia, anesthesia, pain, or paresis. Despite its morbidity, few therapies have been described to treat the femoral nerve palsy that does not resolve with conservative management or that is refractory to physical therapy. In this report, we present 3 cases of femoral nerve palsy; one as a complication of local nerve block, one as a complication of laparotomy, and one of idiopathic origin. In each case, symptomatic and objective improvement was achieved with femoral neurolysis. We suggest guidelines for the management of those patients who fail to respond to conservative therapy and indications for surgical intervention.

Adult↗

Multicenter study of peroneal mononeuropathy: clinical, neurophysiologic, and quality of life assessment.

This is a multicenter study on peroneal mononeuropathy (PM), in which a multidimensional protocol was performed to evaluate (1) the predisposing factors and their occurrence; (2) the relationships between the etiological, clinical, and neurophysiologic findings; and (3) disability and quality of life (QoL) in a wide sample with PM. Clinical and neurophysiologic evaluation was performed in all patients; moreover, the group adopted validated disability and QoL measurements to obtain more comprehensive and reliable data on PM. From November 2002 to January 2004, 69 patients were enrolled consecutively in 11 Italian centers. Our data showed that PM involves men more frequently than women (male : female = 4.1:1). PM was idiopathic (16%) or due to prolonged posture (23.1%), surgery (20.3%), weight loss (14.5%), trauma (11.6%), bedridden condition (7.3%), external compression from cast (5.8%), and arthrogenic cyst at the fibula (1.4%). Unexpectedly, peroneal nerve lesions were not only due to surgical operation close to the peroneal region but were also associated with thoracic-abdominal surgery. We observed conduction block in about 50-70% of postural and weight loss PM; in perioperative and idiopathic PM, conduction block or mixed damage was equally present; in PM due to trauma, we observed an exclusive axonal damage in about 60% of cases. Only in three cases (one postural PM, one idiopathic PM, and one weight loss PM), we observed a slowing of conduction velocity in the popliteal fossa-fibular head segment without conduction block. The comparison between QoL in patients with PM and in healthy subjects showed a significant involvement of physical and mental aspects. With regard to disability, 68% of patients walked with difficulty. Our data show that (1) most of the cases of PM are due to an identifiable predisposing factor; (2) there is a good correlation between predisposing factors and clinical-neurophysiologic findings; and (3) PM causes disability and deterioration of the physical and emotional aspects of QoL.

Adult↗

Hypertrophic mononeuropathy.

A case of hypertrophic mononeuropathy is described in a 19-year-old female. The entity is very rare as only three previous cases have been reported. The light and electron-microscope appearances resemble those of progressive hypertrophic polyneuritis.

Adult↗

Concurrent Bell's palsy and diabetes mellitus: a diabetic mononeuropathy?

In a series of 126 patients with Bell's palsy, chemical or overt diabetes mellitus was found in 39% of the cases. A high frequency of disturbances of taste was found in the patients who had no diabetes (83%), as compared to only 14% of diabetic patients whose taste was affected (p less than 0 .001). Thus, the usual site of facial nerve lesion in diabetics appears to be distal to the chorda tympani, while in patients whose glucose tolerance is normal, no such selectivity exists. This may only be explained by a diabetes-related pathogenesis and a vascular rather than a generalised "metabolic" impairment is postulated, leading to a localised facial nerve ischaemia in the distal part of the Fallopian canal. Thus, some cases of Bell's palsy may in fact be a diabetic mononeuropathy.

Diabetic Neuropathies↗

Neuronal responsiveness in the ventrobasal thalamic complex of rats with an experimental peripheral mononeuropathy.

1. Single-unit recordings were made, under moderate gaseous anesthesia (33% O2-66% N2O + 0.5/0.6% halothane), in the ventrobasal (VB) thalamic complex of rats (n = 42) with a mononeuropathy created 2-3 wk beforehand, by four loose ligatures around the common sciatic nerve. Before the recording session, three behavioral nociceptive tests to both mechanical and thermal stimuli revealed that these rats exhibited clear hyperalgesia (excessive reactions to noxious stimuli) and allodynia (nociceptive reactions to stimuli usually perceived as nonnoxious). 2. Neurons, characterized by their responses to manual mechanical stimuli, were classified into two groups: group 1 neurons exclusively driven by light tactile stimuli applied to the receptive field (RF), strictly contralateral to the recording site; and group 2 neurons, driven by sustained pinch applied to a large RF, often bilateral. 3. From the total population of neurons (n = 386), only those responding to stimuli applied to one posterior paw were studied; the proportion (35-40%) of these cells was comparable in each of the two VB: n = 93/262 and 44/124 in the VB contralateral (VBc) and ipsilateral (VBi) to the damaged nerve, respectively. The proportions of each functional group of neurons (group 1 or 2) were also similar on each side. 4. For all group 1 neurons the RFs size was comparable to that observed in normal rats. In the VBi the responses of these neurons presented the classical response pattern observed for VB neurons involved in touch transmission, as did the VBc group 1 neurons with RFs in the saphenous (Sa) territory. In sharp contrast, activities of VBc group 1 neurons with RFs in the sciatic (Sc) nerve territory exhibited several abnormalities: higher background activity, fading of the response with repetitive stimulation, and afterdischarges outlasting the applied stimulus. 5. As in normal rats, 52% of VB group 2 neurons exhibited bilateral symmetrical RFs. Their responses to mechanical stimuli were often greater for stimuli applied to the affected paw, and some of them could be activated by moderate pressure to this paw. Heat responses also illustrated the profound increased sensitivity of the lesioned side, and the activation threshold to thermal stimulation of these group 2 neurons was lowered by 4-6 degrees C compared to normal values. In addition, these neurons responded to immersion of the lesioned paw in a 10 degrees C water bath, a stimulus that was ineffective when applied to the opposite paw.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Mononeuropathy multiplex as a complication of amphetamine angiitis.

A patient who abused multiple drugs developed a rapidly progressive mononeuropathy multiplex, which appeared to respond to corticosteroid therapy with partial resolution. Intravenous methamphetamine had been used almost exclusively from the fourth month prior to the onset of symptoms. Biopsy material revealed a necrotizing angiitis involving medium and small sized arteries, capillaries, and venules, typical of a hypersensitivity-type angiopathy, rather than the previously reported polyarteritis nodosa-type lesions secondary to illicit drugs. The apparent response to corticosteroids suggests that these agents might be useful in the treatment of some complications of drug abuse.

Adolescent↗

Mononeuropathy due to vincristine toxicity.

Vincristine sulfate is a known neurotoxin. Peripheral neuropathy is the most common toxic manifestation and is usually of the symmetrical, mixed, sensory-motor type. With this report we alert other physicians to another feature of vincristine neurotoxicity, namely, mononeuropathy.

Child, Preschool↗

Sciatic endometriosis: a treatable sensorimotor mononeuropathy.

Sciatic endometriosis may cause cyclic sciatic pain and a sensorimotor mononeuropathy. Neurophysiologic tests and conventional radiologic examinations are of little value in delineating this lesion, but the pelvic CT appearance of sciatic endometriosis is distinctive. Suppression of the ovarian cycle and surgical removal of endometriosis and adhesions from in and around the sciatic nerve usually relieve the pain and stabilize neurologic function.

Adult↗

Common peroneal mononeuropathy: a clinical and electrophysiologic study of 116 lesions.

We analyzed the clinical and electromyographic (EMG) findings of 116 common peroneal mononeuropathies in 103 patients (13 with bilateral lesions). Prior to the EMG examination, the diagnosis was not clinically suspected or seriously considered in 44% of the lesions. Sensory manifestations were common (79%) but pain was rare (16.5%). The onset was acute in 57 patients, gradual in 35, and indeterminate in 11. Of the 116 lesions, 64 were solely axonal loss in type, 23 manifested as conduction block, presumably secondary to focal demyelination, and 29 were a mixture of the two. Contrary to common belief, the pathophysiology was predominantly axonal loss regardless of etiology, including those that developed perioperatively. The peroneal motor nerve conduction study, recording tibialis anterior muscle, was the single most important electrophysiologic study; it localized all 52 lesions causing conduction block at the fibular head. In contrast, peroneal motor conduction velocity along the knee-to-fibular head segment was seldom abnormal, with slowing in only five of the 52 cases.

Action Potentials↗

Localized hypertrophic mononeuropathy involving the femoral nerve.

The authors report a case of localized hypertrophic mononeuropathy involving the femoral nerve in a 20-year-old woman referred because of progressive weakness and atrophy of the left thigh. MRI showed an enlarged femoral nerve and biopsies of fascicles displayed a concentric pattern of cells resembling an onion bulb. These cells were positive for epithelial membrane antigen immunostaining and had an incomplete basal lamina.

Adipose Tissue↗