Irene Aprile

Carpal tunnel syndrome modifies sensory hand cortical somatotopy: A MEG study

The adult somatosensory system has shown reorganizational abilities at cortical and subcortical levels after peripheral nerve lesions. In the present study the effects of carpal tunnel syndrome (CTS) are investigated as reflected on the somatotopy of the primary cortical hand representation. Position and intensity of cortical sources activated by the separate electrical stimulation of median nerve and Digits 1, 3, and 5 of both affected and non‐affected hands are evaluated by magnetoencephalographic (MEG) technique. Correlation of MEG results with patient‐, physician‐ and neurophysiological‐oriented evaluations of CTS was carried out. Patients showed changes in cortical hand somatotopy in strict relationship to self‐referred assessment of symptoms and hand disability in daily activities, including: 1) a more extended representation of the affected hand when paresthesias prevailed; and 2) a more restricted representation due to lateral shift of the little finger was observed when pain symptoms dominated the clinical picture. Contralateral to the side of CTS, the cortical sources activated by Digit 5‐stimulation appeared significantly enhanced with respect to contralateral ones from non‐affected hand. When comparing the amplitude of peripheral sensory nerve action potentials of median and ulnar nerves to that of cortical responses (i.e., ECD strengths of M20 and M30 components after stimulation of Digits 3 and 5), a significant selective amplification of M30 with respect to M20 and sensory nerve action potential (SNAP) appeared during Digit 3 stimulation compared to that observed for Digit 5. This has been interpreted as a central magnification mechanism in brain responsiveness, possibly revealing a safety factor enabling sensory perception despite the small peripheral signal due to nerve trunk dysfunction. Hum. Brain Mapping 17:28–36, 2002.

A systematic review of conservative treatment of carpal tunnel syndrome

Objective : To assess the effectiveness of conservative therapy in carpal tunnel syndrome. Data sources : A computer-aided search of MEDLINE and the Cochrane Collaboration was conducted for randomized controlled trials (RCTs) from January 1985 to May 2006. Review methods : RCTs were included if: (1) the patients, with clinically and electrophysiologically confirmed carpal tunnel syndrome, had not previously undergone surgical release, (2) the efficacy of one or more conservative treatment options was evaluated, (3) the study was designed as a randomized controlled trial. Two reviewers independently selected the studies and performed data extraction using a standardized form. In order to assess the methodological quality, the criteria list of the Cochrane Back Review Group for systematic reviews was applied. The different treatment methods were grouped (local injections, oral therapies, physical therapies, therapeutic exercises and splints). Results : Thirty-three RCTs were included in the review. The studies were analysed to determine the strength of the available evidence for the efficacy of the treatment. Our review shows that: (1) locally injected steroids produce a significant but temporary improvement, (2) vitamin B6 is ineffective, (3) steroids are better than non-steroidal anti-inflammatory drugs (NSAIDs) and diuretics, but they can produce side-effects, (4) ultrasound is effective while laser therapy shows variable results, (5) exercise therapy is not effective, (6) splints are effective, especially if used full-time. Conclusion : There is: (1) strong evidence (level 1) on efficacy of local and oral steroids; (2) moderate evidence (level 2) that vitamin B6 is ineffective and splints are effective and (3) limited or conflicting evidence (level 3) that NSAIDs, diuretics, yoga, laser and ultrasound are effective whereas exercise therapy and botulinum toxin B injection are ineffective.

Contribution of ultrasound in a neurophysiological lab in diagnosing nerve impairment: A one-year systematic assessment

OBJECTIVE To evaluate the usefulness of a combination of electromyography (EMG) and ultrasound (US) assessments in diagnosing nerve trunk involvement. We hypothesised that in some cases, when the clinical or neurophysiological picture is unclear, the simultaneous study of the peripheral nervous system through both US and EMG may provide pathologic information not obtainable through EMG alone, and this may influence therapeutic decisions. METHODS In 2005, we performed a prospective study in 77 consecutive patients with involvement of a single nerve trunk, using a combination of EMG and US in the same session. We divided the diagnostic contribution of US into four categories: diagnostic, confirming, inconclusive and misdiagnostic. RESULTS In about a quarter of the patients, US provided results confirming the clinical neurophysiological diagnosis. In another quarter of the cases, US was very helpful in modifying diagnosis and therapy. In most of these cases, the contribution of US was important for the detection of tumors or cysts, thus showing the cause of nerve involvement. In half of the cases the US results were inconclusive, and in one case US was misdiagnostic. CONCLUSIONS The combination of EMG and US performed in the same session (or in collaboration with an ultrasound examiner) may be useful for diagnosis and determination of appropriate therapy. SIGNIFICANCE Diagnosis of mononeuropathies is improved through a combined functional and morphological evaluation of the nerve by using EMG and US.

Symptoms and neurophysiological picture of carpal tunnel syndrome in pregnancy

OBJECTIVE To evaluate the incidence of carpal tunnel syndrome (CTS) in pregnancy through a validated and multiperspective assessment of CTS. METHODS During 2000, the Italian CTS study group focussed on the occurrence of CTS in women during the final stages of pregnancy, enrolled in 7 Italian centers. In addition to the physician-centered and neurophysiologic traditional evaluations, we used a validated patient-oriented measurement to obtain more comprehensive and consistent data for severity of symptoms and functional impairment. RESULTS In our study, CTS was clinically diagnosed in more than half of women (62%). Neurophysiological evaluation provided diagnosis of CTS in around half of women (43% were positive in one hand at least). Our study provides evidence, reported here for the first time, of a correlation between edema and neurophysiological picture. Similarly, our study provides a correlation between validated patient-oriented measurement and edema. Moreover, a significant correlation between a negative trend (subjectively assessed) and smoking and alcohol consumption was observed. CONCLUSIONS Our observations confirm that the edema of the tissues in the carpal tunnel could induce a mechanical compression of the nerve. Moreover, our data suggest that smoking and alcohol consumption have a negative role in the evolution of the syndrome probably due to impairment of the microcirculation.

Seronegative myasthenia gravis: comparison of neurophysiological picture in MuSK+ and MuSK− patients

The aim of this study was to compare the neurophysiological and clinical pictures of a large sample of seronegative myasthenia gravis (SNMG) patients with and without anti‐MuSK antibodies. Fifty‐two consecutive SNMG patients were retrospectively evaluated. They had undergone an extended neurophysiological evaluation: repetitive nerve stimulation (RNS), single fiber EMG (SFEMG), and electromyography (EMG) with nerve conduction study. A muscle biopsy was performed in 11 of 52 patients, the edrophonium test in 44 of 52 patients and anti‐AChR antibodies and anti‐MuSK antibodies were tested in all patients. Anti‐MuSK antibodies were detected in 25 SNMG patients (48.1%). The number of women in the MuSK+ group was significantly higher (P = 0.01) than in the MuSK− group. Seronegative MuSK+ patients are more severely affected and the deficit often involves the bulbar and the respiratory muscles. No statistically significant differences were observed in the edrophonium test between MuSK+ and MuSK− groups. The RNS test was abnormal in a significantly higher number of MUSK− patients than MUSK+ patients (P < 0.00001). With regard to SFEMG data, MuSK− patients were characterized to have more severe neurophysiological pattern. Our observations showed several differences between the clinical and neurophysiological pictures of MUSK+ and MUSK− patients.

Distribution of paresthesias in Carpal Tunnel Syndrome reflects the degree of nerve damage at wrist

OBJECTIVE To verify whether the distribution of paresthesias in patients with Carpal Tunnel Syndrome (CTS) is related to the degree of the neurophysiological involvement. METHODS We performed a cross-sectional study and retrospectively evaluated 163 patients who referred to our electromyography lab and to which a clinical and electrophysiological diagnosis of CTS was made. We divided the patients into two groups: (1) patients complaining of paresthesias at the hand as a whole and (2) patients with paresthesias in the territory of the median nerve. We referred to the distribution of paresthesias at the hand as GLOVE and to the distribution in the territory of the median nerve as MEDIAN. We compared the neurophysiological impairment in GLOVE and MEDIAN distributions. Moreover, we performed multiple regression analysis to evaluate which clinical-neurophysiological variables determined GLOVE and MEDIAN distribution. RESULTS In our sample, 70.4% of patients had GLOVE distribution and 29.6% of patients MEDIAN distribution. The risk of presenting MEDIAN distribution increases about twice (OR = 2.07; 95% IC: 1.51-2.83) for each unitary increment of neurophysiological class. CONCLUSIONS The distribution of paresthesias reflects the degree of nerve damage at wrist; patients suffering of SEV/EXT CTS present MEDIAN distribution. SIGNIFICANCE Our data have important clinical implications because they strongly suggest that we have to consider the possibility of a severe neurophysiological involvement of the median nerve at wrist in patients complaining of MEDIAN distribution.

Peroneal mononeuropathy: predisposing factors, and clinical and neurophysiological relationships.

Abstract The most common mononeuropathy in the lower extremity involves the nerve. We retrospectively evaluated the etiological predisposing factors and clinical-neurophysiological features of 36 patients affected by peroneal mononeuropathy (PM). In 30 patients, a clear predisposing factor was identified. PM was more frequently perioperative (11 cases), associated with axonal involvement. Unexpectedly, PM was not only due to surgery close to the peroneal region, but was mostly associated with hip surgery and, rarely, with thoracic-abdominal surgery. A postural predisposing factor of PM was also frequently observed, usually associated with a pure conduction block. Conversely, most patients with bedridden predisposing factor presented axonal involvement, which was rarely associated with conduction block. In 25 of 36 PM cases, a long-term follow-up lead to an improvement (12 cases) or to good recovery (13 cases) of PM. In conclusion, our study shows that: (1) in most PM cases it is possible to identify a predisposing factor; (2) there is a good correlation between predisposing factor and neurophysiological involvement, and (3) PM usually has usually a good prognosis.

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

Abstract  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.

Myasthenia gravis outcome measure: development and validation of a disease-specific self-administered questionnaire

Abstract. We describe the development and validation of an outcome measure for patients with myasthenia gravis (MG) and show the correlation of the items with conventional MG measurements. In stage I, item generation, a group of methodologists, clinical experts generated a list of 56 items. The list was based on (1) a previous study on an MG sample, (2) clinical experience and (3) items proposed by MG patients. In stage 2, reduction of items, the list was reduced on the basis of results from field testing (41 patients completed the 56-item questionnaire). In stage 3, reliability and validity were assessed. A 25-item MG questionnaire (MGQ) was generated. Results were related to conventional measures of MG severity. Furthermore, the MGQ appeared reliable, sensitive and reproducible. The questionnaire was validated as an outcome measure.

QUALITY OF LIFE AND PAIN IN PATIENTS WITH FACIOSCAPULOHUMERAL MUSCULAR DYSTROPHY

The aim of this study was to assess quality of life (QoL) and evaluate the occurrence and characteristics of pain in facioscapulohumeral muscular dystrophy (FSHD) patients. No study has yet assessed QoL in a large group of FSHD patients and, overall, few studies have assessed pain in neuromuscular diseases. We performed a prospective study using a multidimensional protocol including: clinical (according to the Clinical Severity Scale Rev1); genetic (p13E‐11 EcoRI fragments Rev1); QoL (Short Form‐36); pain (Visual Analog Scale and Portenoy‐6 questions); and depression (Beck Depression Inventory) assessment. QoL measures of FSHD were compared with those of Italian norms. Moreover, we correlated QoL and pain measurements with clinical findings. Sixty‐five patients were enrolled in the study. QoL was statistically significantly reduced with respect to the Italian normative sample, mainly in physical domains. Our study demonstrated that pain is frequent in FSHD patients. More than half of the patients complained of at least moderate pain. Women complained of slightly higher levels of deterioration in the emotional aspects of QoL than men. Clinical pattern (as assessed by Clinical Severity Scale) was closely related to physical QoL domains: the higher the clinical involvement, the more severe the QoL deterioration. This study provided information that may be crucial in clinical practice: pain may be a relevant aspect in FSHD patients, and prevention strategies or relevant therapies should be considered as appropriate. Moreover, we must pay more attention to gender differences: women can suffer far greater deterioration in the emotional aspects of QoL. Further multidimensional observations are needed. Muscle Nerve 40: 200–205, 2009