Electromyographic analysis of the results given by lumbar discal herniation treatment with intradiscal oxygen-ozone gas mixture injection.

Among patients treated by intradiscal oxygen-ozone administration, in the period from January to June 18, because of disco radicular conflict, we randomly selected a group of 200 cases for this study. The classical instrument for studying nerve functioning alteration is EMGraphy. Repeated EMGraphic control during the treatment gives a valid parameter to quantify nerve root dysfunction: this is objective, repeatable and is precise data. The evolution of EMGraphic picture does not always correspond to the clinical situation. In several cases the normalization of the last radicular conflict will coexist with residual signs of EMGraphic dysfunction.

Schwannoma of median nerve at the elbow. Case report and short review of the literature.

The Authors present a case of rare elbow localization of schwannoma of the median nerve, in 42 year old woman. The surgical treatment and the short follow-up are presented.

Considerations on the treatment of anterior interosseous nerve syndrome.

Anterior interosseous syndrome (Kiloh-Nevin syndrome) refers to that constellation of signs and symptoms referable to weakness of the pronator quadratus, the flexor pollicis longus, and the flexor digitorum profundus to the index finger.We present our series of 9 patients, affected by AIN Syndrome, and a group of 4 patients affected by pseudo-AIN neuropathies.In the literature there is considerable controversy concerning the treatment, but we agree that understanding of anatomical variants of innervation combined with a thorough physical examination can provide important clues as to where pathology resides. Proper treatment needs a precise and accurate diagnosis; in fact medical treatment which we present is effective for nerve dysfunction and may avoid surgery, but surgical exploration is mandatory when EMG is suggestive of a severe lesion, and localizes the specific site on anterior interosseous nerve entrapment.

Chronic subdural hematoma: comparison of two surgical techniques. Preliminary results of a prospective randomized study.

AIM: The optimal treatment for chronic subdural hematoma (CSDH) is not yet well defined and research for efficient surgical solutions continues. Burr hole craniotomy (BHC) is a common treatment and twist drill craniostomy (TDC) is a less invasive alternative. A closed-system drainage with subdural expansion catheter and suction reservoir can be used to enhance the TDC procedure. METHODS: We report preliminary results of a prospective study comparing BHC and TDC with suction drainage, in a series of 47 patients randomized into two treatment groups. One group of 22 patients underwent TDC with closed-system drainage and suction reservoir (14 men, 8 women, mean age 78.7 years). Another group of 24 patients underwent BHC with subdural irrigation and closed drainage (16 men, 8 women, mean age 76.3 years). Neurological status was assessed by Markwalder's Grading Scale on admission and at follow-up. All patients underwent computed tomography (CT) before surgery, within 4 days after it, and 1 and 2 months later. RESULTS: Preoperative clinical and radiological data were similar in the two groups. Operating times were shorter in the TDC group, while drainage time was shorter in the BHC group (P<0.0001). Length of hospitalization was similar. Recurrence rate, mortality, and neurological recovery were similar, with non significant differences in favor of the TDC group. After 2 months, CT showed complete regression of subdural effusion in 66.6% of cases in the TDC group and in 31.8% in the BHC group (P<0.05). CONCLUSIONS: Preliminary results indicate TDC and BHC as at least equally effective, however TDC favors faster regression of residual subdural effusion, is a faster procedure, and seems to be associated with fewer recurrences. If confirmed at the end of the study, these results could indicate TDC with suction as the elective surgical treatment for CSDH.

Wrist median nerve motor conduction after end range repeated flexion and extension passive movements in Carpal Tunnel Syndrome. Pilot study.

Carpal Tunnel Syndrome (CTS) can be due to a variety of different pathological conditions. These etiological and epidemiological differences may explain the non-homogeneous response to ordinary conservative therapeutical options observed in this syndrome. The aim of our study was to investigate on the possibility of identifying different sub-groups of patients among conservatively treatable CTS with different susceptibility to physiotherapeutic treatments. We decided to utilize an objective approach measuring some median motor nerve function parameters. Short term variations of Compound Motor Action Potential (CMAP) from the thenar eminence were compared in two groups of 55 hands (CTS patients and normal controls) after performance of two different types of end range passive movement. We found a different distribution of CMAP amplitude modifications within a sub-group of patients that suddenly improved more than the controls after two series of 10 end range passive flexions or after two series of ten end range passive extensions. Amplitude changes proved to be much more useful than latency variation studies in the provocative test neurophysiological approach. The method we propose appears to be useful for better surgical indication and/or for improvement of conservative therapeutic choice.

Preliminary results of a soft novel lumbar intervertebral prothesis (DIAM) in the degenerative spinal pathology.

The authors report a series of 43 patients suffering from lower limb pain, almost constantly associated with chronic or acute backpain, treated by microsurgical nerve root decompression and by implantation of a soft intervertebral prothesis (DIAM). Satisfying results were obtained in 97% of cases, inducing the authors to consider the device a reliable tool for curing low-back pain and sciatica. Selection criteria are exposed and discussed.

Operative results without invasive monitoring in patients with frontal lobe epileptogenic lesions.

PURPOSE: To further explore the still controversial issues regarding whether all or most candidates for epilepsy surgery should be investigated preoperatively with invasive long-term video-EEG monitoring techniques (ILTVE). METHODS: We studied five patients with intractable seizures since early childhood using the same protocol: clinical evaluation, magnetic resonance imaging (MRI) with fluid-attenuated inversion recovery (FLAIR) sequences, long-term video-EEG (LTVE) monitoring with scalp electroencephalogram (EEG), interictal single photon emission computed tomography (SPECT), positron emission tomography (PET), and neuropsychological testing. The patients' seizures had clinical features suggesting a frontal lobe (FL) origin. MRI scans revealed focal cortical dysplasia (CD) in four patients and a probable gliotic lesion in the fifth. The findings in both PET and SPECT images were congruent with those of the MRI. Scalp LTVE failed to localize the ictal onset, although the data exhibited features suggestive of both CDs and FL seizures. On the basis of these results, surgery was performed with intraoperative corticography, and the cortical area exhibiting the greatest degree of spiking was ablated. RESULTS: Histopathologic study of four of the resected specimens confirmed the presence of CD, whereas in the fifth, there were features consistent with a remote encephaloclastic lesion. There were no postoperative deficits. Seizures in three of the patients were completely controlled at 2-3.5 years of follow-up; a fourth patient is still having a few seizures, which have required reinstitution of pharmacotherapy, and the fifth has obtained > or =70% control. All patients have had significant improvement in psychosocial measures. For comparison, five patients with generally similar clinical and neuroradiologic features to the previous group underwent preoperative ILTVE monitoring. The surgical outcomes between the two groups have not differed significantly. CONCLUSIONS: We conclude that patients with FL epilepsies may be able to undergo successful surgery without preoperative ILTVE monitoring, provided there is high concordance between neuroimaging tests (MRI, SPECT, PET) and the seizure phenotypes, even when routine EEGs and scalp LVTE fail to localize ictal onset unambiguously. The surgical outcomes of these patients generally paralleled those of the other subjects who also had FL epilepsy but who were operated on only after standard ILTVE monitoring.

The importance of surgery in supratentorial ependymomas. Long-term survival in a series of 23 cases.

In view of the widely recognized correlation between extent of surgical resection and length of survival of children with intracranial ependymoma and the statement that total resection is more likely to be achieved in supratentorial than infratentorial primaries, we decided to review our experience with supratentorial ependymomas and the pertinent literature to verify the importance of surgery in treating this subgroup of pediatric ependymal neoplasms. Of 23 patients operated on, 12 are still alive without evidence of disease 72-357 months after surgery (mean 227, median 237 months). One girl treated by surgery alone was lost to follow-up after 234 months when she, and 7 other patients in the series, had already passed the end of the period of risk for recurrence according to Collins' law. Six surviving patients (2 with subependymoma and 4 with ependymoma) were treated by surgery alone and only 1, the oldest in the series, had to undergo a second operation for recurrence after 10 years. The idea of treating intracranial ependymoma by surgery alone was favored by eminent neurosurgeons in the past and has recently received renewed attention. This was in part the consequence of recognizing that unlike diffuse astrocytoma, in which neoplastic cells can be found up to several centimeters away from the apparent tumor borders, ependymoma has more or less well-defined margins and grows mainly by expansion. Early experience with the policy of electively deferring adjuvant therapy after radiologically controlled total resection of ependymoma seems encouraging, although postoperative MRI does not yet indicate absolute certainty. Close surveillance is recommended. The majority of ependymomas so far treated by surgery alone, with relatively good success, have been supratentorial. In conclusion, on the basis of our experience and a review of the literature we favor a change in attitude to the management of intracranial ependymomas, especially of the cerebrum, with radiologically controlled radical surgery alone followed by close surveillance with periodic MR imaging until the child passes the period of risk for recurrence according to Collins' law as the initial option. In children less than 3 years old the period of surveillance should be doubled. In case of recurrence, reoperation should be considered first, particularly for supratentorial primaries. Radiotherapy continues to be a major option in malignant ependymoma and unresectable primary or recurrent benign ependymoma.

Spinal reflex pattern to foot nociceptive stimulation in standing humans.

Ipsi- and contralateral patterns of lower limb nociceptive reflex responses were studied in 6 normal subjects in free standing position. Once the position was stabilized, only ankle extensor muscles showed consistent tonic activity while ankle flexors and knee extensors and flexors were virtually silent. Reflex responses, elicited by painful electrical stimuli to the skin of the plantar and dorsal aspect of the foot, were recorded from ipsi- and contralateral quadriceps (Q), biceps femoris (Bic), tibialis anterior (TA) and soleus (Sol) muscles. Plantar foot stimulation evoked a large excitatory response in the ipsilateral TA at about 80 ms and a smaller responses in Bic and Q at 70 ms and 110 ms, respectively. Ipsilateral excitatory effects after dorsal foot stimulation consisted of a Bic response at about 75 ms. In addition to excitatory effects, both plantar and dorsal foot stimulation evoked long-lasting suppression of ipsilateral Sol background activity starting at about 60 ms. Contralaterally, the only nociceptive effects after plantar or dorsal foot stimulation were a small excitatory response of Sol at about 85 ms. Evidence is provided that only excitatory responses were contingent upon nociceptive volley. The main mechanical effects seen after plantar stimulation were dorsiflexion of the foot without loss of heel contact with the floor; no withdrawal response of the foot followed nociceptive dorsal stimulation. Our main conclusion is that only reflex nociceptive responses serving to avoid the stimulus without conflicting with limb support function are expressed. The mechanisms reconciling nociceptive action and postural function of the lower limbs are discussed.

Carpal tunnel syndrome in amyotrophic lateral sclerosis and late onset cerebellar ataxia.

We report on clinical and electrophysiological findings and management in nine patients who developed carpal tunnel syndrome during the course of amyotrophic lateral sclerosis and late onset cerebellar ataxia, two neurodegenerative diseases. The patients were treated with surgical decompression (five cases) and local steroid injections (four cases). Only one showed lasting relief of symptoms and significantly improved distal conduction in the median nerve at follow-up after 2 to 3 months. The symptoms and conduction data remained unchanged in three patients who could be followed for more than 1 year. We think that axonal neuropathy plays an important role in the development of carpal tunnel syndrome in these patients and accounts for the failure of the standard treatments.

Interaction of nociceptive and non-nociceptive cutaneous afferents from foot sole in common reflex pathways to tibialis anterior motoneurones in humans.

In six healthy subjects, the reflex responses of the tibialis anterior muscle (TA) to stimulation of the cutaneous afferents arising from plantar foot, were studied at rest and during different levels of steady voluntary contraction of the TA. At rest, the threshold of the response and the threshold of subjective pain sensation coincided. The mean latency of this TA nociceptive response was 84.7 ms. Steady voluntary contractions of the TA, which was increased progressively from 3% to 15% of the maximum voluntary contraction, produced a significant and parallel reduction in the threshold and latency of the response: at 15%, the mean latency was about 26 ms shorter than at rest and its threshold was about half (i.e. below the pain threshold). The conduction velocity of the afferents responsible for TA response at rest was within the range of A-delta pain afferents (mean 27.4 m/s), whereas during voluntary contraction it was within the A-beta fibre range (mean 45.1 m/s). This suggests that descending command makes the discharge of low-threshold, fast-conducting fibres sufficient for reflex activation of TA motoneurones (MNs). Central delay (about 4 ms) and MN recruitment order (according to the size principle) were found to be the same for both nociceptive and non-nociceptive TA reflex responses. Finally, experiments of spatial summation revealed an interaction between nociceptive and non-nociceptive inputs at a premotoneuronal level. It is therefore proposed that nociceptive and non-nociceptive cutaneous afferents arising from the foot sole use the same short-latency spinal pathway to contact TA MNs and that their relative contribution to its segmental activation is contingent upon descending command.

Group Ia non-reciprocal inhibition from wrist extensor to flexor motoneurones in humans.

Interneurones mediating disynaptic inhibition from extensor to flexor carpi radialis muscles were characterized by pharmacological stimulation of Renshaw cells. It is, indeed, known that only Ia interneurones are blocked by recurrent inhibition. Renshaw cell potentiation, induced by intravenous administration of 2 g levo-acetylcarnitine, blocked Ia reciprocal inhibition from triceps to biceps muscles but not disynaptic inhibition from extensor to flexor carpi radialis muscles. It is concluded that the interneurones mediating this latter inhibition are not Ia interneurones. This kind of inhibition could be an example of a Ia non-reciprocal inhibitory pathway.

Heteronymous recurrent inhibition from gastrocnemius muscle to soleus motoneurones in humans.

Presence of heteronymous recurrent inhibition in motoneurones (Mns) innervating the soleus muscle (Sol) was investigated following electrical stimulation of the nerve of gastrocnemius medialis muscle (GM). Sub-threshold electrical stimulation for alpha Mns produced short-lasting inhibition of the Sol, reflecting non-reciprocal group I inhibition. After increasing the intensity of stimulation above the motor threshold, a short-latency, long-lasting inhibition appeared superimposed on the group I inhibition. Its amount increased with the size of the conditioning motor response and after acute administration of L-acetylcarnitine. It is concluded that this long-lasting inhibition of the Sol Mns is due to the heteronymous activity of the GM-coupled Renshaw cells.