Is spinal cord stimulation safe? A review of 13 years of implantations and complications.

OBJECTIVE: The aim of this review was to evaluate the complications of spinal cord stimulation (SCS) for chronic pain. METHODS: This was a retrospective case series of 212 patients treated with SCS for chronic lower-limb neuropathic pain between March 2002 and February 2015 in a Reims academic hospital. All patients received a surgically implanted paddle-type electrode. Complications with this technique are here described and analyzed, and other treatment and preventative methods proposed. RESULTS: The major indication was 'failed back surgery syndrome', and 74 (35%) patients experienced complications, of which 57% were benign, while 42% required invasive treatment. Most frequent complications (n=22, 10%) were hardware malfunctions. There were two cases (0.9%) of postoperative neurological deficit and nine (4.2%) with postoperative infections. All patients received the appropriate treatment for their complication. CONCLUSION: Despite the presence of complications, SCS is still a safe technique, although careful patient selection and proper surgical technique can help to avoid major complications.

Security and reliability of CUSTOMBONE cranioplasties: A prospective multicentric study.

BACKGROUND: Repairing bone defects generated by craniectomy is a major therapeutic challenge in terms of bone consolidation as well as functional and cognitive recovery. Furthermore, these surgical procedures are often grafted with complications such as infections, breaches, displacements and rejections leading to failure and thus explantation of the prosthesis. OBJECTIVE: To evaluate cumulative explantation and infection rates following the implantation of a tailored cranioplasty CUSTOMBONE prosthesis made of porous hydroxyapatite. One hundred and ten consecutive patients requiring cranial reconstruction for a bone defect were prospectively included in a multicenter study constituted of 21 centres between December 2012 and July 2014. Follow-up lasted 2 years. RESULTS: Mean age of patients included in the study was 42±15 years old (y.o), composed mainly by men (57.27%). Explantations of the CUSTOMBONE prosthesis were performed in 13/110 (11.8%) patients, significantly due to infections: 9/13 (69.2%) (p<0.0001), with 2 (15.4%) implant fracture, 1 (7.7%) skin defect and 1 (7.7%) following the mobilization of the implant. Cumulative explantation rates were successively 4.6% (SD 2.0), 7.4% (SD 2.5), 9.4% (SD 2.8) and 11.8% (SD 2.9%) at 2, 6, 12 and 24 months. Infections were identified in 16/110 (14.5%): 8/16 (50%) superficial and 8/16 (50%) deep. None of the following elements, whether demographic characteristics, indications, size, location of the implant, redo surgery, co-morbidities or medical history, were statistically identified as risk factors for prosthesis explantation or infection. CONCLUSION: Our study provides relevant clinical evidence on the performance and safety of CUSTOMBONE prosthesis in cranial procedures. Complications that are difficulty incompressible mainly occur during the first 6 months, but can appear at a later stage (>1 year). Thus assiduous, regular and long-term surveillances are necessary.

The nuclear DICER-circular RNA complex drives the deregulation of the glioblastoma cell microRNAome.

The assortment of cellular microRNAs ("microRNAome") is a vital readout of cellular homeostasis, but the mechanisms that regulate the microRNAome are poorly understood. The microRNAome of glioblastoma is substantially down-regulated in comparison to the normal brain. Here, we find malfunction of the posttranscriptional maturation of the glioblastoma microRNAome and link it to aberrant nuclear localization of DICER, the major enzymatic complex responsible for microRNA maturation. Analysis of DICER's nuclear interactome reveals the presence of an RNA binding protein, RBM3, and of a circular RNA, circ2082, within the complex. Targeting of this complex by knockdown of circ2082 results in the restoration of cytosolic localization of DICER and widespread derepression of the microRNAome, leading to transcriptome-wide rearrangements that mitigate the tumorigenicity of glioblastoma cells in vitro and in vivo with correlation to favorable outcomes in patients with glioblastoma. These findings uncover the mechanistic foundation of microRNAome deregulation in malignant cells.

[Nocardia brain abscess: features, therapeutic strategies and outcome]. / Abcès cérébraux àNocardia: caractéristiques radiocliniques et prise en charge thérapeutique.

BACKGROUND AND PURPOSE: Nocardia species is an aerobic soil-saprophyte bacterium, responsible for rare opportunistic infections, mainly reported in immunocompromised patients. Nocardia brain abscess accounts for 1 to 2% of cerebral abscesses. Prognosis is poor. METHODS: We describe clinical, radiological and bacteriological findings along with therapeutic aspects for five patients and review the literature on Nocardia cerebral abscess. RESULTS: The clinical features of Nocardia brain abscess are insidious and nonspecific, occurring frequently with a medical background of obvious or latent immunodeficiency; fever, if any, is observed subordinate to extracerebral nocardiosis. Computerized tomography scan and conventional magnetic resonance (MR) scan show lesions with a necrotic core and multilobed thick walls enhancing after injection of gadolinium or iodine. Abscesses are mainly located in the brain stem, basal ganglia and cerebral cortex of the frontal, parietal and occipital lobes; cerebellar and spinal locations are uncommon. MR diffusion-weighted imaging with calculation of apparent diffusion coefficient and proton MR spectroscopy can provide additional data for accurate differential diagnosis between abscess and other necrotic lesions, such as tumor and cyst formations. Bacteriological identification has progressed with advances in molecular microbiology: 16S rRNA sequencing, allowing a more rapid routine identification of Nocardia strains from clinical samples. Clinical management of patients with a Nocardia brain abscess relies upon early use of intravenous antibiotics adapted to the strains identified and their susceptibility. Most Nocardia strains display susceptibility to cotrimoxazol, amikacin and linezolid, but develop beta-lactamase activity. CONCLUSIONS: Early pus samples, obtained by biopsy or surgical resection, are needed to establish a certain bacteriological diagnosis and initiate appropriate intravenous antibiotics.

Hydraulic and biochemical analyses on full-scale sludge consolidation reed beds in Tuscany (Italy).

The management of sewage sludge has recently become one of the most significant challenges in wastewater management. Reed bed systems appear to be an efficient and economical solution for sludge management in small wastewater treatment plants. Four years ago, one of the holding companies for water and wastewater in central Italy adopted this technology in 6 wastewater treatment plants. Hydraulic and biochemical analyses were performed on the most representative site to asses the behaviour of reed beds with regard to dewatering, mineralization and humification of disposed sludge. Moreover, daily water content analysis were performed in the interval between subsequent sludge loadings. Results indicated a decrease of sludge volume by about 93% on a yearly basis. Biochemical analysis highlighted that mineralization processes decrease over time due to a rapid decrease of microbial activity and labile substrates, such as DHase enzyme and water-soluble carbon and ammonium, respectively. Moreover, a significant interrelationship between the parameters linked with mineralization was found: after two years of operation, the process of mineralization of organic matter is still predominant in the humification of organic matter. Daily water content data were used to define a semi empirical equation describing the dynamics of the dewatering process. Overall, the use of sludge reed beds resulted feasible, ecologically sustainable and cost-effective.

[Dilatation of Virchow-Robin perivascular spaces (types III cerebral lacunae): radio-clinical correlations]. / Dilatation des espaces périvasculaires de Virchow-Robin (Lacunes de type III): corrélations radio-cliniques.

BACKGROUND AND PURPOSE: Virchow-Robin spaces are pia-lined extensions of the subarachnoid space surrounding the path of brain vessels. When enlarged, such dilated perivascular spaces are often seen as foci of cerebrospinal fluid signal on MRI or CT scan. These foci are found in patients with miscellaneous clinical status. It is necessary to determine the radiological significance and clinical associations, if any, in such patients in order to give them the appropriate treatment. METHODS: We describe the clinical and radiological findings of five patients and review the literature on perivascular Virchow-Robin spaces. RESULTS: The mechanisms of dilated Virchow-Robin spaces are still not well understood. Such dilated perivascular spaces are found in two locations: typically in the high-convexity white matter of healthy elderly subjects, or surrounding the lenticulostriate vessels as they enter the basal ganglia. On MR images, they may be confused with lacunar infarcts. Most of the patients present with no symptoms: small dilatations located in the high convexity actually represent an anatomic variant, also called "état criblé". Sometimes, giant dilatations, or Poirier's type IIIb "expanding lacunae", found in the basal ganglia and midbrain may result in symptomatic hydrocephalus needing appropriate treatment. For other miscellaneous symptoms as headache, generalized epilepsy, dysmorphy, macrocephaly, there is no reliable correlation with enlarged perivascular spaces seen on MR images. CONCLUSIONS: The real symptomatic dilated perivascular spaces need appropriate and quick treatment. Most of the other patients present with no symptoms and will remain asymptomatic.

[Fractionated stereotactic radiotherapy for optic nerve sheath meningioma: eight cases]. / Radiothérapie stéréotaxique fractionnée des méningiomes de la gaine du nerf optique: à propos de huit cas.

UNLABELLED: Optic nerve sheath meningioma (ONSM) accounts for one-third of primary optic nerve tumors, and 2% of all meningiomas. ONSM must be distinguished from other meningiomas, in particular from cavernous meningiomas because of the different prognosis and treatment. The most frequent clinical sign is a progressive or sudden unilateral visual loss. Treatment of ONSM is still subject to discussion. This report covers a series of eight ONSM patients treated with fractionated stereotactic radiotherapy. MATERIAL AND METHODS: Between 2000 and 2006, we managed eight patients with ONSM. The average patient age was 47 years. There were five women and three men. The most frequent clinical signs were visual loss (100%), proptosis (35%), diplopia (25%). One patient was initially treated with surgery. All patient have been treated by fractionated stereotactic radiotherapy. 45 Gy in 25 fractions were delivered on the meningioma area at a rate of 5 fractions of 1.8 Gy per week. We used a Brainlab framework associated with a thermo-formed mask. A computed tomography then magnetic resonance imaging was obtained for each patient. The data was merged and planning took place on a Brainlab dosimetric console. The treatment was performed with a head-only Varion linear accelerator, with a Brainlab multi-blade collimator. RESULTS: The average follow-up was 27 months. Each patient had a complete radiological and ophthalmologic exam every 3 months during the first year, then every 6 months thereafter. Tumor control rate was 100%. Vision was re-established in five patients and three patients had improvement, including one patient during treatment. 100% of proptosis and diplopias regressed. No side effect was reported. CONCLUSION: This is still a preliminary study, but the results suggest that fractionated stereotactic radiotherapy may emerge as a primary treatment for ONSM, delaying surgery, which has proven functionally disappointing.

Genetic strategies for brain tumor therapy.

Gene therapy is a potentially useful approach in the treatment of human brain tumors, which are notoriously refractory to conventional approaches. Most human clinical trials to date have been unsuccessful in terms of improving patient outcome. Recent improvements in viral vectors, the development of stem cell technology, and increased understanding of the mechanism of action of therapeutic transgenes provide hope that the next generation of gene therapeutics may show increased efficacy in treatment of this devastating disease.

Multicolumn spinal cord stimulation for significant low back pain in failed back surgery syndrome: design of a national, multicentre, randomized, controlled health economics trial (ESTIMET Study).

BACKGROUND: Many studies have demonstrated the efficacy of spinal cord stimulation (SCS) for chronic neuropathic radicular pain over recent decades, but despite global favourable outcomes in failed back surgery syndrome (FBSS) with leg pain, the back pain component remains poorly controlled by neurostimulation. Technological and scientific progress has led to the development of new SCS leads, comprising a multicolumn design and a greater number of contacts. The efficacy of multicolumn SCS lead configurations for the treatment of the back pain component of FBSS has recently been suggested by pilot studies. However, a randomized controlled trial must be conducted to confirm the efficacy of new generation multicolumn SCS. Évaluation médico-économique de la STImulation MEdullaire mulTi-colonnes (ESTIMET) is a multicentre, randomized study designed to compare the clinical efficacy and health economics aspects of mono- vs. multicolumn SCS lead programming in FBSS patients with radicular pain and significant back pain. MATERIALS AND METHODS: FBSS patients with a radicular pain VAS score≥50mm, associated with a significant back pain component were recruited in 14 centres in France and implanted with multicolumn SCS. Before the lead implantation procedure, they were 1:1 randomized to monocolumn SCS (group 1) or multicolumn SCS (group 2). Programming was performed using only one column for group 1 and full use of the 3 columns for group 2. Outcome assessment was performed at baseline (pre-implantation), and 1, 3, 6 and 12months post-implantation. The primary outcome measure was a reduction of the severity of low back pain (bVAS reduction≥50%) at the 6-month visit. Additional outcome measures were changes in global pain, leg pain, paraesthesia coverage mapping, functional capacities, quality of life, neuropsychological aspects, patient satisfaction and healthcare resource consumption. TRIAL STATUS: Trial recruitment started in May 2012. As of September 2013, all 14 study centres have been initiated and 112/115 patients have been enrolled. Preliminary results are expected to be published in 2015. TRIAL REGISTRATION: Clinical trial registration information-URL: www.clinicaltrials.gov. Unique identifier NCT01628237.

Differentiated cerebrovascular effects of physostigmine and tacrine in cortical areas deafferented from the nucleus basalis magnocellularis suggest involvement of basalocortical projections to microvessels.

Cholinesterase inhibitors used to treat Alzheimer's disease according to the principle of cholinergic replacement therapy have proved to be less beneficial than expected. The present study was designed to investigate the cerebrovascular response to physostigmine and tacrine in the experimental model of lesioning of the nucleus basalis magnocellularis (NBM), a model involving a cholinergic deficit. Regional cerebral blood flow was measured by the [14C]iodoantipyrine tissue sampling technique in conscious rats infused with i.v. physostigmine (0.2 mg/kg/h), tacrine (8 mg/kg/h), or saline, 3-5 weeks after unilateral lesion of the NBM with ibotenic acid. Physostigmine and tacrine dose-dependently increased blood flow in most cortical and subcortical regions compared to the control group. However, physostigmine caused smaller blood flow increases in several areas, mostly cortical, of the lesioned compared to the intact hemisphere. The converse was observed with tacrine. A facilitated circulatory response appeared in cortical areas deafferented from the NBM, especially in the frontal cortex. These results provide evidence for distinct NBM-dependent components of the cortical cerebrovascular effects of physostigmine and tacrine. They suggest the involvement of different cellular postsynaptic targets of the NBM. The physostigmine-type effects could involve direct projects onto an inhibitory cortical interneuron supersensitized by deafferentation. This arrangement may explain why physostigmine and perhaps other cholinergic agonists are unable to specifically compensate for a deficit in NBM functioning. The tacrine-type effects presumably involve projections to the microvasculature, including perivascular astrocytes. The neurovascular junction would be sensitized by deafferentation from the NBM. Our data suggest that the regulatory mechanisms of blood flow originating in the NBM might constitute a target of neurodegenerative processes of Alzheimer's disease.

Tacrine overcompensates for the decreased blood flow induced by basal forebrain lesion in the rat.

The effects of tacrine on the cerebral blood flow (CBF) were investigated according to an experimental model of the cholinergic hypothesis in rats with unilateral lesion of the substantia innominata (SI). CBF was measured 1-2 weeks following SI lesion with ibotenic acid, using the tissue sampling [14C]iodoantipyrine technique in three groups of lesioned rats infused i.v. with tacrine at 3 or 8 mg kg-1 h-1 or with saline. SI lesioning resulted in moderate, significant blood flow decreases in the parietal, frontal and occipital cortical areas. In the intact hemi-brain, tacrine at a dose of 3 mg kg-1 h-1 had no significant effect, but at 8 mg kg-1 h-1 tacrine increased the blood flow in most of the cortical and subcortical regions investigated. The increases ranged from 21% (hypothalamus) to 101% (parietal cortex) compared with controls. Tacrine had greater effects in the lesioned hemisphere, even at the dose of 3 mg kg-1 h-1. The flow increases in the frontal or parietal cortex of the lesioned hemisphere were 1.5-3.6 times greater than in the intact hemisphere. Thus, in contrast to what was expected, tacrine overcompensates for the cerebrovascular effects of SI lesions.

[Fractionated stereotactic radiotherapy: results in hypophyseal adenomas, acoustic neurinomas, and meningiomas of the cavernous sinus]. / Radiothérapie stéréotaxique fractionnée: résultats dans les adénomes hypophysaires, les neurinomes de l'acoustique et les méningiomes du sinus caverneux.

PURPOSE: In order to optimize cerebral benign tumor irradiation, fractionated stereotactic radiotherapy allows a focused-volume irradiation (2.1 cm3, 16 mm diameter) under standard fractionation conditions. Results of a retrospective and multicentric analysis are presented. PATIENTS AND METHODS: Fractionated stereotactic radiotherapy uses the ballistic principles of the radiosurgery: stereotactic localization, multi-beam irradiation, secondary collimation, three-dimensional dosimetry. Standard fractionation is possible with a re-locatable non-invasive stereotactic device. The technique has been used for treating pituitary adenomas (86 patients), acoustic neuromas (32 patients) and cavernous meningiomas (26 patients). RESULTS: 1) pituitary adenomas: cumulative tumoral objective-response rates (42 patients) were respectively 42%, 69% and 88% at 24, 48 and 60 months. The cumulative endocrinologic objective-response rates (32 patients) were respectively 53%, 75% and 85% at 24, 48 and 60 months. The cumulative risk of radio-induced hormonal deficiency varied from 18% (growth hormone [GH]) to 42% for TSH (thyroid stimulating hormone) at 48 months. No other complication was observed; 2) acoustic neuromas: 33 tumors, < 25 mm in diameter, were treated in 32 patients. Tumor control was observed in 29/33 tumors: 14 were stable, 15 decreased and three progressed. Useful hearing was maintained in 9/10 patients. Only three patients (9%) presented persistent complications; 3) cavernous meningioma: 17/19 clinical responses were noted, 20 tumoral stabilisations, one partial response and one progression (22 magnetic resonance imaging [MRI] evaluable patients). One unilateral radio-induced blindness was observed. CONCLUSION: For these benign tumors, the focused target volume obtained by the fractionated stereotactic radiotherapy seems to be better adapted to the treatment of limited benign tumors than standard radiotherapy. The use of standard fractionation reduces the risk of severe normal tissue damage, sometimes observed for radiosurgery and inherent in the use of single fraction.

[Should Tolosa-Hunt syndrome still be an exclusion diagnosis?]. / Le syndrome de Tolosa-Hunt doit-il encore être un diagnostic d'élimination?

Since Hunt et al's description (1961) Tolosa-Hunt syndrome has been a matter of controversies about its nosological identity and differential diagnosis. We report 7 cases diagnosed between 1979 and 1990. Four of them had a low-resolution CT and the diagnosis was made after a long follow-up, according to classical criteria of exclusion. The last 3 cases had a modern high-resolution CT or a MRI (2 cases) and the diagnosis was established in a few days. MRI has considerably simplified the differential diagnosis but it has not completely resolved it. Alterations of shape and signal of the cavernous sinus are similar to those of lymphoma, sarcoidosis and meningioma. When MRI is normal diabetic ophthalmoplegia, migrainous ophthalmoplegia and giant-cell arteritis must also be considered. We conclude that the diagnosis of the Tolosa-Hunt syndrome can generally be made in a few days, without a cavernous sinus biopsy. There is no reason to doubt that this syndrome is a specific nosological entity.

[Cardiac myxoma with cerebral metastases]. / Myxome cardiaque avec métastases cérébrales.

A 56 year old woman developed multiple metastases in the cerebrum and cerebellum, four years after cardiac intervention on a left atrial myxoma. The absence of stroke is noteworthy. Multiple high density lesions with contrast enhancement were seen by CT scan, suggesting metastatic neoplasms. Histological examination confirmed the diagnosis of metastases of cardiac myxoma. Only four cases were recorded in the literature.

[Postoperative spinal extradural hematomas. 14 cases]. / Hématomes extra-duraux rachidiens post-opératoires. Quatorze observations.

We report 14 cases of post-operative spinal epidural hematoma and compare them with 17 cases reported in the literature. These 14 cases have been drawn from a continuous series of 7950 patients operated on at our institution by the posterior route for a non-traumatic spinal pathology. The symptom-free period after initial surgery was shorter than 5 hours in 13 cases out of 14. The clinical picture was characteristic 11 times. It started with a stabbing pain in the operated site, followed by paresthesia, radicular pain and neurologic palsy which were always bilateral even when the operation had been unilateral. The diagnosis was always established rapidly when the compression was cervical or thoracic and with some delay when the lumbar area was concerned. All patients, except one, have been reoperated without any radiological investigation. The source of bleeding was found 12 time out of 14. Full recovery was obtained in all 14 patients but delayed recovery of a few weeks occurred in 3 patients for whom reoperation was delayed. None of the potentiating factors studied in this work were found to be decisive. Post-operative spinal epidural hematoma is a rather uncommon complication of spinal surgery occurring at a rate of 1 to 2 per thousand. The diagnosis is more often obvious because its clinical picture is similar to that of spontaneous spinal epidural hematoma. Early reoperation allows a full recovery. Special attention during the first six post-operative hours for all patients after spinal surgery is essential for early detection of such a complication.

[Myelopathies caused by dorsal spinal canal spondylotic stenosis. 3 cases and a review of the literature]. / Myélopathies par sténose arthrosique du canal rachidien dorsal. 3 observations et revue de la littérature.

Thoracic spondylotic myelopathies are exceptional, only 29 observations could be found in the literature; we intend to describe three new cases here. The patients, two women and one man, 64, 69 and 72 years old, complained of weakness of the lower limbs, more marked on one side, which had been progressing slowly from several months to eight years. Examination revealed asymmetrical paraparesis with distal sensitivity deficits without thoracic sensory level. In the first case, the myelography remained virtually unchanged in front of T11, T12; in the second and third cases, there was slight extradural compression at T9 and T10 respectively. Magnetic Resonance Imaging (M.R.I.) performed in two patients was evocative of a thoracic disk herniation. A chest CT scan enabled us to establish correct diagnosis: in the three cases irregular hypertrophy of the posterior elements was evident at T11 and T12, T9 and T10, T10 and T11 respectively, with osteophytes originating in the articular process and deeply embedded in the spinal canal. Decompressive laminectomy associated with medial facetectomy resulted in the gradual improvement of walking in all three patients. Myelography and MRI are both useful in demonstrating the level compression, usually situated in the low thoracic spine, however only the CT allows differential diagnosis with other etiologies, especially anterior compression such as disk herniation.

[Cervical spondylotic myelopathies. Apropos of 121 cases. Prognostic value of sensitive symptoms]. / Myelopathies cervicarthrosiques à propos de 121 observations. Intérêt pronostique des troubles sensitifs.

121 patients have been treated for cervical spondylotic myelopathy between 1972 and 1985; 88 patients have been operated on, most of them (84) by laminectomy and 4 cases by anterior approach; 33 patients have been treated conservatively in absence of evolution. We have used a clinical classification based on the different sensitive symptoms, the best predictive factor in our opinion; the typical form (2/3 of all cases) associates numbness and paresthesias of extremities of both hands, difficulties for manipulation, astereognosia, with a moderate pyramidal deficit of the lower limbs; this typical form obtains the best post-operative score with 75% of good results; the more the clinical sensitive form is far from the typical one, the poorest may be the evolution. Our results are similar with large series of literature, using either the posterior or the anterior approach; we have noted the frequency (1/4 of cases) of very late worsening, several years after initial good result, without residual compressive factor; it is supposed that organised intra-medullary lesions, may be of venous origin, continue to evolve for their own. 33 non operated patients have been treated conservatively, because of spontaneous stabilization of their disease, suggesting to try immobilization by cervical collar during few weeks before surgery.

[Cerebral abscess and Osler-Rendu disease. Apropos of 4 cases]. / Abcès cérébraux et maladie de Rendu Osler. A propos de 4 cas.

The authors report 4 cases of cerebral abscesses (C.A.) complicating Rendu Osler disease (hereditary haemorrhagic telangiectasia: H.H.T.). These cases and 43 others comparable found in literature enable to assess C.A. complicates H.H.T. by the way of pulmonary arteriovenous fistulas (P.A.V.F.). C.A. appears during known H.H.T. in only a quarter of cases; in all other cases C.A. reveals the disease. When the etiological search for metastatic C.A. fails to find any classical cause: O.R.L., stomatologic, cardiac, it seems important to suspect H.H.T., and research P.A.V.F. by chest X ray and pulmonary angiography. Preventive treatment consists in excluding pulmonary fistulas without waiting neurological complications of known H.H.T.

[Synovial cysts and synovialomas of the lumbar spine. Histo-pathologic and neuro-surgical aspects apropos of 8 cases]. / Kystes synoviaux et synovialomes du rachis lombaire. Aspects histo-pathologiques et neuro-chirurgicaux à propos de 8 observations.

Based on 8 personal cases and a 81-cases review of literature, it's authors' opinion that cystic or solid masses issued form posterior lumbar articular process and called according to the cases synovial cyst, ganglion cyst, benign synovialoma, pigmented villonodular synovitis, are a single variety of benign degeneration of soft articular tissues. The cystic or solid feature of these masses depends upon the extent of their histiocytic granulomatous proliferation. They may be asymptomatic, accompany chronic lumbar pain or cause sciatica, seldom cauda equina syndrome. In case of sciatica, clinical picture rather consists of a narrow lateral recess than a discal protrusion. CT scan is the best investigation to get a right preoperative diagnosis. Postoperative prognosis is excellent and no anatomical recurrence has been reported.

[Spondylodiscitis after surgery of lumbar disk hernia. Apropos of 12 cases in 1796 operations]. / Spondylodiscite après chirurgie de la hernie discale lombaire. A propos de 12 cas sur 1,796 opérés.

Discitis is a rare complication of disc operation. The incidence rate varies from 0.2 to 0.8% according to the series. During a 6 year period (1980-1986) 1,796 patients were operated for lumbar disc protrusion at our institution and twelve of them (0.66%) developed a post operative discitis. Bacteriologic verification due to the infection was ascertained in ten cases. Direct contamination during surgical time is likely far more frequent than hematogenous contamination because the liable germ was staphylococcus in 9 cases. Ascertaining the diagnosis is base upon clinical picture and some selected investigations. It may be earlier than it has been said before. Discitis may be suspected within a week after operation in two cases out of three. The most prominent clinical feature is back pain with muscle spasm but sometimes diagnosis may be misled to a psychiatric condition or a visceral disorder. Among conclusive investigations we range in the first place the needle aspiration of the disc which permitted to isolate a germ nine times out of eleven. Next the bone scan with H.M.D.P. Te 99 (8 Mbq/kg) which revealed a significant uptake pattern in eight cases out of eight. Finally the blood culture which grew five times out of ten. Risks of discitis, i.e septicemia, polysegmental infection or death justify in our opinion an appropriate antibiotherapy during at least 8 weeks. Moreover, in our experience, it is the best antalgic treatment that we can offer and back pain decreases as soon as the second day with antibiotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)