Giuseppe Barbagallo

Analysis of complications in patients treated with the X-Stop Interspinous Process Decompression System: proposal for a novel anatomic scoring system for patient selection and review of the literature.

OBJECTIVEThe X-Stop Interspinous Process Decompression System (St. Francis Medical Technologies, Concord, CA) is an interspinous device used with increasing frequency in the treatment of degenerative lumbar spine conditions. To date, limited data are available on complications observed in association with X-Stop procedures, and even less information exists on their underlying causes. The aim of this study was to analyze a series of complications occurring at a single institution and their potential causes and propose an anatomic scoring system that may help to classify patients and prevent complications. METHODSSixty-nine patients were treated with the X-Stop. Forty-six single-level and 23 double-level operations (92 devices) were performed according to recommended indications. The mean follow-up duration was 23 months. RESULTSEight complications were recorded: 4 device dislocations and 4 spinous process (SP) fractures, including 2 spontaneous fractures of the L4 SP in patients treated at L3–L4 and L4–L5. The following anatomic variants were demonstrated: markedly decreased interspinous distance (kissing spine–like), with concomitant facet joint hypertrophy, a posterior V-shaped interspinous area, limited accessibility of the space between the base and the tip of the SP because of facet joint hypertrophy and variations in the shape of the inferior surface of the cranial SP. CONCLUSIONThis is the first study focusing on interspinous distractor complications and the anatomic features of the SP and interspinous areas of the patients, which could potentially be the underlying causes for those complications. The X-Stop can be an effective treatment option, but it is not a panacea for all patients with degenerative lumbar spine conditions. Not only do the clinical indications deserve attention, but also, and most importantly, the patients anatomic characteristics.

‘Recurrent’ glioblastoma multiforme, when should we reoperate?

The surgical management of recurrent glioblastoma multiforme is controversial. Recent publications suggest that re-operation provides 3–5 months median survival, without significant increases in morbidity or martality. Age (≤50 years, although older patients may also benefit) and performance status (Karnofsky performance score ≥60–70) are the most important factors. Reresection not only improves symptoms and maintains quality of life, it can delay symptom progression, reduce corticosteroid doses, and also improve response to (and allow intra-operative) chemotherapy and/or radiotherapy. Surgical treatment of recurrent glioblastoma multiforme in selected patients should always be considered.

A global perspective on the outcomes of surgical decompression in patients with cervical spondylotic myelopathy: results from the prospective multicenter AOSpine international study on 479 patients.

Study Design. Prospective, multicenter international cohort. Objective. To evaluate outcomes of surgical decompression for cervical spondylotic myelopathy (CSM) at a global level. Summary of Background Data. CSM is a degenerative spine disease and the most common cause of spinal cord dysfunction worldwide. Surgery is increasingly recommended as the preferred treatment strategy for CSM to improve neurological and functional status and quality of life. The outcomes of surgical intervention for CSM have never been evaluated at an international level. Methods. Between October 2007 and January 2011, 479 symptomatic patients with image evidence of CSM were enrolled in the prospective, multicenter AOSpine CSM-International study from 16 global sites. Preoperative and postoperative clinical status, functional impairment, and quality of life were evaluated using the modified Japanese Orthopaedic Assessment Scale, Nurick Scale, Neck Disability Index, and Short-Form-36v2. Preoperative and 12- and 24-month postoperative outcomes were compared using mixed-model analysis of covariance for repeated measurements. Results. The study cohort consisted of 310 males and 169 females, with a mean age of 56.37 ± 11.91 years. There were significant differences in age, etiology, and surgical approaches between the regions. At 24 months postoperatively, the mean modified Japanese Orthopaedic Assessment Scale score improved from 12.50 (95% confidence interval [CI], 12.24–12.76) to 14.90 (95% CI, 14.64–15.16); the Neck Disability Index improved from 36.38 (95% CI, 34.33–38.43) to 23.20 (95% CI, 21.24–25.15); and the SF36v2 Physical Component Score and Mental Composite Score improved from 34.28 (95% CI, 33.46–35.10) to 40.76 (95% CI, 39.71–41.81) and 39.45 (95% CI, 38.25–40.64) to 46.24 (95% CI, 44.94–47.55), respectively. The rate of neurological complications was 3.13%. Conclusion. Surgical decompression for CSM is safe and results in improved functional status and quality of life in patients around the world, irrespective of differences in medical systems and sociocultural determinants of health. Level of Evidence: 3

Positioning on surgical table

Positioning on the surgical table is one of the most important steps in any spinal surgical procedure. The “prone position” has traditionally been and remains the most common position used to access the dorsolumbar-sacral spine. Over the years, several authors have focused their attention on the anatomy and pathophysiology of both the vascular system and ventilation in order to reduce the amount of venous bleeding, as well as to prevent other complications and facilitate safe posterior approaches. The present paper reviews the pertinent literature with the aim of highlighting the advantages and disadvantages of various frames and positions currently used in posterior spinal surgery.

Upregulation of neuronal nitric oxide synthase in in vitro stellate astrocytes and in vivo reactive astrocytes after electrically induced status epilepticus.

Neuronal nitric oxide synthase (nNOS) is a constitutively expressed and calcium-dependent enzyme. Despite predominantly expressed in neurons, nNOS has been also found in astrocytes, although at lower expression levels. We have studied the regulation of nNOS expression in cultured rat astrocytes from cortex and spinal cord by Western blotting and immunocytochemistry. nNOS was not detectable in cultured astrocytes grown in serum-containing medium (SCM), but was highly expressed after serum deprivation. Accordingly, calcium-dependent NOS activity and both intracellular nitrite levels and nitrotyrosine immunoreactivity after glutamate stimulation were higher in serum-deprived astrocytes than in cells grown in SCM. Serum deprivation induced a modification of astrocytes morphology, from flat to stellate. nNOS upregulation was also observed in reactive astrocytes of rat hippocampi after electrically induced status epilepticus, as demonstrated by double-labeling experiments. Thus, nNOS upregulation occurs in both in vitro stellate and in vivo reactive astrocytes, suggesting a possible involvement of glial nNOS in neurological diseases characterized by reactive gliosis.

Dysregulated miR-671-5p / CDR1-AS / CDR1 / VSNL1 axis is involved in glioblastoma multiforme

MiR-671-5p is encoded by a gene localized at 7q36.1, a region amplified in human glioblastoma multiforme (GBM), the most malignant brain cancer. To investigate whether expression of miR-671-5p were altered in GBM, we analyzed biopsies from a cohort of forty-five GBM patients and from five GBM cell lines. Our data show significant overexpression of miR-671-5p in both biopsies and cell lines. By exploiting specific miRNA mimics and inhibitors, we demonstrated that miR-671-5p overexpression significantly increases migration and to a less extent proliferation rates of GBM cells. Through a combined in silico and in vitro approach, we identified CDR1-AS, CDR1, VSNL1 as downstream miR-671-5p targets in GBM. Expression of these genes significantly decreased both in GBM biopsies and cell lines and negatively correlated with that of miR-671-5p. Based on our data, we propose that the axis miR-671-5p / CDR1-AS / CDR1 / VSNL1 is functionally altered in GBM cells and is involved in the modification of their biopathological profile.

Lumbar Lateral Interbody Fusion (LLIF): Comparative Effectiveness and Safety versus PLIF/TLIF and Predictive Factors Affecting LLIF Outcome

Study Design Systematic review. Study Rationale The surgical treatment of adult degenerative lumbar conditions remains controversial. Conventional techniques include posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion (TLIF). A new direct approach known as lumbar lateral interbody fusion (LLIF), or extreme lateral interbody fusion (XLIF®) or direct lateral interbody fusion (DLIF), has been introduced. Objectives The objective of this article is to determine the comparative effectiveness and safety of LLIF, at one or more levels with or without instrumentation, versus PLIF or TLIF surgery in adults with lumbar degenerative conditions, and to determine which preoperative factors affect patient outcomes following LLIF surgery. Materials and Methods A systematic review of the literature was performed using PubMed and bibliographies of key articles. Articles were reviewed by two independent reviewers based on predetermined inclusion and exclusion criteria. Each article was evaluated using a predefined quality rating scheme. Results The search yielded 258 citations and the following met our inclusion criteria: three retrospective cohort studies (all using historical cohorts) (class of evidence [CoE] III) examining the comparative effectiveness and safety of LLIF/XLIF®/DLIF versus PLIF or TLIF surgery, and one prospective cohort study (CoE II) and two retrospective cohort studies (CoE III) assessing factors affecting patient outcome following LLIF. Patients in the LLIF group experienced less estimated blood loss and a lower mortality risk compared with the PLIF group. The number of levels treated and the preoperative diagnosis were significant predictors of perioperative or early complications in two studies. Conclusion There is insufficient evidence of the comparative effectiveness of LLIF versus PLIF/TLIF surgery. There is low-quality evidence suggesting that LLIF surgery results in fewer complications or reoperations than PLIF/TLIF surgery. And there is insufficient evidence that any preoperative factors exist that predict patient outcome after LLIF surgery.

The "sandwich phenomenon": a rare complication in adjacent, double-level X-stop surgery: report of three cases and review of the literature.

Study Design. Case reports. Objective. To report the atraumatic fracture of the intervening (L4) spinous process (SP) in patients treated with X-Stop at 2 adjacent levels and discuss the potential underlying causes. Summary of Background Data. Limited evidence on complications in double-level X-Stop surgery is available. Methods. Three men, 47, 63, and 75 years old, respectively, underwent surgery with insertion of X-Stop at L3–L4 and L4–L5 because of low back pain and neurogenic claudication due to degenerative lumbar spine conditions. Two 10 mm devices were implanted in the first patient and two 16 mm distractors in the second man. One 10 mm X-Stop at L3–L4 and one 12 mm at L4–L5, respectively, were implanted in the third patient. No intraoperative complications occurred and the postoperative course was uneventful, with symptoms relief. Results. The first 2 patients presented because of recurrent symptoms 4 and 6 months after surgery, respectively. Imaging revealed “spontaneous” fracture of the L4 SP in both of them. Revision surgery was required, with removal of the interspinous devices, decompression and fixation. In the third patient the L4 SP fracture was detected when the patient presented because of recurrent back pain 18 months after the index surgery, but revision surgery was not consented. Conclusion. To our knowledge this is the first report describing the “sandwich phenomenon,” i.e., the atraumatic fracture of the intervening SP in patients with adjacent, double-level X-Stop. Possible underlying theories and anatomic peculiarities which may predispose to this rare event are discussed.

Giant cell ependymoma of the cervical spinal cord: case report and review of the literature

Ependymomas account for 2–6% of all central nervous system neoplasms. They develop from the ependymal cells that line the ventricular cavities of the brain and the central canal of the spinal cord, as well as from ependymal clusters in the filum terminale. Giant cell ependymoma (GCE) is a rare subtype, with few cases reported, mostly in the brain. We describe the case of a cervical spinal cord ependymoma with pleomorphic giant cells and focal calcifications occurring in a 25-year-old woman. Magnetic resonance imaging revealed a large multicystic and partially enhancing intramedullary tumour extending from C2 to C5. Intraoperative analysis of frozen section tissue fragments suggested a malignant tumour; however, an obvious cleavage plane was present around most of the mass, and a macroscopically complete tumour removal could be achieved. Subsequently, paraffin sections and immunohistochemical investigations revealed unequivocal evidence of a GCE with focal calcifications. This case, the second giant-cell ependymoma to be described in the spinal cord and the first with focal calcifications, highlights the features of GCE and the discrepancy between the worrisome histological appearance, the surgical findings and the clinical relatively good prognosis.

Review of current microsurgical management of insular gliomas

The insular lobe is a functionally complex structure, harbouring peculiar anatomical and vascular features and specific neuronal connectivity with surrounding cerebral structures. It is situated in the depth of the Sylvian fissure and can be affected by either low-grade or high-grade gliomas. Because of its complexity, surgery of insular tumours has been traditionally regarded as hazardous. Nonetheless, currently improved diagnostic, neurophysiological and surgical tools allow the neurosurgeon to perform surgery of insular gliomas in a safer way, thus bringing forward the pioneering work performed by neurosurgeons in the past two decades.The aim of this paper is to provide the reader with an updated review of the anatomy, the clinical picture, diagnosis and surgical management of insular gliomas.