bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extrathecal intraradicular nerve sheath tumor
Authors: Celli Paolo , Trillò Giuseppe , Ferrante Luigi 
Published: May 2009

Object. The purpose of this study was to analyze the clinical profile of patients harboring extrathecal and intraradicular nerve sheath tumors (NSTs), located inside the sleeve of an extrathecal nerve root and very often within the proximal portion of the spinal nerve, and to evaluate the incidence of long-term dysfunction of the tumor-affected roots if resected. These tumors have not received particular attention in the literature.
Methods. A single-institution series of 16 patients who had undergone surgery for intraradicular NSTs during a 50-year period was selected retrospectively. Data pertaining to clinical features, tumor characteristics, and results of surgery were analyzed.
Conclusions. Extrathecal and intraradicular neurofibromas or schwannomas more frequently affect the lumbar and S-1 nerve roots, often producing root pain only. Selective en bloc enucleation sparing at least part of the motor rootlets is possible for small schwannomas of the extrathecal—preganglion segment of the radix, whereas total resection of the affected root is generally required for radical removal of neurofibromas and large schwannomas. In the authors' experience, neither deafferentation pain nor severe radicular weakness occurs after division of the nerve root harboring the tumor.
Functional outcome after surgical treatment of spontaneous and nonspontaneous spinal subdural hematomas
Authors: Thiex Ruth , Thron Armin , Gilsbach Joachim M. , Rohde Veit 
Published: May 2009

Object. Because of the rarity of spinal subdural hematomas (SDHs), the literature offers scarce estimates of the outcome and predictive factors in patients suffering from these lesions. In addition, single-institution surgical series are still lacking. Therefore, the authors retrospectively evaluated the early and long-term functional outcomes measured in eight patients with spontaneous and nonspontaneous spinal SDHs in whom the clot had been evacuated.
Methods. The patients' charts were evaluated for origin of the lesion, risk factors, and neurological deficits at symptom onset and at 28 days after extirpation of the spinal SDH. Long-term clinical outcome (Barthel Index [BI]) was evaluated by administering a telephone questionnaire to the patient or a relative.
Only one patient with a spontaneous spinal SDH was identified. Four patients were undergoing anticoagulant therapy, and three patients had undergone a previous anesthetic/diagnostic spinal procedure. Twenty-eight days postoperatively, neurological deficits improved in six of eight patients; however, in two of the six patients, the improvement did not allow the patients to become independent again. In two patients, surgery did not affect the complete sensorimotor deficits. In the long-term survivors (median 45 months) a median BI of 55 was achieved. The latency between symptom onset and surgery did not correlate with functional outcome in this series. The preoperative neurological condition and location of the hematoma correlated positively with early and long-term functional outcome.
Conclusions. To the best of their knowledge, the present study is the largest single-institutional study of patients with surgically treated spinal SDHs. Despite some postoperative improvement of sensorimotor deficits in most patients, the prognosis is poor because 50% of the patients remain dependent. Their outcome was determined by the preoperative sensorimotor function and spinal level of the spinal SDH.
Multicenter study investigating the postoperative progression of ossification of the posterior longitudinal ligament in the cervical spine: a new computer-assisted measurement
Authors: Chiba Kazuhiro , Yamamoto Itsuo , Hirabayashi Hisashi , Iwasaki Motoki , Goto Hiroshi , Yonenobu Kazuo , Toyama Yoshiaki 
Published: May 2009

Object. Ossification of the posterior longitudinal ligament (OPLL) often progresses after surgery, and this may cause late-onset neurological deterioration. There have been few studies, however, to clarify any correlation between progression and clinical outcome, partly because of the lack of studies involving reliable and reproducible methods by which detection of progression is made possible. The authors conducted a multicenter study to investigate the occurrence of postoperative progression and to elucidate the possible risk factors in a large-scale patient population, and a novel computer-assisted measurement method was used to provide the basis for future clinical studies.
Methods. The authors analyzed lateral plain radiographs obtained immediately and at 1 and 2 years after surgery in 131 patients who underwent posterior decompression at 13 institutions. The x-ray films were transformed via scanner into digital images; the length and thickness of ossifications were measured using a new computer-assisted measurement system, and the incidence of progression was determined. Odds ratios for progression according to age group and types of OPLL were determined and compared to elucidate significant risk factors of progression.
Conclusions. This is the first multicenter study to investigate the incidence of OPLL progression after posterior decompression by using a standardized measurement method. The rate of postoperative progression at 2 years was 56.5%, which was comparable with results reported in other studies. Progression occurred more frequently in younger-age rather than in older-age patient populations at both 1 and 2 years postoperatively. Mixed-type and continuous-type OPLL progressed more frequently than the segmental-type lesion at 2 years. The results of the present study could serve as basis for future studies to assess the efficacy of drug therapy to prevent OPLL progression.
En bloc laminoplasty without dissection of paraspinal muscles
Authors: Hosono Noboru , Sakaura Hironobu , Mukai Yoshihiro , Ishii Takahiro , Yoshikawa Hideki 
Published: May 2009

Object. Although conducting cervical laminoplasty in patients with multisegmental cord compression provides good neurological results, it is not without shortcomings, including C-5 palsy, axial neck pain, and undesirable radiologically detectable changes. Postoperative kyphosis and segmental instability can cause neurological problems and are believed mainly to result from neck muscle disruption. The authors developed a new laminoplasty technique, with the aim of preserving optimal muscle function.
Methods. The present technique is a modification of unilateral open-door laminoplasty. By using an ultrasonic osteotome in small gaps of muscle bellies, a gutter is made without disrupting muscles, spinous processes, or their connections on the hinged side. Ceramic spacers are then positioned between elevated laminae and lateral masses at C-3, C-5, and C-7 on the opened side, which is exposed in a conventional manner.
This new procedure was used to treat 37 consecutive patients with compression myelopathy. Postoperative computerized tomography (CT) scanning revealed a significant difference in a cross-sectional area of muscles between the hinged and opened side. The mean follow-up period was 40.2 months (range 24–54 months). Changes in alignment were observed in only one patient, and vertebral slippage developed in two. Performed at regular intervals, CT scanning demonstrated that the elevated laminae remained in situ throughout the study period.
Conclusions. In using the present unilateral open-door laminoplasty technique, deep extensor muscles are left intact along with their junctions to spinous processes on the hinged side. Radiologically documented changes were minimal because the preserved muscles functioned normally immediately after the operation.
Murine spinal fusion induced by engineered mesenchymal stem cells that conditionally express bone morphogenetic protein—2
Authors: Hasharoni Amir , Zilberman Yoram , Turgeman Gadi , Helm Gregory A. , Liebergall Meir , Gazit Dan 
Published: May 2009

Object.The authors hypothesized that spinal fusion can be achieved and monitored by using cell-mediated gene therapy. Mesenchymal stem cells (MSCs) genetically engineered to express recombinant human bone morphogenetic protein—2 (rhBMP-2) conditionally, were implanted into the paraspinal muscles of mice to establish spinal fusion. The goal was to demonstrate an MSC-based gene therapy platform in which controlled gene expression is used to obtain spinal fusion in a murine model.Methods.Mesenchymal stem cells expressing therhBMP-2gene were injected into the paravertebral muscle in mice. Bone formation in the paraspinal region was longitudinally followed by performing micro—computerized tomography scanning, histological studies, and an analysis ofosteocalcinexpression to demonstrate the presence of engrafted engineered MSCs. The minimal period of rhBMP-2 expression by the engineered MSCs required to induce fusion was determined.The results of this study demonstrate that genetically engineered MSCs induce bone formation in areas adjacent to and touching the posterior elements of the spine. This newly formed bone fuses the spine, as demonstrated by radiological and histological studies. The authors demonstrate that injected cells induce active osteogenesis at the site of implantation for up to 4 weeks postinjection. They found that a 7-day induction of rhBMP-2 expression in genetically engineered MSCs was sufficient to form new bone tissue, although the quantity of this bone increased as longer expression periods were implemented.Conclusions.After their injection genetically engineered MSCs can efficiently form new bone in the paraspinal muscle of the mouse to obtain spinal fusion. The extent and quantity of this newly formed bone can be monitored by controlling the duration ofrhBMP-2gene expression.
Mexiletine treatment—induced inhibition of caspase-3 activation and improvement of behavioral recovery after spinal cord injury
Authors: Kaptanoglu Erkan , Caner Hakan , Solaroglu Ihsan , Kilinc Kamer 
Published: May 2009

Object. It has been demonstrated in several experimental studies that apoptosis contributes to cellular damage after spinal cord injury (SCI). During apoptosis dying cells secrete additional mediators of apoptosis such as cytokines and free radicals which have additional toxic effects and exacerbate neuronal death. The aim of this laboratory study was to investigate the effects of mexiletine on caspase-3 activation and functional recovery and compare its post-SCI effectiveness with methylprednisolone.
Methods. The rats were divided into five groups. Animals in the trauma group underwent traumatic interventions after laminectomy. Spinal cord contusion injury was produced using the weight-drop method. Animals in treatment groups received a single dose of methylprednisolone sodium succinate (Group C), single dose of mexiletine (Group D), or vehicle solution (saline; Group E) intraperitoneally immediately after injury. Hind-limb functions were assessed using the inclined plane technique and caspase-3 activity in tissue samples was measured 24 hours after SCI. Traumatic injury was found to increase tissue caspase-3 activity. In both treatment groups the drug prevented an increase in caspase-3 activity. Mexiletine treatment improved early behavioral recovery after SCI.
Conclusions. The results obtained in this study demonstrated that mexiletine treatment inhibits caspase-3 activation and preserve/restore better neuronal function compared with methylprednisolone after experimental SCI.
Late vertebral body fracture after lumbar transpedicular fixation
Authors: Missori Paolo , Ramieri Alessandro , Costanzo Giuseppe , Peschillo Simone , Paolini Sergio , Miscusi Massimo , D'Andrea Giancarlo , Delfini Roberto 
Published: May 2009

✓ Late-onset vertebral body (VB) fracture after lumbar transpedicular fixation has not been previously described in the literature. The authors present three cases in which VB fracture occurred several months after posterolateral fixation in patients with degenerative disease or traumatic injury. The authors suggest that postoperative osteopenia, modified load-sharing function, and intravertebral clefts were responsible for the fractures.
Two women and one man were evaluated at a mean follow-up interval of 3 months. Two patients suffered recurrent lumbar pain. Radiography and magnetic resonance imaging revealed fracture of some of the instrumentation-treated VBs. These two patients underwent surgical superior or inferior extension of instrumentation. The third, an asymptomatic patient, received conservative management. The two patients who underwent reoperation made complete recoveries, and there was no evidence of further bone collapse in any case.
The authors speculate that alterations in the VBs may occur following application of spinal instrumentation. In rare cases, the device can fracture and consequently lead to recurrent lumbar back pain. Recovery can be achieved by extending the instrumentation in the appropriate direction.
Minimally invasive microendoscopy-assisted transforaminal lumbar interbody fusion with instrumentation
Authors: Isaacs Robert E. , Podichetty Vinod K. , Santiago Paul , Sandhu Faheem A. , Spears John , Kelly Kevin , Rice Laurie , Fessler Richard G. 
Published: May 2009

ObjectThe authors have developed a novel technique for percutaneous fusion in which standard microendoscopic discectomy is modified. Based on data obtained in their cadaveric studies they considered that this minimally invasive interbody fusion could be safely implemented clinically. The authors describe their initial experience with a microendoscopic transforaminal lumbar interbody fusion (METLIF) technique, with regard to safety in the placement of percutaneous instrumentation, perioperative morbidity, and early postoperative results.MethodsThe METLIF procedure was performed unilaterally in 20 patients with single-level lumbar spondylolisthesis or pure mechanical back pain with endoscopic assistance, hemilaminectomy, unilateral facetectomy, and microdiscectomy. Two interbody grafts were placed via the lateral exposure of the disc space. Bilateral percutaneous pedicle screws were then inserted.Compared with patients who had undergone single-level posterior LIF at the same institutions, intraoperative blood loss, hospital length of stay (LOS), and postoperative narcotic agent use were significantly lower in the METLIF group. The mean LOS for the percutaneous fusion group was 3.4 days (5.1 days in those who underwent PLIF; p < 0.02). There have been no procedure-related complications in this series to date.ConclusionsThe METLIF technique provided an option for percutaneous interbody fusion similar to that in open surgery while minimizing destruction to adjacent tissues. This technique was safe and exhibited a trend toward decreased intraoperative blood loss, postoperative pain, total narcotic use, and the risk of transfusion.
Timing of surgical stabilization after cervical and thoracic trauma
Authors: Albert Todd J. , Kim David H. 
Published: May 2009

✓ Appropriate timing for surgical intervention following destabilizing cervical or thoracic spine trauma remains controversial. Clinical investigators have failed to provide convincing evidence that the timing of surgery significantly affects neurological outcome in most situations. Nevertheless, early surgical stabilization of the injured spine has been shown to provide significant nonneurological benefits such as more rapid patient mobilization, facilitation of treating associated injuries, reduction in rates of pulmonary and pressure sore complications, reduction in duration of intensive care unit and hospital stays, and a decrease in overall medical costs.The findings of basic science studies have improved our understanding of the molecular and cellular events surrounding initial and secondary spinal cord injury (SCI), and analysis of these findings suggests that the early postinjury period may present a unique opportunity for meaningful intervention. This possibility has been supported by results obtained in animal studies that demonstrate the potential for improving functional outcome when surgical intervention is performed within a few hours following experimental SCI. Despite the absence of significant neurological recovery in most clinical studies, the results of most recent clinical studies strongly support the overall clinical benefits of early surgical intervention, particularly in the setting of unstable thoracic spinal column injury with associated SCI. Based on the best available scientific and clinical evidence, the authors report that it is therefore recommended that surgical stabilization be performed in as timely a fashion as possible, particularly for unstable thoracic spine trauma, within the constraints of the patient's overall medical condition and availability of appropriate resources.
Long-term results after expansive open-door laminoplasty for the segmental-type of ossification of the posterior longitudinal ligament of the cervical spine: a comparison with nonsegmental-type lesions
Authors: Ogawa Yuto , Chiba Kazuhiro , Matsumoto Morio , Nakamura Masaya , Takaishi Hironari , Hirabayashi Hisashi , Hirabayashi Kiyoshi , Nishiwaki Yuji , Toyama Yoshiaki 
Published: May 2009

Object. The segmental-type of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine is distinct from other types in its morphological features. Whether the results of expansive open-door laminoplasty for the segmental-type are different from those for other types remains unclear. To clarify this issue, the long-term results after surgical treatment of segmental-type OPLL were compared with those of other types.
Methods. Clinical results were documented in 57 patients who underwent expansive open-door laminoplasty and were followed for a minimum of 7 years, results were quantified using the Japanese Orthopaedic Association (JOA) scoring system to determine function. Segmental-type OPLL was observed in 10 patients (Group 1) and other types in 47 patients (Group 2). Preoperative JOA scores were not significantly different between the two groups. As many as 5 years after surgery, clinical results were favorable and maintained in both groups, and no significant intergroup difference in postoperative JOA scores was observed; however, after 5 years postoperatively, JOA scores decreased in both groups. The decrease was greater in Group 1, and a significant intergroup difference in JOA scores was demonstrated when analyzing final follow-up data. In Group 1, the authors found that the degree of late-onset deterioration relating to cervical myelopathy positively correlated with the cervical range of motion.
Conclusions. The long-term results of expansive open-door laminoplasty in the treatment of segmental-type OPLL were inferior to those for other types. Cervical mobility may contribute to the development of late deterioration of cervical myelopathy.
Anterior decompression combined with corpectomies and discectomies in the management of multilevel cervical myelopathy: a hybrid decompression and fixation technique
Authors: Ashkenazi Ely , Smorgick Yossi , Rand Nahshon , Millgram Michael A. , Mirovsky Yigal , Floman Yizhar 
Published: May 2009

Object. The authors retrospectively evaluated the safety and efficacy of a decompression and fixation technique in the treatment of patients with multilevel cervical spondylotic myelopathy (CSM).
Methods. The authors describe the “hybrid decompression fixation” technique, a procedure involving a combination of corpectomies and discectomies to preserve a vertebra intact within the area of the decompression, thus augmenting mechanical stability. The authors retrospectively reviewed outcomes in 25 patients with multilevel CSM in whom the hybrid technique was performed between 1999 and 2003. Twelve patients underwent a single-level corpectomy and three-level discectomies. In 13 patients a two-level corpectomy and adjacent four-level discectomies were conducted, leaving a vertebral bridge the middle. All patients underwent fusion involving placement of disc and vertebral body cages filled with autogenous local bone and supplemental anterior dynamic plate fixation.
The mean preoperative Nurick grade was 3 and improvement in status was reflected by a postoperative decrease to 2.6 (p < 0.05). In one patient neurological deterioration was demonstrated. At the end of the follow-up period (mean 29 months) radiography revealed evidence of osseous fusion in 24 patients; fusion status could not be determined in one patient. No evidence of late-onset instrumentation-related failure was observed in any of the 25 patients.
Conclusions. The authors found the hybrid technique to be safe and efficient for anterior decompression in patients with multilevel CSM. The use of this technique obviates the need for staged circumferential procedures.
Radiculopathy of C-5 after anterior decompression for cervical myelopathy
Authors: Ikenaga Minoru , Shikata Jitsuhiko , Tanaka Chiaki 
Published: May 2009

Object. The authors conducted a study to examine the incidence and causes of postoperative C-5 radiculopathy, and they suggest preventive methods for C-5 palsy after anterior corpectomy and fusion.
Methods. The authors included in the study 18 patients with postoperative C-5 radiculopathy from 563 patients who underwent anterior decompression and fusion for cervical myelopathy.
There were 10 cases of ossification of the posterior longitudinal ligament (OPLL) and eight cases of cervical spondylotic myelopathy (CSM). All patients received conservative treatment. Posttreatment full recovery was present in eight patients, and Grade 3/5 strength was documented in six in whom some weakness remained.
Radiographic evaluation revealed that the C3–4 and C4–5 cord compression was significantly more severe in patients with paralysis than in those without paralysis. The incidence of paralysis was higher in patients with OPLL than in those with CSM (chi-square test, p = 0.03). The incidence of paralysis increased in parallel with the number of fusion levels (correlation coefficient r = 0.94). Multivariate analysis revealed that the final manual muscle testing (MMT) value was closely related to the preoperative MMT value (computed t value 4.17; p < 0.01) and preoperative Japanese Orthopaedic Association (JOA) score for cervical myelopathty (computed t value, 2.75; p < 0.05).
Conclusions. Preexisting severe stenosis at C3–4 or C4–5 in patients with OPLL is a risk factor for paralysis. Preoperative muscle weakness and a low JOA score are factors predictive of poor recovery.
Minimally invasive transforaminal lumbar interbody fusion with ipsilateral pedicle screw and contralateral facet screw fixation
Authors: Jang Jee-Soo , Lee Sang-Ho 
Published: May 2009

Object. The purpose of this study was to introduce a minimally invasive transforaminal lumbar interbody fusion (TLIF) technique that involves ipsilateral pedicle screw (PS) and contralateral facet screw (FS) fixation.
Methods. Eight men and 15 women (mean age 59.5 years, range 48–68) underwent the aforementioned TLIF procedure for degenerative spondylolisthesis and uni- or bilateral radiculopathy.
Twenty-two patients underwent one-level fusion and one patient two-level fusion (L4—S1). In all cases the various procedures were undertaken via one small incision. There were no intraoperative complications. The mean estimated blood loss (EBL) was 310 ml, and the mean operative time was 150 minutes in cases of one-level fusion.
The follow-up period ranged from 13 to 28 months (mean 19 months). The mean Numeric Rating Scale score reflected improvement-reductions from 7.5 (back pain) and 7.4 (leg pain) to 2.3 and 0.7, respectively (p < 0.0001). The mean Oswestry Disability Index (ODI) scores also reflected improved status (ODI of 33.1 before the surgery to 7.6 after the surgery; p < 0.0001). Examination indicated that 22 of 24 fusion sites exhibited osseous union. At the last follow-up examination, satisfactory outcomes were observed in 21 out of 23 patients.
Conclusions. The TLIF with ipsilateral PS and contralateral FS fixation has the advantages over the conventional TLIF of reduced EBL and diminished soft-tissue injury.