bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of spinal disease on successful arthrodesis in lumbar pedicle screw fixation
Authors: Narayan Prithvi , Haid Regis W. , Subach Brian R. , Comey Christopher H. , Rodts Gerald E. 
Published: May 2009

Object. Pedicle screw fixation with transverse process fusion has gained widespread acceptance since its inception. Improved rates of arthrodesis have been demonstrated when this technique is used. The authors present one of the largest series of patients to undergo this procedure at a single center; one of the goals was to correlate construct length and spinal disease with rates of successful arthrodesis by conducting a prospective analysis of lumbar fusion in which pedicle screws were placed.
Methods. During a 7-year period, the senior author performed pedicle screw fixation with posterolateral fusion in 457 patients; the mean follow-up period was 28.4 months. Indications for fusion included metastatic tumor, single-level degenerative disc disease (DDD), trauma, degenerative scoliosis, and translational vertebral instability. Successful fusion was based on the radiographic demonstration of a bilateral contiguous osseous bridge over the transverse processes and absence of movement on dynamic x-ray films.
Fusion rates were lowest in cases of tumors (54%) and highest in cases of trauma (96%). In patients with single-level DDD the rate was 91%, and in those with translational instability it was 89%. Fusion rates, however, declined steeply in relation to each additional motion segment in the translational instability group. In this group a strong linear trend for proportion was demonstrated (p < 0.001). The overall fusion rate in patients with degenerative scoliosis was 70%. The overall fusion rate for the entire group was 86%.
Conclusions. The data in this study can be used as a benchmark with which to compare newer technologies. Although overall pedicle screw—assisted fusion rate in cases of trauma or selected degenerative lesions approached 90%, the arthrodesis rates are not uniform for the different diagnoses. This appears to be related to the underlying spinal disease and the number of segments included in the fusion.
Surgical treatment of superior sulcus tumors with spinal and brachial plexus involvement
Authors: Bilsky Mark H. , Vitaz Todd W. , Boland Patrick J. , Bains Manjit S. , Rajaraman Viswanathan , Rusch Valerie W. 
Published: May 2009

Object. Non—small cell lung carcinomas with spinal and brachial plexus involvement have traditionally been considered to be Stage IIIb lesions and therefore unresectable. Advances in spinal surgery, the application of magnetic resonance (MR) imaging, and improvements in neoadjuvant therapy require a reassessment of the potential for complete resection.
Methods. The authors conducted a retrospective review of all procedures involving the resection of superior sulcus tumors with spinal or brachial plexus involvement performed between 1985 and 1999. Assessment or resectability and operative planning were based on an MR imaging classification scheme in which the extent of spinal involvement was considered. Class A tumors involved the periosteum of the vertebral body (VB) (16 patients); Class B, distal neural foramen without epidural compression (eight patients); Class C, proximal neural foramen with epidural compression (four patients); and Class D, bone involvement (VB or posterior elements) with or without epidural involvement (14 patients). Brachial plexus involvement was present in 21 patients, including 17 with T-1 nerve root only and four with C-8 or lower-trunk infiltration.
Complete tumor resection was achieved in 27 patients and incomplete resection in 15. Complications occurred in 14 patients, two of which were related to instrumentation failures. The overall median survival was 1.44 years. The median survival for the complete and incomplete resection groups were 2.84 and 0.79 years, respectively (p = 0.0001). There was no statistical difference in survival among classification groups.
Conclusions. Complete tumor resection of superior sulcus tumors is possible in selected patients in whom involvement of the spinal column and/or brachial plexus is present. Preoperative MR imaging is essential for evaluation of the spine and surgical planning. Survival and cure are dependent on complete resection, regardless of the extent of spinal involvement.
Relationship between alignment of upper and lower cervical spine in asymptomatic individuals
Authors: Nojiri Kenya , Matsumoto Morio , Chiba Kazuhiro , Maruiwa Hirofumi , Nakamura Masaya , Nishizawa Takashi , Toyama Yoshiaki 
Published: May 2009

Object
The aim of this study was to establish standard values for the normal alignment of the upper cervical spine and to clarify its relationship with the lower cervical spine in terms of alignment.

Methods
Three hundred thirteen asymptomatic volunteers (155 men and 158 women) participated in this study. Lateral radiographs were obtained with the neck in neutral position, and the angles formed by the occiput (Oc) and the axis, the atlas and the axis, and C-2 to C-7 were measured. The mean Oc—C2 angle was 14.5 ± 8° in men and 16 ± 8.5° in women; the mean C1–2 angle was 26.5 ± 7° and 28.9 ± 6.7°, respectively; and the mean C2–7 angle was 16.2 ± 12.9° and 10.5 ± 10.3°, respectively. Although weak, statistically significant negative correlation was observed between Oc—C2 and C2–7 angles (r = −0.31 in men and −0.37 in women), and between C1–2 and C2–7 angles (r = −0.22 in men and −0.22 in women). The correlation coefficient between the Oc—C2 and C2–7 angles was greater than that between the C1–2 and C2–7 angles.

Conclusions
Such relationships between alignment of the upper and lower cervical spines should be taken into consideration when performing occipitocervical fusion.
Anterior cervical plate fixation: biomechanical effectiveness as a function of posterior element injury
Authors: Pitzen Tobias , Lane Chris , Goertzen Darrell , Dvorak Marcel , Fisher Charles , Barbier Dragos , Steudel Wolf-Ingo , Oxland Thomas 
Published: May 2009

Object
The primary goal of this study was to determine if the stabilization provided to the spine by anterior cervical fixation with plating (ACFP) was dependent on the degree of posterior element injury. The secondary goal was to evaluate the effectiveness of additional posterior screw/rod stabilization in these injuries.

Methods
Following ACFP with interbody bone graft and stepwise transection of the posterior ligaments and facets at C5–6, eight fresh-frozen human C4–7 spine segments were loaded using pure moments of ± 1.5 Nm in flexion—extension, axial rotation, and lateral bending in the intact state. Posterior screw/rod fixation was performed after complete ligamentous destruction and complete removal of the facets. Repeated-measures analysis of variance and pairwise Student-Newman-Keuls tests were used to detect changes in the range of motion (ROM) and neutral zone (NZ). Statistical significance was assumed at a 95% level.
Significant increases in ROM occurred in each loading direction after transection of the capsular ligaments (p < 0.001) and again following facetectomy (p < 0.001) compared with the ACFP condition. Additional posterior fixation resulted in a significant decrease in ROM in all loading directions (p < 0.001). There was a significant increase in NZ for complete ligamentous destruction compared with ACFP (p < 0.05) and facetectomy compared with ACFP (p < 0.05) for flexion—extension. In lateral bending, a significant increase in NZ was found for facetectomy compared with ACFP (p < 0.05).

Conclusions
Capsular ligaments and articular facets are important structures in limiting three-dimensional vertebral motion in the presence of an anterior plate. Supplementary posterior fixation does reduce motion for all injury conditions.
Transarticular screw fixation in the middle and lower cervical spine
Authors: Takayasu Masakazu , Hara Masahito , Yamauchi Katsuaki , Yoshida Mitsuhiro , Yoshida Jun 
Published: May 2009

✓ Although atlantoaxial transarticular screw fixation is technically demanding and there is a significant risk of vertebral artery (VA) injury, transarticular screw insertion in the middle and lower cervical spine is simple and can be performed safely with the aid of lateral fluoroscopic guidance. The authors describe the surgical techniques and outcome of transarticular screw fixation in the middle and lower cervical spine.
Transarticular screw insertion into C2–3 or caudal cervical joints was performed from the articular pillar, directing the screw anterocaudally to penetrate the facet joint and the anterior cortex of the articular pillar, parallel to the sagittal plane. Because the VA and the nerve roots are anterior to the articular pillar at these levels, the screw can be placed safely with the assistance of lateral fluoroscopic guidance. Twenty-five patients ranging in age from 15 to 84 years underwent transarticular screw fixation, with a total of 81 screws. The transarticular screw was used as an anchor screw in combination with posterior cervical instrumentation in 19 patients and for facet screw fixation itself in six patients. Screw placement was successful and uncomplicated in all cases. The follow-up period ranged from 3 months to 5 years. No instance of screw backout or loosening was identified radiographically; fusion was achieved in all patients. Biomechanical strength is maintained by penetrating four cortical layers. When performed appropriately, this method is safe and reliable and deserves more widespread use.
Outcome evaluation of the operative management of lumbar disc herniation causing sciatica
Authors: Fisher Charles , Noonan Vanessa , Bishop Paul , Boyd Michael , Fairholm David , Wing Peter , Dvorak Marcel 
Published: May 2009

Object. The authors conducted a study to assess health-related quality of life (HRQOL) and the appropriateness of surgery in patients who have undergone elective lumbar discectomy.
Methods. The study involved a prospective cohort of 82 surgically treated patients with lumbar disc herniation causing lower-extremity radiculopathy. An independent study coordinator recorded demographic data and administered the North American Spine Society (NASS) lumbar spine instrument and the Short Form—36 (SF-36) before treatment, and at 6 months and 1 year after surgery. The HRQOL results were also compared with normative data for the NASS and SF-36. The influence of baseline variables on HRQOL was determined using regression modeling. The InterQual Indicators for Surgery and Procedures (ISP) were used to compare surgeon practice patterns with standardized indications for surgery.
The NASS neurogenic symptom (NSS) and pain/disability scores (PDSs) showed very significant improvement at 6 months and little change between 6 months and 1 year. The SF-36 physical function and bodily pain scale scores were associated with the greatest improvement. Interestingly, the 1-year NASS (NSS and PDS) and SF-36 (only PCS) scores remained lower than those of age-matched normative data. Other than preoperative HRQOL scores, the only other variable that inversely influenced HRQOL was the duration of time between symptom onset and surgery. Ninety-five percent of ISP forms were completed, and 97% of the indications recorded by the surgeon matched the criteria.
Conclusions. The reporting of standardized outcomes in association with indications for surgery is feasible and may help elucidate the ideal rate for discectomy.
Two-year observation of artificial intervertebral disc replacement: results after supplemental ultra—high strength bioresorbable spinal stabilization
Authors: Kotani Yoshihisa , Abumi Kuniyoshi , Shikinami Yasuo , Takahata Masahiko , Kadoya Ken , Kadosawa Tsuyoshi , Minami Akio , Kaneda Kiyoshi 
Published: May 2009

Object. This 2-year experimental study was conducted to investigate the efficacy of a bioactive three-dimensional (3D) fabric disc for lumbar intervertebral disc replacement. The authors used a bioresorbable spinal fixation rod consisting of a forged composite of particulate unsintered hydroxyapatite/poly-l-lactide acid (HA/PLLA) for stability augmentation. The biomechanical and histological alterations as well as possible device-related loosening were examined at 2 years postoperatively.
Methods. Two lumbar intervertebral discs (L2–3 and L4–5) were replaced with the 3D fabric discs, which were augmented by two titanium screws and a spanning bioresorbable rod (HA/PLLA). The segmental biomechanics and interface bone ingrowth were investigated at 6, 15, and 24 months postoperatively, and results were compared with the other two surgical groups (3D fabric disc alone; 3D fabric disc with additional anterior instrumentation stabilization). The 3D fabric disc and HA/PLLA—spinal segments demonstrated segmental mobility at 15 and 24 months; however, the range of motion (ROM) in flexion—extension decreased to 49 and 40%, respectively, despite statistically equivalent preserved torsional ROM. Histologically there was excellent osseous fusion at the 3D fabric disc surface—vertebral body interface. At 2 years posttreatment, no adverse tissue reaction nor aseptic loosening of the device was observed.
Conclusions. Intervertebral disc replacement with the 3D fabric disc was viable and when used in conjunction with the bioresorbable HA/PLLA spinal augmentation. Further refinements of device design to create a stand-alone type are necessary to obviate the need for additional spinal stabilization.
Total spondylectomy for en bloc resection of lung cancer invading the chest wall and thoracic spine
Authors: Komagata Masashi , Nishiyama Makoto , Imakiire Atshuhiro , Kato Hirobumi 
Published: May 2009

✓ Lung cancers invading the chest wall and spinal column are often considered unresectable, and consequently there are few reports describing resection of invasive vertebral lesions. The authors developed a new anterior approach procedure for the en bloc resection of primary lung adenocarcinoma invading the thoracic spine and chest wall, in which the primary tumor does not need to be separated from the vertebrae. The authors describe a total spondylectomy for the en bloc resection of lung cancer invading the spine. A combination of surgical techniques was required, including resection of the osseous elements T-2 and T-3 (the pedicles were excised using a thread saw), anterolateral thoracotomy, apical lobectomy, chest wall resection, vertebrectomy, anterior spinal column reconstruction with a titanium mesh cage containing bioactive glass ceramic, and placement of anterior and posterior spinal instrumentation. At 46 months after surgery, there is no evidence of local recurrence or distant metastasis, and the patient continues to improve.
This new procedure allows for the en bloc resection of primary lung tumors and adherent vertebral invasion without separation of the lesion from the vertebra. Thus, surgical management by complete excision of Pancoast tumors can achieve longer-term survival rates without sequelae.
Microsurgical infrapedicular paramedian approach for retrovertebral lumbar disc herniations
Authors: Hejazi Nedal 
Published: May 2009

✓ The author performed a microsurgical infrapedicular paramedian approach in 35 patients (23 men and 12 women) to remove herniated lumbar retrovertebral discs that did not have an apparent origin at either the superior or inferior disc level.
The goal of this surgery was to minimize the bone resection, preserve the facet joint, and avoid the risk of secondary vertebral instability. The Macnab outcome classification was used to assess all patients who attended follow-up examination for at least 15 months. The clinical results were excellent or good in 34 (97%) of 35 cases. This minimally invasive lumbar spine technique resulted in minimal morbidity, excellent clinical benefits, and a long-term outcome without evidence of secondary segmental instability.
Sciatica of nondisc origin and piriformis syndrome: diagnosis by magnetic resonance neurography and interventional magnetic resonance imaging with outcome study of resulting treatment
Authors: Filler Aaron G. , Haynes Jodean , Jordan Sheldon E. , Prager Joshua , Villablanca J. Pablo , Farahani Keyvan , Mcbride Duncan Q. , Tsuruda Jay S. , Morisoli Brannon , Batzdorf Ulrich , Johnson J. Patrick 
Published: May 2009

Object.Because lumbar magnetic resonance (MR) imaging fails to identify a treatable cause of chronic sciatica in nearly 1 million patients annually, the authors conducted MR neurography and interventional MR imaging in 239 consecutive patients with sciatica in whom standard diagnosis and treatment failed to effect improvement.Methods.After performing MR neurography and interventional MR imaging, the final rediagnoses included the following: piriformis syndrome (67.8%), distal foraminal nerve root entrapment (6%), ischial tunnel syndrome (4.7%), discogenic pain with referred leg pain (3.4%), pudendal nerve entrapment with referred pain (3%), distal sciatic entrapment (2.1%), sciatic tumor (1.7%), lumbosacral plexus entrapment (1.3%), unappreciated lateral disc herniation (1.3%), nerve root injury due to spinal surgery (1.3%), inadequate spinal nerve root decompression (0.8%), lumbar stenosis (0.8%), sacroiliac joint inflammation (0.8%), lumbosacral plexus tumor (0.4%), sacral fracture (0.4%), and no diagnosis (4.2%).Open MR—guided Marcaine injection into the piriformis muscle produced the following results: no response (15.7%), relief of greater than 8 months (14.9%), relief lasting 2 to 4 months with continuing relief after second injection (7.5%), relief for 2 to 4 months with subsequent recurrence (36.6%), and relief for 1 to 14 days with full recurrence (25.4%). Piriformis surgery (62 operations; 3-cm incision, transgluteal approach, 55% outpatient; 40% with local or epidural anesthesia) resulted in excellent outcome in 58.5%, good outcome in 22.6%, limited benefit in 13.2%, no benefit in 3.8%, and worsened symptoms in 1.9%.Conclusions.This Class A quality evaluation of MR neurography's diagnostic efficacy revealed that piriformis muscle asymmetry and sciatic nerve hyperintensity at the sciatic notch exhibited a 93% specificity and 64% sensitivity in distinguishing patients with piriformis syndrome from those without who had similar symptoms (p < 0.01).Evaluation of the nerve beyond the proximal foramen provided eight additional diagnostic categories affecting 96% of these patients. More than 80% of the population good or excellent functional outcome was achieved.
Unilateral removal of pars interarticularis
Authors: Tender Gabriel C. , Baratta Richard V. , Voorhies Rand M. 
Published: May 2009

Object. Lumbar radiculopathy secondary to foraminal entrapment can be treated by unilateral removal of the overlying pars interarticularis. The authors prospectively evaluated the outcome after this procedure.
Methods. Thirty-six consecutive patients underwent unilateral resection of the pars interarticularis between August 1999 and July 2002. In 18 patients acute foraminal disc herniations compressed the nerve root against the superior pedicle; in the other 18 foraminal stenosis was secondary to degenerative changes. All patients, at each visit, completed the following questionnaires: visual analog scale for overall, leg, and back pain; the Prolo Functional Economic Rating scale; and the Pain Rating Index (PRI) of the Short-Form McGill Pain Questionnaire.
At 1 year, leg pain improved in 33 patients (91%). Low-back pain appeared or worsened in eight patients (22%; one in the acute herniation group and seven in the chronic degenerative group). Only one patient required lumbar fusion for pain. The Prolo economic and function scores improved in 21 (58%) and 27 (75%) patients, respectively. The PRI scores improved in 30 cases (83%). No spondylolisthesis was observed at any level at which resection had been performed.
Conclusions. Unilateral removal of the pars interarticularis is effective in relieving lumbar radicular symptoms in patients with intraforaminal entrapment. The incidence of low-back pain in patients with acute foraminal disc herniations does not increase as a result of this procedure. In patients with degenerative foraminal stenosis, unilateral resection of the pars interarticularis may be a better alternative to facetectomy and segmental fusion. This procedure may be a useful tool in spine surgery.
Postoperative recovery of complete sudden paraplegia due to lumbar schwannoma
Authors: Mahadewa Tjokorda , Harsan Harsan , Nugroho Setyowidi , Bernstein Mark 
Published: May 2009

✓ The authors present a rare case of acute complete paraplegia due to a lumbar schwannoma. The clinical presentation, magnetic resonance imaging features, and management strategy are discussed.
A 29 year-old man presented with acute complete paraplegia and bladder and bowel incontinence. He had a history of stable back pain and a 4-year history of lower-extremity numbness bilaterally. Magnetic resonance imaging revealed an enhancing extraaxial mass filling the spinal canal over two segments below the conus medullaris. An L1–3 laminectomy was performed and the tumor was completely removed. Pathological evaluation showed features characteristic of a schwannoma. The patient regained almost complete motor function after 6 months.
To the authors' knowledge, this is the first reported case of acute complete paraplegia secondary to lumbar schwannoma. Possible mechanisms of this occurrence are discussed.
Thoracic transfacet pedicle screw fixation: a new instrumentation technique
Authors: Akbay Atilla , İnceoğlu Serkan , Milks Ryan , Schlenk Richard , Palaoglu Selcuk , Benzel Edward C. 
Published: May 2009

Object.Pedicle screw instrumentation of the thoracic spine remains technically challenging. Transverse process and costotransverse screw fixation techniques have been described as alternatives to pedicle screw fixation (PSF). In this study, the authors introduce thoracic transfacet PSF and compare its experimental biomechanical results with those of standard PSF in short-term cyclic loading in cadaveric thoracic specimens.Methods.Specimens were tested intact for six cycles at compressive loads of 250 N offset by 1 cm along appropriate axes to induce flexion, extension, and left and right lateral bending. The specimens were then fixed with either a pedicle screw/rod construct or transfacet pedicle screws and retested in the same fashion. After this sequence, specimens were loaded until failure in flexion mode at a rate of 5 mm/minute was observed.Both fixation constructs provided significantly greater stiffnesses than that demonstrated when the specimen was intact (p < 0.05, two-way analysis of variance). Additionally, the two constructs were statistically equivalent in terms of stiffness and load-to-failure values (p < 0.05, two-tailed nonpaired t-test). The only difference observed was that the low midthoracic region (T7–9) was biomechanically weaker than the upper midthoracic and lower thoracic areas in flexion after the destabilization and instrumentation-augmented stabilization procedures.Conclusions.In selected thoracic surgical procedures, transfacet PSF may, after analysis of long-term biomechanical data, potentially become a reasonable alternative to conventional PSF.