bluuebunny/crossref_metadata_2025_split huggingface dataset:
Degenerative lumbar spondylolisthesis—induced radicular compression: nonfusion-related decompression in selected patients without hypermobility on flexion—extension radiographs
Authors: Kristof Rudolf A. , Aliashkevich Ales F. , Schuster Michael , Meyer Bernhard , Urbach Horst , Schramm Johannes 
Published: May 2009

Object. The authors conducted a study to determine the results of decompressive surgery without fusion in selected patients who presented with radicular compression syndromes caused by degenerative lumbar spondylolisthesis and in whom there was no evidence of hypermobility on flexion—extension radiographs.
Methods. The medical records and radiographs obtained in 49 patients were reviewed retrospectively. Clinical status was quantified by summing self-assessed Prolo Scale scores. All 49 patients (55% female, mean age 68.7 years) presented with leg pain accompanied by lumbalgia in 85.7% of the cases. Preoperatively the median sum of Prolo Scale scores was 4. The mean preoperative degree of forward vertebral displacement was 13.5% and was located at L-4 in 67% of the cases. Osseous decompression alone was performed in 53%, and an additional discectomy at the level of displacement was undertaken in the remaining patients because of herniated discs. Major complications (deep wound infection) occurred in 2%. During a mean follow-up period of 3.73 years, 10.2% of the patients underwent instrumentation-assisted lumbar fusion when decompression alone failed to resolve symptoms. At last follow up the median overall Prolo Scale score was 8. Excellent and good results were demonstrated in 73.5% of the patients. Prolonged back pain (r = 0.381) as well as the preoperative degree of displacement (r = 0.81) and disc space height (r = 0.424) influenced outcome (p ≤ 0.05); additional discectomy for simultaneous disc herniation at the displaced level did not influence outcome (p > 0.05).
Conclusions. These results appear to support a less invasive approach in this subgroup of elderly patients with degenerative lumbar spondylolisthesis—induced radicular compression syndromes and without radiographically documented hypermobility. Additional discectomy for simultaneous disc herniation of the spondylolisthetic level did not adversely influence the outcome. Complication rates are minimized and fusion can eventually be performed should decompression alone fail. A prospective controlled study is required to confirm these results.
Percutaneous transpedicular vertebroplasty with calcium phosphate cement in the treatment of osteoporotic vertebral compression and burst fractures
Authors: Nakano Masato , Hirano Norikazu , Matsuura Kousou , Watanabe Hiroki , Kitagawa Hideki , Ishihara Hirokazu , Kawaguchi Yoshiharu 
Published: May 2009

Object. Osteoporotic vertebral fractures occasionally lead to late-onset collapse, kyphosis, persistent back pain, and disability. The authors describe a series of patients in whom they performed percutaneous vertebroplasty by using calcium phosphate cement (CPC) to obtain early pain relief and improve the integrity of the osteoporotic vertebral body (VB).
Methods. Between August 2000 and February 2001, they performed 17 percutaneous transpedicular CPC-assisted vertebroplasty procedures in 16 patients who harbored thoracic or lumbar osteoporotic vertebral fractures. Following repositioning and curettage of the pathological soft tissues, CPC-assisted vertebroplasty was percutaneously performed in four patients with osteoporotic burst fracture and pseudarthrosis (Procedure A). In situ CPC-assisted vertebroplasty was performed in 12 patients with fresh vertebral compression fractures due to osteoporosis (Procedure B). Back pain and low-back pain were evaluated using a visual analog scale (VAS). The deformity index of the VB was measured on a lateral radiograph as the ratio of the VB's height (sum of measurements at anterior, middle, and posterior regions) to its longitudinal diameter. Based on VAS scores, pain was decreased in all patients immediately after surgery, and pain relief was maintained at the last follow up. The mean preoperative deformity index score of the VB was 1.43 in Procedure A and 1.67 in Procedure B; postoperatively scores improved to 1.59 and 1.93, respectively. At the 6-month follow-up examination, the mean deformity index score rebounded to 1.52 in Procedure A and 1.79 in Procedure B. Bone union was documented in all patients. Complications, such as a temporary respiratory insufficiency and a small amount of CPC leakage into the spinal canal, were observed in patients who underwent Procedure B.
Conclusions. Percutaneous transpedicular CPC-assisted vertebroplasty is a minimally invasive procedure that provides early relief of pain and prevents vertebral collapse and pseudarthrosis in patients with osteoporotic vertebral fracture.
Hydroxyapatite laminar spacers and titanium miniplates in cervical laminoplasty
Authors: Goto Takeo , Ohata Kenji , Takami Toshihiro , Nishikawa Misao , Tsuyuguchi Naohiro , Morino Michiharu , Matusaka Yasuhiro , Nishio Akimasa , Inoue Yuichi , Hara Mitsuhiro 
Published: May 2009

Object. The authors describe a new surgical technique for cervical laminoplasty that was performed in 25 patients. The posterior elements along with the various ligaments are removed en bloc and are stabilized in a lift-up position by placing hydroxyapatite (HA) laminar spacers and titanium miniplates and screws. The procedure and clinical results are discussed.
Methods. The posterior spinal elements, including the lamina(e), spinous process(es), and various attached ligaments, are removed en bloc by incising the lamina in its lateral aspect. Trapezoid-shaped HA spacers are placed between the cut ends of the laminae or between the laminae and lateral masses bilaterally at each level. Malleable titanium miniplates and screws are used for fixation of the spacers. The fixation of transected laminae was judged to be successful. Postoperative care included application of a soft neck collar for 1 week but no further restriction of activity. Surgery-related outcome was assessed in the 21 patients who attended more than 6 months of follow up after laminoplasty. There were 18 men and three women who ranged in age from 27 to 81 years. Cervical stenotic myelopathy was demonstrated in 15 patients who underwent decompressive and expansive laminoplasty, and spinal tumors were documented in six patients who underwent a nonexpansive laminoplasty. Postoperative and follow-up computerized tomography scans demonstrated no hardware failure. Bone formation around the spacers was observed either at 6- or at 9-month follow-up examination in all 21 patients. Fusion of the reconstructed laminae was found to be completed at 12 months in all 18 patients able to attend follow up for this duration. Spinal alignment and the range of motion of the cervical spine were well preserved. In patients with stenotic cervical myelopathy, neurological and anatomical outcome of canal expansion were satisfactory.
Conclusions. This technique enables rigid laminoplasty while maintaining anatomical and biomechanical integrity of posterior elements of cervical spine. Expansive and nonexpansive laminoplasty procedures are possible.
Biomechanical properties of expander compared with conventional screws
Authors: Rassi-Neto Aziz , Shimano Antonio 
Published: May 2009

Object. A pullout strength biomechanical study was performed in 20 fresh swine vertebral bodies in which titanium expander (Group 1) and conventional screws (Group 2) were placed.
Methods. The screws were inserted into the anterosuperior portion of the anterior spine, and assessment was performed after application of loads. The expander screw is composed of two parts: 1) a cover with an external portion comprising tight thin threads; and 2) a compact internal screw inserted through the cover that allows expansion. In the comparative study between the screws in Groups 1 and 2 maximum load was assessed, and the intergroup difference was significant (p = 0.00001 [t-test]); regarding load at the elasticity threshold, a significant difference was also observed (p = 0.0063). With regard to rigidity (stiffness), there was a tendency in both groups toward significance (p = 0.069). With regard to absorbed energy in the elastic phase, statistical analysis showed a significant intergroup difference (p = 0.00439). The expander screw showed a greater load-bearing capacity than the conventional screw. Adhesion to bone in relation to the applied load and displacement was greater (significant tendency) in the expander screw group than in the conventional screw group.
Conclusions. The expander screws exhibited a greater capacity to absorb energy in the elastic phase. They adhered better to bone, were easy to insert, and, if necessary, were simple to remove.
Thoracic idiopathic spinal cord herniation at the vertebral body level: a subgroup with a poor prognosis?
Authors: Barbagallo Giuseppe M. V. , Marshman Laurence A. G. , Hardwidge Carl , Gullan Richard W. 
Published: May 2009

✓ The authors present two cases of thoracic idiopathic spinal cord herniation (TISCH) occurring at the vertebral body (VB) level in whom adequate surgical reduction failed to reverse symptoms. In the second case, in which TISCH occurred into a VB cavity, presentation was atypical (subacute spinal cord syndrome) and there was persistent postoperative deterioration.
In both cases, adequate surgical reduction was achieved via a posterior midthoracic laminectomy, and reduction was maintained by closure of the anterior dural defect by using prosthetic material.
Thoracic idiopathic spinal cord herniation occurring at a VB level may be technically well treated by surgical reduction, but the outcome appears less predictable. Herniation that occurs directly into a VB cavity may form a distinct subgroup in which the presentation is atypical and the prognosis worse.
Use of polylactide resorbable film as an adhesion barrier
Authors: Welch William C. , Thomas Kevin A. , Cornwall G. Bryan , Gerszten Peter C. , Toth Jeffrey M. , Nemoto Edwin M. , Turner A. Simon 
Published: May 2009

Object. The present investigation evaluates two thicknesses of a resorbable polylactic acid (PLA) barrier film as an adhesion barrier to posterior spinal scar formation.
Methods. A readily contourable, thin film was placed directly over the dura. The thick film was placed above the lamina defect to act as a physical barrier inhibiting the prolapse of soft tissue into the epidural space. Through a combination of gross dissection with and without scar scores, quantitative analysis of collagen adjacent to the scar site, and histological evaluation, the resorbable adhesion barrier membranes were found to be effective treatment for reduction of posterior adhesions.
Conclusions. The gross dissection demonstrated that both thicknesses of resorbable PLA barrier films created a controlled dissection plane, facilitated access to the epidural space, and provided a reduction in the tissue adherent to the dura.
Evaluation of 70/30 poly (l-lactide-co-d,l-lactide) for use as a resorbable interbody fusion cage
Authors: Toth Jeffrey M. , Estes Bradley T. , Wang Mei , Seim Howard B. , Scifert Jeffrey L. , Turner A. Simon , Cornwall G. Bryan 
Published: May 2009

Object. Titanium lumbar interbody spinal fusion devices are reported to be 90% effective in cases requiring single-level lumbar interbody arthrodesis, although radiographic determination of fusion has been debated.
Methods. Using blinded radiographic, biomechanical, histological, and statistical measures, researchers in the present study evaluated a radiolucent 70/30 poly(l-lactide-co-d,l-lactide) interbody fusion device packed with autograft or recombinant human bone morphogenetic protein—2 on a collagen sponge in 25 sheep at 3, 6, 12, 18, and 24 months. A trend of increased fusion stiffness, radiographic fusion, and histologically confirmed fusion was demonstrated at 3 months to 24 months postimplantation. Device degradation was associated with a mild to moderate chronic inflammatory response at all postoperative sacrifice times.
Conclusions. Use of this material in interbody fusion may be a viable alternative to metals.
Resorbable posterolateral graft containment in a rabbit spinal fusion model
Authors: Poynton Ashley R. , Zheng Fengyu , Tomin Emre , Lane Joseph M. , Cornwall G. Bryan 
Published: May 2009

Object. The authors studied the effect of a resorbable graft containment device in a rabbit posterolateral lumbar spinal fusion model.
Methods. Twenty rabbits were divided into four groups: autologous bone graft (ABG), ABG with the MacroPore containment device (ABG + MP), demineralized bone matrix (DBM), and DBM with the containment device (DBM + MP). Fusion mass was assessed at 6 weeks with high-resolution radiography and volumetric computerized tomography. The graft containment device was associated with alteration of the fusion mass structure and significant enhancement of fusion mass volume (ABG versus ABG + MP, p = 0.027; DBM versus DBM + MP, p = 0.043).
Conclusions. A bioabsorbable protective graft containment device successfully enhanced posterolateral spinal fusion mass volume.
Use of a bioabsorbable anterior cervical plate in the treatment of cervical degenerative and traumatic disc disruption
Authors: Vaccaro Alexander R. , Carrino John A. , Venger Benjamin H. , Albert Todd , Kelleher Peter M. , Hilibrand Alan , Singh Kush 
Published: May 2009

Object. Anterior cervical discectomy and fusion (ACDF) is a widely accepted treatment for anterior degenerative or traumatic instability of the cervical spine. To reduce or eliminate complications such as implant migration and failure, imaging degradation, and fusion stress shielding that are occasionally associated with spinal instrumentation, attention has been given to the use of bioresorbable anterior cervical plate (ACP) devices. This paper is a preliminary report of a retrospective series in which a resorbable mesh and screw system was used for graft containment in single-level ACDF.
Methods. A review of patient charts and imaging studies was conducted to determine functional outcome, fusion success, and potential soft-tissue reaction to implant resorption. Nine patients with a cervical degenerative disc disease or traumatic disc disruption were treated between October 2001 and March 2002. Follow up averaged 206 days. Eight patients were found to have an excellent result, one patient had a good result, and no patients had a satisfactory or poor result. At the time of follow-up examination, 77% of patients were found to have a radiographically solid fusion. The two patients without a solid fusion were examined only an average 8 months postoperatively and manifested no symptoms related to fusion nonhealing. No significant soft-tissue reaction was noted clinically or radiographically in any of the patients.
Conclusions. The results of this preliminary study indicate that bioresorbable ACP systems for single-level ACDF are both safe and effective.
Ventral correction of postsurgical cervical kyphosis
Authors: Steinmetz Michael P. , Kager Christopher D. , Benzel Edward C. 
Published: May 2009

Object. Cervical kyphotic deformation may develop after surgery involving either the ventral or dorsal approach. Regardless of the cause, the development of a cervical kyphotic deformity should be avoided, if possible, and corrected if present, when appropriate. The authors describe their experience with a technique for the ventral correction of iatrogenic (postoperative) cervical kyphosis.
Methods. A retrospective review of cases involving correction of postoperative iatrogenic cervical kyphosis via an ventral approach was performed. The authors conducted an ventral approach to kyphosis correction. The procedure required specific head positioning (in extension), convergent distraction pins, and an ventrally placed implant (axially dynamic when appropriate) with multiple points of fixation including at least one point of intermediate fixation. The pre- and postoperative sagittal angle and clinical status were evaluated.
During a nearly 14-month period, 12 patients met the inclusion criteria. Ten patients underwent a minimum of 6 months of follow up. They comprised the study population. Most patients presented with mechanical neck pain as part of their symptom profile. The mean magnitude of deformity correction (pre- to postoperative) was 20° of lordosis. The mean postoperative sagittal angle was 6° of lordosis. The mean change in the sagittal angle during the follow-up period was 2.2° of lordosis.
Conclusions. The ventral approach to correction of cervical deformity led to the achievement of lordosis in all but one patient. This posture was effectively maintained during the follow-up period. All patients exhibited improvement postoperatively; three experienced complete resolution of their preoperative symptoms. When symptoms are related to postsurgical kyphosis, deformity correction should be considered. Such a procedure may be performed effectively via an ventral approach in most circumstances.
Percutaneous vertebroplasty and kyphoplasty for painful vertebral body fractures in cancer patients
Authors: Fourney Daryl R. , Schomer Donald F. , Nader Remi , Chlan-Fourney Jennifer , Suki Dima , Ahrar Kamran , Rhines Laurence D. , Gokaslan Ziya L. 
Published: May 2009

Object. The current North American experience with minimally invasive vertebro- and kyphoplasty is largely limited to the treatment of benign osteoporotic compression fractures. The objective of this study was to assess the safety and efficacy of these procedures for painful vertebral body (VB) fractures in cancer patients.
Methods. The authors reviewed a consecutive group of cancer patients (21 with myeloma and 35 with other primary malignancies) undergoing vertebro- and kyphoplasty at their institution. Ninety-seven (65 vertebro- and 32 kyphoplasty) procedures were performed in 56 patients during 58 treatment sessions. The mean patient age was 62 years (± 13 years [standard deviation]) and the median duration of symptoms was 3.2 months. All patients suffered intractable spinal pain secondary to VB fractures.
Patients noted marked or complete pain relief after 49 procedures (84%), and no change after five procedures (9%); early postoperative Visual Analog Scale (VAS) pain scores were unavailable in four patients (7%). No patient was worse after treatment. Reductions in VAS pain scores remained significant up to 1 year (p = 0.02, Wilcoxon signed-rank test). Analgesic consumption was reduced at 1 month (p = 0.03, Wilcoxon signed-rank test). Median follow-up length was 4.5 months (range 1 day–19.7 months). Asymptomatic cement leakage occurred during vertebroplasty at six (9.2%) of 65 levels; no cement extravasation was seen during kyphoplasty. There were no deaths or complications related to the procedures. The mean percentage of restored VB height by kyphoplasty was 42 ± 21%.
Conclusions. Percutaneous vertebro- and kyphoplasty provided significant pain relief in a high percentage of patients, and this appeared durable over time. The absence of cement leakage—related complications may reflect the use of 1) high-viscosity cement; 2) kyphoplasty in selected cases; and 3) relatively small 3volume injection. Precise indications for these techniques are evolving; however, they are safe and feasible in well-selected patients with refractory spinal pain due to myeloma bone disease or metastases.
Safety of supplemental endplate screws in thoracic pedicle hook fixation
Authors: Cohen-Gadol Aaron A. , Dekutoski Mark B. , Kim Choll W. , Quast Lynn M. , Krauss William E. 
Published: May 2009

Object. The AO Universal Spine System thoracic pedicle hook design includes a fixation screw that passes obliquely through the inferior facet into the pedicle to engage in the posterior portion of the superior vertebral body endplate. This endplate screw provides additional purchase at the hook—bone interface. To determine the safety of this fixation system the authors reviewed the operative notes, radiographs, and outcomes of patients who underwent placement of endplate screws.
Methods. Thirty-six patients (16 male and 20 female patients) who required posterior thoracic instrumentation for spinal deformity (11 cases), neoplasm (15 cases), and traumatic injury (10 cases) were included in this study.
One hundred sixty-four endplate screws were placed (mean 4.3/patient) to augment pedicle hooks for posterior thoracic instrumentation. The number of instrumented levels ranged from seven to 16. The positions of the screws in relation to the pedicle, neural foramen, spinal canal, and endplate were evaluated by assessing plain radiographs and computerized tomography scans (10 cases). Eighty-two screws (56%) were in ideal position. Lateral pedicle wall perforation occurred with 51 screws (35%). Three screws violated the medial wall and nine screws violated the superior or inferior walls of the pedicle. There were no clinical sequelae associated with any of the malpositioned screws. Adequate follow-up radiographic data were not available in five patients. The mean follow-up duration was 19.8 months (range 3–61 months).
Two patients required revision surgery at 3 months and 18 months, respectively, because of hook/endplate screw displacement. There was also one case of an endplate screw fracture without hook displacement that was discovered during subsequent revision surgery. The remainder of the endplate screws and associated pedicles hooks maintained their original positions. There was no case of spinal cord, nerve root, pulmonary, or vascular injury.
Conclusions. The placement of supplemental endplate screws in conjunction with thoracic pedicle hooks can be conducted safely.
Balloon kyphoplasty: one-year outcomes in vertebral body height restoration, chronic pain, and activity levels
Authors: Ledlie Jon T. , Renfro Mark 
Published: May 2009

Object. The authors assessed the safety of balloon kyphoplasty in the reduction and repair of osteopenic vertebral compression fractures and report functional outcomes (back pain and activity levels) in the first 96 patients (with 133 fractures) at their institution. Additionally they provide radiographic outcomes in the first 26 patients (41 fractures) treated and followed for 1 year.
Methods. The authors conducted a retrospective chart review of functional outcomes and evaluated radiographs obtained at 1 week, 1 month, 3 months, 6 months, and 1 year postoperatively.
Conclusions. Balloon kyphoplasty safely increases vertebral body height, decreases chronic back pain, and quickly returns geriatric patients to higher activity levels, leading to increased independence and quality of life.