The Spine Journal - Articles in Press

Cervical nerve injection: computed tomography guidance with intravenous contrast and extraforaminal needle placement. Series of seven consecutive case reports - Corrected Proof

Charles H. Cho — 2010-03-02

Abstract: background context: Image-guided cervical nerve injections are being performed with increasing frequency. Severe complications are being reported.Purpose: The purpose of this study is to introduce a technique for cervical nerve injection that may decrease the possibility for severe complications.study design/setting: This is a series of case reports describing the technique and clinical follow-up.Patient sample: The sample comprises seven consecutive cases of unilateral neck and arm pain referred for cervical nerve injection.Outcome measures: Retrospective evaluation of pain relief before and after the injection and at follow-up is reported as case studies.Methods: The technique for computed tomography guided cervical nerve injection is described with case reports of seven consecutive patients.Results: The results are case reports of each of the seven patients after unilateral cervical nerve injection.Conclusion: A technique for cervical nerve injection is described with the results of the injection. This technique may allow some standardization in the procedure, decrease the learning curve for training physicians, and minimize the potential complications.

Isolated extraosseous epidural myeloma presenting with thoracic compressive myelopathy - Corrected Proof

Ashwin Avadhani, Ajoy P. Shetty, S. Rajasekaran — 2010-03-02

Abstract: Background context: Multiple myeloma is the commonest primary malignancy of the spine, but it rarely presents as an extraosseous epidural tumor with only five cases reported in literature so far.Purpose: The purpose of this study was to heighten awareness and treatment options of a rare case of extraosseous epidural myeloma.Study design: The study design comprises a case report and literature review.Methods: We present a 60-year-old lady with progressive paraplegia (American Spinal Injury Association grade C) with sensory blunting below T8 level of 2 months’ duration. Magnetic resonance imaging showed an extradural tumor in the dorsal epidural space from T6 to T7 without local bony involvement. She underwent a T6 and T7 laminectomy, T5–T8 pedicle screw instrumentation, and gross total resection of tumor. Histopathological diagnosis was consistent with myeloma. After surgery, the patient underwent local irradiation and adjuvant chemotherapy.Results: Neurological improvement of one grade (American Spinal Injury Association grade C to D) was observed at 3 weeks postoperatively.Conclusions: Isolated extraosseous epidural myeloma without destruction or collapse of vertebral bodies should be included in the differential diagnosis of epidural mass lesions causing spinal cord compression. The overall prognosis in terms of survival is poor, but early decompression can prevent neurological deterioration and improve quality of life.

Magnetic resonance imaging and stadiometric assessment of the lumbar discs after sitting and chair-care decompression exercise: a pilot study - Corrected Proof

Jerome C.J. Fryer, Jeffrey A. Quon, Francis W. Smith — 2010-03-02

Abstract: Background: Sitting is associated with loss of the lumbar lordosis, intervertebral disc (IVD) compression, and height loss, possibly increasing the risk of lower back pain. With a trend toward more sitting jobs worldwide, practical strategies for preventing lumbar flattening and potentially associated low back pain (LBP) are important.Purpose: The purpose of this study was to determine the feasibility of using upright magnetic resonance imaging (MRI) and stadiometry to measure changes in height and configuration of the lumbar spine before and after normal sitting and a seated unloading exercise intervention.Study Design/Setting: This is a hospital-based pilot study involving pre-post assessments in a single group.Patient Sample: The sample comprises six asymptomatic hospital employees involved in either general patient care or research writing/data collection.Outcome Measures: The outcome measures were lumbar total midsagittal cross-sectional IVD area, vertical height, lordotic angle derived from digitized MRI examinations, and seated body height measured directly with a stadiometer.Methods: Midsagittal MRI scans were performed before sitting, after 15 minutes of relaxed sitting (“postsitting”), immediately after seated unloading exercises, and approximately 7 minutes after exercise. Subsequently, seated stadiometry assessments were performed after 10 minutes of supine recumbency, 15 minutes of relaxed sitting, and every 10 seconds after seated unloading exercises until three consecutive height measurements were identical. Digitized midsagittal images were used to derive MRI-based outcome measures. Measurements at postsitting were compared with the corresponding ones at other time points using multiple paired t-tests. The Bonferroni method was used to adjust for multiple pairwise comparisons.Main Results: After 15 minutes of sitting, mean total IVD area, lordotic angle, and vertical height of the lumbar spine decreased 18.6 mm2, 6.2°, and 12.5 mm, respectively, whereas after seated unloading exercises, these parameters increased by 87.9 mm2, 5.0°, and 21.9 mm, respectively. Similarly, mean seated height on stadiometry decreased by 6.9 mm after 15 minutes of sitting and subsequently increased by 5.7 mm after unloading exercises.Conclusions: Seated upright MRI and stadiometry, as performed in this study, appear to be feasible methods for detecting compressive and decompressive spinal changes associated with normal sitting and, alternately, seated unloading exercises. Larger studies are encouraged to determine normative values of our study measurements and to determine if morphological changes induced by seated unloading predict treatment response and/or reductions in the incidence of sitting-related LBP.

Influence of needle type on the incidence of intravascular injection during transforaminal epidural injections: a comparison of short-bevel and long-bevel needles - Corrected Proof

Matthew Smuck, Andrew J. Yu, Chi-Tsai Tang, Eric Zemper — 2010-02-22

Abstract: Background context: Vascular penetration and injection of corticosteroids into a vessel during lumbosacral transforaminal epidural injection is a suspected cause of myelopathy. Blunt needles have been suggested to avoid vascular penetration, but they are difficult to navigate. Another alternative to the standard long-bevel sharp needles is the short-bevel needles. Some have postulated that short-bevel needles are the best option for high-risk spine injections because they maintain navigation characteristics while potentially reducing the risk of complications. To date, no studies have been performed to either confirm or refute this.Purpose: The purpose of this study was to determine if there is a difference in the incidence of vascular penetration during lumbosacral transforaminal epidural injections between short-bevel and long-bevel needles.Study design/setting: This is a prospective, observational, in vivo study.Patient sample: The sample comprises patients receiving lumbosacral transforaminal epidural injections at a university-based outpatient spine center.Outcome measure: The outcome measure was the incidence of vascular contrast patterns observed under live fluoroscopy.Methods: One interventional spine physician recorded contrast patterns observed during 158 fluoroscopically guided lumbosacral transforaminal epidural injections under live fluoroscopy using two different types of needle tips.Results: Vascular injections were observed in 22 of the 158 injections, for an overall incidence of 13.9%. The incidence of vascular injections in the short-bevel group was 15.6% (10/64) and in the long-bevel group was 12.8% (12/94). This difference was not statistically significant (p=.6447). A secondary analysis was performed to determine if the needle gauge influenced the incidence of vascular injections, and again, there were no statistical differences in the overall rates of vascular injection.Conclusions: In comparison with long-bevel needles, short-bevel needles do not reduce the risk of inadvertent vascular injection in lumbosacral transforaminal epidural injections.

Cryopreserved intervertebral disc with injected bone marrow–derived stromal cells: a feasibility study using organ culture - Corrected Proof

2010-02-22

Abstract: Background Context: A recent clinical study demonstrated that cryopreserved allogeneic intervertebral disc transplantation relieved pain and preserved motion, thus opening up a new treatment option for degenerative disc disease. However, these transplanted discs continued to degenerate, possibly due to a lack of viable cells. Bone marrow–derived stromal cell (BMSC) implantation has been shown to delay disc degeneration.Purpose: This study examined the viability over time of endogenous and injected BMSCs in cryopreserved disc under simulated-physiological loading conditions.Study Design/ Setting: An in vitro study of BMSCs injected into cryopreserved bovine caudal discs.Methods: Bovine caudal discs were harvested and cryopreserved at −196°C. After thawing, PKH-26–labeled BMSCs embedded in peptide hydrogel carrier were injected into the nucleus pulposus. Two BMSC injection quantities, that is, 1×105 and 2.5×105 were examined. Discs with injected cells were maintained in a bioreactor for 7 days under simulated-physiological loading. Cell viability (staining), gene expression (reverse transcription-polymerase chain reaction) profile, and proteoglycan content (histologically) were evaluated.Results: Forty percent of endogenous cell viability was maintained after freeze thawing. Over the 7-day culture, this did not change further. However, there was upregulation of Col1a2 and Mmp-13 and downregulation of Col2a1gene expression. Sixty percent of BMSCs survived the initial injection procedure, and only 20% remained alive after 7 days of culture. Bone marrow–derived stromal cell implantation did not alter the viability of the endogenous cells, but discs injected with 1×105 BMSCs showed significantly higher ACAN expression than sham discs.Conclusions: Although only 40% of cells survived cryopreservation, these endogeneous cells continued to survive over 7 days if maintained under simulated-physiological loading conditions. Although only a small portion of injected BMSCs survived, they did have some effect on the matrix protein gene expression profile. Their influence on native cells requires long-term evaluation.

Inter- and intraobserver variability in the postoperative evaluation of transpedicular stabilization: computed tomography versus magnetic resonance imaging - Corrected Proof

2010-02-22

Abstract: Background context: Computed tomography (CT) represents the state of the art for the postoperative verification of the implant position after transpedicular stabilizations. Magnetic resonance imaging (MRI) has not challenged the CT, yet, because of susceptibility artifacts but would be favorable as a diagnostic tool for its excellent soft-tissue qualities.Purpose: A study that analyzed if an artifact-reduced MRI could overcome this problem and provide sufficient data for the postoperative assessment was conducted.Study design: The study design was a radiologic comparison of CT and MRI techniques evaluating pedicle screw placement after spinal fusion.Patient sample: Fifty consecutive patients were given an MRI and a CT after a transpedicular stabilization surgery. Thirty-eight patients suffered from degenerative spinal disorders; three surgeries had become necessary because of spondylodiscitis, eight patients suffered from metastatic vertebrae destruction, and one patient experienced a fracture.Outcome measures: Any contact of a malpositioned pedicle screw with the dura and/or radicular structures was identified as an implant-associated complication and was compared with postoperative clinical patient findings.Methods: In total, 338 pedicular screws were analyzed in regard to their intrapedicular position. The double-blind evaluation of MRI and CT data was carried out by two radiologists and two spine surgeons. Accuracy of the CT analysis was calculated based on the interobserver agreement of 100%. Magnetic resonance imaging accuracy was calculated.Results: The interobserver accuracy of the CT data amounted to a median of 89.8% and in the MRI data of 86.7%. Intraobserver comparisons showed a significant difference between CT and magnetic resonance evaluations in one observer (κ=0.293). In all other observers, the results were concordant with kappa values from κ=0.328 to κ=0.702. There was a high degree of agreement regarding the diagnosis of malpositioned pedicle screw and corresponding clinical symptoms between both techniques.Conclusions: The presented data show that artifact-reduced MRI is equivalent to CT imaging in the postoperative evaluation of titanium spinal rod-screw systems. We therefore conclude that MRI should be considered as an alternative tool for the golden standard CT for postoperative imaging controls for its advantages in soft-tissue analysis.

Systematic review of the incidence of discitis after cervical discography - Corrected Proof

Shruti Gupta Kapoor, Jeremy Huff, Steven P. Cohen — 2010-02-22

Abstract: Background Context: Cervical discography is not uniformly used in part because of the fear of discitis. Studies report widely varying rates of this life-threatening infection.Purpose: The aim of this study was to estimate the incidence of discitis after cervical discography, delineate the consequences of discitis, and identify factors that may influence this complication.Study Design: Meta-analysis.Methods: Studies pertaining to cervical discography were identified by a literature review and bibliographic search. These were screened for inclusion into the meta-analysis by two reviewers. Data were collected on a wide range of clinical and demographic variables including age, gender, morbidities, number of patients, number of discograms, use of prophylactic antibiotics, type of surgical prep, number of needles used, and the number of patients and discs infected. Primary data were used to calculate the incidence of discitis per patient and per disc.Results: Fourteen studies were included in the analysis. Both procedural details and demographic information on patients were missing from eight studies. The mean age of patients ranged from 41 to 47 years, and gender distribution varied greatly. Antibiotics use was reported in three studies. Cervical discography was complicated by postprocedural discitis in 22 of 14,133 disc injections (0.15%) and 21 of 4,804 patients (0.44%). Only one patient suffered from an infection at more than one spinal level.Conclusions: The rate of discitis after cervical discography is relatively low. This can perhaps be further decreased by the use of prophylactic intradiscal antibiotics. Should the ability of cervical discography to improve surgical outcomes be proven, the fear of discitis should not preclude performance of disc provocation.

Assessment of spine surgery outcomes: inconsistency of change amongst outcome measurements - Corrected Proof

2010-02-22

Abstract: BACKGROUND CONTEXT: Outcomes of spinal treatments are evaluated by clinical relevance: the proportion of patients who reach a minimum clinically important outcome change. Outcomes are evaluated through multiple measurements, and the inconsistency of outcome change across measurements is not known.PURPOSE: The primary purpose of this study was to illustrate outcome inconsistencies after spinal surgery. Secondary goals of this study were to develop an index of overall change that incorporates outcome inconsistencies, to relate the index of overall change to patients' global assessment and satisfaction with treatment, to relate the index of global change to an intuitively understandable outcome: the level of tolerable pain.STUDY DESIGN: This study is a review of prospectively collected patient-reported outcomes data.PATIENT SAMPLE: Four hundred sixty patients from a large multicenter database were chosen. Those patients were included in the sample because they had undergone lumbar surgery and had baseline and 1-year follow-up scores. Baseline and 1-year follow-up scores for Oswestry Disability Index (ODI), physical component summary (PCS) of the Medical Outcome Study Short Form-36 (SF-36), numerical back and leg pain scales, and 1-year scores for satisfaction with results were included in the study.OUTCOME MEASURES: The outcome measures of the study were preoperative and 1-year postoperative scores for ODI, PCS, back pain scale, leg pain scale, health transition item of the SF-36, and satisfaction with results scales.METHODS: Oswestry Disability Index, SF-36, and pain scales were administered before and 1 year after spinal surgery. Satisfaction with results questionnaires were administered 1 year after surgery. The following threshold values were previously established and were used to evaluate outcome changes: minimum clinically important difference (MCID), substantial clinical benefit (SCB), and standard error of the mean. The following proportions of patients were determined according to outcome changes: “deteriorated,” “no change,” “below MCID,” “above MCID,” and “above SCB.” The consistency of outcome change was determined amongst the four outcome measures. An index of overall change was developed and related to patients' answers to the health transition item of the SF-36 and to the satisfaction with results scale. The overall change index was also compared with the tolerable pain level.RESULTS: Only 40.5% of patients report consistent outcome changes on all four measures. The overall change index was significantly correlated to the global change and satisfaction scale (ρ=.67, p less than .001). The overall change index was clearly associated with the tolerable pain level.CONCLUSIONS: Efforts should be made to take into account the inconsistency of outcomes and to make clinical relevance more readily understandable by patients and clinicians.

Biomimetic calcium phosphate coatings as bone morphogenetic protein delivery systems in spinal fusion - Corrected Proof

2010-01-25

Abstract: Background Context: Use of recombinant human bone morphogenetic protein-2 (rhBMP-2) has been shown to enhance spinal fusion rates. Case reports of soft-tissue swelling, ectopic bone formation, and osteolysis have recently surfaced. It is hypothesized that incorporation of rhBMP-2 within a calcium phosphate (CaP) coating may help to localize delivery and mitigate these complications.Purpose: To compare the characteristics of posterolateral fusion between rabbits receiving rhBMP-2 delivered via physical adsorption to a collagen sponge or rhBMP-2 incorporated within the physical structure of a CaP coating on a collagen sponge.Study Design/Setting: New Zealand white rabbit model of posterolateral lumbar fusion at L5–L6.Methods: Eighteen (18) New Zealand white rabbits underwent posterolateral spinal fusion at L5–L6. Rabbits received bilateral collagen sponges that were either coated with CaP (n=3), coated with CaP and dipped in rhBMP-2 (n=3), coated with a hybrid CaP–rhBMP-2 film (n=6), or coated with a hybrid CaP-rhBMP-2 film and dipped in rhBMP-2 (n=6). Animals were followed weekly with radiographs and were sacrificed at 6 weeks. Fusion masses were further characterized by manual palpation, computed tomography, and histology.Results: Radiographic evaluation showed that animals in Group 3 (incorporated BMP) fused at 4 weeks, whereas animals in Group 2 (adsorbed BMP) and Group 4 (incorporated and adsorbed BMP) fused by 6 weeks. Animals that received rhBMP-2 physically adsorbed to the collagen sponge showed extension of the fusion mass beyond the L5–L6 level in 56% of cases and bone resorption in 78%. Histology of fusion masses showed mature bone formation in animals belonging to Groups 2, 3, and 4 and extensive osteoclast recruitment in animals belonging to Groups 2 and 4.Conclusions: Delivery of rhBMP-2 via incorporation within CaP coatings results in increased rates of radiographic fusion. The burst release profile of rhBMP-2 adsorbed to surfaces, although effective in achieving fusion, may result in increased osteoclast recruitment.

Surgical site infection after osteotomy of the adult spine: does type of osteotomy matter? - Corrected Proof

Albert F. Pull ter Gunne, C.J.H.M. van Laarhoven, David B. Cohen — 2010-01-18

Abstract: Objective: The objective of the study was to assess the incidence and identify significant risk factors for surgical site infection (SSI) after spinal osteotomy.Summary of Data: Surgical site infection after spinal surgery is frequently seen. It occurs between 0.7% and 12% of patients, leading to higher morbidity, mortality, and health-care costs. Osteotomy procedures are known to have increased blood losses and surgical times when compared with other spinal surgeries. Both of these factors have previously been identified as significant risk factors for SSI. We performed a cohort study of this high-risk population to identify risk factors and rates of SSI after spinal osteotomy surgery and identify difference in risk between different types of osteotomies.Study Design: Retrospective review of all adult patients who underwent spinal osteotomy surgery for deformity by an orthopedic surgeon in our university.Methods: All electronic records of adult orthopedic patients whom underwent a spinal osteotomy procedure at our department between January 1998 and December 2005 (n=363) were abstracted. During surgery, a pedicle subtraction osteotomy (transpedicular wedge resection), anterior spine osteotomy (resection of anterior and middle columns), posterior Smith-Petersen osteotomy (resection of a portion of the superior and inferior lamina, ligamentum flavum, and the inferior and superior articular processed), or a combined anterior and posterior osteotomy (vertebral column resection [VCR]) (circumferential resection of the vertebrae via either a combined anterior/posterior or posterior-only approach) was performed. Primary outcome measurement was SSI. Subanalysis to deep and superficial SSI was performed.Results: Twenty patients (5.5%) were found to have an SSI, with nine (2.5%) having deep SSI. Analysis showed that patients undergoing VCR (p=.042) had a significant increased risk for deep SSI (11.1%). Obese patients had a significant increased risk (p=.045) for superficial SSI.Conclusions: Vertebral column resection has a significant increased risk for SSI (11.1%) compared with other types of osteotomies (4.1%). When possible, osteotomy techniques that involve less extensive exposures and soft-tissue dissection should be chosen to minimize deep SSI risk. Obese patients should be counseled on weight loss to try minimizing superficial SSI risk.

SWISSspine—a nationwide health technology assessment registry for balloon kyphoplasty: methodology and first results - Corrected Proof

2009-10-12

Abstract: Background Context: The Swiss Federal Office of Public Health demanded a nationwide health technology assessment registry for cervical and lumbar total disc arthroplasty and for balloon kyphoplasty (BKP) to make a decision about reimbursement of these interventions.Purpose: The goal of the SWISSspine registry is to generate evidence about the safety and effectiveness of these technologies. We report on results of patients with balloon kyphoplasty.Study Design/Setting: Prospective, multicenter, observational case series.Patient Sample: From March 2005 until June 2008, 331 interventions with 391 treated levels in 320 patients have been documented. 75.6% of patients were females with mean age of 74 years (range 43–95.2 years); mean age of males was 72.6 years (range 41.4–93 years).Outcome Measures: Surgeon-administered outcome instruments were primary intervention form for BKP, implant, and follow-up form; patient self-reported measures were Euroqol-5D, North American Spine Society, and a comorbidity questionnaire.Methods: Data were recorded perioperative, at 3 months, 1 year, and annually thereafter. Wilcoxon signed-rank test was used for comparison of preoperative to postoperative measurements. Multivariate regression was used for identifying factors with a significant influence on the outcome.Results: Significant and clinically relevant reduction of back pain, improvement of quality of life (QoL), and reduction of pain killer consumption were seen in the 1-year follow-up. Improvement of preoperative segmental kyphosis was achieved in the majority of cases. There were three symptomatic cement extrusions with radiculopathy documented.Conclusions: Balloon kyphoplasty is a safe and effective treatment concerning pain reduction, QoL improvement, and pain killer consumption. The SWISSspine registry proved to be an excellent tool for evaluation of this new technology, and its results, in combination with an elaborate health technology assessment report, led to a permanent coverage of BKP by the basic health insurance.

REMOVED: In defense of King et al.: the validity of manual examination in assessing patients with neck pain - Corrected Proof

Nikolai Bogduk — 2008-11-10

This article has been removed consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.

Evaluation of five scoring systems for cervical spondylogenic myelopathy - Corrected Proof

Kristina Dalitz, Hans-Ekkehart Vitzthum — 2008-09-09

Abstract: Background context: Comparison of measured clinical deficits and outcomes is vital for international discussion about the identification and treatment of cervical spondylotic myelopathy (CSM). There is currently little information comparing outcomes as assessed by different CSM scoring systems.Purpose: To qualitatively and quantitatively analyze five specific CSM outcome scores that are frequently used to assess the grade of severity and outcome after operative decompression.Study design: This retrospective study evaluated the Nurick score, the Japanese Orthopedic Association score (JOA score), the Cooper myelopathy scale (CMS), the Prolo score, and the European myelopathy score (EMS).Patient sample: The study included 43 patients with clinical and morphological signs of CSM, who underwent ventral decompression. Data were evaluated in sufficient detail to objectively assess the scores.Outcome measures: Clinical findings (funicular and radicular symptoms), recovery rate, symptom duration, age, economic situation, time away from employment, somatic-evoked potentials, and radiological findings were assessed.Methods: Scores were assessed using both pre- and postoperative clinical data. Correlations between scores, score improvement, and how well the scores reflected the clinical, diagnostic, and anamnestic data were analyzed using nonparametric, descriptive statistical tests. The recovery rate, as a measure of cumulative outcome, was also assessed and compared for each scoring system.Results: All five scores were suitable for qualitatively assessing the clinical characteristics and progression of cervical myelopathy. All showed a statistically significant correlation (p<.05), and measured postoperative improvement (p<.001). All scores also reflected clinical deficits except for the Prolo score, which rates the severity of CSM with an emphasis on data related to the economic impact on the patient's situation rather than on clinical symptoms per se. Quantitative assessment of clinical symptom improvement varied greatly among the scores, for example, Nurick score (33%) versus JOA score (81%). The recovery rates, as a measure of cumulative improvement, showed less variation among most of the scores. The Nurick score and the EMS measured clinical deficit improvements in significantly fewer patients than did the JOA score (p<.05).Conclusions: Evaluating the recovery rate is essential for comparing the results of the five CSM scores evaluated in this study. There was a large quantitative difference among the scores as the result of the different criteria used to produce each score. Qualitatively, all five scores allowed evaluation of cervical myelopathy, but only the recovery rate allowed for statistical comparison. Advancements in the treatment of CSM depend on the ability of clinicians to evaluate the therapeutic results of CSM studies. This study suggests that using the recovery rate to assess outcome is best for comparing studies that use different scores.