Quality of in-hospital care in traumatic spinal column and cord injuries (TSC/SCI) in I.R Iran

PURPOSE

This study aimed to implement the Quality of Care (QoC) Assessment Tool from the National Spinal Cord/Column Injury Registry of Iran (NSCIR-IR) to map the current state of in-hospital QoC of individuals with Traumatic Spinal Column and Cord Injuries (TSCCI).

METHODS

The QoC Assessment Tool, developed from a scoping review of the literature, was implemented in NSCIR-IR. We collected the required data from two primary sources. Questions regarding health system structures and care processes were completed by the registrar nurse reviewing the hospital records. Questions regarding patient outcomes were gathered through patient interviews.

RESULTS

We registered 2812 patients with TSCCI over six years from eight referral hospitals in NSCIR-IR. The median length of stay in the general hospital and intensive care unit was four and five days, respectively. During hospitalization 4.2% of patients developed pressure ulcers, 83.5% of patients reported satisfactory pain control and none had symptomatic urinary tract infections. 100%, 80%, and 90% of SCI registration centers had 24/7 access to CT scans, MRI scans, and operating rooms, respectively. Only 18.8% of patients who needed surgery underwent a surgical operation in the first 24 h after admission. In-hospital mortality rate for patients with SCI was 19.3%.

CONCLUSION

Our study showed that the current in-hospital care of our patients with TSCCI is acceptable in terms of pain control, structure and length of stay and poor regarding in-hospital mortality rate and timeliness. We must continue to work on lowering rates of pressure sores, as well as delays in decompression surgery and fatalities.

The Diagnostic Process of Spinal Post-traumatic Deformity: An Expert Survey of 7 Cases, Consensus on Clinical Relevance Does Exist

STUDY DESIGN

Survey of cases.

OBJECTIVE

To evaluate the opinion of experts in the diagnostic process of clinically relevant Spinal Post-traumatic Deformity (SPTD).

SUMMARY OF BACKGROUND DATA

SPTD is a potential complication of spine trauma that can cause decreased function and quality of life impairment. The question of when SPTD becomes clinically relevant is yet to be resolved.

METHODS

The survey of 7 cases was sent to 31 experts. The case presentation was medical history, diagnostic assessment, evaluation of diagnostic assessment, diagnosis, and treatment options. Means, ranges, percentages of participants, and descriptive statistics were calculated.

RESULTS

Seventeen spinal surgeons reviewed the presented cases. The items' fracture type and complaints were rated by the participants as more important, but no agreement existed on the items of medical history. In patients with possible SPTD in the cervical spine (C) area, participants requested a conventional radiograph (CR) (76%-83%), a flexion/extension CR (61%-71%), a computed tomography (CT)-scan (76%-89%), and a magnetic resonance (MR)-scan (89%-94%). In thoracolumbar spine (ThL) cases, full spine CR (89%-100%), CT scan (72%-94%), and MR scan (65%-94%) were requested most often. There was a consensus on 5 out of 7 cases with clinically relevant SPTD (82%-100%). When consensus existed on the diagnosis of SPTD, there was a consensus on the case being compensated or decompensated and being symptomatic or asymptomatic.

CONCLUSIONS

There was strong agreement in 5 out of 7 cases on the presence of the diagnosis of clinically relevant SPTD. Among spine experts, there is a strong consensus to use CT scan and MR scan, a cervical CR for C-cases, and a full spine CR for ThL-cases. The lack of agreement on items of the medical history suggests that a Delphi study can help us reach a consensus on the essential items of clinically relevant SPTD.

LEVEL OF EVIDENCE

Level V.

Spinal Post-traumatic Deformity: An International Expert Survey Among AO Spine Knowledge Forum Members

STUDY DESIGN

Survey among spine experts.

OBJECTIVE

To investigate the different views and opinions of clinically relevant spinal post-traumatic deformity (SPTD).

SUMMARY OF BACKGROUND DATA

There is no clear definition of clinically relevant SPTD. This leads to a wide variation in characteristics used for diagnosis and treatment indications of SPTD. To understand the current concepts of SPTD a survey was conducted among spine trauma surgeons.

METHODS

Members of the AO Spine Knowledge Forum Trauma participated in an online survey. The survey was divided in 4 domains: Demographics, criteria to define SPTD, risk factors, and management. The data were collected anonymously and analyzed using descriptive statistics, absolute, and relative frequencies. Consensus on dichotomous outcomes was set to 80% of agreement.

RESULTS

Fifteen members with extensive experience in treatment of spinal trauma participated, representing the 5 AO Spine Regions. Back pain was the only criterion for definition of SPTD with complete agreement. Consensus (≥80%) was reached for kyphotic angulation outside normative ranges and impaired function. Eighty-seven percent and 100% agreed that a full-spine conventional radiograph was necessary in diagnosing and treating SPTD, respectively. The "missed B-type injury" was rated at most important by all but 1 participant. There was no agreement on other risk factors leading to clinically relevant SPTD. Concerning the management, all participants agreed that an asymptomatic patient should not undergo surgical treatment and that neurological deficit is an absolute surgical indication. For most of the participants the preferred surgical treatment of acute injury in all spine regions but the subaxial region is posterior fixation.

CONCLUSION

Some consensus exists among leading experts in the field of spine trauma care concerning the definition, diagnosis, risk factors, and management of SPTD. This study acts as the foundation for a Delphi study among the global spine community.

Complete Versus Incomplete Surgical Resection in Intramedullary Astrocytoma: Systematic Review with Individual Patient Data Meta-Analysis

STUDY DESIGN

Systematic reviewBackground: Considering the infiltrative nature of intramedullary astrocytoma, the goal of surgery is to have a better patient related outcome.

OBJECTIVE

To compare the overall survival (OS) and neurologic outcomes of complete vs incomplete surgical resection for patients with intramedullary astrocytoma.

METHODS

A comprehensive search of MEDLINE, CENTRAL and EMBASE was conducted by two independent reviewers. Individual patient data (IPD) analysis and multivariate Cox Proportional Hazard Model was developed to measure the effect of surgical strategies on OS, post-operative neurological improvement (PNI), and neurological improvement in the last follow up (FNI).

RESULTS

We included 1079 patients from 35 studies. Individual patient data of 228 patients (13 articles) was incorporated into the integrative IPD analysis. Kaplan-Meier survival analysis showed complete resection (CR) significantly improved OS in comparison with the incomplete resection (IR) (log-rank test, P = .004). In the multivariate IPD analysis, three prognostic factors had significant effect on the OS: (1) Extent of Resection, (2) pathology grade, and (3) adjuvant therapy. We observed an upward trend in the popularity of chemotherapy, but CR, IR, and radiotherapy had relatively stable trends during three decades.

CONCLUSION

Our study shows that CR can improve OS when compared to IR. Patients with spinal cord astrocytoma undergoing CR had similar PNI and FNI compared to IR. Therefore, CR should be the primary goal of surgery, but intraoperative decisions on the extent of resection should be relied on to prevent neurologic adverse events. Due to significant effect of adjuvant therapy on OS, PNI and FNI, it could be considered as the routine treatment strategy for spinal cord astrocytoma.

Does Interbody Cage Lordosis and Position Affect Radiographic Outcomes After Single-level Transforaminal Lumbar Interbody Fusion?

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

The objective of this study was to determine if the degree of interbody cage lordosis and cage positioning are associated with changes in postoperative sagittal alignment after single-level transforaminal lumbar interbody fusion (TLIF).

SUMMARY OF BACKGROUND DATA

Ideal sagittal alignment and lumbopelvic alignment have been shown to correlate with postoperative clinical outcomes. TLIF is one technique that may improve these parameters, but whether the amount of cage lordosis improves either segmental or lumbar lordosis (LL) is unknown.

METHODS

A retrospective review was performed on patients who underwent single-level TLIF with either a 5-degree or a 12-degree lordotic cage. LL, segmental lordosis (SL), disk height, center point ratio, cage position, and cage subsidence were evaluated. Correlation between center point ratio and change in lordosis was assessed using the Spearman correlation coefficient. Secondary analysis included multiple linear regression to determine independent predictors of change in SL.

RESULTS

A total of 126 patients were included in the final analysis, with 51 patients receiving a 5-degree cage and 75 patients receiving a 12-degree cage. There were no differences in the postoperative minus preoperative LL (∆LL) (12-degree cage: -1.66 degrees vs. 5-degree cage: -2.88 degrees, P =0.528) or ∆SL (12-degree cage: -0.79 degrees vs. 5-degree cage: -1.68 degrees, P =0.513) at 1-month follow-up. Furthermore, no differences were found in ∆LL (12-degree cage: 2.40 degrees vs. 5-degree cage: 1.00 degrees, P =0.497) or ∆SL (12-degree cage: 1.24 degrees vs. 5-degree cage: 0.35 degrees, P =0.541) at final follow-up. Regression analysis failed to show demographic factors, cage positioning, or cage lordosis to be independent predictors of change in SL. No difference in subsidence was found between groups (12-degree cage: 25.5% vs. 5-degree cage: 32%, P =0.431).

CONCLUSION

Lordotic cage angle and cage positioning were not associated with perioperative changes in LL, SL, or cage subsidence after single-level TLIF.

LEVEL OF EVIDENCE

Level III.

Patient Factors Impacting Baseline Motor Evoked Potentials (MEPs) in Patients Undergoing Cervical Spine Surgery for Myelopathy or Radiculopathy

STUDY DESIGN

Retrospective review of 2532 adults who underwent elective surgery for cervical radiculopathy or myelopathy with intraoperative neuromonitoring (IONM) with motor evoked potentials (MEPs) between 2017 and 2019.

OBJECTIVE

Evaluate attainability of monitorable MEPs across demographic, health history, and patient-reported outcomes measure (PROM) factors.

SUMMARY OF BACKGROUND DATA

When baseline IONM responses cannot be obtained, the value of IONM on mitigating the risk of postoperative deficits is marginalized and a clinical decision to proceed must be made based, in part, on the differential diagnosis of the unmonitorable MEPs. Despite known associations with baseline MEPs and anesthetic regimen or preoperative motor strength, little is known regarding associations with other patient factors.

METHODS

Demographics, health history, and PROM data were collected preoperatively. MEP baseline responses were reported as monitorable or unmonitorable at incision. Multivariable logistic regression estimated the odds of having at least one unmonitorable MEP from demographic and health history factors.

RESULTS

Age [odds ratio (OR)=1.031, P <0.001], sex (male OR=1.572, P =0.007), a primary diagnosis of myelopathy (OR=1.493, P =0.021), peripheral vascular disease (OR=2.830, P =0.009), type II diabetes (OR=1.658, P =0.005), and hypertension (OR=1.406, P =0.040) were each associated with increased odds of unmonitorable MEPs from one or more muscles; a history of thyroid disorder was inversely related (OR=0.583, P =0.027). P atients with unmonitorable MEPs reported less neck-associated disability and pain ( P <0.036), but worse SF-12 physical health and lower extremity (LE) and upper extremity function ( P <0.016). Compared with radiculopathy, unmonitorable MEPs in myelopathy patients more often involved LE muscles. Cord function was monitorable in 99.1% of myelopathic patients with no reported LE dysfunction and no history of hypertension or diabetes.

CONCLUSION

Myelopathy, hypertension, peripheral vascular disease, diabetes, and/or symptomatic LE dysfunction increased the odds of having unmonitorable baseline MEPs. Unmonitorable baseline MEPs was uncommon in patients without significant LE weakness, even in the presence of myelopathy.

The Role of Family-wise Error Rate in Determining Statistical Significance

The threshold for statistical significance is determined by the maximum allowable probability of Type I error (α). For studies that test multiple hypotheses or make multiple comparisons, the probability of at least 1 Type I error (family-wise error rate; FWER) increases as the number of hypotheses/comparisons increase. It is generally best practice to set the acceptable threshold for FWER to be less than or equal to α. Bonferroni correction and Tukey honestly significant difference test are 2 of the more common methods to control for FWER. When doing exploratory analysis or evaluating secondary outcomes of a study, it may not be necessary or desirable to control for FWER, which reduces the power of the study. However, deciding to control for FWER should be decided during the design of the study.

Growth Factor Gene-Modified Cells in Spinal Cord Injury Recovery; a Systematic Review

BACKGROUND

Numerous pre-clinical studies have been performed in recent years on the effects of growth factor gene-modified cells' administration in spinal cord injury (SCI). However, findings of these studies are contradictory.

OBJECTIVE

The present study aims to conduct a systematic review and meta-analysis on animal studies evaluating the effects of growth factor gene-modified cells' administration on locomotion recovery following SCI.

METHODS

A search of the Medline, Embase, Scopus and Web of Science databases was conducted, including all animal studies until the end of 2020. Two researchers screened search results, summarized relevant studies and assessed risk of bias, independently.

RESULTS

Thirty-three studies were included in the final analysis. Transplantation of growth factor gene-modified cells in the injured spinal cord resulted in a significant improvement in animals' locomotion compared with non-treated animals [standardized mean difference (SMD)=1.86; 95% CI: 1.39-2.33; p<0.0001)] and non-genetically modified cells treated animals (SMD=1.30; 0.80-1.79; p<0.0001). Transplantation efficacy of these cells failed to achieve significance in moderate lesions (p=0.091), when using modified neural stem/progenitor cells (p=0.164), when using synthetic neurotrophins (p=0.086) and when the number of transplanted cells was less than 1.0 × 10⁵ cells per animal (p = 0.119).

CONCLUSION

The result showed that transplantation of growth factor gene-modified cells significantly improved locomotion in SCI animal models. However, there is a major concern regarding the safety of genetically modified cells' transplantation, in terms of overexpressing growth factors. Further studies are needed before any effort to perform a translational and clinical study.

Indicators of Quality of Care in Individuals With Traumatic Spinal Cord Injury: A Scoping Review

STUDY DESIGN

Scoping review.

OBJECTIVES

To identify a practical and reproducible approach to organize Quality of Care Indicators (QoCI) in individuals with traumatic spinal cord injury (TSCI).

METHODS

A comprehensive literature review was conducted in the Cochrane Central Register of Controlled Trials (CENTRAL) (Date: May 2018), MEDLINE (1946 to May 2018), and EMBASE (1974 to May 2018). Two independent reviewers screened 6092 records and included 262 full texts, among which 60 studies were included for qualitative analysis. We included studies, with no language restriction, containing at least 1 quality of care indicator for individuals with traumatic spinal cord injury. Each potential indicator was evaluated in an online, focused group discussion to define its categorization (healthcare system structure, medical process, and individuals with Traumatic Spinal Cord Injury related outcomes), definition, survey options, and scale.

RESULTS

A total of 87 indicators were identified from 60 studies screened using our eligibility criteria. We defined each indicator. Out of 87 indicators, 37 appraised the healthcare system structure, 30 evaluated medical processes, and 20 included individuals with TSCI related outcomes. The healthcare system structure included the impact of the cost of hospitalization and rehabilitation, as well as staff and patient perception of treatment. The medical processes included targeting physical activities for improvement of health-related outcomes and complications. Changes in motor score, functional independence, and readmission rates were reported as individuals with TSCI-related outcomes indicators.

CONCLUSION

Indicators of quality of care in the management of individuals with TSCI are important for health policy strategists to standardize healthcare assessment, for clinicians to improve care, and for data collection efforts including registries.

Power Analysis for Null Hypothesis Significance Testing

Before conducting a scientific study, a power analysis is performed to determine the sample size required to test an effect within allowable probabilities of Type I error (α) or Type II error (β). The power of a study is related to Type II error by 1-β. Most scientific studies set α=0.05 and power=0.80 as minimums. More conservative study designs will decrease α or increase power, which will require a larger sample size. The third and final parameter required for a power analysis is the effect size (ES). ES is a measure of the strength of the observation in the outcome of interest (ie, the dependent variable). ES must be estimated from pilot studies or published values. A small ES will require a larger sample size than a large ES. It is possible to detect statistically significant findings even for very small ES, if the sample size is sufficiently large. Therefore, it is also essential to evaluate whether ES is sufficiently large to be clinically meaningful.

A Comparison of Revision Rates and Patient-Reported Outcomes for a 2-Level Posterolateral Fusion Augmented With Single Versus 2-Level Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Retrospective, single institution, multisurgeon case control series.

OBJECTIVE

To determine whether there are differences in reoperation rates or outcomes for patients undergoing 2-level posterolateral fusion (PLF) augmented by a transforaminal lumbar interbody fusion (TLIF) at only one of the levels or at both.

METHODS

A total of 416 patients were identified who underwent 2-level PLF with a TLIF at either one of those levels (n = 183) or at both (n = 233) with greater than 1-year follow-up. Demographic, surgical, radiographic, and clinical data was reviewed for each patient. These included age, sex, race, body mass index, smoking status, Charleston Comorbidity Index, operative time, estimated blood loss, length of stay, and patient-reported outcome measures.

RESULTS

Each cohort underwent 24 reoperations. Although the number of overall reoperations was not significantly different (P > .05), among the reoperation types, there were significantly more reoperations for adjacent segment disease in the 2-level group compared to the 1-level group (19 vs 12, P = .04). There was no difference in reoperation for pseudarthrosis between the groups (P > .05). Although both groups experienced significant improvements in Oswestry Disability Index (P < .001) and Short Form-12 health questionnaire (P < .001), there were no differences between improvements for 1- versus 2-level cohorts.

CONCLUSIONS

For patients undergoing 2-level PLF in the setting of a TLIF, using a TLIF at one versus both levels does not seem to influence reoperation rates or outcomes. However, reoperation rates for adjacent segment disease are increased in the setting of a 2-level PLF augmented by a 2-level TLIF.

The case for surgery of the injured spine in the management of traumatic cord injuries

Spinal cord injury can be a life-altering trauma for patients and can be costly to patients and society alike. Generally recognized as biphasic, these injuries have both primary and secondary drivers. Although the primary insult is largely unavoidable, prevention of secondary injury mechanisms-and the resultant cascade-has been a target of substantial research. Continued spinal cord compression has been recognized as one of several deleterious secondary mechanisms, and decompressive and stabilization surgery has been routinely used for neuroprotection in this setting. Numerous biomechanical and animal studies have confirmed its potential utility. More recently, several high-quality randomized trials have concluded that early surgery for spinal cord injury improves rates of recovery when compared with delayed or nonoperative management. Herein, we argue that early surgery for spinal cord injury with continued cord compression offers significant benefit and should be undertaken when not contraindicated.

Surgical Decision Making for Thoracolumbar Spine Injuries in Polytrauma Patients

The management of thoracolumbar spine injuries in patients with multiple traumatic injuries is a challenge complicated by multiple competing medical and surgical demands. Safe and effective treatment of polytrauma patients with a thoracolumbar spine injury requires a multidisciplinary approach that involves surgical and critical care teams. The Thoracolumbar Injury Classification and Severity Score, which was developed to facilitate consistent surgical decision making in patients with a thoracolumbar spine injury, provides objective criteria for the classification and management of thoracolumbar spine injuries. The AOSpine study group recently developed a comprehensive thoracolumbar injury classification system that was subsequently used to create the Thoracolumbar AOSpine Injury Score, which helps guide thoracolumbar spine injury management via objective criteria. These scoring systems have been effectively used in clinical practice and allow for a focused and objective assessment of thoracolumbar spine injuries. Both the Thoracolumbar Injury Classification and Severity Score and the Thoracolumbar AOSpine Injury Score should be routinely used in treatment decision making to optimize outcomes and avoid unnecessary surgical treatment in polytrauma patients with a thoracolumbar spine injury.

[The AOSpine Classification of Thoraco-Lumbar Spine Injuries]

Optimal treatment of injuries to the thoracolumbar spine is based on a detailed analysis of instability, as indicated by injury morphology and neurological status, together with significant modifying factors. A classification system helps to structure this analysis and should also provide guidance for treatment. Existing classification systems, such as the Magerl classification, are complex and do not include the neurological status, while the TLICS system has been accused of over-simplifying the influence of fracture morphology and instability. The AOSpine classification group has developed a new classification system, based mainly upon the Magerl and TLICS classifications, and with the aim of overcoming these drawbacks. This differentiates three main types of injury: Type A lesions are compression lesions to the anterior column; Type B lesions are distraction lesions of either the anterior or the posterior column; Type C lesions are translationally unstable lesions. Type A and B lesions are split into subgroups. The neurological damage is graded in 5 steps, ranging from a transient neurological deficit to complete spinal cord injury. Additional modifiers describe disorders which affect treatment strategy, such as osteoporosis or ankylosing diseases. Evaluations of intra- and inter-observer reliability have been very promising and encourage the introduction of this AOSpine classification of thoracolumbar injuries to the German speaking community.

Can anatomic level of injury on MRI predict neurological level in acute cervical spinal cord injury?

BACKGROUND

Determining neurological level of injury (NLI) is of paramount importance after spinal cord injury (SCI), although its accuracy depends upon the reliability of the neurologic examination. Here, we determine if anatomic location of cervical cord injury by MRI (MRI level of injury) can predict NLI in the acute traumatic setting.

METHODS

A retrospective review was undertaken of SCI patients with macroscopic evidence of cervical cord injury from non-penetrating trauma, all of whom had undergone cervical spine MRI and complete neurologic testing. The recorded MRI information included cord lesion type (intra-axial edema, hemorrhage) and MRI locations of upper and lower lesion boundary, as well as lesion epicenter. Pearson correlation and Bland-Altman analyses were used to assess the relationship between MRI levels of injury and NLI.

RESULTS

All five MRI parameters, namely (1) upper and (2) lower boundaries of cord edema, (3) lesion epicenter, and (4) upper and (5) lower boundaries of cord hemorrhage demonstrated statistically significant, positive correlations with NLI. The MRI locations of upper and lower boundary of hemorrhage were found to have the strongest correlation with NLI (r = 0.72 and 0.61, respectively; p < 0.01). A weaker (low to moderate) correlation existed between lower boundary of cord edema and NLI (r = 0.30; p < 0.01). Upper boundary of cord hemorrhage on MRI demonstrated the best agreement with NLI (mean difference 0.03 ± 0.73; p < 0.01) by Bland-Altman analysis.

CONCLUSIONS

MRI level of injury has the potential to serve as a surrogate for NLI in instances where the neurologic examination is either unavailable or unreliable.

Survey of French spine surgeons reveals significant variability in spine trauma practices in 2013

BACKGROUND

In France, attempts to define common ground during spine surgery meetings have revealed significant variability in clinical practices across different schools of surgery and the two specialities involved in spine surgery, namely, neurosurgery and orthopaedic surgery.

OBJECTIVES

To objectively characterise this variability by performing a survey based on a fictitious spine trauma case. Our working hypothesis was that significant variability existed in trauma practices and that this variability was related to a lack of strong scientific evidence in spine trauma care.

METHODS

We performed a cross-sectional survey based on a clinical vignette describing a 31-year-old male with an L1 burst fracture and neurologic symptoms (numbness). Surgeons received the vignette and a 14-item questionnaire on the management of this patient. For each question, surgeons had to choose among five possible answers. Differences in answers across surgeons were assessed using the Index of Qualitative Variability (IQV), in which 0 indicates no variability and 1 maximal variability. Surgeons also received a questionnaire about their demographics and surgical experience.

RESULTS

Of 405 invited spine surgeons, 200 responded to the survey. Five questions had an IQV greater than 0.9, seven an IQV between 0.5 and 0.9, and two an IQV lower than 0.5. Variability was greatest about the need for MRI (IQV=0.93), degree of urgency (IQV=0.93), need for fusion (IQV=0.92), need for post-operative bracing (IQV=0.91), and routine removal of instrumentation (IQV=0.94). Variability was lowest for questions about the need for surgery (IQV=0.42) and use of the posterior approach (IQV=0.36). Answers were influenced by surgeon specialty, age, experience level, and type of centre.

CONCLUSION

Clinical practice regarding spine trauma varies widely in France. Little published evidence is available on which to base recommendations that would diminish this variability.

Factors associated with the development of pressure ulcers after spinal cord injury

STUDY DESIGN

Cross-sectional observational study.

OBJECTIVES

To examine variables associated with the development of pressure ulcers in subjects with spinal cord injury (SCI).

SETTING

SCI patients under coverage of the State Welfare Organization of Iran.

METHODS

Mobile rehabilitation teams gathered data from 20 of the 30 provinces in Iran. There were 8104 SCI patients registered in the database; 7489 patients were included in the analysis. The prevalence of PU in patients aged <10 years was lower than those aged >10; therefore, we used different logistic models for these groups. Likewise, separate models were created for patients who had experienced SCI during the past year versus patients injured >1 year before the evaluation.

RESULTS

PU was present in 34.6% of the patients. The variables associated with PU in patients aged <10 years were female gender and the time passed since SCI. In patients aged >11 years, male gender, the time passed since SCI, lower level of education, lack of an intimate partner, quadriplegia and older age presented a significant association with PU. Patients for whom <1 year has passed since SCI, male gender, quadriplegia and older age were associated with PU. And patients for whom >1 year had passed since SCI, male gender, quadriplegia, older age, lower level of education and lack of an intimate partner were associated with PU.

CONCLUSION

SCI patients are a heterogeneous group and the risk factors associated with PU may vary in specific subgroups. Different models are needed to describe PU in SCI patients depending on the patient's age and the time passed since SCI.

An evidence-based mobile decision support system for subaxial cervical spine injury treatment

Bringing evidence to practice is a key issue in modern medicine. The key barrier to information searching is time. Clinical decision support systems (CDSS) can improve guideline adherence. Mounting evidence exists that mobile CDSS on handheld computers support physicians in delivering appropriate care to their patients. Subaxial cervical spine injuries account for almost half of spine injuries, and a majority of spinal cord injuries. A valid and reliable classification exists, including evidence-based treatment algorithms. A mobile CDSS on this topic was not yet available. We developed and tested an iPhone application based on the Subaxial Injury Classification (SLIC) and 5 evidence-based treatment algorithms for the surgical approach to subaxial cervical spine injuries. The application can be downloaded for free. Users are cordially invited to provide feedback in order to direct further development and evaluation of CDSS for traumatic lesions of the spinal column.

Thromboprophylaxis in patients with acute spinal injuries: an evidence-based analysis

BACKGROUND

The increased risk for venous thromboembolic events following spinal trauma is well established. The purpose of the present study was to examine the literature in order to determine the optimum thromboprophylaxis regimen for patients with acute spinal injuries with or without spinal cord injury.

METHODS

EMBASE, MEDLINE, and Cochrane databases were searched from the earliest available date to April 2008 for clinical trials comparing different methods of thromboprophylaxis in adult patients following acute spinal injuries (with or without spinal cord injury). Outcome measures included the prevalences of deep-vein thrombosis and pulmonary embolism and treatment-related adverse events.

RESULTS

The search yielded 489 studies, but only twenty-one of them fulfilled the inclusion criteria. The prevalence of deep-vein thrombosis was significantly lower in patients without spinal cord injury as compared with patients with spinal cord injury (odds ratio = 6.0; 95% confidence interval = 2.9 to 12.7). Patients with an acute spinal cord injury who were receiving oral anticoagulants had significantly fewer episodes of pulmonary embolism (odds ratio = 0.1; 95% confidence interval = 0.01 to 0.63) than those who were not receiving oral anticoagulants (either untreated controls or patients managed with low-molecular-weight heparin). The start of thromboprophylaxis within the first two weeks after the injury resulted in significantly fewer deep-vein-thrombosis events than delayed initiation did (odds ratio = 0.2; 95% confidence interval = 0.1 to 0.4). With regard to heparin-based pharmacoprophylaxis in patients with spinal trauma, low-molecular-weight heparin significantly reduced the rates of deep-vein thrombosis and bleeding episodes in comparison with the findings in patients who received unfractionated heparin, with odds ratios of 2.6 (95% confidence interval = 1.2 to 5.6) and 7.5 (95% confidence interval = 1.0 to 58.4) for deep-vein thrombosis and bleeding, respectively.

CONCLUSIONS

The prevalence of deep-vein thrombosis following a spine injury is higher among patients who have a spinal cord injury than among those who do not have a spinal cord injury. Therefore, thromboprophylaxis in these patients should start as early as possible once it is deemed safe in terms of potential bleeding complications. Within this population, low-molecular-weight heparin is more effective for the prevention of deep-vein thrombosis, with fewer bleeding complications, than unfractionated heparin is. The use of vitamin K antagonists appeared to be effective for the prevention of pulmonary embolism.

Surgeon equipoise as an inclusion criterion for the evaluation of nonoperative versus operative treatment of thoracolumbar spinal injuries

BACKGROUND CONTEXT

Prospective studies have failed to demonstrate the superiority of either operative or nonoperative treatment of thoracolumbar fractures. Similar to other surgical fields, research has been limited by the variability in surgical interventions, difficult recruitment, infrequent pathology, and the urgency of interventions.

PURPOSE

To outline factors precluding randomized controlled trials in spinal fractures research, and describe a novel methodology that seeks to improve on the design of observational studies.

STUDY DESIGN/SETTING

A preliminary report describing an observational study design with clinical equipoise as an inclusion criterion. The proposed methodology is a cohort study with head-to-head comparison of operative and nonoperative treatment regimens in an expertise-based trial fashion. Patients are selected retrospectively by an expert panel and clinical outcomes are assessed to compare competing treatment regimens. Surgeon equipoise served as an inclusion criterion.

PATIENT SAMPLE

Patients with closed or open thoracolumbar spinal fracture with or without neurological impairment, presenting to one of two different trauma centers between 1991 and 2005 (N = 760).

OUTCOME MEASURES

Homogeneity of baseline clinical and demographic data and distribution of prognostic risk factors between the operative and the nonoperative cohort.

METHODS

Patients treated for spine fractures at two University hospitals practicing opposing methods of fracture intervention were identified by medical diagnosis code searches (n = 760). A panel of spine treatment experts, blinded to the treatment received clinically has assessed each case retrospectively. Patients were included in the study when there was disagreement on the preferred treatment, that is, operative or nonoperative treatment of the injury. Baseline and initial data of a study evaluating nonoperative versus operative spinal fracture treatment are presented.

RESULTS

One hundred and ninety patients were included in the study accounting for a panel discordance rate of 29%. The distribution of baseline characteristics and demographics of the study populations were equal across the parallel cohorts enrolled in the study, that is, no differences in prognostic factors were observed.

CONCLUSIONS

The use of clinical equipoise as an inclusion criterion in comparative studies may be used to avoid selection bias. Using multivariate analysis of retrospectively assembled parallel cohorts, a valid comparison of operative and nonoperative spine fracture treatment strategies and their outcomes is possible.

Exophytic intramedullary meningioma of the cervical spinal cord

Intramedullary spinal cord neoplasms are relatively uncommon. The most common intramedullary tumors are astrocytomas and ependymomas. Meningiomas can occur as an intradural tumor; however, they are typically in the extramedullary compartment. A 42-year-old male presented with progressive sensory loss in the upper extremities and lower extremity weakness. Pre-operative imaging suggested an intramedullary cervical lesion. To treat the progressive neurological abnormality, surgical resection was planned. At surgery, it was noted that the tumor originated in the cervical spinal cord and extended into the extramedullary region. Histology confirmed the lesion to be a meningioma. This meningioma variant has not previously been described. Spinal meningiomas may occur in locations other than intradural, extramedullary locations, and should be included in the differential diagnosis of intramedullary lesions. Intramedullary meningiomas can be successfully treated with surgery.

Spinal injuries after falls from hunting tree stands

BACKGROUND CONTEXT

Spinal injuries are common sequelae of falls from hunting tree stands. Significant neurological injury is not uncommon and can result in significant morbidity as well as enormous expenditure of health care dollars. Recent literature on the subject is limited.

PURPOSE

The purpose of this study was to identify precipitating causes, characterize the spectrum of spinal injury, and determine potential interventional safety and prevention recommendations.

STUDY DESIGN

A retrospective study.

METHODS

Medical record review of 22 patients admitted either directly or via referral to a level I spinal cord injury referral center over a 10-year period (1995-2005) after a fall from a hunting tree stand.

RESULTS

All patients were men with a mean age of 46 years (range, 27-80 years). Initial acute care hospitalization averaged 10 days (range, 2-28 days). The average height of fall was 18 feet (range, 10-30 feet). Four of 19 falls (21%) occurred during the morning hours, 2 of 19 falls occurred during the afternoon, and 13 of 19 falls (68%) occurred during the evening hours. Time lapse from injury to presentation to an emergency department ranged from 30 minutes to 14 hours. Alcohol use was a factor in 2 of 20 falls (10%). Hypothermia complicated 3 of 21 cases (14%). Associated injuries were present in 12 of 21 patients (57%) and included fractures to the axial and appendicular skeleton, pneumothoraces, a retroperitoneal bleed, and a brachial plexopathy. Eight of 22 patients (37%) sustained injury to the cervical spine. Five of these 8 patients (63%) had neurological deficits (3 complete and 2 incomplete spinal cord injuries). Thirteen of 22 (59%) patients sustained injury to the thoracic or lumbar spine. Ten of these 13 (77%) had neurologic deficits (3 complete and 7 incomplete). Nine of 22 (41%) patients were treated nonoperatively; the remaining 13 (59%) underwent operative intervention.

CONCLUSIONS

Falls from hunting tree stands remain a significant cause of spinal injury and subsequent disability. The best intervention for these injuries is prevention. There is a continued need for hunter safety education to reduce the incidence of these injuries with emphasis on safety harness usage, proper installation and annual inspection of tree stands, hunting in groups with periodic contact, the use of communication devices, and abstinence from alcohol consumption while hunting.

A new classification and guide for surgical treatment of spinal tuberculosis

So far, there is no widely accepted classification system based on objective findings that can serve as a guide in selecting the treatment method for spinal tuberculosis. This retrospective study evaluates patients with spinal tuberculosis (Pott's disease) treated with different surgical procedures. Our aim was to outline a new classification of spinal tuberculosis. A retrospective review of 76 cases (55 male and 25 female patients) of spinal tuberculosis was conducted. Five of the patients were treated medically, and the others who were treated surgically were classified into three types (I, II and III) according to the new classification system for spinal tuberculosis. All 76 patients were classifiable by this new system. The most common complication observed was local kyphosis (maximum 8 degrees) in type-II patients, but none of the patients needed correction. No neurological deterioration was observed in any of the cases. This new classification system helps in differentiating the various manifestations of spinal tuberculosis and appears to correlate with the surgical treatment of spinal tuberculosis. We believe that this new classification system can be used as a practical guide in the treatment of Pott's disease.

Posterior longitudinal ligament status in cervical spine bilateral facet dislocations

OBJECTIVE

It is generally accepted that cervical spine bilateral facet dislocation results in complete disruption of the posterior longitudinal ligament. The goal of this study was to evaluate the integrity of numerous spine-stabilizing structures by MRI, and to determine if any associations between injury patterns exist with respect to the posterior longitudinal ligament status.

DESIGN

Retrospective case series.

PATIENTS

A retrospective review was performed of 30 cervical spine injury subjects with bilateral facet dislocation. Assessment of 1.5T MRI images was carried out for: intervertebral disc disruption, facet fracture, and ligamentous disruption. Statistical analyses were performed to evaluate for associations between various injury patterns and posterior longitudinal ligament status.

RESULTS

The frequency of MRI abnormalities was: anterior longitudinal ligament disruption (26.7%), disc herniation or disruption (90%), posterior longitudinal ligament disruption (40%), facet fracture (63.3%) and disruption of the posterior column ligament complex (97%). There were no significant associations between injury to the posterior longitudinal ligament and other structures. Compared to surgical reports, MRI was accurate for determining the status for 24 of 26 ligaments (three of three anterior longitudinal ligament, seven of nine posterior longitudinal ligament, and 14 of 14 posterior column ligament complex) but generated false negatives in two instances (in both MRI showed an intact posterior longitudinal ligament that was torn at surgery).

CONCLUSIONS

In contradistinction to the existing concept, the posterior longitudinal ligament can remain intact in a substantial proportion of hyperflexion injuries that produce bilateral cervical facet dislocation. Posterior longitudinal ligament integrity is not associated with any other injury pattern related to the anterior longitudinal ligament, intervertebral disc or facet fracture.

Posterior thoracic segmental pedicle screw instrumentation: evolving methods of safe and effective placement

The use of pedicle screw instrumentation in the spine has evolved over the last two decades. The initial use of pedicle screws began in the lumbar spine. As surgeons have become more comfortable with the complex anatomy required for accurate screw placement, the use of pedicle instrumentation has evolved to include their use in the thoracolumbar and thoracic spine. The impetus behind their increased use is a result of the many advantages that pedicle screw anchorage offers over traditional hook and rod constructs. Improved deformity correction and overall construct rigidity are two important advantages of pedicle screw instrumentation due its three-column control over the spinal elements. First, pedicle screw instrumentation obviates the need to place instrumentation within the spinal canal with its inherent risk of neurologic injury. Second, the placement of pedicle screws is independent of facet or laminar integrity and thus has been extremely useful in traumatic, neoplastic, and degenerative conditions. The benefits of pedicle screws in the thoracic spine has been tempered by the potential for catastrophic neurological or soft tissue injuries due to the close proximity of these structures. The narrow and inconsistent shape of the thoracic pedicles, especially in spinal deformity, makes their placement technically challenging. As a result, surgeons have employed a number of techniques to ensure the safe and efficacious placement of thoracic pedicle screws. Detailed anatomic landmarks used to determine pedicle location, intraoperative imaging including navigation, and neurophysiological monitoring are some of the techniques currently used by surgeons. The implementation of these techniques and a thorough understanding of the complex three-dimensional anatomy have allowed surgeons to successfully place thoracic and thoracolumbar pedicle screws.

Post-traumatic spinal deformity

There are approximately 50,000 fractures to the bony spinal column each year in the United States. The vast majority of unstable spinal injuries are recognized early and managed appropriately. Rarely, the initial treatment may have been inadequate, or in less obvious injuries, less aggressive immobilization techniques may have been chosen. This along with continued exposure to physiologic stresses may lead to a gradual post-traumatic deformity that may further impede the functional as well as emotional status of these often already compromised patients. The management of post-traumatic deformity can be extremely challenging. A post-traumatic kyphotic deformity may occur in the cervical, thoracic, thoracolumbar, or lumbar spine, and once appropriate imaging studies are obtained, careful surgical considerations must be undertaken. Surgical intervention is considered if the kyphotic deformity is progressive over time or there is new onset or progression of a neurologic deficit. Surgical procedures include either a posterior or anterior only approach or any variation of a combined anterior or posterior procedure. In most cases a posterior only fusion is often insufficient for optimal correction and stabilization. Although the majority of patients developing a post-traumatic deformity usually occur after spinal column trauma initially treated nonoperatively, several miscellaneous causes of post-traumatic deformity may occur after surgery. These include nonunion, implant failure, Charcot spine, and technical error. The overall outcome after the surgical management of post-traumatic deformity has been satisfactory with better outcomes in the patients treated earlier as opposed to later. Operative complications include the increased risk of neurologic injury because of the draping of the neural elements over the anterior vertebral elements, any pre-existing spinal cord injury, and possible scarring with cord tethering. Trauma to the spinal cord and column is a devastating injury that may be fraught with many complications including post-traumatic deformity. Certainly, the best treatment is prevention with close follow-up and early intervention when needed. Once present, the treatment of post-traumatic deformity follows basic biomechanical principles consisting of re-establishing the integrity of the compromised spinal columns so that spinal stability can be restored.

Three-dimensional cartilage formation by bone marrow-derived cells seeded in polylactide/alginate amalgam

Bone marrow-derived cells are considered as candidate cells for cartilage tissue engineering by virtue of their ability to undergo chondrogenesis in vitro when cultured in high density or when embedded within a three-dimensional matrix in the presence of growth factors. This study evaluated the potential of human bone marrow-derived cells for cartilage tissue engineering by examining their chondrogenic properties within a three-dimensional amalgam scaffold consisting of the biodegradable polymer, poly-L-lactic acid (PLA) alone, and with the polysaccharide gel, alginate. Cells were suspended either in alginate or medium and loaded into porous PLA blocks. Alginate was used to improve cell loading and retention within the construct, whereas the PLA polymeric scaffold provided appropriate mechanical support and stability to the composite culture. Cells seeded in the PLA/alginate amalgams and the plain PLA constructs were treated with different concentrations of recombinant human transforming growth factor-beta1 (TGF-beta 1) either continuously (10 ng/mL) or only for the initial 3 days of culture (50 ng/mL). Chondrogenesis was assessed at weekly intervals with cultures maintained for up to 3 weeks. Histological and immunohistochemical analysis of the TGF-beta 1-treated PLA/alginate amalgam and PLA constructs showed development of a cartilaginous phenotype from day 7 to day 21 as demonstrated by colocalization of Alcian blue staining with collagen type II and cartilage proteoglycan link protein. Expression of cartilage specific genes, including collagen types II and IX, and aggrecan, was detected in TGF-beta 1-treated cultures by reverse transcription-polymerase chain reaction analysis. The initiation and progression of chondrogenic differentiation within the polymeric macrostructure occurred with both continuous and the initial 3-day TGF-beta 1 treatment regimens, suggesting that key regulatory events of chondrogenesis take place during the early period of cell growth and proliferation. Scanning electron microscopy revealed abundant cells with a rounded morphology in the PLA/alginate amalgam. These findings suggest that the three-dimensional PLA/alginate amalgam is a potential candidate bioactive scaffold for cartilage tissue engineering applications.

Magnetic resonance imaging analysis of soft tissue disruption after flexion-distraction injuries of the subaxial cervical spine

STUDY DESIGN

A retrospective study was performed with the use of magnetic resonance imaging to evaluate the type and degree of soft tissue disruption associated with flexion-distraction injuries of the subaxial spine.

OBJECTIVE

To determine what soft tissue structures are injured in flexion-distraction injuries of the subaxial spine.

SUMMARY OF BACKGROUND DATA

Prior published reports of unilateral and bilateral cervical facet dislocations have described the analyzed mechanisms and biomechanics of this injury subtype. No retrospective magnetic resonance imaging analysis of associated soft tissue disruption has been documented.

METHODS

Magnetic resonance imaging evaluations of the cervical spine were obtained for all patients with a flexion-distraction injury, Stages 2 (unilateral facet dislocation) and 3 (bilateral facet dislocation), between September 1994 and May 1998. Two neuroradiologists, blinded to both clinical and radiographic findings, graded all the soft tissue structures for evidence of attenuation or disruption. The soft tissue structures were graded on a scale of 1 (intact), 2 (indeterminate), or 3 (disrupted).

RESULTS

For this study, 48 patients satisfied the inclusion criteria: 25 with unilateral facet dislocation and 23 with bilateral facet dislocation. Disruption to the posterior musculature, interspinous ligament, supraspinous ligament, facet capsule, ligamentum flavum, and posterior and anterior longitudinal ligaments was found in a statistically significant number of patients with bilateral facet dislocation. For most of these structures, disruption was found to be statistically significant in patients with a unilateral facet dislocation, except for the posterior longitudinal ligament, in which significance was not consistently demonstrated using 95% confidence intervals in the binomial testing. In a comparison between unilateral and bilateral facet dislocations using a two-sided Fisher's exact test, it was found that disruption to the anterior and posterior longitudinal ligaments and the left facet capsule were statistically significant, with all three more prominent in bilateral facet dislocation. A multivariate analysis between unilateral and bilateral facet dislocations showed that disruption to the anterior longitudinal ligament was associated significantly with a bilateral facet dislocation. Disc disruption was found to be associated significantly with both injury types, but was more common in bilateral facet dislocation, although this difference in intergroup comparisons was not statistically significant.

CONCLUSIONS

Unilateral and bilateral facet dislocations of the subaxial spine are associated with damage to numerous soft tissue structures that provide stability to the lower cervical spine. Damage to the posterior longitudinal ligament did not occur consistently in unilateral facet dislocations. Bilateral facet dislocations were associated significantly with disruption to the posterior and anterior longitudinal ligaments and left facet capsule, as compared with unilateral facet dislocations. Magnetic resonance imaging allows visualization of these disruptions.

In vitro genesis of subaxial cervical unilateral facet dislocations through sequential soft tissue ablation

STUDY DESIGN

In vitro anatomic study investigating the degree of soft tissue disruption required to produce a subaxial cervical unilateral facet dislocation.

OBJECTIVES

To develop an understanding of the relative contributions to stability of the subaxial cervical soft tissues and to define an anatomic threshold of injury necessary to produce a unilateral cervical facet dislocation.

SUMMARY OF BACKGROUND DATA

The literature at this time is unclear regarding the precise pathomechanics of a cervical unilateral facet dislocation and the required threshold of soft tissue injury necessary for its genesis. Published clinical reports do not make any specific reference to these factors or are unclear in their objectivity.

METHODS

Two adjacent vertebra at a time in 10 fresh-frozen subaxial cervical spine specimens (C2-C3 to C6-C7) were transfixed in the coronal plane with 3.5-mm Schanz screws. A steady unilateral vertical distraction force resulting in lateral cervical flexion was applied to these screws as the surrounding cervical soft tissue structures were sequentially ablated. Four experimental models were developed, varying the order of soft tissue disruption.

RESULTS

The physiologic coupling of subaxial cervical unilateral distraction and rotation, because of the spatial orientation or inclination of the cervical facet joints, allowed the creation of a unilateral facet dislocation without an additional flexion moment. Disruption of the ipsilateral articular capsule, ligamentum flavum, and more than half of the anulus fibrosus was necessary for the genesis of a unilateral facet dislocation. Disruption of the supraspinous and interspinous ligaments was not necessary but appeared to facilitate or lessen the force required to dislocate a unilateral facet. Disruption of the anterior and posterior longitudinal ligaments and intertransverse ligaments was not necessary to create a unilateral facet dislocation.

CONCLUSION

This anatomic study further supports the theory that discontinuity of the anterior and posterior longitudinal ligaments is not necessary for a unilateral facet dislocation to occur. The ipsilateral facet capsule, anulus fibrosus, and ligamentum flavum appear to be the physical soft tissue restraints that need to be disrupted to produce a unilateral facet dislocation.

Distraction extension injuries of the cervical spine

Twenty-four consecutive patients with cervical distraction extension injuries were retrospectively reviewed to study the safety and efficacy of various treatment protocols in this type of cervical spine injury. Sixteen of 24 patients with cervical distraction extension injuries underwent surgical stabilization. All patients undergoing surgical stabilization were noted to have a stable fusion at their latest follow-up. There were three instances of surgically related neurologic deterioration as a result of over-distraction of the anterior column interspace at the time of graft placement. The overall mortality rate was 42% in this aged patient population. Anterior reconstruction of the cervical spine with an anterior cervical graft and plate acting as a tension band is the ideal treatment method for stabilization of acute distraction extension injuries involving primarily the soft tissue structures (anterior longitudinal ligament and intervertebral disc). Type 2 injuries, depending on the degree of displacement and the adequacy of closed reduction, may need to be approached initially posteriorly to obtain adequate alignment, followed by an anterior reconstructive procedure. Great care should be taken during anterior graft placement to avoid over-distraction of the spine. If nonsurgical intervention is selected, close regular radiographic follow-up is necessary to detect early vertebral malalignment, which may predispose to spinal cord dysfunction. Older patients sustaining this injury have a high mortality rate.

Fenestration of the extracranial vertebral artery: review of the literature

STUDY DESIGN

A case report on fenestration of the extracranial vertebral artery found at forensic autopsy.

OBJECTIVE

To describe an extracranial vertebral artery fenestration involving the subaxial cervical region, assessed radiographically and angiographically at forensic autopsy, in a young man.

SUMMARY OF BACKGROUND DATA

Duplications or fenestrations of the extracranial course of the vertebral artery are rare and seen almost exclusively as a coincidental finding in angiographic studies. The terms "fenestration" and "duplication" are often incorrectly used synonymously. The former describes the passage of the duplicated vessel within the vertebral foramen transversarium, whereas the latter refers to the duplicated vessel coursing additionally through the spinal canal. The reported cases describing duplication are more common. Only three cases of vertebral extracranial fenestrations, involving only the upper cervical spinal segments, have been described in the literature.

RESULTS

Angiography showed a fenestration of the vertebral artery localized between the intervertebral spaces of C2-C3 and C3-C4. At dissection, the vertebral artery appeared as a single vessel in the area of the fenestration. Histologically, a distinct difference in the thickness and composition of the vessel walls was found between the two vessel trunks. At autopsy, no further anomalies were observed in the vessels supplying the brain, which is contrary to the commonly held belief that fenestration is frequently associated with vascular malformations.

CONCLUSION

Fenestration of the extracranial course of the vertebral artery is a developmental or congenital anomaly. A review of the literature demonstrated that this is apparently only a coincidental finding and has no pathologic significance.

The cause of neurologic deterioration after acute cervical spinal cord injury

STUDY DESIGN

A retrospective review was performed to identify patients at risk for secondary neurologic deterioration after complete cervical spinal cord injury.

OBJECTIVE

To examine the causes of early neurologic deterioration in patients with complete spinal cord injury at a regional spinal cord injury center.

SUMMARY OF BACKGROUND DATA

After complete spinal cord injury, neurologic deterioration occurs in a subgroup of patients. Despite anecdotal reports, no study has clearly identified the subgroups at highest risks.

METHODS

One hundred eighty-two patients with complete spinal cord injury were identified among 1904 consecutive patients with acute spinal trauma evaluated from March 1993 through September 1999. Parameters analyzed included demographics, mechanism of injury, American Spinal Cord Injury Association (ASIA) level on admission and during hospital stay, onset of ascension, blood pressure, hemoglobin, febrile episode, heparin administration, and the timing of operation and traction. Radiographs of patients with ascending complete spinal cord injury were reviewed with attention to fracture type and neurologic and vascular injuries.

RESULTS

Twelve of 186 patients with ASIA Grade A (6.0%) complete spinal cord injury had neurologic deterioration during the first 30 days after injury. No patients with penetrating injuries had deterioration. A significant association between death and ascension was observed. The onset of ascension of the injury could be categorized into three discrete temporal subsets. Early deterioration (less than 24 hours) was typically related to traction and immobilization. Delayed deterioration (between 24 hours and 7 days) was associated with sustained hypotension in patients with fracture dislocations. Late deterioration (more than 7 days) was observed in a patient with vertebral artery injuries.

CONCLUSION

Delayed neurologic deterioration in complete spinal cord injury (ASIA A) is not rare. Specific causes were identified among discrete temporal subgroups. Management of complete spinal cord injury can be improved with recognition of these temporal patterns and earlier intervention.

The significance of thoracolumbar spinal canal size in spinal cord injury patients

STUDY DESIGN

A prospective, consecutive case series.

OBJECTIVES

To determine the relation between spinal canal dimensions and Injury Severity Score and their association with neurologic sequelae after thoracolumbar junction burst fracture.

SUMMARY OF BACKGROUND DATA

There is a relation in the cervical spine between spinal canal dimension and its association with neurologic sequelae after trauma. A similar relation at the thoracolumbar junction has not been conclusively established.

METHODS

Forty-three patients with thoracolumbar junction burst fractures (T12-L2),13 with and 30 without neurologic deficit, were included. Computed tomographic scans were used to measure the sagittal and transverse diameters and the surface area of the spinal canal at the level of injury, as well as one level above and one level below the fracture level. Injury severity score was calculated for both groups. Statistical analysis comparing those with a neurologic deficit to those without was performed by Student's t test.

RESULTS

The ratio of sagittal-to-transverse diameter at the level of injury was significantly smaller in patients with a neurologic deficit than in those without a neurologic deficit (P < 0.05). The mean transverse diameter at the level of injury was significantly larger in patients with neurologic deficit than in the neurologically intact patients (P < 0.05). The surface area of the canal at the level below the injury was significantly larger in the patients with a neurologic deficit than in those without a deficit (P < 0.05). Patients with a neurologic deficit had a statistically higher Injury Severity Score when admitted than those without a neurologic deficit (P < 0.0001), although the difference became insignificant after the neurologic component of the scoring system was eliminated.

CONCLUSION

There are no anatomic factors at the thoracolumbar junction that predispose to neurologic injury after burst fracture. The shape of the canal after injury, however, as determined by the sagittal-to-transverse diameter ratio, was predictive of neurologic deficit.

The risk of foraminal violation and nerve root impingement after anterior placement of lumbar interbody fusion cages

STUDY DESIGN

Three groups of six embalmed cadaver spines underwent placement of lumbar interbody fusion cages centered either at midline, 10% lateral of midline, or 20% lateral of midline. The spines were evaluated for evidence of neuroforamen violation or nerve root impingement.

OBJECTIVES

To determine the potential for foraminal violation or nerve root impingement after correct placement and lateral misplacement of lumbar interbody fusion cages.

SUMMARY OF BACKGROUND DATA

Radicular symptoms after anterior cage placement have raised some concern about the potential for inadvertent device-related foraminal violation not adequately appreciated by intraoperative fluoroscopy.

METHODS

Preoperative computed tomography scanning and plain radiography was used to measure endplate dimensions at L4-L5 and to template the appropriately sized interbody fusion cages. The cadaveric specimens were randomly divided into three groups of six (Groups I-III) and instrumented at L4-L5 either at midline (I) or 10% (II) or 20% (III) lateral of midline. Postoperative computed tomography and plain radiography was evaluated for evidence of neuroforamen violation, followed by dissection of the specimens.

RESULTS

Foraminal violation occurred in one of six spines in group II (10% off midline) and in three of six spines in group III (20% off midline). Two of the three cadavers in group III with foraminal violation also were noted to have nerve root abutment on computed tomography scans and spinal dissection.

CONCLUSIONS

Excessive lateral placement of lumbar interbody fusion cages may result in foraminal violation and possible nerve encroachment. The "safe zone" for centering the cages extends approximately 5 mm on either side of midline.

Internet resources for spine surgeons

To classify web sites on common spinal disorders as to their utility for the spine surgeon and patient. Five common spinal disorders were used to generate lists of relevant sites. These sites were categorized as to their relevance for patients and surgeons, their sponsoring organization, and their comprehensiveness. A total of 56,249 web sites were found using the five key words on five search engines. Using the "And" operator, a total of 227 web sites were generated. The majority of sites were patient oriented. Physician- or organization-sponsored sites were the most common. Ten sites were found to have comprehensive information for both patients and spine surgeons. Many web sites exist that discuss disorders of the spine. Currently there is not any one web site that contains comprehensive information for both the spine surgeon and patient.