Efficacy of surgical decompression in the setting of complete thoracic spinal cord injury

A Review of Strategies Associated with Surgical Decompression in Traumatic Spinal Cord Injury

Traumatic spinal cord injury (TSCI) is frequent. Timely diagnosis and treatment have reduced the mortality, but the long-term recovery of neurologic functions remains ominous. After TSCI, tissue bleeding, edema, and adhesions lead to an increase in the intraspinal pressure, further causing the pathophysiologic processes of ischemia and hypoxia and eventually accelerating the cascade of secondary spinal cord injury. Timely surgery with appropriate decompression strategies can reduce that secondary injury. However, disagreement about the safety and effectiveness of decompression surgery and the timing of surgery still exists. The level and severity of spinal cord injury do have an impact on the timing of surgery; therefore, TSCI subpopulations may benefit from early surgery. Early surgery perhaps has little effect on recovery from complete TSCI but might be of benefit in patients with incomplete injury. Early decompression should be considered in patients with incomplete cervical TSCI. Patient age should not be used as an exclusion criterion for early surgery. The best time point for early surgery is although influenced by the shortest duration to thoroughly examine the patient's condition and stabilize the patient's state. After the patient's condition is fully evaluated, we can perform the surgical modality of emergency myelotomy and decompression. Therefore, a number of conditions should be considered, such as standardized decompression methods, indications and operation timing to ensure the effectiveness and safety of early surgical intervention, and promotion of the functional recovery of residual nerve tissue.

Complete Traumatic Spinal Cord Injury: Current Insights Regarding Timing of Surgery and Level of Injury

STUDY DESIGN

A narrative literature review.

OBJECTIVES

To review the neurological recovery patterns in traumatic spinal cord injury (tSCI) patients with a complete lack of motor and sensory function below the level of injury (ie, ASIA A [American Spinal Injury Association scale]), as well as the impact of level of injury and timing of surgical intervention.

RESULTS

Spontaneous neurological recovery in patients with complete tSCI differs per level of injury: patients with cervical and thoracolumbar tSCI recover ≥1 ASIA grade in 17.3% to 34.0% 1 year after injury, compared with 10.7% to 18.6% in thoracic tSCI. Surgical decompression within 24 hours has a beneficial effect on neurological recovery in patients with complete cervical tSCI, whereas this effect is less clear for thoracic and thoracolumbar tSCI. A 1- or 2-grade improvement in the ASIA scale does not necessarily result in functional recovery.

CONCLUSION

In complete tSCI, the level of injury as well as surgical timing affect neurological recovery. There appears to be a beneficial effect of early surgical decompression in patients with complete cervical tSCI, more so than for thoracic and thoracolumbar tSCI. Frequently, the effect of surgical intervention is evaluated by an improvement in ASIA grade, but it is unclear whether this scale is sensitive enough to evaluate meaningful effectiveness of the intervention and desired outcome for patients with tSCI.

Neurological recovery following traumatic spinal cord injury: a systematic review and meta-analysis

OBJECTIVE

Predicting neurological recovery following traumatic spinal cord injury (TSCI) is a complex task considering the heterogeneous nature of injury and the inconsistency of individual studies. This study aims to summarize the current evidence on neurological recovery following TSCI by use of a meta-analytical approach, and to identify injury, treatment, and study variables with prognostic significance.

METHODS

A literature search in MEDLINE and EMBASE was performed, and studies reporting follow-up changes in American Spinal Injury Association (ASIA) Impairment Scale (AIS) or Frankel or ASIA motor score (AMS) scales were included in the meta-analysis. The proportion of patients with at least 1 grade of AIS/Frankel improvement, and point changes in AMS were calculated using random pooled effect analysis. The potential effect of severity, level and mechanism of injury, type of treatment, time and country of study, and follow-up duration were evaluated using meta-regression analysis.

RESULTS

A total of 114 studies were included, reporting AIS/Frankel changes in 19,913 patients and AMS changes in 6920 patients. Overall, the quality of evidence was poor. The AIS/Frankel conversion rate was 19.3% (95% CI 16.2-22.6) for patients with grade A, 73.8% (95% CI 69.0-78.4) for those with grade B, 87.3% (95% CI 77.9-94.8) for those with grade C, and 46.5% (95% CI 38.2-54.9) for those with grade D. Neurological recovery was significantly different between all grades of SCI severity in the following order: C > B > D > A. Level of injury was a significant predictor of recovery; recovery rates followed this pattern: lumbar > cervical and thoracolumbar > thoracic. Thoracic SCI and penetrating SCI were significantly more likely to result in complete injury. Penetrating TSCI had a significantly lower recovery rate compared to blunt injury (OR 0.76, 95% CI 0.62-0.92; p = 0.006). Recovery rate was positively correlated with longer follow-up duration (p = 0.001). Studies with follow-up durations of approximately 6 months or less reported significantly lower recovery rates for incomplete SCI compared to studies with long-term (3-5 years) follow-ups.

CONCLUSIONS

The authors' meta-analysis provides an overall quantitative description of neurological outcomes associated with TSCI. Moreover, they demonstrated how neurological recovery after TSCI is significantly dependent on injury factors (i.e., severity, level, and mechanism of injury), but is not associated with type of treatment or country of origin. Based on these results, a minimum follow-up of 12 months is recommended for TSCI studies that include patients with neurologically incomplete injury.

Effects of early surgical decompression on functional and histological outcomes after severe experimental thoracic spinal cord injury

OBJECTIVE

In acute traumatic brain injury, decompressive craniectomy is a common treatment that involves the removal of bone from the cranium to relieve intracranial pressure. The present study investigated whether neurological function following a severe spinal cord injury improves after utilizing either a durotomy to decompress the intradural space and/or a duraplasty to maintain proper flow of cerebrospinal fluid.

METHODS

Sixty-four adult female rats (n = 64) were randomly assigned to receive either a 3- or 5-level decompressive laminectomy (Groups A and B), laminectomy + durotomy (Groups C and D), or laminectomy + duraplasty with graft (Group E and F) at 24 hours following a severe thoracic contusion injury (200 kilodynes). Duraplasty involved the use of DuraSeal, a hydrogel dural sealant. Uninjured and injured control groups were included (Groups G, H). Hindlimb locomotor function was assessed by open field locomotor testing (BBB) and CatWalk gait analysis at 35 days postinjury. Bladder function was analyzed and bladder wall thickness was assessed histologically. At 35 days postinjury, mechanical and thermal allodynia were assessed by the Von Frey hair filament and hotplate paw withdrawal tests, respectively. Thereafter, the spinal cords were dissected, examined for gross anomalies at the injury site, and harvested for histological analyses to assess lesion volumes and white matter sparing. ANOVA was used for statistical analyses.

RESULTS

There was no significant improvement in motor function recovery in any treatment groups compared with injured controls. CatWalk gait analysis indicated a significant decrease in interlimb coordination in Groups B, C, and D (p < 0.05) and swing speed in Groups A, B, and D. Increased mechanical pain sensitivity was observed in Groups A, C, and F (p < 0.05). Rats in Group C also developed thermal pain hypersensitivity. Examination of spinal cords demonstrated increased lesion volumes in Groups C and F and increased white matter sparing in Group E (p < 0.05). The return of bladder automaticity was similar in all groups. Examination of the injury site during tissue harvest revealed that, in some instances, expansion of the hydrogel dural sealant caused compression of the spinal cord.

CONCLUSIONS

Surgical decompression provided no benefit in terms of neurological improvement in the setting of a severe thoracic spinal cord contusion injury in rats at 24 hours postinjury. Decompressive laminectomy and durotomy did not improve motor function recovery, and rats in both of these treatment modalities developed neuropathic pain. Performing a durotomy also led to increased lesion volumes. Placement of DuraSeal was shown to cause compression in some rats in the duraplasty treatment groups. Decompressive duraplasty of 3 levels does not affect functional outcomes after injury but did increase white matter sparing. Decompressive duraplasty of 5 levels led to neuropathic pain development and increased lesion volumes. Further comparison of dural repair techniques is necessary.

Early versus late surgical decompression for traumatic thoracic/thoracolumbar (T1-L1) spinal cord injured patients. Primary results of a randomized controlled trial at one year follow-up

OBJECTIVE

To assess the efficacy of surgical decompression <24 (early) versus 24-72 hours (late) in thoracic/thoracolumbar traumatic spinal cord injury (TSCI).

METHODS

A randomized controlled trial (RCT) of 35 T1-L1 TSCI patients including early (n=16) and late (n=19) surgical decompression was conducted in the neurosurgery department of Shahid Rajaee Hospital from September 2010. Pre- and postoperative American Spinal Injury Association (ASIA) Impairment Scale (AIS), ASIA motor/sensory scores, length of hospitalization, complications, postoperative vertebral height restoration/rebuilding and angle reduction, and 12-month loss of height restoration/rebuilding and angle reduction were evaluated.

RESULTS

Sixteen patients (46%) had complete TSCI. No AIS change was seen in 17 (52%) patients. Complete TSCI patients had no motor improvement. The AIS change in this group was solely due to increased sensory scores. For incomplete TSCI, the mean motor score improved from 77 (± 22) to 92 (± 12) in early, and from 68 (± 22) to 82 (± 16) in late surgery. One deep vein thrombosis was observed in each group. There were 2 wound infections, one CSF leak, one case of meningitis, and one decubitus ulcer in the late surgery group. Six screw revisions were required.

CONCLUSION

Our primary results show overall AIS and motor score improvement in both groups. Motor improvement was only observed in incomplete TSCI. Two-grade improvements in AIS were seen in 3 early, and one late surgery patient.

Impact of multiple injuries on functional and neurological outcomes of patients with spinal cord injury

BACKGROUND

The effects of multiple injuries on the neurological and functional outcomes of patients with traumatic spinal cord injury (SCI) are debated-some groups have shown that subjects with multiple injuries have the same neurological and functional outcomes of those without them, whereas others have found that SCI patients with associated traumatic brain injury have worse functional status at admission and discharge and longer rehabilitation stays than patients without brain injury. Thus, the aim of this study was to compare the outcomes of SCI subjects with or without multiple injuries.

METHODS

A total of 245 patients with a traumatic SCI during the first rehabilitation stay after the development of the lesion (202 males and 43 females; age 39.8 ± 17 years; lesion to admission time 51.1 ± 58 days) were examined on a referral basis. Patients were assessed using the following measures: American Spinal Injury Association standards, Barthel Index, Rivermead Mobility Index, and Walking Index for Spinal Cord Injury. The statistical analysis comprised Poisson regression models with relative risks and 95% confidence intervals, adjusted for the following confounders: age, sex, lesion level, and ASIA impairment scale (AIS) grade. Student's T test was used to compare the outcomes of patients divided by AIS impairment and lesion level.

RESULTS

SCI patients with and without multiple injuries differed significantly with regard to the level and completeness of the lesion. Overall, patients with multiple injuries had worse functional status at admission and discharge than monotraumatic subjects. However, when adjusted for neurological features, the populations had comparable functional and neurological status at admission and discharge and similar rates of complications and discharge destinations. The separate analysis per each level of lesion/AIS grade showed that in some groups, patients with multiple injuries had a significant longer length of stay or worse functional status at rehabilitation admission (but not at discharge) than their monotraumatic counterparts.

CONCLUSIONS

Multiple injuries do not affect the neurological or rehabilitative prognosis of spinal cord injuries. At discharge, patients with spinal cord injuries with and without multiple injuries achieved similar results with regard to neurological and functional improvement. Some groups of patients with multiple injuries had a longer length of stay.

What do we currently know about thoracic spinal cord injury recovery and outcomes? A systematic review

OBJECT

The purpose of this paper was to systematically review and critically appraise the evidence for whether there are differences in outcomes or recovery after thoracic spinal cord injuries (SCIs) based on the spinal level, the timing of intervention, or cause of SCI.

METHODS

Systematic searches were conducted using PubMed/MEDLINE through January 5, 2012. From 486 articles identified, 10 included data on the population of interest. Included studies were assigned a level of evidence (LOE) rating based on study quality, and an overall strength of evidence was assessed. To estimate the effect of injury level on patient outcomes, the relative risk and risk difference were calculated when data were available.

RESULTS

From 486 citations identified, 3 registry studies and 7 retrospective cohort studies met the inclusion criteria. All were rated as being of poor quality (LOE III). Limited literature exists on the epidemiology of traumatic and nontraumatic SCI. Few studies evaluated outcomes based on SCI level within the thoracic spine. Pulmonary complications and thromboembolic events were less common in persons with lower thoracic SCI (T7-12) than in those with higher thoracic SCI (T1-6) in 2 large studies, but no differences were found in functional outcomes in 4 smaller studies. Patients undergoing earlier surgery (< 72 hours) may have fewer ventilator, ICU, and hospital days than those undergoing later surgery. One small study of SCI during repair of aortic aneurysm compared with traumatic SCI reported similar outcomes for both groups. There are substantial deficiencies in the scientific literature on thoracic SCI in regard to assessment, outcomes ratings, and effectiveness of therapy.

CONCLUSIONS

The overall strength of evidence for all outcomes reported is low. Definitive conclusions should not be drawn regarding the prognosis for outcome and recovery after thoracic SCI. From a physiological standpoint, additional methodologically rigorous studies that take into consideration various levels of injury in more anatomically and physiologically relevant form are needed. Use of validated, comprehensive outcomes tools are important to improve our understanding of the impact of thoracic SCI and aid in examining factors in recovery from thoracic SCI.

Rodent Models and Behavioral Outcomes of Cervical Spinal Cord Injury

Rodent spinal cord injury (SCI) models have been developed to examine functional and physiological deficits after spinal cord injury with the hope that these models will elucidate information about human SCI. Models are needed to examine possible treatments and to understand histopathology after SCI; however, they should be considered carefully and chosen based on the goals of the study being performed. Contusion, compression, transection, and other models exist and have the potential to reveal important information about SCI that may be related to human SCI and the outcomes of treatment and timing of intervention.

Preventing motor vehicle crashes related spine injuries in children

BACKGROUND

Spinal cord injury (SCI) is a devastating event that results in permanent disability for injured children. Among all etiologies of SCI, motor vehicle crashes (MVCs) are the leading cause and account for 29% of all traumatic SCIs in children. We tried to evaluate types and mechanisms of MVC-related spinal column and spinal cord injuries, risk factors, safety issues and legislation.

DATA SOURCES

A literature review was performed using PubMed from 1966 to 12th April 2010 with the following key words: children OR pediatric, spine, injury OR trauma, restraint, seat belt, motor vehicle, road OR traffic, collision OR crash, safety. Cross referencing of discovered articles was also performed.

RESULTS

Risk factors for MVC-related SCI include single vehicle crashes, vehicle rollover, and ejection of the passenger from the vehicle. Any anatomic region of the spinal cord may be injured as a result of MVC and may vary according to the type of accident and restraint system usage. Increasing use of three-point seat belts, which are more protective than isolated lap seat belts, has decreased the incidence of MVC-related SCI. There is evidence that airbag use without seatbelt use is associated with an increased risk of cervical spine fractures with or without SCI. Vehicle designers need to give more attention to the prevention of vehicle rollover and to improve occupant protection when rollover occurs.

CONCLUSIONS

MVC is a common cause of SCI in children; therefore, paying attention to risk factors and modes of prevention is important. As MVC-related SCI can lead to permanent disability, prevention and education play an important role in decreasing childrens' morbidity and mortality. Making behavior, roads and vehicles safer can significantly reduce MVC-related SCI in children.

Neurological and functional recovery in multiple injured patients with paraplegia: outcome after 1 year

BACKGROUND

Injuries of thoracic vertebrae in multiple trauma patients are often accompanied by severe thoracic injuries and sensorimotor deficits. However, until now, it is not clear whether and how the severity of trauma influences the neurologic and functional outcome in paraplegic patients during the first year after the trauma. The aim of the study was to compare two cohorts of multiple injured paraplegic patients with and without conversion in the American Spinal Injury Association Impairment Scale (AIS) with regard to the severity of spinal trauma, the severity of thorax trauma, the type of fracture, and the functional outcome 1 year after the date of injury.

METHODS

Twenty-one traumatic paraplegic patients (neurologic level T1-T12) were included in the study based on a retrospective analysis of the Heidelberg European Multicenter Study about Spinal Cord Injury database (www.emsci.org) from 2002 to 2007. In all patients, the Polytraumaschluessel (PTS), the AO classification, the AIS, and the Spinal Cord Independence Measure were collected. Patients with no change in the AIS (group 1, n=14) were compared with patients with AIS changes (group 2, n=7), and t test and χ test were performed (p<0.05).

RESULTS

Differences in both groups concerning fracture classification were confirmed (p=0.046). A relation between neurologic improvement in the AIS and the severity of trauma (p=0.058) after 1 year was not found. The subitem PTST in the thoracic area showed statistical significance comparing the two groups (p=0.005). Both groups significantly improved functionally (Spinal Cord Independence Measure, p=0.035) during the first year but with no significant difference between the groups after 1 year.

CONCLUSIONS

Our data suggest that functional improvement is achieved independently from neurologic recovery. The combined assessment of the PTS, the AO classification, and the AIS in multiple-injured paraplegic patients can contribute to provide a better prognostication of the neurologic changes during rehabilitation and the outcome after 1 year than the AIS alone.

Neurologic improvement after thoracic, thoracolumbar, and lumbar spinal cord (conus medullaris) injuries

STUDY DESIGN

Retrospective.

OBJECTIVE

With approximately 10,000 new spinal cord injury (SCI) patients in the United States each year, predicting public health outcomes is an important public health concern. Combining all regions of the spine in SCI trials may be misleading if the lumbar and sacral regions (conus) have a neurologic improvement at different rates than the thoracic or thoracolumbar spinal cord.

SUMMARY OF BACKGROUND DATA

Over a 10-year period between January 1995 to 2005, 1746 consecutive spinal injured patients were seen, evaluated, and treated through a level 1 trauma referral center. A retrospective analysis was performed on 150 patients meeting the criteria of T4 to S5 injury, excluding gunshot wounds. One-year follow-up data were available on 95 of these patients.

METHODS

Contingency table analyses (chi-squared statistics) and multivariate logistic regression. Variables of interest included level of injury, initial American Spinal Injury Association (ASIA), age, race, and etiology.

RESULTS

A total of 92.9% of lumbar (conus) patients neurologically improved one ASIA level or more compared with 22.4% of thoracic or thoracolumbar spinal cord-injured patients. Only 7.7% of ASIA A patients showed neurologic improvement, compared with 95.2% of ASIA D patients; ASIA B patients demonstrated a 66.7% improvement rate, whereas ASIA C had a 84.6% improvement rate. When the two effects were considered jointly in a multivariate analysis, ASIA A and thoracic/thoracolumbar patients had only a 4.1% rate of improvement, compared with 96% for lumbar (conus) and incomplete patients (ASIA B-D) and 66.7% to 72.2% for the rest of the patients. All of these relationships were significant to P < 0.001 (chi-square test). There was no link to age or gender, and race and etiology were secondary to region and severity of injury.

CONCLUSION

Thoracic (T4-T9) SCIs have the least potential for neurologic improvement. Thoracolumbar (T10-T12) and lumbar (conus) spinal cord have a greater neurologic improvement rate, which might be related to a greater proportion of lower motor neurons. Thus, defining the exact region of injury and potential for neurologic improvement should be considered in future clinical trial design. Combining all anatomic regions of the spine in SCI trials may be misleading if different regions have neurologic improvement at different rates. Over a ten-year period, 95 complete thoracic/thoracolumbar SCI patients had only a 4.1% rate of neurologic improvement, compared with 96.0% for incomplete lumbar (conus) patients and 66.7% to 72.2% for all others.

Prevalence of spinal cord injury in Tehran, Iran

BACKGROUND/OBJECTIVE

To determine the prevalence of traumatic spinal cord injury (SCI) in Tehran, Iran.

METHODS

A population-based study was performed. In a random cluster sampling, 100 addresses were selected as the starting point of the survey for each cluster consisting of 25 households. To expand the geographic dimension of each cluster, the interviewers skipped 3 of 4 houses in gathering data for each study unit. Each person with traumatic SCI was evaluated initially by a nurse and then by a neurosurgeon by physical examination and spinal imaging at the hospital or at home.

RESULTS

Ninety-seven percent of all surveyed agreed to participate in the study (2425 households, or 9006 persons). Four cases of SCI were identified. The point prevalence of SCI was 4.4 [95% CI = 1.2-11.4] per 10,000 people. Over the 5-year period from january 2003 through January 2008, the reported incidence rate of SCI was 2.2 (95% CI = 0.27-8.00) per 10,000 people.

CONCLUSIONS

In this, the first published population-based study from Iran, the prevalence of traumatic SCI in Tehran ranged from 1.2 to 11.4 per 10,000 people. More research is required to determine the patterns and causes of SCI. Development of a nationwide SCI registry or surveillance system is fundamental to an understanding of the epidemiology, and hence the prevention, of this costly health problem.

The efficacy of surgical decompression before 24 hours versus 24 to 72 hours in patients with spinal cord injury from T1 to L1--with specific consideration on ethics: a randomized controlled trial

Background

There is no clear evidence that early decompression following spinal cord injury (SCI) improves neurologic outcome. Such information must be obtained from randomized controlled trials (RCTs). To date no large scale RCT has been performed evaluating the timing of surgical decompression in the setting of thoracolumbar spinal cord injury. A concern for many is the ethical dilemma that a delay in surgery may adversely effect neurologic recovery although this has never been conclusively proven. The purpose of this study is to compare the efficacy of early (before 24 hours) verse late (24–72 hours) surgical decompression in terms of neurological improvement in the setting of traumatic thoracolumbar spinal cord injury in a randomized format by independent, trained and blinded examiners.

Methods

In this prospective, randomized clinical trial, 328 selected spinal cord injury patients with traumatic thoracolumbar spinal cord injury are to be randomly assigned to: 1) early surgery (before 24 hours); or 2) late surgery (24–72 hours). A rapid response team and set up is prepared to assist the early treatment for the early decompressive group. Supportive care, i.e. pressure support, immobilization, will be provided on admission to the late decompression group. Patients will be followed for at least 12 months posttrauma.

Discussion

This study will hopefully assist in contributing to the question of the efficacy of the timing of surgery in traumatic thoracolumbar SCI.

Trial Registration

RCT registration number: ISRCTN61263382

Effect of decompression on complete spinal cord injury in rats

To examine whether spinal cord decompression improves functional recovery and decreases lesion volumes in paraplegic (not paraparetic) rats and, if so, at what postoperative time it is most efficacious. The spinal cords of 63 female rats were compressed at T9 with Yasargil clips. Rats were assigned randomly to five different treatment groups of 3 s, 1 hr, 6 hr, 3 weeks, and 10 weeks. Locomotor behavior scoring was based on the Basso, Beattie, Bresnahan (BBB) Locomotor Rating Scale (Ohio State University, Columbus, OH) motor scores. Comparing five groups, the mean BBB was statistically higher in the 3-s group (P < 0.05). Comparison of progressive changes in BBB in each group revealed statistically meaningful improvement in the 3-s group, too. Spared surface area of spinal cord was 81.5 +/- 4.9% in 3-s group and 10.8 +/- 1.4% in the delayed groups of decompression (P = 0.039). Rats undergoing immediate decompression showed significantly better functional recovery and smaller lesion volumes.