Decompression Surgery
Acute traumatic SCI is a unifying syndrome that represents a variety of underlying pathologies and structural abnormalities. Generally, one of the primary goals of surgical management is decompression of neural structures. Studies evaluating depression surgery for SCI are reviewed.
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Author Year Country |
Methods | Outcome |
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| Ojo et al. (2017)
Nigeria Pre-Post N=35 |
Population: Mean age: 38.6±13.3 yr; Gender: male=24, female=11, Level of injury: cervical=27, thoracic=7, lumbar=1; Severity of injury: Frankel A=17, B=8, C=2, D=2, E=6. Intervention: Individuals who presented with acute, traumatic SCI were assessed at baseline and six mo following surgical decompression and spinal stabilization to determine whether surgical intervention enhances rehabilitation of individuals with SCI. Outcome measures were assessed at baseline and six mo following surgery. Outcome measures: Frankel grade; Complications. Chronicity: All individuals who had SCI and cord decompression surgery within a two-yr period were included in this study. |
1. Frankel grade at six mo following surgical intervention showed improvement in nine (25.7%) individuals. 2. All individuals who presented as Frankel Grade C or Grade D improved to Grade E, while none of those who presented with Frankel Grade E deteriorated. 3. Common complications of spine decompression and fixation were surgical site infections (11.4%) and spine and chest infections (11.4%). |
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Rahimi-Movaghar et al. (2006) Iran Case Series N=24 |
Population: Mean age: 26.7 yr; Gender: males=21, females=3; Injury etiology: motor vehicle accident=14, fall=5, unknown=5; Level of injury: T12-L3; Level of severity: Frankel A=17, C=5, D=2. Intervention: Individuals with traumatic conus medullaris SCI who underwent surgical decompression were retrospectively analyzed. Median follow-up time was 32 mo. Outcome Measures: Frankel Grade. |
1. Of the 17 individuals with Frankel Grade A, seven improved to C, two improved to D, two improved to E, and six remained the same. 2. Of the five individuals with Frankel Grade C, four improved to D and one improved to E. 3. Of the two individuals with Frankel Grade D, both improved to E. |
| Beisse et al.
(2005) USA Pre-Post N=30 |
Population: Mean age: 39.4 yr; Gender: males=23, females=7; Injury etiology: fall=12, sports=10, motor vehicle accident=3, violence=2, tumor=1, infection=1, degeneration=1; Level of injury: T5=1, T6=1, T7=1, T9=1, T12=10, L1=11, L2=5; Level of severity: Frankel scale A=4, B=3, C=7, D=10, unclassified=6; Mean time since injury: 10.6 days. Intervention: Individuals with thoracolumbar canal compromise underwent endoscopic anterior spinal canal decompression, interbody reconstruction, and stabilization. Mean follow-up time was 42 mo. Outcome Measures: Frankel Scale, Complications. |
1. Complications occurred in 11 individuals (36.7%). 2. There was no deterioration of the neurological function in any individual. 3. Based on the Frankel scale, 25% of individuals with complete paraplegia and 65% of those with incomplete neurological deficit improved at least one level on neurological examination. |
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Hu et al. (1993) USA Case Series N=69 |
Population: Mean age: 30.0 yr; Gender: males=51, females=18; Level of injury: L1=36, L2=12, L3=11, L4=9, L5=3; Injury etiology: motor vehicle accident (n=36), fall (n=31), struck with object (n=2); Level of severity: incomplete. Intervention: Individuals who underwent decompression surgery following lumbar SCI injury were retrospectively analyzed by type of decompression. Outcomes were assessed at a mean follow-up time of 19 mo. Outcome Measures: American Spinal Injury Association (ASIA) Motor Score. |
1. Overall, the average initial ASIA score was 19.4; 20.1 for the anterior decompression, 20.1 for the posterior decompression, and 17.2 for the fusion. 2. Anterior decompression improved by an average of 9.9 points. 3. Posterior decompression improved by an average of 10.2 points. 4. Fusion individuals improved by an average of 4.2 points. 5. There was no significant difference between those treated with anterior and posterior decompression (p>0.05); there was a significantly greater improvement seen in anterior and posterior decompression compared to fusion treated individuals (p<0.05). |
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Levi et al. (1991) USA Case Control NInitial=103, NFinal=71 |
Population: Incomplete deficit (INC, n=50): Median age: 32.5 yr; Gender: males=40, females=10; Injury etiology: motor vehicle accident=28, diving=9, fall=10, other=3; Level of injury: C3=7, C4=7, C5=19, C6=12, C7=5; Mean time since injury: 10.6 days. Complete deficit (COM, n=53): Median age: 25.4 yr; Gender: male=45, female=8; Injury etiology: motor vehicle accident=27, diving=15, fall=5, other=6; Level of injury: C3=2, C4=4, C5=29, C6=13, C7=5; Mean time since injury: 5.1 days. Intervention: Individuals who underwent anterior decompression were retrospectively analyzed based on timing of surgery: INC early (<24 hr, n=10), COM early (n=35), INC late (>24 hr, n=40), and COM late (n=18). Outcome Measures: Motor Score, Functional Grade, Hospitalization, Respiratory Procedures, Mortality. |
1. INC early: 37.2% improved motor score at discharge; 50% improved functional grade at discharge; 20 days in acute hospitalization. 2. INC late: 45% improved motor score at discharge; 22.5% improved functional grade at discharge; 22 days in acute hospitalization; one individual died. 3. There was no significant difference between INC early and late groups in motor score, functional grade, or hospitalization (all p>0.05). 4. COM early: 3.9% improved motor score at discharge; 11.4% improved functional grade at discharge; 38.7 days in acute hospitalization; 6.0 respiratory care procedures. 5. COM late: 4.5% improved motor score at discharge; 5.6% improved functional grade at discharge; 45.2 days in acute hospitalization; 9.86 respiratory care procedures. 6. There was no significant difference between COM early and late groups in motor score or functional grade (all p>0.05); however, the early group had significantly less days of hospitalization and significantly less respiratory procedures (all p<0.05). |
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Benzel & Larson (1987) USA Case Series N=99 |
Population: Level of injury: C4-C7; Level of severity: Neurological Grading System (NGS) I=35, II=11, III=8, IV=6, V=3, VI=23, VII=13; Mean time since injury: NGS I=22.5 days, II=46.2 days, III/IV/V=51.7 days, VI/VII=17.4 days. Intervention: Individuals who underwent decompression surgery to restore normal nerve connections following cervical spine fractures were retrospectively analyzed for outcomes post-surgery. Outcome Measures: Complications, Neurological Grading System. |
1. Four individuals died; three had NGS I and significant pulmonary problems and the 4th was NGS II at 3 mo post-op. 2. Complications included pneumonia (n=7), deep vein thrombosis (n=3), respiratory failure (n=4), and sepsis (n=1). 3. All NGS I individuals remained Grade I following surgery. 1. Of the 11 NGS II individuals eight improved (III=3, IV=3, V=2) and three remained the same following surgery. 2. Of the eight NGS III individuals six improved (IV=1, V=4, VI=1) and two remained the same following surgery. 3. Of the six NGS IV individuals five improved (V=5) and one remained the same following surgery. 4. Of the three NGS V individuals all three improved (VI=3) following surgery. 5. Of the 23 NGS VI individuals 19 improved (VII=19) and four remained the same following surgery. 6. All 13 NGS VII individuals remained the same following surgery. |
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Kiwerski (1986) Poland Case Control N=1180 |
Population: Level of injury: C1-C3=74, C3-C5=421, C5-C7=685; Level of severity: Frankel A=506, B=171, C=212, D=291. Intervention: Individuals who underwent cervical decompression surgery (SG; n=548) or conservative treatment (CG; n=632) following cervical SCI injury were retrospectively analyzed. Outcome Measures: Frankel score, Mortality. |
1. There was an improvement in 49% of CG individuals and 66% of SG individuals. 2. Mortality was 30% in individuals with complete SCI injuries and 4.3% in incomplete SCI injuries. 3. CG group: in individuals who were admitted within 6 hr there was an improvement of 2-3 Frankel grades in 41% of individuals and decreases with a greater time to admission. 4. SG group: in individuals who were admitted within 6 hr there was an improvement of 2-3 Frankel grades in 59% of individuals and decreases with a greater time to admission. |
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Benzel & Larson (1986a) USA Case Series N=105 |
Population: Mean age: 31.3 yr; Level of injury: T3-L4; Level of severity: Neurological Grading System (NGS) I=34, II=10, III=10, IV=12, V=11, VI=21, VII=7; Mean time since injury: NGS I=48.3 days, II=44.5 days, III/IV/V=35.4 days, VI/VII=19.4 days. Intervention: Individuals who underwent anterior decompression following thoracic and lumbar spine fractures were retrospectively analyzed for outcomes post-surgery. Outcome Measures: Complications, Neurological Grading System. |
1. Complications included pneumonia (n=5), deep vein thrombosis (n=3), respiratory failure (n=2), renal failure (n=2) and superficial infection (n=1). 2. All NGS I individuals remained Grade I following surgery. 3. Of the 10 NGS II individuals four improved (III=2, IV=1, V=1) and six remained the same following surgery. 4. Of the 10 NGS III individuals nine improved (IV=2, V=6, VI=1) and one remained the same following surgery. 5. Of the 12 NGS IV individuals all 12 improved (V=6, VI=6) following surgery. 6. Of the 11 NGS V individuals 10 improved (VI=10) and one remained the same following surgery. 7. Of the 21 NGS VI individuals 17 improved (VII=17) and four remained the same following surgery. 8. All seven NGS VII individuals remained the same following surgery. |
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Benzel & Larson (1986b) USA Case Control N=35 |
Population: Level of injury: C4-C7. Intervention: Individuals with complete myelopathies secondary to cervical spinal fractures underwent spinal decompressions (anterior; n=23, posterior; n=2) or nerve root decompression (n=10). Outcome Measures: Recovery of nerve root function. |
1. For those individuals treated with spinal decompressions, 15 showed substantial recovery of nerve root function. 2. None of the individuals treated with nerve root decompression showed recovery of nerve root function. |
Discussion
Several early studies have reported the effect of surgical decompression in cervical SCI. Kiwerski (1986) reported a retrospective series of individuals treated from the late 1960s to the time of publication. Individuals treated surgically and conservatively both had what was then an acceptable neurological outcome, but with surgery individuals showing superior results, with 66% and 49% of individuals showing neurological improvement at follow-up, respectively. Benzel et al. (1987) examined a series of surgically treated individuals with cervical SCI from 1979 to 1986 and demonstrated the possibility of neurological improvement with surgery even in groups of motor-complete injuries; however, there was no non-surgical control group in this study.
With respect to thoracolumbar SCI, Benzel et al. (1986a) described a series of 105 operative cases predominantly treated with anterior-only decompression (a formerly preferred approach). Despite no significant neurological improvement in those individuals with motor complete injuries, individuals with motor incomplete injuries went on to experience only minimal permanent neurological deficit. In this series, surgical efficacy could not be assessed due to absence of a comparator group. Hu et al. (1993) published a retrospective comparison of anterior-vs-posterior decompression in thoracolumbar SCI, finding no difference between approaches in terms of neurological outcome. Ultimately it is difficult to pinpoint the appropriateness of these studies today due to the vast improvements in surgical instrumentation in the intervening decades. Some centres perform endoscopic decompression in the setting of thoracolumbar SCI, with the thought of avoiding the significant morbidity of a thoracolumbar approach, while also achieving decompression of the compressive abnormality culprit (often the vertebral body). Beisse et al. (2005) report such a series, collected prospectively, that demonstrated comparable neurological outcomes to open surgery. Limitations to this approach include the inability to correct significant deformity.
Direct injury to the conus medullaris can present in a variety of neurological syndromes, as upper motor neuron fibres coalesce here and synapse with all anterior horn cells for the caudal lumbar and sacral spine. As such, a mix of upper motor neuron and lower motor neuron deficits to motor, bowel and bladder occur, depending on the specific anatomy of the injury. With respect to decompression of traumatic conus injuries, Rahimi-Movaghar et al. (2006) assessed a retrospective case series of individuals who primarily had suffered lumbar burst injuries with associated conus injuries. In this group, approximately 40% of individuals experienced neurological improvement after surgery, and a large majority experiencing an improvement attributed to recovery of an adjacent nerve root. As there was no non-operative control group, comparative efficacy of surgery could not be studied. The authors reported no effect of surgical timing on neurological outcome.
In addition to cord injury, there can often be an associated nerve root injury at or adjacent to the level of spinal trauma. In an important retrospective analysis, Benzel et al. (1986b) described substantial rates of improved nerve root function at the level adjacent to, or directly above, the injured spinal cord with surgical decompression of the neural foramen at the time of primary surgery. In contrast, none of the individuals who did not receive neural foramen decompression demonstrated nerve root function improvement. This suggests the reasonableness of pursuing nerve root decompression during surgery for SCI, despite nerve root compression not being a surgical indication in itself.
With respect to environments with economic limitations, Ojo et al. (2017) reported outcomes among a group of surgically treated individuals with SCI in Nigeria. Of 35 individuals, nine demonstrated improved Frankel grade at 6 months, and the group had an overall acceptable complication profile. Although there was no comparator group, the authors propose decompression and stabilization surgery as a reasonable proposition to enhance functional outcome, despite the challenges of complex spinal instrumentation in their economic setting.
Conclusion
There is level 3 evidence (based on 1 case control: Kiwerski 1986) that cervical decompression results in improved neurological functioning in comparison to conservative treatment. This is supported by level 4 evidence (based on 1 case series: Benzel & Larson, 1987) showing neurological improvement but without a control group.
There is level 4 evidence (based on 1 case series: Benzel & Larson 1986a) that thoracolumbar decompression results in improved neurological functioning among individuals with incomplete SCI but not complete SCI.
There is level 4 evidence (based on 1 case series: Hu et al. 1993) that there is no difference in neurological improvement after thoracolumbar decompression by either an anterior or posterior approach.
There is level 4 evidence (based on 1 pre-post study: Beisse et al. 2005) that endoscopic thoracolumbar surgery results in improved neurologic outcomes for both motor complete and incomplete SCI, although those with incomplete injuries have greater rates of improvement.
There is level 4 evidence (based on 1 case series: Rahimi-Movaghar et al. 2006) that decompression of lumbar burst injuries with associated conus injuries results in neurological improvement and recovery of adjacent nerve root.
