Efficacy of Ultra-Early (< 12 h), Early (12-24 h), and Late (>24-138.5 h) Surgery with Magnetic Resonance Imaging-Confirmed Decompression in American Spinal Injury Association Impairment Scale Grades A, B, and C Cervical Spinal Cord Injury

Abstract

In cervical traumatic spinal cord injury (TSCI), the therapeutic effect of timing of surgery on neurological recovery remains uncertain. Additionally, the relationship between extent of decompression, imaging biomarker evidence of injury severity, and outcome is incompletely understood. We investigated the effect of timing of decompression on long-term neurological outcome in patients with complete spinal cord decompression confirmed on postoperative magnetic resonance imaging (MRI). American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade conversion was determined in 72 AIS grades A, B, and C patients 6 months after confirmed decompression. Thirty-two patients underwent decompressive surgery ultra-early (< 12 h), 25 underwent decompressive surgery early (12-24 h), and 15 underwent decompressive surgery late (> 24-138.5 h) after injury. Age, gender, injury mechanism, intramedullary lesion length (IMLL) on MRI, admission ASIA motor score, and surgical technique were not statistically different among groups. Motor complete patients (p = 0.009) and those with fracture dislocations (p = 0.01) tended to be operated on earlier. Improvement of one grade or more was present in 55.6% of AIS grade A, 60.9% of AIS grade B, and 86.4% of AIS grade C patients. Admission AIS motor score (p = 0.0004) and pre-operative IMLL (p = 0.00001) were the strongest predictors of neurological outcome. AIS grade improvement occurred in 65.6%, 60%, and 80% of patients who underwent decompression ultra-early, early, and late, respectively (p = 0.424). Multiple regression analysis revealed that IMLL was the only significant variable predictive of AIS grade conversion to a better grade (odds ratio, 0.908; confidence interval [CI], 0.862-0.957; p < 0.001). We conclude that in patients with post-operative MRI confirmation of complete decompression following cervical TSCI, pre-operative IMLL, not the timing of surgery, determines long-term neurological outcome.

Keywords: MRI; SCI; decompression; outcome; timing of surgery.

FIG. 1.

(A–D) Midsagittal computed tomography (CT) and magnetic resonance imaging (MRI) of a 19-year-old man involved in an automobile accident who was admitted 30 min later to the trauma resuscitation unit (TRU) with a C5 compression tear-drop fracture (arrow); American Spinal Injury Association (ASIA) motor score of 21, and ASIA Impairment Scale (AIS) grade B; intramedullary lesion length (IMLL) at admission was 27.8 mm. A C5 corpectomy was performed 6 h after the accident, which completely decompressed the spinal cord. MRI 34.5 h after surgery indicated an IMLL of 34.4 mm. One year following the accident, his ASIA motor score was 64 and he was AIS grade D. (E–H) Midsagittal CT and MRI of a 42-year-old man who had a mechanical fall and was admitted 30 min later to the TRU with from spinal stenosis and possible extension injury (arrow); ASIA motor score was 8 and AIS grade was A; IMLL at admission was 42.2 mm. He underwent C4 corpectomy and C3–C5 laminectomy with fusion 13 h after the accident, with complete spinal cord decompression. MRI 23 h after surgery indicated an IMLL of 30.9 mm. Six months following the accident, his ASIA motor score remained 8 and he was AIS grade A. (I–L) Midsagittal CT and MRI of a 53-year-old man who had a mechanical fall and was admitted 10.5 h later to the TRU with a C3/4 extension injury (arrow); ASIA motor score was 33 and AIS grade was C; IMLL at admission was 20.3 mm. He underwent discectomy and fusion at C3/4, 36 h after the accident, with complete spinal cord decompression. MRI 49.8 h after surgery indicated an IMLL of 49.6 mm. Fifty-seven months following the accident, his ASIA motor score was 91 and he was AIS grade D.