Surgical decompression within 24 hours of acute spinal cord injury (SCI) improves neurological recovery, and current guidelines on surgical management of SCI are being reviewed and updated as a result. These were the key messages to come out of a presentation by Michael Fehlings (University of Toronto, Toronto, Canada) which won Best Paper at the Global Spine Congress annual meeting (3–6 November 2021, Paris, France).
Speaking to Spinal News International, Fehlings said: “The results of our research highlight the concept of ‘Time is Spine’. The secondary injury cascade which occurs after acute SCI is time-critical and early surgical intervention improves neurological outcomes. We anticipate that the current guideline efforts being undertaken in collaboration with the AO Spine Knowledge Forum Spinal Cord Injury and the Praxis Institute will reflect this.”
The research by Fehlings et al, which was also published in Lancet Neurology, found that surgical decompression within 24 hours boosted patients’ sensorimotor recovery. “The first 24 to 36 hours after injury represent a critical window during which earlier decompressive surgery may augment neurological outcomes. Thereafter, the benefit of timeliness may be lost, likely because of irreversible tissue injury”, write the researchers.
The meta-analysis included patients who underwent decompressive surgery for acute SCI and who were identified from four independent, prospective, multicentre data sources (NACTN SCI registry; STASCIS trial; Sygen trial; NASCIS III study).
Patients were stratified into early (<24 hours) and late (≥24 hours) decompression groups. Neurological outcomes were assessed by American Spinal Injury Association (ASIA) examination. The primary endpoint was change in total motor score at one year. Secondary endpoints included ASIA Impairment Scale (AIS) grade and change in upper extremity motor, lower extremity motor, light touch, and pin prick scores at one year.
A total of 1,548 patients were included in the meta-analysis (mean age 39.1). Patients who underwent early surgical decompression (n=528) experienced greater recovery than the late surgery group (n=1,020) at one year for total motor score (mean difference [MD] 4, 95% confidence interval [CI] 1.7-6.3, p=0.001), light touch score (MD 4.3, 95% CI 1.6-7, p=0.002), and pin prick score (MD 4, 95% CI 1.5-6.6, p=0.002).
The meta-analysis also found that there was a shift toward better AIS grades, indicating less severe impairment, at one year in favour of early decompression (common odds ratio 1.48, 95% CI 1.16-1.89, p=0.002). In patients with cervical SCI, early decompressive surgery resulted in disproportionate motor score improvement in the upper (MD 2.2, p<0.001) over lower limbs (MD 1.3, p=0.115). When time to surgical decompression was modelled as a continuous variable, there was a steep decline in Δtotal motor score with increasing time over the first 24 to 36 hours after injury; thereafter, recovery encountered a ‘floor’. This non-linear relationship was statistically significant (p<0.001).
“These findings have important implications for guideline recommendations, clinical practice, and healthcare policy, which may need to be revised to support and facilitate the expeditious delivery of surgical care for acute SCI,” conclude Fehlings et al.