Introduction: We showed that, after traumatic spinal cord injury (TSCI), the injured cord is compressed by dura . Here we show that laminectomy + duroplasty decompress the injured cord more effectively than laminectomy alone.
Methods: Open label, prospective trial. 21 patients with acute, severe TSCI (AIS A – C) had re-alignment of the fracture and surgical fixation within 72 hours. 11 patients had laminectomy (laminectomy group) and 10 had laminectomy and duroplasty (laminectomy + duroplasty group). Primary outcomes were MRI evidence of cord decompression (increase in intradural space, presence of cerebrospinal fluid around the injured cord) and spinal cord physiology (intraspinal pressure (ISP), spinal cord perfusion pressure (SCPP), spinal vascular pressure reactivity index (sPRx)). ISP was monitored from a pressure probe placed intradurally at the injury site and arterial blood pressure from a catheter placed in the radial artery. SCPP = mean arterial pressure minus ISP. sPRx is the running correlation coefficient between ISP and arterial blood pressure.
Results: The laminectomy and laminectomy + duroplasty groups were well matched. Compared with the laminectomy group, the laminectomy + duroplasty group had greater increase in intradural space at the injury site (50 % vs. 20 %, P< 0.05) and more effective decompression of the injured cord (78 % vs. 0 % had MRI CSF signal round the injured cord, P<0.01). In the laminectomy + duroplasty group, mean ISP was lower (12.7 vs. 18.0 mmHg, P<0.01), mean SCPP higher (83.1 vs. 66.8 mmHg, P<0.05) and mean sPRx lower (0.04 vs. 0.14, P<0.01), i.e. improved vascular pressure reactivity, compared with the laminectomy group. Laminectomy + duroplasty caused cerebrospinal fluid leak that settled with lumbar drain in 1 patient and pseudomeningocele that resolved completely in 5 patients.
Conclusions: After TSCI, laminectomy + duroplasty improves spinal cord radiological and physiological parameters more effectively than laminectomy.
Patient Care: Laminectomy + duroplasty improve spinal cord perfusion of the injured spinal cord and may reduce secondary injury.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Appreciate that the dura causes spinal cord compression after injury, 2) Decsribe the effect of laminectomy after spinal cord injury, 2) Describe the effect of laminectomy and duroplasty after spinal cord injury.
References: 1. Werndle MC et al. Monitoring of spinal cord perfusion pressure in acute spinal cord injury. Crit Care Med 2014;42:646-55.