Relieving intraspinal pressure acutely after cervical spinal cord injury improves functional outcomes

Acute traumatic spinal cord injury (tSCI) often results in devastating neurological dysfunction for affected individuals and imposes a substantial financial burden on society worldwide. Current treatment approaches have limited ability to counteract secondary injury expansion and additional cell death. The extent of secondary damage is a result of posttraumatic tissue swelling, edema, vascular damage, and hematoma and these factors contribute to pathological intraspinal pressure (ISP) elevations after trauma. Multiple pharmaceutical and surgical treatment approaches aim to mitigate secondary spinal cord damage, with only few targeting ISP directly. Here, we aimed to characterize the temporal and spatial development of cervical ISP changes after tSCI in a rodent model and assess the subacute and long-term effects of surgical spinal cord decompression (i.e. durotomy) on secondary damage, lesion size and functional recovery. We showed that moderate cervical tSCI resulted in pathological ISP elevations immediately after trauma and during the first 4 h after injury (3.0 ± 1.1 mmHg immediately post-injury vs. 7.9 ± 2.3 mmHg at 4 h post-injury). Durotomy resulted in significant ISP reduction, hematoma size, and increased tissue sparing at two weeks post tSCI compared to tSCI animals without durotomy, accompanied by a significant reduction of apoptosis as quantified by caspase-8 analysis when compared to the cohort without durotomy. In a chronic study, durotomy animals exhibited significantly greater and faster forelimb recovery compared to animals without durotomy (forelimb scores of 17.7 vs. 10.6; p < 0.05 at 4 weeks post injury). Future studies are needed to examine the effects of durotomy on different injury severities.