Effects of early surgical decompression on functional and histological outcomes after severe experimental thoracic spinal cord injury

Abstract

<jats:sec> <jats:title>OBJECTIVE</jats:title> <jats:p>In acute traumatic brain injury, decompressive craniectomy is a common treatment that involves the removal of bone from the cranium to relieve intracranial pressure. The present study investigated whether neurological function following a severe spinal cord injury improves after utilizing either a durotomy to decompress the intradural space and/or a duraplasty to maintain proper flow of cerebrospinal fluid.</jats:p></jats:sec> <jats:sec> <jats:title>METHODS</jats:title> <jats:p>Sixty-four adult female rats (n = 64) were randomly assigned to receive either a 3- or 5-level decompressive laminectomy (Groups A and B), laminectomy + durotomy (Groups C and D), or laminectomy + duraplasty with graft (Group E and F) at 24 hours following a severe thoracic contusion injury (200 kilodynes). Duraplasty involved the use of DuraSeal, a hydrogel dural sealant. Uninjured and injured control groups were included (Groups G, H). Hindlimb locomotor function was assessed by open field locomotor testing (BBB) and CatWalk gait analysis at 35 days postinjury. Bladder function was analyzed and bladder wall thickness was assessed histologically. At 35 days postinjury, mechanical and thermal allodynia were assessed by the Von Frey hair filament and hotplate paw withdrawal tests, respectively. Thereafter, the spinal cords were dissected, examined for gross anomalies at the injury site, and harvested for histological analyses to assess lesion volumes and white matter sparing. ANOVA was used for statistical analyses.</jats:p></jats:sec> <jats:sec> <jats:title>RESULTS</jats:title> <jats:p>There was no significant improvement in motor function recovery in any treatment groups compared with injured controls. CatWalk gait analysis indicated a significant decrease in interlimb coordination in Groups B, C, and D (p &lt; 0.05) and swing speed in Groups A, B, and D. Increased mechanical pain sensitivity was observed in Groups A, C, and F (p &lt; 0.05). Rats in Group C also developed thermal pain hypersensitivity. Examination of spinal cords demonstrated increased lesion volumes in Groups C and F and increased white matter sparing in Group E (p &lt; 0.05). The return of bladder automaticity was similar in all groups. Examination of the injury site during tissue harvest revealed that, in some instances, expansion of the hydrogel dural sealant caused compression of the spinal cord.</jats:p></jats:sec> <jats:sec> <jats:title>CONCLUSIONS</jats:title> <jats:p>Surgical decompression provided no benefit in terms of neurological improvement in the setting of a severe thoracic spinal cord contusion injury in rats at 24 hours postinjury. Decompressive laminectomy and durotomy did not improve motor function recovery, and rats in both of these treatment modalities developed neuropathic pain. Performing a durotomy also led to increased lesion volumes. Placement of DuraSeal was shown to cause compression in some rats in the duraplasty treatment groups. Decompressive duraplasty of 3 levels does not affect functional outcomes after injury but did increase white matter sparing. Decompressive duraplasty of 5 levels led to neuropathic pain development and increased lesion volumes. Further comparison of dural repair techniques is necessary.</jats:p></jats:sec>

Promising neuroprotective strategies for traumatic spinal cord injury with a focus on the differential effects among anatomical levels of injury

“…The popularized phrase coined by the senior author, “Time is spine”, highlights the preclinical 13 , 14 and clinical 15 , 16 success of early surgical decompression, which aims to realign the spinal column and relieve bony or ligamentous spinal cord compression. Decompression of intradural pressure, by durotomy alone or durotomy combined with duraplasty, has also been evaluated in experimental SCI 17 , 18 . Yet mixed results warrant further research on the efficacy and standardization of these practices.…”

Duraplasty of PHBV/PLA/Col membranes promotes axonal regeneration by inhibiting NLRP3 complex and M1 macrophage polarization in rats with spinal cord injury

“…48 Jalan et al suggested that decompressive duraplasty in three levels does not affect functional outcomes after injury, whereas that in five levels may lead to the development of neuropathic pain and increase the volume of lesions. 8 In our research, 4-mm decompressive duraplasty was performed at less than three levels and we noted that neither neuropathic pain development nor increased the volume of lesions. Smith et al suggested that decompression surgery should be performed 4 hours after C5 contusion injury.…”

“…P-P-C4.5 membrane transplantation groups during the observation period. Von Frey filament tests with a gradient of bending forces (6,8,10,15,26,60,100,180, and 300 g) were applied to the hind limbs to determine the paw withdrawal threshold as an indicator of sensory recovery. The cutoff threshold to elicit paw withdrawals in healthy rats was set at 60 g, below which withdrawal responses were considered allodynia.…”

“…6 In an animal model of acute mild cervical SCI, Smith et al demonstrated that durotomy alone showed increased scar and cavity formation, while better functional recovery and decreased lesion size, inflammation, and scar formation following decompression of the intradural space using durotomy and placement of a dural graft compared with decompression with durotomy alone. 7 Duraplasty with allograft or autograft dura substitutes was believed to reduce cavity volume and glia formation, 6,8 but the underlying mechanism has not been investigated.…”

Therapeutic Effect of Curcumin and Methylprednisolone in the Rat Spinal Cord Injury

“…It creates enormous psychological and economic burdens to an individual's family as well as the society as a whole (Guo et al, 2014;Du et al, 2015;Lu et al, 2015;Wang et al, 2016;Yang and Wang, 2015). In the United States, there are approximately 282,000 people suffering from SCI with an average growth of 17,000 cases annually (Jalan et al, 2016). SCI includes primary and secondary injuries.…”