Spinal Cord Compression Studies

Abstract

IT IS CLINICALLY important to determine how long the spinal cord may be compressed without precluding functional recovery, because it would lead to more rational and standardized treatment. One would expect the time to be short because of the vulnerability of nerve tissue to mechanical distortion and anoxia. Allen* attempted to answer this question by producing contusion of the spinal cord of dogs. His technique was to drop known weights from known heights on the spinal cord. The degree of the impact was measured in gram-centimeters. Allen believed that the edema following the impact reached its maximum about four hours after the injury. He concluded that if the spinal cord compression caused by the edema could be prevented, the spinal cord might recover some function. Accordingly, he advised midline posterior incision of the spinal cord through the contused segment to drain and release the intramedullary pressure. He made such incisions in dogs two hours after injury by a force known to produce complete paralysis. He reported that he could thus avert the disintegration of cord tissue that invariably occurred in the control dogs in which the spinal cord was not incised.A valid objection to Allen's interpretation of these changes is well expressed by Thompson 12 :There is no doubt that the substance of the cord is clearer and better preserved in the incised than in the nonincised specimen but there is such a decrease in transverse area of the cord that we can't help feeling that the diffluent tissue which escaped from the incision carried with it a considerable amount of nervous tissue which had not been seriously injured and which might have been expected reasonably to have recovered if it had not been disturbed. While it lies in the substance of the cord it acts as support to the uninjured tissue surrounding it. Evacuation removes this support and the walls of the cavity cave in like the sides of a sand pit or the banks of a river when the waters recede. On these grounds we believe that the evacuation is not without its drawbacks and its dangers.Allen's experiments have fallen short, therefore, of solving our problem.

Chronic Spinal Compression Model in Minipigs: A Systematic Behavioral, Qualitative, and Quantitative Neuropathological Study

“…These animals did not recover their motor function qualitatively or quantitatively over the 9-month recovery period. In accordance with prior reports of severe SCI in dogs (Fukuda et al, 2005; Tarlov, 1954), this confirms that in the minipig model a severe trauma produces comparable stable neurological dysfunction, and the degree of spontaneous recovery is limited. The recovery is characterized by only modest improvement of movement in affected extremities, but with a persisting presence of functionally defined paraplegia (i.e., inability of the animals to stand and bear weight).…”

“…While no systematic axonal quantification was performed in those studies, the development of extensive local tissue cavitations and loss of gray and white matter integrity at the injury site was seen in animals after severe trauma. These histopathological changes corresponded with stable neurological deficits (paralysis), which persisted up to 3 months after injury (Allen, 1911; Tarlov, 1954; Tarlov and Klinger, 1954). In a more recent study, a similar epidural-balloon-compression model as described by Tarlov (Tarlov, 1954) has been reported in dogs (Fukuda et al, 2005).…”

Chronic Spinal Compression Model in Minipigs: A Systematic Behavioral, Qualitative, and Quantitative Neuropathological Study

“…These animals did not recover their motor function qualitatively or quantitatively over the 9-month recovery period. In accordance with prior reports of severe SCI in dogs (Fukuda et al, 2005; Tarlov, 1954), this confirms that in the minipig model a severe trauma produces comparable stable neurological dysfunction, and the degree of spontaneous recovery is limited. The recovery is characterized by only modest improvement of movement in affected extremities, but with a persisting presence of functionally defined paraplegia (i.e., inability of the animals to stand and bear weight).…”

“…While no systematic axonal quantification was performed in those studies, the development of extensive local tissue cavitations and loss of gray and white matter integrity at the injury site was seen in animals after severe trauma. These histopathological changes corresponded with stable neurological deficits (paralysis), which persisted up to 3 months after injury (Allen, 1911; Tarlov, 1954; Tarlov and Klinger, 1954). In a more recent study, a similar epidural-balloon-compression model as described by Tarlov (Tarlov, 1954) has been reported in dogs (Fukuda et al, 2005).…”

A No-Laminectomy Spinal Cord Compression Injury Model in Mice

“…Of note, all methods of neurologic evaluation detected a duration-dependent effect of SCC on neurologic function, despite relatively small sample sizes (n 5 5-9). Our findings of a duration dependent effect of SCC on histologic/behavioral injury are consistent SCC studies performed in other species (Tarlov et al, 1953;Tarlov and Klinger, 1954;Guha et al, 1987;Dolan et al, 1980). However, in both the BBB and rotarod tests, which were measured serially over the 14-day recovery interval, a marked improvement in function was observed, particularly in the groups with longer SCC intervals.…”

Vertebral fracture and dislocation patterns, location of injuries, and 6-month clinical outcomes in cats: A retrospective study

“…In the surgical group, focusing on timing before surgery, there were many previous studies in humans (Kishan et al, 2005;Fehlings and Wilson, 2010;Dvorak et al, 2015;El Tecle et al, 2016;Glennie et al, 2017), as well as in dogs and cats, that revealed that performing the operation as fast as possible, typically <72 h, results in outstanding outcomes. However, most studies have focused on the context of SCI caused by intervertebral disc herniation (Tarlov and Klinger, 1954;Carlson et al, 1997;Davis and Brown, 2002;Rabinowitz et al, 2008). In this study, two cats (50%, 2/4) had surgery longer than 72 h after being injured, and their outcomes were better than before surgery.…”

Chronic Spinal Compression Model in Minipigs: A Systematic Behavioral, Qualitative, and Quantitative Neuropathological Study

“…These animals did not recover their motor function qualitatively or quantitatively over the 9-month recovery period. In accordance with prior reports of severe SCI in dogs (Fukuda et al, 2005; Tarlov, 1954), this confirms that in the minipig model a severe trauma produces comparable stable neurological dysfunction, and the degree of spontaneous recovery is limited. The recovery is characterized by only modest improvement of movement in affected extremities, but with a persisting presence of functionally defined paraplegia (i.e., inability of the animals to stand and bear weight).…”

“…While no systematic axonal quantification was performed in those studies, the development of extensive local tissue cavitations and loss of gray and white matter integrity at the injury site was seen in animals after severe trauma. These histopathological changes corresponded with stable neurological deficits (paralysis), which persisted up to 3 months after injury (Allen, 1911; Tarlov, 1954; Tarlov and Klinger, 1954). In a more recent study, a similar epidural-balloon-compression model as described by Tarlov (Tarlov, 1954) has been reported in dogs (Fukuda et al, 2005).…”

A No-Laminectomy Spinal Cord Compression Injury Model in Mice

“…Of note, all methods of neurologic evaluation detected a duration-dependent effect of SCC on neurologic function, despite relatively small sample sizes (n 5 5-9). Our findings of a duration dependent effect of SCC on histologic/behavioral injury are consistent SCC studies performed in other species (Tarlov et al, 1953;Tarlov and Klinger, 1954;Guha et al, 1987;Dolan et al, 1980). However, in both the BBB and rotarod tests, which were measured serially over the 14-day recovery interval, a marked improvement in function was observed, particularly in the groups with longer SCC intervals.…”

Vertebral fracture and dislocation patterns, location of injuries, and 6-month clinical outcomes in cats: A retrospective study

“…In the surgical group, focusing on timing before surgery, there were many previous studies in humans (Kishan et al, 2005;Fehlings and Wilson, 2010;Dvorak et al, 2015;El Tecle et al, 2016;Glennie et al, 2017), as well as in dogs and cats, that revealed that performing the operation as fast as possible, typically <72 h, results in outstanding outcomes. However, most studies have focused on the context of SCI caused by intervertebral disc herniation (Tarlov and Klinger, 1954;Carlson et al, 1997;Davis and Brown, 2002;Rabinowitz et al, 2008). In this study, two cats (50%, 2/4) had surgery longer than 72 h after being injured, and their outcomes were better than before surgery.…”

Chronic Spinal Compression Model in Minipigs: A Systematic Behavioral, Qualitative, and Quantitative Neuropathological Study

“…These animals did not recover their motor function qualitatively or quantitatively over the 9-month recovery period. In accordance with prior reports of severe SCI in dogs (Fukuda et al, 2005; Tarlov, 1954), this confirms that in the minipig model a severe trauma produces comparable stable neurological dysfunction, and the degree of spontaneous recovery is limited. The recovery is characterized by only modest improvement of movement in affected extremities, but with a persisting presence of functionally defined paraplegia (i.e., inability of the animals to stand and bear weight).…”

“…While no systematic axonal quantification was performed in those studies, the development of extensive local tissue cavitations and loss of gray and white matter integrity at the injury site was seen in animals after severe trauma. These histopathological changes corresponded with stable neurological deficits (paralysis), which persisted up to 3 months after injury (Allen, 1911; Tarlov, 1954; Tarlov and Klinger, 1954). In a more recent study, a similar epidural-balloon-compression model as described by Tarlov (Tarlov, 1954) has been reported in dogs (Fukuda et al, 2005).…”

A No-Laminectomy Spinal Cord Compression Injury Model in Mice

“…Of note, all methods of neurologic evaluation detected a duration-dependent effect of SCC on neurologic function, despite relatively small sample sizes (n 5 5-9). Our findings of a duration dependent effect of SCC on histologic/behavioral injury are consistent SCC studies performed in other species (Tarlov et al, 1953;Tarlov and Klinger, 1954;Guha et al, 1987;Dolan et al, 1980). However, in both the BBB and rotarod tests, which were measured serially over the 14-day recovery interval, a marked improvement in function was observed, particularly in the groups with longer SCC intervals.…”

Vertebral fracture and dislocation patterns, location of injuries, and 6-month clinical outcomes in cats: A retrospective study

“…In the surgical group, focusing on timing before surgery, there were many previous studies in humans (Kishan et al, 2005;Fehlings and Wilson, 2010;Dvorak et al, 2015;El Tecle et al, 2016;Glennie et al, 2017), as well as in dogs and cats, that revealed that performing the operation as fast as possible, typically <72 h, results in outstanding outcomes. However, most studies have focused on the context of SCI caused by intervertebral disc herniation (Tarlov and Klinger, 1954;Carlson et al, 1997;Davis and Brown, 2002;Rabinowitz et al, 2008). In this study, two cats (50%, 2/4) had surgery longer than 72 h after being injured, and their outcomes were better than before surgery.…”