Model for avulsion injury in the rat brachial plexus using passive acceleration

Abstract

We have developed an experimental model for brachial plexus injuries in the rat that closely simulates the characteristics of human injury. This model produces avulsion injuries in a noninvasive manner. A prototype apparatus was designed that allowed a force to be transmitted to a restrained limb by passive acceleration. Reproducible results were obtained in 32 rats. A significant correlation was found between the test weight and the number of roots avulsed (r = 0.92; P < 0.05). The amount of force also correlated to the pattern of avulsion injury: a 230-g weight produced either C6 (54%), C7 (15%), or C6 and C7 (31%) avulsions; a 330-g weight produced C6 (18%), C7 (9%), or C6 and C7 (73%) avulsions; a 530-g weight produced C5 through C8 (75%) or C6 through T1 (25%) avulsions. This model of brachial plexus injury may be useful to further our understanding of the cellular response to this incapacitating injury and to develop therapeutic strategies with behavioral correlates.

The distribution of brachial plexus lesions after experimental traction: a cadaveric study

“…The results demonstrated that all attachments of spinal nerves to the spine were weaker than postganglionic structures. 24 In 2002, Takai et al stretched the BP of rabbits laterally to study the nerve conduction under load. In their experiments, the compound muscle action potential disappeared with a strain of 8.1%.…”

A New Animal Model of Brachial Plexus Neuralgia Produced by Injection of Cobra Venom into the Lower Trunk in the Rat

“…In the behavioral test, rats were tested 3 days before the operation and 3, 6,9,12,15,20,30, and 60 days after the operation. Individual rats were placed in a transparent plastic cage (20320320 cm) on an elevated wire-mesh floor (1.0 31.0 cm cell), and acclimatized for approximately 15 min or until exploratory behavior ceased.…”

“…A variety of animal models have been established to mimic the features of BP neuropathy. However, most of them require damage to both axon and myelin, simulating the characteristics of nerve root avulsion injury . Furthermore, partial or complete peripheral nerve demyelination can cause sensory disorders .…”

A new cervical nerve root avulsion model using a posterior extra-vertebral approach in rats

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