In recent years, some taxonomic controversy has occurred over the genus of North American rat snakes. Based on mitochondrial DNA, Utiger et al. (2002) showed that North American rat snakes of the genus Elaphe, along with closely related genera such as Pituophis and Lampropeltis, form a monophyletic group separate from Old World members of the genus.
A pinched nerve is a type of injury or damage to a nerve or a group of nerves. The injury can result from compression, constriction, or stretching. A pinched nerve can lead to other conditions and cause temporary or permanent damage depending on the extent of the injury. pinched nerve is a type of injury or damage to a nerve or a group of nerves. The injury can result from compression, constriction, or stretching. A pinched nerve can lead to other conditions and cause temporary or permanent damage depending on the extent of the injury.
Close testing of radial nerve injuries is required because this type of injury can mimic more serious disorders of the central nervous system (the brain and spinal cord) such as stroke. These injuries also often cause more weakness of muscle extension than flexion. The sparing of the triceps, sensory loss along the back of the arm, and especially brachioradialis weakness can help distinguish radial nerve injury at the spiral groove from problems of the brain or spinal cord.