Reattaching Limbs: A Nerve Regeneration Journey

1. Neurons versus Nerves Section C Module 3

2. Reattaching Limbs • John Thomas lost his arms in a farming accident when he was 18 • Doctors reattached his arms and after 3 years of physical therapy and 15 operations he could raise both arms, make fists, and grip with his hands • Doctors have also attached donor hands to severed hands

3. Peripheral Nervous System • Severed can be reattached because they are part of the peripheral nervous system • Peripheral nervous system is made up of nerves, which are located through out the body except in the brain and spinal cord • Nerves are string like bundles of axons and dendrites that come from the spinal cord and are held together by connective tissue • Nerves can regrow or reattach if severed or damaged • Limp transplants are risky because a person must take drugs long-term to suppress his or her own immune system which will try to fight the “foreign” things

4. Central Nervous System • Central Nervous system is the neurons located in the brain and spinal cord • The adult brain has a limited capacity to grow new neurons and a limited ability to make new connections (damaged neurons usually die and are not replaced) • People who damage or severe their spinal cord experience loss of sensation and or motor movement • New research has been able to regrow axons by using tubes made from peripheral nerves to guide the growth and new connects with nervous system