The sciatic nerve is formed by nerve roots coming out of the spinal cord into the lower back. It is about as thick as your thumb, and it innovates all the way through your buttock, down the back of your legs, into your ankle and foot. When the nerve root becomes compressed and/or irritated, essentially that sciatic nerve becomes inflamed.
Sciatica is the pain associated with an inflamed sciatic nerve. Chiropractic care can help relieve sciatica. Chiropractors can specifically pinpoint the joints which are causing the compression or irritation on the sciatic nerve through some specific imagining. Then, a chiropractor can essentially apply relief and correction through adjustments and/or physical therapy.
Essentially if you remove the stress from the nerve in the joint, it allows the joint to move better. Once the joint is moving better, it creates less irritation and compression on the nerve. When we have less irritation and compression, the nerve functions without giving off those pain signals.