The sacral plexus is one of the major nerve plexuses in the body. A nerve plexus is the area where the nerves branch out and rejoin. Although there are almost 100 nerve plexuses in the body, five are considered major. They include the sacral, cervical, brachial, solar, and lumbar plexus.
The cervical plexus services the shoulders, neck, and head. The brachial plexus provides nerves for the shoulders, chest, arms, and hands. The solar plexus provides sensory nerves for the internal organs, and the lumbar plexus provides nerves to the back, abdomen and lower body.
The sacral plexus is located in the back of the pelvis, and provides the nerves for the pelvic area, genitals, and buttocks. It also provides some of the nerves for the legs and feet. Since the sacral and lumbar plexus provide nerves for many of the same areas, they are often combined and called the lumbosacral plexus.
Due to the effect that the sacral nerves have on the lower body, an illness that affects the plexus can cause serious problems. There are several ways that the sacral region can develop problems, including injury, autoimmune responses, or cancer. Regardless of the cause, the symptoms are similar. There is typically weakness or pain as well as a loss of sensation in the lower body. The symptoms may affect the entire area serviced by the sacral plexus, or only parts of the area.
A diagnosis of problems with the sacral plexus is typically made when a physician notes that the affected body parts are all confined to the area serviced by the sacral plexus. An electromyography can confirm the diagnosis. The physician may then order a magnetic resonance imaging test (MRI) to determine the cause of the problem. The MRI will detect any tumors that may be pressing on the nerve bundles, causing problems.
Patients going through treatment for cancer are also at risk for damage to the sacral plexus due to injury caused by radiation therapy. The therapy, even when directed at other parts of the body, may damage the nerves of the sacral plexus. Diabetics with uncontrolled high blood sugar may also suffer from damage to the sacral plexus. In this case, treatment is possible by bringing blood sugar levels under control.