What is the spinal cord level innervation to the gastrointestinal (GI) tract?

From the Guidelines

The spinal cord level innervation to the gut is primarily controlled by the autonomic nervous system, with sympathetic innervation originating from the thoracolumbar region (T5-L2) and parasympathetic innervation coming from the vagus nerve and the sacral parasympathetic outflow (S2-S4). The autonomic nervous system plays a crucial role in regulating gut function, including motility, secretion, and blood flow. According to a study published in Gut in 2020 1, disorders of the parasympathetic or sympathetic nerves that innervate the gut can indirectly cause gut dysmotility. Some key points to consider about spinal cord level innervation to the gut include:

• Sympathetic innervation generally inhibits gut function, decreasing motility and secretions while constricting blood vessels
• Parasympathetic stimulation enhances digestive functions by increasing motility, stimulating secretions, and dilating blood vessels
• The vagus nerve (cranial nerve X) originates in the brainstem and supplies the foregut and midgut down to the splenic flexure
• The sacral parasympathetic outflow (S2-S4) innervates the hindgut from the distal transverse colon to the upper anal canal Understanding this innervation pattern is crucial for diagnosing and treating various gastrointestinal disorders, as well as for performing procedures like nerve blocks and understanding the effects of spinal cord injuries on gut function, as noted in the study published in Gut in 2020 1.

From the Research

Spinal Cord Level Innervation to the Gut

The spinal cord level innervation to the gut is a complex process that involves the coordination of various nerve pathways.

• The gut is innervated by the autonomic nervous system, which includes the sympathetic and parasympathetic nervous systems 2.
• The sympathetic nervous system is responsible for the "fight or flight" response, while the parasympathetic nervous system is responsible for the "rest and digest" response 2.
• The enteric nervous system, which is often referred to as the "little brain" of the gut, also plays a crucial role in regulating gut function 2.

Neurogenic Bowel Dysfunction

Neurogenic bowel dysfunction is a common complication of spinal cord injury, and it can have a significant impact on quality of life 3, 2, 4, 5.

• The condition is characterized by impaired colonic motility and sphincter dysfunction, which can lead to constipation, fecal incontinence, and other gastrointestinal symptoms 4.
• Treatment of neurogenic bowel dysfunction typically involves a multimodal approach, including dietary changes, pharmacologic and mechanical stimulation, and possibly surgery 4.

Management of Neurogenic Bowel

The management of neurogenic bowel requires a comprehensive approach that takes into account the individual's specific needs and circumstances 5.

• This may involve a combination of different interventions, such as bowel training, dietary changes, and medication 5.
• The goal of management is to maintain health and well-being, promote a good quality of life, and support active, fulfilled lives in the home and community 2.