Brief Answer: Hi and welcome to HCM Detailed Answer: Such injuries may interfere with bowel and anal sphincter function since nerves responsible for bowel movements are in this area. Usually nerve damage happens after vertebral fractures,but even if there was just contusion there could be oedema which presses nerves around lumbar spine. This could cause symptoms that you are mentioning,but it should improve in several days. Just in case, you should do xrays to check is there fracture and doctor should perform digitorectal exam. Although, this is still not something to worry about. It can be just coincidence that you have constipation which could be aggravated by this fall. You should drink plenty of fluids and eat high fibre food. if there is no improvement you should try with glycerine supositories and laxatives. If you have tingling sensation in legs, loss of sensation, blood in stool,you should visit doctor as soon as possible. Wish you good health. Feel free to ask.

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