Hello and welcome to JustAnswer,
The thecal sac is the outermost structure containing the lower end of the spinal cord, but at the level of the thecal sac the spinal cord is no longer a cord, but, rather, a group
Hello and welcome to JustAnswer,
The thecal sac is the outermost structure containing the lower end of the spinal cord, but at the level of the thecal sac the spinal cord is no longer a cord, but, rather, a group of nerves that resemble a 'horse's tail', so at this lower level of the back the spinal cord is often called the 'cauda equina'.
The deformity of your thecal sac is likely caused by a herniated disc, but some thecal sac deformities are congenital (there since birth).
A thecal sac deformity can mean many things, if it is associated with a herniated disc there is a chance that surgery will be recommended. Your physician may refer you to a neurologist or a neurosurgeon to consult and to make decisions about whether anything needs to be done in your particular situation.
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