Spinal nerves exit (and enter) through the intervertebral foramen. The spinal nerve consist of two main divisions (anterior/motor and posterior/sensory).
A patient’s symptoms are often related to whether the anterior division or posterior division is compromised. This can occur as a soft compromise (like a disc bulge, or herniation) or by an inflammatory process (like chemical radiculitis) or by a hard compromise like bony stenosis due to osteophytic compression.
Tingling or numbness is a symptom when the sensory division (or posterior division of the spinal nerve) is affected.
Clinically, if the spinal nerve is compressed from a posterior lesion, and the nerve is compromised, the patient will present with a sensory type symptom like tingling or numbness.
On the other hand, if the anterior division is compressed from an anterior lesion, the patient can present with motor symptoms like weakness.
Dynamic Disc Designs has developed spinal nerves to include both divisions to enable the doctor to explain and correlate the patient’s symptoms associated with spinal nerve compromise. All other spine models on the market do not represent the spinal nerves accurately.
In behind the scenes at Dynamic Disc Designs Corp. the research and development in the accurate representation of the spinal nerve anatomy came, in part, directly from one of Dr. Fryer (Chief Innovation Officer) mentors. Prior to the final product manufacturing, Dr. David Panzer provided guidance in the proper placement the spinal nerves in both the Professional LxH Model and the Academic LxH Model . On the right aspect of the cauda equina in these lumbar models, the dural sheath has been removed to show the two separate divisions of the exiting (and entering) spinal nerves.
The most common L5 spinal nerve root compression is a result of a posterior-lateral herniation at the L4-5 level. The developed cauda equina extends superiorly to demonstrate the descending nature of the spinal nerves and to show which nerve would be affected both at the L4-5 and L3-4 levels.