الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 58 |  |  |
| | | from | 58 | | |
Abstract
The transpsoas approach is a novel technique to treat degenerative lumbar disc disease, it gives access to lumbar disc without disrupting the paraspinal muscle and posterior elements.
The limitation of that approach is lumbar plexus which is embeded inside psoas muscle. Knowledge of the anatomy of lumbar plexus and intraoperative EMG is curial during performing this approach.
This cadaveric study was done to define the safe entry zone in psoas muscle. The safe working zone for performing transpsoas approach is defined by the absence of crossing a lumbar plexus branch. We found zone 2 and 3 in L1-2 and L3-4 are safe zones. The location of the genitofemoral nerve was responsible for a narrowing of the safe zone at L2-L3 level making zone 2 not safe and risky to injury of the genitofemoral nerve. Therefore, zone 3 is only safe at level L2-3. However, at level L4-5 the slight ventral migration of lumbar plexus mainly femoral nerve responsible for making zone 2 is the safe zone at this level.
We observed some differences regarding the safe working zone. The small size of cadaveric specimens used in this anatomical study probably gives us the explanation of these differences. Another important point is the fact that there is differences between cadaveric specimens and patients concerning the tissue planes and flexibility.