Variations in the L4 and L5 Ventral Rami with Iliolumbar Ligaments in 14 Cadavers

Iliolumbar ligaments(ILLs) stabilize the lower back. It's two separate parts include the superior and inferior bands. The location of the iliolumbar ligaments (ILLs) is between the iliac crest to transverse process of L4 and L5. The nerves from the L4 and L5 ventral rami pass around the ILLs. The goal of this study is to determine the ligaments and nerves variations of the area to understand of the illiolumbar ligament syndrome and to prevent diagnostic errors and surgical mistakes. This cadaver study examined 14 fixed cadavers from 2012 to 2016. The cadavers were dissected in supine position through the retroperitoneal space. After kidney removal, the iliac crest and psoas muscle were exposed. The obturator nerve, femoral nerve, and lumbosacral trunk (LST) were exposed with ILLs after gentle remove of psoas muscle. Six cadavers showed the obturator and femoral nerves that traveled anterior to both bends of the ILLs and the LST passed posterior to the inferior band of ILLs. Three cadavers showed the obturator and femoral nerves travelling anterior to the ILLs, and L4 of LST anterior to the superior band of the ILLs, and L5 of LST travelling posterior to the inferior band of ILLs. Three cadavers showed the obturator and femoral nerves travelling anterior to the ILLs and the LST passed between the superior and inferior bands of the ILLs. One cadaver showed the obturtor and femoral nerves travelling anterior to the ILLs, and the L4 of LST passed between the superior and inferior bands of the ILLs, and L5 of LST travelling posterior to the ILLs. One cadaver showed the femoral nerve travelling anterior to the ILLs and the L4 of the obturator nerve and the LST travelling between the superior and inferior bands of the ILLs and the L5 of LST travelling posterior to the ILLs. These anatomical variations amongst the individuals are relevant for surgical procedures and the disparity in location of the L4 and L5 ventral ramus nerves may explain the different symptoms of the illiolumbar ligament syndrome.This is in the retro peritoneal space after remove of psoas muscle. QL(Quadratus Lumborum m.), F(Femoral nerve), O(Obturator nerve), L4 LST(L4 Lumbosacral trunk), SB(Superior Band of Iliolumbar ligaments).This is after remove the femoral and obturator nerve. QL(Quadratus Lumborum), SB(Superior Band of iliolumbar ligaments), IB(Inferior Band of iliolumbar ligaments), L4 LST(L4 Lumbosacral trunk), L5 LST(L5 Lumbosacral trunk)