© 2015 Elsevier Ltd. Introduction With a subvastus approach to the femur, the vessels that perforate the lateral intermuscular septum (LISP-vessels) must be ligated. The effect on the blood supply to the femur remains unclear. The purpose of the current study was to investigate the effect of ligation of the LISP-Vessels on the blood supply and to examine the anatomy of the LISP-vessels and the anastomoses around the femur. Materials In six human cadavers the LISP vessels were ligated by a lateral subvastus approach on one side. The contralateral side served as control group. After bilateral injection of different coloured silicon dyes into the lateral and medial circumflex femoral artery (green), deep femoral artery (red) and the superficial femoral artery (blue) dissection was performed bilaterally. The arterial perfusion on both sides was compared and the anatomy of the LISP vessels studied. Results The medullary perfusion of the femur was not altered by the ligation of the LISP vessels. It did also not lead to a decrease in periosteal vessel filling. The LISP vessels were shown to be a part of a complex and rich anastomotic network and play an important role in the perfusion of the femur and quadriceps muscle group. The ligature could be compensated for by this anastomotic network. Branches to the periosteum separate from the LISP vessels immediately after perforating the lateral intermuscular septum. The linea aspera turned out to be an important area for the femoral blood supply. Discussion and conclusions Exposure of the femur through a lateral subvastus approach with ligation of LISP vessels causes a certain degree of soft tissue trauma. However, by using a gentle surgical technique the periostal perfusion of the femur can be preserved by a potent anastomotic network after ligation of the LISP vessels if they are not ligated to close to the lateral intermuscular septum and the linea aspera is not unnecessarily exposed.