This study investigates and defines the topographic
anatomy of the medial femoral circumflex artery (MFCA) terminal
branches supplying the femoral head (FH). Gross dissection of 14
fresh–frozen cadaveric hips was undertaken to determine the extra
and intracapsular course of the MFCA’s terminal branches. A constant
branch arising from the transverse MFCA (inferior retinacular artery;
IRA) penetrates the capsule at the level of the anteroinferior neck,
then courses obliquely within the fibrous prolongation of the capsule
wall (inferior retinacula of Weitbrecht), elevated from the neck,
to the posteroinferior femoral head–neck junction. This vessel has
a mean of five (three to nine) terminal branches, of which the majority
penetrate posteriorly. Branches from the ascending MFCA entered
the femoral capsular attachment posteriorly, running deep to the
synovium, through the neck, and terminating in two branches. The
deep MFCA penetrates the posterosuperior femoral capsular. Once
intracapsular, it divides into a mean of six (four to nine) terminal
branches running deep to the synovium, within the superior retinacula
of Weitbrecht of which 80% are posterior. Our study defines the
exact anatomical location of the vessels, arising from the MFCA
and supplying the FH. The IRA is in an elevated position from the
femoral neck and may be protected from injury during fracture of
the femoral neck. We present vascular ‘danger zones’ that may help
avoid iatrogenic vascular injury during surgical interventions about
the hip. Cite this article:
We aimed to quantify the relative contributions of the medial
femoral circumflex artery (MFCA) and lateral femoral circumflex
artery (LFCA) to the arterial supply of the head and neck of the
femur. We acquired ten cadaveric pelvises. In each of these, one hip
was randomly assigned as experimental and the other as a matched
control. The MFCA and LFCA were cannulated bilaterally. The hips
were designated LFCA-experimental or MFCA-experimental and underwent
quantitative MRI using a 2 mm slice thickness before and after injection
of MRI-contrast diluted 3:1 with saline (15 ml Gd-DTPA) into either
the LFCA or MFCA. The contralateral control hips had 15 ml of contrast
solution injected into the root of each artery. Next, the MFCA and
LFCA were injected with a mixture of polyurethane and barium sulfate
(33%) and their extra-and intra-arterial course identified by CT
imaging and dissection.Aims
Materials and Methods