The medial and lateral femoral circumflex arteries are the primary blood suppliers to the adult femoral head. The medial femoral circumflex artery courses behind the femoral neck and gives rise to the extracapsular arterial ring at the base of the neck. The lateral femoral circumflex artery courses along the anterior femoral neck. In children, the ligamentum teres artery also contributes significantly to femoral head blood supply, but its importance decreases with age as the medial femoral circumflex artery becomes the predominant supplier by age 8.

1. Blood supply of head of
femur

2. Aorta
Abdominal aorta Internal iliac artery
External iliac artery
Profunda femoris artery
Femoral artery
Lateral circumflex femoral artery
Obturator artery
Extracapsular anastomosis
Medial circumflex femoral artery
Superior
Anterior
Inferior
Retinacular artery
Artery to ligament of teres
Intracapsular anastomosis
Supply head of femur

4. Medial femoral circumflex (MFCA):
Course: between pectineus and psoas, then posterior to femoral neck
under quadratus femoris.
Major blood supply to adult femoral head.
Major contributor to extracapsular ring / anastomosis.

6. Lateral femoral circumflex (LFCA):
Course:
• Deep to sartorius and rectus femoris.
• Ascends anterior femoral neck
• Across proximal femur to GT.
Under rectus femoris.
Less significant blood supply in adult femoral head.
At risk in anterolateral approach to hip.

7. Extracapsular ring:
Formed at the base of femoral neck primarily from branches of MFCA and LFCA.
Lateral branch  from ring laterally toward GT  supply greater trochanter.
Ascending cervical arteries  along extracapsular femoral neck branch from
extracapsular ring.
Retinacular arteries  along intracapsular femoral neck  intracapsular continuation
of cervical arteries from a 2nd intracapsular ring at base of head.

8. Subsynovial intracapsular arterial ring:
Formed at the base of the femoral head.
Epiphyseal arteries and lateral epiphyseal artery:
Enter bone at border of articular surface in posterosuperior neck.
Will form intraosseous anastomoses.
Lat. Epiphyseal supplies most of WB femoral head.

9. Obturator Artery:
Artery of ligamentum teres  Through ligamentum teres to fovea  Minimal
supply to the adult femoral head.
Medial epiphyseal artery  Interosseous terminal branches  Anastomose with
lateral epiphyseal arteries.

10. Paediatric femoral head blood supply:
• 0-4yr  MFCA, LFCA, and ligamentum teres artery;
• 4-8yr: mostly MFCA, minimal LFCA and ligamentum teres artery;
• 8yrs: MFCA is predominant.

12. Paediatric femoral head blood supply:

13. Paediatric femoral head blood supply:

14. Paediatric femoral head blood supply:

15. Paediatric femoral head blood supply: