Vascular Supply of proximal femur changes as the age advances and has clinical significance as its injury can leads to avascular necrosis of femoral head.
It is important in pathogenesis of Perthe’s disease.
At base of femoral neck and at the level of capsular attachment, extracapsular ring of attachment is formed. In which,
- Posterior portion is formed by Medial circumflex artery
- Anterior portion is formed by lateral circumflex artery
Branches of the ring arises at regular interval
Blood flows upward to femoral neck and head and downward laterally to tronchanter/ base of neck
Ascending branches from arterial ring will penetrate the capsule along IT line
It pass upward to synovial reflection towards junction of articular cartilage and femoral neck where it forms the intraarticular subsynovial arterial ring forms (circulus articulis vasculosus of hunter)
Arteries of ligamentum teres generally arise form
- Obturator artery
- Medial circumflex femoral artery
Medial circumflex femoral artery
Medial circumflex femoral artery arises directly from femoral artery/ profundus (at the point of origin).
Branch of its, lateral ascending cervical artery which courses upward to the superior surface of neck. After giving metaphyseal vessel to neck it sends prominent vessels called the lateral epiphyseal vessels
Lateral circumflex femoral artery
Lateral circumflex femoral artery gives branches, called
Ascending cervical arteries
- Retinacular arteries
- Lateral and medial metaphyseal arteries
- Rami nutricii capitis
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Derived from the extracapsular arterial ring
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Penetrate capsule at the base of neck
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Pass beneath synovium
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Branches supply to metaphysis and epiphysis
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Epiphyseal branches crosses epiphyseal plate
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Supply to secondary ossification centre.
Vascular arrangement at birth and variation with advancing growth
Blood supply of head is derived from 3 sources:
Medial Ascending cervical vessels ( Inferior metaphyseal of trueta)
- 6- 15 straight vessels: vertically to top of head
- Cauliflower like arrangement of capillaries
Lateral ascending cervical vessels(Lateral epiphyseal of trueta)
- Consist of large group of vessels
- Horizontally to centre of head
- Cauliflower like arrangement of capillaries
Vessels of ligamentum teres
- Supply only limited area at birth
- Radiating (like laural leaf) in character
Phase 1: At birth
Vessels coming from lateral side of head will course horizontally towards medial side
Vessels coming from top of ossified shaft will course vertically through cartilaginous head
Vessels from the ligamentum teres are insignificant/absent
Phase 2: Infantile (4 month-4 years)
At 4 months, epiphyseal ossification begins
Blood supply starts from ascending cervical arteries
Metaphyseal arteries decreases in number (growth plate starts developing)
Lateral epiphyseal arteries has a Major role
Phase 3: Intermediate (4-7 years)
Epiphyseal plate will form a major barrier for blood supply
Only source available is Lateral epiphyseal Vessels
Phase 4: Pre-adolescence (9-10 years)
After 7 years, ligamentum teres vessels become more prominent which extend deeper into epiphysis and anastomosis with lateral epiphyseal vessels
These are termed as medial epiphyseal arteries.
Phase 5:Adolescent Period
At puberty, trochanter has ossified
Lateral epiphyseal vessels will contribute as a major source
Ligamentum teres become increasingly prominent
Phase 6: Adult period
Lateral epiphyseal artery will supply major epiphysis portion
Inferior metaphyseal artery: 2/3rd of the metaphysis tissue lies within femoral head
Round Femoral Head: Epiphysis ( above scar) + metaphysis extending from femoral neck
