Lecture 5 Femur Flashcards
Articulation of femur
Proximally - Head of femur with the acetabulum of hip
Distally - condyles with the tibia and patella
Fovea capitis
Small depression in the centre of the femoral head where the ligamentum teres attaches to.
The ligamentum teres artery passes through to supply the femoral head in children.
Femoral neck
Connects head with shaft
Passes inferiorly, posteriorly and laterally at 125 degrees to the shaft (angle smaller in females)
Intertrochanteric line
Connects the greater and lesser trochanters anteriorly
Intertrochanteric crest
Connects the greater and lesser trochanters posteriorly
Linea aspera
Ridge in the posterior femoral shaft
Gluteal tuberosity
Thickened line on the posterior femoral shaft in between the intertrochanteric crest and the upper linear aspera
Where the gluteus maximus inserts
Medial supracondylar ridge
Medial branch of when the lower linear aspera splits.
Ends at the adductor tubercle near the medial condyle.
What separates the medial and lateral condyles?
The intercondylar notch posteriorly
Trochlear (patellofemoral groove) anteriorly
Attachments of the hip capsule
Proximally - outside acetabular labrum
Distally - intertrochanteric line anteriorly
- Femoral neck posteriorly
Longitudinal retinacula
Capsule fibres of the capsule that ascend along the femoral neck anteriorly
Contains blood vessels for the femoral head and neck
Intracapsular ligament
Ligamentum teres
Extracapsular ligaments
Iliofemoral
Pubofemoral
Ischiofemoral
Iliofemoral ligament
Strongest
inverted Y shape
Blends with capsule
Most superior
Screws femoral head into the acetabulum when standing
Prevents backward slippage and hyperextension of the hip
Attachment sites of iliofemoral ligament
Anterior inferior iliac spine
Intertrochanteric line
Pubofemoral ligament and attachment sites
Inferior to iliofemoral ligament
Triangular
origin - superior pubic ramus
Insertion - inferior aspect of the intertrochanteric line
Role of pubofemoral ligament
Prevents excessive abduction and extension of the hip joint
Ischiofemoral ligament
Spiral shaped
Posterior
Weakest
Prevents excessive (internal) medial rotation
origin- ischial body
insretion- Greater trochanter
Transverse acetabular ligament
Formed by the acetabular labrum as it bridges the acetabular notch, making a tunnel.
In which nerves and blood vessels enter the hip joint
6 factors that stabilise the hip joint
- Acetabular labrum (deepens acetabulum)
- Capsule
- Acetabulum
- Extracapsular ligaments
- Ligamentum teres
- Muscles surrounding the hip joint
Relationship between hip muscles and ligaments
Reciprocal:
Anteriorly, ligaments are the strongest so the anterior muscles (medial flexors) are fewer and weaker
Posteriorly, the ligament is weaker therefore the muscles (lateral rotators) are stronger and greater in number.
Muscles that flex the hip
Iliopsoas Assisted by: - Rectus femoris - Sartorius - Pectineus
Muscles that extend the hip
Gluteus maximus Hamstrings: - Semimembranosus - Semitendinosus - Biceps femoris (long head)
Muscles that abduct the hip
Gluteus medius Gluteus minimus Assisted by: - Sartorius - Tensor fascia lata
Muscles that adduct the hip
Adductor longus
Adductor brevis
Adductor magnus
Assisted by:
- Pectineus
- Gracilis
- Obturator externus
Muscles that laterally rotate the hip
Obturator externus Piriformis Obturator internus Superior and inferior gemelli Quadratus femoris
Assisted by:
Gluteus maximus
Sartorius
Muscles that medially rotate the hip
Anterior fibres of Gluteus medius and minimus
Tensor fascia lata
Assisted by:
- adductor brevis
- adductor longus
- superior portion of adductor magnus
- pectineus
What controls the degree of flexion of the hip?
When the knee is flexed, the hamstrings are relaxed which increases the range of flexion at the hip
What limits extension of the hip?
Joint capsule
Iliofemoral ligament
Describe the extracapsular arterial ring
At the base of the femoral neck
Anteriorly - branch of the lateral femoral circumflex artery
Posteriorly - large branch of the medial femoral circumflex artery (branch of profunda femoris artery)
The MFCA and LFCA give rise to the retinacular arteries ( ascending cervical branches)
- travel deep to the hip capsule and synovial membrane of the femoral neck to the femoral head
- Supply metaphysis
Where is the ligamentum teres derived from?
Obturator artery
Consequences of an intracapsular fracture
Disruption of the medial femoral circumflex artery, which disrupts the ascending cervical arteries supplying the femoral head in adults.
Risk of avascular necrosis of the bone
