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Flashcards in Femur Deck (70):

Proximal extremity contains 6 structures

- Head
- Neck
- Greater trochanter
- Lesser trochanter
- Intertrochanteric line
- Intertrochanteric crest


Head of femur

- Ball shaped for articulation with hip bone at acetabulum
- 2/3 of structure is spherical and is covered by hyaline cartilage (except fovea "pit")
- Fovea is the site of attachment for the ligament of the head of the femur
- The entire head structure lies in the articular capsule of the hip joint


Neck of femur

- Joins head and shaft of bone
- This creates a femoral angle of inclination
- This angle is greatest at the time of birth
- Sex and body size determine the angle


Normal adult values for femoral angle of inclination

- Male = 125 degrees
- Female = 105 degrees


Angle of declination

- The anterior projection of the neck from the shaft of the femur creates the angle of declination
- The normal value for this is 12 - 14 degrees


Shape and surfaces of neck of femur

- Hour glass shaped (thinnest in middle)
- Two surfaces: anterior and posterior


Anterior surface of neck of femur

- Entirely enclosed in joint capsule of hip joint
- Covex superior to inferior
- Concave side to side
- Many small vascular foramina
- Intertrochanteric line


Intertrochanteric line

- Between greater and lesser trochanters on the anterior surface of neck of femur
- Continuous inferiorly with the spiral line


Posterior surface of neck of femur

- More curved than anterior surface
- Upper 1/2 to 2/3 lies in the joint capsule
- The lower portion is grooved for the tendon of obturator externus
- There are fewer but larger vascular foramina when compared to the anterior surface
- Intertrochanteric crest


Intertrochanteric crest

- Ridge of bone between greater and lesser trochanters
- Where the posterior neck joins the shaft of the femur


Superior border of neck of femur

- Short, thick, courses horizontally
- Ends at greater trochanter


Inferior border of neck of femur

- Long, thin, courses vertically
- Ends at lesser trochanter


Greater trochanter

- Large, irregular, quadrilateral-shaped prominence
- Located at the lateral end of the superior border of the neck of the femur
- Projects laterally and posteriorly
- Contains two surfaces: lateral and medial


Lateral surface of greater trochanter

- Larger, palpable, quadrilateral shaped
- Contains an oblique bony ridge for insertion of the gluteus medius
- Bony ridge divides the lateral surface into two triangular areas, each covered by a trochanteric bursae
- Upper triangle has a bursa for the gluteus medius
- Lower triangle has a bursa for the gluteus maximus


Medial surface of greater trochanter

- Trochanteric fossa is the major feature - a depression for insertion of obturator externus
- The obturator internus tendon inserts on the anterior surface of the trochanteric fossa
- NOTE: the superior and inferior gemelli muscles terminate and insert into the tendon of obturator internus


4 borders of greater trochanter

- Superior
- Inferior
- Anterior
- Posterior

Contain muscle attachment sites


Muscle attachment to superior border of greater trochanter

- Piriformis muscle insertion


Muscle attachment to anterior border of greater trochanter

- Insertion of gluteus minimus


Muscle attachment to inferior border of greater trochanter

Partial origin of vastus lateralis


Muscle attachment to posterior border of greater trochanter

- ONLY border with NO muscular attachments
- Free rounded edge inferiorly, which blends with the intertrochanteric crest


Lesser trochanter

- Located medially, near the junction of the femoral neck and shaft
- Directed posteromedially


Muscle attachments for lesser trochanter (3)

- Attachment site for iliopsoas muscle (ONLY attachment site for this muscle, which is a major flexor at the hip)
- Psoas major inserts at the apex
- Iliacus inserts at the base of the lesser trochanter, between the spiral and pectineal lines


Intertrochanteric line

- Anterior line
- Located between greater and lesser trochanters at junction of neck and shaft


3 attachments to intertrochanteric line

- Iliofemoral ligament (part of fibrous capsule of hip)
- Vastus lateralis (partial origin)
- Vastus medialis (partial origin)


Intertrochanteric crest

- Located between greater and lesser trochanters
- Hip joint capsule is NOT attached here
- Contains quadrate tubercle


Quadrate tubercle

- Located at mid-intertrochanteric area
- Site of insertion of quadratus femoris
- Sometimes quadrate line is present (instead of tubercle)
- Quadrate tubercle/line extends vertically (straight up) 5 cm with the superior extent located along the intertrochanteric crest


Shaft of femur

3 borders
- Medial
- Lateral
- Posterior

3 surfaces
- Medial
- Lateral
- Anterior


Medial and lateral borders

- Both borders are rough and poorly defined


Posterior border major feature

Linea aspera ("rough line")


Linea aspera

- A crest that is located along the posterior border of the middle 1/3 of femur
- This crest has 2 lips (medial and lateral lips) with a rough area in between (intermediate
- Superiorly, 3 lines joint to form linea aspera


3 lines that join to form linea aspera

- Spiral line
- Pectineal line
- Lateral line


Spiral line

- Medial line from intertrochanter line
- Continuous with linea aspera


Pectineal line

- Intermediate line from lesser trochanter
- Continuous with medial lip


Lateral line

- Lateral line from greater trochanter
- Continuous with lateral lip
- Extends almost vertically
- Gluteal tuberosity is located here for partial insertion of gluteus maximus which also inserts on the IT band


Variation in gluteal tuberosity

- Often times the proximal portion of the gluteal tuberosity is elongated and enlarged
- It is then called the "third trochanter" or "gluteal trochanter"


Inferior landmarks

- Lateral lip and medial lip of linea aspera diverge as 2 ridges into the lateral and medial supracondylar ridges


Lateral supracondylar ridge

- More distinct
- Extends toward lateral epicondyle


Medial supracondylar ridge

- Ends at adductor tubercle
- Smooth, just proximal to adductor hiatus
- Adductor hiatus is where femoral vessels pass to popliteal fossa


Popliteal surface

- The two ridges (lateral and medial supracondylar ridges) form a triangular surface called the popliteal surface


Anterior surface of shaft of femur

- Smooth, convex surface
- Lies between medial and lateral borders
- Attachment site for 2 muscles


2 muscles that attach to anterior surface of shaft of femur

- Vastus intermedius (upper 2/3)
- Articularis genu


Articularis genu

- Femur may be roughened for several small slips of origin for this muscle
- This is the distal attachment (anterior surface of shaft of femur)


Distal extremity of femur

- Major features include medial and lateral femoral condyles


Lateral condyle

- Broader, more pronounced than medial condyle


Medial condyle

- Longer, starts at adductor tubercle


Femoral condyles (general)

- Both condyles articulate with the posterior patella and respective condyles of the tibia
- Both condyles are large, rounded, knob-like structures that project further posterior than anterior


Lateral and medial sulci menisci

- Groove (sulcus) located on each condyle
- This groove separates the patellar and tibial surfaces of the femoral condyles


Lateral sulci menisci

- Completely separates patellar surface of lateral femoral condyle from tibial surface


Medial sulcus menisci

- Deficient laterally (where tibial and patellar surfaces are continuous)


Posterior surface of femur

- Contains intercondylar notch
- Contains intercondylar line


Intercondylar notch

AKA intercondylar fossa
- Separates femoral condyles posteriorly


Intercondylar line

- Serves as posterior boundary of notch
- Forms base of popliteal surface of femur


Attachments to intercondylar line

- ACL attaches posteriorly to the medial surface of the lateral condyle
- PCL attaches anteriorly to lateral surface of medial condyle
- Meniscofemoral ligametns


Medial epicondyle

- Lies above the medial condyle and just below the adductor tubercle
- BOTH the adductor tubercle and medial epicondyle are palpable


Attachments to medial epicondyle and adductor tubercle

- Medial epicondyle is the attachment site for the tibial (medial) collateral ligament
- Adductor tubercle is the attachment site for the tendon of adductor magnus muscle
- Just posterior to the adductor tubercle is the attachment site for the gastrocnemius muscle


Lateral epicondyle

- Also palpable
- Attachment site for fibular (lateral) collateral ligament
- Lower portion has 2 grooves for the popliteus muscle


Popliteus tendon

NOTE - the popliteus tendon changes position based on teh position of the knee (flexed or extended)
- When the knee is FLEXED, the tendon is in the OBLIQUE groove
- When the knee is EXTENDED, the tendon is in the vertical groove

- Flexed = Oblique groove
- Extended = Vertical groove


Femoral arterial supply

- Extensive blood supply for the largest bone in the body
- Proximal, shaft and distal supply


Proximal supply

"FILM O femur"
- F = first perforating artery (enters at neck)
- I = inferior gluteal artery (enters at neck)
- L = lateral femoral circumflex (enters at neck)
- M = medial femoral circumflex (enters at neck)
- O = obturator artery


Medial femoral circumflex artery

- Branch of profunda femoris
- Major supply to femoral head in adults


Obturator artery

- A branch of teh obturator artery courses within the ligament of the head of the femur
- Supplies the femoral head
- Important in infants, children and teens during ossification of the femur
- Unimportant in adults because the medial femoral circumflex is the main supply


Femoral shaft arterial supply

- Nutrient artery from a branch of the second perforating artery
- Nutrient canal is located posteriorly along the upper end of the linea aspera and is directed obliquely upward (away from growing end of bone during development)
- NOTE: for ALL long bones, the nutrient canal is directed obliquely away from growth


Distal femoral arterial supply

- Superior lateral genicular artery
- Superior medial genicular artery
- Descending genicular artery
- Descending branch of lateral femoral circumflex


5 femoral ossification centers

- Primary
- 1st secondary
- 2nd secondary
- 3rd secondary
- 4th secondary


Primary femoral ossification center

- Located at the shaft
- Appears during the 7th fetal week
- Fuses at puberty


1st secondary femoral ossification center

- Located at distal extremity
- Appears around birth
- Fuses at 16-18 years


2nd secondary femoral ossification center

- Located at head
- Appears at 6 months
- Fuses at 17 years


3rd secondary femoral ossification center

- Located at greater trochanter
- Appears at 4 years
- Fuses at 16 years


4th secondary femoral ossification center

- Located at lesser trochanter
- Appears at 12-14 years
- Fuses at 15 years


Notes on ossification

- The femur ossifies via endochondral ossification
- The femur is the first bone to begin this type of ossification
- The femur is the second earliest bone to ossify
- Only the clavicle (which ossifies via an intramembranous method) begins to ossify earlier than the femur
- The appearance and fusion times for each secondary center are inversely related - the later it appears, the sooner it fuses