Femur
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Transcript of Femur
Prepared by
Dr.hawre dlzar
Forensic doctor and anthropologist
Anatomy:
The femur is the longest, heaviest, and strongest bone in the
body. It supports all of the body’s weight during standing,
walking, and running. Because of its strength and density, it is
frequently recovered in forensic, archaeological, and
paleontological contexts. The femur is a particularly valuable
bone because of the information it can provide on the stature of
an individual
The femur articulates with the acetabulum of the os coxae.
Distally, it articulates with the patella and the proximal tibia.
The leg’s actions at the hip include medial and lateral rotation,
abduction, adduction, flexion, and extension. At the knee,
motion is far more restricted, confined mostly to flexion and
extension. Although the main knee action is that of a sliding
hinge, this joint is one of the most complex in the body.
a. The femoral head is the rounded proximal part of the bone
that fits into the acetabulum.
It constitutes more of a sphere than the hemispherical humeral
head.
b. The fovea capitis is the small, nonarticular depression near
the center of the head of the femur. It receives the ligamentum
teres from the acetabular notch of the os coxae.
c. The femoral neck connects the femoral head with the shaft
and the greater trochanter.
d. The greater trochanter is the large, blunt, nonarticular
prominence on the lateral, proxi- mal part of the femur. It is
the insertion site for the gluteus minimus (anterior aspect of the
trochanter) and gluteus medius muscles (posterior aspect), both
major abductors of the thigh and stabilizers of the hip. Their
origins are on the broad, iliac blade of the os coxae.
These muscles are crucial in stabilizing the trunk when one leg
is lifted from the ground
during bipedal locomotion.
The lesser trochanter is the blunt, prominent tubercle on the
posterior femoral surface
just inferior to the point where the neck joins the shaft. This is
the point of insertion of
the iliopsoas tendon (the common tendon of the iliacus muscle,
originating in the iliac fossa,
and the psoas major muscle, originating from the lumbar
vertebrae and their disks). These
muscles are major flexors of the thigh at the hip.
spiral line, spiraling inferior to the lesser trochanter, connects the inferior end of the
intertrochanteric line with the medial lip of the linea aspera. It is the origin of the vastus
medialis muscle, a part of the quadriceps femoris muscle, a knee extensor that inserts on the anterior tibia via the patella.
The pectineal line is a short, curved line that passes inferolaterally from the base of the lesser trochanter, between the spiral line and gluteal tuberosity. It is the insertion of the pectineus muscle, which originates from the pubic part of the os coxae and acts to adduct,
laterally rotate, and flex the thigh at the hip.
femoral shaft is the long section between the expanded proximal and distal ends of the bone.
medial condyle is the large, articular knob on the medial side of
the distal femur. Its medial surface bulges away from the axis of
the shaft. The medial condyle extends more distally than the
lateral condyle.
medial epicondyle is the convexity on the medial side of the
medial condyle. It is a point of attachment for the medial
collateral ligament of the knee.
Landmarks
• head
• shaft
• greater trochanter
• femoral tubercle
• adductor tubercle
• medial epicondyle
• medial condyle
• trochanteric fossa
• gluteal tuberosity
• intercondylar fossa
• neck
• fovea capitis
• lesser trochanter
• intertrochanteric crest
• quadrate tubercle
• lateral epicondyle
• lateral condyle
pectineal line
• linea aspera
• intercondylar line
The femur ossifies from five centers: the shaft, the femoral head,
the distal end, the greater tro- chanter, and the lesser trochanter.
The femoral head appears at about 6 months to a year. It begins to
fuse to the diaphysis at 14 –19 years in males, and at about 12–
16 years in females. The greater trochanteric epiphysis appears
between ages 2–5. It then begins to fuse at 16 –18 years in
males, and at 14 –16 years in females. The lesser trochanteric
epiphysis appears between ages 7–12 and then begins to fuse at
16 –17 years in both sexes. The distal epiphysis appears just
before birth. It begins to fuse with the shaft at about 16 – 20 years
in males, and at about 14 – 18 years in females (Scheuer and
Black, 2000).
Neither intact femora nor femoral fragments are easily confused
with other bones.
The femoral head has a fovea and is a more complete sphere than
the humeral head.
The femoral shaft is larger, has a thicker cortex, and is rounder in
cross section than any •
other shaft. It has only one longitudinal feature with sharp edges,
the linea aspera
• For intact femora or proximal ends, the head is proximal and faces medially. The lesser
trochanter and linea aspera are posterior.
• For isolated femoral heads, the fovea is medial and displaced posteriorly and inferiorly.
The posterior inferior head–neck junction is more deeply excavated than the anterosuperior
junction.
• For proximal femoral shafts, the nutrient foramen opens distally, and the linea aspera is
posterior and thins inferiorly. The gluteal tuberosity is superior and faces posterolaterally.
• For femoral midshafts, the nutrient foramen opens distally, the bone widens distally, and
the lateral posterior surface is usually more concave than the medial posterior surface.
• For distal femoral shafts, the shaft widens distally and the lateral supracondylar ridge is
more prominent than the medial. The medial condyle extends more distally than the lateral.
• For femoral distal ends, the intercondylar notch is posterior and distal, and the lateral bor-
der of the patellar notch is more elevated. The lateral condyle bears the popliteal groove, and
the medial condyle bulges away from the line of the shaft. Relative to the shaft axis, the
lateral condyle extends more posteriorly than the medial. The medial condyle extends more
distally than the lateral because in anatomical position the femur angles beneath the body.
1-Maximum femoral length (Martin, 1928: 1037, #1; Buikstra
and Ubelaker, 1994: 82,
#60): The maximum length that can be measured between the top
of the femoral head and the bottom of the farthest condyle.
Measured with an osteometric board.
2-Femoral biomechanical length (Trinkaus et al., 1999: 757): Using a large sliding cali- per, place the stationary jaw on the inferiormost point of the superior femoral neck, and then measure the distances to: 1) the distalmost point of the medial condyle; and 2) the distalmost point of the lateral condyle. Biomechanical length is the average of these two distances.
3. Femoral bicondylar (or physiological) length (Martin, 1928: 1037–1037, #2; Buikstra and Ubelaker, 1994: 82, #61): Place both condyles firmly against the stationary end of an osteometric board and, while keeping the shaft of the femur parallel to the surface of the board, measure the distance to the furthest point on the femoral head.
4. Femoral midshaft circumference (Martin, 1928: 1040, #8; Buikstra and Ubelaker,
1994: 83, #68): Determine the location of midshaft (preferably using 50% of femoral biomechanical length) and use a flexible cloth tape to determine the minimum circum- ference at that location.
5. Femoral epicondylar breadth (Martin, 1928: 1041, #21; Buikstra and Ubelaker, 1994:
82, #62): With a sliding caliper or an osteometric board, measure the distance between the medialmost and lateralmost points on the epicondyles.
6. Femoral torsion (Martin, 1928: 1043, #28): Place the femur posterior-side-down on a flat table so that it rests stably on three points: the posteriormost points of each condyle and the posteriormost point of the greater trochanter. Using a goniometer or protractor, measure the angle formed between the longitudinal axis of the femoral neck (and head) and the table.
7. Femoral anteroposterior (or sagittal) midshaft diameter (Martin, 1928: 1039: #6; Buikstra and Ubelaker, 1994: 83, #66): Determine the location of midshaft (preferably
50% of femoral biomechanical length) and use a sliding caliper to determine the antero- posterior dimension at that point (including the linea aspera).
NECROSIS OF THE FEMORAL HEAD
Pathology
Subcapital or transcervical fracture of the neck of the
femur frequently is complicated by aseptic necrosis of part
or all of the femoral head .This is due to the
peculiarity of the blood supply to the femoral head, which
consists of three groups of vessels: (1) the artery of the ligamentum teres, which supplies approximately the medial
third of the head surrounding the fovea (2)the inferior
metaphyseal vessels coursing beneath the synovium on the
inferior aspect of the femoral neck, which supplies the
inferior portion of the head; and (3)the lateral epiphyseal
vessels, which enter the head within 1 cm distal to the
margin of the articular cartilage.
Pathology:
Legg-Calvr-Perthes disease has a clear relationship
with disrupted blood supply that is probably initiated by
trauma. It is associated with extensive aseptic necrosis of
the epiphysis of the femoral head. It is an uncommon
disease, occurring unilaterally in 90% of cases. It usually
begins between 5 and 9 years of age, and is much more
common in boys than girls (Jaffe 1972:566; Resnick
1995g:3561).
Human_Osteology__Third_Edition.
human osteology and skeletal radiology.
Human Anatomy2012.