Bones of the Lower Extremity
Bones of the Pelvic Girdle
• The pelvic (or hip) girdle:
– Attaches the lower limbs to the axial skeleton
– Transmits the weight of the upper body to the
lower limbs
– Supports the visceral organs of the pelvis
– Some of the strongest ligaments of the body
support the pelvic girdle
– Formed by a pair of “hip” bones called coxal
bones, and the sacrum
Each os coxae has an:
• Illium: The large upper portion, often called
your “hip bone”.
• Ishium: The posterior/inferior bone, often
called your “seat bone”.
• Pubis: The anterior/inferior bone, which
connects in front at the pubic symphysis.
• Acetabulum: point of fusion of all three, also
called your “hip socket”.
Landmarks for the Ilium
• Iliac crest: the thick, upper margin
• Iliac fossa: anterior smooth surface
• Anterior superior/ Anterior inferior Iliac spine:
sites for muscle attachments
• Posterior superior/ Posterior inferior Iliac
spine: sites for muscle attachments
• Greater sciatic notch
• Auricular surface
Landmarks for the Ishium:
• Ishial tuberosity: site for attachment of hamstring
muscles
• Ishial spine: site for ligament attachment,
measurement site for pelvic opening.
• Obturator foramen: the only “hole” or opening for
nerves/blood vessels.
• Ishial ramus: point of connection with inferior
ramus of pubis.
Landmarks for the pubis:
• Superior/inferior ramus
• Pubic crest and tubercle: site of attachment for
abdominal muscles
• Pubic symphysis: articulation point that connects
the two pubic bones together
• Pubic arch: helps to determine male vs. female
pelvis
Bones of the Lower Limb
• Femur:
– Single bone of the thigh; is the largest, longest,
and strongest bone in the body.
– The femur cannot be palpated (felt) because it
is covered by large muscles.
– The head of the femur articulates with the
acetabulum of the os coxae, and has a small,
pit shaped depression called the fovea capitis,
which is where the ligamentum teres helps to
secure the head into the acetabulum.
Landmarks of the femur:
•
•
•
•
Head; fovea capitis
Neck: often a site for fracture
Greater and lesser trochanter: attachment site for muscles
Intertrochanteric line and crest: line is anterior, crest is
posterior
• Linea aspera: “rough line” on the posterior aspect of shaft
• Medial and lateral condyle: articulation with the tibia
• Medial and lateral epicondyle: only part of the femur that
can be felt at the knee
• Intercondylar fossa or notch: cruciate ligaments attach here.
• Patellar surface: the smooth surface above the condyles on the
anterior side that articulates with the patella
• Popliteal surface: surface above the condyles on the posterior side
Patella
• The patella is a triangular shaped sesamoid
bone encased in the patellar tendon.
• The patellar tendon attaches the quadriceps
femoris muscle to the tibia.
• It has two surfaces; the rounded, convex
anterior surface, and the smooth, articular
posterior surface.
Tibia
• The bone on the medial side of the lower leg…it is
the weight-bearing bone of the lower leg.
(“Tough Tibia”)
• Landmarks of proximal tibia (upper portion)
– Medial and lateral condyle
• Articulates with the medial and lateral condyle of the femur.
– Intercondylar emminence:
• The ridge of bone that projects upwards between the
condyles. It is the attachment site for the cruciate ligaments,
medial meniscus, and lateral meniscus
– Fibular facet:
• Just below the lateral condyle where the head of the fibula
articulates.
Tibia
• Other Landmarks:
– Tibial tuberosity:
• roughened protuberance on the anterior surface just below
the condyles. Is the attachment site of the patellar ligament.
– Anterior crest
• On the anterior surface of the body. Can palpate the entire
length, also called your “shin”.
– Medial malleolus
• Large bony prominence on the medial side of your ankle
– Fibular notch
• Distal end of tibia, where it articulates with the distal end of
the fibula
Fibula
• The slender bone on the lateral side of the lower
leg. “Fine Fibula”.
• Landmarks:
– Head:
• The enlarged proximal end, articulating with the fibular facet
of the tibia
– Shaft or body:
• Long slender portion
– Lateral malleolus:
• Large prominence on the lateral, distal end. Articulates with
the lateral surface of the talus.
– Malleolar fossa
• Small fossa on the distal end opposite lateral malleolus
Bones of the Foot
• Bones of the ankle are TARSALS
• Bone of the “ball” of your foot are called
METATARSALS… In-between the tarsals and
your toes (phanges).
• Bones of your toes are called Phalanges
(plural). A singular bone is called a phalanx.