Download TIBIA BONE Learning objectives

TIBIA BONE
Learning objectives:
At the end of the lecture, the student should be able to describe:
 The division of tibia bone in 3 parts
 The surfaces and borders of tibia
 The attachments of muscles on the tibia bone
 The ossification of tibia and its primary and secondary ossification
centers
Lecture outline:
Tibia:
 Prismoid in form, expanded above, where it enters into the
knee-joint, contracted in the lower third, and again enlarged but to a
lesser extent below.
 In the male, its direction is vertical, and parallel with the bone
of the opposite side , in the female it has a slightly oblique
direction downward and lateralwards, to compensate for the
greater obliquity of the femur.
 It has a body and two extremities/ ends (upper & lower).
The upper extremity:
 The upper extremity is large
 Expanded into two eminences, the medial
and lateral condyles.
 The superior articular surface presents
two smooth articular facets .
The medial facet :
 oval in shape
 slightly concave from side to side, and from before backward .
The lateral facet :
 nearly circular
 is concave from side to side, but
slightly convex from before
backward, especially at its posterior
part, where it is prolonged on to the
posterior surface for a short
distance .
The central portions of these facets articulate with the condyles of the
femur, while their peripheral portions support the menisci of the knee-joint.
Intercondyloid eminence (spine of tibia):
 Located between the articular facets
 It is surmounted on either side by a prominent tubercle, on to the sides
of which the articular facets are prolonged
 In front of and behind are rough depressions for the attachment of the
anterior and posterior cruciate ligaments and the menisci.
Anterior surfaces of condyles:
 Continuous with one another
 Forms a large flattened triangular area which is broad above, and
perforated by large vascular foramina; narrow below where it ends in
tuberosity of the tibia
Tuberosity of the tibia :
 A large oblong elevation.
 Gives attachment to the ligamentum patellae
 A bursa intervenes between the deep surface of the ligament and the
part of the bone immediately above the tuberosity.
Posterior surfaces of condyles:
 Posteriorly , condyles are separated from each other by a shallow
depression, the posterior intercondyloid fossa.
 This fossa gives attachment to part of the posterior cruciate ligament
of the knee-joint.
 The medial condyle has a deep transverse groove posteriorly for the
insertion of the tendon of the Semimembranosus.
 Its medial surface is convex, rough, and prominent and gives
attachment to the tibial collateral ligament.
The lateral condyle :
 Posteriorly, it has a flat articular facet, circular in form which is
directed downward, backward, and lateralward for articulation with
the head of the fibula.
 Lateral surface is convex, rough, and prominent in front
 Has got an eminence, situated on a level with the upper border of the
tuberosity and at the junction of its anterior and lateral surfaces, for
the attachment of the iliotibial band.
 Just below this a part of the Extensor digitorum longus takes origin
and a slip from the tendon of the Biceps femoris is inserted.
Body of tibia:
Has three borders and three
surfaces.
Borders :
Anterior
Medial
Interosseous
The anterior crest or border :
 The most prominent of the three
 Commences above at the
tuberosity
 Ends below at the anterior margin of the medial malleolus.
 Is sinuous and prominent in the upper two-thirds of its extent, but
smooth and rounded below
 Gives attachment to the deep fascia of the leg.
Surfaces:
Lateral
Medial
Posterior
Lateral surface:
 Narrower than the medial one
 Upper two-thirds present a shallow groove for the origin of the Tibialis
anterior
 Lower third is smooth, convex, curves gradually forward to the
anterior aspect of the bone
 Is covered by the tendons of the Tibialis anterior, Extensor hallucis
longus, and Extensor digitorum longus from medial to lateral side
Posterior surface:
 Has a prominent ridge in its upper part, the
popliteal line,
 This line extends obliquely downward from the
back part of the articular facet for the fibula to
the medial border, at the junction of its upper
and middle thirds
Attachments:
 Marks the lower limit of the insertion of
the Popliteus
 Serves for the attachment of the fascia
covering this muscle
 Gives origin to part of the Soleus, Flexor
digitorum longus, and Tibialis posterior.
 The triangular area, above this line, gives
insertion to the Popliteus.
 The middle third of the posterior surface
is divided by a vertical ridge into two
parts; the ridge begins at the popliteal
line and is well-marked above, but
indistinct below; the medial and broader portion gives origin to the
Flexor digitorum longus, the lateral and narrower to part of the
Tibialis posterior.
 The remaining part of the posterior surface is smooth and covered by
the Tibialis posterior, Flexor digitorum longus, and Flexor hallucis
longus.
 Immediately below the popliteal line is the nutrient foramen, which is
large and directed obliquely downward.
The lower extremity
 The lower extremity, much smaller than the upper, presents five
surfaces
 It is prolonged downward on its medial side as a strong process, the
medial malleolus.
Surfaces:
The inferior articular surface
 Is quadrilateral, and smooth for articulation with the talus.
 It is concave from before backward, broader in front than behind, and
traversed from before backward by a slight elevation, separating two
depressions.
 Is continuous with that on the medial malleolus.
The anterior articular surface
 Is smooth and rounded above
 Covered by the tendons of the
Extensor muscles
 Lower margin presents a
rough transverse depression
for the attachment of the
articular capsule of the anklejoint.
The posterior articular surface
 Is traversed by a shallow
groove directed obliquely
downward and medialward,
 It is continuous with a similar
groove on the posterior
surface of the talus and
serving for the passage of the
tendon of the Flexor hallucis
longus.
The Lateral articular surface
 Presents a triangular rough depression for the attachment of the
inferior interosseous ligament connecting it with the fibula
 The lower part of this depression is smooth, covered with cartilage in
the fresh state, and articulates with the fibula.
 The surface is bounded by two prominent borders, continuous above
with the interosseous crest
 They afford attachment to the anterior and posterior ligaments of the
lateral malleolus.
The Medial articular surface
 Is prolonged downward to form a strong pyramidal
process, flattened from without inward—the medial
malleolus.
 The medial surface of this process is convex and
subcutaneous
 Its lateral or articular surface is smooth and slightly
concave, and articulates with the talus
 Its anterior border is rough, for the attachment of
the anterior fibers of the deltoid ligament of the
ankle-joint
 Its posterior border presents a broad groove, the
malleolar sulcus, directed obliquely downward and
medialward, and occasionally double
 This sulcus lodges the tendons of the Tibialis
posterior and Flexor digitorum longus.
 The summit of the medial malleolus is marked by a
rough depression behind, for the attachment of the
deltoid ligament.
Muscular attachments on tibia
Ossification of tibia
 The tibia is ossified from three centers one for the body and one for
either extremity.
 Ossification begins in the center of the body, about the seventh week of
fetal life, and gradually extends toward the extremities.
 The center for the upper epiphysis appears before or shortly after
birth; it is flattened in form, and has a thin tongue-shaped process in
front, which forms the tuberosity;
 The center for the lower epiphysis appears in the second year.
 The lower epiphysis joins the body at about the eighteenth, and the
upper one joins about the twentieth year.
 Two additional centers occasionally exist, one for the tongue-shaped
process of the upper epiphysis, which forms the tuberosity, and one for
the medial malleolus.
Fractures of tibia bone
The Gosselin fracture is a V-shaped fracture of the distal tibia which extends into the
ankle joint and fractures the tibia into anterior and posterior fragments
A Bumper fracture is a fracture of the lateral tibial plateau caused by a forced valgus
applied to the knee. This causes the lateral part of the distal femur and the lateral tibial
plateau to come into contact, compressing the tibial plateau and causing the tibia to
fracture.
Pott's fracture also known as Pott’s syndrome and Dupuytren fracture, The injury is
caused by a combined abduction external rotation from an eversion force. This action
pulls on the extremely strong medial (deltoid) ligament, often tearing off the medial
malleolus.
The combined fracture of the medial malleolus, lateral malleolus, and the posterior
margin of the distal end of the tibia is known
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