Transcript Group 4 Presentation

The Ankle
The ankle joint is formed where the foot and the leg meet. The ankle, or
talocrural joint, is a synovial hinge joint that connects the distal ends of
the tibia and fibula in the lower limb with the proximal end of the talus
bone in the foot.[1] The articulation between the tibia and the talus
bears more weight than between the smaller fibula and the talus.
Movement of the Ankle
The ankle joint is responsible for dorsiflexion
(moving the toes up as when standing only
on the heels) and plantar flexion of the foot
(moving the toes down, as when standing
on the toes), and allows for the greatest
movement of all the joints in the foot. The
ankle does not allow rotation.
-Heaviest and longest bone in the skeleton
-Average length = 18 inches or twice the length of the skull.
-Made up of the shaft and two atricular ends
-Proximal end =head/neck ( ball and socket joint)
-Neck is an oblique offshoot of the shaft that supports head.
-Great Trochanter is at summit of femoral shaft.
-Linea apsera bifurcates both above and below toward the bones end.
- The femur is a long bone whose axis of movement is well outside of
its substance for most of its length. Indeed, the important relationship
of leg anatomy is that a line drawn from the the hip center to the ankle
center passes right through knee center.
1. Greater trochanter
2. Piriformis Fosa
3. Femoral head
4.Fovea of femoral head
5. Femoral Neck
6. Lesser trochanter
7.Intertrochanteric
region
8.Subtrochanteric region
9.Femoral Shaft
10.Supracondylar region
11.Lateral Epicondyle
12.Lateral Condyle of
Femur
13.Trochear groove
14.Medial Condyle of
Femur
15.Medial epicondyle
16.Adductor tubercle
The Foot
-The forefoot includes the five metatarsal bones, and the phalanges
-The first metatarsal bone bears the most weight and plays the most important
role in propulsion. It is the shortest and thickest.It also provides attachment for
several tendons.
-The second, third, and fourth metatarsal bones are the most stable of the
metatarsals. They are well protected and have only minor tendon attachments
and are not subjected to strong pulling forces.
-Near the head of the first metatarsal, on the plantar surface of the foot, are
two sesamoid bones.
-The talus and the calcaneus make up the hindfoot. The calcaneus is the
largest tarsal bone, and forms the heel. The talus rests on top of it, and forms
the pivot of the ankle.
- The sole of the foot from the heel to the base of the big toe measures about
One head length.
Foot and Toe movement
-Toe movements take place at the joints. These joints are capable of motion
in two directions: plantar flexion or dorsiflexion. In addition, the joints permit
abduction and adduction of the toes. The foot as a whole (excluding the toes)
has two movements: invertion and evertion. All the joints of the hindfoot and
midfoot from the subtalar contribute to these movements, which are complex
and consist of several components.In addition,foot movements ordinarily are
combined with ankle movements.
Plantar: Pertaining to the sole of the foot.
Plantar Fascia: The tight band of muscle beneath the arch of the foot.
Plantar Fasciaitis: Inflammation of the plantar fascia; associated with
overuse of acute foot injury.
Plantarflexion: Ankle motion such that the toes are pointed toward the ground.
Pronation: In the foot, it is a combination of motions resulting in a position
such that the foot is abducted and everted. Foot pronation can be a by-product
of an arch problem, leg length discrepancy, or chronically bad running
mechanics; can be compromised with the use of an orthotic. In the hand,
pronation is movement of the forearm into a palm down position.
The Arches
The foot has two important functions: weight bearing and propulsion. These
functions require a high degree of stability. In addition, the foot must be flexible,
so it can adapt to uneven surfaces. The multiple bones and joints of the foot
give it flexibility, but these multiple bones must form an arch to support any
weight.
The foot has three arches. The medial longitudinal arch is the highest and most
important of the three arches. It is composed of the calcaneus, talus, navicular,
cuneiforms, and the first three metatarsals. The lateral longitudinal arch is lower
and flatter than the medial arch. It is composed of the calcaneus, cuboid, and
the fourth and fifth metatarsals. The transverse arch is composed of the
cuneiforms, the cuboid, and the five metatarsal bases.
The arches of the foot are maintained not only by the shapes of the bones as
well as by ligaments. In addition, muscles and tendons play an important role in
supporting the arches.
Muscles and Bones
26 bones (One-quarter of the bones in the human body are in the feet.);
33 joints;
more than 100 muscles, tendons (fibrous tissues that connect muscles to bones),
and ligaments (fibrous tissues that connect bones to other bones); and
a network of blood vessels, nerves, skin, and soft tissue.
There are 20 muscles in the foot that give the foot its shape by holding the
bones in position and expand and contract to impart movement.
The main muscles of the foot are: the anterior tibial, which enables the foot
to move upward; the posterior tibial, which supports the arch;
the peroneal tibial, which controls movement on the outside of the ankle;
the extensors, which help the ankle raise the toes to initiate the act
of stepping forward; and the flexors,
which help stabilize the toes against the ground
The Tibia
• The shinbone
• Takes part in the joint
of the knee
• Composed of 3 parts
– The Proximal end
– The shaft
– The Distal End
Proximal End
• The head of the tibia
• Supports the weight of the
femur
• Parts;
–
–
–
–
–
Intercondylar eminence
Medial condyle
Lateral condyle
Articular surfaces
Tuberosity of the tibia
The Shaft
• Contains a double curve
• Triangular in its cross
sections of curves
• Parts;
–
–
–
–
The posterior surface
Interosseous crest
Medial Margin
Anterior Crest
• Rises from the tuberosity
• Divides front of tibia into
lateral and medial
surfaces
• Known as the shin
The Distal End
• Four sided
• Flat front and back
surfaces
• Parts;
– Fibular notch
• Receives the fibula
– Medial Malleolus
• Extension of the medial
surface
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
The Fibula
• Corresponding height
to Tibia
• Dropped below the
Tibia to fit into the
Medial Malleolus
• Parts
– Proximal End
– Shaft
– Distal End
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Proximal End
• The Head of the
Fibula
• Joins the lateral
surface of the head of
the tibia to the rear
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
The Shaft
• Triangular in cross section
• Narrow, Consistent in width
• Four Borders
–
–
–
–
The Antero-external
The Antero-internal
The postero-external
The postero-internal
• Four surfaces
–
–
–
–
The anterior surface
The external surface
The internal surface
The posterior surface
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Distal End
• Resembles the head in size,
but is more flattened
• Fits into the fibular notch of
tibia (the nose)
• Parts;
– Lateral Malleolus
• Corresponding part to tibial
medial malleolus
• Drops below the tibia to fit
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.