Lower Limb Flashcards
What are the key functions of the upper and lower limbs respectively
Upper: designed to place and use the hand in as many positions as possible so requires more mobility than stability at its joints
Lower: requires greater stability in order to bear weight
Give 4 major differences between upper and lower limbs
Rotation
Pelvic girdle is fixed whereas pectoral girdle is mobile
Tibia and fibula are fixed whereas radius and ulnar have movement between them
Hand has substantial independent digital movement (especially the thumb) whereas the foot is adapted to act as a segmented arched structure with limited independent movement of toes
5 roles of the vertebral column
Protect spinal cord and nerves
Support weight of body above pelvis
Provide a rigid and flexible axis for body and pivot for head
Posture and locomotion
Shock absorber
Describe the primary curves of the spine (2)
Found in embryonic life and are concave anteriorly (kyphosis)
Present in thoracic and sacral regions
Describe the secondary curves of the spine
Develop after birth and is concave posteriorly (lordosis)
Present in cervical region and lumbar region
Why do we have lordosis in the cervical spine ?
What kind of curve is this
To support the head and for binocular vision
Secondary
What is the point of the body and neural arch of a vertebral body
Body- weight bearing
Arch- protection
What is the neural arch made of
Pericles joining it to the body and lamina connecting the pedicles posteriorly
Where are the articular facets in the vertebral body
What kind of joint exists here
At the junction of the transverse processes: 2 superior and 2 inferior
Synovial
Where is the intervertebral foramen
Why do we have this
Formed between the pedicles of adjacent vertebrae
Where spinal nerves pass through
How are adjacent vertebrae connected
What kind of joint is this
By intervertebral discs and 2 ligaments connecting the vertebral bodies
Secondary cartilaginous
What is a vertebral disc composed of
A central nucleus pulposus which becomes more solid with age
This is surrounded by concentric rings of fibrocartiledge (the annulus fibrosis)
What is the nucleus pulposus a remnant of
What is it like at birth
The notochord
The nucleus pulposus is fluid at birth
What is the point of the annulus fibrosis
Resists torsion movements between vertebral bodies
What are the ligaments called that connect the vertebral bodies
Anterior and posterior longitudinal ligaments
What is a prolapsed disc and where does it usually occur
Degeneration and rupture if the annulus fibrosis, leading to protrusion of the nucleus pulposus which may press on a spinal nerve or the spinal cord
Most commonly happens in the lower lumbar region
Where are ligaments connected to the vertebrae to strength the facet joints
Give the name of each ligament
Spinous processes (supraspinous and infraspinous) Transverse processes (intertransverse) Laminae (ligamentum flavum)
Where is the human centre of gravity
~55% of the person’s height above the ground
Usually 3cm in front of the 2nd sacral vertebra
What are the movement tendencies for all lower limb joints
Extension
What are the tendencies of the cervical, thoracic and lumbar regions of the spine
Cervical- flexion
Thoracic- flexion
Lumbar - extension
What resists cervical tendency
Tendency is flexion
Erector spinae and ligamentum nuchae resist this
What resists thoracic tendency
Tendency is flexion
Resisted by erector spinae
What resists lumbar extension
There is little muscle action needed
What resists hip joint tendency
Tendency is extension
Resisted by tension in iliofemoral ligament