Functional Anatomy Week 2 - muscles, hip and femur bones, muscles and ligaments Flashcards
What do muscles do
Produce movement
Maintain postures and positions
Protection
Driving circulatory system (vascular pump)
3 different types of muscle
Smooth
Cardiac
Skeletal
What types of muscles contract involuntarily
Smooth and cardiac muscles
What types of muscles contract voluntarily
Skeletal muscles
What was the early prediction about how a muscle contracts?
‘Animal spirit’ flowed from the head to the muscles and that the volume of a muscle increases when contracting
The baloonist theory
Attempted to explain muscle movement by asserting that muscles cotract by inflating with air or flud.
Debunking of the balloonist theory
Jan Swammerdam placed a frog thigh muscle in an airtight syringe with water in the tip, therefore he could determine whether there was a change in volume of the muscle when it contracted by observing a change in the level of water
When JS caused muscle to contract by irritating nerve, the water level didnt rise but was lowered –> no air/fluid could be flowing into the muscle hence the balloonist theory was wrong
Aponeurosis
A sheet where 2 groups of muscle fibres converge
Muscle fibre architecture
If fibres are parallel to axis of muscle = parallel
If fibres cross over axis = bipennate, unipennate, multipennate
Location of the ilium
The large, curved bone, superior of the pelvis
What is the PCSA
Physiological cross-sectional area
The area of the cross section of a muscle perpendicular to its fibres
Diffferences between penate muscles and parallel muscles
Penate muscles are stronger as more fibres are packed - they have greater PCSA
However, penate muscles are slower as its fibres have to shorten over a greater distance than parallel muscles
Muscles consist of
Bundles of muscle fascicles
Each fascicles is a bundle of muscle fibres
Each fibre is a bundle of myofibrils
Myofibrils are sarcomeres connected in series
Location of the pubis
At the anterior of the pelvis
What are the 2 parts of the pubis
The superior and inferior pubic rami
Location of the ischium
Posterior inferior aspect of the pelvis
Parts of the ilium
Iliac crest
Anterior superior iliac spine (ASIS)
Posterior superior iliac spine (PSIS)
What is the part of the body that we sit on called
Ischial tuberosity
Parts of the femur
Head
Neck
Shaft
Greater trochanter - lateral side
Lesser trochanter - medial side
Adductor tubercle - where some of the adductor muscles attatch onto
Medial femoral condyle
Lateral femoral condyle
Where does the femur connect to the hip
What surrounds it
Acetabulum - made up of all 3 of the ischium, ilium and pubis
Lunate surface of the acetabulum surrounds it
Difference between a male and female pelvis
Males have higher iliac crests
Pelvic inlet is more heart shape on a male. It is more round on a female
Angle between the two inferior pubic rami on a male is much smaller
Where is the synovial membrane on the femur located
What does it do
Surrounds the head of the femur
Secretes synovial fluid into the joint
A soft tissue of the hip joint attached to the acetabular rim
What is its job
The acetabular labrum
Extends the socket out to hold the femur more tightly into the joint
A structure more superficial to the synovial membrane and surrounds the head and neck of the femur
The joint capsule
What are ligaments inside/outside the joint capsule called
Intra/Extra-capsular ligaments
3 extra-capsular ligaments
iliofemoral, pubofemoral, ischiofemoral
they loosen during flexion (provides more stability during extension which is necessary for standing up)
Location, origin and insertion of the inguinal liagament
Runs anteriorally along the front of the pelvis
Origin is the ASIS and inserts into the pubis
What are the main bursae located at the hip called
What does it do
Iliopectineal bursa - located anterior to the hip joint capsule
Trochanteric bursa - located on greater trochanter
Reduce friction where tendons, muscles, soft tissue cross over one another
2 intracapsular ligaments and their locations
Transverse acetabular ligament - sits between the 2 ends of the lunate surface of the acetabulum
Ligamentum teres - located in the centre of the acetabulum and connects into the dimple on the head of the femur. Holds head of femur in place. Has a blood supply which supplies blood into femur
What are the hip flexors
iliacus, psoas major, pectineus, rectus femoris, sartorius
What are the hip extensors
Biceps femoris, semimembranosus, semitendinosus, gluteus maximus
Origin and insertion of the iliacus
Medial aspect of the iliac crest –> lesser trochanter of femur
Origin and insertion of the psoas major
Vertebral bodies of T12 and L4 –> lesser trochanter of femur
Origin and insertion of the pectineus
Superior rami of the pubis –> pectineal line
Origin and insertion of the rectus femoris
ASIS –> tendon at the top of the patella, before this attatches to below the knee, inserts onto tibial tuberosity
Origin and insertion of the sartorius
ASIS –> anterior medial side of the tibia
Innervation of the hip flexors
Femoral nerve
Psoas major NOT included - inervated by nerves in the vertebrae
Origin and insertion of the long head of the biceps femoris
Ischial tuberosity –> lateral aspect of head of fibula
Origin and insertion of the semitendinosus
Ischial tuberosity –> proximal end of tibia below medial condyle
Origin and insertion of the semimembranosus
Ischial tuberosity –> medial condyle of the tibia
Origin and insertion of the gluteus maximus
Iliac crest, sacrum and coccyx –> femur and ilioibial band
Innervation of the hip extensors
Glut max - inferior gluteal nerve
Hamstrings - sciatic nerve
What are the hip abductor muscles
Gluetus minimus, gluteus medias, gluteus maximus, tensor fascia latae
Origin and insertion of the gluteus minimums
ilium –> greater trochanter of femur
Origin and insertion of the gluteus medias
ilium –> greater trochanter of femur
Origin and insertion of the tensor fascia latae
ilium –> iliotibial band
Innervation of the hip abductors
glut max - inferior gluteal nerve
glut med + min, TFL –> superior gluteal nerve
What are the hip adductors
Adductor magnus, adductor longus, adductor brevis, pectineus and gracilis
Origin and insertion of Adductor magnus
Pubic ramus, ischial ramus –> linear aspera
Origin and insertion of Adductor brevis
Pubis –> linear aspera
Origin and insertion of Adductor longus
Pubis –> linear aspera
Origin and insertion of pectineus
pectineal line of pubis –> pectineal line of femur
Origin and insertion of gracilis
Inferior pubic rami –> medial tibia at the pes anserinus
Innervation of the hip adductor muscles
Obturator and sciatic nerve
What are the hip internal rotators
Gluteus minimus, gluteus medius and tensor fascia latae
What are the hip external rotators
Obturator internus and externus, Gemellus inferior and superior, quadratus femoris, piriformis and gluteus maximus
Origin and insertion of the obturator internus and externus
Internus = obturator membrane –> greater trochanter
Externus = obtutator membrane –> greater trochanter
Origin and insertion of the superior and inferior gemellus muscle
Superior = ischium –> greater trochanter
Inferior = ischium –> greater trochanter
Origin and insertion of the quadratus femoris
Ischial tuberosity –> Intertrochanteric crest of femur
Origin and insertion of the piriformis
Anterior aspect of sacrum –> greater trochater