Biomed 4 Flashcards
Gluteal Muscles - Superficial group
Gluteus maximus, Gluteus medius, Gluteus minimus, Tensor of Fascia Lata
Gluteus Maximus - facts
largest most superficial gluteal muscle, fibres run on 45 degree angle inferiorly, distally attaches indirectly into the tibia (via ITB)
Gluteus Medius - facts
convergent (fan) shaped, deep to glut max, stabilising the pelvis while walking
Gluteus minimus - facts
deep to glute medius, smallest of the gluteal muscles, stabilising the pelvis while walking
Tensor Fascia Lata - facts
enclosed between two layers of fascia lata, gluteal muscle which is located quite anterior, aids stability of knee via iliotibial tract
Gluteal muscles - deep group
externally rotate & stabilise the hip joint
Piriformis, Obturator internus, superior gemellus, inferior gemellus, quadratus femoris
Piriformis - facts
‘pear’ shaped, exits pelvis via greater sciatic foramen, clinically relevant in sciatic neuralgia (piriformis syndrome)
Obturator Internus - facts
exits pelvic cavity through the lesser sciatic foramen
Superior Gemellus & Inferior Gemellus - facts
gemellus (singular), gemelli (plural), superior gemellus is superior to the obturator internus muscle, inferior gemellus is inferior to the obturator internus muscle, gemellus means ‘twin’
Quadratus femoris - facts
short, flat, quadrangular shaped muscle, quadratus = four sided
Anterior thigh muscles - facts (Location, main actions, N/S)
L - span a large area from anterior Lx to bones of leg, cross hip and knee joints, found anterior to femur
A - flex hip joint, extend knee joint
N/S - primarily femoral nerve
Anterior thigh muscles
Pectineus, Iliopsoas (Iliacus, Psoas major, Psoas minor), Sartorius, quadriceps femoris (four headed)
Sartorius - facts
‘tailors muscle’ (produces movements that result in cross legged position), longest muscle in the body
Quadriceps femoris - facts
rectus femoris, vastus lateralis, vastus medialis, vastus intermedius
not separate muscles, four heads
medial thigh muscles - Location, main action, N/S
L - from pubis and ischium to bones of the thigh and leg, found on medial side of femur
A - adduct hip joint
N/S - primarily innervated by obturator nerve
Medial thigh muscles
adductor longus, adductor brevis, adductor magnus, gracilis, obturator externus
Adductor Longus - facts
most anterior muscle of medial thigh group, helps form the borders of the femoral triangle and adductor canal
Adductor brevis - facts
lies deep to pectineus and adductor longus
Adductor magnus - facts
largest, most powerful medial thigh muscle, most posterior in adductor group, two parts (addcutor, hamstring), DA splits to form anatomical space (adductor hiatus)
Adductor Hiatus
opening between distal attachments of adductor magnus & femur, superior to adductor tubercle, allows for passage of femoral artery and vein
Gracilis - facts
most superficial and weakest adductor muscle, only adductor to cross the hip and knee joint
Obturator Externus - facts
passes under the head and neck of the femur, cannot be seen in medial thigh in the lab (too deep)
Posterior thigh muscles - Location, main actions, N/S
L - from pelvis to leg bones, found posterior to the femur
A - extend hip joint, flex knee joint
N/S - tibial or common fibular divisions of the sciatic nerve
Posterior thigh muscles
Semitendinosus, Semimembranosus, Biceps femoris
Semitendinosus
long cord-like tendon which begins about 2/3 of the way down the thigh
Semimembranosus
flat and membranous
Biceps femoris - facts
Two heads:
long head crosses hip & knee joints
short head only crosses knee joint
Regions of Lower Limb
Gluteal
Thigh
Knee region
Leg
Foot
The Pelvis - formed by and function
Bony pelvis formed by - sacrum, coccyx, two hip bones (innominate bones)
Function - protects pelvic organs, is a girdle for the lower limb muscles to attach to & act upon, transfers weight and force between the spine and femurs
Hip Bones - Child
three separate bones (ilium, ischium, pubis)
united by Y-shaped epiphysis at the acetabulum
fuse together by age 20-25
When you put your hands on your hips you are putting then on your …
ilia
when you sit down, you sit on your …
ischium
your pubic bones come together anteriorly at the …
pubic symphysis
Acetabulum
3 parts unite to form large cup-shaped socket
articular surface: femoral head articulates here to form the hip joint
Acetabular notch: incomplete are of the acetabulum inferiorly
Acetabular fossa: depression on the floor of the acetabulum
Sacrum - facts
wedge-shaped/triangular bone
base = superior, apex = inferior
formed by 5 fused sacral vertebrae
transmits weight of body to pelvic girdle
Femur facts
longest, strongest and heaviest bone in body
bone of thigh, transmitting weight from hip to tibia
articulates with innominate at hip
articulates with tibia & patella at knee joint
~ 1/4 of a persons height
Bursa of Gluteal region
Trochanteric bursa - between glute max fibres and greater trochanter
Ischial bursa - between inferior part of glut max and ischial tuberosity
deep fascia of the thigh
fascia lata
deep fascia of the leg
Crural fascia
thickened band of fibres on lateral aspect of fascia lata
iliotibial tract
Inguinal ligament
thickened fibrous band/retinaculum
from ASIS to pubic tubercle
formed by inferior margin of abdominal muscles
hip flexors & neurovascular structures pass beneath to enter/exit thigh
In what position does the gluteus maximus produce the greatest extension force?
from sitting to standing, climbing stairs, squats (on the way up)
Gluteus medius and minimus produce abduction at the hip joint which keeps the pelvis level when in single leg stance. What other movements can gluteus medius and minimus produce?
internal rotation of hip
Why is tensor fascia lata often hard for students to find on a cadaver? Hint it looks white
enclosed between two layers of fascia lata
How does the quadratus/quadriceps femoris get its name? Why should we use the full name of each muscle instead of abbreviating them to ‘quad fem’?
- Quadratus femoris – is a deep gluteal muscle with quadrangular shape
- Quadriceps femoris – is an anterior thigh muscle. Quadriceps stands for 4-headed which describes the four heads (rectus femoris, vastus lateralis, vastus medialis, vastus intermedialis)
Many people refer to the anterior thigh muscles as the ‘quads’. How many muscles are in the anterior thigh that are not part of quadriceps femoris? Name them.
sartorius, pectineus and Iliopsoas (Iliacus, Psoas min & maj)
Which muscle/s pass under the inguinal ligament?
psoas major and iliacus
What is the function of the inguinal ligament in regard to the anterior thigh muscles?
it holds down the muscles like a retinaculum
Where would you expect to find adductor brevis in relation to the other adductor muscles?
Adductor brevis is deep to adductor longus &pectineus and adductor magnus lies deep to adductor brevis
Which part of adductor magnus attaches proximal to the adductor hiatus? Which part attaches distal to the adductor hiatus?
- proximal to the adductor hiatus = Adductor part
- distal to the adductor hiatus = hamstring part
Where does the tendon of obturator externus pass in relation to the femur so that it can attach to the trochanteric fossa?
passes under the head and neck of femur
How do semitendinosus and semimembranosus get their names?
- Semitendinosus has got a long cord-like tendon which begins about 2/3 of the way down the thigh
- Semimembranosus is flat and membranous
Which direction of knee rotation can each of the posterior thigh muscles produce?
- internal rotation = semimembranosus, semitendinosus
- external rotation = biceps femoris
What does the term ‘pes anserine’ mean in Latin?
goose foot
from anterior to posterior, which muscle tendons form the pes anserine?
- Sartorius
- Gracilis
- Semitendinosus
Upon which bone and where on this bone do the pes anserine tendons attach?
superior aspect of medial surface of tibia
How is the hip bone formed in early life?
Y-shaped epiphysis at the acetabulum, fuses together by age 20-25
Male pelvis
deeper, narrower, heavier, thicker
female pelvis
shorter, wider, lighter, thinner
wider pelvis has flow on effect on hip and knee joint angles
Joints of the pelvis
Lumbosacral joint (b/w L5 vertebra & sacrum)
Sacrococcygeal joint (b/w sacrum & coccyx)
Sacroiliac joint (SIJ) (b/w sacrum and ilium)
Pubis symphysis (b/w bilateral pubis bones)
Why is there a limited range of motion of the joints of the pelvis?
It is limited by the interlocking joint surfaces and the strong surrounding ligaments
More designed for weight bearing
Why is the fibrocartilaginous disc of the pubic symphysis wider in females than in males?
Pregnancy, Child-bearing – allows for more movement and stretch
Females pelvis is wider overall
The posterior sacroiliac ligaments are angled in a way that they draw the ilium inwards towards the sacrum as weight pushes down on it. Why might this be so?
to provide stabilisation of SIJ during weight bearing/ when there is a force onto the Ilium
Obturator foramen
formed by ilium and ischium
Enclosed by the obturator membrane, upon which the obturator internus and obturator externus attach proximally
Nutation
Sacral base – tilts anterior & inferior
Apex of sacrum – tilts posterior & superior
Counternutation
Sacral base – tilts posterior & superior
Apex of sacrum – tilts anterior & inferior
Bones of the foot
Tarsals - Calcaneus, Talus, Cuboid, Navicular, 3 Cuneiforms
Metatarsals - 5 metatarsal bones
Phalanges - 14 phalanges
What type of bone are tarsals?
short bones
What type of bones are metatarsals and phalanges?
long bones
Regions of the foot - name all three and which includes which bones.
Hindfoot - talus and calcaneus
Midfoot - navicular, cuboid and three cuneiforms
Forefoot - metatarsals & phalanges
Talus - facts
- only foot bone to articulate with leg bones (tibia, fibula)
- articulates also with calcaneus and navicular
Calcaneus - facts
- transmits weight from talus to ground
- forms heel
- serves as attachment of achiles tendon
Navicular - facts
- boat shaped (means little ship)
- articulates with anterior aspect of talus
- medial side of foot
Cuboid - facts
- cuboidal
- artiuclates with anterior aspect of calcaneus
- lateral side of foot
Cuneiforms - facts
- 3 bones
- medial, 2. intermediate, 3. lateral
- articulate with metatarsals of the same number
Metatarsals - facts
- named 1-5 from medial to lateral
- each has base, shaft and head
- fifth metatarsal has a prominence proximally called the tuberosity/styloid process
Phalanges - facts
- 14, each base, shaft, head
- first digit (great toe, hallux) has two phalanges - proximal & distal
- 2-5 have three phalanges - proximal, middle, distal
- fifth referred as digiti minimi
Sesamoid bones - foot
- 2 sit inferior to head of 1st metatarsal
- preventing crushing the tendon of flexor hallucis longus while standing & walking
Patella - facts
- provides biomechanical advantage to the quadriceps femoris when extending knee
- rounded triangle shape
- muscle attachments (base = DA quadriceps tendon, inferiorly = patellar tendon to tibial tuberosity)
- articulates only with femur
Tibia - facts
- shin bone
- medial, more anterior
- second largest bone in body
- weight-bearing
- transfers weight from femur to talus of foot
Fibula - facts
- lateral, slightly posterior
- no role in weight-bearing
- many muscular attachments
- helps form & stabilise ankle joint
What are the tibia and fibula hold together by?
Strong interosseus membrane as well as superior & inferior tibiofibular joints
Describe the role of fascia in the musculovenous pump
- it assists the musculovenous pump to return the venous blood to the heart
- creating compartmental pressure to return blood back to the heart
Why is the musculovenous pump more important in the lower limb than the upper limb?
it has to work harder against gravity
If a patient came in with compartment syndrome and their neurological and vascular structures within their leg were compressed, what type of symptoms or signs might they present with?
intense pain, tenderness, tightness or burning sensation, numbness/weakness, bruising from trauma, pulselessness, perishingly cold, pale
Movements produced by muscles of leg
plantarflexion
dorsiflexion
eversion
inversion
How many compartments are in the leg and what are they called?
- 4 compartments
Anterior compartment
Lateral compartment
Superficial posterior compartment
Deep posterior compartment
Anterior compartment - facts
Anterior compartment - facts
main actions: dorsiflexor (extensor) compartment
Innervation: deep fibular nerve
Arteries & veins: anterior tibial artery and vein
Which muscles are in the anterior compartment of the leg?
Tibialis anterior, Extensor digitorum longus, Extensor hallucis longus, Fibularis tertius
Lateral compartments - facts
smallest leg compartment
main actions: evert subtalar joint, plantarflex ankle joint
Innervation: Superficial fibular nerve
Arteries & veins: none, supplied by branches of anterior tibial and fibular artery & vein which are located within other compartments
Which muscles are in the lateral compartment of the leg and how can they also be referred as?
Fibularis (peroneus) longus, fibularis (peroneus) brevis
- peroneus/peroneal muscles
Peroneus – the Latin term for fibularis. You will often see this used in texts and many osteopaths will refer to the ‘peroneal muscles’; peroneus longus & brevis instead of fibularis longus & brevis
Posterior compartments - facts
divided into superficial & deep groups by transverse intermuscular septum
main actions: plantarflexion
Innervation: tibial nerve
Arteries & veins: Posterior tibial artery & vein, Fibular artery & vein
These vessels run deep to the transverse intermuscular septum
Which muscles are in the superficial posterior compartment of the leg and what is their main actions?
Plantaris, Gastrocnemius (medial and lateral heads), Soleus
main action: Flex knee joint, Plantarflex ankle joint
Tibialis
related to the tibia
Digitorum – related to the digits
Hallucis – related to the great toe (hallux, digit 1)
Fibularis
related to the fibula
Digitorum
related to the digits
Hallucis
related to the great toe (hallux, digit 1)
What are Retinacula?
thickened bands of deep fascia which hold tendons in place and prevent bow stringing
Extensor retinacula
Two retinacula hold down anterior compartment tendons
- superior extensor retinaculum
- inferior extensor retinaculum
Extensor retinacula - Mnemonic Anterior compartment
from medial to lateral:
Tall Housemates are never dull friends
Tibialis anterior, extensor Hallucis longus, anterior tibial Artery (& vein), deep fibular Nerve, extensor Digitorum longus, Fibularis tertius
Fibular retinacula
two retinacula hold down the tendons of lateral compartment
- superior fibular retinaculum
inferior fibular retinaculum
Flexor Retinaculum
deep posterior compartment
Mnemonic Deep posterior compartment - flexor retinaculum
from anterior to posterior:
Tom Dick And Very Naughty Harry
Tibialis posterior, flexor Digitorum longus, posterior tibial Artery, posterior tibial Vein, tibial Nerve, flexor Hallucis longus
Muscles of the great toe
Abductor hallucis, flexor hallucis brevis, adductor hallucis
Muscles of the 5th digit
Abductor digiti minimi, Flexor digiti minimi brevis
Muscles of Digits 2-5
Flexor digitorum brevis, Quadratus plantae, Lumbricals, Plantar interossei, Dorsal interossei
Muscles on the dorsal surface of the foot
Extensor digitorum Brevis, Extensor Hallucis Brevis
