anatomy dissection 2 Flashcards
what type of joint is the knee joint ?
it is a synovial hinge joint
what are the 3 articulations of the knee joint ? and which bone does not take part in the knee joint ?
3 articulations in total; 2 between the femur and the tibia, 1 between the femur and the patella the fibula does not take part in the knee joint
what are the main movements of the knee joint ?
flexion and extension
what muscles cause extension of the knee and what are they supplied by ?
quadriceps supplied by the femoral nerve
what muscles cause flexion of the knee and what are these muscles supplied by ?
mainly hamstrings & gastrocnemius
supplied by tibial and common fibular nerve
when the knee is flexed what is achievable
a degree of medial & lateral rotation is achievable
which muscles control the lateral rotation of the knee and what are they supplied by ?
biceps femoris
supplied by the tibial and common fibular nerve
which muscles control medial rotation of the knee and what are they supplied by ?
hamstrings & gracilis
supplied by the obturator nerves
what encloses the synovial cavity of the knee joint ?
a fibrous capsule which attaches round the margins of the articular cartilage
what the ligaments of the knee which help to strengthen the fibrous capsule and stabilise the knee ?
are the iliotibial tract, the tibial (medial) and fibular (lateral) collateral ligaments and the cruciate ligaments (anterior and posterior).
what is the function of the medial and lateral menisci ?
act as shock absorbers as well as assisting with stabilisation of the curved femoral condyles upon the relatively flatter tibial condyles.
give some examples of common abnormalities in knee alingments
Genu varum (“bandy legs” or “bow legs”) and genu valgam (“knock knees”)
what may predispose to abnormalities such as Genu varum (“bandy legs” or “bow legs”) and genu valgam (“knock knees”)
associated with loss of the medial or lateral meniscus respectively.
where are the menisci thicker ?
where they are attached peripherally to the fibrous capsule
what makes the medial menisci more vulnerable to a tearing near injury ?
The medial meniscus is also attached peripherally to the tibial (medial) collateral ligament which makes it more vulnerable to tearing in a knee injury.
describe what is meant by an unhappy triad knee injury?
Such an injury could occur after a blow to the lateral side of the knee that distracts and twists the medial aspect of the joint. If the injury is such that the ACL is also ruptured, it is referred to as an “unhappy triad” knee injury.
what are both menisci anchored too ?
anchored anteriorly and posteriorly by attachment to the tibial intercondylar area
what are the cruciate ligaments named according too ?
according to their site of attachment to the intercondylar eminence of the tibia. They both attach between tibia and femur
explain the route of the ACL
(ACL) passes superiorly, laterally and posteriorly to attach to the lateral femoral condyle.
what specifically does the ACL do ?
(ACL) passes superiorly, laterally and posteriorly to attach to the lateral femoral condyle.
what test asesses the integrity of the ACL?
anterior drawer test assesses the integrity of the ACL
describe the route of the PCL
(PCL) lies medial to the ACL and passes superiorly and anteriorly to attach to the medial femoral condyle.
what does the PCL do ?
prevents posterior displacement of the tibia on the femur and helps prevent hyperflexion of the joint.
what test asesses the PCL ?
integrity of this ligament is tested by the “posterior drawer” test.
what is the suprapatellar bursa?
is an extension of the synovial cavity.
what does the presence of the suprapatellar bursa do?
reduces friction on the quadriceps tendon during knee movements
what can abnormal fluid within the knee joint e.g. blood, inflammator exudate or pus cause?
what test can be used to detect this accumulation of abnormal fluid?
can fill the suprapatellar bursa causing a swelling visible in the lower third of the anterior thigh.
massage test
how does the common fibular nerve enter the anterior compartment of the leg ? and what is it vulnerable too?
from the popliteal fossa superficial to the neck of the fibula
it is vulnerable to injury (e.g. compression injury from tight below knee POP - type of cast).
where does the common fibular nerve divide and what into?
divides at the neck fo the fibula - into the superficial and deep fibular nerve
what does the superficial fibular nerve supply ?
the muscle of the lateral compartment of the leg and the skin/fascia of the dorsum of the foot
what does the deep fibular nerve supply ?
supplies the muscles of the anterior compartment of the leg and the skin of the first interdigital cleft.
what do all the muscles of the anterior compartment of the leg attach too ?
All muscles of the anterior leg attach proximally to tibia, fibula or interosseous membrane
what do all the muscles of the anterior compartment of the leg attach distally too?
to the base of 1st metatarsal and medial cuneiform (Tibialis Anterior), distal phalanges of great toe (Extensor Hallucis Longus) and all digits (Extensor Digitorum Longus) and base of 5th metatarsal (Fibularis Tertius).
what are the main actions of the foot ?
dorsiflexion of the ankle, great toe and digits and inversion and eversion
what muscles cause inversion of the foot ?
Tibialis Anterior – in combination with tibialis posterior
what muscles cause eversion of the foot ?
Fibularis Tertius with fibularis longus and brevis
what separates the anterior and lateral compartments of the leg?
the anterior intermuscular septum
what muscles does the lateral compartment of the leg contain ?
fibularis longus and fibularis brevis
what are the muscles of the anterior compartment of the leg ?
Tibialis Anterior
Extensor Hallucis Longus
Extensor Digitorum Longus
Fibularis Tertius
what is the route of muscles fo the posterior compartment of the leg ?
They both attach to the fibula proximally and pass to the plantar surface of the bases of the 1st & 5th metatarsal respectively
what is special about the route of the fibularis longus muscle ?
it passes beneath the sole of the foot to reach the base of the 1st metatarsal
what is the axilla and what is its medial wall?
the pyramidal space inferior to the shoulder and superior to the arm pit - superolateral aspect of the chest
what is the axilla an important region for ?
An important “gateway” for structures entering or leaving the upper limb e.g. arteries, veins, nerves and lymphatics.
describe the position of the pectoralis major muscle ?
Forms the anterior wall of the axilla, and its lower border is contained in the inferior edge of the anterior axillary fold
what sort of movements does the pectoralis major help with and what is it an accessory muscle in ?
used in movements such as climbing and is an accessory muscle in inspiration
what is the axillary vein a contuination of?
the brachial vein
at what location does the brachial vein become the axillary vein ?
teres major muscle
where can the subclavian artery be palpated ?
where it crosses the first rib
when does the subclavian artery become the axillary artery ?
the lateral border of the first rib
what is the function of the brachial plexus ?
supplies the upper limb
what spinal nerves make up the brachial plexus ?
anterior rami of spinal nerves C5 – T1
what does the brachial plexus consist off from proximal to distal ?
- Roots: The anterior rami of C5 – T1 spinal nerves, which mix their nerve fibres to form trunks.
- Trunks: Combinations of roots, which give rise to divisions.
- Divisions: Each trunk divides to give anterior and posterior divisions, which combine to give cords.
- Cords: The cords are named according to their relationship to axillary artery - medial, lateral and posterior.
- Named Nerves: The cords combine to give the named nerves of the brachial plexus
Hence roots to trunks to divisions to cords to named nerves
what are the 3 trunks formed in the brachial plexus and what spinal nerves form them ?
superior supplied by C5&6
middle supplied by C7
and lateral supplied by C8
what are the 3 cords formed from the divisions of the trunks ?
Medial
lateral
posterior
what are the named nerves which the cords form?
The ulnar nerve
The musculocutaneous nerve
axillary nerve and radial nerve
median nerve
where do the roots and trunks lie in the brachial plexus ?
Mainly between the anterior and middle scalene muscles in the root of the neck.
where do the divisions in the brachial plexus mainly lie ?
immediately posterior to the subclavian vessels in the root of the neck (deep to the clavicle).
where do the cords in the brachial plexus lie ?
around the axillary artery distal to the first rib
what does the musculocutaneous nerve supply?
Supplies the coracobrachialis muscle, also supplies the other muscles of the anterior compartment of the arm: biceps brachii and brachialis muscles.
which compartment does the axillary and radial nerve enter and supply ?
posterior compartment of the arm
how is the axillary nerve located inrelation to the radial nerve ?
superior
What about the route of the axillary nerve makes it vulnerable to injury in shoulder dislocation or fractured neck of humerus?
It wraps around the posterior aspect of the surgical neck of the humerus.
what about the route of the radial nerve makes it vulnerable to injury during a mid-shaft humeral injury?
Wraps around the posterior aspect of the mid-shaft of the humerus
which is the most medial of the named nerves?
the ulnar nerve
what area of the arm does it pass into ?
the medial aspect of the arm
what does the median nerve form in terms of the “M-shaped” configuration of the named nerves within the axilla?
forms the middle of the ‘‘M-shaped’’ configuration
