MSK Flashcards
What is a class 1 lever
the two forces are on either side of the fulcrum
what is the effort force
the one that is trying to cause the movement - typically the muscle
What is the resistance force
the opposing movement - dumbbell, gravity
Example of a Class one lever and explain
triceps contraction - elbow is the fulcrum, effort force is the tricep and weight is the resistance
What is a class 2 lever
two forces are on one side but the resistance is in between the effort force and fulcrum
What is an example of a class 2 lever and explain
calf raise - fulcrum is at the metacarpal heads, resistance is gravity going down and the effort force is the calf pushing up
what is the most common lever in the body
class 3
What is a class three lever
the effort force is in between the fulcrum and resistance
What is an example of a class 3 lever and explain
elbow flexion - effort is at the biceps insertion , fulcrum is the elbow and resistance is the forearm/weight
Describe convex on concave movement
the convex surface will move opposite the direction of the shaft of the lever
Describe concave on convex movement
the concave surface moves in the same direction as the shaft of the lever
Describe convex- concave rule in the spine
At the atlanto occipital joint it is convex on concave. Below this it is concave on convex
What are the 3 types of normal end feels of a joint
Soft: soft tissue approximation
Firm: capsular or ligament stretch
Hard: bone or cartilage meet
What are the 5 types of pathological end feel of a joint
Boggy: edema or joint swelling Firm with decreased elasticity: fibrotic Rubbery: muscle spasm Empty: loose, then hard - pain guarding Hyper mobility: end feel later than opposing side
The head of the humerus is retroverted ___ degrees
20-30*
the scapula sits over ribs…
2-7
Glenoid fossa faces ____, ____ and ______
anterior, lateral and superior
scapular plane is at ___degrees
30
Sternoclavicular joint arthrokinematics
clavicle is convex superior to inferior and concave anterior to posterior
Shoulder joint capsule is supported by
RTC tendons and triceps LH tendon.
Which part of the shoulder joint capsule is most unstable
inferior
The coracohumeral ligament prevents
inferior dislocation
The coracohumeral ligament is taut in
ER
During elevation of the humerus it begins to ER at what degree of elevation
75
Scapulohumeral rhythm ratio and pure GH motion
2:1, GH motion only for the first 30-60 degrees
Radioulnar joint proximal, concave and convex
Radius is convex, ulna is concave
Radioulnar joint distal, concave and convex
Radius is concave and ulna is convex
Ulna to carpals concave/convex
ulna is convex and triquetrium is concave
Radius to proximal carpals concave/convex
Radius is concave and the scaphoid/lunate is convex
metacarpal heads are convex or concave
convex
First CMC joint connects to which carpal
trapezium
first metacarpal base convex/concave
it is convex medial/lateral and concave AP
median nerve innervates what part of the hand
supplies palmar side of 1st, 2nd, 3rd and lateral half of the 4th digit as well as the dorsal side PIP to tips of 2nd, 3rd and half of 4th again as well
ulnar nerve innervates
palmar and dorsal side hypothenar eminence, 5th digit and medial half of the fourth digit
radial nerve innervates what part of hand
dorsal side of first, 2nd, 3rd and medial half of 4th finger and back side of hand not innervated by ulnar nerve
First CMC arthrokinematics for FLEX/EXT and ABD/ADD
Convex on concave for ABD/ADD
Concave on convex for FLEX/EXT
arthokinematics of wrist motions
scaphoid lunate dorsal glide during flexion, ventral glide with extension. Radial glide with ulnar deviation and ulnar glide with radial deviation.
Normal angle of inclination for the femoral neck
115-125
Coxa valga is
greater than 125
Coxa vara is
lower than 115
the normal angle for femoral neck in frontal plane
antetorsion of 10-15 degrees
anteversion pathological angle is
greater than 25
retroversion angle
less than 10
someone with excessive anteverison will
in toe
someone with excessive retroversion will
out toe
hip labrum is thickest at what part
superior
The Iliofemoral ligament or Y ligament origin
both from the AIIS
The iliofemoral ligament is taut with
EXT and ER for both
the superior part is taut with ADD
the inferior part is taut with ABD
The pubofemoral ligament origin
iliopectineal eminence, superior rami of pubis
Pubofemoral ligament is taut with
EXT, ER and ADD
Ischiofemoral ligament origin
Ischium to posterior acetabulum and greater troch
ischiofemoral ligament is taut with
EXT, IR, and ABD
what is the zone orbicularis
ligament that surrounds the femoral neck to help support it in the acetabulum
inguinal ligament origin/insert
ASIS to pubic tubercle
which femoral condyle has a longer SA
lateral
which femoral condyle descends more inferiorly
medial
which tibial condyle is more is more stable
medial
MCL limits
knee ER
ACL origin and insertion
anterior intercondylar fossa to the medial side of the lateral femoral condyle
The ACL limits
tibial forward translation and IR of the tibia during flexion
PCL origin and insertion
posterior intercondylar fossa to the lateral side of the medial epicondyle
Transverse ligament of the knee connects
the two menisci
Meniscopatellar ligament does what
pulls the menisci forward during extension
what does the alar fold do in the knee
keeps the patella in contact with the femur
differences between MM and LM, size shape and amount of movement
MM is large and C shaped
LM is smaller and circular
MM can move 6mm and the LM can move 12mm
MM has attachments with
semimembranosus, MCL and capsule
LM has attachments with
popliteus
The menisci follow the tibia during
flexion and extension
the menisci follow the femur during
IR, and ER
During the flexion the femoral condyles roll
posterior and glide anterior
During extension the femoral condyles roll
anterior and glide posterior
There is pure rolling of the femoral condyles during gait for the first ___ degrees of knee flexion
10-15
During gait the tibia will begin to __ at __ of knee flexion
IR, 20
screwhome mechanism is during the last __ degrees of EXT
5
reasons for the screw home mechanism
The lateral femoral condyles move more freely causing more tibial rotation in the posterior direction
rolling occurs more on lateral condyle
MCL attachment to the MM causes tautness in EXT and stops gliding with continued glide of the LM gliding forward creating IR femur/ER of tibia
Twisted cruciate ligaments prevent IR
Lateral angle of pull of the quads
Fibular head movement during angle motions
move superior and posterior, with ER of shaft during DF and inferior and anterior with IR of shaft during PF
What are the three articulation of the talocrural joint
Tibiofibular, tibiotalar and fibulotalar
The subtler joint 2 articulations
anterior talocalcaneal and posterior talocalcaneal
key tarsal bone to the lateral arch of the foot
cuboid
Plantar fascia windlass effect
dorsiflexion of the MTP joints causes tightening which causes supination of the calcaneus and inversion of the subtler joint creating a rigid lever for push off during gait
conjuct rotations of the talus during DF to PF
the talus rotates medially 30 degrees
arthrokinematics of the Talus during open chain PF and DF
talus glides anteriorly on the mortise during PF.
talus glides posterior on the mortise during DF
Arthrokinematics of the tibia during closed chain PF and DF
tibia glides posterior on the talus during PF
tibia glides anterior on the talus during DF
Subtalar joint oblique axis is __ degrees from horizontal and __ degrees from midline
42 and 16
with a high inclination of axis, movement at subtalar joint is _______ in the transverse plane and _____in the frontal plane
increased, decreased
with a low inclination of axis, movement at the subtler joint is ____ in the frontal plane and ____ in the transverse plane
increase, decrease
uncinate joints
are found at C3-C7 and limit lateral flexion
Rule of 3s
T1-T3:spinous processes are even with transverse process of same level
T4-T6: spinous process one half level below their transverse process
T7-T9: spinous process is one full level below their transverse process
T10: full level
T11: half level
T12:even
the annulus fibrosis is made of
concentric layers composed of collagen type II fibers and fibrocartilage and is 65% water
What is the nucleus pulposus made of
minimum colalgen Type I, mostly water 70-90% and proteoglycans
Which part of the spinal cord is avascular and aneural
the nucleus pulposis
the nucleus pulposis makes up ____% of the height of the spine
20-33%
what is the purpose of the vertebral endplate
provides passive diffusion of nutrients
where does the spinal cord terminate
L1-L2
Muscles that contribute to inspiration
diaphragm, levator costarum, external intercostals, anterior internal intercostals
muscles that contribute to forced expiration
internal obliques, transverse abdominaux, external obliques, posterior internal intercostals, rectus abdominus
muscles that contribute to spine extension
erector spinae, transversospinalis, interspinales, rotatores intertransverarii
muscles that contribute to spine flexion
rectus abdominus, external oblique, internal obliques, psoas minor
muscles that contribute to spine lateral flexion
QL
muscles that contribute to spine rotation
rotators, internal/external oblique, intertransversarii, transversospinalis
diaphragm innervation
C3-C5 phrenic
temporomandibular joint range of opening
40 mm
TMJ amount of rotation
25mm
TMJ amount of translatory glide
15mm
typical symptoms of vascular claudication
pain is consistent no matter the position
pain is brought on by physical activity and relieved within 5 minutes of rest
pain described as numbness
decreased/absent pulses
effects of forward head posture on the mandible
elevated and retruded
effects of forward head posture on TMJ
posterior close packed position
effects of forward head posture on hyoid
elevated
effects of forward head posture on cervical spine
upper cervical is extended, middle and lower loose lordosis
effects of forward head posture on first and second ribs
elevated
MRI T1 ___is white in color and is used to asses ____
fat, bony anatomy
MRI T2 ____ is white in color and is used to assess ____
water, soft tissue
how does a bone scan work
chemical laced with radioactive tracer is injected and settles in areas with high metabolic activity of bone
myelography is used to assess however is not as good an option compared to _____
discs and stenosis; MRI/CT
muscle grading
5/5: lift or hold against gravity with max resistance
4 grades: “good”lift or hold against gravity with mod to min resistance
3 grades: “fair” lift or hold against gravity - no resistance.3- some assistance may be required to complete the motion
2 grades: “poor” gravity eliminated with 2- needing assistance
1/5: trace, can be seen or felt but no movement
0/5: no contraction seen or felt
Activities that create anterior torsion
squatting, lifting, lowering, pregnancy, hip at 90 with axial loading, golfing/batting/tennis
