Foundational Sciences Flashcards
Define the foundational position
- Same position as the anatomical position except the palms of the hands are facing the sides of the body
- Used in discussing rotation of the UE
Define distal versus proximal
- Distal means away from the trunk or a specific joint
- Proximal means towards the trunk or a specific joint
Purpose of the clavicle
- Connects the upper limb to the axial skeleton
- 1st bone to ossify
Function of the clavicle
- Holds the upper limb free from the trunk to allow freedom of movement
- Provides attachment for muscles
- Transmits forces from the upper limb to the axial skeleton at the sternum
Which ribs does the scapula cover
- 2-7th ribs
What vertebrae level does the inferior angle of the scapula sit at
- T7
Purpose of the coracoclavicular ligament
- Stabilizes the AC joint and prevents upward displacement of the humeral head
- Also prevents separation of the scapula from the clavicle
What 4 joints make up the shoulder joint
- Glenohumeral joint
- Acrominoclavicular joint
- Sternoclavicular joint
- Scapulothoracic articulation
What four muscles make up the rotator cuff
- Supraspinatus
- Infraspinatus
- Teres minor
- Subscapularis
How much ROM for abduction/flexion of the shoulder comes from the GHJ versus the scapula
- 120º from GHJ
- 60º from scapula
Biomechanics of the clavicle during shoulder elevation
- During the first 90º of abduction the clavicle elevates 35-45º at the SC joint
- For full elevate the clavicle requires 45-50º of clavicular backward rotation
How due the rotator cuff muscles stabilize/hold the humerus in the glenoid
- Supraspinatus and coracoacrominal arch guard superiorly
- Infraspinatus and tires minor guard posteriorly
- Subscapularis guards anteriorly
What is the most commonly fractured part of the proximal humerus
- Surgical neck
Normal carrying angles
- Men 10-15º
- Women 20-25º
Purpose of the interosseous membrane and oblique cord in the middle radioulnar joint
- Interosseous membrane stabilizes during pushing movements
- oblique cord resists distal displacement of radius during pulling movements
What is Volkmann’s ischemic contracture
- Permanent flexion of the hand at the wrist
- Passive finger extension is restricted and painful
Order of carpal bones from lateral to medial proximal and distal rows
- Proximal row: Scaphoid, Lunate, Triquetrum, Pisiform
- Distal row: Trapezium, Trapezoid, Capitate, Hamate
What carpal bones does the flexor retinaculum attach to
- Scaphoid and Tripezium
Which carpal bones is most commonly fractured and most commonly dislocated
- Fractured: Scaphoid; poor blood supply with likelihood of AVN
- Dislocated: Lunate (anteriorly)
What is the load bearing ratio of radius to ulna
- 60:40 radius:ulna
Which muscle is most active during grasping
- Extensor carpi radialis brevis
- Holds the wrist in extension
Which muscles radially deviate the wrist
- Extensor carpi radialis longus/brevis
- Flexor carpi radialis
Which muscles ulnarly deviate the wrist
- Flexor carpi ulnaris
- Extensor carpi ulnaris
How are the muscles of the forearm grouped into pronators, flexors, and finger flexors
- Pronators: pronator teres and quadratus
- Wrist flexors: FCR, FCU, and palmaris longus
- Finger flexors: flexor digitorum superficialis/profundus and flexor pollicis longus
Which ligament (palmar, transverse, collateral) becomes tight during MCP flexion
- Collateral ligaments
How much wrist extension is needed for optimal use of the hand
- 20-30º
Describe power versus precision grips
- Power: finger and wrist flexion with ulnar deviation
- Precision (prehension): holding an object between the fingertips
What does the opponent digits minimi do
- Hollows the palm for cupping the hand or for grasping a cylindrical object
Nerve damage and its effects on hand/wrist function
- Radial: affects maintenance of functional wrist position & release of an object
- Median: affects flexion of digits on radial side and precision grip
- Ulnar: affects flexion of ulnar Sid digits and power grip
What artery can a fracture of the femoral head effect
- Can disrupt the blood supply of the obturator artery to the head of the femur & cause aseptic necrosis (death in absence of infection)
What 3 ligaments cover the hip joint capsule and their function
- Illiofemoral (“Y” ligament) resists extension
- Ischiofemoral ligament resists extension and IR
- Pubofemoral ligament resists abduction
How much anteversion is normal
- Femoral neck is rotated 15º anterior to the long axis of the femur
- Too much ante version causes IR and toe in gait pattern
- Retroversion causes ER
What are the prime movers for IR and ER of the hip
- IR: gluteus medius and minimus anterior fibers
- ER: obturator externus and quadrates femoris
Importance of the Sciatic nerve
- Largest nerve in the body
- Passes under the Piriformis sometimes through it
- Splints into the tibial and common fibular (perineal) nerves in the distal thigh
What artery is the chief blood supply for the LE
- Femoral artery
- Pulse can be palpated in the femoral triangle, 2-3 cm inferior to the midpoint of the inguinal ligament
The collateral ligaments of the knee primarily restrain varus and valgus stresses especially between
- Full extension and 30º flexion
Describe the screw home mechanism of the knee joint
- Unlock: femur laterally rotates and tibia medially rotates in closed chain
In weight bearing how much compression force does the menisci transmit
- 50% in full extension
- 85% in 90º flexion
Which direction do the menisci move during flexion/extension
- They move posteriorly in flexion and anteriorly in extension
Which part of the menisci are partly vascular
- Outer 1/3 are partly vascular while the inner 2/3 is avascular
When is the ACL taut
- Taut during knee extension
What does the VMO (vastus medalis oblique) resist
- Resists lateral displacement of the patella out of the trochlear groove during closed chain
The most stress on the ACL from the quadriceps occurs from
- 45-0º of extension
Which hamstring muscles IR and ER the tibia
- IR: semimembranousus
- ER: biceps femoris
What muscles attach at the pes anserine
- Sartorius
- Gracilis
- Semitendinosus
Does the tibia have poor/good blood supply
- Relatively poor blood supply making even stable undisplayed fractures take up to 6 months to heal
Which bone in the foot ossifies first
- The calcaneous which is also the largest bone in the foot
Movements of the distal tibiofibular joint
- Fibula rotates laterally with DF to accommodate the wider portion of the talus
Movements of the talocrual joint
- DF and PF
Movements of the subtalor joint
- Triplanar motion
- Pronation: eversion, DF, and ABD of calcaneus
- Supination: inversion, PF, and ADD of calcaneus
How does the tibia rotate with supination and pronation at the subtalar joint
- Supination causes tibial ER
- Pronation causes tibial IR
Action of posterior tibialis in open chain
- PF and ankle invertor
Action of fibularis longus/brevis in open chain
- Evert the foot and ankle
Action of anterior tibialis, extensor digitorum longus (EDL), and extensor hallucinations longus (EHL)
- In open chain EHL and EDL extend the toes and all muscles DF the ankle
What structures support the arches of the foot
- Longitudinal: long palmar ligament supports the lateral aspect
- Medial: supported by the fibularis longus, posterior tibialis, and intrinsic muscles & the plantar calcaneonavicular ligament (Spring lig)
- Transverse: supported by metatarsal heads & musculoligamentous complex preventing metatarsals from spreading out
Regional characteristics of vertebrae
- Cervical: foramina of transverse processes contain vertebral arteries
- Thoracic: facets on vertebral bodies for articulation with ribs
- Lumbar: massive bodies & sturdy laminae for support of the body weight
- Sacrum: fused vertebrae with 4 foramina on each side
- Coccygeal: tiny, incomplete, & fused vertebrae
A teardrop fracture is the result of
- Compression of the anterior aspect of the vertebral body in which a triangular fragment is split from the vertebral body anteriorly
Function of the intrinsic and extrinic muscles of the back
- Superficial: trapezius and latissimus dorsi conneting the upper limbs to the trunk & provide movement of the limbs
- Intermediate: serratus posterior are respiratory muscles
- Deep: erector spinae maintain the posture & move the vertebral column & head
Function of the platysma
- Assists in depressing the mandible
- Draws mouth inferiorly & is one of the facial expression muscles
- Superficial neck muscle
What is the articular disc of the TMJ made of
- Made of dense fibrous connective tissue & fibrocartilage & is largely avascular & aneural
Movements of the TMJ
- Mandible elevation: temporalis, masseter, & medial pterygoid
- Protrusion: Lateral/Medial pterygoids protrude and posterior fibers of temporals muscles retrude mandible
Define coxa vara
- femoral neck shaft angled inward (angle of inclination <125º)
Define coxa valga
- femoral neck shaft angled outward (angle of inclination >125º)
Define anteversion
- femoral torsion markedly >15º
Define retroversion
- femoral neck torsion markedly <15º
Define internal tibial torsion
- distal aspect of tibia rotated or twisted medially as compared to its proximal end
Define genu varum
- knees are lateral in relation to the ankle (“bowlegged”)
Define genu valgum
- knees come together or almost touch (“knock-kneed)”)
Define equinus
- the toe is in a down position, DF limitation of the ankle
Define talipes equinovarus
- ankle & foot are down and in (“club foot”)
Define valgus heel
- the rear foot is deviated toward the outside resulting in a pronated heel
Describe the different levers in the body
- First class: fulcrum is located b/w the force and the resistance (seesaw on playground)
- Second class: fulcrum is at one end, the resistance is in the middle, and the force is at the other end (wheelbarrow)
- Third class: fulcrum is at one end, the force is in the middle, and the resistance is at the other end (most common lever in the body, advantage for ROM)
Describe the plumb line through the body in the sagittal plane
- Through the external meatus of the ear, acromion process & the hip joint
- Posterior to patella
- Anterior to the lateral malleolus
In perfect static posture which muscle is most active
- Soleus
- Maintains the body’s balance
Define arthrokinematics versus osteokinematics
- Arthro: movements that occur from one joint surface to another
- Osteo: movements that occur between 2 bones
What percentage of gait does stance and swing phase make up
- Stance phase: 60%
- Swing phase: 40%
When are the abdominals and trunk muscles active during gait
- Abdominals are active throughout
- Trunk extensors & rotators active during foot flat
- Ipsilateral erector spinae are active during toe off as the contralateral limb is loaded
Define isometric exercise
- A static contraction at a particular point in the ROM
- Precaution: Valsalva’s maneuver should be avoided; in pts with vascular/cardiac disease & concerns of causing sharp increase in BP
Define isotonic exercise
- Exercise occurs throughout the ROM with the same resistance & variable speed of movement
- Precautions: Increased force and subsequent muscle soreness may occur with eccentric contractions
Define isokinetic exercise
- Occurs at a constant, preset speed in which the resistance is variable & accommodates as the force of contraction varies throughout the ROM
Define aerobic exercise
- Exercise that promotes circulation & efficient use of oxygen in the vascular & cardiopulmonary systems
- Performed at target HR for at least 20 min & involving large muscles groups in rhythmical movements
Training effects of aerobic exercise
- Cardiac: decreased resting/submaximal HR, BP at rest; increased cardiac output & stroke volume during sub maximal exercise
- Pulmonary: Increased tidal volume, oxygen extraction from the blood; decreased ventilation
What temperature should a pool be for intense training versus rehabilitation
- Intense training: 27-28ºC (81-83ºF)
- Rehabilitation: 33-34ºC (91-93ºF)
Cardiopulmonary responses to water immersion
- SV & CO increase while HR stays the same or slightly decreases
- Hydrostatic pressure on chest can decrease IRV & may reduce FVC
- Target HR should be established in the pool due to lower HR during deep-water exercise compared to land-based exercise
Cardiac changes with aging
- Sedentary individuals have 2x the rate of VO2 max decline
- Age predicted max HR decreases
- CO may decline unless there in an increase in SV
Muscular changes with aging
- > 65 muscle strength decreases from 24% to 45%
- Muscle mass reduces
- Fiber size decreases
Neurological changes with aging
- Nerve conduction velocity declines 10%
- # of spinal cord axons declines & reduces reaction time
Pulmonary changes with aging
- Static & dynamic pulmonary functions decline with age
Skeletal changes with aging
- > 60 bone mass may reduce by 30-50% which could result in osteoporosis
