Rank these positions from greatest to least amount of stress in L3 vertebrae:
Standing leaning forward
Lying flat
Sitting slouched
Standing with good posture
Sitting with good posture
1. Sitting slouched
2. Staning leaning forward
3. Sitting with good posture
4. Lying flat
Bone can withstand which type of stress the best?
Compression
True or false: A ductile material will always fracture at higher stresses than a brittle material?
False
Brittle material fracture with very little (if any) plastic deformation.
Ductile material fracture only after significant plastic deformation
What is the loading rate of a bone?
The speed at which the load is applied
During the Lumber extension what stresses are caused in the anterior and posterior portions of the vertebral discs in between vertebrae, respectively?
Tension; Compression
What type of load would cause a green stick fracture?
Bending load
Wolff's law states that
growth and remodeling of bone is dependent on the forces placed on it.
"The internal structure of trabecular bone is organized in part due to the type of load placed on it
In a torsional loading of bone what type of stress is felt along the neutral axis?
No stress
What disease is characterized by low bone density and is considered in part a lifestyle disease with no clear onset?
Osteoporosis
True or False: All bone growth arrests at approximately 18 years old
False
Which is characteristic of trabecular versus cortical bone?
-Has higher porosity
-Can undergo more strain before fracture
-larger plastic region on the stress strain curve
Materials which deform within the elastic region of the stress strain curve will?
They will store energy that may be recovered and return to their original shape when unloaded
True or False: The ultimate stress and fracture point of the material are always the same point on the stress and strain curve
False
Which of the following are true regarding the gastrocnemius muscle?
-its origin is on the femur
-it is a biarticular muscle
-its origin is on the tibia
-its action is dorsiflexion of the foot
It's origin is on the femur and it is a biarticular muscle
True or false: In lifting light objects from the ground for healthy individuals, allowing spinal flexion to occur is not a counter-indicted movement
True
What are the two main cues that suggest by M&M to develop a solid base for squatting?
-press your big toe into the ground
-external rotation at the hips to drive your knee outward
The closed packed position of a joint is best characterized by what?
Maximum surface contact of articulating surfaces
Which muscle can be an antagonist for both hip extension and knee flexion?
Rectus Femoris (it must be a biarticular muscle because it would have to cross both hip and knee)
Which of the following muscles are biarticular muscles?
-rectus femoris
-semimembranosus
-gastrocnemius
All of them
If the left hip flexes what else must occur in closed chain situation
Right hip flexion
Which of the following is most indicative of a low risk for superior dislocation of the hip joint?
Large Weinberg angle
A steep or larger inclination angle causes
Higher joint contact forces at the hip
The anteversion angle discussed is characterized by which of the following?
The morphological torsion of the femur from its proximal to distal end
The acetabulum generally face which three directions?
Anteriorly, laterally, and inferiorly
The ischiofemoral ligament is tensioned mainly by what hip position?
Hip extension
What ligament is inside the joint space of the hip joint and acts as a secondary stabilizer and a conduit for blood supply and inner action of the hip joint?
Ligamentum teres
What is the least stable hip position?
Flexed, adducted
An inclination angle greater than 125 degrees is characteristic of a hip that displays....?
Coxa valga
Excess anterior pelvic tilt during a squat will also cause excess movement of which of the following?
Lumbar extension
Which of the following does not participate in hip abduction?
-biceps femoris
-gluteus medius
-gluteus Maximus
-gensor fascia latae
Biceps femoris
In the first pull of the deadlift, the movement is dominated by which joint movement?
Knee extension
Which muscle is biarticular?
-gastrocnemius
-soleus
-both
Gastrocnemius
True or False: For a traditional dead lift in addition to the joint movements of the lower body you should allow a moderate amount of elbow flexion as you lift the bar to your hips
False
What is the origin of the adductor magnus?
Inferior ramps of pubis and is hail tuberosity
What is the target muscle in the traditional barbell deadlift
Gluteus Maximus
True or False: When performing a sumo deadlift it is important that the hips begin the lift positioned below the knees
False
For a sumo deadlift which muscle becomes a primary target of the exercise compared to the traditional deadlift?
Quadriceps femoris
Which joint of the ankle foot complex is the "ankle joint" that we classically think of?
Talocrural joint
What mechanical representation is used to describe the talocrural joint?
Tenon and mortise
Talocrural joint movement has how many degrees of freedom?
1 degree of freedom and mulitplanar movement
The talus trochlea has what shape?
Convex and characterized as a truncated cone
Which set of ligaments across the talocrural joint are stronger, deltoid or lateral collateral ligaments?
Deltoid
How many bones are part of the ankle foot complex?
28
Dorsiflexion tends to increase the toe ___________ angulation of the foot compared to the tibia
Out
What is the approximate range of motion for dorsiflexion from anatomically neutral?
20 degrees
The role of the transverse tarsal joint group is to?
Allow for accommodation of more proximal joint movement to maintain contact with the ground
In quiet standing what is the ratio of load bearing between the forefoot and the hindfoot?
2:1
During the dorsiflexion the talus __________ on the distal surface of the tibia
Rolls anteriorly and glides posteriorly
The talonavicular joint is a __________ joint while the calcanecuboid joint is a __________ joint
Ball and socket; saddle joint
Which muscle is a dorsiflexor?
-tibialis anterior
-gastrocnemius
-soleus
-popliteus
-flexor hallucis longus
Tibialis anterior
The longitudinal arch of the foot will increase with?
Active dorsiflexion of the toes and passive dorsiflexions of the toes
Which of the following positions most directly corresponds to the closed packed position of the foot?
Supinated
The tarsometatarsal joint of which ray has a mortise and tenon structure and is the most stable?
2
If the toe joint is modeled in motion capture modeling the _________ operation allowing the hind foot to lift off the ground with activation of the triceps surae
Metatarsophalangeal also joints
As the hindfoot supinate the tarsometatarsal joints must ___________ to keep the forefoot in contact with the ground
Pronate
The peroneus muscles cause which movement?
Plantarflexion and pronation
The fibula during dynamic activities tends to bear no more than what percentage of the load?
10 percent