Movement Science week 4-6 (exam 2)

What ligament prevents posterior translation of the femur on the tibia?

ACL

ACL

PCL (your response)

MCL

LCL

ACL

name the 3 rockers of the foot and ankle

1st Rocker (heel rocker)
• From heel contact to foot flat

• 2nd Rocker (ankle rocker)
• From Foot flat to foot flat (the entire time the foot is flat on the ground)
• Forward tibial movement over the talus

• 3rd Rocker (forefoot rocker)
• From the beginning of “heel off” to “toe off”

What tissue is likely to be stressed during an inversion ankle sprain?

An inversion ankle sprain stresses the lateral ligaments of the ankle, and most commonly:

1. Anterior talofibular ligament (ATFL) – most frequently injured due to its position and orientation.

what range of motion in the TF joint does walking, climbing stairs, descending stairs, sitting down, tying a shoe, and lifting an object take?

walking - 67

climbing stairs - 83

descending stairs - 90

sitting down - 93

tying shoe - 106

lifting an object 117

name the triplanar motions of pronation

DF

eversion

abd

name the triplanar motions of supination

PF

inversion

adduction

explain the difference between pes cavus and pes planus

Pes cavus = excessively high arch, (poor shock absorption)
Pes planus = collapsed or absent arch. (medial foot stress)

What are the primary functions of the joints of the foot during gait?

Functions:
Contact with the ground - initiates stance phase and adapts to surface
Shock absorption - subtalar and midfoot
Stability - supports body weight
forward Propulsion

Please describe the arthrokinematics of the great toe (MTP) during open chain extension and
include the directions for the roll and slide

1. Identify the concave segment
Phalanx
2. Identify the convex segment
Metatarsal
3. Determine which segment is moving
Phalanx
4. Define the roll/slide relationship
Concave on convex (SAME)
5. Identify the direction of the roll
• Direction of movement of the segment away from the joint
Dorsal
6. Determine the direction of the slide
Dorsal (superior for foot)

What is the normal range of acetabular anteversion angle?

10-15 degrees

15-20 degrees

20-25 degrees

25-30 degrees

15-20 degrees

Which muscles are considered primary stabilizers of the hip joint?

Gluteus maximus, hamstrings

Iliopsoas, rectus femoris

Piriformis, gemelli, obturator internus

Adductors, quadriceps

Piriformis, gemelli, obturator internus

What is the open pack position for the hip joint?

Extension, abduction, internal rotation

Flexion, abduction, external rotation

Flexion, adduction, internal rotation

Extension, adduction, external rotation

Flexion, abduction, external rotation

What is the maximum congruency position for the hip joint?

Flexion, abduction, external rotation

All-fours position

Supine position

Seated position

All-fours position

A patient has excessive femoral anteversion. Which compensatory movement would they likely exhibit during gait to maintain their toes pointing forward during gait?

Excessive knee flexion

Excessive knee extension

Externally rotated tibia

Internally rotated tibia

Externally rotated tibia

In a patient with weak abdominal muscles, what would you expect to observe during the active straight leg raise test?

Increased lumbar lordosis

Decreased lumbar lordosis

Pelvis remains stable

Inability to raise the leg

Increased lumbar lordosis

A patient is prescribed hip abduction exercises. Based functional performance of the hip during gait, at what hip joint angle would the patient be able to produce the greatest force?

10 degrees of abduction

0 degrees (neutral)

10 degrees of adduction

20 degrees of abduction

10 degrees of adduction

If a patient has a femoral neck fracture which artery is most likely to be compromised?

Femoral artery

Obturator artery

Medial circumflex femoral artery

Sciatic artery

Medial circumflex femoral artery

A patient is experiencing sciatic nerve pain. Which muscle is most likely contributing to the compression of the sciatic nerve?

Gluteus maximus

Iliopsoas

Adductor magnus

Piriformis

Piriformis

A patient has a hip impingement syndrome. Which hip position would be most likely to reproduce their symptoms?

Flexion, adduction, internal rotation

Flexion, abduction, external rotation

Extension, adduction, internal rotation

All fours position

Flexion, adduction, internal rotation

What is the shape of the tibial plateau?

Highly convex

Highly concave

Relatively flat

V-shaped

Relatively flat

What is the term used to describe knee hyperextension?

Genu valgum

Genu varum

Genu recurvatum

Genuflect

Genu recurvatum

What is the mechanism that causes the obligate tibial external rotation near full knee extension?

Screw-home mechanism

Bowstring mechanism

Pivot-shift mechanism

Lachman mechanism

Screw-home mechanism

What is the primary function of the menisci in the knee joint?

Increase joint congruency

Limit joint mobility

Increase joint stability

All of the above

Increase joint congruency

What is the primary mechanism of injury for the lateral collateral ligament (LCL)?

Valgus force with the foot planted

Varus force with the foot planted

Hyperextension

Hyperflexion

Varus force with the foot planted

What is the most common direction of patellar dislocation?

Medial

Superior

Inferior

Lateral

Lateral

A patient presents with a knee injury after being hit from the lateral side of their knee while their foot was planted. Which ligament is most likely injured?

Medial collateral ligament (MCL)

Lateral collateral ligament (LCL)

Anterior cruciate ligament (ACL)

Posterior cruciate ligament (PCL)

During a physical examination, a clinician performs the anterior drawer test on a patient's knee and finds increased anterior translation of the tibia on the femur with a lack of a firm end-feel. What is the most likely injury?

Medial collateral ligament (MCL) sprain

Lateral collateral ligament (LCL) sprain

Anterior cruciate ligament (ACL) tear

Posterior cruciate ligament (PCL) tear

Anterior cruciate ligament (ACL) tear

A patient reports difficulty in fully extending their knee and having to use their quadriceps muscle to maintain standing. What is the most likely issue?

Lack of full knee extension range of motion

Patellofemoral joint instability

Meniscal tear

Ligament sprain

Lack of full knee extension range of motion

A patient reports increased anterior knee discomfort and pain during deep knee flexion activities. Which of the following statements is most accurate?

The patellofemoral contact area decreases with increasing knee flexion angles

The patellofemoral contact area increases with increasing knee flexion angles

The patellofemoral contact area remains constant throughout the range of knee flexion

The patellofemoral joint has no contact area during knee flexion

The patellofemoral contact area increases with increasing knee flexion angles

Please explain in biomechanical terms why it is important to regain knee extension after total knee replacement (TKR) as it relates to gait and overall weight bearing function.

ADLs require full knee extension
Limits quads energy expenditure
Knee extension at heel strike and other positions
Knee extension is the closed pack position- stability
Tibia and femur meniscus good contact area

Compare and contrast the contact forces in the patellofemoral joint during open chain knee
extension and a closed chain squat. In addition, describe the relationship between the contact of the femur and the patella as an individual extends their knee from 90 degrees of flexion to full extension.

Open Chain Knee Extension (e.g., leg extension machine):

• Contact Forces:

  • Increase as the knee extends toward full extension (0°).

  • Highest stress occurs between 45° and 0° due to increasing quadriceps force and smaller contact area on the patella.

• Reason:

  • The quadriceps must generate more force to move the tibia, increasing patellofemoral joint compression.

  • Contact area between patella and femur decreases, concentrating force over a smaller area = higher joint stress.

Closed Chain Squat (e.g., bodyweight squat):

• Contact Forces:

  • Increase as the knee flexes deeper into squat (90° and beyond).

  • Highest patellofemoral stress occurs in deeper flexion due to higher joint reaction forces and greater contact area.

• Reason:

  • Weight-bearing increases compressive load.

  • Larger contact area between patella and femur spreads out the forces somewhat, but the total compressive force is greater.

Forces in squat > open chain 7x BW

Consider the standing hip abduction exercise shown in the picture below. Does the exercise get easier or more difficult (require more or less hip abduction force) as she moves from anatomic position to a hip abduction angle of 30 degrees? What biomechanical concepts are involved?

As the hip abducts from anatomical position to 30°, the exercise becomes more difficult because the external moment arm increases, requiring the hip abductors to produce more force to counteract greater gravitational torque.

What structural feature contributes most to variability in hip joint alignment among individuals?
A. Patellar tendon length
B. Acetabular orientation
C. Femoral epicondyle angle
D. Greater trochanter height

B. Acetabular orientation

What artery is a key blood supply to the femoral head?
A. Popliteal artery
B. Obturator artery
C. Medial circumflex femoral artery
D. Lateral femoral cutaneous artery

C. Medial circumflex femoral artery

Which phase of gait is associated with maximum hip extension?
A. Initial contact
B. Midstance
C. Terminal stance
D. Swing phase

C. Terminal stance

A common sign of gluteus medius weakness during gait is

B. Trendelenburg gait

explain cora valga vs cora vara

Coxa Valga:

• Increased angle (>135°)

• Femoral neck is more vertical

• Leads to:

  • Decreased hip stability

  • Increased risk of dislocation

  • Reduced abductor leverage

Coxa Vara:

• Decreased angle (<120°)

• Femoral neck is more horizontal

• Leads to:

  • Increased shear stress on the femoral neck

  • Shortened limb

  • Improved abductor mechanical advantage, but higher fracture risk

Key difference:

• Valga = ↑ angle, longer limb, less stable

• Vara = ↓ angle, shorter limb, more stable but structurally weaker

open pack position of the hip

~30° flexion, ~30° abduction, slight ER

explain gait using both traditional and rancho los amigos methods including percent and double limb support

• Heel Strike (Initial Contact) 0%

• Foot Flat (Loading Response) 0-10%

• Midstance 10-30%

• Heel Off (Terminal Stance) 30-50%

• Toe Off (Preswing) 50-60%

• Acceleration (Initial Swing) 60-70%

• Mid Swing 70-90%

• Deceleration (Terminal Swing) 90-100%

double limb support 0-10%, 50-60%

Explain the clinical significance of Ward’s triangle in the femur.

It’s a weak, low-density area with fewer trabecular lines, making it prone to fractures.

(T/F) The screw-home mechanism involves internal tibial rotation during knee extension.

False (It involves external rotation in open chain)

The __________ muscle initiates tibial internal rotation to unlock the knee.

Popliteus

What percentage of the gait cycle is spent in stance phase?

A. 40%
B. 50%
C. 60%
D. 70%

60

(T/F) Rancho Los Amigos terminology is more adaptable for describing atypical gait.

True

Which activity requires the greatest knee flexion?

A. Walking
B. Sitting
C. Tying shoes
D. Descending stairs

Tying shoes (~106°)

(T/F) The patellofemoral joint experiences the highest compressive force during walking.

False (Deep squats cause higher forces)

Describe in your own words, how cartilage receives nutrients despite its poor blood supply. How does mechanical loading (exercise, stretching, etc.) facilitate tissue growth and remodeling in cartilage? Also, describe how a partial meniscectomy (meniscus removal) impacts compressive loading at the knee

Cartilage has no blood supply, so it gets nutrients through diffusion from synovial fluid. Joint movement helps pump nutrients in and waste out.

Exercise and stretching apply pressure, which stimulates cartilage cells and improves fluid exchange, supporting growth and repair.

Removing part of the meniscus reduces shock absorption, leading to increased stress on cartilage and higher risk of joint degeneration.

Label the convex and concave components of hip. Describe the roll and slide (the same or opposite directions) for open and closed chain flexion.

open chain: supine leg raises

• leg on hip (convex on concave)

• roll and slide in opposite direction

• femur moving, acetabulum is stationary

• motion: roll is anterior, slide is posterior

close chain:

• hip on leg (concave on convex)

• roll and slide in same direction

• femur is stationary, acetabulum is moving

• motion: roll and slide both anterior

Percent of gait cycle (reference limb) for the following:

Initial contact:

Toe off:

duration of stance phase

double limb support phase (2)

0%

60%

0-60%

(0 to 10%) and (50-60%)

Why does the second double limb support phase begin at 50%?

because that’s when the opposite (contralateral) foot makes initial contact with the ground to transfer weight

Define the following:

a. Step length:

b. Stride Length:

c. Step width:

d. Foot Progression Angle

a. Step length: The distance between the heel contact of one foot and the heel contact of the opposite foot.

b. Stride length: The distance between successive heel contacts of the same foot.

c. Step width: The side-to-side distance between the feet during walking.

d. Foot Progression Angle: The angle between the direction the foot points and the line of forward progression.

Describe the 3 rockers, and discuss the following: a. When each rocker begins and ends using appropriate gait terminology. What mechanics are occurring in the foot for each rocker.

1st Rocker: Heel Rocker (plantarflexion)

• Description: The heel acts as a pivot point as the foot lowers to the ground after initial contact.

• When it occurs:

  • Begins: Initial Contact (0% gait)

  • Ends: Foot Flat / Loading Response (~10% gait)

2nd Rocker: Ankle Rocker (dorsiflexion)

• Description: The tibia rolls forward over the stationary foot, allowing controlled forward progression.

• When it occurs:

  • Begins: Loading Response (~10% gait)

  • Ends: Heel Off / Terminal Stance (~30–40% gait)

3rd Rocker: Forefoot Rocker (plantarflexion)

• Description: The forefoot acts as a pivot point as the heel lifts, preparing for push-off.

• When it occurs:

  • Begins: Heel Off / Terminal Stance (~30–40% gait)

  • Ends: Toe Off / Pre swing (~50–60% gait)

Describe the Sagittal plane motions for the ankle, knee, and hip. Using your knowledge gained from anatomy, based on the gait motion, what muscle affects the internal moment, and how the muscle contracts with each phase of gait.

a. Ankle:

b. Knee:

c. Hip:

a. Ankle

• Motion: Plantarflexion and dorsiflexion

• Muscle:

  • Tibialis anterior creates dorsiflexion moment, contracting eccentrically during initial contact/loading to control foot lowering and concentrically during swing to clear the foot.

  • Gastrocnemius-soleus complex produces plantarflexion moment, contracting eccentrically during midstance to control tibial advancement and concentrically during terminal stance/preswing for push-off.

b. Knee

• Motion: Flexion and extension

• Muscle:

  • Quadriceps generate knee extension moment, contracting eccentrically during loading response to control knee flexion and concentrically during midstance to extend the knee.

  • Hamstrings create knee flexion moment, contracting concentrically during initial swing to flex the knee for foot clearance and eccentrically during terminal swing to decelerate knee extension.

c. Hip

• Motion: Flexion and extension

• Muscle:

  • Iliopsoas generates hip flexion moment, contracting concentrically during preswing and initial swing to advance the limb.

  • Gluteus maximus and hamstrings produce hip extension moment, contracting eccentrically during terminal swing to decelerate hip flexion and concentrically during loading response to stabilize and extend the hip.

Describe the Frontal plane motions for the ankle and hip. Using your knowledge gained from anatomy, based on the gait motion, what muscle affects the internal moment, and how the muscle contracts with each phase of gait.

Ankle (Frontal Plane)

• Motion: Inversion and eversion

• Muscle:

  • Tibialis posterior controls inversion, contracting eccentrically during stance to prevent excessive pronation (eversion).

  • Fibularis (peroneus) longus and brevis control eversion, contracting concentrically during stance to stabilize the lateral foot and assist propulsion.

Hip (Frontal Plane)

• Motion: Abduction and adduction

• Muscle:

  • Gluteus medius and minimus produce hip abduction moment, contracting eccentrically during loading response to control pelvic drop on the swing side (prevent Trendelenburg sign) and concentrically during midstance to stabilize the pelvis.

  • Adductor muscles assist with adduction moments, typically less active during normal gait.

Describe the motion of the trunk and pelvis during stance and swing phase of gait.

• Stance phase: The pelvis rotates forward on the side of the swinging leg (approximately 5°), and the trunk remains relatively stable but slightly rotates opposite the pelvis to counterbalance. The pelvis also tilts slightly downward on the swing side (pelvic drop), controlled by the hip abductors of the stance leg to maintain lateral stability.

• Swing phase: The pelvis continues its forward rotation as the leg swings through, while the trunk rotates slightly in the opposite direction to the pelvis to help with balance and momentum. Overall, these coordinated motions minimize vertical and lateral displacement of the center of mass for efficient gait.

Which vertebral joint has the LEAST rotation available?

 

C1-C2

C4-C5

T4-T5 

L2-L3

L2-L3

What is the correct arthrokinematic motion at the TMJ for mouth opening?

 

Posterior roll then anterior glide

Posterior roll then posterior glide

Anterior roll then posterior glide

Anterior roll and glide

Posterior roll then anterior glide

What is the primary contributor to the directions of motion available in each of the spinal regions (cervical, thoracic, lumbar)?

 

Facet joint orientation

Ligamentous tension

Disc height

Muscle line of force

Facet joint orientation

What is the open pack position of the spine at T6-T7?

 

Neutral flexion/extension

Full flexion

Full extension

Extension with side bending

Neutral flexion/extension

Which muscle group stabilizes the pelvis in the front plane for single limb support, and prevents the opposite side from dropping?

gluteus medius 

gluteus maximus

semimembranosus and semitendinosus

adductor magnus

gluteus medius 

Which muscle is essential for acting eccentrically to prevent foot slap?

 

gastrocnemius muscle

tibialis posterior

tibialis anterior

fibularis brevis

tibialis anterior

Weight acceptance is comprised of which phases of the gait cycle?

 

loading response and mid stance

initial contact and loading response

terminal stance and pre-swing

mid stance and terminal stance

initial contact and loading response

Which bony structure forms the site of articulation for the TMJ?
A) Mandibular condyle
B) Mandibular fossa
C) Hyoid bone
D) Zygomatic arch

B) Mandibular fossa

During the initial phase of mouth opening, what type of mandibular movement occurs?
A) Anterior-inferior translation
B) Posterior rotation
C) Posterior-superior translation
D) Lateral rotation

B) Posterior rotation

What is the closed-pack position of the TMJ?
A) Teeth slightly apart, tongue on roof of mouth
B) Teeth clenched
C) Mouth fully open
D) Mandible protruded

B) Teeth clenched

Which muscle is primarily responsible for mandibular elevation?
A) Lateral pterygoid
B) Masseter
C) Mylohyoid
D) Digastric

B) Masseter

Which rib motion is described as a "pump handle" movement?
A) Lower ribs
B) Upper ribs
C) Middle ribs
D) Floating ribs

B) Upper ribs

Which ribs move in a "bucket handle" motion during inspiration?
A) Ribs 1–3
B) Ribs 4–7
C) Ribs 8–10
D) Ribs 11–12

B) Ribs 4–7 (middle ribs)

During forced expiration, which muscle pulls ribs inward to compress the thoracic cavity?
A) External intercostals
B) Scalenes
C) Internal intercostals
D) Diaphragm

C) Internal intercostals

What unique feature does the axis (C2) have?
A) Large concave superior facets
B) Dens (odontoid process) projecting upward
C) Transverse foramina for vertebral artery
D) Long prominent spinous process

B) Dens (odontoid process) projecting upward

What is the primary motion allowed at the Atlanto-Occipital (AO) joint?
A) Axial rotation
B) Flexion and extension ("Yes" motion)
C) Lateral bending
D) No motion

B) Flexion and extension ("Yes" motion)

What ligament stabilizes the Atlanto-Axial (AA) joint?
A) Tectorial membrane
B) Cruciform ligament (especially transverse portion)
C) Ligamentum nuchae
D) Anterior longitudinal ligament

B) Cruciform ligament (especially transverse portion)

What is the open-pack position for cervical facet joints?
A) End-range extension
B) Neutral position
C) Full flexion
D) Maximum rotation

B) Neutral position

Which muscle group is responsible for bilateral contraction causing spine extension?
A) Transversospinalis
B) Erector spinae
C) Interspinales
D) Rectus abdominis

B) Erector spinae

The vertebral artery enters the transverse foramen at which cervical vertebra?
A) C1
B) C3
C) C6
D) C7

C) C6

During right cervical side bending, which facet joint closes?
A) Left facet
B) Right facet
C) Both open
D) Both close

B) Right facet

Kinetic gait analysis primarily focuses on:
A) Joint angles and movement patterns
B) Forces and torques during walking
C) Visual observation of gait
D) Muscle activation timing

B) Forces and torques during walking

Which method of gait analysis is commonly used in clinical settings due to its low cost and ease?
A) Kinetic analysis
B) Kinematic analysis
C) Observational gait analysis
D) Instrumented gait lab analysis

C) Observational gait analysis

Contralateral pelvic drop during gait is commonly an indicator of weakness in which muscle?
A) Gluteus maximus
B) Gluteus medius
C) Quadriceps
D) Hamstrings

B) Gluteus medius

A common cause of hip hike during swing phase is:
A) Hip flexor tightness
B) Leg length discrepancy
C) Weak quadriceps
D) Excessive pelvic rotation

B) Leg length discrepancy

"Extension thrust" in the knee during gait refers to:
A) Sudden knee flexion after heel strike
B) Knee locking into extension after initial contact
C) Knee hyperflexion during swing phase
D) Varus deformity during stance

B) Knee locking into extension after initial contact

The Movement Science Gait Analysis Form adds which of the following features not found in Rancho Los Amigos form?
A) Phases of gait cycle
B) Body segment observations
C) Ankle rockers and double limb support parameters
D) Standardized gait terminology

C) Ankle rockers and double limb support parameters

Impaired forward propulsion in gait would most likely affect which phase?
A) Initial contact
B) Mid-stance
C) Pre-swing
D) Terminal swing

C) Pre-swing

Antalgic gait is characterized by:
A) High stepping to clear the foot due to foot drop
B) Circumduction of the leg during swing phase
C) Avoidance of weight bearing on the painful limb
D) Walking on toes due to tight calf muscles

C) Avoidance of weight bearing on the painful limb

Circumduction gait often results from:
A) Tightness of gastrocnemius and soleus
B) Lack of ankle dorsiflexion
C) Difficulty flexing the knee
D) Painful heel strike

C) Difficulty flexing the knee

Steppage gait involves:
A) Walking on the forefoot throughout stance
B) High stepping to compensate for lack of ankle dorsiflexion
C) Excessive lateral trunk lean
D) Decreased step length on the non-affected side

B) High stepping to compensate for lack of ankle dorsiflexion

Toe walking gait is commonly caused by:
A) Weak gluteus medius
B) Tightness of calf muscles
C) Knee hyperextension
D) Ankle inversion deformity

B) Tightness of calf muscles