Lab Objectives - Exam 1

Know common devices used to measure PROM

• Goniometers

• Tape

• Inclinometers

  • Bubble

  • Digital

• CROM & BROM

• Athrodial protractors

Goniometers

• Plastic, steel, gravity dependent, cheap

  • They use weighted pointer

• MOST COMMONLY USED

  • Measures almost any joint

• Alignment is key

  • Stationary arm, moveable arm, fulcrum

• Read the beginning and end ROM (represents angle created by proximal and distal bones of joint)

  • May lack good criterion-related validity but excellent reliability

  • Intra-rater

  • Peripherial joints

• No difference in small vs large

Tape

• C7 to S1

• Schober technique

  • Lumbrosacral junction

  • 10 cm above

  • .90 Correlation coefficient with roentgenograms

• Modified Schober Technique

  • Lumbrosacral junction

  • 10 cm above

  • 5 cm below

  • .90 Correlation coefficient with roentgenograms

Inclinometer

• Accurately measures ROM

• Bubble and digital

  • Fast & small

  • Repeatable, measuring all joints including composite movement of multiple joints

  • Active and passive measurements made by one person

• More expensive

CROM (cervical)/BROM (back)

• Intra-rater .75 to .91

• Inter-rater .41 to .88

• Measures forward head/ back ROM

Arthodial protractors

• Uncommon

• Measures device for joint flexibility

• Enables quick and accurate testing of ROM in all major joints

• Transparent heavy gauge aircraft plexiglass

• Large easy to read red and blue degree markings

Accurately measure PROM

• Align fulcrum with joint

  • Stationary arm parallel to proximal segment

  • Movable arm along distal segment

• Stabilize and move passively (outside force, no voluntary muscle contraction, quantity of the motion, quality of endfeel)

  • Manually

  • Mechanical (CPM)

Identify procedures to improve reliability

• Use preferred position and stabilize proximal joint component

  • Explain and demonstrate the desired motion to your patient

• Move joint passively to complete ROM

  • Determine end-feel and make a clinical estimate on ROM

• Palpate appropriate bony landmarks

• Align goniometer’s SA and MA with landmarks

  • Determine axis of motion

• Read and record measurement

  • Compare to opposite side

  • Re-measure at the same time of day when your patient returns for their follow-up visit

  • Successive measurements should be taken by same examiner (same force for end-feel)

  • Inexperienced examiners should take several measurements

Know how to document goniometric measurements

• Be specific and objective

  • Conicise

• Be familar with what is acceptable at clinic

  • Open-minded for differing opinions

• DO NOT USE WITHIN NORMAL LIMITS (age appropriate norms)

  • Relate to well-known test

• Record beginning and ending position using 0-180 degree notation method (use table)

• Do not use total joint ROM

Accurately perform isolated MMT of UE/LE/trunk

• Follow standard positions, stabilize proximal, apply resistance in line with muscle action

Accurately assign a strength grade using the Lynch/Modified Lovett scale

• Grade 0–1: No contraction/trace

• Grade 2: Movement in gravity-eliminated

• Grade 3: Movement against gravity

• Grade 4–5: Movement against gravity + resistance

Identify/eliminate substitutions

Example: During sit-ups, moving arms changes moment arms (shorter → easier, longer → harder). Substitutions change torque demand.

Apply alternate grading scales (calf, hand, trunk)

• Trunk: Lawn Chair sit-up progression grading

• Calf: Heel raise reps (noted as functional testing in lab discussions)

• Hand: Grip/pinch dynamometer (noted in muscle testing alternatives)

Explain basic concepts of osteokinematics

• Planes of motion→ axis of rotation→ movements

  • Sagittal plane→ mediolateral axis → flex/ext

  • Frontal plane→ anteroposterior axis→ abd/add

  • Horizontal plane→ vertical axis→ int/ext rotation

Glenohumeral joint

• Number of axis = 3

• Orientation of axis = mediolateral, vertical, anteroposterior

• Location passing through = humeral head

• Plane of motion = sagittal, horizontal, sagittal

• Movement = flex/ext

Humeroulnar joint

• Number of axis = 1

• Orientation of axis = mediolateral

• Location passing through = medial and lateral epicondyles of humerus

• Plane of motion = sagittal

• Movement = flex/ext

Radiocarpal joint

• Number of axis = 2

• Orientation of axis = mediolateral, anteroposterior

• Location passing through = head of capitate (may be scaphoid)

• Plane of motion = sagittal, frontal

• Movement = flex/ext, ulnar/radial deviation

Hip joint

• Number of axis = 3

• Orientation of axis = mediolateral, vertical, anteroposterior

• Location passing through = femoral head

• Plane of motion = sagittal, horizontal, frontal

• Movement = flex/ext, int/ext rotation, abd/add

Tibiofemoral joint

• Number of axis = 2

• Orientation of axis = mediolateral (slight deviation), vertical

• Location passing through = lateral and medial epicondyles of femur, along the tibia

• Plane of motion = sagittal, horizontal

• Movement = flex/ext, int/ext rotation

Talocrual joint

• Number of axis = 1

• Orientation of axis = mediolateral (slight deviation)

• Location passing through = talus, or medial and lateral malleoli

• Plane of motion = sagittal

• Movement = dorsiflexion/plantarflexion (pronation/supination of subtalar joint)

Analyze open vs closed chain

• Standing from seated position & straighten the leg while sitting = knee extension

  • Open chain = straighten leg while sititng

  • Close chain = stand up from a seated position

Explain arthrokinematics and convex-concave rule

• Convex on concave = roll & glide opposite

• Concave on convex = roll & glide same

• Examples: shoulder (convex humeral head on concave glenoid) vs knee (concave tibia on convex femur).

Convex-on-concave movement

• Relatively fixed = concave

• Relatively mobile = convex

• Movement (roll & glide) = opposite

Concave-on-convex movement

• Relatively fixed = convex

• Relatively mobile = concave

• Movement (roll & glide) = same

Glenohumeral joint in open chain movement

• Fixed concave = glenoid fossa

• Mobile convex = humeral head

• Convex-on-concave

Humeroulnar joint in open chain movement

• Fixed convex = trochlea on humerus

• Mobile concave = trochlea notch

• Concave-on-convex

Wrist radiocarpal joint in open chain movement

• Fixed concave = radius distal end

• Mobile convex = carpal bones

• Convex-on-cave

Hip in open chain movement

• Fixed concave = acetabular fossa

• Mobile convex = head of the femur

• Convex-on-concave

Tibiofemoral joint in open chain movement

• Fixed convex = femoral condyles

• Mobile concave = tibial condyles

• Concave-on-convex

Talocrural joint in open chain movement

• Fixed concave = distal end of the tibia and both malleoli

• Mobile convex = trochlea and sides of the talus

• Convex-on-concave

Glenohumeral flexion

• Roll = superior

• Slide = inferior (or spin)

Glenohumeral extension

• Roll = inferior

• Slide = superior (spin)

Glenohumeral internal rotation

• Roll = anterior

• Slide = posterior

Glenohumeral external rotation

• Roll = posterior

• Slide = anterior

Glenohumeral abduction

Roll = superior

Slide = inferior

Glenohumeral adduction

• Roll = inferior

• Slide = superior

Humeroulnar flexion

• Roll = anterior

• Slide = anterior

Humeroulnar extension

• Roll = posterior

• Slide = posterior

Radiocarpal flexion

• Roll = anterior

• Slide = posterior

Radiocarpal extension

• Roll = posterior

• Slide = anterior

Radiocarpal radial deviation

• Roll = lateral

• Slide = medial

Radiocarpal ulnar deviation

• Roll = medial

• Slide = lateral

External torque with load (external force & moment arm)

Torque = Force × Moment Arm; gravity acts as external force, perpendicular distance as moment arm

External torque with effort (internal forces & moment arms)

• Internal torque = muscle force × internal moment arm; must balance external torque.

  • Largest external torque, due to longest external moment arm

  • Internal moment arm does not change among sit-ups

The component vector acting along the parallel line will result in a distraction/compression force (blue vector). How to differentiate whether this component vector will be distraction or compression force?

a. When the arrow head is pointing toward the hand, this component vector is pulling the forearm “away” from the joint center (i.e. AOR) distraction (example: C)
b. When the arrow head is pointing toward the joint center, this
component vector is pulling the forearm “toward” the joint center (i.e. AOR)  compression (example: A)

The component vector acting along the perpendicular line will result in a
rotary/shear force. (orange vector)

Calculate muscle force using torque equilibrium

Equation: Muscle Force = (External Force × External MA) ÷ Internal MA