Examination of Postural and Muscle Tone - Infant

Question 1

muscle tone

Answer 1

• resistance of m. to passive elongation or stretch when an individual attempts to maintain m. relaxation or degree of residual contraction in resting m. (O’Sullivan)
• readiness of m. to respond to gravity (Movement Assessment of Infants)

Question 2

palpation/consistency (O’S)

Answer 2

• assess consistency, firmness, and turgor
• hypotonic - soft and flabby
• hypertonic - taut and hard

Question 3

palpation/consistency (MAI)

Answer 3

• assess in supine and prone
• gastroc/soleus, triceps, biceps
• 1 = m. feels soft; little resistance to pressure
• 3 = m. feels sturdy, but some yielding to pressure (normal)
• 5 = m. feels hard like a rock; little yielding to pressure

Question 4

extensibility (O’S)

Answer 4

• assess via repeated passive motion, increasing speed of motion
• 0 = no response
• 1+ = decreased response (hypotonia)
• 2+ = normal response
• 3+ = exaggerated response (mild to mod. hypertonia)
• 4+ = sustained response (severe hypotonia)

Question 5

extensibility (MAI)

Answer 5

• in supine assess hid ADD, ankle PF, shoulder EXT
• 1 = no resistance
• 2 = slight resistance throughout ROM
• 3 = normal graded resistance through ROM
• 4 = greater than normal resistance, full ROM only during slow movement
• 5 = strong resistance, prevents movement through full ROM

Question 6

passivity (O’S)

Answer 6

pendulum test: position infant in supine with knee flexed over edge of table, fully extend knee, let go and observe amount and duration of swing

Question 7

passivity (MAI)

Answer 7

• supine or sitting
• hold either LE or UE just proximal to the wrist or ankle joint and shake distal part of extremity quickly
• 1 = extremity does not tighten at wrist or ankle
• 2 = hand or foot flap for many excursions, but eventually tightens
• 3 = extremity tightens at wrist or ankle after a few excursions
• 4 = extremity stiff initially, but some flapping occurs
• 5 = extremity is stiff at wrist or ankle, hand or foot does not flap

Question 8

postural tone

Answer 8

• pattern of m. tension that exists throughout the body affecting m. groups OR
• m. activation against supporting surface

Question 9

signs of hypotonia

Answer 9

• excessive collapse of body segments
• loss of postural alignments
• inability to sustain a posture against gravity

Question 10

signs of hypertonia

Answer 10

• distal fixing (toe curling, hands fisting)
• difficulty moving a body segment through a range
• asymmetric posture

Question 11

grading of postural tone (MAI)

Answer 11

• supine or prone
• 1 = hypotonia: child lies flat against support surface, unable to maintain antigravity posture, movement infrequent and weak
• 3 = normal: child shows variety of resting positions, moves away from surface, assumes age appropriate antigravity postures and easily maintains them, frequent movements with varied combinations of extremities
• 5 = hypertonia: child is pulled strongly toward an extended and asymmetrical posture, pulled away from antigravity postures, infrequent and slow and stiff movement