Neuromuscular Score at 3 Months (NMS-3) of Hajnal et al for Predicting Developmental Abnormalities at 1 Year

 

Examination: Detailed neurologic and developmental assessment at 3 months

 

Inclusion criteria - one or more of the following:

(1) umbilical cord pH < 7.1

(2) base excess < -10

(3) Apgar at 5 minutes <= 5

(4) neonatal encephalopathy

 

Exclusion criteria - one or more of the following:

(1) gestational age < 36 weeks

(2) intrauterine or perinatal infection

(3) congenital anomalies

(4) hereditary metabolic disorder

 

Parameters:

(1) tone and reflexes

(2) muscular power in trunk and extremities

(3) cranial nerve disorder (other than isolated esophoria or exophoria)

(4) spastic quadriparesis

Tone and Reflexes	Power	Cranial Nerve	Spastic QP	Score
normal	normal	normal	absent	0
mild abnormality in tone or reflexes	normal	normal	absent	1
mild abnormality in both tone and reflexes	normal	normal	absent	2
abnormality in one or both	abnormal	normal	absent	3
variable	variable	abnormal	absent	4
NA	NA	NA	present	5

 

where:

• For score 4 there is an abnormality in tone, reflexes and/or power.

• There are several gaps in various combinations of the findings (cranial nerve abnormality without muscle dysfunction, abnormal power without tone or reflex problem, etc.)

 

Interpretation:

• The risk of developmental abnormalities at 1 year increased with the NMS.

• The presence of neonatal seizures was associated with increased risk of developmental abnormalities at 1 year.

 

NMS-3	Probability of Abnormal Neurologic Outcome at 1 Year
0	13%
1	54%
2	35%
3	80%
4	75%
5	100%

 

Performance:

• The numbers of infants studied was relatively small. Some of the irregularity in the data may stabilize with higher numbers. For example, (1) groups 1 and 2 and (2) groups 3 and 4 seem to cluster.

• The combination of neonatal seizures and an NMS-3 >= 3 had the best sensitivity (65%) and specificity (96%) for predicting developmental abnormalities at 1 year.