Segmental Assessment of Trunk Control (SATCo)

Original Editor - Lauren Heydenrych

Top Contributors - Lauren Heydenrych  

Objective

The objective of the Segmental Assessment of Trunk Control (SATCo) is to provide a detailed assessment of trunk control, identifying:

1. The highest segmental level at which intervention must be targeted.
2. And the optimal level of support needed by the individual.

It is an assessment tool and outcome measure that provides a "close definition of the level at which trunk control difficulties present and leads to a 'level by level' treatment to the development of trunk control" (Butler et al, 2010).

The development of the SATCo has been specifically designed as part of the Targeted Training (TT) approach. TT itself is a therapeutic strategy developed by Penny Butler and Richard Major to improve the functional abilities of children with problems of movement control through improving control of upright posture.

Intended Population

SATCo has initially been developed for infants and children with neuromotor developmental impairments.

Children as young as 4 months have been included in studies using the SATCo. There has been no maximum age given to which this test can be administered, although once an individual has gained full active trunk control, the administration of the SATCo becomes difficult to perform. This owing to the fact that children with full trunk control are often difficult to contain on the assessment bench.

Method of Use

SATCo is performed in the clinical setting or at home.

It examines postural control in a sitting position by a gradual reduction of support under three different conditions.

The three conditions are:

• Static control - Maintaining a neutral vertical posture with no movement.
• Active control - Maintaining a neutral vertical posture with voluntary head movements or arm movements.
• Reactive control - A recovery of the neutral vertical posture after a disturbance of balance caused by a nudge.

The support is provided at six distinct levels or segments, moving cephalo-caudally, starting at the shoulder girdle and ending without any support given.

These levels are:

Note: Reactive control is not tested at the head. Simply the static and active control.

Anatomical level	Manual support
C7	Shoulders
T1-3	Axillae
T3-7	Inferior scapulae
T7-T11	Lower ribs
T12-L3	Below ribs
L4-S5	Pelvis
Full trunk	No support

Equipment

The following equipment is needed:

• A bench, ideally height adjustable and with relevant straps for the pelvis.
• Pen and assessment form and scoring sheet.
• Toys/ objects to hold child/ infants attention.
• 2 cameras/ recording devices

Set-up

The following is a description of assessors needed and positioning required.

A minimum of two testers are required:

• One to support the trunk

• Another to a) monitor the child's posture, b)monitor the child's hand and arm position and c) provide nudges for the reactive component of SATCo.

The child to be tested wears only a nappy or shorts as the trunk need to be clearly observed.

Child's position:

• Seated on a bench. Pelvis is stabilized by support system. Feet supported (age dependent). Straps should ideally be used to ensure pelvis remains in neutral.
• Head is central with eyes looking forward. The chin is neither protracted nor retracted.
• Shoulder girdle is neither protracted nor retracted.
• Hands and arms are free from contact with own body or any external support, including a toy being held in both hands or linking hands together.
• Spinal profile should be normal for age with no joints at end of range.
• Pelvis in neutral.
• Hip and knee angles both at 90°
• Feet supported if age appropriate. Feet are left free if the child is not yet weight-bearing or if the child pushes hard on the support surface during the SATCo.

Important to remember: The head and body is to be kept in a neutral vertical posture both above and below manual support provided.

Scoring

The way in which the SATCo is delivered and scored:

Control in each segment is recorded as present (tick mark) or absent (- or x). There is no in-between.

To score in Static control, both head and trunk need to be held in neutral vertical posture for 5 seconds.

To score in Active control, neutral vertical posture needs to be held while turning head 45° and/ or reaching to both left and right.

To score in Reactive control, maintenance of neutral vertical posture or a quick return to a neutral vertical posture is required following an external pertubation (brisk nudge).

The brisk nudge in the SATCo test is large enough to perturb posture. When testing reactive control, a brisk nudge is given to 4 principle directions:

• The top of the sternum
• C7/ T1
• Left and right acromion (laterally) in turn.

A child may score static, active and reactive all on the same level/ segment, or on differing levels. The level/ segment at which control is not demonstrated is where control learning should commence.

Part in the ICF

In measuring the level of trunk control, SATCo falls within the body function measure of the International Classification of Functioning, Disability and Health (ICF). Knowing this however, can help in considering where activity and participation restrictions are likely to be.

Evidence

Reliability

Both inter-rater and intra-rater reliability are good. With a study done with both term and preterm (age corrected) infants between 4 to 9 months, the interclass correlation (ICC) scored ≥ 0.8 .

In 2010 a study done by Butler et al. found that discrepancy in inter-rater reliability was because of:

1. Failure of supporting therapist to adequately align and extend the trunk.
2. Failure of testers to recognize compensatory strategies used by infants and children.
3. Failure of raters to accurately determine level of control assessed, due to skeletal immaturity.
4. Difficulty in identifying what was loss of head control and what was habitual posturing.
5. Difficulty in identifying head posture due to cortical visual impairment (CVI).

Moderate to good correlation was also found when comparing the SATCo against other motor assessments.

Validity

Construct validity seems dependent on age and postural demands. For example, with young infants below the age of 8 months, the SATCo is not able to differentiate between preterm and term infants. The hypothesis here is that before 8 months both groups of infants have similar postural demands, being primarily reclined. It is further recommended that studies are performed with a greater sample size and over longer follow-up to verify this hypothesis.

When the SATCo was performed against the AIMS and GMFM Dimension B, high correlation was shown. In addition, the high correlation between the GMFCS and Mobility Dimension of the PEDI Mobility was able to demonstrate that SATCo reflects severity of disease as well as motor function.

Responsiveness

Good responsiveness was demonstrated in SATCo testing of infants between 4 and 9 months.

Links

Home page of Optimi - where additional information can be found on Targeted Training and additional resources: https://optimi.org.uk/sample-page/

Clinical workbook put together by Leckey describing the SATCo: https://www.leckey.com/media/3260/satco-clinical-workbook.pdf

SATCo form and scoring guidelines are found within the following article, Appendixes https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2927393/