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Chapter 3 • Functional Posture 55

but not promote the function, participation or activities they desire. Provision of postural
solutions for optimum function is therefore akin to a jigsaw puzzle; each piece is impor-
tant to build the bigger picture and to achieve a successful outcome for the person.
This chapter will first describe what is meant by the terms ‘posture’ and ‘postural con-
trol’, and which mechanisms impact on the achievement of an effective and functional
posture. It will then explain why children or adults with neurological impairment may
have difficulties with postural control. It goes on to explain what postural management
comprises and the importance of promoting postural control and a functional posture. It
discusses the important factors in the assessment process when considering a solution to
meet the needs of a person’s posture and lastly discusses two case studies to demonstrate
possible solutions for functional positioning.

What Is Posture and Postural Control?

The term posture can simply be defined as the position of the body, or of body parts, in
relation to each other and their position within space (Ham et al., 1998; Hadders-Algra,
2008). Our posture is continually changing as we shift in and out of varying symmetrical
and asymmetrical positions, to complete and move between functional tasks and activi-
ties, in response to environmental factors and to remain upright against gravity. Postural
control is the ability to remain upright, balanced and maintain control of a state of bal-
ance while performing a specific task or activity (Latash, 2008).
For an individual with fully functioning sensory, musculoskeletal and nervous sys-
tems, this level of control happens almost completely at an autonomic level, and pos-
tural adjustments and changes, on the whole, occur without any conscious reaction or
thought. However, it has been shown that there is a correlation between the complexity of
a task being performed and the increase in attention required to maintain postural control
(Reilly et al., 2008; Brauer et al., 2002).
To understand why children and adults with complex neurological disabilities have
such significant problems with their posture, we need to understand the mechanisms that
provide postural control.

The Postural Control System

There are two key functional goals of the postural control system:
First, postural orientation; the ability to maintain the active alignment of the head,
trunk and body segments with respect to gravity, the supporting surface and information
provided through visual and internal feedback systems (Horak and Macpherson, 2011).
Second, postural equilibrium/stability; the coordination of movement strategies to
stabilise the centre of body mass during both self-initiated and externally triggered
disturbances of stability such as required during a specific task or activity (Shumway-
Cook and Woollacott, 2001).