STANDING BALANCE Kate Ramadge Physiotherapist NSW PAR Day 30 th March 2007
What are: Standing balance Standing balance The ability to stand without using undue muscle activity, to move about in standing, to perform a wide variety of motor tasks, and to move in and out of the standing position.
What are: Postural adjustments Postural adjustments Muscle activation patterns to control of the motion of several body segments relative to each other, to ensure the upcoming movement does not destabilise the body’s equilibrium.
Contributors to PA’s Vision Vision Vestibular system Vestibular system Postural adjustments Postural adjustments - strength - timing of muscle activity - co-ordination of multiple muscles Proprioception Proprioception
Postural Adjustments: Task & Context Specificity Cordo & Nashner (1982) A. A.Person pulls on handle: Gastrocs Hamstrings Biceps last Anticipation Internally generated B. Handle is pulled: Gastrocs Biceps No anticipation Externally imposed C. Handle is pulled and trunk supported: Biceps only Leg muscles not required as postural support D. Handle and floor are pulled: Biceps delayed
Postural Adjustments: Essential features Context specific Context specific Modified by task being performed Modified by task being performed Adaptive not reflex behaviour Adaptive not reflex behaviour Muscle actions change with alterations in base of support Muscle actions change with alterations in base of support Anticipatory: muscle activation occurs in anticipation of changes in centre of mass Anticipatory: muscle activation occurs in anticipation of changes in centre of mass Vision over-rides proprioception
Vision Over-rides Proprioception A. A.Wall moves away from person B. B.Person perceives this as falling backwards C. Person falls forward to compensate Lee and Aronson (1974)
Training Postural Adjustments Train specific tasks eg reaching in sitting, standing Patients need to learn which muscles to activate in anticipation of a change in COG Need to train specific muscle actions for specific tasks
Training Postural Adjustments Patients need to practise in safety but with the opportunity challenge their postural adjustments Eg. Standing next to a wall without hand support instead of holding onto parallel bars support instead of holding onto parallel bars Postural adjustments occur in the joints adjacent to support surfaces (Slijper & Latash, 2000) (So, when should we issue a frame?)
References Barclay-Goddard R, Stevenson T, Poluha W, Moffatt M, Tabak S (2004) Force platform feedback for standing balance training after stroke. Cochrane Database of Systematic Reviews, Issue 4. Barclay-Goddard R, Stevenson T, Poluha W, Moffatt M, Tabak S (2004) Force platform feedback for standing balance training after stroke. Cochrane Database of Systematic Reviews, Issue 4. Cheng RJ, Chen Jj, Su FC (2001) Vestibular system in performance of standing balance of children and young adults under altered sensory conditions. Percept Motor Skills, 92 (3), Cheng RJ, Chen Jj, Su FC (2001) Vestibular system in performance of standing balance of children and young adults under altered sensory conditions. Percept Motor Skills, 92 (3), Cordo & Nashner (1982) Cordo & Nashner (1982) Diener HC & Dichgans J (1992) Review: Pathophysiology of cerebellar ataxia. Movement Disorders, 7, Diener HC & Dichgans J (1992) Review: Pathophysiology of cerebellar ataxia. Movement Disorders, 7, Haas G, Diener HC, Bacher M & Dichgans J (1986) Development of postural control in children: short-, medium-, and long latency EMG responses of leg muscles after perturbation of stance.Experimental Brain Research, 64(1), Haas G, Diener HC, Bacher M & Dichgans J (1986) Development of postural control in children: short-, medium-, and long latency EMG responses of leg muscles after perturbation of stance.Experimental Brain Research, 64(1), Clinical Guidelines for Stroke Rehabilitation and Recovery (2006) National Stroke Foundation Clinical Guidelines for Stroke Rehabilitation and Recovery (2006) National Stroke Foundation Slijper H & Latash M (2000) The effects of instability and additional hand support on anticipatory postural adjustments in leg, trunk, and arm muscles during standing. Exp. Brain Research, 135, Slijper H & Latash M (2000) The effects of instability and additional hand support on anticipatory postural adjustments in leg, trunk, and arm muscles during standing. Exp. Brain Research, 135, Woollacott M, Inglin B & Manchester D (1988) Response preparation and posture control. Annuals of the NYAoS, 515 (1), pp Woollacott M, Inglin B & Manchester D (1988) Response preparation and posture control. Annuals of the NYAoS, 515 (1), pp