Mary P Galea Department of Medicine (Royal Melbourne Hospital)

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1 Mary P Galea Department of Medicine (Royal Melbourne Hospital)

2 SCI: An extreme example of forced inactivity Immediate and severe loss of sensory and motor function Muscle atrophy Poor circulation Disruption of calcium and phosphate metabolism: loss of bone Immunosuppression: vulnerability to infections Exacerbation of neurological dysfunction due to inactivity Significant secondary complications: pressure ulcers and fractures Metabolic profile similar to that of premature aging

3 Muscle changes post-sci Healthy Control SCI 6 weeks post-sci Transformation from slow, fatigue-resistant to fast, fatigable muscle Reduced connective tissue extensibility Intramuscular fat accumulation Gorgey & Dudley, Spinal Cord 2007; 45:

4 Reduced trabecular bone mineral density after SCI Femur Tibia Lines indicate mean ± 2 standard deviations of a reference population of able-bodied subjects. o = paraplegic + = tetraplegic Eser et al. Bone 2004; 34:

5 Loss of bone after SCI Healthy SCI Accelerated bone loss due to increased resorption and reduced formation Intracortical remodeling produces porosity (thinning from inside )

6 Effects of immobilisation Passive stretching Limits functional recovery Prevents regaining of forelimb hindlimb coordination Immobility Significantly hinders functional recovery acutely Potentially limits the responsiveness to retraining efforts initiated at later time points. Caudle et al. Neurorehabil Neural Repair2011; 25:

7 Effects of exercise on the nervous system Maintenance of the nervous system and target organs Prevention of secondary complications Improved general health and prevention of metabolic diseases Neurological recovery - Reorganisation of spared pathways

8 Functional electrical stimulation

9 Exercise and muscle changes Pre-training After 6 months FES-cycling Image courtesy of Prisca Eser Reversal of atrophy Reversal of changes in muscle fibre type Enhanced aerobic metabolism Hybrid training (FES leg exercise plus arm exercise) has potent effects on oxygen uptake Andersen et al. Pflügers Arch 1996; 431:513 8; Davis et al. Artif Organs 2008; 32:

10 The nervous system Image from Thibodeau & Patton (eds) Anatomy & Physiology, 3 rd ed. 1996

11 The nervous system has a body! Image from Thibodeau & Patton (eds) Anatomy & Physiology, 3 rd ed. 1996

12 Peripheral processes Muscles and muscle receptors Somatosensory inputs Endo et al. Exp Neurol2008; 209:

13 Endo et al. Neuroscientist :

14 Deterioration of nervous system function below the level of injury High prevalence of spontaneous activity Decreased amplitude/absence of compound action potentials Observations consistent with denervation of skeletal muscles Lin et al. Brain 2007; 130: ; Riley et al. PM&R 2011, 3:

15 Changes in neuromuscular junction Spinal Cord Injury Aging Pre-exercise Post-exercise Valdez et al. PNAS 2010; 107: ; Burns et al J Comp Neurol 2007; 500:

16 Rehabilitation after SCI Rehabilitation after spinal cord injury (SCI) has been based on expectations regarding functional Lesion site outcomes predicted by the EphA4 -/- initial level of injury and severity of impairment strategies Wild Type and/or use assistive devices to accomplish daily tasks Lesion site Regenerating axons Recovery of function beyond this has not been expected, therefore compensation for loss of function is a key strategy People with SCI develop a new repertoire of movement New paradigm: activity-based therapies - Maintain target systems below the level of injury - Maintain optimum health and fitness No regeneration

17 SCIPA Program Theme: Exercise from acute care to the community Concerned with understanding the effects of exercise on recovery, health and well-being after spinal cord injury 4 Projects: SCIPA Hands-On: Comparison of FES-assisted exercise for the hand vs standard care SCIPA Full-On: Comparison of full body exercise vs upper body exercise SCIPA Switch-On: Comparison of FES-assisted cycling vs passive cycling early after SCI SCIPA Com: Education program for community exercise instructors

18 SCIPA Hands-On 8-weeks intervention 6 months follow-up Outcome measures Primary: Action Research Arm Test Secondary: SCIM; BMCA; QoL Kowalczewski et al. Neurorehabil Neural Repair2011; 25:412-22; Harvey et al. Trials2011; 12:14

19 SCIPA Full-On 12 weeks intervention (3 x weekly) 6 months follow-up Outcome measures Primary: ASIA Motor Score Secondary:SCIM, pain, psychological measures, quality of life and cost effectiveness Galea et al. Trials 2013;14:291

20 SCIPA Switch-On 12 weeks intervention No long-term follow-up Outcome measures Primary: Muscle cross-sectional area of thigh and calf Other: Serum biomarkers of bone and immune function Bone porosity (Victoria) ASIA Scores Body composition QoL and depression Galea et al. Trials 2015;16:7

21 SCIPA Com Garry Allison and Beatriz D Oliveira, Curtin University

22 SCIPA Com

23 Spinal cord stimulation: a step towards repair?

24 Acknowledgements Investigators Sarah Dunlop (UWA) Garry Allison (Curtin) Lisa Harvey (U Syd) Glen Davis (U Syd) Andrew Nunn (Austin) Ruth Marshall (Hampstead SA) Rick Acland (Christchurch NZ) Tim Geraghty (PAH, Qld) Iven Mareels (U Melb) Arthur Hsueh (U Melb) Program Management Melanie Hurley Su Cox Sophie Beasy PhD students Beatriz D Oliveira Allison Yates Maya Panisset Site Coordinators Austin Health Royal Rehabilitation Centre Prince of Wales Hospital Princess Alexandra Hospital Shenton Park Rehab Centre Hampstead Rehab Centre Burwood Spinal Injuries Unit

25 Acknowledgements Premier s Science & Research Fund, SA The