Georgia Fisher, University of Technology Sydney, Sydney, Australia
Participant of the Young Stroke Physicians and Researchers Research Design Workshop for Studies in Development – ESOC 2019
The advent of clot busting medications and endovascular clot retrieval has revolutionised acute stroke management in recent years, resulting in large improvements in patient prognosis. This improved prognosis impacts all areas of stroke care, including rehabilitation, where rehabilitation physicians are now encountering more patients who rapidly achieve their mobility goals and need assistance in regaining control of subtler, yet still functionally essential impairments, such as Unilateral Neglect (UN).
UN is characterised by the failure to report, respond, or orient to novel or meaningful stimuli that are presented on the side opposite to the brain lesion 1. UN can affect up to 80% of stroke patients 2, and any combination of three hemispaces (Fig 1), and three modalities (Fig 2) 3,4. Most importantly, having UN results in poorer functional outcomes, longer hospital stays and a reduced likelihood of returning home on discharge 5,6. To improve prognosis of patients with UN, developing potential treatment strategies is crucial, but first we need to have reliable assessment of UN. Unfortunately, clinicians are currently faced with ~28 different standardised tests to identify UN, most of which fail to capture more than one component of the condition 7. This makes it difficult to detect the true spectrum of impairments present in UN, and thus treatment strategies are limited in their success.
What is the limitation of the current approach in assessing UN? The deficits in UN are mediated in part by proprioception, which is a set of sensorimotor processes that are a major contributor to our ability to control movement and thus everyday function and when measured, are worse in people with UN8,9. Sensorimotor assessment is however usually generalised to separate impairments in strength, sensation, and vision, but not specifically to proprioception 10. This is not entirely surprising, as there is currently a huge disparity between the theory and clinical practice of proprioceptive assessment in stroke affected populations11. In theory, we know that proprioception encompasses multiple processes including the ability to detect and judge magnitudes of movement and forces, time muscular contractions, and develop an internal representation of your body12. However, traditional clinical assessment of proprioception usually assesses only movement detection, using tests that are insensitive to change and poorly correlated to patient functional outcomes 13-15. Thus, this essential sensorimotor process often goes unassessed, and untreated in stroke populations.
To address this evidence-practice gap, specific to UN populations, our research team at the University of Technology Sydney aim to develop a comprehensive sensorimotor assessment tool to identify UN and associated impairments with high precision, portability, and ease of use in the clinic. In doing so, a more complete understanding of the deficits present in UN will be possible, ultimately providing the foundation for treatments that target them. Instead of a one size fits all treatment strategy, we envisage the development of a battery of treatments from which a tailored selection can be made to meet patient specific needs. Then, patients with UN after stroke will no longer be faced with the prospect of a markedly worse functional prognosis and a half-empty world. Instead, they can have the hope of a successful rehabilitation, and a reintegration into everyday life after stroke.
If you are interested in joining us in our work on improving assessment in UN, please email Dr David Kennedy at David.firstname.lastname@example.org for further information.
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- Azouvi P. The ecological assessment of unilateral neglect. Ann Phys Rehabil Med. 2017;60(3):186-190.
- Heilman KM, Valenstein E, Watson RT. The what and how of neglect. Neuropsychol Rehabil. 1994;4(2):133-139.
- Robertson IH, & Halligan, P. W. Spatial neglect: A clinical handbook for diagnosis and treatment. Hove, East Sussex: Psychology Press; 1999.
- Di Monaco M, Schintu S, Dotta M, Barba S, Tappero R, Gindri P. Severity of Unilateral Spatial Neglect Is an Independent Predictor of Functional Outcome After Acute Inpatient Rehabilitation in Individuals With Right Hemispheric Stroke. Arch Phys Med Rehabil. 2011;92(8):1250-1256.
- Jehkonen M, Laihosalo M, Kettunen JE. Impact of neglect on functional outcome after stroke – A review of methodological issues and recent research findings. Restor Neurol Neurosci. 2006;24(4-6):209-215.
- Menon A, Korner-Bitensky N. Evaluating Unilateral Spatial Neglect Post Stroke: Working Your Way Through the Maze of Assessment Choices. Top Stroke Rehabil. 2004;11(3):41-66.
- Proske U, Gandevia SC. Kinesthetic Senses. Comprehensive Physiology. 2018;8(3):1157-1183.
- Meyer S, De Bruyn N, Lafosse C, et al. Somatosensory Impairments in the Upper Limb Poststroke: Distribution and Association With Motor Function and Visuospatial Neglect. Neurorehabil Neural Repair. 2016;30(8):731-742.
- Rengachary J, He BJ, Shulman GL, Corbetta M. A Behavioral Analysis of Spatial Neglect and its Recovery After Stroke. Front Hum Neurosci. 2011;5:29.
- Hillier S, Immink M, Thewlis D. Assessing Proprioception: A Systematic Review of Possibilities. Neurorehabil Neural Repair. 2015;29(10):933-949.
- Proske U, Gandevia SC. The proprioceptive senses: their roles in signaling body shape, body position and movement, and muscle force. Physiol Rev. 2012;92(4):1651.
- Winward CE, Halligan PW, Wade DT. The Rivermead Assessment of Somatosensory Performance (RASP): standardization and reliability data. Clin Rehabil. 2002;16(5):523-533.
- Stolk-Hornsveld F, Crow JL, Hendriks EP, van der Baan R, Harmeling-van der Wel BC. The Erasmus MC modifications to the (revised) Nottingham Sensory Assessment: a reliable somatosensory assessment measure for patients with intracranial disorders. Clin Rehabil. 2006;20(2):160-172.
- Meyer S, Karttunen AH, Thijs V, Feys H, Verheyden G. How Do Somatosensory Deficits in the Arm and Hand Relate to Upper Limb Impairment, Activity, and Participation Problems After Stroke? A Systematic Review. Phys Ther. 2014;94(9):1220-1231.