ROBOTIC ASSESSMENT OF POST-CALL SENSORIMOTOR AND COGNITIVE FUNCTION IN ORTHOPAEDIC SURGERY RESIDENTS

Sleep deprivation can negatively affect cognitive reasoning, complex decision-making, and motor function; all of which are necessary skills for surgical residents. Despite this, orthopaedic surgery residents are required to work extended duty hours including 26-hour overnight call shifts and robust evidence regarding the effects of sleep deprivation on surgical residents is lacking. The Kinesiological Instrument for Normal and Altered Reaching Movements (KINARM) is a robotic exoskeleton used to measure disturbances in sensorimotor function, cognitive reasoning, and proprioception in patients with stroke, traumatic brain injuries, and neurodegenerative diseases. The aim of this study was to determine if resident performance using KINARM standard tests (KSTs), a surrogate measure of skills required to perform surgery and make critical decisions related to surgery, is adversely affected in a post-call versus a pre-call state. This is a prospective cohort study involving orthopaedic surgery residents at a Level One Trauma Centre. Following informed consent, residents wore a portable sleep-tracking device (WHOOP 3.0) for 14 days, which collected information regarding sleep quality and quantity. Residents were assessed using six KSTs at five time points: orientation (to mitigate learning effect), pre-call shift 1 (baseline data), post-call shift 1, post-call shift 2, and post-call shift 3. The KSTs included tasks designed to measure accuracy, proprioception, cognition, motor function, and visuospatial working memory. Self-reported caffeine intake, call volume, quality of life, and satisfaction were also measured. All tests were examined based on their task score, which is a normalized global measure of task performance, and presented as a 1-tailed Z score. A total of 10 residents participated in the study. The mean age was 28 (SD=1.2) years, five (50%) participants were female, and all were right-handed. The mean total minutes slept while on call was 189 (SD=134) minutes or 3hours and 9minutes versus 416 (SD=118) minutes or 6hours and 56minutes while not on call (Figure 1). The mean caffeine intake in the 24hours prior to assessment was 220.6mg (SD=204.9mg) or the equivalent of a medium drip coffee. With the exception of one task, unadjusted for multiple comparisons, there were no statistically significant differences between pre-call and post-call performance on the KSTs. However, on several KSTS, some individuals tested outside of the population norms in a post-call state. For example, the “Object Hit and Avoid” KST, which measures cognition, accuracy and speed, demonstrated that two residents tested outside of population norms in a post-call state (Figure 2). The KINARM robot has been used clinically to assess disturbances of motor control in stroke patients; however, the application of its use in post-call surgical residents is novel. This highly sensitive test found minimal differences in multiple measures of accuracy, proprioception, cognition, motor function, and visuospatial working memory of post-call residents. Further analysis is ongoing to evaluate caffeine intake, consult volume and sleep on the KST results, quality of life measures, and educational satisfaction while working 26-hour in-house call. Overall, this work will help inform the discussion regarding fatigue risk management tactics in orthopaedic surgery training programs. For any figures or tables, please contact the authors directly.