title: Development of a new assessment tool for cervical myelopathy using hand-tracking sensor: Part 1: validity and reliability.
abstract: To assess the reliability and validity of a hand motion sensor, Leap Motion Controller (LMC), in the 15-s hand grip-and-release test, as compared against human inspection of an external digital camera recording.
  
  
  
  Fifty healthy participants were asked to fully grip-and-release their dominant hand as rapidly as possible for two trials with a 10-min rest in-between, while wearing a non-metal wrist splint. Each test lasted for 15 s, and a digital camera was used to film the anterolateral side of the hand on the first test. Three assessors counted the frequency of grip-and-release (G-R) cycles independently and in a blinded fashion. The average mean of the three was compared with that measured by LMC using the Bland-Altman method. Test-retest reliability was examined by comparing the two 15-s tests.
  
  
  
  The mean number of G-R cycles recorded was: 47.8 ± 6.4 (test 1, video observer); 47.7 ± 6.5 (test 1, LMC); and 50.2 ± 6.5 (test 2, LMC). Bland-Altman indicated good agreement, with a low bias (0.15 cycles) and narrow limits of agreement. The ICC showed high inter-rater agreement and the coefficient of repeatability for the number of cycles was ±5.393, with a mean bias of 3.63.
  
  
  
  LMC appears to be valid and reliable in the 15-s grip-and-release test. This serves as a first step towards the development of an objective myelopathy assessment device and platform for the assessment of neuromotor hand function in general. Further assessment in a clinical setting and to gauge healthy benchmark values is warranted.
authors.affiliation: Academic Orthopaedics, Trauma and Sports Medicine, Queen's Medical Centre, The University of Nottingham, Nottingham, NG7 2UH, UK.
authors.forename: M Abdulhadi
authors.identifier: 0000-0002-1097-7793
authors.initials: MA
authors.lastname: Alagha
authors.affiliation: Medical, Veterinary and Life Sciences College, University of Glasgow, Dental Hospital, Glasgow, G2 3JZ, UK.
authors.forename: Mahmoud A
authors.initials: MA
authors.lastname: Alagha
authors.affiliation: Centre for Spinal Studies and Surgery, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
authors.forename: Eleanor
authors.initials: E
authors.lastname: Dunstan
authors.affiliation: VRmed Ltd., Rosewood House, Radcliffe on Trent, Nottingham, NG12 2BQ, UK.
authors.forename: Olaf
authors.initials: O
authors.lastname: Sperwer
authors.affiliation: School of Sport and Exercise Science, University of Lincoln, Lincoln, LN6 7TS, UK.
authors.forename: Kate A
authors.initials: KA
authors.lastname: Timmins
authors.affiliation: Centre for Spinal Studies and Surgery, Queen's Medical Centre, Nottingham, NG7 2UH, UK. bronek.boszczyk@nuh.nhs.uk.
authors.forename: Bronek M
authors.initials: BM
authors.lastname: Boszczyk
mesh_terms: D000328:Adult; D002574:Cervical Vertebrae / Q000503:physiopathology*; D003936:Diagnosis, Computer-Assisted; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D009460:Neurologic Examination / Q000295:instrumentation*; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013117:Spinal Cord Compression / Q000175:diagnosis* / Q000503:physiopathology; D000076142:Virtual Reality; D055815:Young Adult
keywords: Cervical myelopathy; Grip and release test; Leap motion; Reliability; Validity; Virtual reality