title: The validity and reliability of motion analysis in patellar tendon reflex assessment.
abstract: BACKGROUND
  The deep tendon reflex assessments that are essential to the accurate diagnosis of neurological or neuromuscular disorders are conducted subjectively in clinical neurology. Our aim was to assess deep tendon reflexes objectively with a new reflex quantification method.
  
  
  RESULTS
  The present study used a motion analysis technique to collect quantitative measurements for both the input and output of normal patellar tendon reflex. Reflex responses were measured as knee angles. The patellar tendon reflexes of 100 healthy subjects were examined using 6 levels of tendon taps, where all the assessments were captured using motion capture system. A linear relationship was found between the experimental maximum tapping velocity and tapping angle (coefficient of determination = 0.989), which was consistent with the theoretical values. Tapping velocities were predictable according to tapping angles. The findings proved the reproducibility of tapping method in producing consistent input. The reflex amplitude was consistent between two randomly assigned groups, and linearly proportionate to the tapping velocity.
  
  
  CONCLUSIONS
  The findings on reflex amplitude indicate that motion analysis is a valid and reliable method of assessing and measuring deep tendon reflexes.
authors: Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia. laikuan_tam@hotmail.com
authors: Lai Kuan
authors: LK
authors: Tham
authors: Noor Azuan
authors: NA
authors: Abu Osman
authors: Wan Abu Bakar
authors: WA
authors: Wan Abas
authors: Kheng Seang
authors: KS
authors: Lim
mesh_terms: D006801:Humans; D009038:Motion; D017847:Patellar Ligament / Q000502:physiology*; D012016:Reference Values