Introduction:

Recognizing and measuring defects in posture such as lumbar lordosis can point towards a range of medical diagnoses.

The examination of lumbar lordosis may be accomplished through visual observation or by using a number of measurement instruments, most typically a bubble inclinometer or goniometer.

The introduction of mobile devices with inbuilt accelerometers potentially offers a simple method of assessing posture.

Objective:

To investigate the reliability, minimal detectable change (MDC90) and concurrent validity of a gravity-based bubble inclinometer (inclinometer) and iPhone application for measuring standing lumbar lordosis.

Study Conclusion:

Both the inclinometer and iPhone application possess good interrater reliability, intrarater reliability and concurrent validity for measuring standing lumbar lordosis. This investigation provides preliminary evidence to suggest that smart phone applications may offer clinical utility comparable to inclinometry for quantifying standing lumbar lordosis. Clinicians should recognize potential individual differences when using these devices interchangeably.

Commentary:

This article contributes to a growing body of evidence which identifies mobile devices as potentially useful tools to accurately assess and measure biomechanical variables such as lumbar lordosis. The accelerometers and gyroscopes within modern mobile devices can potentially be tested and researched in a range of clinical situations. This study outlines groundwork for further research in this area in order to evaluate the interchangeability of smart phone applications with other commonly used measurement tools. There are also implications for developing nations where access to suitable medical equipment may be limited.

Methods:

  • Two investigators used both an inclinometer and an iPhone 4  with an inclinometer application to measure lumbar lordosis of 30 asymptomatic participants (12 men and 18 women)
  • The iPhone 4 used the iHandy level application
  • Measurements of lumbar lordosis at T12 and S1 were repeated twice by each investigator with both an iPhone and bubble meter

Results:

  • Good interrater reliability was found with both the gravity-based bubble inclinometer and the iPhone with ICC values of 0.90 and 0.96.
  • Good intrarater reliability was also found with both the gravity-based bubble inclinometer and the iPhone with ICC values of 0.85 and 0.81.
  • The mean difference between the inclinometer and the iPhone was -0.8 degrees with differences (95% limits of agreement) ranging from the iPhone being 8.8 degrees greater to 7.5 degrees less than the bubble inclinometer.

Article Name: The reliability, minimal detectable change and concurrent validity of a gravity-based bubble inclinometer and iphone application for measuring standing lumbar lordosis
Authors: Paul A. Salamh, and Morey Kolber
Journal Published: Physiother Theory Pract
Date Published: Received: 2 November 2012 / Accepted: 21 March 2013 / Published online: 17 July 2013
PubMed Link: http://www.ncbi.nlm.nih.gov/pubmed/23862655