Validity and reliability of digital inclinometer for assessment of joint position sense in patients with knee osteoarthritis

Abstract

Background: Knee osteoarthritis is considered the most common chronic degenerative joint disease, impairing the quality of life and function among older adults. Impaired somatosensory and proprioceptive function have been linked to Knee osteoarthritis. Objective: To examine the validity and reliability of digital inclinometer in measuring knee joint position sense in individuals with knee osteoarthritis. Design, materials and methods: Thirty male and female patients diagnosed as knee osteoarthritis participated in this cross-sectional study (their mean of the age was 56.33 ± 4.41; weight was 85.9 ± 12.96; and height was 161.16 ± 9.39 respectively. All participants were examined for active knee repositioning test using digital inclinometer & isokinetic dynamometer to determine absolute angular error for target angle 30 degrees (open kinetic chain). Results: The results indicated that absolute angular error by digital inclinometer was good positive significantly associated with absolute angular error by isokinetic (p-value=0.001). The inter-class reliability showed that there was a low reliability of absolute angular error by digital inclinometer (with ICC=0.467 and P-value=0.004). The intra-class reliability showed that there was a high reliability of absolute angular error by digital inclinometer (with ICC=0.691 and P-value=0.0001). Conclusion: Digital inclinometer is a valid alternative for isokinetic dynamometer in measuring active knee joint position sense in individuals with knee osteoarthritis at target angle 30˚ of knee flexion. However, there were high intra-class reliability and low inter-class reliability at target angle 30˚ of knee flexion.