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Published on: February 10, 2015
The validity and reliability of noninvasive methods for measuring kyphosis
Fatemeh Azadinia1, Mojtaba Kamyab, Hamid Behtash
1*Department of Orthotic & Prosthetic, School of Rehabilitation †Department of Orthopaedic Surgery, Hazrat Rasoul Hospital ‡Department of Orthopaedic Surgery, Shafa Yahyaiian Hospital, Tehran University of Medical Sciences, Tehran §Department of Clinical Sciences, Faculty of Medicine, Kashan University of Medical sciences, Kashan, Iran.
The digital inclinometer is a valid and reliable tool for measuring thoracic kyphosis, suitable for regular screening. The flexicurve tool showed poor reliability for assessing this spinal condition.
Area of Science:
- Orthopedics
- Biomechanical assessment
- Spinal deformity measurement
Background:
- Radiography is a reliable standard for measuring thoracic kyphosis but is impractical for frequent use due to radiation and cost.
- Clinical methods offer safer, faster alternatives for assessing spinal curvature.
- Limited comparative data exist for digital inclinometers and flexicurves against radiography for thoracic kyphosis measurement.
Purpose of the Study:
- To evaluate the interrater and intrarater reliability and validity of the digital inclinometer and flexicurve for measuring thoracic kyphosis.
- To compare these clinical tools against radiographic measurements (Cobb angle).
Main Methods:
- A cross-sectional study involving 105 patients (aged 10-80) with hyperkyphosis.
- Thoracic kyphosis measured using a digital inclinometer and flexicurve by two blinded examiners.
- Radiographic Cobb angle measured by a spine specialist served as the gold standard.
Main Results:
- The digital inclinometer demonstrated reasonable validity and high intrarater/interrater reliability in patients below 30 and above 50 years.
- The flexicurve showed poor validity across all age groups and poor interrater reliability in younger patients.
- Flexicurve had acceptable intrarater reliability and acceptable interrater reliability in older patients (above 50 years).
Conclusions:
- The digital inclinometer is a valid and reliable instrument for routine thoracic kyphosis screening.
- The flexicurve is not recommended for regular use due to its poor reliability.
- Age-specific validity and reliability should be considered when selecting measurement tools.
