Concurrent validity of digital inclinometer and universal goniometer in assessing passive hip mobility in healthy subjects.

BACKGROUND

Hip range of motion is an important component in assessing clinical orthopedic conditions of the hip, low back and lower extremities. However it remains unclear as to what constitutes the best tool for clinical measurement. The purpose of this study was to investigate the concurrent validity of passive range of motion (ROM) measurements of hip extension and hip internal and external rotation using a digital inclinometer and goniometer.

DESIGN

Criterion Standard.

SETTING

Clinical research laboratory.

PARTICIPANTS

30 healthy subjects without pain, radicular symptoms or history of surgery in the low back or hip regions.

MAIN OUTCOME MEASURES

Passive hip range of motion for extension, hip internal rotation and hip external rotation. A digital inclinometer and universal goniometer were utilized as the tools for comparisons between measurements.

RESULTS

There was a statistically significant difference (p < 0.05) between the goniometer and digital inclinometer in measured hip ROM except for measurements of right hip external rotation (p > 0.05). The mean difference between the goniometer and digital inclinometer in left hip extension, internal rotation and external rotation were 3.5°, 4.5° and 5.0° respectively. The mean difference between the two devices in right hip extension, internal rotation and external rotation were 2.8°, 4.2° and 2.6° respectively. On average, the difference between the goniometer and digital inclinometer in extension was 3.2°, internal rotation was 4.5° and external rotation was 3.8°. The digital inclinometer had greater measurement during EXT and ER. Furthermore, there was no statistically significant difference (p > 0.05) in hip ROM between the left and right side for either goniometric or digital inclinometer measurements.

CONCLUSIONS

This results of this study indicate that a significant difference exists between the two devices in all measurements with exception of right hip extension. The differences were noted to be between 3-5 degrees for all planes measured. These findings suggest that caution should be used if these two devices are to be used interchangeably to quantify passive hip range of motion in either clinical practice or when comparing studies that utilize different instruments.

LEVEL OF EVIDENCE

2b.