Table 1 Overview of validity and inter-rater reliability for knee goniometry

Lavernia et al [23]

Mean difference between radiologic and goniometric measurement up to 13 degrees with wide (up to 20 degrees) 95% limits of agreement

1-way ANOVA method determined a significant difference between raters for visual and measured range of motion

Standard goniometer; supine.

Lenssen et al [24]

Mean difference (95% limits of agreement) between raters differed by position tested and angle:

1.4 degrees (-16.2 to 19 degrees) (flexion/supine);

2.7 (-6.7 to 12.1) (flexion, sitting);

2.2 (-6.2 to 10.6) (extension, sitting)

Long-arm goniometer; sitting and supine.

Edwards et al [16]

22% of the goniometric measurements were different by 5 degrees or more

Correlation coefficient, 0.91 (type not specified).

Standard goniometer; supine.

Brosseau et al [14]

r = 0.975-0.987 (flexion),

r = 0.390-0.514 (extension).

ICC, 0.959-0.982 (flexion);

ICC 0.856-0.926 (extension). Both devices performed similarly.

Parallelogram and Universal goniometer; supine.

Brosseau et al [15]

r = 0.73-0.78 (flexion),

r = 0.33-0.48 (extension).

ICC, 0.82-0.88 (flexion); ICC 0.43-0.52 (extension). Both devices performed similarly, but the parallelogram provided more advantages to the clinician.

Parallelogram and Universal goniometer; supine.

Watkins et al [19]

ICC 0.90 (flexion); ICC, 0.86 (extension)

Standard goniometer; positioned varied.

Gogia et al [22]

ICC 0.98-0.99.

ICC 0.99

Standard goniometry; side-lying.

Rothstein et al [18]

ICC 0.84-0.93 (flexion); ICC 0.59-0.80 (extension). All devices performed similarly.

3 different standard goniometers; position not specified.

Lawrence, cited by Johnson [17]

r = 0.94 (extension and flexion angles combined).

Intra-observer error +/- 2.3 degrees for end flexion (aggregate standard deviation).

Inter-observer error +/- 2.6 degrees end extension and +/-4.2 degrees end flexion

Extended goniometer; supine position.

Cleffken et al [20]

Passive end of range flexion - Smallest detectable difference 0 ± 6.4 degrees

Electronic digital inclinometer; supine