The reliability of the three-dimensional FASTRAK measurement system in measuring cervical spine and shoulder range of motion in healthy subjects.
OBJECTIVE
To assess the inter-observer and intra-observer reliability of a new three-dimensional measurement system, the FASTRAK, in measuring cervical spine flexion/extension, lateral flexion and rotation and shoulder flexion/extension, abduction and external rotation in healthy subjects.


METHODS
The study was conducted in two parts. One part assessed inter-observer reliability with two observers measuring 40 subjects. The other part assessed intra-observer reliability with one observer measuring 32 subjects on three occasions. All subjects had unrestricted, pain-free cervical spine and shoulder movement. Reliability was measured by the intraclass correlation coefficient [ICC(2,1)].


RESULTS
The inter-observer ICCs for the cervical spine ranged from 0.61 to 0.89 and for the shoulder from 0.68 to 0.75. After removal of outliers, all ICCs were above 0.70. Intra-observer ICCs for the cervical spine ranged from 0.54 to 0.82 and for the shoulder from 0.62 to 0.81. After removal of outliers, all ICCs were above 0.70 except for shoulder abduction (0.62).


CONCLUSIONS
Whilst all movements measured by the FASTRAK showed good reliability, the reliability of the whole movement in a plane (e.g. left plus right lateral flexion) was better than for the separate movements (e.g. left and right lateral flexion taken separately). Inter-observer reliability was generally better than intra-observer reliability for most cervical spine movements, suggesting that variability of movement within subjects (e.g. over a period of days) for these movements was greater than variability between measures on the same occasion.
Jordan
K
K
Centre for Health Planning & Management, Darwin Building, Keele University, Keele, UK.
Dziedzic
K
K
Jones
P W
PW
Ong
B N
BN
Dawes
P T
PT
D000328:Adult; D000886:Anthropometry; D001696:Biomechanical Phenomena; D002574:Cervical Vertebrae / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D012785:Shoulder Joint / Q000502:physiology*