Variability within and between evaluations of sacroiliac pain with the use of distraction testing.
OBJECTIVE
The objective of this study was to determine whether applied force and time interval of force exposure varied within and between physiotherapists (PTs) when they used sacroiliac (SI) distraction testing to provoke pain among subjects with sacroiliitis.


METHODS
Two force plates recording 3 orthogonal forces and time intervals were used during repetitive testing. Eleven subjects with sacroiliitis were examined with the use of distraction testing by each of 3 PTs. Subjects lay on an examination board equipped with one force plate for each SI joint. They indicated provoked pain by pressing a button that gave a mark in the data collection.


RESULTS
Applied force and time interval of force exposure varied within and between PTs. Significant differences between PTs were found in the impulse (force x time) for the vertical and lateral force components (P <or= .05). A significant decrease was found in the amplitude of force during the time interval of force exposure (P <or= .05) for 2 of the 3 PTs. The median level of pain was lowest when examined by the PT who applied the least magnitude of force.


CONCLUSIONS
Recording force and time events indicates that variation in examination technique within and between PTs may influence the outcome of the distraction test. Such recording, simultaneously monitored by the investigator, would therefore seem to offer standardized testing and improve clinical evaluation of SI pain over time.
Levin
Ulla
U
Division of Physiotherapy, Neurotec Department, Karolinska Institutet, Huddinge, Sweden. Ulla.Levin@ki.se
Nilsson-Wikmar
Lena
L
Stenström
Christina H
CH
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000145:classification / Q000175:diagnosis*; D026741:Physical Therapy Modalities; D015203:Reproducibility of Results; D012446:Sacroiliac Joint / Q000473:pathology*; D011795:Surveys and Questionnaires