Reliability Index of inter- and intra-rater of manual goniometry and computerized biophotogrammetry to assess the range of motion of internal and external shoulder rotation

Abstract

Measurements of the joint angles of the shoulder complex are important for diagnosis, assessment and monitoring of the treatment progression of movement disorders, provided that they can be seen as valid and reliable. The object of this study was to determine inter-and intra-rater reliability of manual goniometry and computerized biophotogrammetry for the assessment of range of motion of the medial and lateral rotations of the shoulder. METHODS: Four evaluators (two for goniometry and two for biophotogrammetry) assessed 11 males, 16-26 years old, right-handed and with no shoulder anomalies. A universal plastic goniometer was used for the goniometry assessment. The biophotogrammetry assessment involved the use of a digital camera Sony DSC-W1 (5.1Mp), with non-reflective markers placed on the subjects. Photographic frames were analyzed the though the SAPO software (version 0.67). Each evaluator was blinded to data from all other valuators; inter-rater datas were compared. Seven days after the first assessment, all measurements were repeated in order to complete the intra-rater comparison. The Wilcoxon test was used to check statistical significance, the Spearman correlation was calculated and inter-class correlations coefficients were determined. RESULTS: Inter-class correlations for inter-and intra-rater goniometry results were 0.897 and 0.830 respectively; the corresponding biophotogrammetric values were 0.982 and 0.954, all representing excellent reliability levels. CONCLUSION: Goniometry and biophotogrammetry are reliable methods for assessment of shoulder rotation; however, biophotogrammetry has been shown to be more reliable.