Reproducibility and clinical utility of manual muscle testing (MMT) for children with Spina Bifida

Abstract

Objective: Manual muscle testing (MMT) is used to monitor muscle strength/weakness and associated neurological status of children with spina bifida.(1) For this to be clinically valid, a standardized and reliable protocol for children with spina bifida is critical. The Daniels and Worthingham (D&W) MMT protocol(2) has been recommended by the International Myelodysplasia Study Group(3) due to its detailed methodological information. However, the D&W Protocol was developed for adults, and its reliability has not been established for children. This study aims to examine the inter-rater reliability of the D&W MMT protocol for children with spina bifida. Design: Cross-sectional study. Method: Thirteen children with Spina Bifida (2 males) aged 6 to 18 years (mean 12y 6mo, SD 2y 9mo) were recruited from a Spina Bifida service in a state-wide tertiary children's hospital. Each child had strength of 19 lower limb muscles examined bilaterally using the D&W MMT protocol by one experienced and one novice physiotherapist. Examiner and limb order was counterbalanced. Fidelity was enhanced by (1) recreation of the D&W photo guide for each MMT test for each muscle with a child model; (2) development of a standardized recording form, (3) examiner training with children not in the study until agreement was reached on technique and scoring. Analysis of agreement between examiners was performed using quadratic weighted kappa (jw2), percent exact agreement (%EA) and Bland-Altmann limits of agreement (LoA). Minimal detectable change (MDC) was calculated to determine minimum change required to detect real clinical deterioration. Results: The D&W MMT protocol shows excellent inter-rater agreement (jw2=0.950; 95% CI: 0.935-0.962); good exact agreement (72.29%); and clinically appropriate limits of agreement (-1.302 to 1.402) when results of experienced versus novice raters are compared. The MDC was 1.11 points, indicating a change of 2-points is required to detect clinical change on the 6-point scale. Conclusion: The D&W MMT protocol, when used after standard training and with standard prompt sheet and recording sheet, is reliable for use with children with Spina Bifida.L6148362972017-03-21 <br />