Quantitative Paraspinal Muscle Measurements: Inter-Software Reliability and Agreement Using OsiriX and ImageJ

Maryse Fortin; Michele C. Battié

doi:10.2522/ptj.20110380

Figures

Figure 1.

(A) Measurement of total cross-sectional area of erector spinae and multifidus muscles (right) at L4–L5. Lean muscle functional cross-sectional area (FCSA) of the paraspinal muscle group using a threshold method is represented by the area highlighted in green (left). (B) Sample selection of regions of interest to define upper and lower signal intensity threshold limits.

Figure 2.

Bland-Altman 95% limits of agreement plots for the different muscle composition measurements of the left multifidus muscle at L4–L5. CSA=cross-sectional area, FCSA=functional CSA, CSA diff=side-to-side difference in CSA, FCSA diff=side-to-side difference in functional CSA, FCSA/CSA=ratio.

Appendix.

Specific Protocols for Obtaining Muscle Cross-Sectional Area (CSA) and Functional CSA (FCSA) Signal Measurement

Tables

Table 1.

Inter-Software Reliability Indexes for Left Paraspinal Muscle Measurements at L4–L5^{^a}

↵^a ICC=intraclass correlation coefficient, CI=confidence interval, SEM=standard error of measurement, CSA=cross-sectional area, SI=signal intensity, FCSA=functional CSA, FCSA/CSA=ratio, CSA diff=side-to-side difference in CSA, FCSA diff=side-to-side difference in functional CSA.

Table 2.

Inter-Software Reliability Indexes for Left Paraspinal Muscle Measurements at S1^{^a}

↵^a ICC=intraclass correlation coefficient, CI=confidence interval, SEM=standard error of measurement, CSA=cross-sectional area, SI=signal intensity, FCSA=functional CSA, FCSA/CSA=ratio, CSA diff=side-to-side difference in CSA, FCSA diff=side-to-side difference in functional CSA.

Table 3.

Intrarater Reliability Indexes for OsiriX and ImageJ for Left Paraspinal Muscle Measurements at L4–L5^{^a}

↵^a ICC=intraclass correlation coefficient, CI=confidence interval, SEM=standard error of measurement, CSA=cross-sectional area, SI=signal intensity, FCSA=functional CSA, FCSA/CSA=ratio, CSA diff=side-to-side difference in CSA, FCSA diff=side-to-side difference in functional CSA.

Table 4.

Intrarater Reliability Indexes for OsiriX and ImageJ for Left Paraspinal Muscle Measurements at S1^{^a}

↵^a ICC=intraclass correlation coefficient, CI=confidence interval, SEM=standard error of measurement, CSA=cross-sectional area, SI=signal intensity, FCSA=functional CSA, FCSA/CSA=ratio, CSA diff=side-to-side difference in CSA, FCSA diff=side-to-side difference in functional CSA.