Reliability of Evaluating Achilles Tendon Vascularization Assessed With Doppler Ultrasound Advanced Dynamic Flow

Abstract

Objectives The reliability of quantifying intratendinous vascularization by high‐sensitivity Doppler ultrasound advanced dynamic flow has not been examined yet. Therefore, this study aimed to investigate the intraobserver and interobserver reliability of evaluating Achilles tendon vascularization by advanced dynamic flow using established scoring systems. Methods Three investigators evaluated vascularization in 67 recordings in a test‐retest design, applying the Ohberg score, a modified Ohberg score, and a counting score. Intraobserver and interobserver agreement for the Ohberg score and modified Ohberg score was analyzed by the Cohen κ and Fleiss κ coefficients (absolute), Kendall τ b coefficient, and Kendall coefficient of concordance (W; relative). The reliability of the counting score was analyzed by intraclass correlation coefficients (ICC) 2.1 and 3.1, the standard error of measurement (SEM), and Bland‐Altman analysis (bias and limits of agreement [LoA]). Results Intraobserver and interobserver agreement (absolute/relative) ranged from 0.61 to 0.87/0.87 to 0.95 and 0.11 to 0.66/0.76 to 0.89 for the Ohberg score and from 0.81 to 0.87/0.92 to 0.95 and 0.64 to 0.80/0.88 to 0.93 for the modified Ohberg score, respectively. The counting score revealed an intraobserver ICC of 0.94 to 0.97 (SEM, 1.0–1.5; bias, –1; and LoA, 3–4 vessels). The interobserver ICC for the counting score ranged from 0.91 to 0.98 (SEM, 1.0–1.9; bias, 0; and LoA, 3–5 vessels). Conclusions The modified Ohberg score and counting score showed excellent reliability and seem convenient for research and clinical practice. The Ohberg score revealed decent intraobserver but unexpected low interobserver reliability and therefore cannot be recommended.

Ultrasound Doppler Flow in Patients With Chronic Midportion Achilles Tendinopathy: Is Surface Area Quantification a Reliable Method?

“…We found good interobserver reliability for the SAQ method (ICC, 0.81) compared to moderate interobserver reliability for the modified Öhberg score (ICC, 0.64). Similar findings for the ICC of the modified Öhberg score were published by Risch et al, in which moderate absolute interobserver agreement (0.64–0.80) was also observed. Sengkerij et al and Watson et al observed considerably higher ICCs for the modified Öhberg score (0.85 and 0.86, respectively).…”

“…Second, we have not determined intraobserver reliability. In patellar tendinopathy, it was previously demonstrated that day‐to‐day variability in Doppler flow is present; however, in midportion AT, it was shown that the intraobserver reliability of the modified Öhberg score was excellent . Future research should investigate the intraobserver reliability of the SAQ method to verify the diagnostic value of SAQ.…”

“…The interobserver reliability of the modified Öhberg score varies from moderate to perfect . Some studies described other disadvantages of the modified Öhberg score.…”

“…6,[10][11][12][13][14][15][16][17][18] Most of the studies used the modified Öhberg score to quantify the amount of Doppler flow, which has shown higher reliability compared to the original Öhberg score. 19 The modified Öhberg score runs from 0 to 4 + . 4,20 A higher score indicates more Doppler flow in the peritendinous and intratendinous tissues.…”

“…The interobserver reliability of the modified Öhberg score varies from moderate to perfect. 10,12,19 Some studies described other disadvantages of the modified Öhberg score. It is considered to have weak applicability to measure higher amounts of Doppler flow (called the ceiling effect), and the scoring system is operator dependent, since the assessment of the score is difficult.…”