Abstract
Purpose:
The purpose of this study was to investigate the consistency between different Doppler
ultrasound (DU) modes as well as the intra- and inter-observer reliability of investigators
with different experience level in assessing intratendinous blood flow (IBF) in Achilles
tendinopathy patients.
Material and Methods:
18 participants (36 Achilles tendons, AT) with Achilles tendinopathy (24 AT) were
examined with power Doppler ultrasound (PDU), colour Doppler ultrasound (CDU) and
“Advanced Dynamic Flow” (ADF) (Toshiba Xario SSA-660 A; 14MHz transducer) by 2 investigators
(experienced, EI; inexperienced, II) in a test-retest design (M1/M2). A modified Öhberg
score was used to quantify IBF. Data was analysed descriptively (absolute and relative).
Consistency of the 3 modes was presented by Kendall’s Coefficient of Concordance (Kendall’s
W). Intra- and inter-observer reliability were calculated by use of Kendall’s tau
b correlation coefficient.
Results:
IBF was detected in 79–92% of symptomatic AT and in 33–50% of contralateral asymptomatic
AT. Comparing the 3 modes, Kendall’s W ranged from 0.97–0.98. Analysis of intra-observer
reliability resulted in Kendall’s tau 0.90–0.92 for EI and 0.84–0.87 for II. Inter-observer
reliability resulted in Kendall’s tau 0.64–0.69 in M1 and 0.68–0.70 in M2.
Conclusion:
The very good consistency between PDU, CDU and ADF indicates a comparable applicability
for assessing IBF in ATs. Intra-observer reliability was high for both investigators,
independent of experience. The moderate inter-observer reliability reflects the challenge
in sonographic detection of intratendinous blood flow (IBF) amount.
Key words
ultrasound-power doppler - ultrasound-color doppler - advanced dynamic flow - achilles
tendon - reliability
