Background Even though Doppler ultrasound (US) is used for diagnosing inflammation in arthritides, it is well-known that Doppler signals may be seen in healthy wrist and finger joints (1). Tenosynovitis has been shown to be frequent in rheumatoid arthritis and to predict erosive disease (2). Detailed knowledge of the distribution of feeding vessels in fingers is important to distinguish normal from pathological findings. However, there is no knowledge about Doppler signals in relation to healthy tendon sheaths and the possible pitfalls this may generate.
Objectives To investigate presence of feeding vessels in relation to the healthy flexor and extensor tendon sheaths of the wrist by use of 3D Doppler US.
Methods Twenty healthy participants were recruited; 10 women in the age 27-54 years and 10 men in the age 27-59 years. None of the participants had finger pain, history of arthritis or any known finger tendon disease, or were smokers.
The participants had US of the palmar and dorsal side of the right wrist. US was carried out using a General Electric Logiq E9 with a 3D ultrasound probe. The Doppler settings were adjusted according to published recommendations (3) with a Doppler frequency of 8.3 MHz and PRF of 0.4. The same Doppler settings were used for all examinations. Specific probe positions on the wrist were selected before study initiation at two different levels (Lister's tubercle and pisiforme). Two scans were made at each position to minimise the risk of missing Doppler findings due to different parts of the cardiac cycle being sampled as the sweep was made. Each tendon sheath was divided into specific areas and the visualized 3D Doppler findings in relation to the tendon sheath were plotted on a schematic drawing (Fig. 1A and 1B).
Results The overall distribution of feeding vessels was comparable at the level of Lister's tubercle and the level at the pisiforme for the extensor tendons. For the flexor tendons, feeding vessels were more frequent at the level of Lister's tubercle, as shown in Fig. 1A and 1B. Overall feeding vessels were less frequent for compartment V and VI at the level of Lister's tubercle.
Feeding vessels were seen less at the superficial location for the extensor tendons, except for compartment I.
Radial and dorsal vessels were rare in the tendon sheath of flexor digitorum superficialis and profundus.
Intertendineus feeding vessels were mainly seen in the tendon sheath of flexor digitorum superficialis and profundus.
Conclusions Feeding vessels in close relation to the extensor and flexor tendon sheaths were common in the wrist of healthy participants and may be a cause of misinterpretation due to artefacts. These vessels should be taken into consideration when diagnosing tenosynovitis in the wrist.
Terslev L, Torp-Pedersen S, Qvistgaard E, von der Recke P, Bliddal H. Doppler ultrasound findings in healthy wrists and finger joints. Ann Rheum Dis. 2004
Lillegraven S, Boyesen P, Hammer HB, Ostergaard M, Uhlig T, Sesseng S, et al. Tenosynovitis of the extensor carpi ulnaris tendon predicts erosive progression in early rheumatoid arthritis. Ann Rheum Dis. 2011
Torp-Pedersen ST, Terslev L. Settings and artefacts relevant in colour/power Doppler ultrasound in rheumatology. Ann Rheum Dis. 2008
Disclosure of Interest None declared