Yvonne Moreno MD, Presenter: Nothing to Disclose

Ronald Steven Adler MD, PhD, Abstract Co-Author: Consultant, Koninklijke Philips Electronics NV

Theodore T. Miller MD, Abstract Co-Author: Nothing to Disclose

Gregory Roy Saboeiro MD, Abstract Co-Author: Nothing to Disclose

To evaluate the effect of tendon sheath injection on the visualization of posterior tibial tendon pathology.

We retrospectively reviewed sonographic images of the posterior tibialis tendon before and after ultrasound guided steroid injection of the tendon sheath. Cases with preexisting tendon sheath effusion were excluded. Five pre-injection and five post-injection images of 10 cases were reviewed separately from each other and independently by three radiologists experienced in musculoskeletal ultrasound. Tendons were scored on four characteristics: tendinosis (heterogeneity), tendon margins (smooth, irregular), tears, and synovial thickening. A severity score from 0 to 4 was assigned in each category using predetermined criteria. Scores were analyzed for inter-observer agreement, both before and after injection, and for changes in individual interpretation by each reader. Scores within 1 unit of each other were considered agreement.

For the pre-injection images, the readers agreed 100% on tendinosis; 73.3% on tendon margins; 90% on tears; and 93.3% on synovial thickening. Post-injection, the readers agreed 96.6% on tendinosis; 66.6% on tendon margins; 96.6% on tears; and 90% on synovial thickening. After fluid injection, one reader had 10 higher and 4 lower scores; one reader had 5 higher and 21 lower scores; the third reader had 9 higher and 8 lower scores. Of these 57 modified scores, 42 were by 1 point. There was a significant difference in tendinosis severity score after fluid injection by one of the readers (t=3.67; df=9; p<0.05). However, there was no significant difference in scoring after fluid injection in the remainder of the categories by any of the readers.  

The presence of injected fluid did not significantly change concordance rates (t=0.577, df=3, p=0.604). While the presence of tendon sheath fluid may result in mild changes in tendon assessment, with exception of one reader’s assessment of tendinosis, we found no clear trend in upgrading or downgrading of tendon scores by any reader after the injection. These findings suggest that the presence of peritendinous fluid following injection does not significantly alter diagnosis of tendon pathology.

Additional scanning following tendon sheath injection does not provide additional diagnostic value.

Moreno, Y, Adler, R, Miller, T, Saboeiro, G, Visualization of Posterior Tibial Tendon Pathology after Ultrasound-guided Tendon Sheath Injection.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034251.html