Oertzenweg 19 b
Tel.+49 30 838 62299 Fax.+49 30 838 62529
Navicular bursa injections are routinely used in horses with foot pain for diagnostic and therapeutic purposes. Ultrasound-guided injections to the navicular bursa have been proposed as an alternative to traditional techniques. The objective of this study was to develop an ultrasound-guided injection technique to access the navicular bursa using the palmarodistal digital approach and evaluate the success rate, total execution time, number of needle positioning, and ultrasonographic verification of bursal injection compared with contrast radiology. We hypothesized that this technique would be fast and accurate; necessitating few needle repositions and allowing real-time ultrasonographic guidance and verification of bursal injection. Overall success rate was 92.5% (37 of 40). Optimal images presented a success rate of 100% (32 of 32) and suboptimal images of 62.5% (5 of 8). Intrabursal accumulation of radiographic contrast media was correlated in 97.3% (36 of 37) of the limbs to ultrasonographic evidence of fluid and gas in the navicular bursa. Mean total execution time was 16.1 second (±7.84 seconds). Mean number of needle insertions per limb was 1.23 (±0.42). All the needle repositions (9 of 40) were performed within the digital cushion. Our results using cadaver limbs suggest that this approach allows a high injection success rate, high execution speed, accurate confirmation of intrabursal injection, and a low needle reposition rates. Needle repositioning within the digital cushion could minimize the number of unnecessary needle penetrations to the deep digital flexor tendon. Acquisition of suboptimal ultrasound images may preclude the use of this technique because it importantly impacts the injection success rate.