Fig. 5. Step 3: Inject a 1- to 2-mL bleb of local anesthetic cranial and adjacent to the probe.
Fig. 3. Step 2: Rotate the ultrasound probe 90° into a trans- verse position, staying centered over the MFT joint recess.
“bleb” was used as a landmark (Fig. 6) for replace- ment of the probe once the local anesthetic had taken effect and decreased any further discomfort that could arise from introduction of the needle used for injection. The syringe with the 22-gauge needle attached was slowly introduced through the skin (Fig. 7) at the cranial margin of the ultrasound probe. The needle was pushed through the femoral
fascia into the recess, and the plunger was de- pressed (Fig. 8). The contents of the syringe were observed to enter the recess (Fig. 9). The syringe and needle were then withdrawn. When the procedure was used to administer med- ications or for a contrast study of the MFT joint, the horse was sedated intravenously with detomidine HCLb (0.01 mg/kg) and butorphanol tartrated (0.01 mg/kg). Because food is not an incentive to a sedated horse, the level of sedation was tested before injection by carefully palpating the outer sheath or
Fig. 4. Transverse reference sonogram of the MFT joint recess through the use of the craniomedial approach pictured in Fig. 3. Cranial is to the left and caudal to the right. 1, Femoral fascia; 2, MFT joint recess; 3, femoral condyle.
222 2013 Vol. 59 AAEP PROCEEDINGS
Fig. 6. Step 4: Replace the probe transversely with the skin bleb used as a landmark.
