Ultrasound-guided lateral pericapsular hip desensitization of the articular branches of the cranial gluteal nerve: A canine cadaveric study and feasibility study in dogs

Objective: To develop and assess the feasibility, as a diagnostic block, of an ultrasound-guided lateral pericapsular hip desensitization (L-PHD) technique in dogs.

Study design: Prospective, randomized, anatomical and feasibility study.

Animals: A total of 11 canine cadavers and eight adult dogs scheduled for acetabular surgical denervation.

Methods: After studying the ultrasound anatomy of the lateral aspect of the gluteal region and determining an acoustic window to perform an ultrasound-guided L-PHD in three canine cadavers, the right and left hemipelves of eight canine cadavers were injected in the interfascial plane located lateral (L_L-PHD group) or medial (L_M-PHD group) to the deep gluteal muscle, with 0.05 mL kg^-1 of dye per hip on each cadaver. The staining of the pericapsular nerves was assessed by anatomical dissection. Then, the L_M-PHD was performed using 2% lidocaine as a diagnostic block in dogs scheduled for acetabular surgical denervation. Positive predictive value (PPV) was calculated for those animals who had favorable outcomes after acetabular surgical denervation.

Results: The ultrasound-guided L_L-PHD and L_M-PHD could be performed by inserting the needle lateral and medial to the deep gluteal muscle. Ultrasound-guided L_L-PHD stained the cranial gluteal nerve and its muscular branches in all injections and partially stained the lumbosacral trunk in two out of eight cadavers. The L_M-PHD selectively stained the articular branches of the cranial gluteal nerve in all but one cadaver. The PPV for L_M-PHD successful test prediction was 85.7% (95% confidence interval: 48.6% to 98.6%).

Conclusions: and clinical significance Ultrasound-guided L_M-PHD using 0.05 mL kg^-1 of dye selectively stained the articular branches of the cranial gluteal nerve in canine cadavers. The L_M-PHD technique is feasible and could be used as a diagnostic block before acetabular surgical denervation in dogs.