title: Defining local nerve blocks for feline distal pelvic limb surgery: a cadaveric study.
abstract: Objectives Anatomical and methodological detail is lacking regarding local anesthetic peripheral nerve block techniques for distal pelvic limb surgery in cats. The aim of this study was to develop, describe and test nerve block methods based on cadaveric dissections and dye injections. Methods Ten pairs of feline pelvic limbs (n = 20) were dissected and the tibial nerve (T n.), common fibular (peroneal) nerve (CF n., and its two branches, the superficial fibular [peroneal] nerve [SpF n.] and the deep fibular [peroneal] nerve [DpF n.]) and the saphenous nerve (Sa n.) were identified. Based on these dissections, a 'distal crus block' (selective blockade of the CF n., T n. and Sa n.) and a 'distal pes block' (selective blockade of the SpF n., DpF n., T n. and Sa n.) were developed for surgical procedures in two different regions of the distal pelvic limb. Techniques were tested using new methylene blue (NMB) dye injections in feline pelvic limbs (n = 12). Using a 25 G × 5/8 inch needle and 1 ml syringe, 0.1 ml/kg of NMB dye solution was injected at the site of the CF n., and 0.05 ml/kg was injected at the sites of the SpF n., DpF n., Sa n. and T n. The length and circumference (fully or partially stained) of each stained nerve were measured. Results Positive staining of nerves was observed in 12/12 limbs. The lengths stained for the CF n., DpF n., SpF n., Sa n. and T n. were 27.19 ± 7.13, 20.39 ± 5.57, 22.82 ± 7.13, 30.89 ± 6.99 and 25.16 ± 8.09 mm, respectively. The nerves were fully stained in 12, 12, 10, 11 and 11 out of 12 limbs, respectively. Conclusions and relevance These two, three-point injection methods may be an effective perioperative analgesia technique for feline distal pelvic limb procedures.
authors.affiliation: 1 Comparative Pain Research Laboratory, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA.
authors.forename: Masataka
authors.initials: M
authors.lastname: Enomoto
authors.affiliation: 1 Comparative Pain Research Laboratory, Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA.|2 Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA.|3 Center for Pain Research and Innovation, University of North Carolina, School of Dentistry, Chapel Hill, NC, USA.|4 Center for Translational Pain Research, Department of Anesthesiology, Duke University, Durham, NC, USA.
authors.forename: B Duncan X
authors.initials: BDX
authors.lastname: Lascelles
authors.affiliation: 5 Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA.
authors.forename: Mathew P
authors.initials: MP
authors.lastname: Gerard
mesh_terms: D000779:Anesthetics, Local / Q000008:administration & dosage*; D000818:Animals; D002102:Cadaver; D002415:Cats / Q000033:anatomy & histology*; D005260:Female; D006614:Hindlimb / Q000294:innervation* / Q000601:surgery; D008297:Male; D008751:Methylene Blue / Q000031:analogs & derivatives; D009407:Nerve Block / Q000379:methods / Q000662:veterinary*; D010543:Peroneal Nerve / Q000033:anatomy & histology*
chemical_list: D000779:Anesthetics, Local; C035184:new methylene blue; D008751:Methylene Blue