Electrophysiological characterisation of central sensitisation in canine spontaneous osteoarthritis

Murrell, Joanna C.; Whay, Helen R.; Mendl, Michael; Lascelles, B. Duncan X.; Hunt, James R.; Hunt, James Russell; Goff, Megan; Jenkins, Helen; Harris, John; Knowles, Toby G.; Lascelles, Duncan; Enomoto, Masataka; Mendl, Mike; Whay, Becky; Murrell, Jo C.

Abstract

In man, central sensitisation (CS) contributes to the pain of osteoarthritis (OA). Dogs with spontaneous OA may also exhibit CS. Electrophysiological reflex measurements are more objective than behavioural assessments, and can be used to evaluate CS in preclinical and clinical studies. It was hypothesised that dogs suffering from OA would exhibit electrophysiological characteristics indicative of CS, associated with reduced diffuse noxious inhibitory controls (DNIC). 117 client owned dogs were recruited to the study. Hindlimb nociceptive withdrawal reflex (NWR) thresholds, stimulus response, and temporal summation characteristics were recorded, during alfaxalone anaesthesia, from 46 OA dogs, 29 OA dogs receiving non-steroidal anti-inflammatory drugs (OANSAID), and 27 breed- and weight-matched control dogs. Efficacy of DNIC was evaluated in 12 control and 11 of the OA dogs, by application of a mechanical conditioning stimulus to the contralateral forelimb. NWR thresholds were higher in OA compared with control dogs (p = 0.02). Stimulus response characteristics demonstrated an augmented response in OANSAID dogs compared with OA (p < 0.001) and control (p < 0.001) dogs. Temporal summation demonstrated exaggerated C-fibre mediated responses in both OA (p < 0.001) and OANSAID (p = 0.005) groups, compared with control animals. Conditioning stimulus application resulted in inhibition of test reflex responses in both OA and control animals (p < 0.001); control animals demonstrated greater inhibition compared with OA (p = 0.0499). These data provide evidence of neurophysiological changes consistent with CS in dogs with spontaneous OA, and demonstrate that canine OA is associated with reduced DNIC.

Citation

Murrell, J. C., Whay, H. R., Mendl, M., Lascelles, B. D. X., Hunt, J. R., Hunt, J. R., …Murrell, J. C. (2018). Electrophysiological characterisation of central sensitisation in canine spontaneous osteoarthritis. PAIN, 159(11), 2318-2330. https://doi.org/10.1097/j.pain.0000000000001336

• Journal Article Type: Article
• Acceptance Date: Jul 2, 2018
• Online Publication Date: Jul 9, 2018
• Publication Date: 2018-11
• Deposit Date: Jul 10, 2018
• Publicly Available Date: Jul 10, 2019
• Journal: Pain
• Print ISSN: 0304-3959
• Electronic ISSN: 1872-6623
• Publisher: Lippincott, Williams & Wilkins
• Peer Reviewed: Peer Reviewed
• Volume: 159
• Issue: 11
• Pages: 2318-2330
• DOI: https://doi.org/10.1097/j.pain.0000000000001336
• Keywords: Central sensitisation; Diffuse Noxious Inhibitory Controls; Dog; Nociceptive Withdrawal Reflex; Osteoarthritis
• Public URL: https://nottingham-repository.worktribe.com/output/945710
• Publisher URL: https://journals.lww.com/pain/Abstract/publishahead/Electrophysiological_Characterisation_of_Central.98906.aspx