Initial validation of the LSPain Scale: a behaviour-based clinical tool for canine lumbosacral pain

Roger Medina Serra^1*Sandra Sanchis Mora²Clara Conde Ruiz³Francesco Aprea⁴Eliseo Belda Mellado^5,6Francisco G Laredo^5,6Miguel Angel Cabezas⁷

• ¹Anaesthesia and Pain Management, North Downs Specialist Referrals, part of Linnaeus Veterinary Limited, Bletchingley, United Kingdom
• ²Blaise Veterinary Referral Hospital, Birmingham, United Kingdom
• ³Service d'anesthésie et algologie. CHV AniCura Armonia, 500 Rue du Chatelier- Lieu dit "les Sables", Vaulx-Milieu, France
• ⁴Hospital Veterinari Canis Mallorca, Mallorca, Spain
• ⁵Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad de Murcia, Murcia, Spain
• ⁶Hospital Veterinario Universidad de Murcia, Murcia, Spain
• ⁷Departamento de Medicina y Cirugía Animal, Universidad Complutense de Madrid, Madrid, Spain

This study aimed to validate the LSPain Scale, a novel 4-point ordinal instrument for assessing lumbosacral pain in dogs based on behavioural responses to palpation of the lumbosacral region. A preliminary analysis was conducted using clinical data to inform sample size estimation and to explore the scale's convergent validity and responsiveness. Subsequently, a prospective validation was performed using 50 anonymised clinical videos retrospectively collected from client-owned dogs evaluated for suspected lumbosacral pain. Dogs represented a broad clinical spectrum and were graded using the LSPain Scale, where scores range from 0 (no pain) to 3 (severe pain). Trained observers, including pain specialists and general practitioners, independently scored the videos while blinded to clinical data. Psychometric evaluation demonstrated strong convergent and discriminant validity, responsiveness to treatment, inter-and intra-rater reliability, and usability across experience levels. The findings support the LSPain Scale as a valid and reliable clinician-based tool for standardised assessment and monitoring of lumbosacral pain in dogs.