A Placebo‐Controlled, Prospective, Randomized Clinical Trial of Polyethylene Glycol and Methylprednisolone Sodium Succinate in Dogs with Intervertebral Disk Herniation

• DOI: 10.1111/jvim.13657
• Publication Date: 2015-11-01T02:45:19Z
• Authors: N.J. Olby; A.C. Muguet‐Chanoit; J.‐H. Lim; M. Davidian; C.L. Mariani; A.C. Freeman; S.R. Platt; J. Humphrey; M. Kent; C. Giovanella; R. Longshore; P.J. Early; K.R. Muñana
• Keywords: Male; Nociception; Anti-Inflammatory Agents; 04 agricultural and veterinary sciences; Polyethylene Glycols; 3. Good health; 0403 veterinary science; 03 medical and health sciences; Dogs; 0302 clinical medicine; Animals; Female; SMALL ANIMAL; Dog Diseases; Methylprednisolone Hemisuccinate; Intervertebral Disc Displacement

BackgroundAcute intervertebral disk herniation (IVDH) is a common cause of spinal cord injury in dogs and currently there is no proven medical treatment to counter secondary injury effects. Use of methylprednisolone sodium succinate (MPSS) or polyethylene glycol (PEG) as neuroprotectants is advocated but controversial because neither treatment has been tested in placebo‐controlled, randomized, blinded trials in dogs.HypothesisPolyethylene glycol will improve the outcome of severe spinal cord injury caused byIVDHcompared toMPSSor placebo.AnimalsClient‐owned dogs with acute onset of thoracolumbarIVDHcausing paralysis and loss of nociception for <24 hours.MethodsDogs were randomized to receiveMPSS,PEG, or placebo; drugs appeared identical and group allocation was masked. Drug administration was initiated once the diagnosis ofIVDHwas confirmed and all dogs underwent hemilaminectomy. Neurologic function was assessed 2, 4, 8, and 12 weeks postoperatively using an open field gait score (OFS) as the primary outcome measure. Outcomes were compared by the Wilcoxon rank sum test.ResultsSixty‐three dogs were recruited and 47.6% recovered ambulation. 17.5% developed progressive myelomalacia but there was no association with group. There was no difference inOFSamong groups. Although full study power was not reached, conditional power analyses indicated the futility of continued case recruitment.ConclusionsThis clinical trial did not show a benefit of eitherMPSSorPEGin the treatment of acute, severe thoracolumbarIVDHwhen used as adjunctive medical treatment administered to dogs presenting within 24 hours of onset of paralysis.