Acute canine spinal cord injury from disc extrusion: does methylprednisolone sodium succinate improve neurological recovery? — POSSIBLE (the treatment made no difference)

POSSIBLE (the treatment made no difference): On neurological recovery — the shelf's primary outcome — methylprednisolone sodium succinate (MPSS) made no difference in the only randomised blinded trial or in the one controlled comparison, and the stamp's null suffix is scoped to that recovery outcome. Olby 2016 (PMID: 26520829), a placebo-controlled, prospective, randomized clinical trial in 63 client-owned dogs with acute thoracolumbar intervertebral disk herniation causing paralysis and loss of nociception for <24 hours, all treated with hemilaminectomy, randomised dogs to MPSS (30 mg/kg bolus then 5.4 mg/kg/h infusion; n = 21), polyethylene glycol (n = 24) or saline placebo (n = 18), with identical-appearing drugs and masked allocation: there was no difference in the primary outcome, open field gait score (OFS), among groups at any evaluation, and at 12 weeks the median OFS was 7.5 (range 1–11.5) on saline vs 5 (range 0–11.5) on MPSS while independent walking was regained by 7 of 18 (38.9%) saline dogs vs 11 of 21 (52.4%) MPSS dogs — a non-significant numerical difference in the dichotomous outcome against a lower median gait score, with all 12-week comparisons non-significant; overall 30 of 63 dogs (47.6%) recovered ambulation and 11 of 63 (17.5%) developed progressive myelomalacia with no association with group, and recruitment was stopped early after conditional power analyses (all conditional powers <0.56) indicated futility. Nishida 2016 (PMID: 29786990), a controlled clinical trial in 50 dogs with surgically treated Hansen type I thoracolumbar herniation, likewise found no significant difference in recovery rate or length of recovery time between MPSS and non-administration groups — but its record reports no absolute recovery rates, so it is carded for its authors' conclusion only and no recovery rate may be quoted from it; its one positive finding, significantly reduced spinal cord swelling (with myelography localisation sensitivity 92.3% on MPSS vs 83.3% without), is an imaging surrogate, not neurological recovery, and is disclosed here as a counter-signal that does not disturb the recovery null. Design class (a): Olby 2016 establishes randomisation and blinding for this shelf's own comparison and population — dogs were randomized, drugs appeared identical, group allocation was masked, and nociception and proprioceptive placing recorded on study forms were confirmed by 2 independent, blinded observers reviewing videotapes. Narrowings stated on the face: (1) Both carded records study surgically treated thoracolumbar Hansen type I disc extrusion/herniation, and Olby 2016 enrolled only the most severe grade — paralysis with loss of nociception, presented within 24 hours, dogs <20 kg aged 2–10 years — so the null is established for severe surgically treated thoracolumbar extrusion and is not direct evidence for cervical extrusion, milder grades, or medically managed dogs. (2) The mined question says 'vs no steroid'; Olby's comparator was saline placebo with no steroid, and Nishida's was non-administration, so both answer MPSS vs no steroid in substance. Near-misses, not carded: Castel 2019 (PMID: 31796017), a retrospective case-control study of progressive myelomalacia after disc extrusion in 197 dogs, examined corticosteroids as a pooled exposure (not MPSS specifically) for a myelomalacia outcome, not neurological recovery — its corticosteroid association is not carded here; Natsios 2025 (PMID: 39727220), a prospective randomised blinded trial of LOCAL EPIDURAL methylprednisolone ACETATE (a different formulation and route, applied at surgery; median time to ambulation 3 vs 7 days on saline) — not systemic MPSS and not carded on this shelf; Levine 2008 (PMID: 18241109) studied dexamethasone, a different steroid. Tier C adjudication, recorded on the face: Tier C is NOT engaged — no carded record makes a mortality or survival-primary benefit claim; progressive myelomalacia with euthanasia in Olby 2016 (17.5% overall) showed no association with treatment group and is a harm/complication outcome, not a survival benefit claim. Drafted Nov 10, 2026 (VetMed build, topic #450); figures from the abstracts and the Olby 2016 PMC full text fetched and verified at drafting (the full text governs where it differs from the abstract).