Evidence map›Paper›PMID 40924628›Full record

ArticleAnesthesia and analgesia2026

Acute Pain After Total Knee Arthroplasty: 2-Arachidonoylglycerol Tone and Endocannabinoid/Eicosanoid Crosstalk.

Livia Schutz, Chris Gordon, Mariam Hassan, Keith Studholme, Ayesha Khan, Alexa Christophides, Darcy Halper, Samuel Stanley, James Nicholson, Elliott Bennett-Guerrero and 2 more

Abstract read
In one paragraph

Article in Anesthesia and analgesia, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

12 authors.

Livia SchutzFrom the Department of Anesthesiology.
Chris GordonFrom the Department of Anesthesiology.
Mariam HassanFrom the Department of Anesthesiology.
Keith StudholmeFrom the Department of Anesthesiology.
Ayesha KhanFrom the Department of Anesthesiology.
Alexa ChristophidesFrom the Department of Anesthesiology.
Darcy HalperFrom the Department of Anesthesiology.
Samuel StanleyFrom the Department of Anesthesiology.
James NicholsonDepartment of Orthopaedics and Rehabilitation.
Elliott Bennett-GuerreroFrom the Department of Anesthesiology.
David E KomatsuDepartment of Orthopaedics and Rehabilitation.
Martin KaczochaFrom the Department of Anesthesiology.

Funding

Endocannabinoid Metabolism in Acute PainR01DA048002 · NIDA · STATE UNIVERSITY NEW YORK STONY BROOK · PI KACZOCHA, MARTIN · 2020 to 2024
$2.3M
National Institute on Drug Abuse (US) DA048002NIDA NIH HHS R01 DA048002
6 · The paper itself

Abstract

backgroundTotal knee arthroplasty (TKA) is a surgical procedure that induces intense acute postoperative pain, but the mechanisms that amplify post-TKA pain remain incompletely understood. Endocannabinoids, such as 2-arachidonoylglycerol (2-AG), are endogenous lipids that can produce antinociceptive effects. However, hydrolysis of 2-AG by monoacylglycerol lipase (MAGL) generates arachidonic acid, the precursor to a host of eicosanoids that enhance pain. The presence of this metabolic pathway suggests that individuals with elevated 2-AG levels may be primed to develop greater postoperative pain.

methodsThe primary goal of this prospective study was to determine if intraoperative 2-AG levels in the synovial fluid (SF) and cerebrospinal fluid (CSF) of TKA patients are associated with the magnitude of acute postoperative pain at rest and with ambulation. The secondary goal was to determine whether 2-AG metabolism contributes to prostaglandin E 2 (PGE 2 ) biosynthesis in synovial tissue ex vivo.

resultsNinety subjects were enrolled in the study. SF 2-AG was positively correlated with pain at rest (r = 0.2644; P = .0157) and with ambulation (r = 0.3856; P = .0005) while CSF 2-AG was associated with pain at rest (r = 0.3312; P = .0017) but not with ambulation (r = 0.1454; P = .1871). Stratification of the results by sex revealed positive correlations between 2-AG and pain in females, which were markedly weaker or not observed in males. Ex vivo analysis demonstrated coexpression of MAGL and cyclooxygenase-2 in synovial membranes, with MAGL inhibition by MJN110 elevating 2-AG levels (median, vehicle: 0.165 nmol/g vs MJN110: 0.325 nmol/g, P = .0269) and concomitantly reducing PGE 2 (median, vehicle: 5.645 nmol/g vs MJN110: 3.440 nmol/g, P = .0425).

conclusionsOur findings demonstrate that patients presenting with an elevated 2-AG tone develop greater postoperative pain and position MAGL as an enzymatic node linking 2-AG metabolism with eicosanoid biosynthesis in perioperative human tissue.

Indexed as

Acute PainArachidonic AcidsArthroplasty, Replacement, KneeEicosanoidsEndocannabinoidsGlyceridesPostoperative PainAgedAged, 80 and overDinoprostoneFemaleHumansMaleMiddle AgedProspective StudiesSynovial FluidArachidonic AcidsDinoprostoneEicosanoidsEndocannabinoidsGlyceridesglyceryl 2-arachidonate

Identifiers

PMID40924628
PMCPMC12720205

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.