The document discusses the placebo effect and how it relates to surgery and pain management. It references several studies on placebo effects mediated by the brain's opioid and dopamine systems. Placebo effects are influenced by expectations, environmental context, and the patient-practitioner interaction. Studies show placebo analgesia can be enhanced through memory, semantic processing, and classical conditioning. However, placebo effects may be reduced in conditions like Alzheimer's where expectation mechanisms are impaired. The size of the placebo effect varies for different conditions, like a 0.77 effect size for osteoarthritis. Attitudes, branding, colors, and costs can also influence placebo responses.

1. effet placebo
Dr. med. Camillo Theo Müller
Centre de la Main
Service de chirurgie plastique et de la main
CHUV

2. effet placebo
• Quoi?
• Comment?
• En chirurgie ?

3. Understanding placebo effects in rheumatology // Abhishek A, Doherty M.
Joint Bone Spine. 2015 Jul;82(4):222-4. doi: 10.1016/j.jbspin.2015.01.013. No abstract available. PMID: 2577645

4. Placebo effects mediated by endogenous opioid activity on mu-opioid receptors.
Zubieta JK, Bueller JA, Jackson LR, Scott DJ, Xu Y, Koeppe RA, Nichols TE, Stohler CS.
J Neurosci. 2005 Aug 24;25(34):7754-62. PMID: 16120776

5. Neuropharmacological dissection of placebo analgesia: expectation-activated opioid systems versus conditioning-activated specific
subsystems. Amanzio M, Benedetti F. J Neurosci. 1999 Jan 1;19(1):484-94. PMID: 9870976

6. Placebo - Nocebo ?
- Brain damage?
D.J. Scott, C.S. Stohler, C.M. Egnatuk, et al.Placebo and nocebo effects are defined by opposite opioid and dopaminergic
responses Arch Gen Psychiatry, 65 (2008), pp. 220–231

7. F. Benedetti, C. Arduino, S. Costa, et al. Loss of expectation-related mechanisms in Alzheimer's disease makes analgesic therapies
less effective Pain, 121 (2006), pp. 133–144

8. J.G. Craggs, D.D. Price, M.E. Robinson // Enhancing the placebo response: functional magnetic resonance imaging evidence of
memory and semantic processing in placebo analgesia J Pain, 15 (2014), pp. 435–446

9. Osteoarthritis
• effet placebo 0,77 (0,65-0,89)
• AINS 0,2-0,3
• Sans TT - 0,08
Osteoarthritis – National clinical guideline for care and management in adults. NICE and Royal College of Physicians guidelines on
osteoarthritis NICE, London (2008)

10. Immunosuppression ?
D.W. Giang, A.D. Goodman, R.B. Schiffer, et al. // Conditioning of cyclophosphamide-induced leukopenia in humans
J Neuropsychiatry Clin Neurosci, 8 (1996), pp. 194–201

11. La réponse contextuelle
- Esperance
- Environment
- Interaction practicien – patient
Consultation: chalereuse, attentionée, confidante et optimiste

12. A. Abhishek, M. Doherty // Mechanisms of the placebo response in pain in osteoarthritis
Osteoarthritis Cartilage, 21 (2013), pp. 1229–1235

13. Coulour // Noumber
Branding // Cost
Branthwaite A, Cooper P. Analgesic effects of branding in
treatment of headaches. Br Med J (Clin Res Ed) 1981;282:
1576e8.
Moerman DE, Jonas WB. Deconstructing the placebo effect and
finding the meaning response. Ann Intern Med 2002;136:471e6.

14. Attitudes of Hand Surgeons, Hand Surgery Patients
Attitudes of Hand Surgeons, Hand Surgery Patients, and the General Public Regarding Psychologic Influences on Illness
by Paige Mallette, David Ring ISSN: 03635023 DOI: 10.1016/j.jhsa.2006.06.002 PubMed: 17027800