# Preoperative risk factors: association and limits

> **Educational work by a pre-medical student — not medical advice.** Not a clinical protocol, prescription, or patient handout, and not for patient care. See [DISCLAIMER](DISCLAIMER.md).

Independent educational note, revised 27 October 2026. The earlier unverified prevalence estimates, fixed dose thresholds, screening performance and causal claims are withdrawn.

[Goesling et al., 2016, PMID 26871536](https://pubmed.ncbi.nlm.nih.gov/26871536/) prospectively followed a mixed TKA/THA cohort for six months. Preoperative opioid use and other pain-related observations were associated with later opioid use. This does not establish that opioids caused every poor outcome, validate a universal dose threshold, or show that an intraoperative opioid-free regimen prevents persistent use.

[Forsythe et al., 2008, PMID 18719716](https://pubmed.ncbi.nlm.nih.gov/18719716/) examines catastrophizing and residual pain after knee arthroplasty. Prognostic associations should not be converted into a diagnosis, blame, a reason to deny surgery, or proof that a particular screening-directed intervention improves outcomes.

## Reading questions

1. Is the outcome persistent opioid use, pain, function, satisfaction, or another construct?
2. How were baseline exposure, follow-up use, missing data and confounders defined?
3. Does the study support prediction in a comparable population, or only a group association?
4. Has the proposed risk-modification intervention itself been tested?
5. Could structural disease, mood, sleep, widespread pain, medication effects and access to care overlap?

A questionnaire score is not a diagnosis of opioid-induced hyperalgesia, central sensitization or a psychiatric condition. No opioid taper, medication change, screening cutoff or surgical-eligibility rule is supplied. Questionnaire items and copyrighted instruments are not reproduced.