App helps patients cut opioid use after knee replacement

App users took 23.2% fewer opioids and 14.6% more paracetamol than the control group.

Older person using smartphone

Patients who underwent knee replacement who used an app to monitor their analgesic use had better pain control and took fewer opioids post surgery, study results show[1]

The trial included 71 patients undergoing total knee replacement who were randomly assigned to the app or usual care. The app allowed patients to input their pain level and advised them on use of pain medicines and whether to rest or exercise.

During the period from discharge to two weeks’ after the operation, those assigned to the app used 23.2% fewer opioids and 14.6% more paracetamol than the control group. Some 19 patients (50%) in the app group were considered active users (≥12 app uses); these patients used 44.3% fewer opioids than the control group and had a faster improvement in pain at night and during activities.

The researchers said that given the low opioid use in the study (mean 0.4 tablets/day), the effects may be more pronounced in a population with greater opioid use.

“These are important findings given the current demands on the healthcare system and the growing misuse of prescription painkillers worldwide,” concluded Amar Sheombar, a study author and anaesthesiologist and pain specialist from Kliniek ViaSana, an orthopaedic clinic in Mill, the Netherlands.


[1] Pronk Y, Peters M, Sheombar A et al. Improved pain control and reduce opiate use after TKR using a mobile e-health app. Euroanaesthesia, Vienna, 1–3 June 2019. Abstract available at: (accessed July 2019)

Last updated
The Pharmaceutical Journal, July 2019;Online:DOI:10.1211/PJ.2019.20206749