Analgesic use may not decrease in the first postoperative year in patients underwent total knee arthroplasty due to advanced osteoarthritis

Background

Total knee arthroplasty (TKA) is expected to relieve pain and reduce the use of analgesics in patients with advanced knee osteoarthritis. However, in some cases, there is no relief in the pain of the patients and the use of analgesics continues. The aim of this study was to compare analgesic consumption one year before and after TKA in the same patient group and to evaluate whether there is a decrease in analgesic consumption after TKA.

Method

The cumulative amounts of analgesia used by the patients in the one-year periods before and after the operation were checked from the automated patient records system and the national systems showing drug prescriptions. The dosages of all the analgesics used in the one-year periods before and after the operation were calculated and converted to oral morphine equivalents (OME). The demographic data of the patients, cumulative OME and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were used in the assessment.

Results

It was observed that there was a statistically significant improvement in Womac scores after the treatment compared to the pre-treatment. Although the mean amount of analgesics decreased compared to pre-treatment, it was not statistically significant. Also, age and preoperative analgesic use were found to be the two most important factors in relation to total postoperative analgesic consumption.

Conclusion

The results of this study indicate that there may not be a substantial reduction in the use of analgesic by patients within the first year after TKA. Furthermore, the age and preoperative analgesic use were identified as the two primary factors influencing postoperative analgesic consumption.

Level of evidence

Retrospective Cohort Study.