Sleep quality improves after total knee arthroplasty: Addressing early disturbance and risk factors.

OBJECTIVES

Sleep is an important determinant of quality of life. Sleep disturbance is concomitant with end-stage knee osteoarthritis for which total knee arthroplasty (TKA) is the most commonly done procedure. However, literature on this topic is lacking in terms of the impact of sleep quality on patient satisfaction after arthroplasty, especially the adverse associations of surgery on sleep quality. Improvement in sleep quality may be a necessary prerequisite for any effective rehabilitation program. In our study we aim to assess the changes in sleep quality after TKA, and how it affects patient satisfaction of TKA and other quality-of-life indicators, postoperatively.

METHODS

Over a period of two years, 104 patients undergoing primary total knee arthroplasty were assessed prospectively using the Pittsburgh Sleep Quality Index (PSQI), Knee Society Score (KSS), Oxford Knee Score (OKS); preoperatively and postoperatively at 3 months, 6 months, and 1 year. Obesity and diabetes status were also included in the analyses.

RESULTS

Preoperatively, most patients exhibited poor sleep quality (mean PSQI score 9.23 (Standard deviation (SD) ​= ​3.03), which subsequently improved after surgery. Immediately after surgery, there was an initial worsening in the PSQI scores until 6 weeks (12.58 (SD ​= ​3.59)). However, at 1 year, there was a statistically significant improvement to a mean of 5.69 (SD ​= ​1.91). The mean Visual Analogue Scale (VAS) score showed a statistically significant decrease from 7.26 (SD ​= ​1.90) pre-operatively to 1.80 (SD ​= ​1.37) at 1 year postoperatively (p ​< ​0.001). The mean OKS showed a statistically significant increase from preoperative 18.15 to 33.81 at 1 year and the composite KSS increased from 36.22 preoperative to 87.09 at 1 year (p ​< ​0.001). Improvement in sleep was observed for 61% of non-obese patients while obese patients did not observe any improvement in sleep. Only 8% of diabetics showed improved sleep compared to 55% of non-diabetics.

CONCLUSIONS

We observed an overall improvement in sleep quality after total knee arthroplasty. However, there was an initial stage of sleep disturbance immediately postoperatively. Obesity and diabetes may lower the chances of achieving optimal improvements in both functional and sleep outcomes.

LEVEL OF EVIDENCE

Level III.