# No long‐term effect of 7‐day computer‐assisted cryotherapy treatment after total knee arthroplasty: A randomized controlled trial with 1‐year follow‐up

## TL;DR

A study found that a 7-day computer-assisted cryotherapy treatment after knee replacement surgery does not provide long-term benefits in pain, function, or satisfaction up to one year later.

## Contribution

This study is the first to investigate the long-term effects of short-term cryotherapy after knee surgery using a randomized controlled trial with a one-year follow-up.

## Key findings

- No significant long-term differences in knee function, pain, or satisfaction between cryotherapy and regular care groups.
- Short-term benefits of cryotherapy may not translate into lasting clinical improvements after one year.
- Non-blinding and lack of objective measures may have influenced the study's outcomes.

## Abstract

Positive effects on pain and opioid use were found in the first post‐operative week, but long‐term effects are unclear. Since rapid recovery studies show that short‐term benefits may have positive long‐term effects, the aim of this study is to investigate if there are any late effects (until 1 year post‐operative) of computer‐assisted cryotherapy (CAC) after total knee arthroplasty (TKA) on knee function, pain and patient satisfaction.

A single‐centre non‐blinded randomized controlled trial was performed, comparing a cryotherapy group and a regular post‐operative care group after TKA. The cryotherapy group used computer‐assisted cooling, with instructions for cooling several hours per day for the first seven post‐operative days. Oxford knee scores (OKS) (0–48), Knee Injury and Osteoarthritis Outcome Score‐Physical function Short form (KOOS‐PS) scores (0–100) and numeric rating scale (NRS) pain scores (0–10) were scored pre‐operative and 6 and 12 months post‐operative. Anchor questions about self‐perceived changes in daily functioning and pain (7‐point Likert scale) and patient satisfaction (NRS, 0–10) were obtained at both post‐operative time points.

A total of 102 patients were analyzed, 51 patients in both groups. OKS showed no significant difference between the cryotherapy and the regular care groups after 6 and 12 months (median 37.0 vs. 38.0 after 6 months and 40.0 for both groups after 12 months, p = 0.634 and p = 0.754). Also, no significant differences were found between groups in KOOS‐PS score, NRS pain score, anchor questions and patient satisfaction.

This study showed that use of CAC for 7 days post‐operative after TKA has no significant late effects (until 1 year post‐operative) on functioning, pain and patient satisfaction. This could imply that the clinical benefits of 7 days of cryotherapy are too short to demonstrate longer‐term effects. Limitations such as non‐blinding and lack of objective outcome measures might have influenced the outcomes.

Therapeutic study with level of evidence I.