Microfragmented adipose tissue injection reduced pain compared to a saline control among patients with symptomatic knee osteoarthritis during one-year follow-up: a randomized, controlled trial

Arthroscopy. 2024 Sep 5:S0749-8063(24)00639-X. doi: 10.1016/j.arthro.2024.08.037. Online ahead of print.

Abstract

Purpose: To evaluate the effectiveness of microfragmented adipose tissue (MFAT) for pain relief and improved joint functionality in knee OA in a randomized, controlled clinical trial with 1-year follow-up.

Methods: Seventy-five patients were stratified by baseline pain level, and randomized to one of three treatment groups: MFAT, corticosteroid (CS), or saline control (C) injection. Patients 18 years of age or older, diagnosed with symptomatic knee osteoarthritis, with radiographic evidence of knee osteoarthritis and a visual analog pain scale (VAS) score of 3/10 or greater were included. Patients were excluded if they had any prior intra-articular knee injection, current knee ligamentous instability or an allergy to lidocaine/corticosteroid. The VAS pain scale, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Knee Injury and Osteoarthritis Outcome score (KOOS) were recorded pre-procedure and at 2 weeks, 6 weeks, 3 and 6 months, and 1 year follow-up.

Results: MFAT demonstrated consistent and statistically significant improvements across all primary outcome measures for joint pain and functionality compared to C. For MFAT, there was a significant improvement over baseline at each follow-up, with median (95% CI) KOOS Pain score changes of 18.1 (11.1, 26.4) at week 2 to 27.8 (19.4, 37.5) at 1 year. For CS, the median KOOS pain score reached a maximum of 22.2 (15.3, 30.6) at week 2, only to level off to 13.9 (-2.8, 29.2), a level not statistically different from baseline, at 1 year. The median changes for C hovered around 6-11 points, with statistically significant improvements over baseline indicating a placebo effect. Similar trends were seen for the WOMAC Pain score and VAS Pain score.

Conclusions: In this study, MFAT demonstrated a clinically significant improvement in primary outcome scores compared with a saline control group, while the corticosteroid group only showed statistically significant improvement compared to the control group at 2 and 6 weeks. This finding indicates that MFAT may be a viable alternative treatment for patients with knee OA that fall into the orthopaedic treatment gap.

Keywords: autologous adipose tissue; knee osteoarthritis; mesenchymal stem cells; microfragmented fat.