Combining Fat Tissue Injection with Knee Surgery Shows Lasting Benefits
Andrea Giorgini, Filippo Selleri, Francesco Zambianchi, Giacomo Cataldo, Elena Francioni, Fabio Catani · BMC Musculoskeletal Disorders · 2022
Study tracked 50 knees with moderate-to-severe arthritis
Researchers in Italy followed 49 patients (50 knees) who had significant knee osteoarthritis. All participants had been told they needed knee replacement surgery but chose to try a different approach first. Each patient received arthroscopic surgery combined with a single injection of their own processed fat tissue (called micro-fragmented adipose tissue, or MFAT). The study tracked outcomes for two full years to understand both safety and effectiveness.
All participants had moderate-to-severe arthritis, classified as Kellgren-Lawrence grade III or IV. This is the medical scale doctors use to rate arthritis severity on X-rays. Grades III and IV represent significant joint damage. The average patient age was 57 years, ranging from 39 to 76.
Over 80% of patients achieved meaningful improvement
The results showed that most patients experienced real, noticeable benefits. At the one-year mark, 84% of patients reached what doctors call "minimal clinically important difference" on the KOOS score. This measures pain, symptoms, daily function, sports ability, and quality of life. At two years, 80% still maintained this meaningful improvement.
Similar results appeared on the IKDC score, another widely used knee function measurement. At one year, 74% of patients achieved significant improvement. By two years, this actually increased slightly to 76%. These numbers suggest the treatment provides lasting relief for most patients.
Only eight percent eventually needed knee replacement
During the two-year follow-up period, just four patients (8%) went on to have knee replacement surgery. This is notable because every participant had originally been recommended for knee replacement. The treatment helped most patients delay or avoid this major surgery entirely.
No serious complications occurred from the fat tissue injection or the arthroscopic procedure. This combination approach proved safe across all 50 knees treated. Minor side effects were not detailed, but researchers specifically noted the absence of major adverse events.
Cartilage damage severity affected long-term outcomes
The researchers discovered that patients with the most severe cartilage damage had less favorable results at two years. Those with high-grade cartilage lesions showed statistically significant differences in their IKDC scores and most KOOS measurements compared to patients with less severe damage.
This finding helps doctors identify which patients might benefit most from this treatment. Those with moderate arthritis and less extensive cartilage damage appear to be the best candidates for lasting improvement.
Treatment combined keyhole surgery with regenerative injection
The procedure involved two parts performed during the same operation. First, surgeons used arthroscopy to clean up the joint. This included removing loose debris and smoothing damaged meniscus tissue. Some patients also received micro-drilling to stimulate cartilage repair in small damaged areas.
Second, surgeons injected approximately 7 milliliters of processed fat tissue directly into the knee joint. This tissue was harvested from the patient's own abdomen during the same procedure. The fat was processed using a specialized system that preserves the natural healing properties while creating tiny tissue fragments that can be easily injected.
What this means for your treatment decision
This study adds to growing evidence that micro-fragmented adipose tissue can provide meaningful relief for knee osteoarthritis. The combination with arthroscopic surgery appears safe and effective for most patients with moderate-to-severe disease. However, this was an observational study without a comparison group, so researchers cannot say definitively how much benefit came from the fat injection versus the arthroscopy alone.
If you have significant knee arthritis and want to explore options before committing to joint replacement, this approach may be worth discussing with your doctor. The best candidates appear to be those with moderate arthritis who have not yet developed the most severe cartilage damage.
Source: Giorgini et al., BMC Musculoskeletal Disorders, 2022.
Original Publication
Autologous micro-fragmented adipose tissue associated with arthroscopy in moderate-severe knee osteoarthritis: outcome at two year follow-up
Andrea Giorgini, Filippo Selleri, Francesco Zambianchi, Giacomo Cataldo, Elena Francioni, Fabio Catani · BMC Musculoskeletal Disorders · 2022
This retrospective, single-center study evaluated the efficacy of a single injection of autologous micro-fragmented adipose tissue (aMFAT) combined with arthroscopy in treating moderate-severe knee osteoarthritis. The study included 49 patients (50 knees) with Kellgren-Lawrence grade III-IV knee OA who had previously been indicated for knee replacement but refused surgery. All patients received aMFAT injection and arthroscopic procedures including cartilage debridement, meniscal regularization/selective meniscectomy, or micro-drilling between December 2015 and February 2018. Adipose tissue was harvested from the abdomen and mechanically processed using the Lipogems system before injection. Primary outcomes were assessed using Knee Injury and Osteoarthritis Outcome Score (KOOS) and subjective International Knee Documentation Committee (IKDC) scores at one and two years post-operatively. Results showed that Minimal Clinically Important Difference was achieved by 84% and 74% of patients at one year and 80% and 76% at two years for KOOS and IKDC, respectively. Four patients (8%) underwent knee replacement during follow-up, with no major adverse events reported. High-grade chondral lesions negatively affected outcomes at two years. The study concluded that aMFAT injection associated with arthroscopy is a safe and effective treatment for knee OA, demonstrating substantial clinical improvement without major complications.