By Elizabeth Kwon, SPT

Mesenchymal stem cells (MSCs) are a prospective intervention for treating osteoarthritis for the potential of cartilage tissue repair and regenerative ability. MSC therapies primarily work by reducing inflammatory cell properties, expressing anti-inflammatory cell signals, and increasing the activity of cartilage-producing cells. In this randomized controlled trial of 30 participants, researchers specifically aimed to determine if adipose-derived mesenchymal stem cell (ADMSC) therapy was a safe and effective intervention for decreasing pain, improving function, and modifying the progression of disease in patients with moderate knee OA.

  • Patients were randomly allocated into either a single or double injection treatment group or a control group. Injections were given at baseline and at 6 months for the two-injection group. The control group underwent conservative management, including analgesics, weight management, and exercise.
  • Patients were on average in their early to mid 50’s, had moderate (grade II-III) knee OA in one leg.
  • Outcome measurements were recorded at 1, 3, 6 and 12 months follow-up using the Numeric Pain Rating Scale (NPRS), Knee Injury and Osteoarthritis Outcome Measures Scale (KOOS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), MRI, and the MRI Osteoarthritis Knee Score (MOAKS).
  • The effectiveness of ADMSC treatment on pain and function
    • Both single and double injection groups had significantly improved pain scores on the NPRS and KOOS subscales compared to conservative management at 12 months
    • Both single and double injection groups had significantly improved function on the WOMAC and KOOS subscales compared to conservative management at 12 months
    • Comparing single and double injection groups, neither had a more significant effect than the other for pain and function, but the single injection group generally also had significant improvements over the control group at 3 and 6 months.
  • Minimal clinically important differences at 12-month follow-up were achieved on average in 84.1% of subjects in the single injection group, 87.1% in the double injection group, and 25.7% in the control group
  • The effectiveness of ADMSC treatment on disease progression at 12-month follow-up
    • The two-injection group had the greatest improvements in cartilage or the prevention of progressive of cartilage loss (89%) as well as prevention of osteophyte formation (89%) suggesting it may assist with the stabilization of knee OA
    • In comparison, the single-injection group was able to improve or prevent degradation of cartilage in 70% of subjects; however, 50% of subjects experienced a progression of osteophyte formation.
  • Limitations of the study include:
    • sample size may or may not have been sufficient
    • starting BMI between the three groups were significantly different potentially affecting the results
    • some subjects experienced pain and swelling after the second injection at 6 months potentially altering results of the two-injection group

In conclusion, ADMSC is a promising treatment for osteoarthritis that is being currently researched. This study demonstrates that ADMSC is safe and effective at reducing pain, improving function, and moderating disease progression for those with moderate knee OA. Differences between the effectiveness of one versus two injections can be debated as the one-injection group experienced more significant changes at 3 and 6 months, but the two-injection group saw a greater number of subjects with minimal clinically important difference and stabilization of OA. At Physical Therapy First, your physical therapist can discuss MSC and other alternative treatments for your knee osteoarthritis to determine if you are a potential candidate to benefit from ADMSC, as well as provide you with other conservative rehabilitative interventions.

Freitag, Julien. Bates, Dan. Wickham, James. Shah, Kiran. Huguenin, Leesa, Tenen, Abi. Paterson, Kade. Boyd, Richard. Adipose-derive mesenchymal stem cell therapy in the treatment of knee osteoarthritis: a randomized controlled trial. Regenerative Medicine 2019; 14 (3), 213-230.