Cord Blood Stem Cells for Knee Osteoarthritis: New Hope

A systematic review published in the Orthopaedic Journal of Sports Medicine (2022) provides compelling evidence for the efficacy of human umbilical cord–derived mesenchymal stem cells (hUC-MSCs) in treating knee osteoarthritis (OA), offering significant pain relief and functional improvement.
 

Purpose and Methods

The study, led by Dhillon et al., aimed to evaluate hUC-MSCs' effectiveness in alleviating knee OA symptoms. Following PRISMA guidelines, researchers searched PubMed, Embase, and Cochrane Library up to January 20, 2021 for “umbilical cord knee osteoarthritis,” including seven studies (levels of evidence 1–4) involving 385 patients (mean age 59.7 years, 43.2% male) with a minimum 6-month follow-up. Outcomes were assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, subjective International Knee Documentation Committee (IKDC) score, and macroscopic International Cartilage Regeneration & Joint Preservation Society (ICRS) score. hUC-MSCs, sourced from umbilical cord blood or Wharton’s jelly, were administered via intra-articular injections or surgical implantation. Risk of bias was evaluated using ROBINS-I for nonrandomized studies and the Cochrane tool for one randomized trial.
 

Key Findings

Over a mean follow-up of 23.4 months, hUC-MSC treatment yielded significant clinical improvements. Weighted averages showed WOMAC scores improved from 39.3 to 11.0, IKDC from 40.9 to 67.3, VAS from 50.7 to 17.7, and ICRS from 4.0 to 1.8. Four of five studies reported statistically significant WOMAC improvements (p<0.05), two of four for IKDC and VAS, and all three ICRS-assessing studies indicated enhanced cartilage repair, though P-values were unreported. No severe adverse effects were noted, with only transient swelling or pain in some cases. Patients with milder OA (Kellgren-Lawrence grades 1–3) and those receiving higher cell doses showed greater benefits.
 

Implications

This review underscores hUC-MSCs’ potential as a safe, effective therapy for knee OA, supporting cartilage repair and symptom relief. However, further randomized trials are needed to compare hUC-MSCs with other treatments and assess long-term outcomes. These findings highlight the value of stem cell therapies, reinforcing the importance of cord blood and tissue banking for future medical applications.