Efficacy of Stem Cell Therapy for Tendon Disorders: A Systematic Review

Abstract

Background: Stem cell therapy is an emerging treatment for tendon disorders. Purpose: To systematically review the efficacy of stem cell therapy for patients with tendon disorders. Study Design: Systematic review; Level of evidence, 4. Methods: MEDLINE/PubMed, EMBASE, CINAHL, CENTRAL, PEDro, and SPORTDiscus; trial registers; and gray literature were searched to identify randomized controlled trials (RCTs) and non-RCTs, cohort studies, and case series with 5 or more cases. Studies investigating any type of stem cell therapy for patients with tendon disorders were eligible if they included patient-reported outcome measures or assessed tendon healing. Risk of bias was assessed through use of the Cochrane risk of bias tools. Results: This review included 8 trials (289 patients). All trials had moderate to high risk of bias (level 3 or 4 evidence). In Achilles tendon disorders, 1 trial found that allogenic-derived stem cells led to a faster recovery compared with platelet-rich plasma. Another study found no retears after bone marrow–derived stem cell therapy was used in addition to surgical treatment. There were 4 trials that studied the efficacy of bone marrow–derived stem cell therapy for rotator cuff tears. The controlled trials reported superior patient-reported outcomes and better tendon healing. A further 2 case series found that stem cell therapy improved patient-reported outcomes in patients with patellar tendinopathy and elbow tendinopathy. Conclusion: Level 3 evidence is available to support the efficacy of stem cell therapy for tendon disorders. The findings of available studies are at considerable risk of bias, and evidence-based recommendations for the use of stem cell therapy for tendon disorders in clinical practice cannot be made at this time. Stem cell injections should not be used in clinical practice given the lack of knowledge about potentially serious adverse effects.

Industrial Development of Standardized Fetal Progenitor Cell Therapy for Tendon Regenerative Medicine: Preliminary Safety in Xenogeneic Transplantation

“…Arrays of potential cellular sources have therefore been proposed in tendon bioengineering workflows, comprising various stem cells, placenta cells, amniotic cells, platelet-derivatives, tendon sheath fibroblasts, and adult tenocytes. However, results have been variable and sometimes contradictory [ 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 ]. Recently, cultured primary human fetal progenitor tenocytes (hFPT) have been preliminarily investigated within allogeneic homologous regenerative medicine approaches of tendon ruptures (e.g., hand, Achilles, or rotator cuff tendons) or specific inflammatory diseases.…”

Mesenchymal Stem Cells for Treatment of Tendon and Ligament Injuries-clinical Evidence

“…Two systematic reviews published in 2017 and 2020 documented the positive therapeutic effect of orthobiologics on tendon injuries in humans. Clinical improvement and in some studies structural changes detected by MRI and US were reported ( 31 , 32 ). Positive effects were maintained even 3 to 4 years after the treatment.…”

Application of Orthobiologics in Achilles Tendinopathy: A Review

“…BM-MSCs promote early rehabilitation, lower incidence of re-rupture, improvement of pain scores, and amelioration of tendon structure and strength, without the occurrence of serious complications [ 81 , 82 , 83 , 84 , 85 , 86 , 87 ]. van den Boom et al derived level 4 evidence for BMAC augmentation in Achilles tendon repair in terms of improved PROMs and absence of re-tears in 2.5 years follow-up [ 88 ]. However, more robust data are still required to further support the efficacy and safety regarding the clinical administration of BMA for AT, more specifically.…”