Effect of Autologous Expanded Bone Marrow Mesenchymal Stem Cells or Leukocyte-Poor Platelet-Rich Plasma in Chronic Patellar Tendinopathy (With Gap >3 mm): Preliminary Outcomes After 6 Months of a Double-Blind, Randomized, Prospective Study

Abstract

Background: Patellar tendinopathy is common. The success of traditional management, including isometric or eccentric exercises combined with shockwave therapy and even surgery, is limited. Therefore, it is important to determine whether biological treatments such as ultrasound-guided intratendinous and peritendinous injections of autologous expanded bone marrow mesenchymal stem cells (BM-MSCs) or leukocyte-poor platelet-rich plasma (Lp-PRP) improve clinical outcomes in athletic patients with patellar tendinopathy. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: A prospective, double-blinded, randomized, 2-arm parallel group, active controlled, phase 1/2 single-center clinical study was performed in patients who had proximal patellar tendinopathy with a lesion >3 mm. A total of 20 participants (age 18-48 years) with pain for >4 months (mean, 23.6 months) and unresponsive to nonoperative treatments were randomized into 2 groups. Of these, 10 participants were treated with BM-MSC (20 × 106 cells) and 10 with Lp-PRP. Both groups performed the same postintervention rehabilitation protocol. Outcomes included the Victorian Institute of Sport Assessment for pain (VISA-P), self-reported tendon pain during activity (visual analog scale [VAS]), muscle function by dynamometry, tendon thickness and intratendinous vascularity by ultrasonographic imaging and Doppler signal, ultrasound tissue characterization (UTC) echo type changes, and magnetic resonance imaging (MRI) T2-weighted mapping changes. Participants were followed longitudinally for 6 months. Results: The average VAS scores improved in both groups at all time points, and there was a significant reduction in pain during sporting activities ( P < .05). In both groups, the average mean VISA-P scores at 6 months were significantly increased compared with baseline (66 BM-MSC group and 72.90 Lp-PRP group), with no significant differences in VAS or VISA-P scores between the groups. There were statistically significant greater improvements in tendon structure on 2-dimensional ultrasound and UTC in the BM-MSC group compared with the Lp-PRP group at 6 months. Similarly, the BM-MSC group demonstrated significant evidence of restoration of tendon structure on MRI compared with the Lp-PRP group at 6 months. Only the participants in the BM-MSC group showed evidence of normalization of tendon structure, with statistically significant differences between the groups on T2-weighted, fat-saturated sagittal and coronal scans and hypersignal in T2-weighted on spin-echo T2-weighted coronal MRI scan. Both treatments were safe, and no significant adverse events were reported in either group. Conclusion: Treatment with BM-MSC or Lp-PRP in combination with rehabilitation in chronic patellar tendinopathy is effective in reducing pain and improving activity levels in active participants. Participants who received BM-MSC treatment demonstrated greater improvement in tendon structure compared with those who received Lp-PRP. Registration: 2016-001262-28 (EudraCT identifier); NCT03454737 (ClinicalTrials.gov identifier)

Management of patellar tendinopathy: a systematic review and network meta-analysis of randomised studies

“…Online supplemental table 1 shows the characteristics of the included studies 12–48. A total of 37 randomised controlled trials (RCTs) were found to be eligible, including 1332 patients (1407 tendons) with patellar tendinopathy (mean age 29.2 years).…”

Platelet-rich plasma injection in the treatment of patellar tendinopathy: a systematic review and meta-analysis

“…Of these, 12 articles [ 10 , 19 , 26 – 35 ] (Additional file 2 : Table S1) were excluded based on the inclusion and exclusion criteria. Ultimately, eight articles (5 RCTs and 3 non-RCTs; [ 11 , 15 – 18 , 20 – 22 ]) were included in this meta-analysis. The PRISMA flow diagram, including the reasons for exclusion, are illustrated in Fig.…”

“…The sample size of the included studies ranged from 20 to 57 participants. The VAS pain score (7 trials) [ 11 , 15 , 17 , 18 , 20 – 22 ] was used to measure pain relief. The Victorian Institute of Sports Assessment-Patellar questionnaire (6 trials) [ 15 , 16 , 18 , 20 , 22 , 36 ] score was used to measure knee functional activities (knee and sports activities).…”

“…The VAS pain score (7 trials) [ 11 , 15 , 17 , 18 , 20 – 22 ] was used to measure pain relief. The Victorian Institute of Sports Assessment-Patellar questionnaire (6 trials) [ 15 , 16 , 18 , 20 , 22 , 36 ] score was used to measure knee functional activities (knee and sports activities). The QoL was assessed by using the SF-12 score (1 trial) [ 17 ] and EQ-VAS score (1 trial) [ 11 ].…”

Application of Orthobiologics in Achilles Tendinopathy: A Review

“…Improved Achilles tendon rupture scores were observed with autologous BMAC augmentation in Achilles tendon rupture [ 81 ]. 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 ].…”