Effect of platelet-rich plasma on the degenerative rotator cuff tendinopathy according to the compositions

Biologics in rotator cuff repair

Rotator cuff tears are common in middle-aged and elderly patients. Despite advances in the surgical repair of rotator cuff tears, the rates of recurrent tear remain high. This may be due to the complexity of the tendons of the rotator cuff, which contributes to an inherently hostile healing environment. During the past 20 years, there has been an increased interest in the use of biologics to complement the healing environment in the shoulder, in order to improve rotator cuff healing and reduce the rate of recurrent tears. The aim of this review is to provide a summary of the current evidence for the use of forms of biological augmentation when repairing rotator cuff tears.

Effectiveness of platelet-rich plasma in partial-thickness rotator cuff tears: a systematic review

IMPORTANCE

Partial-thickness rotator cuff tears (PTRCTs) commonly affect overhead athletes, leading to a decline in sports performance. Platelet-rich plasma (PRP) is being explored as an alternative treatment modality for individuals with PTRCTs to reduce discomfort and enhance functional recovery. We conducted a systematic review study of randomized controlled clinical trials to determine the effectiveness of PRP in treating PTRCTs.

AIM

To determine the effectiveness of PRP in treating PTRCTs.

EVIDENCE REVIEW

We conducted a comprehensive literature search for randomized controlled trials (RCTs) that compared the effectiveness of PRP with eccentric exercise and placebo injections as treatments for PTRCTs. We searched databases such as the Cochrane Library, Web of Science, PubMed, and EMBASE. The visual analog scale (VAS) score, American Shoulder and Elbow Surgeon (ASES) score, and Constant-Murley Score (CMS) was utilized as an outcome measure. Statistical analysis was performed using RevMan 5.3 software.

FINDINGS

Our meta-analysis included 12 studies involving 762 patients. At six weeks post-treatment, the PRP group had significantly higher VAS scores compared to the control group, indicating improvement (standard mean difference (SMD): -2.04 [95% confidence interval (CI): -4.00 to -0.08], I2 ​= ​97%, P-value ​= ​0.04). Patients who received PRP showed statistically significant improvements in VAS scores at 3 months and 6 months follow-up (SMD, -1.78 [95% CI: -3.03 to -0.52], I2 ​= ​96%, P-value ​= ​0.005) (SMD: -2.26 [95% CI: -3.77 to -0.76], I2 ​= ​97%, P-value ​= ​0.003). A statistically significant difference was also observed in VAS scores at the long-term 1-year follow-up (SMD: -2.27 [95% CI: -4.07 to -0.47]; I2 ​= ​98%; P-value ​= ​0.031). There were statistically significant differences in ASES scores and CMS scores in the short-term (SMD: 1.21 [95% CI: 0.19 to 2.24], I2 ​= ​96%, P-value ​= ​0.02) (SMD, 2.01 [95% CI: 0.14 to 3.88], I2 ​= ​97%, P-value ​= ​0.04). However, in the long-term ASES and CMS scores did not show any statistical significance (SMD: 2.06 [95% CI: -0.54 to 4.65], I2 ​= ​99%, P-value ​= ​0.12) (SMD: 4.36 [95% CI: -5.48 to 14.21], I2 ​= ​99%, P-value ​= ​0.39).

CONCLUSIONS AND RELEVANCE

Our findings suggest that PRP treatment is effective in reducing pain for individuals with PTRCTs, providing benefits in the short and long term. However, its impact on functional recovery appears somewhat constrained and doesn't endure over time. Additionally, significant heterogeneity exists among studies, encompassing variations in PRP composition and control group treatments. Consequently, we conclude that compelling evidence for symptom improvement in PTRCT patients following PRP treatment remains elusive.

LEVEL OF EVIDENCE

Level I.

One-shot platelet-rich plasma (PRP) injection is non-inferior to extracorporeal shockwave therapy in the management of supraspinatus tendinosis

PURPOSE

Supraspinatus tendinosis (ST) refers to the intratendinous degeneration of the supraspinatus tendon. Platelet-Rich Plasma (PRP) is one of the possible conservative treatments for supraspinatus tendinosis. This prospective observational study aims to evaluate the efficacy and safety of a single ultrasound-guided PRP injection in the treatment of supraspinatus tendinosis and to assess its non-inferiority to the widely used shockwave therapy.

METHODS

Seventy-two amateur athletes (35 male, mean age: 43.75 ± 10.82, range 21-58 years old) with ST were finally included in the study. All the patients underwent clinical evaluation at baseline, (T0) and at 1-month (T1), 3-month (T2) and 6-month (T3) follow-up using the following clinical scales: the Visual Analogue Scale for pain (VAS), Constant Score and the Disabilities of the Arm, Shoulder and Hand Score (DASH). A T0 and T3 ultrasound examination was also performed. The findings observed in the recruited patients were compared to the clinical results observed in a retrospective control group made up of 70 patients (32 male, mean age = 41.29 ± 13.85, range 20-65 years old) treated by extracorporeal shockwave therapy (ESWT).

RESULTS

VAS, DASH and Constant scores significantly improved from T0 to T1; the improvement in clinical scores was kept until T3. No local nor systemic adverse events were observed. An improvement in the tendon structure was observed on ultrasound examination. PRP showed a non-statistical inferiority, in terms of efficacy and safety, compared to ESWT.

CONCLUSION

The PRP one-shot injection is a valid conservative treatment to reduce pain, and improve both quality of life and functional scores in patients with supraspinatus tendinosis. Furthermore, the PRP intratendinous one-shot injection showed a non-inferiority in terms of efficacy at the 6-month follow-up, compared to ESWT.

Exercise therapy for tendinopathy: a mixed-methods evidence synthesis exploring feasibility, acceptability and effectiveness

Background

Tendinopathy is a common, painful and functionally limiting condition, primarily managed conservatively using exercise therapy.

Review questions

(i) What exercise interventions have been reported in the literature for which tendinopathies? (ii) What outcomes have been reported in studies investigating exercise interventions for tendinopathy? (iii) Which exercise interventions are most effective across all tendinopathies? (iv) Does type/location of tendinopathy or other specific covariates affect which are the most effective exercise therapies? (v) How feasible and acceptable are exercise interventions for tendinopathies?

Methods

A scoping review mapped exercise interventions for tendinopathies and outcomes reported to date (questions i and ii). Thereafter, two contingent systematic review workstreams were conducted. The first investigated a large number of studies and was split into three efficacy reviews that quantified and compared efficacy across different interventions (question iii), and investigated the influence of a range of potential moderators (question iv). The second was a convergent segregated mixed-method review (question v). Searches for studies published from 1998 were conducted in library databases (n = 9), trial registries (n = 6), grey literature databases (n = 5) and Google Scholar. Scoping review searches were completed on 28 April 2020 with efficacy and mixed-method search updates conducted on 19 January 2021 and 29 March 2021.

Results

Scoping review - 555 included studies identified a range of exercise interventions and outcomes across a range of tendinopathies, most commonly Achilles, patellar, lateral elbow and rotator cuff-related shoulder pain. Strengthening exercise was most common, with flexibility exercise used primarily in the upper limb. Disability was the most common outcome measured in Achilles, patellar and rotator cuff-related shoulder pain; physical function capacity was most common in lateral elbow tendinopathy. Efficacy reviews - 204 studies provided evidence that exercise therapy is safe and beneficial, and that patients are generally satisfied with treatment outcome and perceive the improvement to be substantial. In the context of generally low and very low-quality evidence, results identified that: (1) the shoulder may benefit more from flexibility (effect sizeResistance:Flexibility = 0.18 [95% CrI 0.07 to 0.29]) and proprioception (effect sizeResistance:Proprioception = 0.16 [95% CrI -1.8 to 0.32]); (2) when performing strengthening exercise it may be most beneficial to combine concentric and eccentric modes (effect sizeEccentricOnly:Concentric+Eccentric = 0.48 [95% CrI -0.13 to 1.1]; and (3) exercise may be most beneficial when combined with another conservative modality (e.g. injection or electro-therapy increasing effect size by ≈0.1 to 0.3). Mixed-method review - 94 studies (11 qualitative) provided evidence that exercise interventions for tendinopathy can largely be considered feasible and acceptable, and that several important factors should be considered when prescribing exercise for tendinopathy, including an awareness of potential barriers to and facilitators of engaging with exercise, patients' and providers' prior experience and beliefs, and the importance of patient education, self-management and the patient-healthcare professional relationship.

Limitations

Despite a large body of literature on exercise for tendinopathy, there are methodological and reporting limitations that influenced the recommendations that could be made.

Conclusion

The findings provide some support for the use of exercise combined with another conservative modality; flexibility and proprioception exercise for the shoulder; and a combination of eccentric and concentric strengthening exercise across tendinopathies. However, the findings must be interpreted within the context of the quality of the available evidence.

Future work

There is an urgent need for high-quality efficacy, effectiveness, cost-effectiveness and qualitative research that is adequately reported, using common terminology, definitions and outcomes.

Study registration

This project is registered as DOI: 10.11124/JBIES-20-00175 (scoping review); PROSPERO CRD 42020168187 (efficacy reviews); https://osf.io/preprints/sportrxiv/y7sk6/ (efficacy review 1); https://osf.io/preprints/sportrxiv/eyxgk/ (efficacy review 2); https://osf.io/preprints/sportrxiv/mx5pv/ (efficacy review 3); PROSPERO CRD42020164641 (mixed-method review).

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) HTA programme and will be published in full in HTA Journal; Vol. 27, No. 24. See the NIHR Journals Library website for further project information.

Role of platelet-rich plasma in the treatment of rotator cuff tendinopathy

Shoulder pain is a common musculoskeletal complaint, and rotator cuff (RC) pathologies are one of the main causes. The RC undergoes various tendinopathic and avascular changes during the aging process. Other degenerative changes affecting its healing potential make it an appealing target for biological agents. Platelet-rich plasma (PRP) has demonstrated the potential to deliver a high concentration of several growth factors and anti-inflammatory mediators, and its clinical use is mainly supported by experiments that demonstrated its positive effect on muscle, ligaments, and tendinous cells. This review aimed to specify the role of PRP and its future applications in RC tendinopathies based on the current clinical evidence. Due to the different characteristics and conflicting outcomes, clinicians should use PRP with moderate expectations until more consistent evidence is available. However, it is reasonable to consider PRP in patients with contraindications to corticosteroid injections or those with risk factors for inadequate healing. Its autologous origin makes it a safe treatment, and its characteristics make it a promising option for treating RC tendinopathy, but the efficacy has yet to be established.

Cocktail-like gradient gelatin/hyaluronic acid bioimplant for enhancing tendon-bone healing in fatty-infiltrated rotator cuff injury models

The regeneration of enthesis tissue (native tendon-bone interface) at the post-surgically repaired rotator cuff remains a challenge for clinicians, especially with the emergence of degenerative affection such as fatty infiltration that exacerbate poor tendon-bone healing. In this study, we proposed a cocktail-like hydrogel with a four-layer structure (BMSCs+gNC@GH) for enhancing fatty infiltrated tendon-bone healing. As collagen and hyaluronic acid are the main biomacromolecules that constitute the extracellular matrix of enthesis tissue, this hydrogel was composed of UV-curable gelatin/hyaluronic acid (GelMA/HAMA) dual network gel (GH) with nanoclay (NC) and stem cells loaded. The results showed that NC exhibited a cocktail-like gradient distribution in GH, which effectively mimicked the structure of native enthesis and supported the long-term culture and encapsulation of BMSCs. What's more, the gradient variation of NC provided a biological signal for promoting gradient osteogenic differentiation of cells. Based on the in vivo results, BMSCs+gNC@GH effectively promoted fibrocartilage layer regeneration at the tendon-bone interface and inhibited fatty infiltration. Therefore, BMSCs+gNC@GH group exhibited better biomechanical properties. Thus, this cocktail-like implant may be a promising tissue-engineered scaffold for tendon-bone healing, and it provides a new idea for the development of scaffolds with the function of inhibiting degeneration.

Effects of adjuvant application of corticosteroid and ozone after ultrasound-guided puncture and lavage for the treatment of rotator cuff calcific tendinitis: study protocol for a non-inferiority randomized controlled trial

BACKGROUND

Steroid injection after percutaneous irrigation of calcific deposits is a common method for the treatment of rotator cuff calcific tendinitis (RCCT). However, steroids may prevent calcification resorption and cause potentially irreversible damage to tendons. Recent studies have confirmed the positive effects of ozone injection in shoulder tendinopathies, but no RCCTs have been reported. Thus, our study aims to evaluate the non-inferiority of ozone versus steroid injection.

METHODS

This is a prospective, randomized, parallel control and non-inferiority trial. A total of 100 patients with unilateral symptomatic RCCT will be enrolled and randomized in a 1:1 ratio to two groups: ultrasound-guided injection with ozone or corticosteroid. The primary outcome is the numeric rating scale for pain (NRS) at 1 week and 3 months following the procedure. Secondary outcomes include a multi-dimensional evaluation of shoulder disability and quality of life improvement, the degree of calcification absorption after treatment, and the number of multiple treatments.

DISCUSSION

The results of this study will provide short-term and long-term evidence for the effectiveness of ozone treatment in RCCT in relieving pain or improving shoulder function.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2200063469. Registered on 7 September 2022.

The Effect of Ultrasound-Guided Treatment of Symptomatic Partial Rotator Cuff Injury Under the Background of Deep Learning

Deep learning is one of the most powerful machine learning algorithms at present. The convolutional neural network model has the ability to automatically learn features, and has a greater performance advantage than other deep learning models in the field of image processing. Based on deep learning, the effects of platelet-rich plasma injection of betamethasone on shoulder pain and function in patients with partial rotator cuff injury were investigated. Eighty patients with tendinosis or a partial tear (<1.0 cm) were recruited between 2021 and 2022. Mixed injection of 1 mL betamethasone and 5 mL lidocaine, following 5 mL PRP injected in 7-day intervals, were infiltrated directly into the lesion of supraspinatus interstitial RCT under ultrasound control. The patients were assessed by the SPADI, CMS and ASES before and 1, 3, 6, 9 months after injection. MRI was also performed before and 6 months after injection. All patients had significant better ASES, SST, CMS score and improvement of motion and pain relief after PRP injection, compared with the baseline before injection (p < 0.05). In the MRI data, statistical pre- and post-comparisons revealed significant differences between location of partial rupture and grade of tendinopathy. There were no mortality and major complications observed during follow-up. Under the background of deep learning, ultrasound-guided injection of PRP with betamethasone can progressively relieve shoulder joint pain and improve motor function in patients with partial rotator cuff injury. Ultrasound-guided injection of PRP with betamethasone is safe and useful for rotator cuff disease.

Collagen and platelet-rich plasma in partial-thickness rotator cuff injuries. Friends or only indifferent neighbours? Randomised controlled trial

BACKGROUND

Partial-thickness rotator cuff injuries (PTRCI) are the sum of degenerative, overload, and microtrauma processes. An external supply of collagen and platelet-rich plasma (PRP) could potentially counteract the deterioration of degenerative tendinopathy. This study aimed to compare the effectiveness of collagen with PRP, PRP alone, and collagen alone in the treatment of PTRCI.

METHODS

Ninety patients with PTRCI were randomised and treated with ultrasound-guided injections into the shoulder bursa every consecutive week: Group A - collagen with PRP (n = 30), Group B - collagen alone (n = 30), and Group C - PRP alone (n = 30). Primary outcomes were pain intensity measured in control points on a numeric rating scale (NRS), QuickDash, and EQ-5D-5L questionnaires at the initial assessment (IA) and control assessments after 6 (T1), 12 (T2), and 24 (T3) weeks, respectively.

RESULTS

No statistical differences were found between groups in primary outcomes, although there was a trend towards improvement in Groups A and C (opposite to Group B) between T2 and T3. The following parameters were also observed: rotator cuff discontinuity (n = 3, one case in each group) and rotator cuff regeneration (n = 22 in Group A, n = 20 in Group B, and n = 23 in Group C).

CONCLUSIONS

Combined therapy of collagen and PRP in PTRCI presents similar effectiveness to monotherapies with collagen or PRP.

TRIAL REGISTRATION

The study was prospectively registered on the NCT Trial Center (identification number: NCT04492748 ) on 30.07.2020.

An Open-Labeled Randomized Prospective Multi-center Study to Evaluate the Efficacy and Safety of Intra-articular Injection of OSSINEXT™, an Autologous Growth Factor Concentrate (AGFC) Compared to Hyaluronic Acid (HA) in Knee Osteoarthritis

BACKGROUND

Osteoarthritis (OA) is known as degenerative arthritis and is the second most common rheumatologic problem with a prevalence of 22%-39% in India. Knee OA (KOA) is a major cause of mobility impairment, particularly among females. Non-surgical treatment options for KOA include intra-articular injections of platelet-rich plasma (PRP) and hyaluronic acid (HA). Most commercially available PRP preparation kits do not remove RBCs and WBCs which are detrimental to the healing effects. Wockhardt Regenerative Pvt. Ltd., Mumbai, India has developed a kit known as Ossinext™ which has an advantage over traditional PRP in that it eliminates RBCs and WBCs. This study was conducted to evaluate the effectiveness and safety of intra-articular injection of Wockhardt's Ossinext™ an autologous growth factor concentrate (AGFC) versus HA in KOA.

METHODS

 Male and female patients in the age group between 30 and 75 years with confirmed KOA on radiological assessment with Grades I-III on the Kellgren-Lawrence Grading Scale and with visual analog scale (VAS) pain score of 4 or more (on the numeric rating scale) in spite of taking non-steroidal anti-inflammatory drugs (NSAIDs) since past 2 weeks were considered for study participation. This was an open-labeled study and eligible patients were randomly allocated to AGFC or HA in a 1:1 fashion. Three intra-articular injections were given in the affected knee joint, i.e. at baseline, month 1, and month 2 visits. Patients were evaluated at regular intervals, i.e. at months 5, 8, and 11 for primary and secondary endpoints. The primary efficacy endpoint for this study was change from baseline in WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) scores at month 11 whereas the secondary efficacy endpoints were change from baseline of VAS pain scale at months 1, 2, 5, 8, and 11 as well as change from baseline of WOMAC, KOOS (Knee and Osteoarthritis Outcome System), and IKDC (International Knee Documentation Committee) scale at month 5, 8, and 11. For analysis a mixed model for repeated measures was used.

RESULTS

 Out of the 100 patients who were enrolled, 50 patients each were randomized to AGFC and HA arm. The results were analyzed from 99 patients (49 for AGFC and 50 for HA) who met the criteria for the modified intent to treat (mITT) population. At month 11 on the WOMAC scale, there was greater improvement seen with Ossinext™ compared to HA group which was also statistically significant with p-value of 0.0332. Within the group, there was statistically significant improvement before and after treatment in all scales, i.e. WOMAC, KOOS, IKDC, and VAS at all time points, i.e. months 5, 8, and 11 with a p-value as low as <0.0001. Within the group, the VAS score showed statistically significant improvement even at months 1 and 2 as well. A total of 24 patients reported 37 adverse events (AEs) during the study, most common being pain, pyrexia and swelling but none of the AEs reported during the study were considered as severe in intensity. There were no safety concerns reported.

CONCLUSIONS

In conclusion, greater and statistically significant improvement was seen with Ossinext™ in WOMAC scores at month 11 compared to HA. Ossinext™ also showed marked statistically significant improvement from before treatment to after treatment in the WOMAC, KOOS, IKDC, and VAS scales used for the assessment of KOA with a p-value as low as <0.0001. Ossinext™ was also safe and well-tolerated.

Effectiveness of Lateral Elbow Tendinopathy Treatment Depends on the Content of Biologically Active Compounds in Autologous Platelet-Rich Plasma

Autologous platelet-rich plasma (PRP) injection is an alternative treatment option for patients with lateral elbow tendinopathy. The treatment is supposed to accelerate tissue regeneration by providing high concentrations of growth factors derived from platelets. The aim of the study was to assess the relationship between the content of biologically active compounds in PRP and the clinical effect of the treatment. Thirty patients with lateral elbow tendinopathy treated with a single PRP injection, were evaluated. The pain intensity (measured by a visual analogue scale (VAS)), the pressure pain threshold (PPT), the grip strength and strength of the main arm and forearm muscle groups, and the functional outcome (measured by the Disability of Arm, Shoulder and Hand (DASH) and Patient-Rated Tennis Elbow Evaluation (PRTEE) questionnaires), were assessed before PRP injection and at one- and three-months follow-up. Flow cytometry measurements of the growth factors and inflammatory cytokines in PRP were performed, and the results were used to establish the relationship between those molecules and the clinical outcome. After three months from the intervention, the minimal clinically important difference in pain reduction and functional improvement was observed in 67% and 83% of patients, respectively. Positive correlations were found between the extent of pain reduction after three months and concentrations in the PRP of platelets, epidermal growth factor (EGF), vascular endothelial growth factor, and platelet-derived growth factors. The concentration of EGF in the PRP significantly correlated with an improvement in grip strength, strength of wrist extensors, and the size of functional improvement measured by the PRTEE. The local injection of PRP is a safe and effective treatment option for lateral elbow tendinopathy, and the clinical outcome is correlated with concentrations of its biologically active compounds.

Cell therapies for chondral defects of the talus: a systematic review

Background

This systematic review investigated the efficacy and safety of surgical procedures augmented with cell therapies for chondral defects of the talus.

Methods

The present systematic review was conducted according to the 2020 PRISMA guidelines. PubMed, Google scholar, Embase, and Scopus databases were accessed in March 2022. All the clinical trials investigating surgical procedures for talar chondral defects augmented with cell therapies were accessed. The outcomes of interest were to investigate whether surgical procedures augmented with cell therapies promoted improvement in patients reported outcomes measures (PROMs) with a tolerable rate of complications.

Results

Data from 477 procedures were retrieved. At a mean follow-up of 34.8 ± 9.7 months, the Visual Analogic Scale (VAS) improved of 4.4/10 (P = 0.002) and the American Orthopaedic Foot and Ankle Score (AOFAS) of 31.1/100 (P = 0.0001) points. No improvement was found in Tegner score (P = 0.4). Few articles reported data on complications. At last follow-up, the rate of reoperation and failure were 0.06% and 0.03%, respectively. No graft delamination or hypertrophy was observed.

Conclusion

The current evidence suggests that cell therapies may be effective and safe to enhance surgical procedures for chondral defects of the talus. These results should be considered within the limitations of the present study. The current literature should be enriched with randomized controlled clinical trials with larger population size and longer follow-up.

Leukocyte-Rich Platelet-Rich Plasma Has Better Stimulating Effects on Tenocyte Proliferation Compared With Leukocyte-Poor Platelet-Rich Plasma

Background:

Rotator cuff (RC) tendinopathy is one of the most common causes of shoulder pain. Platelet-rich plasma (PRP) has been frequently used in clinical scenarios, but its efficacy remains inconsistent.

Purpose:

To investigate the different responses of human tenocytes from torn RCs to leukocyte-rich PRP (LR-PRP) and leukocyte-poor PRP (LP-PRP) in a 2-chamber coculture device.

Study Design:

Controlled laboratory study.

Methods:

PRP was prepared using different platelet and leukocyte concentrations according to 5 groups: (1) LR-PRP with 5000 platelets/µL, (2) LR-PRP with 10,000 platelets/µL, (3) LP-PRP with 5000 platelets/µL, (4) LP-PRP with 10,000 platelets/µL, and (5) control with only culture medium supplementation and without PRP stimulation. Platelet-derived growth factor–AB (PDGF-AB) and transforming growth factor–β1 (TGF-β1) were measured in LR-PRP and LP-PRP via enzyme-linked immunosorbent assay. Microscopy, water-soluble tetrazolium salt assay, and quantitative real-time polymerase chain reaction were used to investigate the morphology, proliferation, and gene expression of RC tenocytes exposed to different PRP formulations. Data were collected from at least 3 independent measurements. The results were analyzed via 1-way analysis of variance, followed by the post hoc Bonferroni test.

Results:

The ratio of leukocytes to 5000 platelets/µL was 29.5 times higher in LR-PRP than in LP-PRP (P < .05). In the 5000 platelets/µL groups, the levels of TGF-β1 and PDGF-AB were both significantly higher in LR-PRP versus LP-PRP (TGF-β1: 367.0 ± 16.5 vs 308.6 ± 30.3 pg/mL, respectively [P = .043]; PDGF-AB: 172.1 ± 1.8 vs 94.1 ± 4.2 pg/mL, respectively [P < .001]). Compared with the control group, RC tenocyte proliferation was 1.42 ± 0.01 and 1.41 ± 0.03 times higher in the LR-PRP groups with 5000 platelets/µL and 10,000 platelets/µL, respectively (P < .05). The expression of tenocyte-related genes was higher in tenocytes cultured in LR-PRP.

Conclusion:

Both the LR-PRP groups with 5000 platelets/µL and 10,000 platelets/µL induced more growth factor release and increased RC tenocyte proliferation than did the LP-PRP groups.

Clinical Relevance:

In RC repair, LR-PRP may be better than LP-PRP for increasing the proliferation of tenocytes.

Effects of leukocyte-rich platelet-rich plasma and leukocyte-poor platelet-rich plasma on the healing of bone-tendon interface of rotator cuff in a mice model

Platelet-rich plasma (PRP) is widely used clinically to treat tendon injuries, and often contains leukocytes. However, the debate regarding the concentration of leukocytes in PRP is still ongoing. This study aimed to evaluate the therapeutic effects of leukocyte-rich platelet-rich plasma (LR-PRP) and leukocyte-poor platelet-rich plasma (LP-PRP) on the healing of the bone-tendon interface (BTI) of the rotator cuff. A total of 102 C57BL/6 mice were used. Thirty mice were used to prepare the PRP, while 72 underwent acute supraspinatus tendon injury repair. The animals were then randomly assigned to three groups: LR-PRP, LP-PRP and control groups. The mice were euthanized at 4 and 8 weeks postoperatively, and histological, immunological and biomechanical analyses were performed. The histological results showed that the fusion effect at the bone-tendon interface at 4 and 8 weeks after surgery was greater in the PRP groups and significantly increased at 4 weeks; however, at 8 weeks, the area of the fibrocartilage layer in the LP-PRP group increased significantly. M2 macrophages were observed at the repaired insertion for all the groups at 4 weeks. At 8 weeks, M2 macrophages withdrew back to the tendon in the control group, but some M2 macrophages were retained at the repaired site in the LR-PRP and LP-PRP groups. Enzyme-linked immunoassay results showed that the concentrations of IL-1β and TNF-α in the LR-PRP group were significantly higher than those in the other groups at 4 and 8 weeks, while the concentrations of IL-1β and TNF-α in the LP-PRP group were significantly lower than those in the control group. The biomechanical properties of the BTI were significantly improved in the PRP group. Significantly higher failure load and ultimate strength were seen in the LR-PRP and LP-PRP groups than in the control group at 4 and 8 weeks postoperatively. Thus, LR-RPR can effectively enhance the early stage of bone-tendon interface healing after rotator cuff repair, and LP-PRP could enhance the later stages of healing after rotator cuff injury.

Non-operative orthobiologic use for rotator cuff disorders and glenohumeral osteoarthritis: A systematic review

BACKGROUND

Shoulder pain from rotator cuff pathology and glenohumeral osteoarthritis is a common entity encountered in musculoskeletal practices. Orthobiologic agents are being increasingly used as a treatment option and understanding their safety and efficacy is necessary.

OBJECTIVE

To systematically evaluate the available evidence for orthobiologic use in rotator cuff and glenohumeral pathology.

METHODS

A systematic review was undertaken following PRISMA guidelines. Randomized clinical trials (RCTs) and prospective cohort studies evaluating non-operative treatment with prolotherapy, platelet-rich plasma (PRP), or medicinal signaling cells (MSCs) for rotator cuff pathology and glenohumeral osteoarthritis were included. Bias risk assessments used were the Cochrane tool and Newcastle-Ottawa score.

RESULTS

The search yielded 852 potential articles, of which 20 met the inclusion criteria with a breakdown of 5 prolotherapy, 13 PRP, and 2 MSC. Sixteen studies were RCTs and 4 were cohort studies. Six studies were deemed "low risk of bias or good quality". Efficacy results were mixed, and no serious adverse events were reported from orthobiologic treatment.

CONCLUSIONS

Orthobiologics offer a relatively safe management option with inconclusive evidence for or against its use for rotator cuff pathology. No studies on glenohumeral osteoarthritis met the inclusion criteria. Adoption of standardized preparation reporting and consistent use of functional outcome measures is imperative for future studies to consider.

Selected Clinical Features Fail to Predict Inflammatory Gene Expressions for TNF-α, TNFR1, NSMAF, Casp3 and IL-8 in Tendons of Patients with Rotator Cuff Tendinopathy

The pathophysiology of rotator cuff tendinopathy is not fully understood, particularly in terms of the local inflammatory process. This study aimed to investigate the expression of selected molecules in the tumour necrosis factor (TNF)-α transduction pathway, including TNF-α, TNF receptor 1 (TNFR1), neutral sphingomyelinase activation associated factor (NSMAF), caspase 3 (Casp3), and interleukin (IL)-8, in patients with rotator cuff tendinopathy that had undergone surgical treatment. We included 44 participants that underwent arthroscopy, due to rotator cuff tendinopathy. Samples from the injured tendon were collected during arthroscopy, and RT-PCR was performed to determine gene expression. Pearson correlation analyses or U-Mann–Whitney test were performed to identify associations with the following parameters: sex, age at admission, body mass index, the presence of night pain, previous treatment (nonsteroidal anti-inflammatory drugs and/or steroids), medical history of the shoulder injury, upper subluxation of the humeral head, and the number of tendons injured. RT-PCR showed that the selected pro-inflammatory factors involved in the TNF-α signalling pathway expression levels were expressed in the tendon tissues. However, the levels of expression varied from patient to patient. Variations were over 250-fold for TNF-α, about 130-fold for TNFR1, NSMAF, and Casp3, and 1000-fold for IL-8. We could not confirm that any of the clinical parameters investigated were associated with the level of gene expression in the TNF-α pathway and IL-8.

Efficacy of Adjuvant Application of Platelet-Rich Plasma After Needle Aspiration of Calcific Deposits for the Treatment of Rotator Cuff Calcific Tendinitis: A Double-Blinded, Randomized Controlled Trial With 2-Year Follow-up

BACKGROUND

Needle aspiration of calcific deposits (NACD) is a frequently used treatment for rotator cuff calcific tendinitis (RCCT). However, a substantial number of patients experience recurrent or persisting shoulder symptoms after NACD.

PURPOSE

To compare the effects of adjuvant application of platelet-rich plasma (PRP) after NACD (NACP+PRP) with those of conventional NACD with corticosteroids (NACD+corticosteroids) on pain, shoulder function, and quality of life (QoL).

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

In a single-center, double-blinded, randomized controlled trial, 80 adults with symptomatic RCCT were randomly allocated to receive NACD+corticosteroids or NACD+PRP. Pain, shoulder function, and QoL were assessed at baseline; 6 weeks; and 3, 6, 12, and 24 months after treatment using a numeric rating scale for pain (NRS); the Constant-Murley score (CMS); the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH); the Oxford Shoulder Score (OSS); and the EuroQol 5-dimension scale (EQ-5D). Additionally, resorption of calcific deposits and the integrity of rotator cuff tendons were assessed by using standard radiographs and ultrasound examination, respectively. The results were analyzed using noninferiority analysis for NRS scores and a mixed model for repeated measures.

RESULTS

Eighty patients were included (48 female; mean age, 49 ± 6 years; 41 patients in the NACD+PRP group). Both groups showed improvement of clinical scores at the 2-year follow-up (P < .001 for all clinical scores). NACD+PRP was found to be noninferior to NACD+corticosteroids with regard to the mean decrease of NRS scores (4.34 vs 3.56; P = .003). Mixed-model analysis showed a significant difference in favor of NACD+PRP (CMS, P < .001; DASH, P = .002; OSS, P = .010; EQ-5D, P < .001). However, clinically relevant differences in favor of NACD+PRP were only seen at the 6-month follow-up for NRS and CMS scores, whereas at the 6-week follow-up a clinically relevant difference in favor of NACD+corticosteroids was found for all clinical scores except for the NRS. Full resorption of calcific deposits was present in 84% of the NACD+PRP group compared with 66% in the NACD+corticosteroids group (P = .081). In the NACD+PRP group, 10 (24%) patients required a second NACD procedure compared with 19 (49%) patients in the NACD+corticosteroids group (P = .036). Six complications, of which 5 were frozen shoulders, occurred in the NACD+PRP group compared with 1 complication in the NACD+corticosteroids group (P = .11).

CONCLUSION

NACD+PRP resulted in worse clinical scores at the 6-week follow-up but better clinical scores at the 6-month follow-up compared with NACD+corticosteroids. At the 1- and 2-year follow-ups, the results were comparable between groups. Furthermore, PRP seemed to reduce the need for additional treatments but was associated with more complications. In conclusion, NACD+corticosteroids had a favorable early effect on pain and function combined with low comorbidity. Thus, it remains the treatment of choice for patients with RCCT.

REGISTRATION

NCT02173743 (ClinicalTrials.gov identifier).

Platelet-rich plasma injection vs corticosteroid injection for conservative treatment of rotator cuff lesions: A systematic review and meta-analysis

BACKGROUND

To explore the effectiveness of platelet-rich plasma (PRP) injection regarding functional recovery, pain relief, and range of motion (ROM) of shoulder compared with the corticosteroid injection in patients with rotator cuff lesions treated non-operatively.

METHODS

An electronic literature search was performed by 2 authors in the PubMed, Embase, Cochrane Library, and Web of Science databases to identify relevant randomized controlled trial (RCTs) that were published up to July 20, 2020. The quality of the included RCTs was evaluated using the approach recommended by the Cochrane Handbook for Systematic Reviews of Interventions. Standardized mean differences (SMDs) or mean differences (MDs) with 95% confidence intervals (CIs) were applied to calculate the pooled effect sizes.

RESULTS

Six RCTs were included in this systematic review. Meta-analysis revealed that corticosteroid injection yielded statistically significant superior functional recovery (SMD = -0.80; 95% CI, -1.42 to -0.18; P = .01) and pain relief (MD = 1.59; 95% CI, 0.30-2.89; P = .02) compared with PRP injection for rotator cuff lesions during the short-term follow-up period. However, at the medium-term and long-term follow-up, no statistically significant difference was identified between the 2 groups. Regarding the ROM of shoulder, no statistically significant difference was found between the 2 groups during the whole follow-up period.

CONCLUSIONS

The current clinical evidence revealed short-term efficacy of corticosteroid injection and no significant medium- to long-term difference between corticosteroid and PRP injection in the treatment of rotator cuff lesions. Additional studies with longer follow-ups, larger sample sizes, and more rigorous designs are needed to draw more reliable and accurate conclusions.

Platelet-rich plasma versus hyaluronic acid in the treatment of knee osteoarthritis: a meta-analysis

Background

This study aimed to evaluate the clinical efficacy of platelet-rich plasma (PRP) injection compared with hyaluronic acid (HA) injection for patients undergoing knee osteoarthritis.

Methods

We systematically searched electronic databases including PubMed, Embase, Web of Science, and the Cochrane Library on January 23, 2020 to identify relevant studies issued in English languages. The outcomes evaluating the efficacy of knee osteoarthritis (KOA) treatment were Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores (WOMAC pain, function, stiffness, and total scores) at 1, 3, 6, and 12 months; International Knee Documentation Committee (IKDC) scores, Lequesne Index score, Visual Analog Scale (VAS) scores, EQ-VAS scores, and KOOS scores. The pooled data were analyzed by Stata 12.0.

Results

A total of 20 RCTs were enrolled in the present meta-analysis. The pooled results demonstrated that platelet-rich plasma (PRP) injection reduced pain more effectively than hyaluronic acid (HA) injection at 6-month and 12-month follow-up evaluated by WOMAC pain scores and VAS scores. EQ-VAS in the patients treated with PRP injection was lower than that in patients with HA injection at 12 months. Moreover, the patients with PRP injection had a better function recovery than those with HA injection at 1-month, 3-month, 6-month, and 12-month follow-up, as evaluated by WOMAC function scores. WOMAC total scores showed significant difference at 6-month and 12-month follow-up. The IKDC scores indicated PRP injection was significantly more effective than HA injection at 3 months and 6 months. However, the Lequesne Index scores, KOOS scores, and adverse events did not show any significant difference between groups.

Conclusion

Intra-articular PRP injection appeared to be more efficacious than HA injection for the treatment of KOA in terms of short-term functional recovery. Moreover, PRP injection was superior to HA injection in terms of long-term pain relief and function improvement. In addition, PRP injection did not increase the risk of adverse events compared to HA injection.

Recovery of Tendon Characteristics by Inhibition of Aberrant Differentiation of Tendon-Derived Stem Cells from Degenerative Tendinopathy

The inhibition of the aberrant differentiation of tendon-derived stem cells (TDSCs) is a major target for the regeneration of damaged tendon tissues, as tendinopathy can be caused by the aberrant differentiation of TDSCs. We investigated whether the possible aberrant differentiation of TDSCs can be prevented by using adequate inhibitors. TDSCs extracted from chemically induced tendinopathy and injury-with-overuse tendinopathy models were cultured with 18α-glycyrrhetinic acid (AGA) and T0070907 to block osteogenic differentiation and adipogenic differentiation, respectively. The optimal dose of AGA decreased the osteogenic-specific marker Runx2 (Runt-related transcription factor 2), and T0070907 blocked the adipogenic-specific marker peroxisome proliferator-activated receptor gamma (PPARγ) in mRNA levels. We also found that AGA induced tenogenic differentiation in mRNA levels. However, T0070907 did not affect the tenogenic differentiation and regenerative capacity of TDSCs. We expect that optimal doses of AGA and T0070907 can prevent tendinopathy by inhibiting osteogenic and adipogenic differentiation, respectively. In addition, AGA and T0070907 may play important roles in the treatment of tendinopathy.