Objectives. After an injury, the biological reattachment of tendon to bone is a challenge because healing takes place between a soft (tendon) and a hard (bone) tissue. Even after healing, the transition zone in the enthesis is not completely regenerated, making it susceptible to re-injury. In this study, we aimed to regenerate Achilles tendon entheses (ATEs) in wounded rats using a combination of kartogenin (KGN) and platelet-rich plasma (PRP). Methods. Wounds created in rat ATEs were given three different treatments: kartogenin platelet-rich plasma (KGN-PRP); PRP; or saline (control), followed by histological and immunochemical analyses, and mechanical testing of the rat ATEs after three months of healing. Results. Histological analysis showed well organised arrangement of collagen fibres and proteoglycan formation in the wounded ATEs in the KGN-PRP group. Furthermore, immunohistochemical analysis revealed fibrocartilage formation in the KGN-PRP-treated ATEs, evidenced by the presence of both collagen I and II in the healed ATE. Larger positively stained collagen III areas were found in both PRP and saline groups than those in the KGN-PRP group. Chondrocyte-related genes, SOX9 and collagen II, and tenocyte-related genes, collagen I and scleraxis (SCX), were also upregulated by KGN-PRP. Moreover, mechanical testing results showed higher ultimate tensile strength in the KGN-PRP group than in the saline control group. In contrast, PRP treatment appeared to have healed the injured ATE but induced no apparent formation of fibrocartilage. The saline-treated group showed poor healing without fibrocartilage tissue formation in the ATEs. Conclusions. Our results show that injection of KGN-PRP induces fibrocartilage formation in the wounded rat ATEs. Hence, KGN-PRP may be a clinically relevant, biological approach to regenerate injured enthesis effectively. Cite this article: J. Zhang, T. Yuan, N. Zheng, Y. Zhou, M. V. Hogan, J. H-C. Wang. The combined use of kartogenin and platelet-rich plasma promotes fibrocartilage formation in the wounded rat Achilles tendon entheses. Bone Joint Res 2017;6:231–244. DOI: 10.1302/2046-3758.64.BJR-2017-0268.R1

Objectives. This study was conducted to evaluate the cytokine-release kinetics of platelet-rich plasma (PRP) according to different activation protocols. Methods. Two manual preparation procedures (single-spin (SS) at 900 g for five minutes; double-spin (DS) at 900 g for five minutes and then 1500 g for 15 minutes) were performed for each of 14 healthy subjects. Both preparations were tested for platelet activation by one of three activation protocols: no activation, activation with calcium (Ca) only, or calcium with a low dose (50 IU per 1 ml PRP) of thrombin. Each preparation was divided into four aliquots and incubated for one hour, 24 hours, 72 hours, and seven days. The cytokine-release kinetics were evaluated by assessing PDGF, TGF, VEGF, FGF, IL-1, and MMP-9 concentrations with bead-based sandwich immunoassay. Results. The concentration of cytokine released from PRP varied over time and was influenced by various activation protocols. Ca-only activation had a significant effect on the DS PRPs (where the VEGF, FGF, and IL-1 concentrations were sustained) while Ca/thrombin activation had effects on both SS and DS PRPs (where the PDGF and VEGF concentrations were sustained and the TGF and FGF concentrations were short). The IL-1 content showed a significant increase with Ca-only or Ca/thrombin activation while these activations did not increase the MMP-9 concentration. Conclusion. The SS and DS methods differed in their effect on cytokine release, and this effect varied among the cytokines analysed. In addition, low dose of thrombin/calcium activation increased the overall cytokine release of the PRP preparations over seven days, relative to that with a calcium-only supplement or non-activation. Cite this article: Professor J. H. Oh. Cytokine-release kinetics of platelet-rich plasma according to various activation protocols. Bone Joint Res 2016;5:37–45. doi: 10.1302/2046-3758.52.2000540

The use of stem cells transplanted into the intervertebral disc (IVD) is a promising regenerative approach to treat intervertebral disc degeneration (IDD). The aim of this study was to assess the effect of a hydrogel composed of hyaluronic acid (HA) and platelet-rich plasma (PRP) loaded with human mesenchymal stem cells (hMSCs), on IVD extracellular matrix synthesis and nucleus pulposus (NP) marker expression in a whole IVD culture model. HA was blended with batroxobin (BTX), a gelling agent activated in presence of PRP to construct a hydrogel. Bovine IVDs (n=25) were nucleotomised and filled with 1×10. 6. or 2×10. 6. hMSCs suspended in ∼150 mL of the PRP/HA/BTX hydrogel. IVDs harvested at day 0 and nucleotomised IVDs with no hMSCs and/or hydrogel were used as controls. hMSCs alone or encapsulated in the hydrogel were also cultured in well plates to examine the effect of the IVD microenvironment on hMSCs. After 1 week, tissue structure, scaffold integration and gene expression of anabolic (collagen type I, collagen type II and aggrecan), catabolic (matrix metalloproteinase 3 – MMP-3 –, MMP-13 and a disintegrin and metalloproteinase with thrombospondin motifs 4) and NP cell (cytokeratin 19, carbonic anhydrase 12, cluster of differentiation 24) markers were assessed. Histological analysis showed a good integration of the scaffold within the NP area with cell repopulation. At the gene expression level, the hMSC-loaded hydrogels demonstrated to increase disc cell anabolic and catabolic marker expression and promoted hMSC differentiation towards a NP cell phenotype. This study demonstrated that the HA/PRP/BTX may represent a valid carrier for hMSCs being capable of stimulating cell activity and NP marker expression as well as achieving a good integration with the surrounding tissues

The aim of our study was to investigate the effect of platelet-rich plasma on the proliferation and differentiation of rat bone-marrow cells and to determine an optimal platelet concentration in plasma for osseous tissue engineering. Rat bone-marrow cells embedded in different concentrations of platelet-rich plasma gel were cultured for six days. Their potential for proliferation and osteogenic differentiation was analysed. Using a rat limb-lengthening model, the cultured rat bone-marrow cells with platelet-rich plasma of variable concentrations were transplanted into the distraction gap and the quality of the regenerate bone was evaluated radiologically. Cellular proliferation was enhanced in all the platelet-rich plasma groups in a dose-dependent manner. Although no significant differences in the production and mRNA expression of alkaline phosphatase were detected among these groups, mature bone regenerates were more prevalent in the group with the highest concentration of platelets. Our results indicate that a high platelet concentration in the platelet-rich plasma in combination with osteoblastic cells could accelerate the formation of new bone during limb-lengthening procedures

There is good scientific rationale to support the use of growth factors to promote musculoskeletal tissue regeneration. However, the clinical effectiveness of platelet-rich plasma (PRP) and other blood-derived products has yet to be proven. Characterization and reporting of PRP preparation protocols utilized in clinical trials for the treatment of musculoskeletal disease is highly inconsistent, and the majority of studies do not provide sufficient information to allow the protocols to be reproduced. Furthermore, the reporting of blood-derived products in orthopaedics is limited by the multiple PRP classification systems available, which makes comparison of results between studies challenging. Several attempts have been made to characterize and classify PRP; however, no consensus has been reached, and there is lack of a comprehensive and validated classification. In this annotation, we outline existing systems used to classify preparations of PRP, highlighting their advantages and limitations. There remains a need for standardized universal nomenclature to describe biological therapies, as well as a comprehensive and reproducible classification system for autologous blood-derived products. Cite this article: Bone Joint J 2019;101-B:891–896

Aims. The present study investigates the effectiveness of platelet-rich plasma (PRP) gel without adjunct to induce cartilage regeneration in large osteochondral defects in a rabbit model. Methods. A bilateral osteochondral defect was created in the femoral trochlear groove of 14 New Zealand white rabbits. The right knees were filled with PRP gel and the contralateral knees remained untreated and served as control sides. Some animals were killed at week 3 and others at week 12 postoperatively. The joints were harvested and assessed by Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) MRI scoring system, and examined using the International Cartilage Repair Society (ICRS) macroscopic and ICRS histological scoring systems. Additionally, the collagen type II content was evaluated by the immunohistochemical staining. Results. After 12 weeks post-surgery, the defects of the PRP group were repaired by hyaline cartilage-like tissue. However, incomplete cartilage regeneration was observed in the PRP group for three weeks. The control groups showed fibrocartilaginous or fibrous tissue, respectively, at each timepoint. Conclusion. Our study proved that the use of PRP gel without any adjuncts could successfully produce a good healing response and resurface the osteochondral defect with a better quality of cartilage in a rabbit model. Cite this article: Bone Joint Res 2021;10(3):192–202

Aims. Bone marrow-derived mesenchymal stem cells obtained from bone marrow aspirate concentrate (BMAC) with platelet-rich plasma (PRP), has been used as an adjuvant to hip decompression. Early results have shown promise for hip preservation in patients with osteonecrosis (ON) of the femoral head. The purpose of the current study is to examine the mid-term outcome of this treatment in patients with precollapse corticosteroid-induced ON of the femoral head. Methods. In all, 22 patients (35 hips; 11 males and 11 females) with precollapse corticosteroid-induced ON of the femoral head underwent hip decompression combined with BMAC and PRP. Mean age and BMI were 43 years (SD 12) and 31 kg/m² (SD 6), respectively, at the time of surgery. Survivorship free from femoral head collapse and total hip arthroplasty (THA) and risk factors for progression were evaluated at minimum five-years of clinical follow-up with a mean follow-up of seven years (5 to 8). Results. Survivorship free from femoral head collapse and THA for any reason was 84% and 67% at seven years postoperatively, respectively. Risk factors for conversion to THA included a high preoperative modified Kerboul angle (grade 3 or 4) based on preoperative MRI (hazard ratio (HR) 3.96; p = 0.047) and corticosteroid use at the time of decompression (HR 4.15; p = 0.039). The seven-year survivorship for patients with grade 1 or 2 Kerboul angles for conversion to THA for articular collapse, and THA for any reason, were 96% and 72%, respectively, versus THA for articular collapse and THA for any reason in patients with grade 3 or 4 Kerboul angles of 40% (p = 0.003) and 40% (p = 0.032). Conclusion. At seven years, hip decompression augmented with BMAC and PRP provided a 67% survivorship free from THA in patients with corticosteroid-induced ON. Ideal candidates for this procedure are patients with low preoperative Kerboul angles and can stop corticosteroid treatment prior to decompression. Cite this article: Bone Jt Open 2021;2(11):926–931

Platelet-rich plasma (PRP) has been demonstrated to benefit a variety of disciplines. But there exists heterogeneity in results obtained due to lack of standardization of the preparation protocols employed in them. We aim to identify and standardize a preparation protocol for PRP with maximum recovery of platelets to obtain reproducible results across studies. Blood samples were collected from 20 healthy volunteers. The double spin protocol of PRP preparation was analyzed for variables such as centrifugal acceleration, time, and volume of blood processed and final product utilized. The final PRP prepared was investigated for platelet recovery, concentration, integrity, and viability. We noted maximum platelet recovery (86-99%) with a mean concentration factor of 6-times baseline, with double centrifugation protocol at 100xg and 1600xg for 20 minutes each. We also noted that 10 ml of blood in a 15 ml tube was the ideal volume of blood to be processed to maximize platelet recovery. We demonstrated that the lower 1/3rd is the ideal volume to be utilized for clinical application. We did not note a loss of integrity or viability of the platelets in the final product from the above-said protocol. Preparation of PRP by the double spin protocol of 10 ml of blood at 100xg and 1600xg for 20 minutes each in a 15ml tube and using the lower 1/3rd of the final product demonstrated consistent high platelet recovery (86-99%) and concentration (6x) without disturbing the platelet integrity or viability

Objectives. Triamcinolone acetonide (TA) is widely used for the treatment of rotator cuff injury because of its anti-inflammatory properties. However, TA can also produce deleterious effects such as tendon degeneration or rupture. These harmful effects could be prevented by the addition of platelet-rich plasma (PRP), however, the anti-inflammatory and anti-degenerative effects of the combined use of TA and PRP have not yet been made clear. The objective of this study was to determine how the combination of TA and PRP might influence the inflammation and degeneration of the rotator cuff by examining rotator cuff-derived cells induced by interleukin (IL)-1ß. Methods. Rotator cuff-derived cells were seeded under inflammatory stimulation conditions (with serum-free medium with 1 ng/ml IL-1ß for three hours), and then cultured in different media: serum-free (control group), serum-free + TA (0.1mg/ml) (TA group), serum-free + 10% PRP (PRP group), and serum-free + TA (0.1mg/ml) + 10% PRP (TA+PRP group). Cell morphology, cell viability, and expression of inflammatory and degenerative mediators were assessed. Results. Exposure to TA significantly decreased cell viability and changed the cell morphology; these effects were prevented by the simultaneous administration of PRP. Compared with the control group, expression levels of inflammatory genes and reactive oxygen species production were reduced in the TA, PRP, and TA+PRP groups. PRP significantly decreased the expression levels of degenerative marker genes. Conclusions. The combination of TA plus PRP exerts anti-inflammatory and anti-degenerative effects on rotator cuff-derived cells stimulated by IL-1ß. This combination has the potential to relieve the symptoms of rotator cuff injury. Cite this article: T. Muto, T. Kokubu, Y. Mifune, A. Inui, R. Sakata, Y. Harada, F. Takase, M. Kurosaka. Effects of platelet-rich plasma and triamcinolone acetonide on interleukin-1ß-stimulated human rotator cuff-derived cells. Bone Joint Res 2016;5:602–609. DOI: 10.1302/2046-3758.512.2000582

Aims. Platelet-rich plasma (PRP) intra-articular injections may provide a simple and minimally invasive treatment for early-stage knee osteoarthritis (OA). This has led to an increase in its adoption as a treatment for knee OA, although there is uncertainty about its efficacy and benefit. We hypothesized that patients with early-stage symptomatic knee OA who receive multiple PRP injections will have better clinical outcomes than those receiving single PRP or placebo injections. Methods. A double-blinded, randomized placebo-controlled trial was performed with three groups receiving either placebo injections (Normal Saline), one PRP injection followed by two placebo injections, or three PRP injections. Each injection was given one week apart. Outcomes were prospectively collected prior to intervention and then at six weeks, three months, six months, and 12 months post-intervention. Primary outcome measures were Knee Injury and Osteoarthritis Outcome Score (KOOS) and EuroQol five-dimension five-level index (EQ-5D-5L). Secondary outcomes included visual analogue scale for pain and patient subjective assessment of the injections. Results. A total of 102 patients were recruited. The follow-up period was 12 months, at intervals of six weeks, 12 weeks, six months, and 12 months. KOOS-Total significantly improved in all groups at these time intervals compared to pre-injection. There was an improvement in EQ-5D-5L index scores in saline and single injection groups, but not in the multiple injection group. Comparison of treatment groups showed no additional beneficial effect of single or multiple PRP injections above that displayed in the saline injection group. Subjective patient satisfaction and recommendation of treatment received demonstrated a similar pattern in all the groups. There was no indication of superiority of either single or multiple PRP injections compared to saline injections. Conclusion. There is no evidence that single or multiple PRP had any additional beneficial effect compared to saline injection up to 12 months, follow-up after treatment of early stage symptomatic OA of the knee. Cite this article: Bone Joint J 2022;104-B(6):663–671

There are a number of patients in whom hip preservation surgery is not indicated as they have developed signs of early osteoarthritis, and nor can they have a hip replacement as they are too early in the disease process. The use of PRP in OA of the hip has not been studied systematically and this study concisely collates all the available data in the use of PRP in Hip OA. This systematic review and meta-analysis aimed to assess intra-articular platelet-rich plasma as a therapeutic intervention for hip osteoarthritis, including the duration of efficacy, influence of dose and composition of PRP, and the incidence of adverse effects. We performed literature searches on the MEDLINE, EMBASE, CINHAL, WEB OF SCIENCE, COCHRANE and SCOPUS databases, and PRSIMA guidelines were followed. Data was pooled using random effects meta-analysis. We assessed quality of the included studies using the Methodological Index for Non-Randomised Studies (MINORS) instrument, with an additional assessment for Randomised Controlled Trials with the Revised Cochrane risk-of-bias tool for randomized trials (RoB 2). Eight studies were included in the analysis, with data from a total of 331 patients. PRP significantly reduced pain compared to baseline at multiple timepoints, with the greatest effect at 1–2mo follow-up. PRP only significantly improved function at the 1–2mo follow-up. A significantly larger reduction in pain was achieved with a single injection or PRP compared to multiple injections, a total injected dose of PRP <15mL compared to ≥15mL or using a leukocyte-poor PRP preparation compared to leukocyte-rich PRP. There were no lasting adverse effects. Low and moderate quality evidence suggests that PRP reduces pain and improves function at endpoint compared to baseline. Moderate quality evidence suggests a larger reduction in pain is achieved with a single injection of PRP compared to multiple injections, and low quality evidence attributes a larger reduction of pain with a total injected dose of PRP <15mL compared to ≥15mL or using leukocyte-poor PRP compared to leukocyte-rich PRP

We performed this systematic overview on the overlapping meta-analyses that analyzed autologous platelet-rich plasma (PRP) as an adjuvant in the repair of rotator cuff tears and identify the studies which provide the current best evidence on this subject and generate recommendations for the same. We conducted independent and duplicate electronic database searches in PubMed, Web of Science, Scopus, Embase, Cochrane Database of Systematic Reviews, and the Database of Abstracts of Reviews of Effects on September 8, 2021, to identify meta-analyses that analyzed the efficacy of PRP as an adjuvant in the repair of rotator cuff tears. Methodological quality assessment was made using Oxford Levels of Evidence, AMSTAR scoring, and AMSTAR 2 grades and used the Jadad decision algorithm to generate recommendations. 20 meta-analyses fulfilling the eligibility criteria were included. The AMSTAR scores of the included studies varied from 6–10 (mean:7.9). All the included studies had critically low reliability in their summary of results due to their methodological flaws according to AMSTAR 2 grades. The initial size of the tear and type of repair performed do not seem to affect the benefit of PRPs. Among the different preparations used, leucocyte poor (LP)-PRP possibly offers the greatest benefit as a biological augment in these situations. Based on this systematic overview, we give a Level II recommendation that intra-operative use of PRPs at the bone-tendon interface can augment the healing rate, reduce re-tears, enhance the functional outcomes and mitigate pain in patients undergoing arthroscopic rotator cuff repair

Introduction. Rotator cuff healing after an arthroscopic repair is discussible because of the high incidence of failures. Among biologic augmentations currently used, platelet-rich plasma (PRP) is one of the most applied, supposed to enhance and accelerate the healing process in different musculoskeletal disorders. However, the evidence supporting its successful administration is still lacking, especially in the field of the rotator cuff repair. Our purpose is to clarify if the recovery is accelerated and the integrity of repaired construct is increased in patients undergoing PRP injections after arthroscopic repair of the rotator cuff. Patients & Methods. Thirty-eight patients with full-thickness rotator cuff tears have been enrolled after they had been informed about the use of PRP and the timing of its application postoperatively. Seventeen patients underwent arthroscopic rotator cuff repair and PRP injections (3 injections at 10 days each other), 21 underwent arthroscopic rotator cuff repair without PRP injections. Outcomes were assessed preoperatively, at 3, 6, 12, and minimum 16 months after surgery (average 17.7 +/− 1.7 months). Constant system, the University of California at Los Angeles (UCLA) system and a Visual Analogue Scale (VAS) scale were used; range of motion and strength in all planes were also assessed. The healing of the repair was assessed at magnetic resonance imaging at a minimum follow up of 6 months from surgery. All patients had the same rehabilitation protocol. Results. Platelet-rich plasma gel application after to arthroscopic rotator cuff tear repairs did not accelerate recovery with respect to pain, range of motion, strength, functional scores, or overall satisfaction as compared with conventional repair at any time point. There was no difference between the 2 groups after 3, 6, 12, months and at final follow up. The follow-up MRI showed no significant difference in the healing rate of the rotator cuff tear. In addition, magnetic resonance imaging, at a minimum of 6 months after surgery, demonstrated a retear rate of 23.5 % in the PRP group and 19% in the conventional group, there was no statistical significance between the groups (P = .658). Discussion/Conclusion. Although PRP application after arthroscopic repair of the rotator cuff has no effects on clinical recovery and structural integrity, it reduces the postoperative occurrence of shoulder stiffness. Further studies should support these findings

Surgical reattachment of torn rotator cuff tendons can lead to satisfactory clinical outcome but failures remain common. Ortho-R product is a freeze-dried formulation of chitosan (CS) that is solubilized in platelet-rich plasma (PRP) to form injectable implants. The purpose of the current pilot study was to determine Ortho-R implant acute residency, test safety of different implant doses, and assess efficacy over standard of care in a sheep model. The infraspinatus tendon (ISP) was detached and immediately repaired in 22 skeletally mature ewes. Repair was done with four suture anchors in a suture bridge configuration (n = 6 controls). Freeze-dried formulations containing 1% w/v chitosan (number average molar mass 35 kDa and degree of deacetylation 83%) with 1% w/v trehalose (as lyoprotectant) and 42.2 mM calcium chloride (as clot activator) were solubilized with autologous leukocyte-rich PRP and injected at the tendon-bone interface and on top of the repaired site (n = 6 with a 1 mL dose and n = 6 with a 2 mL dose). Acute implant residency was assessed histologically at 1 day (n = 2 with a 1 mL dose and n = 2 with a 2 mL dose). Outcome measures included MRI assessment at baseline, 6 weeks and 12 weeks, histopathology at 12 weeks and clinical pathology. MRI images and histological slides were scored by 2 blinded readers (veterinarian and human radiologist, and veterinarian pathologist) and averaged. The Generalized Linear Model task (SAS Enterprise Guide 7.1 and SAS 9.4) was used to compare the different groups with post-hoc analysis to test for pairwise differences. Ortho-R implants were detected near the enthesis, near the top of the anchors holes and at the surface of ISP tendon and muscle at 1 day. Numerous polymorphonuclear cells were recruited to the implant in the case of ISP tendon and muscle. On MRI, all repair sites were hyperintense compared to normal tendon at 6 weeks and only 1 out 18 repair sites was isointense at 12 weeks. The tendon repair site gap seen on MRI, which is the length of the hyperintense region between the greater tuberosity and tendon with normal signal intensity, was decreased by treatment with the 2 mL dose when compared to control at 12 weeks (p = 0.01). Histologically, none of the repair sites were structurally normal. A trend of improved structural organization of the tendon (p = 0.06) and improved structural appearance of the enthesis (p = 0.1) with 2 mL dose treatment compared to control was seen at 12 weeks. There was no treatment-specific effect on all standard safety outcome measures, which suggests high safety. Ortho-R implants (2 mL dose) modulated the rotator cuff healing processes in this large animal model. The promising MRI and histological findings may translate into improved mechanical performance, which will be assessed in a future study with a larger number of animals. This study provides preliminary evidence on the safety and efficacy of Ortho-R implants in a large animal model that could potentially be translated to a clinical setting

Although mechanical stabilisation has been a hallmark of orthopaedic surgical management, orthobiologics are now playing an increasing role. Platelet-rich plasma (PRP) is a volume of plasma fraction of autologous blood having platelet concentrations above baseline. The platelet α granules are rich in growth factors that play an essential role in tissue healing, such as transforming growth factor-β, vascular endothelial growth factor, and platelet-derived growth factor. PRP is used in various surgical fields to enhance bone and soft-tissue healing by placing supraphysiological concentrations of autologous platelets at the site of tissue damage. The easily obtainable PRP and its possible beneficial outcome hold promise for new regenerative treatment approaches. The aim of this literature review was to describe the bioactivities of PRP, to elucidate the different techniques for PRP preparation, to review animal and human studies, to evaluate the evidence regarding the use of PRP in trauma and orthopaedic surgery, to clarify risks, and to provide guidance for future research

OBJECTIVE: The purpose of this study is to examine the effect of a single percutaneous injection of platelet-rich-plasma compared to an injection of corticosteroids in patients with chronic lateral epicondylitis. BACKGROUND: Lateral epicondylitis is a common problem that usually resolves with nonoperative treatments. Platelet Rich Plasma (PRP) is a component of whole blood that contains concentrated amounts of powerful growth factors. PRP has been used for a variety of orthopedic applications including tendinopathy, wound healing and spinal fusion with varying degrees of success. Buffered PRP has also been used to enhance cell proliferation in-vitro. HYPOTHESIS: Treatment of chronic severe lateral epicondylitis with buffered platelet-rich plasma will reduce pain and increase function in patients considering surgery for their problem. METHODS: One hundred patients with persistent lateral epicondylar pain were evaluated in this study. All these patients were initially given a variety of nonoperative treatments. These patients had significant persistent pain for at least 3 months despite these interventions. All patients were considering surgery. This cohort of patients who had failed nonoperative treatment was then given either a single percutaneous injection of platelet-rich plasma (experimental group, n = 50) or corticosteroids (control group, n = 50). RESULTS: PRP has a significant better effect on lateral epicondylitis than corticosteroid injections. CONCLUSION: This in-vivo data suggest that tendon healing is occurring in lateral epicondylitis using PRP

Introduction. The use of stem cell and platelet-rich plasma (PRP) injections for knee osteoarthritis (OA) is extremely controversial and at best experimental. These treatments are being given to patients across the nation for “cash only payments”. Our objectives were (1) to determine the proportion of board certified orthopedic surgeons who offer stem cell or PRP treatment for knee OA, (2) how much the practices charge for those treatments and (3) if members of the knee society use these therapies. Methods. Board certified orthopedic surgeons’ offices in our county were identified by their AAOS active membership. Knee society membership roll was also utilized. Offices were contacted by telephone and presented with a hypothetical patient with end stage knee osteoarthritis searching for specific treatment (stem cells or PRP injections). T-test was used to compare the Dade county board certified orthopedists to knee society members. Results. A total of 186 board certified orthopedic surgeons’ offices were contacted. 17.6% of all contacted orthopedics offices offered PRP and 12.5% offered stem cell treatments. 61.2% of the offices were transparent on the pricing of PRP while 31.8% gave a price for stem cell therapy. The remaining practices stated that pricing would be “determined or discussed” during a scheduled visit. Mean cost for a PRP injection was $887 (SE 101; range: $350–$1700) and for a stem cell injection was $2800 (SE 852; range: $1000–$6000). Usage of these therapies amongst general AAOS members and Knee Society members was found to be significantly different for both PRP and stem cells (17% vs. 10%; p<0.001 and 26% vs. 13%; p<0.001, respectively). No practice had a “free” research protocol to study the treatments. Conclusions. Biological injectables as a treatment for knee OA has theoretical potential promise in the management of arthritis but continues to be at best investigational. Knee Society members demonstrated significantly more caution using these treatments

Intra-articular injections of human mesenchymal stromal cells (MSCs) and platelet-rich plasma (PRP) have been intensively investigated as therapies for knee osteoarthritis (OA) with positive outcomes. In this work we evaluated weather a combination of the treatments (MSCs + PRP) would be beneficial compared to MSCs alone (MSCs) and standard corticosteroid injection (Control group). Forty seven patients (24 males and 23 females; 53.3 ± 10.7 years old) with radiographic symptomatic knee OA (Dejour grades II–IV) were randomized to receive intra-articular injections of MSCs (n = 16), MSCs + PRP (n = 14) or corticosteroid (n=17). MSCs were obtained after mononuclear cells separation from bone marrow aspiration collected from both posterior iliac crests using Sepax automated closed system and expanded in culture until reaching the number of 4 × 10. 7. PRP was obtained by double-centrifugation of whole blood according to a protocol developed in house. After 12 months follow-up, the MSCs and MSCs+PRP groups achieved higher percentages of expected improvement when comparing to the corticosteroid group for the KOOS-symptoms, pain, function and daily living, domains and global score. For the population older or equal to 60 years old the MSCs+PRP group showed significant superiority for the KOOS-ADL domain at 12 months. Cytokines quantification evidenced anti-inflammatory aspects of the treatments. This work evidences the safety and efficacy of intra-articular injection of MSCs for the treatment of early knee OA, with greater improvement with PRP addition particularly to the older population

The objective of this study was to evaluate the safety and the effect of platelet-rich plasma (PRP) intra-articular injections obtained from blood donors (homologous PRP) on elderly patients with early or moderate knee osteoarthritis (OA) who are not candidates for autologous PRP treatment. A total of 60 symptomatic patients, aged 65–86 years, affected by hematologic disorders and early or moderate knee OA, were treated with 5 ml of homologous PRP intraarticular injections every 14 days for a total of three injections. Clinical evaluations before the treatment, and after 2 and 6 months were performed by International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS) and Equal Visual Analogue Scale (EQ VAS) scores. Adverse events and patient satisfaction were recorded. No severe complications were noted during the treatment and the follow-up period. A statistically significant improvement from basal evaluation to the 2-month follow-up visit was observed, whereas a statistically significant worsening from the 2-month to the 6-month follow-up visit was showed. The overall worst results were observed in patients aged 80 years or over and in those affected by minor bone attrition. It was found that 90% of patients were satisfied at the 6-month evaluation. Homologous PRP has an excellent safety profile but offers only a short-term clinical improvement in selected elderly patients with knee OA who are not candidates for autologous PRP treatment. Increasing age and developing degeneration result in a decreased potential for homologous PRP injection therapy. Further studies are needed to confirm these findings

Greater trochanteric pain syndrome is a painful condition characterised by pain around the greater trochanter usually affecting middle-aged women. The majority of patients will improve with conservative management such as physiotherapy and non-steroidal anti-inflammatory drugs (NSAIDs); however, if this fails then more invasive treatments including corticosteroids and surgery may be required. Platelet-rich plasma (PRP) is an autologous blood product, which has a higher concentration of growth factors postulated to provide enhanced healing and anti-inflammatory properties. The Hip Injections PRP Vs Placebo (HIPPO) trial aims to assess the ability of ultrasound-guided PRP injections to improve symptoms and function in patients with GTPS. 64 patients were enrolled and randomised to either the PRP or placebo (normal saline) treatment arm. Two patients decided to drop out of the trial. Clinical outcomes in both groups were evaluated and compared using the International Hip Outcome Tool-12 (iHOT12), Visual Analogue Scale (VAS) of pain, the modified Harris Hip Score (mHHS) and the presence or absence of complications at 3 and six months. The level of significance was set at p<0.05. Both groups received physiotherapy after the injections. The mean age was 57.5. There were 6 males and 56 females with M:F ratio of 1:9.3. Both groups were similar in terms of demography and preoperative scores. The iHOT12 score improved from 28.23 to 45.42 at three-months and decreased slightly to 42.44 at six-months in the Placebo group. The iHOT12 in the PRP group improved from 35.51 to 44.47 at three-months and decreased to 39.78 at six-months. Both groups showed improved VAS and mHHS at three-months compared to the baseline with no statistically significant difference between the two groups (p >0.05). The scores decreased at six-months however remained above the baseline. No complications were reported. Gender and age had no effect on outcomes. Both groups similarly improved from baseline. Physiotherapy can be considered as an important factor in patients' treatment. Further research should be conducted to investigate the role of physiotherapy in the treatment of GTPS

The use of platelet-rich plasma (PRP) as an adjuvant to tissue repair is gaining favour in orthopaedic surgery. Tunnel widening after anterior cruciate ligament (ACL) reconstruction is a recognised phenomenon that could compromise revision surgery. The purpose of this study was to determine whether PRP might prevent tunnel widening in ACL reconstruction. Patients undergoing ACL reconstruction using a hamstring graft were randomly allocated either to have PRP introduced into the tunnels peri-operatively or not. CT scanning of the knees was carried out on the day after surgery and at three months post-operatively and the width of the tunnels was measured. Patients were also evaluated clinically at three months, when laxity was also measured. Each group comprised 25 patients, and at three months post-operatively all were pain-free with stable knees, a negative Lachman test and a good range of movement. Arthrometric results had improved significantly in both groups (p < 0.001). Despite slightly less tunnel widening in the PRP group, there was no significant difference between the groups at the femoral opening or the mid-tunnel (p = 0.370 and p = 0.363, respectively) nor at the tibial opening or mid-tunnel (p = 0.333 and p = 0.177, respectively). We conclude that PRP has no significant effect in preventing tunnel widening after ACL reconstruction. Cite this article: Bone Joint J 2013;95-B:65–9

Introduction. Interest in platelet-derived growth factors has been increasing as an adjunct in surgical techniques for tissue repair. Its use in ligament injuries repair has been studied mainly in animals. The authors intend to study growth factors influence in ACL repair using BTB graft. Material. 20 individuals underwent ACL rupture BTB arthroscopic repair, using Double Incision Mini-Invasive Technique. MRI (3-Tesla) images. GPSIII ® System to obtain Platelet-Rich Plasma (PRP) thrombin activated. Methods. Prospective study consisting of 2 groups of 10 patients each. Surgical technique, fixation method and postoperative protocol were the same. In the study group (SG-10 patients) graft was imbued with PRP and the remaing plasma was intra-articularly injected. The MRIs took place 6 weeks and 6 months after the procedure with and without gadolinium-DTPA enhancement. Evaluation was performed blindly by independent radiologists concerning femoral tunnel integration, sinovialization process and nonspecific synovitis. Clinical and functional status evaluation: IKDC. Statistical analysis in SPSS®. Results. Radiological evaluation was similar in both groups. In the Study Group at 6 weeks we verified less joint effusion and synovitis. At 6 months: no diference in integration in femoral tunnel, and in granulation tissue around the femoral tunnel in graft sinovialization. IKDC (mean ± SD) with PRP: pre-operative −45,66 ±6,98, post-operative −94,35 ±3,54 (Age-29 ± 10), without PRP: preoperative −48,02 ±12,68, post-operative −91,7 ±6,99 (Age −31 ±10). There are no statistical differences between the groups with and without PRP in clinical and functional assessments and MRI images. Discussion. The use of technology to accelerate and improve the processes of tissue repair and integration is of great interest in repairing the ACL. Studies in humans are rare, with low level of evidence and contradictory results. Although the limitations of this study, it seems to us that the use of growth factors has no advantages in the process of PT graft integration at 6 months. Conclusion. PRP doesn't seem to contribute to enhancement of the ligamentation process and articular rehabilitation when used as a step of BTB technique

Osteoarthritis (OA) is a debilitating disease characterised by degradation of articular cartilage and subchondral bone remodeling. Current therapies for early or midstage disease do not regenerate articular cartilage, or fail to integrate the repair tissue with host tissue, and therefore there is great interest in developing biological approaches to cartilage repair. We have shown previously that platelet-rich plasma (PRP) can enhance cartilage tissue formation. PRP is obtained from a patient's own blood, and is an autologous source of many growth factors and other molecules which may aid in healing. This raised the question as to whether PRP could enhance cartilage integration. We hypothesise that PRP will enhance integration of bioengineered cartilage with native cartilage. Chondrocytes were isolated from bovine metacarpal-phalangeal joints, seeded on a porous bone substitute (calcium polyphosphate) and grown in the presence of FBS to form an in vitro model of osteochondral-like tissue. After 7 days, the biphasic constructs were soaked in PRP for 30 minutes prior to implantation into the core of a ring-shaped biphasic explant of native bovine cartilage and bone. Controls were not soaked in PRP. The resulting implant-explant construct was cultured in a stirring bioreactor in serum free conditions for 2 weeks. The integration zone was visualised histologically. A push-out test was performed to assess the strength of integration. Matrix accumulation at the zone of integration was assessed biochemically and the gene expression of the cells in this region was assessed by RT-PCR. Significance (p<0.05) was assessed by a student's t-test or one-way ANOVA with tukey's post hoc. PRP soaked bioengineered implants, integrated with the host tissue in 73% of samples, whereas control bioengineered implants only integrated in 19% of samples based on macroscopic evaluation (p<0.05). The integration strength, as determined by the normalised maximum force to failure, was significantly increased in the PRP soaked implant group compared to controls (219 +/− 35.4 kPa and 72.0 +/− 28.5 kPa, respectively, p<0.05). This correlated with an increase in glycosaminoglycan and collagen accumulation in the region of integration in the PRP treated implant group, compared to untreated controls after 2 weeks (p<0.05). Immunohistochemical studies revealed that the integration zone was rich in collagen type II and aggrecan. The cells at the zone of integration in the PRP soaked group had a 2.5 fold increase in aggrecan gene expression (p=0.05) and a 3.5 fold increase in matrix metalloproteinase 13 expression (p<0.05) compared to controls. PRP soaked bio-engineered cartilage implants showed improved integration with native cartilage compared to non-treated implants, perhaps due to the increased matrix accumulation and remodeling at the interface. Further evaluation is required to determine if PRP improves integration in vivo

Platelet Rich Plasma (PRP), either rich (L-PRP) or poor (P-PRP) of leukocytes, is frequently used as an anti-inflammatory and regenerative tool in osteoarthritis (OA). PRP contains proteins but not genes as it is derived from megakaryocytes. Proteomics but not metabolomics of PRP was recently studied. Metabolomics is a field of ‘omics’ research involved in comprehensive portrayal of the small molecules, metabolites, in the metabolome. These small molecules can be endogenous metabolites or exogenous compounds found in an organism (1). Our aim was to determine the difference between L-PRP and P-PRP.

A cross-sectional clinical study was designed in six recreational male athletes between the ages of 18 and 35 years. 3 mL P-PRP and 3 mL -LPRP was prepared from 60 mL of venous blood after treating with 9 mL of sodium citrate and centrifugation at 2.700 rpm for 10 min. Half of the prepared PRP's were frozen at −20°C for a week. Fresh and frozen samples were analyzed at the Q-TOF LC/MS device after thawing to room temperature.

Untargeted metabolomic results revealed that the metabolomic profile of the L-PRP and P-PRP were significantly different from each other. A total of 33.438 peaks were found. Statistically significant (p<0.05) peaks were uploaded to the MetaboAnalyst 5.0 platform. Exogenous out of 2.308 metabolites were eliminated and metabolites found significant for our study were subjected to pathway analysis. Steroid biosynthesis, sphingolipid metabolism and metabolism of lipid pathways were affected. In the L-PRP samples, Nicotinamide riboside (FC: 2.2), MHPG (FC: 3.0), estrone sulfate (FC: 7.5), thiamine diphosphate (FC: 2.0), leukotriene E4 (FC: 7.5), PC(18:1 (9Z)e/2:0) (FC: 9.8) and Ap4A (FC: 2.1) were higher compared to P-PRP. C24 sulfatide (FC: −11.8), 3-hexaprenyl-4,5-dihydroxybenzoic acid (FC: −2.8) metabolites were furthermore lower in P-PRP. Clinical outcomes of PRP application should consider these metabolic pathways in future studies (2).

Background:. Blood loss, pain and wound healing contribute significantly to the perioperative morbidity after total knee arthroplasty. Prospective randomized controlled studies are lacking, to our knowledge. The purpose of this study was to determine whether platelet rich plasma (PRP) might prevent blood loss and postoperative pain and expedite wound healing following TKA. Methods:. Forty consecutive age, sex and BMI-matched patients who had unilateral or bilateral arthritis of the knee with similar deformity and preoperative range of motion were enrolled for this prospective randomized controlled double blinded clinical trial. Preoperative haemoglobin, range of motion, WOMAC and KSS scores were noted. Platelet-rich plasma was applied over the wound including the capsule, medial and lateral recesses in seventeen patients. Twentythree served as controls. Postoperative haemoglobin, blood loss, blood transfusion, VAS score, Wound score, KSS and WOMAC score were recorded and evaluated. Results:. Autologous platelet gel (APG) group had a smaller decrease in haemoglobin (Preop Hb–POD3 Hb) compared to control (1.97/3.56; p = 0.00). Postoperative blood loss was 173.2 ml vs 220.4 ml (p = 0.02). Blood transfusion was significantly less in the APG group (0.59 units/1.43 units; p = 0.001). APG group experienced less pain immediately, at 6 weeks and 12 weeks postoperatively (VAS 6.5/7.39, 2.67/3.84, 1.61/2.31; p = 0.00, 0.00, 0.00) and required fewer narcotics than control (15.24/22.65; p = 0.00). There was statistically significant difference in ROM at 5. th. day, 6 weeks and 3 months (79.44°/74.22°, 96.11°/87°, 97.6°/93.9° respectively; p = 0.00, 0.00, 0.01). There was no significant difference in the wound scores of two groups (30.96/34.23; p = 0.311). Significant difference was observed in KSS and WOMAC scores at 6 weeks (158.96/148.77, 17.3/23; p = 0.00, 0.00) and 12 weeks (166.96/161.42, 10.86/14.61; p = 0.00, 0.00). However no significant difference was found at 6 months. Conclusions:. We found significant reduction in blood loss, postoperative pain and need for narcotics after the use of autologous platelet gel in patients of total knee arthroplasty. Quicker and better functional outcome was observed in the APG group. However, at six months and later follow up, both groups had similar functional scores. Its role on wound healing was statistically insignificant. Level of Evidence: Therapeutic Level II

Background

Disability and slow return to sport and work after tendon rupture are major challenges. Platelet Rich Plasma (PRP) is an autologous supraphysiological concentration of platelets from whole blood that has demonstrated positive cellular and physiological effects on healing in laboratory conditions but evidence from adequately powered robust clinical trials is lacking. We aimed to determine the clinical efficacy of PRP for treatment of acute Achilles tendon rupture.

Background

The PATH-2 trial found no evidence of a benefit of Platelet Rich Plasma (PRP) injection versus a placebo after Achilles tendon rupture (ATR) at six-months. ATR often leave longer-term functional deficiencies beyond six-months. This study aim is to determine if PRP affect tendon functional outcomes at two-years after rupture.

Background. A cell-based tissue-engineered construct can be employed for treating meniscal lesions occurring in the non-vascularized inner two-thirds. The objective of this study was to test the hypothesis that both pre-differentiation of human bone marrow derived stromal cells (hBMSCs) into chondrogenic lineage before cell seeding and platelet-rich plasma (PRP) pretreatment on a PLGA mesh scaffold enhances the healing capacity of the meniscus with hBMSCs-seeded scaffolds in vivo. Methods. PRP of 5 donors was mixed and used for the experiments. The woven PLGA mesh scaffold (VicrylTM, Ethicon) measuring 20×8 mm (thickness, 0.2 mm) was prepared. The scaffolds were immersed into 1,000 μl of PRP and were centrifuged at 150g for 10 min. Then, the scaffold was flipped 180° and the same procedure was done for the other side. After washing, the scaffolds were soaked into 1,000 μl of DMEM media. hBMSCs from an iliac crest of 10 patients after informed consent and approval of our IRB were induced into chondrogenic differentiation with chondrogenic media containing 10 ng/ml rhTGF-ß3 in 1.2% alginate bead culture system for 7 days. Then, 2×10. 5. hBMSCs were recovered, seeded onto the scaffold, and cultured under dynamic condition. Based on the presence of pre-differentiation into chondrogenic lineage and the PRP pretreatment, 4 study groups were prepared. (no differentiation without PRP, no differentiation with PRP, chondrogenic differentiation without PRP, chondrogenic differentiation with PRP) Cell number for each cell-seeded scaffold was determined at 24 hours after seeding. Then, scaffolds were placed between human meniscal discs and were implanted subcutaneously in nude mice for 6 weeks (n=10 per group). Results. Cell attachment analysis revealed no significant difference among groups (p>0.05). The average cell number attached on the scaffold was ranged 1.1×10. 5. to 1.2×10. 5. among groups after 24 hours, so the initial cell seeding efficiency was ranged 55 to 60%. Histologic results from the 10 constructs containing hBMSCs undifferentiated and seeded onto non-PRP treated scaffolds revealed none had healed at all. Of the constructs containing hBMSCs undifferentiated and seeded onto PRP-pretreated scaffolds, three menisci healed and seven did not heal. Of the constructs containing hBMSCs pre-differentiated into chondrogenic lineage and seeded onto non-PRP treated scaffolds, six menisci healed and four did not heal. Of the constructs containing hBMSCs pre-differentiated into chondrogenic lineage and seeded onto PRP-pretreated scaffolds, seven menisci healed and three did not heal. Histological evaluation demonstrated a continuous hypercellular new fibrous tissue integrating into the native devitalized meniscus disc tissue in healed samples. The histological outcome between the groups was significant (p<0.05) (Table 1) (Figure 1). Conclusion. hBMSCs, which were differentiated into chondrogenic lineage before cell seeding and attached PRP-pretreated PLGA mesh scaffolds, demonstrated enhanced healing capacity of human meniscus in a meniscal repair mouse model. These findings demonstrate that both pre-differentiation of hBMSCs into chondogenesis and the PLGA scaffold modified by PRP pretreatment provides more biomimetic and biocompatible strategy for cell-mediated meniscal repair. Acknowledgements. This study was supported by Basic Science Research Program through the National Research Foundation of Korea (#2015-01004099)

Introduction. Osteochondral defects (OCDs) of the talus are treated initially by arthroscopic bone marrow stimulation. For both large and secondary defects, current alternative treatment methods have disadvantages such as donor site morbidity or two-stage surgery. Demineralized bone matrix (DBM) was published for the treatment of OCDs of rabbit knees. Autologous platelet-rich plasma (PRP) may improve the treatment effect of DBM. We previously developed a goat model to investigate new treatment methods for OCDs of the talus. The aim of the current study was to test whether DBM leads to more bone regeneration than control OCDs, and whether PRP improves the effectiveness of DBM. Methods. A standardized 6-mm OCD was created in 32 ankles of 16 adult Dutch milk goats. According to a randomized schedule, 8 goats were treated with commercially available DBM (Bonus DBM, Biomet BV, Dordrecht, the Netherlands) hydrated with normal saline, and 8 were treated with the same DBM but hydrated with autologous PRP (DBM+PRP). The contralateral ankles (left or right) were left untreated and served as a control. The goats were sacrificed after 24 weeks and the tali were excised. The articular talar surfaces were assessed macroscopically using the international cartilage repair society (ICRS) cartilage repair assessment, with a maximum score of 12. Histologic analysis was performed using 5-μm sections, and histomorphometric parameters (bone% and osteoid%) were quantified on representative areas of the surface, center, and peripheral areas of the OCDs. Furthermore, μCT-scans of the excised tali were obtained, quantifying the bone volume fraction, trabecular number, trabecular thickness, and trabecular spacing in both the complete OCDs and the central 3-mm cylinders. Results. All goats recovered well and were able to bear full weight within 24 hours after surgery. The mean ICRS-score of the ankles treated with DBM was 8.0 ± 1.0, compared to a score of 8.4 ± 1.5 in the contralateral ankle (NS); those treated with DBM+PRP scored 6.9 ± 2.4, compared to 7.4 ± 2.0 in the contralateral ankle (NS). Histologic analysis showed four different patterns of healing, distributed evenly over the treatment and control groups: type 1 (n = 4), almost completely healed; type 2 (n = 11), restoration of the subchondral bone with a cystic lesion underneath; type 3 (n = 14), superficial defect with regeneration from the margins and bottom; type 4 (n = 3), no healing tendency. Histomorphometry and μCT revealed no statistically significant difference between treatment (DBM or DBM+PRP) and contralateral control or between both treatment groups in any of the parameters investigated. Conclusion. No treatment effect of DBM was found compared to control defects, and the addition of PRP was not beneficial

Aim: This study wants to investigate whether the administration of stromal stem cells (SSC) in a platelet-rich plasma (PRP) scaffold could promote angiogenesis which resulted in a better allograft integration. Methods: surgery: A monolateral resection of 3cm segment of the metatarsus, was perfomed in 10 adult cross-breed sheep (3–4 years old), weighting 60–70 kg. Isolation and ex-vivo expansion of SSC: nucleated cells were isolated with density gradient and expanded ex-vivo with alpha-MEM containing 20% FCS. Radiographic and histomorphometric analysis: Radiographs were made after surgery and after 1, 2 and 4 months. Histomorphometric studies were carried out to study the defect and the new bone formation at the implant site. Results: Union had occurred in all the 5 animals of the SSC group after 4 months as observed radiographically and morphologically, while in the control group the osteotomy line was still visible. Histomorphometric analysis demonstrated a higher % of new-bone formation in both the host (%section quadrant) and the grafted bone in SSC animals. Conclusions: Results presented suggest that SSC in PRP-based scaffold have improved allograft integration. In conclusion the application of this surgical approach may result in an increased and accelerated bone graft integration, reducing the time required for bone healing and increasing the chances of a successful bone implant

Abstract

The reconstruction of large bone segments is a major goal in orthopaedic surgery. Autologous cancellous bone is recognized as the most biologically active graft material, but autologous bone harvest is associated with significant morbidity and founds its limit in the available quantity. Biomaterials or allografts do not encounter these limitations, but have no osteogenic and limited osteinductive potential. In order to enhance tissue regeneration and healing we have tried to obtain a graft with osteconductive, inductive and osteogenic properties. The day before operation 350 cc of autologous blood is donated from the patient and centrifuged to obtain a platelet-rich plasma. Bone marrow is aspirated from the posterior iliac crests with the patient under spinal anaesthesia and is processed to increase its stem cell content. The structural scaffold used is morcellized cancellous bone provided from our Bone Bank. At operation bone is mixed with bone marrow buffy coat and Platelet Rich Plasma in a sterile glass becker with addition of CaCl2 till clot formation to produce a gel-like component that is handled easily. We have utilized this technique from November 2000 till January 2004 for 68 patients: 41 of these patients required healing of large bone defects: 22 males and 19 females. Fresh bone marrow alone was used for a percutaneous injection in 11 cases; open surgery with autologous growth factors, bone marrow buffy coat and allograft was used in 30 patients. The radiological and clinical results showed early healing of the defects treated with this technique and no complications related to the procedure at an average follow up of 23 months (3–40)

Introduction

Collapse of femoral head associated with end-stage arthritis form hallmark of osteonecrosis of femoral head. Purpose was to assess efficacy of platelet rich plasma following core decompression in early stage of osteonecrosis of femoral head.

Rotator cuff disease encompasses a spectrum from partial to full thickness tears. Despite being 2–3 times more common than full–thickness tears, effective non-operative treatment for partial thickness tears has remained elusive. Platelet enriched plasma (PRP) has been proposed to enhance rotator cuff healing by enhancing the natural healing cascade. However, its utility in rotator cuff disease remains controversial. The purpose of this study was to compare the patient reported outcomes between PRP and corticosteroid injection in patients with symptomatic partial thickness tears.

This double blind randomized controlled trial enrolled patients with symptomatic, partial thickness rotator cuff tears or rotator cuff tendinopathy proven on ultrasound or MRI. Patients were randomized to either corticosteroid or PRP ultrasound-guided injection of the affected shoulder. Patients completed patient reported outcomes at 6 weeks and 12 weeks. The primary outcome was Visual Analog Scale (VAS) pain scores. Secondary outcomes included the Western Ontario Rotator Cuff (WORC) index, American Shoulder and Elbow Surgeons (ASES) score, and failure of non-operative management as determined by consent for surgery or progression to operative intervention.

Ninety-nine patients were enrolled in the study with equal demographics between the two groups. Taking into account pre-injection scores, patients with PRP injections demonstrated a statistically significant improvement in VAS scores compared to patients receiving corticosteroid injections at 12 weeks (p=0.045) but not at 6 weeks (p=0.704). There was no difference in other outcome measures or progression of the two groups to surgical intervention.

The use of PRP in the management of partial thickness rotator cuff tears demonstrates significant improvement of pain scores at 12 week follow up compared to corticosteroid injections. However, this did not affect the rate of progression to surgical intervention. Continued study is required to determine the utility of PRP in this patient population.

Introduction and Objective

Platelet-Rich-plasma (PRP) has been used in combination with stem cells, from different sources, with encouraging results both in vitro and in vivo in osteochondral defects management. Adipose-derived Stem Cells (ADSCs) represents an ideal resource for their ease of isolation, abundance, proliferation and differentiation properties into different cell lineages. Furthermore, Stem Cells in the adipose tissue are more numerous than from other sources. Aim of this study was to evaluate the potential of ADSCs in enhancing the effect of arthroscopic mesenchymal stimulation combined with infiltration of PRP.

Introduction

Lateral epicondylitis, also known as “tennis elbow,” is a degenerative disorder of the common extensor origin of the lateral humeral epicondyle. The mainstay of treatment is non-operative and includes physiotherapy, activity modification, bracing, nonsteroidal anti-inflammatory drugs, and injections. There is a subgroup of patients however who do not respond to non-operative measures and require operative intervention.

Injured skeletal muscle repairs spontaneously via regeneration, however, this process is often incomplete because of fibrotic tissue formation. In our study we wanted to show improved efficiency of regeneration process induced by antifibrotic agent decorin in a combination with Platelet Rich Plasma (PRP)-derived growth factors. A novel human myoblast cell (hMC) culture, defined as CD56 (NCAM)+ developed in our laboratory, was used for evaluation of potential bioactivity of PRP and decorin. To determine the their effect on the viability of hMC we performed a MTT assay. To perform the cell proliferation assay, hMCs were separately seeded on plates at a concentration of 30 viable cells per well. Cell growth medium prepared with different concentrations of PRP exudates (5%, 10%, and 20%) and decorin (10 ng/mL, 25 ng/mL, and 50 ng/mL) were added and incubated for 7 days. After incubation we stained the cells with crystal-violet and measured the absorbance.

To study the expression of Transforming Growth Factor Beta (TGF-β) and myostatin (MSTN), two main fibrotic factors in the process of muscle regeneration we performed several ELISA assays in groups treated with all therapeutic agents (PRP, decorin and their combination). Further, we have studied the ability of these agents to influence the differential cascade of dormant myoblasts towards fully differentiated myotubes by monitoring step wise activation of single nuclear factors like MyoD and Myogenin via multicolor flow cytometry. We stained the cells simultaneously with antibodies against CD56, MyoD and myogenin. We acquired cell images of 5,000 events per sample at 40 x magnification using 488 nm and 658 nm lasers and fluorescence was collected using three spectral detection channels. We analysed the cells populations according to expression of single or multiple markers and their ratios.

Finally, we examined the treated cell populations using a multicolour laser microscope after staining for desmin (a key marker of myogenic differentiation of hMC), α-tubulin, and nuclei. Optical images were acquired at the center of chamber slides where the cell density is at its highest using a Leica TCS SP5 II confocal microscope and analysed using Photoshop CS6, where a “Color Range” tool was used in combination with a histogram palette to count the pixels that correspond to desmin-positive areas in an image.

The mitochondrial activity of cells, as determined by the MTT assay, was significantly increased (p < 0 .001) after exposure to tested concentrations of PRP exudate. Similarly, viability was elevated in all tested concentrations of decorin. PRP exudate enhanced the viability of cells to more than 400% when compared to the control (p < 0 .001). The viability of cells treated with PRP exudates was also significantly higher when compared to decorin (p < 0 .001). Decorin did not show a significant effect on cell proliferation compared to the control, however, cultivation with PRP exudate leads to a 5-fold increase in cell proliferation (p < 0 .001). Decorin was shown to down-regulate the expression of TGF-β when compared to the control by more than 15% (p < 0 .001) but significantly less than PRP exudate p < 0 .005). PRP significantly down-regulated TGF-β expression by more than 30% (p < 0 .001). Similarly, the MSTN expression levels were significantly down-regulated by decorin and PRP. MSTN levels of cells treated with decorin were decreased by 28.4% (p < 0 .001) and 23.1% by PRP (p < 0 .001) when compared to the control group.

Using flow cytometry we detected a 39.1% increase in count of myogenin positive cells in the PRP-treated group compared to the control. Moreover, there was a 3.09% increase in cells positive only for myogenin, whereas no such cells were found in the control cell population. The population of cells positive only for myogenin is considered as fully differentiated and capable of fusion into myotubes as well as future mucle fibers and is thus of great importance for muscle regeneration. At the same time 20.6% fewer cells remained quiescent (positive only for CD56). Cells positive for both MyoD and myogenin represent the population that shifted significantly towards mature myocites during myogenesis but are not yet fully committed.

Finally, a statistically significant up-regulation of desmin expression (p < 0 .01 for the PRP treated group, p < 0 .005 for the decorin and PRP + decorin treated groups) was present in all therapeutic groups when compared to the control. While no significant difference was found between the PRP and decorin-treated groups, their combination led to a more than 3-fold increase (p < 0 .005) of desmin expression when compared to single bioactives.

PRP can be a highly potential therapeutic agent for skeletal muscle regeneration and repair, especially if in combination with a TGF-β antagonis decorin. Achieving better healing could likely result in faster return to play and lower reinjury rate.

The aim of this study was to evaluate the trochlear bone and cartilaginous regeneration of rabbits using a composite based on platelet rich plasma (PRP), chitosan and hydroxyapatite. The study was approved by the ethics committee of the Federal University of Campina Grande under number 72/2017. Surgical holes measuring four millimetres in diameter were performed in rabbit trochleae, one surgical hole in each animal remained empty and another one was filled with the composite. Clinical-orthopaedic and radiographic evaluations were carried out for 60 days, after which the animals were euthanized for histomorphometric evaluations. Clinical-evaluations exhibited lameness of two members of the treatment (T) group and one member of control (C) group. The radiographic evaluation of T group exhibited absence of subchondral bone reaction (33%); nonetheless, presence of moderate subchondral bone reaction was more frequently reported in group C with 67%. Microscopic evaluation revealed the presence of tissue neoformation, composed of dense connective tissue. Microscopic findings were similar in both groups, with a difference in the amount of neoformed tissue, which was confirmed after the morphometric analysis, revealing a significant difference in the quantity of newly formed tissue at the bone / cartilage / implant interface in the T group. The results indicate that the composite based on chitosan, hydroxyapatite and PRP enhanced bone and cartilage healing.

Angiogenesis is a key factor in early stages of wound healing and is crucial for tissue regeneration. Gold standard for large bone defect treatment is the transplantation of autologous bone grafts, but is not entirely satisfying (e.g. limited amount). Cell therapies and tissue engineering approaches may overcome these problems by using cells and autologous blood components obtainable by less invasive procedures. Pre-clinical studies previously showed promising results combining endothelial progenitor cells (EPCs) and mesenchymal stem cell (MSCs) in polyurethane scaffolds in presence of PRP (1). A systemic investigation of the chemical and mechanical characteristics of different PRP gels formulations suggested their potential use as sustained autologous growth factor delivery system (2). Here we investigate PRP hydrogels as autologous injectable cell delivery systems for EPCs and MSCs and their efficacy in promoting fast neo-vascularization for bone repair applications.

PRP hydrogel and corresponding platelet lysate (PL) were produced from platelet concentrates as described before (3). MSCs were isolated by Ficoll-Paque centrifugation from human bone marrow (EK_regensburg12-101-0127), and cultured in alpha MEM containing 10% FCS and 5 ng/mL basic-FGF (GIBCO). EPCs (CD133+/CD34+) were isolated from MSC fractions using magnetic-activated cell sorting (MACS®) and further cultured in IMDM (GIBCO) containing 5% FCS and 5% PL. GFP positive HUVECs are from Angio-Proteomie, (Boston, USA). Prior to gel encapsulation, MSC and EPCs were pre-stained using PKH26-red® and PKH67-green® respectively. Cells in different proportions were encapsulated in 3D PRP gels, in FDA approved Fibrin gels and in Matrigel®. The gels were cultured in Ibidi microwells placed in an onstage incubator linked to an EVOS Auto Cell Imaging System. The cellular network formation capacity of HUVEC or EPCs and MSC in different proportions was analyzed for the 3 types of hydrogels using time lapse movies recorded over a period of 14 days. Parallel cultures were performed in a classical cell culture CO₂ incubator and sample gels were taken at different time points for additional immunostaining and gene expression analysis.

Preliminary results indicate high cell viability in all of the three tested gels. PRP hydrogels present a favorable environment for the formation of a 3 dimensional cellular network in cell co-culture. The formation of these networks was apparent as early as 4 days after seeding. Networks increase in complexity and branching over time. The same was observed when cells were embedded in Matrigel®, which is known for its pro-angiogenic properties. Further experiments are currently in process looking at the involvement of MSCs in this process and the effect of PRP 3D co-culture on their differentiation.

PRP was previously shown as a potent growth factor delivery system for tissue engineering. In the present work, the high cell viability together with the 3 dimensional capillary-like networks observed at early time points suggest that PRP can also be used as an autologous cell delivery and pro-angiogenic system for bone tissue repair.

Platelet rich plasma has been advocated for the treatment of plantar fasciitis but there are few good quality clinical trials to support its use. We report a pilot double blind randomised controlled trial of platelet rich plasma versus normal saline.

Posterolateral spinal fusion (PSLSF) in rabbits is a challenging model for bone substitutes because the transverse processes are extremely thin and the space to be filled with bone is greater than critical and meiopragic in terms of vascularity.

Several investigators have shown beneficial effects of PRP in bone and soft-tissue healing processes. However, controversial results have been reported in clinical setting analysing the effectiveness of PRP. Aim of the present study was to test the effectiveness of PRP in experimental model of PLSF in rabbits.

Introduction: Activated platelets release various growth factors, some ot which are recognize to improve nerve regeneration. The present study evaluated the effect of platelet-rich-plasma (PRP) in end to end neurorraphy.

Material and method: A total of 38 Spragle-Dawley rats were used. The PRP was obteined from each rat and applicated to the same rat. The left hind limb were used as experimental, with the right as control. The animals were treated in two grups. In both groups the sciatic nerve was dissected from the sciatic notch to the bifurcation. The nerve was transected an repaired with epineural suture (ethilon 9–0). Group A (n=12): suture without PRP. Group B (n=15) suture with PRP. The rats were anestherized and electromyographic studie was performed after the following, 120,5 days for group A and 125,86 for group B. Prior to sacrifice muscular and nerve tissue harvesting was performed.

The amplitude was expressed as the amplitude at the experimental sde divided by the amplitude at the contralateral, untreated side, multiplied by 100%. Recording was done in gastrocnemius and tibialis anterior muscle.

Results: The stimulation was performed in supramaximal form on both groups: Group A: (without PRP)

The mean of intensity was 1.49 mA and the mean of threshold was 0,56 mA

No stadistical difference on both groups was found.

Histological studies were performed and results are no available at the moment of send this abstract

Conclusions:

No evidence has been found that the use of PRP has a beneficial effect on peripheral nerve regeneration

Lateral Epicondylitis is a common condition caused by angiofibroblastic hyperplasia of the tendinous insertion. Its treatment is varied and includes rest, physiotherapy, corticosteroid injection and surgical release. Of late, the role of Platelet Rich Plasma (PRP) injections have been explored, with positive results.

We prospectively assessed the outcomes of lateral epicondylitis treated with PRP injections and compared the outcomes of ultrasound guided and ‘blind’ injection.

This was a single centre prospective cohort study. Patient were assessed with the Disabilities of the Arm, Shoulder and Hand (DASH) Score. PRP was injected into and around the common extensor origin either with or without ultrasound guidance. The primary outcome measure was DASH score at 3 months.

45 (23F:22M) patients were recruited. The mean age was 50 years (range 35 to 79). The mean duration of follow-up was 106 days. The average pre-injection DASH score for both groups combined was 45.5 (11.7–87.5). The mean DASH score at 3 months follow-up was 27.7. The ultrasound guided injection group had a mean improvement in DASH score from 45.5 to 31.2. The “blind” injection group had a mean improvement in DASH from 44.4 to 27.7. No complications were noted. There was no statistically significant difference in improvement in DASH score between the two groups.

Our study provides further evidence to support of the use of PRP injections in the treatment of epicondylitis of the elbow. Interestingly, however, we found that the use of Ultrasound guidance does not appear to improve patient outcomes.

Chronic plantar fasciitis is a common condition but can be difficult to successfully treat. Platelet rich plasma (PRP), a concentrated bioactive component of autologous blood rich in cytokines and other growth factors, was compared with cortisone injection in the treatment of severe cases of plantar fasciitis resistant to traditional non-operative paradigms. Thirty-six patients (16 males 20 females) were prospectively randomized into two study groups. All patients had pre-treatment MRI and ultrasound studies consistent with plantar fasciitis. The first group was treated with a single ultrasound guided injection of 40 mg Depo-Medrol at the injury site and the second group was treated with a single ultrasound guided injection of un-buffered autologous PRP at the injury site. The cortisone group had an average age of 59 (24–74) and had failed 4 months (3–24) of standard non-operative management (rest, heel lifts, PT, NSAIDS, cam walker immobilization, night splinting, local modalities) and had pre-treatment AOFAS scores of 52 (24–60). The PRP group had an average age of 51 (21–67) and had failed 5 months (3–26) of standard non-operative management (rest, heel lifts, PT, NSAIDS, cam walker immobilization, night splinting, local modalities) and had pre-treatment AOFAS scores of 37 (30–56). All patients were then immobilized fully weight bearing in a cam walker for 2 weeks, started on eccentric home exercises and allowed to return to normal activities as tolerated and without brace support. Post-treatment AOFAS scores were PRP 95 (84–100) and cortisone 81(60–90) at 3 months (CI 95% p< .0001), PRP 95 (86–100) and cortisone 81 (60–90) at 6 months (CI 95% p< .0001), and PRP 94 (86–100) and cortisone 58 (45–77) at 12 months (CI 95% p< .0001). Platelet rich plasma injection is more effective and durable than cortisone injection for the treatment of severe chronic plantar fasciitis refractory to traditional non-operative management.

Autologous injection of platelet rich plasma (PRP) stimulates healing process in degenerated tendons. The purpose of this study is to compare the functional outcome of lateral epicondylitis treated with PRP and steroid injection.

Tennis elbow patients who failed conservative medical therapy were included and were allocated randomly steroid group (n=70) and PRP group (n=63). Data were collected before procedure, at 4, 8, 12 weeks, 1 year and 2 years after procedure. The main outcome measures were visual analogue score, Mayo elbow performance score, DASH score and hand grip strength.

Successful treatment was defined as more than a 25% reduction in visual analogue score or DASH score and more than 75 score in Mayo elbow performance score. We observed that 35 of the 70 patients (50%) in corticosteroid group and 47 of the 63 patients (75%) in PRP group were successful, which was significantly different (p<.001), according to DASH score 37 of the 70 patients (53%) and 47 of the 63 patients (75%) in the PRP group were successful which was also significantly different (P = .005), Mayo elbow performance score was successful in 36 of the 70 patients (51%) in corticosteroid group and 49 of the 63 patients (78%) in PRP group. The improvement in hand grip strength of hand from 24.7kg (mean) 26kg in corticosteroid group and 23.5kg (mean) to 32.9kg (mean) in PRP group.

PRP injection for chronic lateral epicondylitis reduces pain, improve functionality and hand grip strength when compared to steroid injection.

Summary Statement

An autologous thrombin activated 3-fold PRP, mixed with a biphasic calcium phosphate at a 1mL:1cc ratio, is beneficial for early bone healing in older age sheep.

The February 2023 Research Roundup. 360. looks at: Clinical and epidemiological features of scaphoid fracture nonunion; Routine sterile glove and instrument change at the time of abdominal wound closure to prevent surgical site infection (ChEETAh); Characterization of genetic risk of end-stage knee osteoarthritis treated with total knee arthroplasty; Platelet-rich plasma or autologous blood injection for plantar fasciitis; Volume and outcomes of joint arthroplasty; The hazards of absolute belief in the p-value laid bare

Aims. Intra-articular (IA) injection may be used when treating hip osteoarthritis (OA). Common injections include steroids, hyaluronic acid (HA), local anaesthetic, and platelet-rich plasma (PRP). Network meta-analysis allows for comparisons between two or more treatment groups and uses direct and indirect comparisons between interventions. This network meta-analysis aims to compare the efficacy of various IA injections used in the management of hip OA with a follow-up of up to six months. Methods. This systematic review and network meta-analysis used a Bayesian random-effects model to evaluate the direct and indirect comparisons among all treatment options. PubMed, Web of Science, Clinicaltrial.gov, EMBASE, MEDLINE, and the Cochrane Library were searched from inception to February 2023. Randomized controlled trials (RCTs) which evaluate the efficacy of HA, PRP, local anaesthetic, steroid, steroid+anaesthetic, HA+PRP, and physiological saline injection as a placebo, for patients with hip OA were included. Results. In this meta-analysis of 16 RCTs with a total of 1,735 participants, steroid injection was found to be significantly more effective than placebo injection on reported pain at three months, but no significant difference was observed at six months. Furthermore, steroid injection was considerably more effective than placebo injection for functional outcomes at three months, while the combination of HA+PRP injection was substantially more effective at six months. Conclusion. Evidence suggests that steroid injection is more effective than saline injection for the treatment of hip joint pain, and restoration of functional outcomes. Cite this article: Bone Joint J 2024;106-B(6):532–539

The April 2023 Knee Roundup. 360. looks at: Does bariatric surgery reduce complications after total knee arthroplasty?; Mid-flexion stability in total knee arthroplasties implanted with kinematic alignment: posterior-stabilized versus medial-stabilized implants; Inflammatory response in robotic-arm-assisted versus conventional jig-based total knee arthroplasty; Journey II bicruciate stabilized (JII-BCS) and GENESIS II total knee arthroplasty: the CAPAbility, blinded, randomized controlled trial; Lifetime risk of revision and patient factors; Platelet-rich plasma use for hip and knee osteoarthritis in the USA; Where have the knee revisions gone?; Tibial component rotation in total knee arthroplasty: CT-based study of 1,351 tibiae