Orthobiologics

The use of platelet-rich plasma in pathologies of the foot and ankle: A comprehensive review of the recent literature

Platelet-rich plasma (PRP) is an autologous serum containing higher concentrations of platelets and growth factors above normal blood. The process of obtaining PRP involves the extraction of blood from the patient which is then centrifuged to obtain a concentrated suspension of platelets. PRP continues to evolve as a potential treatment modality with many applications in orthopaedic surgery. The therapeutic components of PRP possess numerous theoretical regenerative properties. The present manuscript outlines how PRP is prepared, noting the tremendous variability between preparation protocols. Given the growing body of evidence examining the use of PRP in pathologies of the foot and ankle, we assess its efficacy as it relates to our field. Specifically, we evaluate the literature in the past five years regarding the role of PRP in treating plantar fasciitis, Achilles tendinopathy, insertional Achilles tendinitis, Achilles tendon ruptures, osteochondral lesions of the talus, hallux rigidus, and ankle osteoarthritis.

Efficacy of Platelet-Rich Plasma in Soft Tissue Foot and Ankle Pathology

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The preparation methodology for platelet-rich plasma (PRP) may have important clinical implications with varying effectiveness with leukocyte, platelet, and growth factor concentrations.

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There is high-quality evidence to support the superiority of PRP over corticosteroids in the case of chronic plantar fasciitis.

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There is moderate-quality to high-quality evidence for PRP's ability to increase tendon thickness with no capacity to decrease pain, increase function, or augment percutaneous tenotomy in Achilles tendinopathy.

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There is insufficient evidence to support PRP injections in the definitive treatment of Achilles tendon rupture. However, PRP may contribute to postoperative recovery after tendon rupture repair, but this requires further research.

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The biochemical theory supporting the clinical use of PRP must be reinforced with high-level evidence research. Based on the current literature, PRP may serve as a viable treatment method in chronic plantar fasciitis. Further high-quality, comparative studies with longer clinical follow-up are required to support recommendations for use of PRP in the treatment of Achilles tendon pathology.

Activated Serum Increases In Vitro Cellular Proliferation and Growth Factor Expression of Musculoskeletal Cells

The purpose of this study was to investigate proteomic alteration that occurs to whole blood when converted to activated serum (AS) using an autologous thrombin system. This study further sought to evaluate the functional in vitro effect of AS on tenocytes, chondrocytes, subacromial bursal cells, and osteoblasts. The peptide/protein composition of AS was analyzed by liquid chromatography−mass spectrophotometry (LC-MS). The cell lines were treated with AS, and cellular proliferation was quantified 48 h after treatment. Platelet-derived growth factor (PDGF), insulin-like growth factor 1 (IGF-1), vascular endothelial growth factor (VEGF), interleukin-1 beta (IL-1β), and interleukin-1 receptor antagonist (IL-1Ra) were quantified utilizing enzyme-linked immunosorbent assays (ELISAs). LC-MS identified 357 proteins across the AS and whole blood. Fifty-four of the proteins identified had significant differences between the relative protein abundance of the AS samples compared to whole blood. Treatment with AS in all cell lines significantly increased proliferation compared to control cells at 48 h. Increased PDGF, VEGF, and IGF-1 in all cell lines exposed to AS compared to the control (p < 0.05) were observed. These findings suggest that treatment with AS increases in vitro cellular proliferation and the release of growth factors that may play a role in tissue repair.

Orthobiologics in Foot and Ankle Arthrodesis: A Systematic Review

Orthobiologics are biologically-derived materials intended to promote bone formation and union. We review evidence on effectiveness and harms of orthobiologics compared to no orthobiologics for foot and ankle arthrodesis. We searched multiple databases (1995-2019) and included clinical trials and other studies with concurrent controls, English language, and reporting patient-centered outcomes, union/time to union, costs/resource utilization, or harms. Studies were organized by orthobiologic used. We describe quality and limitations of available evidence but did not formally rate risk of bias or certainty of evidence. Most of the 21 studies included were retrospective chart reviews with orthobiologics used at surgeon's discretion for patients considered at higher risk for nonunion. Ten studies compared autologous bone graft versus no graft and 2 compared remote versus local graft with few studies of other orthobiologics. All studies reported a measure of fusion and about half reported on function/quality of life. Few studies reported harms. Due to limited reporting, we were unable to assess whether effectiveness varies by risk factors for nonunion (eg, age, gender, smoking status, obesity, diabetes) or whether orthobiologics were cost-effective. Available evidence is of poor quality with small sample sizes, inadequate reporting of risk factors for nonunion, variations in orthobiologics, surgical techniques used, and outcome assessment, and potential selection bias. Research is needed to adequately inform surgeons about benefits and harms and guide patient selection for use, or type, of orthobiologics. Careful assessment of individual patient risk for nonunion is critical prior to orthobiologic use.

Bone marrow aspirate clot: A feasible orthobiologic

Musculoskeletal disorders are one of the major health burdens and a leading source of disability worldwide, affecting both juvenile and elderly populations either as a consequence of ageing or extrinsic factors such as physical injuries. This condition often involves a group of locomotor structures such as the bones, joints and muscles and may therefore cause significant economic and emotional impact. Some pharmacological and non-pharmacological treatments have been considered as potential solutions, however, these alternatives have provided quite limited efficacy due to the short-term effect on pain management and inability to restore damaged tissue. The emergence of novel therapeutic alternatives such as the application of orthobiologics, particularly bone marrow aspirate (BMA) clot, have bestowed medical experts with considerable optimism as evidenced by the significant results found in numerous studies addressed in this manuscript. Although other products have been proposed for the treatment of musculoskeletal injuries, the peculiar interest in BMA, fibrin clot and associated fibrinolytic mechanisms continues to expand. BMA is a rich source of various cellular and molecular components which have demonstrated positive effects on tissue regeneration in many in vitro and in vivo models of musculoskeletal injuries. In addition to being able to undergo self-renewal and differentiation, the hematopoietic and mesenchymal stem cells present in this orthobiologic elicit key immunomodulatory and paracrine roles in inflammatory responses in tissue injury and drive the coagulation cascade towards tissue repair via different mechanisms. Although promising, these complex regenerative mechanisms have not yet been fully elucidated.