What Are Biologics in Orthopedic Surgery? A Complete Overview

The word “biologics” gets used loosely in orthopedic surgery. Depending on who’s talking, it might refer to bone graft substitutes packed into a spinal fusion cage, platelet-rich plasma injected into a tennis elbow, amniotic tissue applied to a rotator cuff repair, or stem cell concentrates delivered to an arthritic knee. These are fundamentally different products with different mechanisms of action, different regulatory classifications, different evidence profiles, and different price points. Lumping them together under one term creates confusion — for surgeons, for patients, and for the device representatives who sell them.

This article breaks down what biologics actually are in orthopedic surgery, how the major product categories work, where the evidence stands, and what the market looks like heading into 2026.

What Are Biologics in Orthopedic Surgery?

In the broadest sense, orthopedic biologics are products derived from biological sources — human tissue, blood components, growth factors, or bioengineered materials — that are used to promote healing, regeneration, or tissue repair in musculoskeletal applications. They stand in contrast to traditional implants (metal, PEEK, polyethylene) which provide mechanical function but don’t actively participate in the biological healing process.

The defining characteristic of biologics is that they interact with the body’s own healing mechanisms. They might provide a scaffold for bone to grow into (osteoconduction), stimulate bone formation through growth factor signaling (osteoinduction), deliver living cells capable of forming new bone (osteogenesis), or modulate the inflammatory environment to promote tissue repair.

The major categories of orthopedic biologics include:

• Bone grafts and bone graft substitutes
• Platelet-rich plasma (PRP)
• Bone marrow aspirate concentrate (BMAC) and stem cell products
• Amniotic and placental tissue products
• Growth factors (BMP-2, BMP-7, PDGF)
• Demineralized bone matrix (DBM)
• Synthetic scaffolds with biologic properties

Each category has its own mechanism, evidence base, regulatory pathway, and clinical niche. Understanding the differences is essential for anyone working in the orthopedic device space.

Bone Grafts and Bone Graft Substitutes

Bone grafting is the oldest and most established application of biologics in orthopedic surgery. The concept is simple: place material in or around a fracture, fusion site, or bone defect that promotes new bone formation.

Autograft

Autologous bone graft — bone harvested from the patient’s own body — remains the gold standard. Iliac crest bone graft (ICBG) is the most common source, providing cancellous bone that contains all three desirable properties: osteoconductivity (a scaffold for bone growth), osteoinductivity (growth factors that signal new bone formation), and osteogenicity (living osteoblasts and progenitor cells that can directly form new bone).

The problem with autograft is the harvest. Taking bone from the iliac crest requires a second surgical site, adds operative time, and creates donor site morbidity that can include chronic pain, infection, hematoma, nerve injury, and even pelvic fracture. Studies report that 10-30% of patients have significant donor site pain that persists beyond the recovery period. This is why the entire field of bone graft substitutes exists — to provide the benefits of autograft without the harvest.

Local autograft — bone collected during the surgical procedure itself, such as lamina and spinous process bone during a spinal decompression — avoids the second incision but provides limited volume and may have lower osteogenic potential.

Allograft

Allograft is cadaveric bone obtained from tissue banks. It is processed to remove cellular material and reduce immunogenicity and disease transmission risk. Depending on the processing method, allograft retains varying degrees of osteoconductive and osteoinductive properties.

Structural allograft (cortical rings, femoral rings, fibular struts) provides mechanical support and is used in situations where the graft needs to bear load immediately, such as anterior cervical corpectomy reconstruction. Cancellous allograft (chips, croutons) provides an osteoconductive scaffold and is used as a graft extender, often mixed with local autograft or bone marrow aspirate.

Demineralized Bone Matrix (DBM)

DBM is allograft bone that has been processed with acid to remove the mineral component, exposing the collagen matrix and endogenous growth factors, particularly BMPs. The result is a product with osteoinductive properties — it can stimulate new bone formation in the right biological environment — without the osteogenic capability of autograft.

DBM comes in various formulations: putty, gel, strips, paste, and injectable forms. Common products include Grafton (Medtronic), DBX (DePuy Synthes), and Accell (Integra). DBM is one of the most widely used biologic products in spine surgery, often used as a graft extender in posterolateral fusion.

Synthetic Bone Graft Substitutes

Synthetic options include calcium phosphate ceramics (beta-tricalcium phosphate, hydroxyapatite), calcium sulfate, and bioactive glass. These materials provide osteoconductive scaffolds that are resorbed and replaced by new bone over time. They eliminate disease transmission risk and supply constraints associated with allograft.

The trade-off is that synthetics lack osteoinductive and osteogenic properties. They work best in biologically favorable environments — healthy patients with good vascularity and stable fixation — where the body’s own healing response can populate the scaffold with bone-forming cells.

Platelet-Rich Plasma (PRP)

PRP is an autologous blood product made by drawing the patient’s blood and concentrating the platelet fraction through centrifugation. The concentrated platelets contain growth factors — including PDGF, TGF-beta, VEGF, and IGF-1 — that play roles in tissue healing and inflammation modulation.

In orthopedic surgery, PRP is used in two main contexts:

Injection therapy. PRP injections are widely used for tendinopathy (tennis elbow, patellar tendinopathy, Achilles tendinopathy), osteoarthritis (particularly knee OA), plantar fasciitis, and muscle injuries. The evidence for injection therapy is mixed and varies significantly by indication. For knee osteoarthritis, multiple randomized trials and meta-analyses have shown PRP injections provide greater and longer-lasting pain relief compared to hyaluronic acid or corticosteroid injections. For tendinopathy, the results are more variable depending on the specific tendon, the PRP formulation, and the preparation protocol.

Surgical augmentation. Some surgeons apply PRP to rotator cuff repairs, ACL reconstructions, fracture sites, or cartilage procedures to augment the healing response. The evidence for surgical augmentation is less established than for injection therapy, and practice varies widely.

One of the ongoing challenges with PRP is standardization. Different centrifugation systems produce different platelet concentrations, leukocyte content, and growth factor profiles. A “leukocyte-rich” PRP preparation is biologically different from a “leukocyte-poor” preparation, and the optimal formulation likely varies by indication. This variability makes it difficult to compare studies and draw definitive conclusions about efficacy.

Stem Cell and Bone Marrow Aspirate Concentrate

Bone marrow aspirate concentrate (BMAC) is produced by aspirating bone marrow — typically from the posterior iliac crest — and concentrating it through centrifugation. The resulting concentrate contains mesenchymal stem cells (MSCs), hematopoietic stem cells, growth factors, and cytokines.

The mesenchymal stem cells in BMAC have the ability to differentiate into bone, cartilage, and other connective tissues, which is the theoretical basis for using BMAC in orthopedic applications. It is used as a bone graft supplement in spinal fusions (combined with an osteoconductive scaffold), applied to cartilage defects, injected into osteoarthritic joints, and used to augment tendon and ligament repairs.

The term “stem cell therapy” is frequently misused in orthopedic marketing. True stem cell therapies involving culture-expanded cells are regulated as drugs by the FDA and require an Investigational New Drug (IND) application. BMAC, by contrast, is a minimally manipulated autologous tissue product that falls under different regulatory guidelines (21 CFR Part 1271) and can be used as a point-of-care procedure without FDA premarket approval, provided it meets the criteria for minimal manipulation and homologous use.

The distinction matters enormously. Clinics marketing “stem cell injections” for orthopedic conditions are often using BMAC or adipose-derived cellular products, and the marketing language sometimes overstates the evidence and conflates these point-of-care preparations with the cultured stem cell therapies being studied in clinical trials.

The evidence base for BMAC in orthopedic surgery is growing but incomplete. For bone healing augmentation in spinal fusion and fracture nonunion, the data is generally supportive. For cartilage regeneration and osteoarthritis treatment, the evidence is more preliminary, and well-powered randomized controlled trials with long-term follow-up are still needed.

Amniotic Tissue Products

Amniotic tissue products derived from human placental tissue have become one of the fastest-growing segments of the orthopedic biologics market. These products include amniotic membrane, amniotic fluid, and combinations of both, processed and preserved in various forms — dehydrated, cryopreserved, or lyophilized.

The biological rationale for amniotic tissue is its unique composition. Amniotic membrane contains collagen, growth factors (including TGF-beta, bFGF, EGF, and PDGF), hyaluronic acid, and anti-inflammatory cytokines. It is immunologically privileged, meaning it does not typically trigger an immune rejection response. These properties make it useful as an anti-inflammatory, anti-scarring, and healing-promoting agent.

In orthopedic and sports medicine applications, amniotic tissue products are used for soft tissue repair augmentation (rotator cuff, Achilles tendon), joint inflammation reduction, wound coverage over surgical sites, and as a biologic adjunct in tendon and ligament procedures.

Products like AmnioFix (MiMedx), Clarix (Amniox/Solstas), and various other branded amniotic tissue products have gained significant market share. The regulatory pathway for these products varies — some are regulated as human cells, tissues, and cellular and tissue-based products (HCT/Ps) under Section 361 of the Public Health Service Act, while others may require premarket approval depending on their intended use and level of processing.

The evidence base is growing but still needs more high-quality randomized trials. Early clinical data is promising for specific applications, particularly in reducing inflammation and promoting soft tissue healing, but the field would benefit from larger trials with standardized protocols and longer follow-up periods.

Growth Factors: BMP and Beyond

Recombinant growth factors represent the most potent osteoinductive biologics available. BMP-2 (recombinant human bone morphogenetic protein-2), marketed as Infuse by Medtronic, was FDA-approved in 2002 for anterior lumbar interbody fusion and has been the most commercially significant growth factor product in orthopedic surgery.

BMP-2 is undeniably effective at producing bone. In its approved indication — single-level ALIF with a specific cage — it demonstrated fusion rates comparable to iliac crest autograft without the donor site morbidity. The problem was what happened when it was used off-label, which accounted for the majority of its clinical use during its peak years.

Off-label use of BMP-2 in the posterior cervical spine, at high doses in the lumbar spine, and in other applications not studied in the original trials led to reports of serious complications: heterotopic bone formation causing nerve compression, inflammatory reactions, osteolysis around cages, and retrograde ejaculation in anterior lumbar procedures. High-profile investigations by the Spine Journal in 2011 revealed that the original industry-sponsored studies had underreported adverse events.

The fallout reshaped how the orthopedic community views growth factor biologics. BMP-2 use has declined substantially from its peak. When used appropriately — at recommended doses, in approved or well-studied indications — it remains a useful tool. But the experience served as a cautionary tale about the gap between a product’s biological potency and its clinical safety profile when used outside studied parameters.

Other growth factors in orthopedic use include BMP-7 (OP-1, which was eventually withdrawn from the market), and PDGF (Augment, used in foot and ankle fusion). The pipeline includes next-generation growth factor delivery systems designed to release osteoinductive signals in a more controlled, sustained manner to avoid the bolus-effect complications seen with BMP-2.

Regulatory Framework

The regulatory framework for orthopedic biologics is not uniform, and understanding the different pathways matters for sales professionals.

FDA-approved biologics (like BMP-2/Infuse) went through the Premarket Approval (PMA) process with clinical trials demonstrating safety and efficacy. These products have specific approved indications.

510(k)-cleared products (like many synthetic bone graft substitutes) were cleared based on substantial equivalence to a predicate device. They did not require clinical trials for clearance but must demonstrate equivalent performance to an already-cleared product.

HCT/P products regulated under Section 361 (like many amniotic tissue and allograft products) are regulated as human tissue rather than drugs or devices, provided they meet four criteria: minimal manipulation, homologous use, no combination with drugs or devices, and no systemic effect. These products do not require premarket approval but must be registered with the FDA and comply with tissue banking regulations.

Point-of-care autologous preparations (like PRP and BMAC) are generally not subject to FDA premarket review because the tissue is both harvested and used in the same patient during the same procedure. The centrifugation equipment used to prepare these products is FDA-cleared, but the resulting biologic preparation is not separately regulated as a drug or device.

This patchwork of regulatory pathways creates a market where products with vastly different levels of clinical evidence are used side by side. A growth factor with PMA-level clinical trial data sits on the same shelf as an amniotic tissue product with limited clinical data and a different regulatory classification. Sales professionals need to understand these distinctions to have credible conversations with surgeons and purchasing administrators.

The Clinical Evidence Problem

The biggest challenge facing the orthopedic biologics market is the evidence gap. For many products, the clinical data is insufficient to draw definitive conclusions about efficacy in specific indications.

Several factors contribute to this problem:

• Regulatory pathways don’t require clinical trials for many products. HCT/P-regulated tissue products and 510(k)-cleared synthetic substitutes can reach the market without randomized controlled trials. Once on the market, the commercial incentive to fund expensive trials is limited.
• Product variability. Biologics derived from human tissue are inherently variable. Two lots of DBM from the same manufacturer can have different osteoinductive potential depending on the donor tissue. This variability complicates clinical research and makes it difficult to draw product-specific conclusions from multi-center trials.
• Outcome measurement challenges. How do you measure whether a biologic “worked”? For bone graft substitutes, CT-confirmed fusion is a clear endpoint. But for PRP injected into an osteoarthritic knee, the outcome is symptom relief — which is subjective, variable, and influenced by placebo response.
• Heterogeneous preparation protocols. For autologous products like PRP and BMAC, the preparation technique affects the biological composition. Studies using different centrifugation systems and protocols may produce different results, making comparison across studies difficult.

Surgeons increasingly demand better evidence before adopting new biologic products, particularly at the price points these products command. The days of rapid adoption based on biological rationale and bench data are largely over. Products with strong clinical trial data have a meaningful competitive advantage.

Market Dynamics and What’s Driving Adoption

The global orthopedic biologics market is valued at over $6 billion and growing at approximately 5-7% annually. Several forces are driving adoption:

• Aging population. More degenerative spine and joint conditions mean more procedures that require biological augmentation.
• Shift to outpatient settings. ASC-based procedures benefit from biologics that reduce complication rates and accelerate healing, supporting same-day discharge.
• Surgeon preference evolution. Younger fellowship-trained surgeons are more likely to incorporate biologics into their practice, having been trained during an era when biologic augmentation was standard teaching.
• Patient demand. Patients increasingly research and request “regenerative” treatments, particularly PRP and stem cell therapies, driven by media coverage and direct-to-consumer marketing.
• Manufacturer bundling. Large device companies increasingly bundle biologic products with their hardware offerings, making biologics part of the standard case rather than an add-on.

The competitive dynamics are intense. Major players include Medtronic, DePuy Synthes, Stryker, Zimmer Biomet, NuVasive/Globus, Smith+Nephew, MiMedx, and Integra, alongside dozens of smaller companies focused on specific biologic niches.

What Device Reps Need to Know About Selling Biologics

Selling biologics is different from selling hardware. The product is invisible after it’s applied. You can’t point to an X-ray and show the surgeon your cage or your screw. You’re selling a biological process — and the evidence supporting that process needs to be at your fingertips.

Key principles for device representatives in the biologics space:

• Know the mechanism of action. Can you explain the difference between osteoconduction, osteoinduction, and osteogenesis in a way that’s accurate and clinically relevant? If not, your credibility with surgeons will be limited.
• Know the regulatory classification. Surgeons and administrators will ask whether your product is FDA-approved, 510(k)-cleared, or an HCT/P. The answer affects how they evaluate the product and how they justify the cost.
• Lead with evidence. The strongest selling position in biologics is published clinical data. Peer-reviewed studies, prospective trials, and outcomes registry data carry weight. Bench data and animal studies are supporting evidence, not primary selling tools.
• Understand the economics. Biologics are a significant per-case cost. Be prepared to discuss value in terms of clinical outcomes — fusion rates, complication avoidance, reoperation rates — not just product features.
• Differentiate carefully. The biologics market has a lot of “me too” products. If you’re selling a DBM or amniotic tissue product, you need to articulate what specifically differentiates your product from the competing options, whether that’s formulation, clinical data, processing technique, or cost.

SLR Medical Consulting supplies biologic products to surgical facilities nationwide. To discuss biologics availability or explore distribution opportunities, contact our team.

Frequently Asked Questions

What is the most commonly used biologic in orthopedic surgery?

Demineralized bone matrix (DBM) is the most widely used biologic product in orthopedic surgery by volume. It is used extensively in spinal fusion as a graft extender, combined with local autograft or bone marrow aspirate. DBM provides osteoinductive properties from endogenous growth factors exposed through the demineralization process, and it is available in multiple formulations (putty, gel, strips) that allow surgeons to tailor the product to the specific procedure and anatomy.

Is PRP FDA-approved for orthopedic use?

PRP itself is not FDA-approved as a drug or biologic product. It is an autologous blood product prepared at the point of care using FDA-cleared centrifugation devices. The FDA clears the equipment used to prepare PRP but does not approve the resulting preparation for specific medical indications. This means there are no FDA-approved labeling claims for PRP in orthopedic applications. Surgeons use PRP based on clinical evidence and their own judgment, and insurance coverage varies by indication and payer.

What is the difference between autograft and allograft bone?

Autograft is bone harvested from the patient’s own body, typically from the iliac crest. It provides all three properties needed for bone healing: osteoconduction (scaffold), osteoinduction (growth factors), and osteogenesis (living bone-forming cells). Allograft is cadaveric bone obtained from tissue banks and processed to remove cellular material. Allograft provides osteoconduction and some osteoinduction but lacks living cells (osteogenesis). Autograft has higher fusion rates but requires a second surgical site with associated morbidity. Allograft avoids donor site complications but has lower biological potency.

How are amniotic tissue products regulated by the FDA?

Most amniotic tissue products used in orthopedic surgery are regulated as human cells, tissues, and cellular and tissue-based products (HCT/Ps) under Section 361 of the Public Health Service Act. This pathway requires that the product is minimally manipulated, used homologously (for the same basic function as in the donor), not combined with drugs or devices, and has no systemic effect or dependence on the metabolic activity of living cells for its primary function. Products that meet these criteria are registered with the FDA but do not require premarket approval (PMA) or 510(k) clearance. Products that do not meet all four criteria may be regulated as drugs or devices and would require a more rigorous approval pathway.