The Availability and Pricing of Orthobiologic Knee Injections in the Chicago Metropolitan Area: A Market Assessment Study

Abstract

Background:

Despite mounting clinical evidence for the utility of orthobiologics in nonoperative management of orthopaedic pathology, the market for orthobiologic therapies remains largely unregulated by the Food and Drug Administration, giving rise to a wide range of pricing for these therapeutics by different provider types.

Purpose:

To determine the availability and pricing for platelet-rich plasma (PRP), amniotic or adipose “stem cell,” and bone marrow aspirate concentrate (BMC) injections for the treatment of knee osteoarthritis among orthopaedic sports medicine and alternative providers (eg, chiropractic clinics and stand-alone “regenerative medicine” clinics) in a major metropolitan city.

Study Design:

Cross-sectional study.

Methods:

Orthopaedic sports medicine providers in the Chicagoland area were identified through the American Orthopaedic Society for Sports Medicine (AOSSM) and Arthroscopy Association of North America (AANA) surgeon databases. Alternative clinics offering orthobiologic injections were systematically compiled using Yelp! and Google search listings and reviews. Clinics were contacted using a standardized telephone script. Data were collected for each site on the types of injections offered, whether price was disclosed over the telephone, the price of injections offered, and the source of stem cell injections if they were provided. Mann-Whitney U tests were used to compare the mean price between practices. F tests for equality of variances were used to compare the variability in prices between practice types.

Results:

A total of 25 unique orthopaedic sports medicine practices (comprising 80 AOSSM/AANA surgeons) and 40 alternative clinics offered PRP, stem cell, and/or BMC injections, as indicated over the telephone. There was no difference in likelihood of offering PRP (P = .698) or BMC injections (P = .340). However, alternative clinics were significantly more likely to offer stem cell injections (P < .001). There was no difference in the willingness to disclose the price for PRP (P = .269), stem cell injections (P = .302), and BMC (P = .528) or the source of what each clinic advertised as stem cell injections (P = .630). The mean price for a single PRP injection was significantly higher (P = .011) and significantly more variable (F statistic = .139; P < .001) at alternative clinics. Similarly, the mean price for a single stem cell injection was significantly higher (P < .001) and significantly more variable (F statistic = 0.080; P = .025) at alternative clinics.

Conclusion:

This study demonstrates that orthobiologic knee injections are highly prevalent for in-clinic use within the Chicago metropolitan area, with PRP being the most commonly used therapeutic. When compared with orthopaedic sports medicine providers, alternative clinics were more likely to offer stem cell injections and charge a significantly greater and more variable amount per PRP and stem cell treatment.

Keywords

orthobiologics platelet-rich plasma stem cells bone marrow aspirate concentrate knee osteoarthritis

Orthobiologics have garnered increased attention from patients and providers for their therapeutic potential in a wide array of musculoskeletal conditions.^6,14 Biologic substances, such as platelet-rich plasma (PRP), amniotic/adipose-derived “stem cells,” and bone marrow aspirate concentrate (BMC), have been subject to various direct-to-consumer marketing efforts, and their growing popularity has generated a new potential revenue stream for orthopaedic and medical practices.^4,12,20 Furthermore, there is increasing literature support for biologics standardly indicated, such as with PRP in the management of recalcitrant lateral epicondylitis.²⁶ We utilize the terms “stem cells” and “regenerative medicine” throughout the manuscript, as these terms are utilized and marketed by the clinics offering these therapeutics. However, we do not condone the usage of these terms due to the lack of evidence for amniotic- and adipose-derived therapeutics containing true stem cells, as well as the lack of evidence for any of these therapeutics regenerating cartilage or reversing degenerative changes in the osteoarthritic joint.

The pricing for orthobiologics is of particular clinical relevance given that (1) they are not widely covered by health insurance companies and therefore often confer substantial out-of-pocket charges to patients,¹⁴ and (2) challenges with regulation have led to substantial variability in availability, marketing, and associated charges.⁷ In regard to the former, currently, no major insurance carrier has provided coverage for in-clinic-administered placental-based, adipose-derived, or BMC products. Similarly, PRP is rarely covered, although reimbursement under limited indications is evolving. The Centers for Medicare and Medicaid Services has recently approved PRP coverage for nonhealing wounds, and various other private insurers have introduced limited coverage for orthopaedic indications, such as early knee osteoarthritis (OA) and lateral epicondylitis.²⁶

Previous investigations have surveyed pricing for PRP and stem cell injections offered by orthopaedic sports surgeons in various geographic locations, reporting high pricing and variability.^1,14,23,24 However, no study has assessed the prices charged for BMC injections, which are rapidly increasing in prevalence. Furthermore, there have not been any comparisons of pricing between orthopaedic sports medicine providers and nonsurgical “regenerative medicine” clinics, such as interventional pain, chiropractic, and boutique biologic clinics.^1,14 Such comparisons are made further important by the recent recognition of “rogue stem cell clinics,” which offer biologic therapies with unsupported claims, often at substantial cost and potential risk to patients.¹⁶ Thus, the present investigation is of clinical and scientific interest for multiple reasons. Namely, patient charges—especially when out of pocket—have substantial practical implications for patient access and financial burden of therapy. Additionally, specialties differ in scope of practice as well as ability to evaluate and perform appropriate interventions for various stages of degenerative joint disease (eg, physical therapy, injections, joint preservation surgery, and arthroplasty). The nature of the products, their composition, and mechanism(s) of action are poorly defined, and marketing products as stem cells may not be accurate. Lastly, injections are not without potential side effects, such as iatrogenic infection. Given the poorly regulated nature of existing orthobiologics, there is a risk of inappropriate use for financial gain. For the above reasons, characterization of the availability, nature, and pricing of orthobiologics available to patients is worthy of further investigation.

The purpose of this study was to determine the availability and pricing for PRP, amniotic or adipose stem cell, and BMC injections for knee OA among orthopaedic sports medicine and alternative providers (eg, chiropractic clinics and stand-alone regenerative medicine clinics) in a major metropolitan city. The authors hypothesized that PRP would be the most prevalent orthobiologic knee injection in the area and prices for all injections would be significantly higher at outside clinics given their role(s) as significant revenue streams.

Methods

Identification of Providers

The Chicagoland area was defined as the following counties in northeast Illinois and northwest Indiana: Cook, DuPage, Lake, Will, Kane, McHenry, and Kendall counties in Illinois and Lake and Porter counties in Indiana. Orthopaedic sports medicine providers were identified through the American Orthopaedic Society for Sports Medicine (AOSSM) and Arthroscopy Association of North America (AANA) databases of sports medicine physicians seeing patients in at least 1 location within the listed counties.

Chiropractic clinics and stand-alone regenerative medicine clinics were compiled using a Yelp! search for listings and reviews containing the following keywords: “PRP” or “platelet-rich plasma” or “platelet rich plasma,” “SCT” or “stem cells,” and “BMC” or “bone marrow aspirate concentrate.” Chiropractic and regenerative medicine clinics within the inclusion counties were compiled. A second search was done using the Google Quote Search feature, with the same inclusion terms, to identify clinics that may have had no Yelp! listing or reviews.

Provider Inquiry

A single author (Z.A.K.) individually contacted every clinic up to 3 times by telephone within both the orthopaedic sports medicine providers list and the chiropractic and stand-alone regenerative medicine clinic list, to minimize risk of interobserver bias. A common telephone script was modified from an existing study and used for each telephone call to minimize variation in persuasion.¹ “Hello, I am calling on behalf of my dad, who was looking for local places that offer knee injections for osteoarthritis. Specifically, he was looking for places that offer PRP, stem cell, or BMC injections. Do you all offer any of those services?” If any of the 3 services were offered, a follow-up inquiry was given: “I know these services typically are not covered by insurance, so the cost is the biggest factor for us. Would you be able to provide an estimate for the out-of-pocket cost for [injections offered]?” Additionally, if a site was a provider of stem cell injections, the following question was asked: “I know stem cells can come from various places. Do you know the source of the stem cells and how they are derived?”

This amounted to 3 questions: (1) Do you offer a form of orthobiologic injection? (2) What are the out-of-pocket costs of each injection offered? (3) If offered, what is the source of the stem cell injection. These questions were related to a 1-time injection for 1 knee, rather than a series of injections. Receptionists were asked to transfer the call to an advanced practice provider, such as a physician assistant or nurse practitioner, if they were unaware of treatments.

Data Acquisition

For each site, data were collected on the services offered, whether the price was disclosed by telephone, the price of services if disclosed, and the source of stem cell injections if they were provided. Data collection was completed using Excel (Microsoft Corporation).

Statistical Analysis

All providers were grouped by practice to minimize the risk of large practices skewing data. Divisions of aggregate practices were considered separate practices and were called separately. If prices varied by location within a practice, a mean price was determined by weighting the number of providers at each location. Shapiro-Wilk tests were used to assess for normality within the distributions of prices within a practice type. Mann-Whitney U tests were used to compare the mean price between practice types (ie, orthopaedic sports medicine practices vs chiropractic/regenerative medicine clinics). F tests for equality of variances were used to compare the variability in prices between practice types. All descriptive statistics were completed using Excel. All inferential statistics were completed using R (R Foundation for Statistical Computing).

Results

Identification of Providers

A total of 25 orthopaedic sports medicine practices (comprising 80 AOSSM/AANA surgeons) and 40 alternative clinics offered at least 1 of either PRP, stem cell, and/or BMC injections as an in-clinic procedure for the management of knee osteoarthritis (Table 1).

Table 1

Prevalence and Price of Orthobiologics Within Orthopaedic Sports Medicine and Alternative Clinics^a

	Orthopaedic Sports Medicine Clinics	Alternative Clinics	P
No. identified	25	40
PRP
Offer PRP injections^b	23:2 (92)	35:5 (88)	.698
PRP injection price disclosed^b	23:0 (100)	32:3 (91)	.269
PRP injection price, $	686.00 (172.73)	925.16 (462.99)	.011
Stem cells
Offer stem cell injections^b	5:20 (25)	28:12 (70)	<.001
Stem cell injection price disclosed^b	5:0 (100)	20:8 (71)	.302
Stem cell injection price, $	1451.75 (768.68)	4593.50 (2712.36)	<.001
Stem cell source disclosed^b	4:1 (80)	17:11 (61)	.630
Stem cell source, amniotic/adipose	4:0 (100)	14:3 (82)	>.999
BMC
Offer BMC injections^b	3:22 (12)	10:30 (25)	.340
BMC injection price disclosed^b	3:0 (100)	7:3 (70)	.528
BMC injection price, $	3500.00 (1322.88)	5093.00 (2564.25)	.238

Data are presented as n (%) or mean (SD). Bold P values denote a statistically significant outcome (P < .05). BMC, bone marrow aspirate concentrate; PRP, platelet-rich plasma.

Denotes a dichotomous categorical variable presented as yes/no.

Product Availability

When comparing the availability of in-clinic orthobiologic injections for knee osteoarthritis among orthopaedic sports medicine practices and alternative clinics, there was no difference in the rates of availability for either PRP injections (92% vs 88%; P = .698) or BMC injections (12% vs 25%; P = .340). However, orthopaedic sports medicine practices were significantly less likely than alternative clinics to offer stem cell injections (25% vs 70%; P < .001), irrespective of the source of the product.

Price Transparency

There was no difference between orthopaedic sports medicine providers and alternative clinics in the willingness to disclose the price of PRP (100% vs 91%; P = .269), stem cell injections (100% vs 71%; P = .302), and BMC (100% vs 70%; P = .528), or the source of what each clinic advertised as stem cell injections (80% vs 61%; P = .630) without an appointment (Table 1). These results suggest similar price transparency among differing practice types for patients seeking over-the-telephone pricing estimates for orthobiologic knee injections.

Price Comparison

Among clinics willing to disclose pricing, the mean price of a single PRP injection was significantly higher at alternative clinics compared with orthopaedic clinics ($925 vs $686; P = .011), with significantly more price variability (F statistic = .139; P < .001) at alternative clinics (Figure 1). Similarly, the mean price of a single stem cell injection was significantly higher ($4594 vs $1452; P < .001) with significantly more variability (F statistic = 0.080; P = .025) at alternative clinics (Figure 2). Although the mean price of a single BMC injection was higher among alternative clinics ($5093 vs $3500), this difference did not reach statistical significance (P = .238) (Figure 3). Additionally, there was similar variability in pricing of BMC injections between orthopaedic sports medicine and alternative clinics (F statistic = 4.508; P = .383).

Figure 1.

Box plot showing the price of a single platelet-rich plasma injection by provider type.

Figure 2.

Box plot showing the price of a single stem cell injection by provider type.

Figure 3.

Box plot showing the price of a single bone marrow aspirate concentrate injection by provider type.

Discussion

This study evaluated the prevalence and pricing of orthobiologics available in a high-density urban area and compares differences in orthobiologic offerings between orthopaedic sports medicine practices and alternative regenerative medicine–type clinics. The most important findings from the current study are that orthobiologic knee injections were widely available in the Chicago metropolitan area in both orthopaedic sports medicine and alternative clinic settings, including chiropractic and regenerative medicine practices. PRP and BMC were offered in similar proportions between practice types, but stem cell treatments were more commonly offered in alternative clinics (25% vs 70%; P < .001). Orthopaedic practices offered significantly lower pricing of PRP ($686 vs $925; P = .011) and stem cell injections ($1452 vs $4594; P < .001), with less variability in pricing compared with alternative clinics.

Some form of orthobiologics was offered at the vast majority of practices, with PRP being the most commonly offered agent in both orthopaedic and alternative clinic settings. Importantly, while there was no difference in rates of PRP or BMC availability between practice types, alternative clinics had a significantly higher rate of offering stem cell treatments than orthopaedic sports medicine practices. Most commonly, stem cell products included amniotic-based injections, which are currently classified as category 3 (high risk) products and are discouraged for distribution or use for musculoskeletal applications in injection-based format based on the most recent Food and Drug Administration (FDA) guidance.¹⁷ The prevalence of PRP offering found in this study is significantly higher than the 36% rate found by Alcerro and Lavernia¹ in 2019, when they surveyed orthopaedic surgeons in Miami-Dade County. It is also higher than the 72% rate found by Momaya et al¹⁴ in their 2020 survey of orthopaedic sports medicine practices in the United States. Rates of orthopaedic stem cell offerings found in the present study were similar to those found by Alcerro and Lavernia (25%) and Momaya et al (21.7%); however, the current study found that alternative clinics offered stem cell treatments at much higher rates. BMC rates have not been previously reported, so no comparisons can be made. The greater rates of PRP offering in the current study may reflect a general increase in national PRP prevalence over time.³ This contention is further corroborated by Momaya et al, who reported that 58.6% of Midwest orthopaedic practices offered PRP in 2020, which represents the same geographic region queried in the current study. The greater rate of PRP offering may also be because of the sample, which included a major city, with a high density of tertiary referral centers and large practices.¹⁴ Given the increasing evidence for the efficacy of PRP and BMC,²⁵ it is not surprising that there were no significant differences in rate of offerings between orthopaedic sports medicine practices and alternative regenerative medicine clinics.

Conversely, a significantly higher proportion of alternative clinics offered stem cell treatments than orthopaedic sports medicine practices. There are several considerations given this finding. The high charges associated with stem cell treatments are typically not covered by insurance and are thus paid out of pocket by patients. This issue is compounded by the lack of demonstrated efficacy of stem cell treatments to date.¹¹ Moreover, direct-to-consumer marketing, which is common among alternative clinics, typically extolls the purported benefits of stem cell treatments while minimizing their associated risks.^16,22 Because mesenchymal stem cells are present in such low concentrations, the mechanism by which they elicit any response is unclear; in vitro manipulation and culture expansion^8,18,19,21 are not permitted under current FDA regulations, which ban treatment beyond minimal manipulation and homologous use.^5,17 What benefit such treatments may offer is potentially through a paracrine signaling effect.⁹ Therefore, “stem cell therapy” is an overused and potentially misleading term.¹⁶ Regarding risks, while the overall rate of serious complications (such as neoplasm) appears low,^2,13 infection rates are likely underreported in alternative clinic settings, where there is less established rigorous data collection compared with orthopaedic practices, and alternative clinics are incentivized to underreport adverse effects in order to encourage use.^10,15,22

Pricing for PRP and stem cells was significantly higher for alternative clinics than orthopaedic sports medicine practices. Prices for PRP and stem cells were also significantly more variable in alternative clinics. Differences in pricing and variability between orthopaedic practices and alternative clinics for BMC did not reach statistical significance; however, this is likely because of the smaller sample size, as the mean difference in price was approximately $1500. Orthopaedic sports practice charges for PRP were less than those reported by Alcerro and Lavernia¹ ($897) and similar to those of the Midwest region reported by Momaya et al¹⁴ ($703). Stem cell charges from orthopaedic sports medicine practices were significantly lower in the current study than those reported by Alcerro and Lavernia ($3100) and Momaya et al ($3008). Currently, no major insurance carrier provides coverage for in-clinic-administered stem cell or BMC products. Similarly, PRP is rarely covered, although reimbursement for limited indications, such as lateral epicondylitis and early knee OA, is evolving.²⁶ Therefore, pricing is of paramount concern, as patients largely have to pay out of pocket for the charges for these treatments. Higher charges and greater price variability from alternative clinics may reflect a financial incentive to utilize these products even in the setting of limited clinical supporting evidence. The lower price and reduced variability in treatment pricing among the orthopaedic community are encouraging and suggestive of a prioritization of patient benefits over financial considerations.

Orthobiologics are increasing in prevalence.²⁶ While there are encouraging data regarding their use in symptom management for various forms of knee OA, such treatments are not without risk, and there is a considerable cost to the patient despite unproven efficacy. Alternative medicine clinics may be less conservative in their approach to orthobiologics, making more use of the term “stem cell treatments” and at a higher price.

Limitations

The results of this study must be understood through the context of its limitations. The results were based on the response provided by a single individual who responded to the telephone call at each practice. Although receptionists were asked to transfer the telephone call to an advanced practice provider, such as a physician assistant or nurse practitioner, if they were unaware of treatments, this person may or may not have been a medical provider and may not have been fully knowledgeable about the extent of services provided by a particular practice or clinic. Relatedly, price data were based on the response by the office staff, as opposed to data derived from billing databases. Furthermore, the term “stem cells” is heterogeneous. While it is most used to describe mesenchymal signaling cells, it may be used erroneously to refer to several treatments of other donor tissue products. Finally, the clinical indications for the product and decision-making process were not included as a part of this study.

Conclusion

Our study demonstrated that orthobiologic knee injections are highly prevalent for in-clinic use within the Chicagoland area, with PRP being the most commonly used therapeutic. When compared with orthopaedic sports medicine providers, alternative clinics were more likely to offer stem cell injections and charge a significantly greater and more variable amount per PRP and stem cell treatment.

Footnotes

Presented at the AOSSM Annual Meeting, Washington, DC, July 2023.

Final revision submitted August 13, 2024; accepted August 30, 2024.

One or more of the authors has declared the following potential conflict of interest or source of funding: D.J.K. has received hospitality payments from Arthrex and Stryker, honoraria from Encore Medical, and education payments from Smith & Nephew and Gotham Surgical Solutions & Devices. M.H. has received consulting fees from Vericel; hospitality payments from Arthrex, Stryker, and Orthalign; education payments from Smith & Nephew, Medwest Associates, Foundation Medical, and Arthrex; honoraria from Encore Medical; and a grant from Medical Device Business Services. C.M.B. has received hospitality payments from Stryker, Arthrex, Exactech, and Medical Device Business Services; and education payments from Smith & Nephew. A.B.Y. has received hospitality payments from Stryker; consulting fees from Stryker, JRF Ortho, and Olympus America; nonconsulting fees from Arthrex; education payments from Medwest Associates; and honoraria from JRF Ortho. J.C. has received consulting fees from Smith & Nephew, RTI Surgical, Vericel, Arthrex, DePuy Synthes Products, and Linvatec; nonconsulting fees from Smith & Nephew, Synthes GmbH, Linvatec, and Arthrex; education payments from Arthrex, Medwest Associates, and Smith & Nephew; hospitality payments from Stryker and Medical Device Business Services; and a grant from Arthrex. B.J.C. has received consulting fees from Endo Pharmaceuticals, Aesculap Biologics, Arthrex, Bioventus LLC, DJO LLC, Acumed, Vericel, OSSIO Ltd, and Pacira Pharmaceuticals; nonconsulting fees from Aesculap Biologics, Arthrex, Vericel, Terumo BCT, and Pacira Pharmaceuticals; royalties from Arthrex; hospitality payments from GE Healthcare; and honoraria from Vericel. N.N.V. has received hospitality payments from Abbott Laboratories, Spinal Simplicity, and Relievant Medsystems; royalties from Arthrex, Smith & Nephew, and Graymont Professional Products IP; nonconsulting fees from Arthrex; and consulting fees from Stryker and Arthrex. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Ethical approval was not sought for the present study.

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