Tendinopathies
This review is notable that the current body of evidence for amniotic and placental-derived products used in the treatment of musculoskeletal applications is heavily based in in-vitro and animal studies, with little to no human clinical data. The level of evidence reviewed was not adequate for a systematic review or meta-analysis.
Four clinical studies were investigating the effect of amniotic and placental-derived products on tendinopathies.6,8,12,13 Case series were reviewed but omitted from consideration since they lacked sufficient quality to inform the coverage determination. Due to this study design, no causal relationship between the intervention and outcomes can be determined. Additionally, the small heterogeneous patient population severely limits the methodological rigor resulting in significant concerns for systemic bias.13,14 Furthermore, Quinet, et al. had no control arm, and therefore no comparator.14 Huddleston, et al. was excluded from the certainty and risk of bias analysis due to lack of patient outcomes.6 Riboh, et al. was excluded from analysis because there were too few human studies obtained from a non-systematic search.8 Ackley, et al. evaluated the effect of amniotic product on rotator-cuffs12; however, this study was excluded from certainty and risk of bias analysis because it was a case series with no control arm and a relatively small patient population. Based on the evidence reviewed, there is no way to conclude with any degree of certainty that amniotic and placental-derived products have a net positive health outcome in patients with tendinopathies.
Plantar Fasciitis
There were 4 clinical studies investigating the effects of amniotic and placental-derived products on plantar fasciitis. Cazzell, et al. demonstrated improvement in Visual Analogue Scores (VAS) for pain at 3-months, and mean VAS scores were significantly (76%) lower in the amniotic product (dehydrated human amnion/chorion membrane (dHACM)) group when compared to controls (45% lower).15 Though P < 0.0001 is reported, there were no t-statistics, effects sizes, and the confidence intervals for overall effect were not reported. As a result, there is no way to establish whether the treatment was the cause of the observed effect. The mean age for the groups studied was 49 and 53, therefore results reported may not be generalizable to the Medicare population. Zelen, et al. published an industry-sponsored study to investigate the effect of injecting amniotic products at 8 weeks and reported improvement in pain scores, functional health, and well-being in groups receiving amniotic products versus placebo.16 The median pain score from the 0.5 cc micronized dHACM group was 50% that reported by controls at 1 week (P < 0.001), 40% at 4 weeks (P < 0.001), and 25% at 8 weeks (P < 0.001). The median pain score from the 1.25 cc micronized dHACM group was 50% that reported by controls at 1 week (P = 0.002), 20% at 4 weeks (P < 0.001), and 25% at 8 weeks (P < 0.001). No differences were apparent in pain scores between the micronized dHACM groups. In both micronized dHACM groups, significant improvement was observed at study completion for both physical and mental well-being. The study is challenged by small sample sizes, lack of reporting of major comorbidities, and lack of blinding of the investigator creating a risk of bias. There is insufficient evidence to support the use of amniotic and placental-derived injections for plantar fasciitis.
Osteoarthritis (OA) of the Knee
Seven clinical studies investigating the effects of amniotic products on OA of the knee were identified, but there was only 1 RCT and the literature consisted largely of cases series. Farr, et al. published a patient-blinded multicenter randomized controlled comparative trial.11 They investigated the use of amniotic fluid cells and amniotic membrane particulate (amniotic suspension allograft (ASA)) for the treatment of OA of the knee, comparing outcomes with saline (placebo) and HA. They report statistically significant differences between ASA and HA at 3 months, including EQ-5D-5L pain and anxiety subsets; Knee Injury and Osteoarthritis Outcome Score (KOOS) pain, symptoms, and activity of daily living (ADL) subsets; and VAS scores for overall pain, pain during strenuous work, and pain during normal daily living. They conclude the treatment with ASA was superior to HA and placebo. In addition, ASA was significantly better than saline at 3 months in the KOOS symptoms subsets. Though significant conflict of interest (COI) was reported, the multicenter trial design and statistical analysis indicated no discernable response by treatment for the different site groups and no significant difference in patients withdrawn at 3 months. This indicates no significant outcome bias by the investigators with COI. Statistical analysis at 6 months could not be performed due to the significant rate of attrition in the placebo group due to withdrawal because of unacceptable pain. Alden, et al., a retrospective case series, reviewed abstracted data from the medical records of 82 OA patients and 100 knees injected with micronized dHACM.17 An improvement in the KOOS of at least 10 points was considered to represent meaningful positive clinical change. At 3- and 6-months post-injection, 55 and 63% of patients, respectively, reported clinically meaningful improvement in daily living, pain, quality of life, sport/recreation, and symptoms. Castellanos, et al. conducted a non-randomized prospective case series of 20 patients over 24 weeks to evaluate the safety and effectiveness of intra-articular injection of amniotic/umbilical cord (AMUC) particulate in patients presenting with refractory knee OA pain.18 They showed that the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, physical function, stiffness, and global scores improved with a p-value < 0.01. Though they noted this effect was not sustained in obese patients. Another case series by Vines, et al. demonstrated improvement in knee pain.19 Despite a trend towards positive findings, the retrospective study design and significant risk of bias among these studies indicates that there is insufficient evidence to be certain there is a clinical efficacy or long-term safety regarding these products for OA.
Chronic Back Pain
There was only 1 clinical study based on the literature search parameters published to evaluate the effects of amniotic and placental-derived products for back pain. In a case series, Buck, et al. studied 11 patients with discogenic pain, treating them with 50 mg and 100 mg of amniotic membrane and umbilical cord particulate solution.20 Before treatment, all patients reported severe pain, and 10 patients took opioids daily. After treatment, the median reported pain relief was 40%, 50%, and 75% at 1-month (n=6), 3 months (n=8), and 6 months (n=5), respectively. Complete pain relief was noted in 1 patient; however, 2 patients (18%) reported no pain relief at 1 and 3 months. No adverse events, repeated procedures, or complications occurred. There is a high degree of uncertainty regarding the treatment effect due to severe selection bias (6 out of 11 patients were without results reported at 6 months, and only 2 patients had data reported for all time periods studied) and the extremely small sample size.
Due to the high degree of uncertainty, meaningful conclusions regarding the efficacy of amniotic and placental-derived injections for back pain remain elusive.
Trigger Finger
In a single case series, Quinet, et al. hypothesized that amniotic fluid injections could serve as a conservative treatment for trigger finger resulting in pain reduction and triggering frequency in patients with mild (able to be actively extended) to moderate (able to be passively extended) trigger finger.14 Participants were injected with 1 mL amniotic fluid into the sheath of the affected tendon. Before administering the initial amniotic fluid therapy (AFT) injection, baseline triggering frequency, numerical pain rating scale scores (0-10), and Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire scores (1-100) were recorded. The DASH score served as an indication of the patient’s upper-extremity function. Triggering frequency was determined by asking about the frequency of triggering based on the number of times per day or per hour the subject experienced locking or catching. Ninety-six patients (48 men and 48 women, average age 65 ± 11 years) participated in the study. A total of 111 digits received amniotic fluid injections. Pain scores, triggering per day, and DASH scores decreased significantly from baseline to 5 or more months (P < 0.001). There were no episodes of locking or catching reported after injections. While these outcomes may seem promising, the absence of controls and high risk of bias requires further investigation to determine clinical significance.
Systematic Reviews
The literature search parameters generated 6 systematic reviews evaluating amniotic or a combination of amniotic and additional placental-derived products.
Tsikopoulos, et al. performed a meta-analysis on studies examining various injection therapies, including amniotic products for the treatment of plantar fasciitis.21 They found that the dehydrated amniotic membrane had the highest probability of being among the best injection treatments for pain in the short term (0-2 months). This was the data from only 1 RCT performed in the United States (U.S.), which we reviewed.16 Investigators concluded that the dehydrated amniotic membrane was the injection therapy with the highest probability of being superior to placebo injection over 8 weeks; however, additional randomized trials with longer follow-up are necessary to get more precise estimates about the relative efficacy of this intervention.
Riboh, et al. reported that most of the evidence studying these products was heavily biased toward in vitro and animal studies with little to no human clinical data.8 In fact, they determined that the level of evidence obtained from their literature search was inadequate for a systematic review or metanalysis. The authors concluded that little to no research has been done on the effect of amniotic membrane-derived products on intended clinical use and caution against any assumptions regarding the equivalency of the different formulations studied. The most recent systematic review echoed these findings, concluding that clinical trials remain extremely limited, and the current evidence should be interpreted with caution.6
McIntyre, et al. performed a systematic review of both animal and human studies reporting the use of placental-derived therapeutics for musculoskeletal conditions. However, there were only 6 human studies. The studies had a high degree of variability in placental cell types-amniotic and non-amniotic components, placental tissue preparation, routes of administration, and treatment regimens such that no conclusions could be made regarding efficacy.7 Safety, however, they concluded appeared acceptable. However, long-term follow-up data was not available.
Sultan, et al. published 2 systematic reviews, 1 for non-operative applications and another for operative ones.3,22 For non-operative applications, the majority of the reviewed studies (3 of 5) lacked a comparative cohort, resulting in lower confidence in the reported effect size observed by these studies.13,23,24 In addition, the 2 studies that were comparative did not fully compare outcomes to conservative rehabilitation modalities of treatment.16,25 The authors concluded that despite the progress in the field, the applications are in their infancy, and more research is needed to explore their full potential. For operative applications, all studies reviewed were low level of evidence and insufficient to determine the efficacy of amniotic and placental-derived products.
Certainty of Evidence
The best evidence available has serious limitations due to an absence of blinding, control or sham arms, randomization, and allocation concealment methods. Additionally, there are concerns for publication bias, as there are multiple large multicenter trials that were registered to Clinicaltrials.gov but without results posted or published to date. Due to study design, lack of standardization of human amniotic fluid/membrane and placental-derived product injections used (including processing, content, and storage), and small patient population studied to date; there is little certainty that these products have a net positive health outcome in patient populations with similar demographics as Medicare beneficiaries. As a result of ongoing clinical trials, we will continue to monitor the evidence for further developments.
Contractor Advisory Committee (CAC) Evidentiary Review- 5/12/2021
Noridian Healthcare Solutions hosted a multi-jurisdictional CAC meeting to review the evidence on amniotic and placental-based tissue products injections/application for the treatment of musculoskeletal conditions for both non-operative and operative clinical situations. There was a paucity of peer-reviewed literature found on other uses outside of musculoskeletal, burns, wounds, or ophthalmic use, indicating the highly investigational status of such uses. However, those identified references were provided for evidentiary review.
Subject matter experts (SMEs) from hematology/oncology specializing in stem cell transplant, podiatry, orthopedic, physical medicine & rehabilitation, anesthesiology, and rheumatology were represented. All literature submitted by the SMEs to supplement the reference list was also reviewed.
Initial discussion involved the subject of FDA labeling and concerns for erroneous interpretation of FDA regulations surrounding HCT/Ps. SME concerns included the lack of FDA oversight of those amniotic and placental-derived products that have been exempt of pre-market FDA review and approval, as well as the lack of standardization of product content, various processing methods, and paucity of human clinical trials that demonstrated safety and efficacy in general.
The discussions were separated by general conditions or groupings of conditions. These groupings were also based on the actual clinical literature on specific musculoskeletal conditions available for review in which placental/amniotic-based tissue products were utilized as treatment options.
The topics of discussion included:
- General concepts
- FDA labeling/product safety
- OA of the knee, hip, and other joints
- Plantar Fasciitis/Achilles tendinopathies/tendinitis
- Rotator Cuff tears, patellar tendinopathies/tendinitis, lateral epicondylitis, carpal tunnel syndrome, and trigger finger
- Low back pain (including intradiscal and facet joint-related back pain) and cervical facet joint pain
Overall, the panel of SMEs determined that while confidence in short term safety of the discussed musculoskeletal conditions was higher compared to long-term safety, short/intermediate/long-term efficacy, and short/intermediate/long-term post-operative outcomes; all areas were rated low in confidence of the evidence currently available for amniotic and placental-derived injections/applications to treat musculoskeletal conditions.
Rationale for Determination
Due to the paucity of RCTs, poor study designs, small sample sizes, lack of comparators, lack of long-term efficacy and safety data, and high risk of bias in the current body of literature, there is insufficient evidence to demonstrate the efficacy of any amniotic and placental-derived product in the treatment of specific musculoskeletal conditions, whether injected or applied intra-operatively. There is a lack of knowledge of intermediate or long-term safety data derived from human clinical trials.
In addition, based on the available human clinical trials reviewed, there is no consistent formulation, method of delivery, or administration studied to allow for a determination of a standard dosing schedule nor frequency, nor efficacy that can translate across different products. This applies to both non-operative and operative injections/applications used for the treatment of musculoskeletal conditions. For a treatment to be considered medically reasonable and necessary per §1862(a)(1)(A) of the Social Security Act (SSA), the treatment must be appropriate, including duration and frequency furnished in accordance with accepted standards of medical practice for the condition. Therefore, this contractor concludes that the existing evidence and lack of accepted standards of medical practice for amniotic and placental-derived product injections and/or applications do not meet the requirement of medically reasonable and necessary.
Other musculoskeletal conditions that are not referenced in this LCD are due to their lack of acknowledgment in any peer-reviewed literature and are therefore considered investigational and not covered by Medicare.
In conclusion, there is insufficient evidence-based literature to support coverage of amniotic and NON-amniotic placental-derived products injected or applied both non-operatively and intra-operatively to treat musculoskeletal conditions or pain related to said conditions as any other condition that is not burn, wound, or ophthalmologic treatment.
NOTE: In accordance with the CMS Internet-Only Manual, Pub. 100-02, Medicare Benefit Policy Manual, Chapter 16, §140 Dental Services Exclusion, any use of these products for dental conditions is not considered a benefit.