Page 11 - SMU Spring 2020

As an autologous treatment, platelet alone. A follow-up MRI study show no preparations (AFPs) found no MSCs,
and growth factor concentration can regenerative benefit in the BMAC treated various growth factors and hyaluronan
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be quite variable depending on patient knees. 26,27 Bone marrow can be harvested were present in all AFPs. A multicenter
specific factors and the preparation reliably from various sites in the body prospective RCT comparing amnion
system utilized. PRP preparations can including the posterior and anterior iliac suspension allograft (ASA) to HA and
either be leukocyte rich (LR-PRP) crests, distal femur, proximal tibia, and saline demonstrated lower pain and
or leukocyte poor (LP-PRP). LR-PRP distal humerus; although the posterior improved clinical outcome scores in
(includes white blood cells) is thought iliac crest appears to yield the highest patients treated with a single ASA
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to induce an inflammatory response, concentration of MSCs. 3,19,22 Overall, injection at 6 months follow-up. Further
while LP-PRP (lacking white blood cells) BMAC is more invasive and expensive data is needed to support the use of
is largely considered anti-inflammatory. than PRP with increased harvest amnion in osteoarthritis, but early results
For the treatment of OA, there is high- morbidity. Future work would need to are promising.
level data supporting the efficacy of demonstrate clear superiority in the non-
LP-PRP, particularly in mild to moderate operative treatment of early osteoarthritis Summary and Future Directions
osteoarthritis, while LR-PRP has been to justify expanded utilization. Non-operative interventions are first-line
shown to be more efficacious in the Similar to BMAC, adipose-derived treatments for early knee osteoarthritis.
treatment of tendinopathies. 15,24 While stem cell (ASC) preparations are Patient specific regimens include weight
LP-PRP has good evidence to support its another cell-based therapy aimed at loss, activity modification, core-to-floor
use in the treatment of symptomatic OA, harvesting autologous MSCs. Adipose rehabilitation, and the use of bracing
it is often not covered by insurance plans cells are harvested percutaneously and and/or assist device. Medications and
and therefore can be a prohibitive out- mechanical processing removes lipids biologic injections are utilized as adjuncts
of-pocket expense for the patient despite and disrupts adipose tissue clusters while to reduce pain and inflammation so that
proven efficacy. 18 maintaining the stromal vascular fraction patients may rehabilitate successfully.
Other orthobiologic injection options that is rich in ASCs. ASC therapies focus Short and long acting corticosteroid and
are cellular products often improperly on isolating ASCs from adipose tissue, high molecular weight IA-HA produced
referred to as “stem cell” therapies. These similar to BMAC and amnion. In vitro by bacterial fermentation will likely have
include autologous bone marrow aspirate studies have shown that there are 300 a continued role in the treatment of early
concentrate (BMAC) and adipose-derived times more MSCs in adipose tissue than knee osteoarthritis.
MSCs, and allogeneic amnion injections. in BMAC for the same sample size. The Orthobiologic injections have a growing
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These therapies work by concentrating current literature on ASCs is limited by place in the management of early knee
MSCs within the above FDA limitations of short-term follow-up, limited numbers, osteoarthritis. These injections reduce
minimal manipulation and homologous and inadequate reporting of preparation symptoms but may also modulate the
use. Again, MSCs are not stem cells protocols used and composition of joint environment to promote knee
but are signaling cells that, when formulation. 9,14,23 This is a promising area homeostasis. There is good data to support
activated, respond to their surrounding of future research given the richness the use of LP-PRP for symptomatic early
microenvironment by homing in on a site of MSCs within adipose and relative knee OA. Preliminary data also supports
of injury, secreting regenerative, anti- ease of harvest. Cost concerns and the safety and efficacy of cellular based
inflammatory and immunomodulatory insurance approval are limiting factors products (i.e., autologous BMAC and
factors, and recruiting and stimulating to widespread clinical application in the adipose, allogeneic amnion). Regulatory
the resident stem cells to repair and near future. issues, cost concerns, and insurance
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regenerate the injured tissue. Finally, amniotic-derived treatments approval limit the widespread clinical use
BMAC is harvested from red bone have been used in medicine for the of orthobiologics for early osteoarthritis.
marrow. In addition to MSCs, this treatment of various ailments for over Future high level studies are required.
contains growth factors associated with a century; although research regarding We must establish safe, optimized, and
suppression of inflammatory cytokines, their use in orthopaedics has only standardized preparations so that we
chondrocyte proliferation, and stem cell recently begun. These amnion-derived know exactly what we are injecting into
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migration and differentiation. BMAC products obtained from the placenta our patients. Only in this manner can
7,29
is often used to aid in bone healing and after cesarean delivery are screened, we ensure safety and maximize efficacy.
bony integration, but there is a only a washed, and processed. There are Most importantly, we must all practice
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low level of evidence available to support various processing methods, resulting in evidence-based medicine, advocate for
its primary use in osteoarthritis. A cellular and acellular preparations, both and educate our patients, and remain
recent RCT showed that BMAC is safe of which contain vital proteins, growth fiscally responsible. The future of
and improves pain in knee OA patients, factors, and extracellular matrix. While orthobiologics relies on an ethical and
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but was not superior to saline injection a recent study on several amniotic fluid scientifically rigorous approach.

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