Which injection is right for your joints?

Hyaluronic acid (HA) injection, often referred to as visco-supplementation, is FDA approved for arthritis of the knee. Due to its success, some physicians have been using it “off-label” (not FDA approved) for the treatment of arthritis in the hip, shoulder, and sacroiliac joints. Once injected the gel-like fluid mimics the synovial fluid that surrounds the joint. This fluid acts as both a lubricant and a shock absorber allowing the bones to move more smoothly against each other.

In time, HA is absorbed into the joint surface where it can stimulate chondrocyte metabolism (the cells that make up cartilage) resulting in a more durable cartilage. A systematic review of 76 randomized controlled trials concluded that injectable hyaluronic acid is an effective treatment for knee osteoarthritis, resulting in beneficial effects on pain, function and patient global assessment.

Platelet rich plasma (PRP) is produced from the patient’s blood, and is concentrated plasma (blood without red blood cells) with many more platelets than what is typically found in circulating blood. The PRP contains many substances which stimulate healing naturally, but in a concentrated form and directly respond to tissue injury in our bodies.  A few of these substances are growth factors such as platelet-derived growth factor, epidermal growth factor, fibroblast growth factor, and connective tissue growth factor, which have been proven to be key blood elements involved in the healing process. Targeted delivery of these growth factors to injured tissues can accelerate and promote the healing cascade within your body naturally. A high-quality PRP system can concentrate platelets 6-10 times greater than what is usually found in blood.

Multiple level 1 studies exist demonstrating efficacy of PRP in the treatment of tendon injuries, and osteoarthritis resulting in increased function, and reduction in pain. Current studies investigating the use of PRP include hair regrowth, dermatologic rejuvenation, and cardiac muscle repair.

How do you decide between injection of hyaluronic acid or platelet rich plasma?

  • PRP has been demonstrated to be equal (non-inferior) and even superior to HA in multiple studies.
  • HA is FDA approved only for use in the knee, and thus is not covered by insurance when used in any other joint.  In many instances, insurers may not pay for knee HA injections despite FDA approval, as this is dependent on individual insurance plans and patient policies.
  • PRP saves patients money. If you chose to use HA for a non-FDA approved indication to treat shoulder or hip osteoarthritis, the injection will cost patients approximately $1500-1800 for the medication. Then, the patient will pay the doctor for the injection, incurring office visit and procedural costs.
  • Although the cost for PRP varies, a high quality PRP injection into a large joint often will range between $1000-2600.
  • The risk of infection, or auto-immune reaction is lower with PRP compared to HA as it comes from the patient’s own blood, and in many cases, contains leukocytes (white blood cells that fight infection).

In conclusion, platelet rich plasma has been demonstrated by multiple high level studies to be as effective or superior to hyaluronic acid injections for knee arthritis. It does not pose a risk for reactive synovitis. The risk of infection or auto-immune reaction is much lower, and there is the potential for significant cost savings to the patient when compared to hyaluronic acid injections.

Sample of studies demonstrating the superiority of platelet rich plasma to hyaluronic injections:

Kanchanatawan W, Arirachakaran A, Chaijenkij K, Prasathaporn N, Boonard M5, Piyapittayanun P, Kongtharvonskul J. Short-term outcomes of platelet-rich plasma injection for treatment of osteoarthritis of the knee. Knee Surg Sports Traumatol Arthrosc. 2015 Sep 19.

Raeissadat SA, Rayegani SM, Hassanabadi H, Fathi M, Ghorbani E, Babaee M, Azma K. Knee Osteoarthritis Injection Choices: Platelet- Rich Plasma (PRP) Versus Hyaluronic Acid (A one-year randomized clinical trial). Clin Med Insights Arthritis Musculoskelet Disord. 2015 Jan 7;8:1-8.

Kon E, Mandelbaum B, Buda R, Filardo G, Delcogliano M, Timoncini A, Fornasari PM, Giannini S, Marcacci M. Arthroscopy. Platelet-rich plasma intra-articular injection versus hyaluronic acid viscosupplementation as treatments for cartilage pathology: from early degeneration to osteoarthritis. 2011 Nov;27(11):1490-501.

Chang KV, Hung CY, Aliwarga F, Wang TG, Han DS, Chen WS. Comparative effectiveness of platelet-rich plasma injections for treating knee joint cartilage degenerative pathology: a systematic review and meta-analysis. Arch Phys Med   Rehabil. 2014 Mar;95(3):562-75

[1] Bellamy N, Campbell J, Robinson V, Gee T, Bourne R, Wells G. Viscosupplementation for the treatment of osteoarthritis of the knee. Cochrane Database Syst Rev. 2006 Apr 19;(2):CD005321