Osteoarthritis (OA) is a progressive joint disease
associated with both mechanical and biologic
abnormalities of the articular cartilage and subchondral
bone. In normal cartilage, a delicate
balance exists between matrix synthesis and
degradation; in OA, however, cartilage degradation
exceeds synthesis. Treatment modalities
include nonpharmacological, pharmacological,
and surgical approaches. Intrarticular platelet
rich plasma (PRP) has emerged as promising
treatment for early stages of knee OA.
PRP is an autologous blood product defined as
a volume of plasma that has a supraphysiologic
platelet count. PRP can accelerate the physiological
recovery process, relieve pain, and contains
anti-inflammatory and anti-bacterial activity.
Although the mechanisms for these complex
interactions are not completely understood, they
are attributed to the more than 30 bioactive proteins
contained in the alpha granules of platelets
including growth factors and proteins, such as
fibrin, fibronectin, vitronectin and thrombospondin.
Several studies now have demonstrated that
intraarticular PRP injections are safe and effective
treatment to reduce pain and improve quality of
life through increased function in knee OA.
The available literature suggests that PRP is a
better option than hyaluronic acid for many knee
OA patients. We identified 12 comparative studies
that demonstrated superiority of PRP as compared
to hyaluronic acid for knee OA. Considering what
is known about the deleterious effects of local anesthetic
and corticosteroids on soft tissue health,
it may be time for a shift in the knee OA treatment
algorithm to favor early intervention for regenerative
therapies including platelet rich plasma.
Key words: Platelet rich plasma, hyaluronic acid,
knee pain, knee osteoarthritis, arthritis, chondrotoxicity
The Role of Platelet Rich Plasma in the Treatment Algorithm of
Knee Osteoarthritis