| Platelet rich plasma (or PRP as it is called) is the | | | | vascular endothelial growth factor. |
| "treatment du jour" for many soft tissue injuries | | | | When the PRP is administered to the wound site, |
| since being mentioned as the technique that | | | | it needs to be activated. This is accomplished |
| allowed Hines Ward to play in the Super Bowl. | | | | using a variety of substances. Once activated, the |
| Before stating specifically what PRP is, I will | | | | PRP forms a gel. The framework of the gel is set |
| discuss the rationale behind its use. | | | | up by both platelets as well as fibrin. The gel |
| Wound healing is a complex staged process that | | | | forms a temporary sealant and barrier that allows |
| involves a number of cells. | | | | the initiation of tissue regeneration. |
| The first event during injury is bleeding followed | | | | Growth factors concentrate within the scaffold |
| by tissue regeneration. | | | | and are slowly released over several days. Most |
| There are three distinct stages of tissue | | | | importantly, the gel acts as a structure where |
| regeneration. These include: inflammation, | | | | stem cells can bind. This latter function is |
| proliferation (multiplication) of cells, and tissue | | | | important since stem cells are often used along |
| remodeling. | | | | with PRP. |
| Initially in the laboratory, scientists discovered a | | | | The growth factors from the platelets attract |
| technique to initiate and accelerate tissue | | | | cells to the area to start and accelerate |
| regeneration. They found that an autologous | | | | inflammation. This is called chemotaxis. Stem cells, |
| (from the self) platelet concentrate was filled with | | | | if used, are also attracted (chemoattraction). The |
| growth and healing factors. First used in animal | | | | growth factors from the platelets also stimulate |
| models, this treatment was then used in human | | | | cell multiplication. This is particularly important, |
| subjects with success. | | | | again, if stem cells are used. |
| What was found was that there was a minimal | | | | PRP is best used for soft tissue injuries such as |
| number of platelets required to make this | | | | sprains, strains, tendonitis, and bursitis. |
| technique work. | | | | One critical component to the proper use of PRP |
| While the average platelet count in a normal | | | | is the use of ultrasound needle guidance. If the |
| human being is about 200,000/mm, the amount in | | | | PRP isn't placed in the exact location needed, it |
| a standard platelet concentrate used for PRP is | | | | won't work. The physician administering PRP must |
| about 1,000,000/mm or more. | | | | be well-experienced not only in the science and |
| PRP is collected by drawing a 20-60 cc volume of | | | | biology of this material but must also be a master |
| blood, then concentrating it in a special centrifuge. | | | | of ultrasound needle guidance. |
| The total volume of fluid containing the platelets is | | | | Usually, a tenotomy, meaning making multiple |
| approximately five cc. The platelets within the | | | | holes in the injured tendon or bursa needs to be |
| PRP release growth factors over 7 days. | | | | done prior to introduction of the PRP. |
| Lesser platelet concentrations or platelets that | | | | PRP treatment may have to repeated about 20 |
| aren't viable (living and working) will not enhance | | | | per cent of the time if there is no sign of |
| wound healing. | | | | improvement after 4 weeks. |
| Platelets contain what are called "alpha granules" | | | | One important issue: all anti-inflammatory and |
| that are packed with growth factors. These | | | | immunosuppressive drugs should be avoided prior |
| bioactive growth factors both start as well as | | | | to and for 4 weeks following institution of PRP |
| accelerate tissue repair and regeneration at the | | | | therapy. These drugs may reduce the |
| wound site. These growth factors include: | | | | effectiveness of PRP. |
| adhesion molecules, fibrinogen, interleukin-1 beta, | | | | For more information about PRP or stem cell |
| platelet-derived growth factor, transforming | | | | therapy, call the Arthritis and Osteoporosis Center |
| growth factor-beta, epidermal growth factor, and | | | | of Maryland at (301) 694-5800. |