Platelet-Rich Plasma (PRP) injection
If you are post-injury by 7 to 10 days and have a “quiet knee” (minimal swelling), you may be offered a Platelet-Rich Plasma (PRP) injection to enhance your body’s natural healing process. The PRP injection amplifies the natural growth factors your body uses to heal tissue.
This information is not a substitute for advice from your doctor, nor does it contain all the relevant facts. Your doctor will consider your personal circumstances. Please talk with your doctor about any concerns.
Things to consider
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What is Platelet-Rich Plasma (PRP)?
PRP is extracted from your own whole blood. After a small amount (10 to 20 mls) of your blood is taken, it is then put into a centrifuge, which separates the components of your blood. The platelet-rich plasma component is extracted, as the platelets release the “cytokines of healing”, which are used to bathe the injured ACL tissue.
The injection is given by your doctor or you may be referred to a radiologist. Sometimes ultrasound guidance can assist in the placement of PRP.
Because PRP aims to optimise your early inflammatory response of healing, all anti-inflammatory medications (such as ibuprofen, naproxyn, asprin) must be avoided. Indeed for all patients considering to manage their acute ACL injury by adopting the Cross Brace Protocol (CBP) we discourage the use of these medications as they may inhibit the physiology of ACL healing.
What are the advantages and risks of PRP?
PRP injections ulilise your own cellular inflammatory mechamisms to improve musculoskeletal injury. Because PRP is created from your own blood, it is considered a relatively low-risk treatment. Like all intra-articular (joint) injections it carries an extremely low-risk of infection. Your doctor will carry this procedure out using strictly sterile techniques. If you feel any pain at the injection site, apply some ice for up to 20 minutes.
Further studies are required to prove that PRP has the potential to improve or speed healing, however significant improvements in the body’s natural healing process have been observed.
Speak with your doctor about whether this approach is recommended to assist with your ACL healing.
- Kazunori I et al. Intraarticular inflammatory cytokines in acute anterior cruciate ligament injured knee. The Knee. Vol 10, Issue 1, 2003; 93-96
- Kao DS et al. A Systematic Review on the Effect of Common Medications on Platelet Count and Function: Which Medications Should Be Stopped Before Getting a Platelet-Rich Plasma Injection? Orthop J Sports Med. 2022 Apr 12;10(4)