What are autologous blood injections?
Autologous blood injections (ABI) are simply injections of the patient’s own blood into the area of chronic tendon injury.
What is the evidence?
Autologous Blood Injection (ABI) has recently been described for the treatment of tennis elbow. Several recent medical studies have demonstrated its effectiveness for tennis elbow and also for the treatment of other tendon problems such as plantar fasciitis and golfer’s elbow. It is assumed that ABI works by introducing certain “growth factors” present in the blood to the area of injury. These growth factors act as mediators which promote healing. The mechanism of short term relief following steroid injection or needling is not properly understood, and it may in fact be that trauma to the area of tendon injury with the needle may similarly promote healing within the tendon.
Using ultrasound scanning, it has been seen that following autologous blood injection there is a reduction in tendon thickness and inflammatory changes seen with the tendon. There is also a partial resolution of tendon tears following injection.
How are autologous blood injections done?
A small amount of blood is withdrawn from a vein, and then simply injected around the injured tendon.
We routinely perform one injection initially and there may occasionally be a requirement for a second injection four weeks later. If it is going to help, most pain relief occurs within the first 6 weeks. Patient selection and an accurate diagnosis is critical to the success of the procedure.
Recent studies suggest that autologous blood injections may have a more permanent effect on long-term benefit than that achieved with steroid injections. This is probably related to the healing benefits of ABI causing the tendon to return to its pre-injury state rather than simply relying on the anti-inflammatory action of steroid injections.