Autologous blood injection (ABI) is a simple and generally beneficial procedure for the treatment of chronic tendinopathy.
Tendinopathy is a significant cause of musculoskeletal presentation to both general practitioners and specialists alike and may take up to 12-18 months to settle down. Tendinopathy is generally a self-limiting degenerative process and the prognosis should be considered favourable. However a small sub-set of patients will fail to improve. This may be despite conventional treatment including anti-inflammatory medications, cortisone injections and eccentric rehabilitation programs
It has been postulated that injections of blood products – either autologous whole blood, or PRPP (platelet rich plasma protein) – may be helpful in stimulating tendon regeneration. The theoretical use of blood product injections relates to platelet derived growth factors (PDGF’s) that are carried in the platlets in whole blood. Areas of tendinopathy are characterised by poor blood supply which may contribute to their slow healing. Injecting fresh blood around tendons may introduce growth factors to the area, which may stimulate a healing response. The landmark paper supporting ABI was written by Edwards of the effects on tennis elbow (1). 26 of 28 patients in this study improved after a series of up to 3 injections. Other studies have also shown benefits in other tendon conditions including golfers elbow and patella tendonosis. Thus ABI gives us a treatment option between physio and anti-inflammatory treatment and surgery
ABI is relatively simple procedure to perform. It involves taking a small quantity of venous blood and re-injecting it around the affected tendon. It can be performed on the day of consultation and does not require imaging guidance. A PRPP injection requires 30 mls of blood which must be centrifuged for 15 minutes. It requires more time and expense and there are limited studies showing any benefit over ABI in the treatment of tendinopathy.
The main side effect from these injections is pain at the site of the injection and bruising. The severity and duration of this varies from person to person, but may be anywhere up to 1-2 weeks. This is best treated with ice and simple analgesics. Maintenance exercises may be performed as soon as the local pain settles, and should be encouraged. The recovery time for these injections may be anywhere between 1-6 weeks. They may need to be repeated up to 3 times, generally at 6 week intervals, depending on the level of improvement.
In summary a reasonable paradigm for the treatment of tendinopathy may include:
- Initial physiotherapy with an exercise component (generally an eccentric program)
- If pain persists or is interfering with rehabilitation exercises or daily activities then consider 2-3 corticosteroid injections at 4-6 weekly intervals with continuation of rehab exercises
- If pain is recurring or there is limited improvement with this approach then consider second line treatment with a blood product injection.
- ABI is suggested initially as it is a cheaper alternative and more readily administered. The literature would suggest similar levels of efficacy and nothing to suggest that PRPP injections have advantages over and above autologous blood injections.
- If autologous blood unhelpful (up to 3 injections), then consider a trial of PRPP injection.
- Surgery as a last option if persistent pain greater than 12 months and interfering with work/daily activities and all other treatment options exhausted.
- Edwards SG, Calandruccio JH. Autologous blood injections for refractory lateral epicondylitis. J Hand Surg [Am]. Mar 2003;28(2):272-8.