Tendon and ligament injuries are among the most troublesome problems encountered by equine athletes. Healing is slow, taking up to a year or more. And the eventual repaired tendon is rarely as strong as it was before the injury.
Work carried out at the University of Barcelona raises the possibility of treating such injuries with platelet concentrates.
Dr Marta Prades and colleagues in the Department of Animal Medicine and Surgery gained promising results using platelet rich plasma to treat tendon and ligament injuries. In a pilot study, they treated five horses using the technique. Two had recent damage to a forelimb superficial digital flexor tendon (SDFT); three had long-standing proximal suspensory ligament (PSL) desmitis.
The platelet concentrates are prepared by taking blood from the horse to be treated. Whole blood is collected into tubes containing sodium citrate to prevent it clotting. The platelets are separated from the other components of the blood by centrifugation, and are activated before use by adding calcium chloride. Generally 75ml of blood yields about 5ml of platelet concentrate.
The prepared platelet concentrate is injected into the damaged tendon under ultrasound guidance using ultrasound to ensure that it is injected at the correct place. The procedure is repeated three times at two week intervals.
Why use platelets to treat tendon injuries? They supply some of the growth factors that control inflammation and tissue repair. And because the platelets come from the horse to be treated the risk of adverse reaction is minimal.
The two horses with SDFT damage showed improvement both clinically and on ultrasound scan. No improvement was detected in the ultrasound appearance of the PSL desmitis cases, although all three cases improved clinically.
All horses returned to previous level of performance within 6 months. No recurrence of the injury had been reported within 20 months.
Dr Prades emphasises that it is not possible to draw any conclusions about whether the treatment is effective or not. However, the procedure does appear to be safe - no adverse effects were noticed in the five treated horses.
She suggests that injecting autologous platelet concentrates could provide a promising new treatment for damaged tendons and ligaments. She suggests that further investigation into the value of the technique would be worthwhile.
Autologous platelet concentrates as a treatment for musculoskeletal lesions in five horses.
D Arguelles, JU Carmona, F Climent, E Muñoz, M Prades.
Veterinary Record (2008) 162, 208 – 211