Abstract:
Osteoarthritis is a common cause of lameness in horses, resulting in poor performance. Intraarticular
platelet-rich plasma can deliver a collection of bioactive molecules, such as autologous
growth factors and proteins involved in the quality of tissue repair. Horses (n=5) with
osteoarthritis affecting antebrachiocarpal, middle carpal or metacarpophalangeal joints, and
horses (n=5) without osteoarthritis of the corresponding joints (radiographically free of
osteoarthritis), were used for the production of platelet-rich plasma which was subsequently
injected into selected joints. Clinical and synovial fluid changes after intra-articular injection of
platelet-rich plasma as well as synovial platelet-derived growth factor-BB and transforming
growth factor-beta 1 concentration changes were evaluated in these joints and compared
between normal joints and joints with osteoarthritis. A gravity filtration system produced a
moderately concentrated platelet-rich plasma, representing a 4.7-fold increase in baseline
platelet concentration. The synovial effusion score was significantly different between the
control joints and joints with osteoarthritis on Day 0 with a higher score in the group with
osteoarthritis. Within the control group, the synovial effusion score was significantly higher on
Days 1 and 2 compared to Day 0. For both groups, the synovial fluid nucleated cell count,
predominantly intact neutrophils, was significantly increased on Days 1 and 2, with no
significant difference between groups. The mean synovial platelet-derived growth factor-BB
and transforming growth factor-beta 1 concentrations were increased for both groups but
significantly lowered in the group with osteoarthritis on Day 1 compared to normal joints.
Concentrations for platelet-derived growth factor-BB remained unchanged on Day 5, compared
to Day 1, with no significant difference between groups. In conclusion, intra-articular treatment
with platelet-rich plasma resulted in increased synovial growth factor concentrations in joints
but with lower concentrations in joints with osteoarthritis. A transient inflammatory reaction
was seen both clinically as an increase in synovial effusion and cytologically in both normal joints and joints with osteoarthritis.
Description:
The article is based on the thesis of author Yolandi Smit, ‘Clinical signs synovial fluid cytology and growth factor concentrations
after intra-articular use of a platelet-rich product in horses with osteoarthritis’ available at https://repository.up.ac.za/handle/2263/67909
(URI: http://hdl.handle.net/2263/67909).