Kanamycin concentrations in synovial fluid after intramuscular administration in the horse.

This research paper investigates the levels of the antibiotic kanamycin sulphate in synovial fluid, which lubricates joints, in horses after it has been injected into the muscle. The authors found no significant difference in drug concentration between joints tested at different times after injection.

Research Context and Objective

• The study was conducted to understand the diffusion of kanamycin sulphate, an antibiotic, to various joints in horses after the drug has been intramuscularly injected.
• The main objective was to examine whether there is a difference in drug concentration in the synovial fluid of different joints at different times after the injection.

Methodology

• Six adult ponies were used for the study, and each was given an intramuscular injection at the same site with kanamycin sulphate at 10mg per kg body weight.
• Two hours after the injection, arthrocenteses were performed. This process involves the surgical piercing of joint capsules with a needle to remove synovial fluid, which is found in the cavities of joints, for analysis.
• This was performed on the right metacarpophalangeal, radiocarpal, intercarpal, tibio-tarsal and metatarsophalangeal joints within three minutes.
• Five hours after the injection, the same procedure was carried out on the corresponding joints on the left side of the ponies’ bodies.

Findings

• The researchers did not find a significant difference in the concentration of the drug in the synovial fluid of the joints sampled at 2 and 5 hours after injection.
• The concentration of the drug in the synovial fluid was expressed as a percentage of the drug concentration in the plasma of the ponies.
• The results suggest that the drug is likely to diffuse evenly to the joints within a short period after injection.