Multi-centre retrospective study of the long-term outcome following suspected traumatic elbow luxation in 32 cats

OBJECTIVES

To describe reduction techniques and clinical outcome in a series of traumatic elbow luxations in cats.

MATERIALS AND METHODS

Retrospective review of unilateral elbow luxations treated at five specialist referral centres. Data included signalment, aetiology, concurrent injuries, luxation direction, time to reduction, primary reduction technique, surgical procedure and complications. Cases were excluded if reduction technique was unknown. Telephone owner questionnaire follow-up was completed using a Feline Musculoskeletal Pain Index.

RESULTS

Thirty-two cats were included. Lateral luxations were most common (n = 21). Time (hours) until attempted initial closed reduction was <24 (n = 12), 24-48 (n = 13), >48 (n = 3) or unrecorded (n = 4). Luxation was treated by closed reduction alone (n = 7) or by surgery (n = 25); 14 of 25 cases underwent primary surgical reduction and 11 of 25 were secondary procedures following failure of closed reduction. Transcondylar bone tunnels and circumferential suture (n = 19) was the most commonly used surgical technique. Catastrophic (n = 1), major (n = 11) and minor complications (n = 5) were recorded; reluxation occurred more frequently after closed reduction (n = 8) than after open reduction with fixation (n = 0). Feline Musculoskeletal Pain Index data were available for 12 cats; outcome was good-excellent in all 12, with a median function score of 64.5/68 (range: 55-68) and a median pain score of 0/15 (range: 0-5). Outcome was not associated with reduction technique.

CLINICAL SIGNIFICANCE

Elbow reluxation occurred in 61% of cats following primary closed reduction but did not occur in any open reduction cases. Reluxation rate increased with duration from injury. Most cats had good-excellent owner-assessed outcome, regardless of reduction technique.

Introduction to competition between continuous cultures of Phaeodactylum tricornutum and Dunaliella tertiolecta

When the diatom, Phaeodactylum tricornutum, and the microalga, Dunaliella tertiolecta, are cultured together in a chemostat at dilution factors of approximately 0.5 day-1, the diatom develops the higher population density. At dilution factors above 1.2 day-1 the inability of the diatom to assimilate nutrient as fast as it flows into the chemostat results in the microalga generating the larger population. This change in population densities is accompanied by an increase in the chlorophyll content of the diatom and a decrease in the chlorophyll content of the microalga. Two species of phytoplankton can coexist when they compete for nutrient in a chemostat providing they do not otherwise interact. When the species do interact coexistence in a stable steady state is possible providing intraspecies interactions exceed the interactions between the species. Both species adjust their consumption to minimise the concentration of nutrient in the chemostat and their growth is modified to match the dilution factor of the flow.

Effects of two herbicidal wastewaters on Chlorella sp. and Phaeodactylum tricornutum

The effects on Chlorella sp. and Phaeodactylum tricornutum of two industrial wastewaters known to contain the herbicide residues of Trifluralin and Propanil have been determined by monitoring the number of cells, the chlorophyll fluorescence and the carbon dioxide assimilation simultaneously for a period of 14 days. The growth of the diatom, Phaeodactylum tricornutum, was inhibited by concentrations of herbicidal waste of the order of 0.1-0.5%, apparently because the rate of reproduction was reduced. Chlorella sp. cells, on the other hand, whilst dramatically inhibited by 1% concentrations of herbicidal waste, were able to recover over a period of 14 days. If discharged at concentrations below 0.01%, the industrial wastes appeared not to affect phytoplankton.