Intra-articular temperature: technique and reliability in an animal model

To determine if reproducible and reliable measurements of intra-articular temperature could be performed in an animal model, surface and intra-articular measurements were studied in 30 rabbits. Anterior insertion of a thermometer probe into the joint cavity was found to be a reliable method for measuring intra-articular temperature in the rabbit knee. This method yielded temperatures with less than 0.1C variation in contralateral and serial determinations. Consistent differences in intra-articular temperatures were observed between normal knees and contralateral knees in which arthritis had been experimentally induced. Measurements of surface temperature and knee intra-articular temperature by a posterior approach, however, did not give consistent or reproducible values.