The purpose of determining serum cortisol level is to reflect the activity of stress axis, ethological alterations, acute and chronic pain, life quality, or psychogenic stress. Although it is stated that stress can produce a measurable influence on the cortisol level, a certified value of this pain biomarker in dogs was not generally accepted yet. This study aimed to investigate if serum cortisol measured follows allopathic treatments only, or it is associated with physiotherapy, point out pain level in dogs with orthopedic disease, which could reveal the healing progress. The diagnostic identified: hip dysplasia, cranial cruciate ligament rupture, or intervertebral disc disease. Ortolani and Barden tests, together with clinical examination, drawer sign, and tibia compression test, were done in dogs exhibiting postures, and motion alteration, and X-Ray confirmed. A total of 30 dogs were grouped in healthy (n = 10) and pain groups (n = 20), the blood sampling is done at the beginning of the investigation, and after ten days of the study. Dogs were handled in two ways: G1—treated with Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) only and respectively, G2—by therapy and physiotherapy. The analysis was performed on a Roche Cobas Analyzer (Roche, USA), serum cortisol being determined by Electrochemiluminescence immunoassay (ECLIA), and statistics using ANOVA, following Tukey’s Multiple Comparison Test. The results revealed that, out of ten specimens in the Control group, nine were within the normal limits: 5–65 ng × mL−1 (24.76 ± 19.48678), and one sample under the set limit. In G1, it was observed that the plasmatic P1 values were below the levels of P2, in six situations. In G2, although the status of all subjects improved radically with the removal or evident reduction of pain, confirmed clinically and imagistically, the P2 values in five dogs were higher than the initial P1 values, and in contradiction with the observed clinical reality. Comparing results, the mean difference in G1 was 0.41, and in G2 = 2.54, with an SD for G1 = 13.38, and G2 = 16.66, registering moderate development. Standard deviation illustrated that the values of treated groups were highly spread throughout the interval, and the serum cortisol assay did not generate significant statistical differences between groups in our case. This inferred the doubt whether the used detection method or values registered correctly indicates the pain levels in dog species.

The measurement of pain levels is made differently depending if acute or chronic pain is diagnosed, objective (e.g. cortisol, prolactin, serotonin, catecholamines, or the cardiac frequency and arterial pressure evaluation) or subjective methods being imagined. All subjective methods are including questionnaires and specific additional methods. The aim was the verifying the effectiveness of drug and physiotherapy combinations by using an owner based questionnaire for the chronic patients and a veterinary professional based questionnaire for the acute pain patient group. In this study a total of 20 dogs with observable pain were selected and two groups (n = 10 / group), constituted: G1 - chronic pain, and G2 - acute pain. The treatment of dogs with acute signs of pain was made oral or injectable with NSAIDs administration and for dogs with signs of chronic pain, physiotherapy treatment and drug therapy was administered. The owners of the dogs with chronic pain received the HCPI questionnaire in order to evaluate their dog’s pain level subjectively. For the dogs with acute pain the veterinarian filled out the short form of Glasgow Composite Measure Pain Scale (CMPS-SF). After initiating a Paired t-test in Excel 2010 with the scores obtained with HCPI and CMPS-SF, there was observed a significant reduction of pain after associated drug administration and physiotherapy and no significant evidence of acute pain after drug therapy. The used physiotherapy and drug combinations delivered a significant reduction of chronic pain, both clinically and visually mirrored in score reduction after treatments. The HCPI questionnaire could be considered a valuable tool for evaluating chronic pain in patients in the clinic environment. The CMPS-SF has also proven to be a very useful questionnaire in diagnose of acute pain and evaluation of the effectiveness of drug therapy used.