Aim. Analyzing the vegetative tensity of organism» functional systems before and after surgical treatment of elderly patients with metabolic-and-dystrophic gonarthrosis. Methods. The evaluation of vegetative homeostasis, reactivity of the vegetative nervous system by the data of variation pulsometry («REAN-POLY» RGPA-6/12, Taganrog) in 60 patients with gonarthrosis at the age of 50-72 years and the disease duration — 9+1.5 years before and after surgical treatment: total tunnelization (Group I), tunnelization with osteotomy of leg bones for correction of limb biomechanical axis (Group II), treatment-and-diagnostic arthroscopy (Group III). Results. The reduction of the level of hypoxia tolerance and the decrease of the processes of general adaptation one month after surgery in Group I was registered in 40% of patients. As for patients of Group II, by the end of the period of fixation with the llizarov device — in 50%. As for those of Group III after arthroscopy — in 10% of patients. Among the patients whose 1С / 1С calculated parameter after surgical treatment was registered <1.0, its values were >10.0 before treatment in 70% of cases. At rest, marked vagotonia was registered with hypersympathicotonic reaction to orthotest, as well as with sharp decrease of the proportion of second-order slow waves while transition to standing position (VLF proportion <10.0%), thereby reflecting organism»s energy deficiency state. Conclusion. Preoperative examination. When VLF proportion after orthotest is registered <10.0%, such patients should be referred to risk group and prescribed in-depth examination. The index of centralization (1С) dynamics for orthotest (1С test/1С rest) is one of the criteria of functional recovery level for the particular patient: its increase points to the positive dynamics of restorative rehabilitative process, and the values <1.0 —to the negative one.