In this work the importance of the potentiation and recovery of the balance with a physiotherapeutic intervention that begins in the early preoperative phase is compared with the conventional postoperative rehabilitation. The objective is to evaluate the influence of a muscle enhancement protocol in which a specific work of balance is included, with the physical benefits that this entails for the evolution of the patient. It also seeks to verify if the teaching and recommendation of exercises at home as preparation and conditioning for the intervention of ATR is effective, and to what extent, compared to a guided training in the hospital.

Inclusion Criteria:

• Subjects with severe knee osteoarthritis that have not been operated before of total knee replacement.
• The score in Berg scale must be greater than 21.
• The score of the Mini-Mental State Examination must be equal or greater than 20.
• Once the informed consent is read and explained, patients must accept and agree to participate in the study.

Exclusion Criteria:

• Post-surgical infection of the operated knee.
• Pathology of central origin (i.e. cerebellar) that could interfere with balance or strength
• Vestibular pathology that could interfere with balance