Due to an ageing population, the necessity for hip replacement has grown, and therefore, new options are being sought, such as the Fast-track principle, to improve patient condition, reduce their hospital stay and enhance the hospital’s ability to treat more patients. The aim of this study was to investigate the effects of same-day patient mobilisation on pain, side effects, complications, duration of hospital stay, and recovery after primary hip replacement, using intermediate-acting local anaesthetics in spinal anaesthesia (SA). A prospective, randomised study was conducted at the Hospital of Traumatology and Orthopaedics. Forty-six patients undergoing total hip replacement were selected and divided into two groups. Spinal anaesthesia was performed in study group (P) with 70 mg plain prilocaine. The control group (B) received 18 mg heavy bupivacaine in SA. On the first postoperative day, pain during movement was 2.00 (P) and 3.33 (B) on the Numeric Pain Rating Scale, the duration of hospital stay in the study group was shorter by ~1 day, and patient self-care was better in the study group. When the Fast-track principle is used with intermediate-acting SA and early rehabilitation, it is possible to reduce post-operative pain during movement, reduce the length of stay and improve patient self-care abilities.