Total hip arthroplasty (THA) is a surgery that relieves hip joint pain and improves its functions and is widely performed in the elderly population. New analgesic methods need to be developed to protect these patients from the pain and side effects of opioids used for treatment. Many scales are available to indicate postoperative patient recovery. One of these is the quality of recovery-15 (QoR-15) recovery test, which was first applied by Stark et al. in 2013. We think that an ESPB applied from the sacral region will spread to the lumbar region by diffusion, affect the lumbar plexus, and provide complete analgesia in the ventral and dorsal regions of the hip by affecting the sacral plexus in the sacral region. The investigator's primary aim in this study is to evaluate the effect of sacral erector spinae plane block (S-ESPB) on the quality of recovery and healing after TKA through the QoR-15 score and to evaluate its effect on postoperative pain.

Total hip arthroplasty (THA) is a surgery that relieves hip joint pain and improves its functions and is widely performed in the elderly population. New analgesic methods need to be developed to protect these patients from the pain and side effects of opioids used for treatment. Many scales are available to indicate postoperative patient recovery. One of these is the quality of recovery-15 (QoR-15) recovery test, which was first applied by Stark et al. in 2013. The investigators think that an ESPB applied from the sacral region will spread to the lumbar region by diffusion, affect the lumbar plexus, and provide complete analgesia in the ventral and dorsal regions of the hip by affecting the sacral plexus in the sacral region. The investigator's primary aim in this study is to evaluate the effect of sacral erector spinae plane block (S-ESPB) on the quality of recovery and healing after TKA, through the QoR-15 score, and to evaluate its effect on postoperative pain.

Anesthesia Technique and Analgesia Protocol a standard to measure postoperative pain severity after THA, and intravenous injection is used as a standard in patients with no contraindications within the scope of the multimodal analgesia protocol. paracetamol 1 gr. 3x1 + Dexketoprofen 50 mg 2x1 and when NRS is 3 and above, 1mg/kg tramadol is administered as a rescue analgesic. In addition, ESPB is applied to patients as a part of multimodal analgesia after THA surgery, unless there are contraindications in the hospitals where the study will be conducted. And 4 mg IV is routinely administered to patients with postoperative nausea and vomiting. Ondansetron is administered . All patients will receive routine monitoring and routine anesthesia management. 20 gauge to patients Intravenous ( IV ) cannulation is provided and 15ml/kg/ h Isotonic fluid will be started. The spinal anesthesia will be applied to the patients by administering 3cc of 0.5% bupivacaine through the L3-L4 or L4-L5 intervertebral space. Patients will then be released to the surgical team for THA surgery. After the surgical procedure is completed, patients will be transferred to the postanesthetic care unit (PACU) for observation. S-ESPB will be applied to patients in Group S

Inclusion Criteria:

• Patients who will undergo unilateral THA
• Spinal anesthesia
• 18-80-year-old patients
• Patients with ASA I-IV
• Patients who will stay in the hospital for at least 24 hours

Exclusion Criteria:

• Patients who do not want to give consent
• Patients under 18 years of age and over 80 years of age
• Patients for whom regional anesthesia is contraindicated
• Patients with confusion
• Patients with ASA V and above
• Patients with abnormal bleeding profile
• Patients using anticoagulants
• Patients with infection in the area to be treated
• Emergency cases