Total Knee Arthroplasty (Postoperative Pain)

The goal of this clinical trial is to learn if the NEUROCUPLE device can reduce pain and opioid use after primary unilateral total knee arthroplasty (TKA) in adults. The main questions it aims to answer are: * Does the NEUROCUPLE device reduce postoperative pain at rest during the first 24 hours after TKA? * Does the NEUROCUPLE device reduce opioid consumption during the first 24 hours after TKA? Researchers will compare the NEUROCUPLE device to a placebo device (identical in appearance but inactive) to see if the device reduces pain and opioid use after surgery. Participants will: * Apply the NEUROCUPLE device or placebo device for 7 days following surgery * Have their pain and opioid use monitored through clinical records and patient reporting * Report pain at rest and during movement on postoperative Days 2 and 7 * Be assessed for nausea, vomiting, device-related side effects, length of hospital stay, and overall satisfaction

The goal of this clinical trial is to compare the effects of femoral triangle block (FTB) and adductor canal block (ACB) on early quadriceps function after total knee arthroplasty (TKA). The main question it aims to answer is whether FTB causes more early quadriceps functional impairment than ACB under a standardized multimodal analgesia protocol. Researchers will compare FTB and ACB using a composite binary functional outcome measured 6 hours after block completion. Quadriceps functional impairment is defined as the inability to perform a structured straight leg raise or quadriceps muscle strength \<50% of the preoperative baseline. Participants will be randomly assigned to receive ultrasound-guided FTB or ACB. All participants will also receive a popliteal plexus block and standardized multimodal analgesia.

Total knee arthroplasty (TKA) is commonly performed to improve mobility and quality of life in patients with degenerative joint diseases. However, severe postoperative pain, limited mobilization, and fluctuations in vital signs negatively affect recovery, particularly within the first 72 hours after surgery. Reiki is a non-invasive complementary therapy aimed at enhancing the body's self-healing capacity through energy transfer. This randomized controlled trial aims to evaluate the effects of Reiki on postoperative pain, mobilization, and vital signs in patients undergoing total knee arthroplasty. Participants will be randomly assigned to either a Reiki intervention group or a control group receiving routine postoperative care. Outcomes will be assessed using validated pain and mobility scales and objective vital sign measurements at the 24th, 48th, and 72nd postoperative hours.