An ACL (Anterior Cruciate Ligament) tear is a rupture of a key ligament that stabilizes your knee joint. Before surgery, common symptoms include a loud "pop" at the moment of injury, immediate and significant pain, rapid swelling within hours, a feeling of instability or the knee buckling, and loss of full range of motion. The primary treatment for a complete tear, especially in active individuals, is ACL reconstruction surgery—this is not a simple repair. The surgeon removes the torn ligament and replaces it with a graft, typically taken from your own patellar tendon, hamstring tendon, or a donor's tissue (allograft). Keyhole (arthroscopic) surgery is the standard technique. You should seek an experienced Orthopedic Surgeon who specializes in sports medicine and knee procedures. Look for highly-rated hospitals with dedicated orthopedic or sports medicine departments, such as the Hospital for Special Surgery (HSS) in the US or equivalent major institutions in your region. The cost can vary widely from $20,000 to over $50,000; it's crucial to check with your insurance provider. Post-surgery guidance is critical: you will be in a brace, use crutches for weeks, and must commit to 6-9 months of structured physical therapy to restore strength, mobility, and function before returning to sports.