Patellar tendon repair is a surgical procedure used to restore knee function after a partial or complete tear of the patellar tendon, which connects the kneecap (patella) to the shinbone (tibia) and allows the quadriceps muscle to straighten the leg. Complete tears are disabling injuries and almost always require surgery, particularly when they result from sudden, forceful movements such as jumping, landing, or direct trauma. Early surgical repair is strongly preferred, as delays can cause the tendon to scar and shorten, making reattachment more difficult and recovery less predictable. Before surgery, patients undergo a clinical evaluation and imaging to confirm the extent of the tear and assess kneecap position. Surgery may be performed as an outpatient procedure or may require an overnight hospital stay depending on individual medical needs. General or regional anesthesia is used. During the operation, an incision is made over the front of the knee to expose the torn tendon. The surgeon reattaches the tendon to the kneecap using strong sutures passed through small drill holes in the patella or by using suture anchors embedded directly into the bone. In cases where the tendon is severely damaged or shortened, additional tissue from the patient or a donor graft may be used to lengthen or reinforce the repair. Some repairs are augmented with protective wires or sutures to support the tendon during healing, which may later require removal. After surgery, the knee is typically immobilized in a brace or immobilizer to protect the repair. Pain is managed with medication and ice, and sutures or staples are usually removed around two weeks postoperatively. Weight-bearing is carefully progressed over time. Initially, patients may be limited to toe-touch weight bearing with crutches, advancing to partial weight bearing by two to four weeks and full weight bearing by four to six weeks, depending on the repair and surgeon guidance. The brace is gradually unlocked to allow increasing knee motion as healing progresses. Physical therapy is a critical part of recovery and begins early, often focusing first on gentle range-of-motion exercises to prevent stiffness while protecting the repair. Strengthening exercises are added gradually, targeting the quadriceps, hamstrings, hips, and lower leg, along with balance and proprioception training. Rehabilitation is highly individualized and depends on tear severity, surgical technique, and patient factors. Most patients require several months of therapy, with full recovery commonly taking six months and sometimes up to a year before strength and function fully return. While outcomes are generally good, potential complications include stiffness, weakness, re-tear, changes in kneecap position, infection, blood clots, or persistent pain. Most patients are able to return to daily activities and work, and athletes may return to sport once strength, endurance, balance, and knee control are restored, typically when the injured leg reaches at least 85–90% of the strength of the uninjured side.