How long it takes for a patella fracture to bend depends largely on the treatment plan, most in about 3 months. If the treatment is conservative, with fixation in a cast or brace, the fracture will heal before it can be gradually bent and moved, which usually takes about 4-6 weeks. The joint becomes stiff at the beginning and it may take 2-3 months to restore the function of the joint. In some cases, the joint becomes permanently stiff due to the lack of functional activity in the early stage, which requires another surgery to release the joint. If surgical treatment is taken, that is, incision and internal fixation, the fractured patella is already strongly fixed internally during surgery, so the knee can be bent in bed on the first day after surgery without causing joint stiffness, and after the fracture heals, the patient can gradually get out of bed and walk with weight, and the joint function will recover better than conservative treatment. For patients treated conservatively, premature bending should be avoided as it may affect the healing of the fracture and even lead to fracture displacement and deformed healing.