Sudden pain in the foot like a twisted tendon may be related to acute plantar fascia injury, acute lumbar disc herniation, calcium deficiency and other factors. 1. Acute plantar fascia injury: after long-term, extensive sports, plantar fascia strain or strain injury may occur, manifested as a sudden pain in the foot like a twisted tendon phenomenon. 2. Acute lumbar disc herniation: when bending down to carry heavy objects, it may suddenly cause lumbar disc herniation, which presses the nerve root innervating the foot and causes sudden pain in the foot. 3. Calcium deficiency: when there is a lack of calcium in the body, it can cause cramps and spasmodic pain in the hands and feet. Sudden pain in the foot like a twisted tendon should be promptly consulted to clarify the cause of the disease and standardized treatment under the guidance of the doctor to avoid delay.