Possible causes of pain at the root of the second toe of the left foot include trauma, osteoarthritis, gout, bunion, etc. It is recommended to further consult a doctor to avoid delaying the condition. 1. Trauma: due to excessive exercise or localized pressure, the metatarsophalangeal joints and surrounding tissues may be damaged, resulting in pain, which can be relieved by rest, braking and medication such as ibuprofen. 2. Osteoarthritis: Osteoarthritis may be formed due to degeneration of the interphalangeal joints, and localized pain may occur under the stimulation of the cold environment, which can be treated with medication such as Loxoprofen sodium for pain relief as prescribed by the doctor. 3. Gout: due to the deposition of urate into the local joint tissues, pain can also occur, in addition to the above pain medication, but also the use of febuxostat and other uric acid lowering treatment. 4. Bunion: the big toe will push the second toe to the dorsal side, causing local deformity, and the change of the negative pressure on the sole of the foot can also cause pain, which can be relieved by wearing loose shoes and taking pain relieving medication orally, and surgical treatment can be considered if necessary. It is recommended to go to the hospital in time to avoid delaying the condition.