Tendons are the insertions of the muscles of the forearm into the fingers and pass through the wrist. Their inflammation is called tendinitis. The most affected tendons are the ones going through the hand, wrist and forearm. Treatment is usually conservative, with anti-inflammatory therapy and pain relief, stabilization, and in severe cases when leading to carpal tunnel syndrome, for example, they may need surgery.
The tendons that extend the fingers are the extensors, and the flex, flexor. Both run at a shallow depth, so by accident, they can be sectioned (risk professions: butcher, butchers, cooks, etc). A quick and effective action in these cases is essential to repair the breaks to avoid rigidity later.