Mallet finger is a separation of the extensor tendon at the most distal joint of the finger, the distal interphalangeal (DIP) joint. It gives the end of the finger the typical mallet shape as the DIP joint droops down and you are unable to actively straighten it.

Jarred finger is a description of the mechanism, typically a force directed longitudinally along a straight finger. A ball to the end of the finger is the most common.

There are 27 bones in the hand. Some fracture (same as a break) more commonly. Treatment depends on whether it is: open or closed, displaced or undisplaced, stable or unstable.

A dislocation is when the bones of a joint are forced out of their normal position and the joint surfaces are no longer touching. Subluxation is similar, but the joint surfaces still overlap. Treatment depends on whether it is: open or closed, stable or unstable.

Ligaments are supportive structures between bones. They support, stabilise and limit movement of joints. Treatment depends on whether the joint is: open or closed, stable or unstable.

Important structures of the hand, including; joints, tendons, arteries and nerves, are very close to the surface. Knives, glass and porcelain frequently cut all the way down to bone despite a very small skin wound. Surgery is recommended if there’s any risk of an injury to one of these structures.

Tendons connect muscle and bone. Most of the muscles for the hand are in the forearm, with the tendons passing the wrist and attaching at various point in the fingers and thumb, making them move. Treatment depends on whether the injury is open or closed and its location. To get optimal results recovery should be closely supervised with a hand therapist.

Nerves carry sensory information from the skin back to the spinal cord and brain to give us the sense of touch. This is particularly important in the hand. Nerves also control muscle function. The nerves to the intrinsic muscles of the hand are deep and injuries are relatively rare, but if missed the reduced function can be significant.

Injuries to the nail are usually caused by a crush or cut. After a crush an x-ray should be done to exclude a fracture. Nail bed injuries are repaired to prevent future nail plate deformity. This is not just a cosmetic concern as function can be affected if the nail gets caught on clothing or during activities.

Infection can develop after any injury where the skin is breached. For this reason, wounds are often debrided, washed out and repaired in the operating room. This is particularly true for contaminated wounds caused by bites, oyster shells or dirty tools.