Our hands are the tools with which we manipulate our environment. They define us in our occupations, entertain us with our hobbies, and touch the people close to us. With their constant use, our hands are bound to have a variety of cuts, bumps, and bruises. Most of these heal without need for medical attention. However, there are some injuries, initially perceived as minor, which can become severe problems if left untreated:
- Mallet finger: This is a problem when the tip of the finger gets bent suddenly. The tendon that straightens the finger tears off the bone or it may take a small piece of bone with it. At first, the finger may be only slightly bent at the tip, but this often worsens over time. The tendon then shortens and pulls on some additional fibers called the lateral bands. These bands can tighten at the middle joint in the finger and keep it from bending. This is called a swan neck deformity and it can severely limit hand function. Prompt treatment, keeping the fingertip fully straight for several weeks, can prevent developing a swan neck deformity.
- Jersey finger: This is a problem when the grasping hand gets pulled suddenly and the tip of the finger is forcibly extended. Similar to a mallet finger, the flexor tendon ruptures off the bone or may take a fragment of bone with it. This often neglected injury causes little difficulty at first—just loss of bend at the tip of the finger. However, over time, the tendon can scar and contract. Since all 4 fingers share a common muscle, the scarring and shortening can limit motion of the other fingers causing weakened grip. Treated with early surgery and proper post-operative rehabilitation, these fingers can have near normal function.
- Boutonniere deformity: This is a problem that can result from a “jammed” finger or dislocation. The middle knuckle can be injured by an impact to the tip or hyperextension, often involving a ball. Most fingers do well with minimal splinting and early motion. However, if the extensor tendon tears off the middle bone segment, the lateral bands can tighten to bend the middle knuckle and hyperextend the fingertip. This deformity can become very tight so that the finger no longer moves. Early splinting and hand therapy can prevent progressive deformity.
- Nerve injury: A simple cut should not cause numbness for more than a brief period related to swelling and shock to the nerve. Within a couple of days, feeling should return. If numbness is present, particularly if it is the area just past the wound, it should be evaluated. While the numbness may not be bothersome nor limiting, a painful ball of nerve fibers, called a neuroma, can develop. Nerves heal better if repaired early, while the cut is fresh.
A visit to your physician or a hand specialist can determine if an injury requires splinting, therapy, or surgery. If you have concerns, get it checked! It may not be “just a finger.”
Monica S. Wood, MD
Surgery of the Hand and Upper Extremity
Northwest Hand and Orthopedics