Lacerations (Cuts), General Information

Scenario: The typical mountain biker's cut is a caused by blunt "bursting" of the skin during a fall. These cuts usually heal slowly and scar badly if they aren't stitched. Sharp edges on the bike can cut the skin. Situations specific to biking include chain ring bites and fingertip chain-pinch.

Links to "special situation" cuts: Face, mouth, scalp, avulsions and flaps, dog bites.

Description:
A laceration is a tear or cut in the skin. A cut that does not penetrate entirely through the fiber layer (dermis) of the skin is called a "partial thickness" laceration. One that extends down into the fatty layer is called "full thickness."

Concerns:
Any laceration will leave some scar tissue behind. On the face, scars are unsightly. Over joints, a bad scar may prevent full motion. Proper treatment will minimize the scar, making it less noticeable and reducing stiffness. A laceration may damage underlying structures; for example nerves, tendons, or muscle. A laceration may be contaminated with dirt, gravel, or other foreign material. Infection is a risk, especially with deep, crushed, or dirty lacerations. Cuts that occur from human or animal teeth are especially infection-prone.

See the physician if:
   the cut is gaping.
   the edges can be pulled more than 1/8 inch apart with traction on nearby skin.
   the cut is over a knuckle.
   the cut is on the face or genitals
   the cut might be contaminated with foreign material.
   the cut was caused by human or animal teeth.
   there is numbness, deep pain, or inability to move a part fully.

This biker cut himself on the edge of the shifter during an endo. The cut is full thickness (you can see fatty tissue, it's gaping, and it continues to ooze). Being located near a knuckle, the skin will shift with hand motion. This cut will do better if it's stitched.
This biker cut himself on the edge of the shifter during an endo. The cut is full thickness (you can see fatty tissue, it's gaping, and it continues to ooze). Being located near a knuckle, the skin will shift with hand motion. This cut will do better if it's stitched.
Which cuts need stitches?

This cut on the flank is the result of a scraping injury. Note that it's gaping widely. Inside the cut you see fatty tissue. This injury will do better with stitches.

Forward fall, landing with the bottom of the forearm on sharp granite rock. Note the texture in the laceration: this is fatty tissue.
Forward fall, landing with the bottom of the forearm on sharp granite rock. Note the texture in the laceration: this is fatty tissue.
Cut base of thumb, with the skin retracting away spontaneously.
Cut base of thumb, with the skin retracting away spontaneously.
Which cuts need stitches?

This knife-blade cut enters the skin at an angle. You can't see what's inside. Note how the skin on the left side has pulled back and curled up. This cut would be hard to close perfectly without stitches. Yes, you can tape it down and splint the thumb to keep it from wiggling. But if your dressing comes apart, or you get careless, the cut can spring open.
Which cuts need stitches?

This laceration is sharp, short, and tends to remain closed when undisturbed. While most cuts over a knuckle are best checked by your physician, this cut could do well with Steri-Strip closure and splinting of the joint. If you take good care of it after your first-aid treatment, that is.
Cut over a critical knuckle.
Cut over a critical knuckle.
While cutting a patch to size, the knife slipped and hit the left thumb.
While cutting a patch to size, the knife slipped and hit the left thumb.
Which cuts need stitches?

This laceration readily pops open when the nearby skin is touched (see photo below). But it's fairly short, and when left alone, the edges match perfectly. How you'd treat this cut depends on what you'll be doing with your thumb.
If the fingertip can be COMPLETELY protected, this cut could do well without stitches. But you would be taking a bit of a chance. The wound could pop open as you try to use the thumb.

If there's any doubt, see the doctor.

Traction on the skin near a cut lets you see how unstable the skin edges are.
Traction on the skin near a cut lets you see how unstable the skin edges are.
Steri-Strips or a butterfly bandage can secure a closure -- either to help you ride out with a cut that will need stitches, or as permanent treatment for minor, sharp cuts.
Steri-Strips or a butterfly bandage can secure a closure -- either to help you ride out with a cut that will need stitches, or as permanent treatment for minor, sharp cuts.

Immediate care:

Treat a laceration at home only if the skin along the laceration matches up perfectly, and remains together when undisturbed. Clean the wound with the Betadine supplied with your emergency kit. Dry the skin. Tape across the wound with Steri-Strips. Now pad the wound with gauze placed directly over top. If necessary, trim the pad to fit. If the wound is on an extremity, bind the dressing with a kling wrap. Secure the bandage with tape.

This is the same laceration you saw earlier. The wound has been cleaned. Benzoin has been placed and allowed to dry completely. Now a Steri-Strip has been placed.

Steri-Strips don't stretch. But the skin over this knuckle will. The joint must be kept from moving until the early healing is complete. Here a short splint of foam-padded aluminum has been placed and taped. Cuts over moving areas must be secured, so the moving skin doesn't pull the cut back open.
Cuts over moving areas must be secured, so the moving skin doesn't pull the cut back open.
Cuts over moving areas must be secured, so the moving skin doesn't pull the cut back open.

The healing will take about a week. During this time, the Steri-Strip is left in place, until it peels off on its own.

Ongoing care:
Keep the wound clean and dry. Change the bandage daily. Expect about 10-14 days for full healing. You can stop dressing the wound when it appears healed and is non-tender. Avoid bumping the wound area for a few weeks.

Watch for:
See the doctor if there is redness around the wound, red streaks, swelling, drainage, fever, tender bumps in the groin or armpit upsteam from the wound, or an unexplained increase in pain or tenderness.  See section on infection.