Tendon Injuries of the Hand
How Can I Tell If I've Cut a Tendon?
When resting the hand palm-side up on a table, the fingers naturally curl and point toward your torso. If a tendon is completely severed, the finger enervated by that tendon will lie flat in contrast to other fingers, as seen in the picture below.
A tendon can also be partially cut. Partially cut tendons will most likely be asymptomatic—i.e. the fingers may look as though they are not injured—when, in reality, they are. Left untreated, a partially lacerated tendon can lead to a tendon rupture down the road. This is why treatment should be sought immediately after acquiring an acute injury.
If you are suffering from a tendon injury of the hand, seek medical attention immediately.
Tendons Can't Heal Themselves
Though ligaments can sometimes heal on their own and bones are capable of healing without surgical intervention (so long as they are not displaced fractures), tendons cannot. A severed rope has about an equal chance of rejoining its ends when held together as a severed tendon does.
For a severed tendon to heal, it is necessary to surgically intervene soon after the injury is acquired and suture the proximal and distal ends of the tendon.This is because the forearm muscles that control the tendons of the hand will cause a severed tendon to retract internally from the site of the original wound. This doesn't necessarily happen upon injury unless the hand is configured in such a way as to cause this "snap back" effect, or unless the fingers are flexed when the injury occurs.
If left untreated, the tendon usually begins to contract back into the forearm over the course of 3 to 5 days. I've assisted some cases in which we were able to find the tendon up to 7 days after the initial injury; however, waiting too long is likely to result in a tendon graft because a primary repair is no longer possible.
Try to Find a Hand Surgeon
There are surgeons whose specialty involves repairing hand wounds and injuries. My advice is to seek a hand surgeon. Some orthopedic surgeons may perform hand and finger tendon repairs, but their specialty might be bones and not tendons.
Hand surgeons deal with tendons every day and should be considered the experts in the field. Having said that, there may be orthopedic surgeons or even some neurosurgeons who are capable of repairing tendon injuries of the hand.
Complications of hand tendon surgery include postoperative rupture of the repair. This is why instructions from your surgeon and occupational or physical therapist must be followed to the letter.
Do Not Let the Injury Become Worse
Sometimes our feelings outrun pragmatism and safety, and patients begin doing more than they've been advised to do after they start to feel better. Once a tendon is re-injured or once the surgical repair is disrupted, it is not reasonable to expect an optimal outcome on follow-up surgeries. The body is not like wood or stone on which the mason or carpenter can make several errors and still find success; those workers can just start over with new materials. Surgeons do not have that luxury—and neither do you as the patient.
A dear friend of mine once had retinae surgery. She began noticing visual improvement immediately after the operation, to the point that she stopped following the surgeon's instructions. Her lack of adherence to the instructions caused her retinae to detach again, and she is now 80% blind in that eye. How she wishes she had listened to her doctor's instructions! Learn from her example. Follow your surgeon's instructions with great care and rigidity. You'll never regret that you did, but you may regret that you didn't.
Additional Procedure in Case of Tendon Adhesion
Another complication that may occur is tendon adhesion. In the event that the repaired tendon fails to "glide" and allow the finger to flex, a procedure referred to as lysis of adhesions may be necessary. In this procedure, a small incision is made through the original incision line, and small elevating instruments called tenolysis knives are inserted and used to gently separate binding adhesions from the tendon repair.
"After surgery, the wrist is splinted in flexion for approximately 4 weeks. Supervised rehabilitation should begin immediately after surgery. Gentle passive motion can be started early. Careful supervision is necessary during the postoperative period because rupture of repaired tendons is like[ly] to produce a suboptimal result even if recognized and repaired."— Surgery: Scientific Principles and Practice
Common Causes of Tendon Injuries of the Hand
- Box Cutter injuries occur when using X-Acto/utility knives to cut through cardboard boxes or carpet.
- Bagel Cutter injuries occur when using a sharp paring knife to cut through a bagel.
- Saw Blade injuries are particularly troublesome because they tend to not just sever the tendon, but actually remove a chunk of the tendon the size of the width of the saw blade, or the "kerf." Table saws are notorious culprits when it comes to tendon injuries of the hand, so you should be especially careful when operating one.
Tendon injuries tend to be stab-type injuries, which is why the bagel cutter injury is so prevalent. Slash-type injuries can also cut tendons, but are not as common. In my experience, these have been the most common causes of injury; but, as I am sure you can imagine, there are other ways to cut a tendon.
Don't Set Up for an Injury
In the second picture above, we see the perfect setup for a stab injury to the palm, and, quite possibly, a tendon. Frozen meats, especially sausage links, are another common culprit. When trying to wedge a sharp blade between the links, the knife can suddenly give way and end up stabbing the hand.