Evaluation and Treatment Flowchart for Skier's Thumb
You may have seen a flowchart meant to help someone make an important or difficult decision. Physicians use this same idea when examining patients and determining the best treatment approach. For example, they might think "if this symptom is present, then I will order this test -- or if the patient reports this is how he or she got hurt, then my treatment will be XYZ." That type of decision-making process is referred to as a flowchart or algorithm.

In this review article, hand surgeons from Mayo Clinic in Rochester, Minnesota report on an algorithm they use to evaluate and treat skier's thumb (also known as gamekeeper's thumb). The names skier's thumb and gamekeeper's thumb refer to the same injury: tear or rupture of the ulnar collateral ligament (UCL) of the thumb.

In the case of skier's thumb (obviously the result of a skiing accident), the UCL is damaged when a sudden force is placed on the thumb. Usually this occurs when the hand is wrapped around a ski pole and the pole comes to a sudden stop but the skier does not.

With gamekeeper's thumb, a repetitive force is placed on the thumb over and over again. This name was actually applied many years ago when Scottish gamekeeper's killed wounded rabbits and other small game by breaking their necks. The repetitive force against the web space between the thumb and index finger eventually damaged the UCL.

The evaluation and treatment algorithm presented here starts with a suspected UCL injury. The next step is a physical exam and X-rays. The X-rays may show some obvious damage such as joint laxity (looseness) or bone fracture. That result would require different follow-up than if the X-rays are suspicious but not clear. Unclear or “equivocal” findings require further testing such as stress X-rays, ultrasound, or MRIs.

Once the surgeon is able to make an accurate diagnosis, then the algorithm can be used again to determine the best treatment for each patient. For example, a complete rupture of the ulnar collateral ligament would mean surgery to repair the damage.

An incomplete rupture could possibly be treated with a splint on the thumb and hand. Such a splint would immobilize the joint for six weeks. Following treatment of any sort, hand therapy to rehabilitate the thumb would be the last step. Once motion, strength, and function were returned, the patient would be discharged from further treatment.

Of course, in many cases, the algorithm isn't really that simple. There are different approaches to take when performing the surgical repair or reconstruction. Which way to go depends in part on how old the injury is. Acute (early) injuries will be surgically repaired differently than chronic (old) injuries.

Sometimes acute injuries treated conservatively (without surgery) can become chronic problems. Later those chronic problems require surgery and that's another decision tree (algorithm). Whenever possible (for acute and chronic injuries), the surgeon tries to perform a primary anatomic repair (i.e., put the ligament back where it belongs. That isn't always possible, especially if the ligament ruptured and snapped way back away from the bone where it attached. Over time, the torn soft tissue tightens up so it can't be pulled back to its insertion site on the bone.

More complex ligamentous procedures involve tendon transfers or tendon grafts to actually reconstruct the torn ligament. This more involved surgery may be the only way to regain strength and stability of the joint. The goals of any surgery for UCL rupture are to reduce pain, improve motion, and restore function.

Living with a thumb that can't pinch with enough strength to pick up objects isn't a life or death situation but it does result in some potentially disabling problems. The final decision for someone who has had reconstructive surgery is what to do if it fails. This is usually a case of someone with a chronically painful thumb. It either repeatedly dislocates, is too weak to pick up even small objects or touch the tip of the little finger, or have severe arthritic changes in the joint.

What does the decision tree suggest for this person? Thumb joint replacements are not possible so joint fusion (called arthrodesis) may be the only and final option. Another algorithm pops up now as the surgeon decides whether to fuse the joint using Kirschner wires, tension-band wiring, and/or bone grafting.

Algorithms go full circle in that the treatment choices are based on results of past treatment approaches. Good results using one method over another create changes in the flowchart. Optimal outcomes usually occur when a proper diagnosis is made and treatment is provided early on (before additional problems develop or the condition becomes chronic).
Peter C. Rhee, DO, et al. Management of Thumb Metacarpophalangeal Ulnar Collateral Ligament Injuries. In The Journal of Bone and Joint Surgery. November 7, 2012. Vol. 94A. No. 21. Pp. 2005-2012.