Radiology Coding Alert

Question: I have a physician’s documentation diagnosing the patient with a sprained thumb. I queried them further for more specificity, and they replied the patient suffered an MCP joint sprain after experiencing a fall while skiing on a recent trip.

Can you please direct me to which code I should use for my claim?

Michigan Subscriber

Answer: Based on the situation you’ve provided, the appropriate diagnosis code in this scenario is S63.649A (Sprain of metacarpophalangeal joint of unspecified thumb, initial encounter). If your documentation or provider specifies laterality, then you’ll choose between S63.641A (Sprain of metacarpophalangeal joint of right thumb, initial encounter) or S63.642A (Sprain of metacarpophalangeal joint of left thumb, initial encounter) for the right or left thumb, respectively.

This injury, also known as skier’s thumb or gamekeeper’s thumb, happens when the tissues supporting the joint where the metacarpal and proximal phalanx meet at the base of the thumb tear or stretch. Patients with the sprain can experience a limited range of motion, stiffness, pain, inflammation, and other symptoms.

Activity code note: If the documentation includes what the patient was doing at the time of the injury, you should include the applicable code. You can locate an activity code in Chapter 20: External Causes of Morbidity (V00-Y99) under the Y93 (Activity codes) code family. In the situation listed above, you’ll use Y93.23 (Activity, snow (alpine) (downhill) skiing, snowboarding, sledding, tobogganing and snow tubing).