Revenue Cycle Insider

Question: I have a report with a diagnosis of a traumatic ulnar collateral ligament sprain of the left thumb. When I search for ulnar collateral ligament sprain in the ICD-10-CM code book, I’m directed to the S53.3- subcategory. However, these codes are listed under injuries to the elbow.

What code should I use for this case?

Ohio Subscriber

Answer: You are correct to question the S53.3- (Traumatic rupture of ulnar collateral ligament) code subcategory for the documented injury.

Since the patient experienced a traumatic injury to the digit, you’ll consider the condition an acute or subacute injury. An acute or subacute sprain of the ulnar collateral ligament of the thumb is also known as gamekeeper’s thumb or skier’s thumb. The injury affects the thumb’s metacarpophalangeal joint, so you’ll search the ICD-10-CM Alphabetic Index for Sprain (joint) (ligament) > thumb > metacarpophalangeal (joint).

Turn to the Tabular List to verify the code, where you’ll find that a 6^th character is required to specify laterality and a 7^th character is needed to indicate the encounter type. Assign S63.642A (Sprain of metacarpophalangeal joint of left thumb, initial encounter) to report the documented diagnosis.

Mike Shaughnessy, BA, CPC, Development Editor, AAPC