Answer :
Final answer:
The appropriate ICD-10-CM code for the patient's knee pain would be M17.0, representing primary osteoarthritis of the knee.
Explanation:
The appropriate ICD-10-CM code for the patient's condition would be M17.0, which represents primary osteoarthritis of the knee. This code is used when there is no specified underlying cause or condition causing the arthritis. In this case, the patient's knee pain is attributed to primary degenerative arthritis. Additional codes may be needed to further specify the condition if necessary.