99212. Diagnosis 715.96.
This is an established patient outpatient/office visit and should be coded as 99212. The diagnosis would be 715.96.
The chief complaint was osteoarthritis. The history is problem focused, and the history of present illness has four elements—duration, location, modifying factors, and timing. The review of systems is pertinent to the problem (i.e., right knee), while the past family social history was not addressed. The examination is expanded and problem focused, with five systems being examined (constitutional, cardiovascular, respiratory, gastrointestinal, and musculoskeletal).