The diagnosis is "Recurrent internal derangement of the left knee." Following the ICD-9-CM coding guidelines, the index entry for 'Derangement, joint, recurrent, knee' directs to code 718.36. The fifth digit '6' specifies the site as the lower leg, which includes the knee.

The procedure is a "diagnostic arthroscopy of the knee." The ICD-9-CM procedure code index entry for 'Arthroscopy, knee' leads to code 80.26. This code specifically represents a diagnostic arthroscopy of the knee joint. Therefore, the correct combination of codes is 718.36 and 80.26.

A. 715.96 is the code for osteoarthrosis of the lower leg, which is an incorrect diagnosis.

C. 836.2 is for an acute tear of cartilage or meniscus, not a recurrent derangement as stated in the diagnosis.

D. 80.6 is the code for excision of semilunar cartilage, which is a therapeutic surgical procedure, not a diagnostic arthroscopy.

1. National Center for Health Statistics (NCHS). (2011). ICD-9-CM Official Guidelines for Coding and Reporting. U.S. Department of Health and Human Services.

Diagnosis Code: In the ICD-9-CM Tabular List of Diseases

code 718.36 is defined as "Recurrent dislocation of joint; lower leg." The index entry for "Derangement

internal

knee

recurrent" maps to this code.

Procedure Code: In the ICD-9-CM Tabular List of Procedures

code 80.26 is defined as "Arthroscopy of knee."

2. Sayles

N. B.

& Gordon

L. A. (2013). Health Information Management Technology: An Applied Approach (4th ed.). AHIMA Press.

Chapter 10: Diagnostic Coding: This chapter details the process of using the alphabetic index and tabular list to assign ICD-9-CM diagnosis codes. The path for "recurrent derangement of the knee" leads to 718.36.

Chapter 11: Procedure Coding: This chapter explains the use of the ICD-9-CM procedure coding system. The index entry for "Arthroscopy

knee" correctly points to procedure code 80.26.