Sprain of unsp collateral ligament of left knee, subs encntr

This code signifies a sprain affecting an unspecified collateral ligament of the left knee, indicating that the specific medial or lateral collateral ligament involved is not documented. This injury typically results from a valgus or varus stress to the knee, causing stretching or tearing of the ligament fibers.

Use this code for follow-up visits, rehabilitation sessions, or subsequent evaluations of a left knee collateral ligament sprain where the specific ligament (MCL or LCL) is not identified in the medical record. This applies when the patient is receiving active treatment for the injury, such as physical therapy or medication management.

• Ensure documentation clearly states "left knee" and "collateral ligament" without further specificity.
• Confirm the encounter is for subsequent care, not the initial injury.
• If the specific collateral ligament (medial or lateral) is documented, use a more precise code from the S83.4 series.