I think I’ve brainstorming stuff this time. The patient was in an accident (traumatic). This is the first time that this malunion of deltoid ligament of the right ankle has been observed. There was no documentation of earlier repair that could’ve resulted in such malunion.

Were it a bone fracture I would code with the ICD-10-CM Code for that fracture with initial encounter (following the concept of delay in treatment and hence the initial encounter code rather than the subsequent encounter malunion code). But in this case surprisingly the physician has stated the term malunion for a ligament.

1. I’m thinking of going with S93.421A. The problem is that the physician has not stated the term sprain explicitly.

2. Also, I was wondering about what the code would be if the ligament was repaired earlier and now presented with malunion? Would we code sprain subsequent encounter then or would we code through complication-postprocedural route? There is no code as such for sprain-ligament-subsequent encounter-malunion.

Am I wrong in extrapolating the fracture malunion concept to ligament malunion diagnosis?

Any thoughts?