Recurrent dislocation of the patella at the right knee — a non-traumatic, pattern-based diagnosis indicating the kneecap has dislocated multiple times, reflecting underlying patellar instability rather than a single acute event.

Documentation tips

What should appear in the chart to support M22.01.

Source · Editorial brief grounded in 5 cited references ↓

• Explicitly document 'recurrent' or 'history of multiple dislocations' of the right patella — a single dislocation event does not support M22.01.
• Record laterality by name ('right knee') in the assessment or problem list; do not rely solely on operative-side documentation.
• Note the absence of a new acute traumatic mechanism to justify M22 over S83.0-; if trauma is present, document whether this episode is recurrent on top of a prior history.
• Include clinical findings that support patellar instability: positive apprehension sign, J-sign, hypermobility, or prior dislocation episodes with dates if available.
• Document imaging results (MRI, CT, or radiograph) showing trochlear dysplasia, patella alta, elevated TT-TG distance, or MPFL tear to substantiate surgical necessity.
• If conservative care was trialed (bracing, physical therapy), note duration and response before advancing to surgical coding encounters.

Related CPT procedures

Procedure codes commonly billed with M22.01. Linking the right diagnosis to the right procedure is what establishes medical necessity.

Source · CMS LCDs · AAOS specialty guidance · claims-pattern analysis

Common coding pitfalls

The recurring mistakes coders make with M22.01 and adjacent codes.

Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓

• Using M22.01 for a first-time acute traumatic dislocation — that requires S83.0- with a 7th character (A, D, or S), not M22.01.
• Defaulting to M22.00 (unspecified knee) when the operative or clinical note clearly identifies the right side — specificity is required when laterality is documented.
• Confusing recurrent dislocation (M22.01) with recurrent subluxation (M22.11) — subluxation is partial displacement; dislocation is complete. Use the term the provider documents.
• Omitting M22.01 as a secondary diagnosis when coding an S83.0- acute event in a patient with established patellar instability history — the Excludes2 note permits both codes together.
• Coding M22.2X1 (patellofemoral disorder, right knee) instead of M22.01 when the provider documents recurrent dislocation — patellofemoral disorder is a distinct, broader category.

Clinical context

Source · Editorial summary grounded in 5 cited references ↓

Sibling codes

Other billable codes under M22.0 (laterality / anatomic variants).