M22.02 identifies recurrent dislocation of the patella in the left knee — a chronic instability pattern in which the kneecap repeatedly displaces from the trochlear groove, distinct from a single traumatic event.
Verified May 8, 2026 · 4 sources ↓
- Status
- Billable
- Chapter
- 13
- Related CPT
- 7
- Region
- Knee
Documentation tips
What should appear in the chart to support M22.02.
Source · Editorial brief grounded in 4 cited references ↓
- Provider must explicitly document left knee laterality — 'left patella' or 'left knee' in the assessment or HPI supports M22.02 over M22.00.
- Record the number of prior dislocation episodes or reference prior treatment to establish the 'recurrent' qualifier; a single prior event documented in the chart satisfies recurrence.
- Note any imaging findings that support instability: trochlear dysplasia grade, patella alta index, or MPFL tear on MRI — these strengthen medical necessity for surgical intervention.
- Distinguish clearly in the note whether this encounter addresses the chronic instability pattern (M22.02) versus an acute re-dislocation event occurring at this visit, which may also require an S-code for the current episode.
- If conservative care (bracing, PT, taping) has been attempted and failed, document that history — payers frequently require it prior to authorizing MPFL reconstruction or trochleoplasty.
Related CPT procedures
Procedure codes commonly billed with M22.02. 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 M22.02 and adjacent codes.
Source · Editorial brief grounded in CDC ICD-10-CM tabular guidance, AAOS coding references, and cited references ↓
- Using S83.0- instead of M22.02: S83.0- is for acute traumatic dislocations only. If the chart says 'recurrent' or documents prior episodes, the encounter belongs under M22.02 even if the patient presents after another dislocation event.
- Defaulting to M22.00 (unspecified knee) when the note clearly identifies the left knee — always assign the most specific laterality code supported by documentation.
- Confusing recurrent dislocation (M22.02) with recurrent subluxation (M22.12) — subluxation means partial displacement; dislocation means complete displacement. Code what the provider documents, not what you infer from symptom severity.
- Omitting a second code when bilateral recurrent dislocations are documented — M22.02 covers the left side only; add M22.01 for the right if both knees are affected.
Clinical context
Source · Editorial summary grounded in 4 cited references ↓
Use M22.02 when the medical record documents multiple episodes of left patellar dislocation, not an isolated first-time traumatic event. The key differentiator from S83.0- (traumatic dislocation of patella) is chronicity: the provider must have established a pattern of recurrence, typically supported by patient history of prior dislocations, instability complaints, or prior treatment episodes. This is an M-code — it classifies a disorder of the musculoskeletal system, not an acute injury.
M22.02 sits within the M22.0 parent category alongside M22.01 (right knee) and M22.00 (unspecified). If the provider documents bilateral recurrent patellar dislocations, you need two codes: M22.01 and M22.02. Do not use M22.00 when laterality is clearly documented as left — that drops specificity and can trigger payer edits.
Common clinical scenarios for M22.02 include young patients with trochlear dysplasia or medial patellofemoral ligament (MPFL) laxity presenting for surgical stabilization, patients returning for follow-up after a documented prior dislocation episode, and pre-authorization encounters for MPFL reconstruction or lateral release. The diagnosis groups into MS-DRG 562/563 (fracture, sprain, strain, and dislocation) for inpatient encounters.
Sibling codes
Other billable codes under M22.0 (laterality / anatomic variants).
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 4 cited references ↓
01What makes a dislocation 'recurrent' for coding purposes?
02Can I use M22.02 if the patient comes in right after another left patellar dislocation?
03What's the difference between M22.02 and M22.12?
04How do I code bilateral recurrent patellar dislocations?
05Which CPT codes most commonly pair with M22.02?
06Does M22.02 require a 7th character extension?
07Is M22.02 valid for an outpatient office visit when the provider is managing instability non-surgically?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
- 01CDC ICD-10-CM Tabular List 2026 (effective Oct 1, 2025)
- 02icd10data.comhttps://www.icd10data.com/ICD10CM/Codes/M00-M99/M20-M25/M22-/M22.02
- 03aapc.comhttps://www.aapc.com/codes/icd-10-codes/M22.02
- 04outsourcestrategies.comhttps://www.outsourcestrategies.com/blog/patellofemoral-syndrome-coding-and-billing-guidelines/
Mira AI Scribe
Mira's AI scribe captures left-side laterality, the number of prior dislocation episodes, any MPFL injury or trochlear dysplasia noted on imaging, and whether conservative measures have been trialed — all from the provider's dictation. This prevents a drop to unspecified M22.00, blocks acute S-code misassignment, and supports medical necessity documentation for surgical authorization.
See how Mira captures M22.02 documentation