M23 Internal derangement of knee

⚠ Non-Billable ICD-10-CM 2026
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The ICD-10-CM code for Internal derangement of knee is M23 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Section
M20-M25: Other joint disorders (M20-M25)
Category M23
148 codes (111 billable)
FY2026 Status
Stable since FY2024
Excludes1
Not coded here. These conditions should NOT be coded together with M23.
  • ankylosis (M24.66)
  • deformity of knee (M21.-)
  • osteochondritis dissecans (M93.2)
Excludes2
Not included here. These conditions are coded elsewhere but may be coded together if applicable.
  • current injury - see injury of knee and lower leg (S80-S89)
  • recurrent dislocation or subluxation of joints (M24.4)
  • recurrent dislocation or subluxation of patella (M22.0-M22.1)

Official Coding Guidelines

Osteoporosis without pathological fracture (M81)

Category M81, Osteoporosis without current pathological fracture, is for use for patients with osteoporosis who do not currently have a pathologic fracture due to the osteoporosis, even if they have had a fracture in the past. For patients with a history of osteoporosis fractures, status code Z87.310, Personal history of (healed) osteoporosis fracture, should follow the code from M81.

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.13.d.1
Osteoporosis with current pathological fracture (M80)

Category M80, Osteoporosis with current pathological fracture, is for patients who have a current pathologic fracture at the time of an encounter. The codes under M80 identify the site of the fracture. A code from category M80, not a traumatic fracture code, should be used for any patient with known osteoporosis who suffers a fracture, even if the patient had a minor fall or trauma, if that fall or trauma would not usually break a normal, healthy bone.

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.13.d.2

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Cite This Page

Reference M23 with the canonical source and edition:

M23 — Internal derangement of knee. ICD-10 Coding Pro (ICD-10-CM FY2026). https://icd10codingpro.com/codes/M23

Canonical URL: https://icd10codingpro.com/codes/M23

Related Codes

All Codes in M23

Every most-specific code under M23 Internal derangement of knee (111 codes):

Show the complete M23 code list
M23.000 Cystic meniscus, unspecified lateral meniscus, right knee M23.001 Cystic meniscus, unspecified lateral meniscus, left knee M23.002 Cystic meniscus, unspecified lateral meniscus, unspecified knee M23.003 Cystic meniscus, unspecified medial meniscus, right knee M23.004 Cystic meniscus, unspecified medial meniscus, left knee M23.005 Cystic meniscus, unspecified medial meniscus, unspecified knee M23.006 Cystic meniscus, unspecified meniscus, right knee M23.007 Cystic meniscus, unspecified meniscus, left knee M23.009 Cystic meniscus, unspecified meniscus, unspecified knee M23.011 Cystic meniscus, anterior horn of medial meniscus, right knee M23.012 Cystic meniscus, anterior horn of medial meniscus, left knee M23.019 Cystic meniscus, anterior horn of medial meniscus, unspecified knee M23.021 Cystic meniscus, posterior horn of medial meniscus, right knee M23.022 Cystic meniscus, posterior horn of medial meniscus, left knee M23.029 Cystic meniscus, posterior horn of medial meniscus, unspecified knee M23.031 Cystic meniscus, other medial meniscus, right knee M23.032 Cystic meniscus, other medial meniscus, left knee M23.039 Cystic meniscus, other medial meniscus, unspecified knee M23.041 Cystic meniscus, anterior horn of lateral meniscus, right knee M23.042 Cystic meniscus, anterior horn of lateral meniscus, left knee M23.049 Cystic meniscus, anterior horn of lateral meniscus, unspecified knee M23.051 Cystic meniscus, posterior horn of lateral meniscus, right knee M23.052 Cystic meniscus, posterior horn of lateral meniscus, left knee M23.059 Cystic meniscus, posterior horn of lateral meniscus, unspecified knee M23.061 Cystic meniscus, other lateral meniscus, right knee M23.062 Cystic meniscus, other lateral meniscus, left knee M23.069 Cystic meniscus, other lateral meniscus, unspecified knee M23.200 Derangement of unspecified lateral meniscus due to old tear or injury, right knee M23.201 Derangement of unspecified lateral meniscus due to old tear or injury, left knee M23.202 Derangement of unspecified lateral meniscus due to old tear or injury, unspecified knee M23.203 Derangement of unspecified medial meniscus due to old tear or injury, right knee M23.204 Derangement of unspecified medial meniscus due to old tear or injury, left knee M23.205 Derangement of unspecified medial meniscus due to old tear or injury, unspecified knee M23.206 Derangement of unspecified meniscus due to old tear or injury, right knee M23.207 Derangement of unspecified meniscus due to old tear or injury, left knee M23.209 Derangement of unspecified meniscus due to old tear or injury, unspecified knee M23.211 Derangement of anterior horn of medial meniscus due to old tear or injury, right knee M23.212 Derangement of anterior horn of medial meniscus due to old tear or injury, left knee M23.219 Derangement of anterior horn of medial meniscus due to old tear or injury, unspecified knee M23.221 Derangement of posterior horn of medial meniscus due to old tear or injury, right knee M23.222 Derangement of posterior horn of medial meniscus due to old tear or injury, left knee M23.229 Derangement of posterior horn of medial meniscus due to old tear or injury, unspecified knee M23.231 Derangement of other medial meniscus due to old tear or injury, right knee M23.232 Derangement of other medial meniscus due to old tear or injury, left knee M23.239 Derangement of other medial meniscus due to old tear or injury, unspecified knee M23.241 Derangement of anterior horn of lateral meniscus due to old tear or injury, right knee M23.242 Derangement of anterior horn of lateral meniscus due to old tear or injury, left knee M23.249 Derangement of anterior horn of lateral meniscus due to old tear or injury, unspecified knee M23.251 Derangement of posterior horn of lateral meniscus due to old tear or injury, right knee M23.252 Derangement of posterior horn of lateral meniscus due to old tear or injury, left knee M23.259 Derangement of posterior horn of lateral meniscus due to old tear or injury, unspecified knee M23.261 Derangement of other lateral meniscus due to old tear or injury, right knee M23.262 Derangement of other lateral meniscus due to old tear or injury, left knee M23.269 Derangement of other lateral meniscus due to old tear or injury, unspecified knee M23.300 Other meniscus derangements, unspecified lateral meniscus, right knee M23.301 Other meniscus derangements, unspecified lateral meniscus, left knee M23.302 Other meniscus derangements, unspecified lateral meniscus, unspecified knee M23.303 Other meniscus derangements, unspecified medial meniscus, right knee M23.304 Other meniscus derangements, unspecified medial meniscus, left knee M23.305 Other meniscus derangements, unspecified medial meniscus, unspecified knee M23.306 Other meniscus derangements, unspecified meniscus, right knee M23.307 Other meniscus derangements, unspecified meniscus, left knee M23.309 Other meniscus derangements, unspecified meniscus, unspecified knee M23.311 Other meniscus derangements, anterior horn of medial meniscus, right knee M23.312 Other meniscus derangements, anterior horn of medial meniscus, left knee M23.319 Other meniscus derangements, anterior horn of medial meniscus, unspecified knee M23.321 Other meniscus derangements, posterior horn of medial meniscus, right knee M23.322 Other meniscus derangements, posterior horn of medial meniscus, left knee M23.329 Other meniscus derangements, posterior horn of medial meniscus, unspecified knee M23.331 Other meniscus derangements, other medial meniscus, right knee M23.332 Other meniscus derangements, other medial meniscus, left knee M23.339 Other meniscus derangements, other medial meniscus, unspecified knee M23.341 Other meniscus derangements, anterior horn of lateral meniscus, right knee M23.342 Other meniscus derangements, anterior horn of lateral meniscus, left knee M23.349 Other meniscus derangements, anterior horn of lateral meniscus, unspecified knee M23.351 Other meniscus derangements, posterior horn of lateral meniscus, right knee M23.352 Other meniscus derangements, posterior horn of lateral meniscus, left knee M23.359 Other meniscus derangements, posterior horn of lateral meniscus, unspecified knee M23.361 Other meniscus derangements, other lateral meniscus, right knee M23.362 Other meniscus derangements, other lateral meniscus, left knee M23.369 Other meniscus derangements, other lateral meniscus, unspecified knee M23.40 Loose body in knee, unspecified knee M23.41 Loose body in knee, right knee M23.42 Loose body in knee, left knee M23.50 Chronic instability of knee, unspecified knee M23.51 Chronic instability of knee, right knee M23.52 Chronic instability of knee, left knee M23.601 Other spontaneous disruption of unspecified ligament of right knee M23.602 Other spontaneous disruption of unspecified ligament of left knee M23.609 Other spontaneous disruption of unspecified ligament of unspecified knee M23.611 Other spontaneous disruption of anterior cruciate ligament of right knee M23.612 Other spontaneous disruption of anterior cruciate ligament of left knee M23.619 Other spontaneous disruption of anterior cruciate ligament of unspecified knee M23.621 Other spontaneous disruption of posterior cruciate ligament of right knee M23.622 Other spontaneous disruption of posterior cruciate ligament of left knee M23.629 Other spontaneous disruption of posterior cruciate ligament of unspecified knee M23.631 Other spontaneous disruption of medial collateral ligament of right knee M23.632 Other spontaneous disruption of medial collateral ligament of left knee M23.639 Other spontaneous disruption of medial collateral ligament of unspecified knee M23.641 Other spontaneous disruption of lateral collateral ligament of right knee M23.642 Other spontaneous disruption of lateral collateral ligament of left knee M23.649 Other spontaneous disruption of lateral collateral ligament of unspecified knee M23.671 Other spontaneous disruption of capsular ligament of right knee M23.672 Other spontaneous disruption of capsular ligament of left knee M23.679 Other spontaneous disruption of capsular ligament of unspecified knee M23.8X1 Other internal derangements of right knee M23.8X2 Other internal derangements of left knee M23.8X9 Other internal derangements of unspecified knee M23.90 Unspecified internal derangement of unspecified knee M23.91 Unspecified internal derangement of right knee M23.92 Unspecified internal derangement of left knee
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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