DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Category · FY2027

M23 Internal derangement of knee

  • Header · not billable

M23 is not billable. The category heads 111 billable codes in FY2027, grouped under 8 subdivisions.

Index → code

Where it sits

  1. Chapter 13 Diseases of the musculoskeletal system and connective tissue (M00-M99)
  2. M20-M25 Other joint disorders (M20-M25)
  3. M23 Internal derangement of knee
Billable codes
111
Subdivisions
8
CC / MCC codes
0 / 0
HCC V28 codes
0
New FY2027
0
Index entries
52

Codes in M23

  1. M23.0
    Cystic meniscus
    Header
  2. M23.00
    Cystic meniscus, unspecified meniscus
    Header
    Inclusion terms 2

    Inclusion terms

    • Cystic meniscus, unspecified lateral meniscus
    • Cystic meniscus, unspecified medial meniscus
  3. M23.000
    Cystic meniscus, unspecified lateral meniscus, right knee
    Billable
  4. M23.001
    Cystic meniscus, unspecified lateral meniscus, left knee
    Billable
  5. M23.002
    Cystic meniscus, unspecified lateral meniscus, unspecified knee
    Billable
  6. M23.003
    Cystic meniscus, unspecified medial meniscus, right knee
    Billable
  7. M23.004
    Cystic meniscus, unspecified medial meniscus, left knee
    Billable
  8. M23.005
    Cystic meniscus, unspecified medial meniscus, unspecified knee
    Billable
  9. M23.006
    Cystic meniscus, unspecified meniscus, right knee
    Billable
  10. M23.007
    Cystic meniscus, unspecified meniscus, left knee
    Billable
  11. M23.009
    Cystic meniscus, unspecified meniscus, unspecified knee
    Billable
  12. M23.01
    Cystic meniscus, anterior horn of medial meniscus
    Header
  13. M23.011
    Cystic meniscus, anterior horn of medial meniscus, right knee
    Billable
  14. M23.012
    Cystic meniscus, anterior horn of medial meniscus, left knee
    Billable
  15. M23.019
    Cystic meniscus, anterior horn of medial meniscus, unspecified knee
    Billable
  16. M23.02
    Cystic meniscus, posterior horn of medial meniscus
    Header
  17. M23.021
    Cystic meniscus, posterior horn of medial meniscus, right knee
    Billable
  18. M23.022
    Cystic meniscus, posterior horn of medial meniscus, left knee
    Billable
  19. M23.029
    Cystic meniscus, posterior horn of medial meniscus, unspecified knee
    Billable
  20. M23.03
    Cystic meniscus, other medial meniscus
    Header
  21. M23.031
    Cystic meniscus, other medial meniscus, right knee
    Billable
  22. M23.032
    Cystic meniscus, other medial meniscus, left knee
    Billable
  23. M23.039
    Cystic meniscus, other medial meniscus, unspecified knee
    Billable
  24. M23.04
    Cystic meniscus, anterior horn of lateral meniscus
    Header
  25. M23.041
    Cystic meniscus, anterior horn of lateral meniscus, right knee
    Billable
  26. M23.042
    Cystic meniscus, anterior horn of lateral meniscus, left knee
    Billable
  27. M23.049
    Cystic meniscus, anterior horn of lateral meniscus, unspecified knee
    Billable
  28. M23.05
    Cystic meniscus, posterior horn of lateral meniscus
    Header
  29. M23.051
    Cystic meniscus, posterior horn of lateral meniscus, right knee
    Billable
  30. M23.052
    Cystic meniscus, posterior horn of lateral meniscus, left knee
    Billable
  31. M23.059
    Cystic meniscus, posterior horn of lateral meniscus, unspecified knee
    Billable
  32. M23.06
    Cystic meniscus, other lateral meniscus
    Header
  33. M23.061
    Cystic meniscus, other lateral meniscus, right knee
    Billable
  34. M23.062
    Cystic meniscus, other lateral meniscus, left knee
    Billable
  35. M23.069
    Cystic meniscus, other lateral meniscus, unspecified knee
    Billable
  36. M23.2
    Derangement of meniscus due to old tear or injury
    Header
    Inclusion terms 1

    Inclusion terms

    • Old bucket-handle tear
  37. M23.20
    Derangement of unspecified meniscus due to old tear or injury
    Header
    Inclusion terms 2

    Inclusion terms

    • Derangement of unspecified lateral meniscus due to old tear or injury
    • Derangement of unspecified medial meniscus due to old tear or injury
  38. M23.200
    Derangement of unspecified lateral meniscus due to old tear or injury, right knee
    Billable
  39. M23.201
    Derangement of unspecified lateral meniscus due to old tear or injury, left knee
    Billable
  40. M23.202
    Derangement of unspecified lateral meniscus due to old tear or injury, unspecified knee
    Billable
  41. M23.203
    Derangement of unspecified medial meniscus due to old tear or injury, right knee
    Billable
  42. M23.204
    Derangement of unspecified medial meniscus due to old tear or injury, left knee
    Billable
  43. M23.205
    Derangement of unspecified medial meniscus due to old tear or injury, unspecified knee
    Billable
  44. M23.206
    Derangement of unspecified meniscus due to old tear or injury, right knee
    Billable
  45. M23.207
    Derangement of unspecified meniscus due to old tear or injury, left knee
    Billable
  46. M23.209
    Derangement of unspecified meniscus due to old tear or injury, unspecified knee
    Billable
  47. M23.21
    Derangement of anterior horn of medial meniscus due to old tear or injury
    Header
  48. M23.211
    Derangement of anterior horn of medial meniscus due to old tear or injury, right knee
    Billable
  49. M23.212
    Derangement of anterior horn of medial meniscus due to old tear or injury, left knee
    Billable
  50. M23.219
    Derangement of anterior horn of medial meniscus due to old tear or injury, unspecified knee
    Billable
  51. M23.22
    Derangement of posterior horn of medial meniscus due to old tear or injury
    Header
  52. M23.221
    Derangement of posterior horn of medial meniscus due to old tear or injury, right knee
    Billable
  53. M23.222
    Derangement of posterior horn of medial meniscus due to old tear or injury, left knee
    Billable
  54. M23.229
    Derangement of posterior horn of medial meniscus due to old tear or injury, unspecified knee
    Billable
  55. M23.23
    Derangement of other medial meniscus due to old tear or injury
    Header
  56. M23.231
    Derangement of other medial meniscus due to old tear or injury, right knee
    Billable
  57. M23.232
    Derangement of other medial meniscus due to old tear or injury, left knee
    Billable
  58. M23.239
    Derangement of other medial meniscus due to old tear or injury, unspecified knee
    Billable
  59. M23.24
    Derangement of anterior horn of lateral meniscus due to old tear or injury
    Header
  60. M23.241
    Derangement of anterior horn of lateral meniscus due to old tear or injury, right knee
    Billable
  61. M23.242
    Derangement of anterior horn of lateral meniscus due to old tear or injury, left knee
    Billable
  62. M23.249
    Derangement of anterior horn of lateral meniscus due to old tear or injury, unspecified knee
    Billable
  63. M23.25
    Derangement of posterior horn of lateral meniscus due to old tear or injury
    Header
  64. M23.251
    Derangement of posterior horn of lateral meniscus due to old tear or injury, right knee
    Billable
  65. M23.252
    Derangement of posterior horn of lateral meniscus due to old tear or injury, left knee
    Billable
  66. M23.259
    Derangement of posterior horn of lateral meniscus due to old tear or injury, unspecified knee
    Billable
  67. M23.26
    Derangement of other lateral meniscus due to old tear or injury
    Header
  68. M23.261
    Derangement of other lateral meniscus due to old tear or injury, right knee
    Billable
  69. M23.262
    Derangement of other lateral meniscus due to old tear or injury, left knee
    Billable
  70. M23.269
    Derangement of other lateral meniscus due to old tear or injury, unspecified knee
    Billable
  71. M23.3
    Other meniscus derangements
    Header
    Inclusion terms 3

    Inclusion terms

    • Degenerate meniscus
    • Detached meniscus
    • Retained meniscus
  72. M23.30
    Other meniscus derangements, unspecified meniscus
    Header
    Inclusion terms 2

    Inclusion terms

    • Other meniscus derangements, unspecified lateral meniscus
    • Other meniscus derangements, unspecified medial meniscus
  73. M23.300
    Other meniscus derangements, unspecified lateral meniscus, right knee
    Billable
  74. M23.301
    Other meniscus derangements, unspecified lateral meniscus, left knee
    Billable
  75. M23.302
    Other meniscus derangements, unspecified lateral meniscus, unspecified knee
    Billable
  76. M23.303
    Other meniscus derangements, unspecified medial meniscus, right knee
    Billable
  77. M23.304
    Other meniscus derangements, unspecified medial meniscus, left knee
    Billable
  78. M23.305
    Other meniscus derangements, unspecified medial meniscus, unspecified knee
    Billable
  79. M23.306
    Other meniscus derangements, unspecified meniscus, right knee
    Billable
  80. M23.307
    Other meniscus derangements, unspecified meniscus, left knee
    Billable
  81. M23.309
    Other meniscus derangements, unspecified meniscus, unspecified knee
    Billable
  82. M23.31
    Other meniscus derangements, anterior horn of medial meniscus
    Header
  83. M23.311
    Other meniscus derangements, anterior horn of medial meniscus, right knee
    Billable
  84. M23.312
    Other meniscus derangements, anterior horn of medial meniscus, left knee
    Billable
  85. M23.319
    Other meniscus derangements, anterior horn of medial meniscus, unspecified knee
    Billable
  86. M23.32
    Other meniscus derangements, posterior horn of medial meniscus
    Header
  87. M23.321
    Other meniscus derangements, posterior horn of medial meniscus, right knee
    Billable
  88. M23.322
    Other meniscus derangements, posterior horn of medial meniscus, left knee
    Billable
  89. M23.329
    Other meniscus derangements, posterior horn of medial meniscus, unspecified knee
    Billable
  90. M23.33
    Other meniscus derangements, other medial meniscus
    Header
  91. M23.331
    Other meniscus derangements, other medial meniscus, right knee
    Billable
  92. M23.332
    Other meniscus derangements, other medial meniscus, left knee
    Billable
  93. M23.339
    Other meniscus derangements, other medial meniscus, unspecified knee
    Billable
  94. M23.34
    Other meniscus derangements, anterior horn of lateral meniscus
    Header
  95. M23.341
    Other meniscus derangements, anterior horn of lateral meniscus, right knee
    Billable
  96. M23.342
    Other meniscus derangements, anterior horn of lateral meniscus, left knee
    Billable
  97. M23.349
    Other meniscus derangements, anterior horn of lateral meniscus, unspecified knee
    Billable
  98. M23.35
    Other meniscus derangements, posterior horn of lateral meniscus
    Header
  99. M23.351
    Other meniscus derangements, posterior horn of lateral meniscus, right knee
    Billable
  100. M23.352
    Other meniscus derangements, posterior horn of lateral meniscus, left knee
    Billable
  101. M23.359
    Other meniscus derangements, posterior horn of lateral meniscus, unspecified knee
    Billable
  102. M23.36
    Other meniscus derangements, other lateral meniscus
    Header
  103. M23.361
    Other meniscus derangements, other lateral meniscus, right knee
    Billable
  104. M23.362
    Other meniscus derangements, other lateral meniscus, left knee
    Billable
  105. M23.369
    Other meniscus derangements, other lateral meniscus, unspecified knee
    Billable
  106. M23.4
    Loose body in knee
    Header
  107. M23.40
    Loose body in knee, unspecified knee
    Billable
  108. M23.41
    Loose body in knee, right knee
    Billable
  109. M23.42
    Loose body in knee, left knee
    Billable
  110. M23.5
    Chronic instability of knee
    Header
  111. M23.50
    Chronic instability of knee, unspecified knee
    Billable
  112. M23.51
    Chronic instability of knee, right knee
    Billable
  113. M23.52
    Chronic instability of knee, left knee
    Billable
  114. M23.6
    Other spontaneous disruption of ligament(s) of knee
    Header
  115. M23.60
    Other spontaneous disruption of unspecified ligament of knee
    Header
  116. M23.601
    Other spontaneous disruption of unspecified ligament of right knee
    Billable
  117. M23.602
    Other spontaneous disruption of unspecified ligament of left knee
    Billable
  118. M23.609
    Other spontaneous disruption of unspecified ligament of unspecified knee
    Billable
  119. M23.61
    Other spontaneous disruption of anterior cruciate ligament of knee
    Header
  120. M23.611
    Other spontaneous disruption of anterior cruciate ligament of right knee
    Billable
  121. M23.612
    Other spontaneous disruption of anterior cruciate ligament of left knee
    Billable
  122. M23.619
    Other spontaneous disruption of anterior cruciate ligament of unspecified knee
    Billable
  123. M23.62
    Other spontaneous disruption of posterior cruciate ligament of knee
    Header
  124. M23.621
    Other spontaneous disruption of posterior cruciate ligament of right knee
    Billable
  125. M23.622
    Other spontaneous disruption of posterior cruciate ligament of left knee
    Billable
  126. M23.629
    Other spontaneous disruption of posterior cruciate ligament of unspecified knee
    Billable
  127. M23.63
    Other spontaneous disruption of medial collateral ligament of knee
    Header
  128. M23.631
    Other spontaneous disruption of medial collateral ligament of right knee
    Billable
  129. M23.632
    Other spontaneous disruption of medial collateral ligament of left knee
    Billable
  130. M23.639
    Other spontaneous disruption of medial collateral ligament of unspecified knee
    Billable
  131. M23.64
    Other spontaneous disruption of lateral collateral ligament of knee
    Header
  132. M23.641
    Other spontaneous disruption of lateral collateral ligament of right knee
    Billable
  133. M23.642
    Other spontaneous disruption of lateral collateral ligament of left knee
    Billable
  134. M23.649
    Other spontaneous disruption of lateral collateral ligament of unspecified knee
    Billable
  135. M23.67
    Other spontaneous disruption of capsular ligament of knee
    Header
  136. M23.671
    Other spontaneous disruption of capsular ligament of right knee
    Billable
  137. M23.672
    Other spontaneous disruption of capsular ligament of left knee
    Billable
  138. M23.679
    Other spontaneous disruption of capsular ligament of unspecified knee
    Billable
  139. M23.8
    Other internal derangements of knee
    Header
    Inclusion terms 2

    Inclusion terms

    • Laxity of ligament of knee
    • Snapping knee
  140. M23.8X
    Other internal derangements of knee
    Header
  141. M23.8X1
    Other internal derangements of right knee
    Billable
  142. M23.8X2
    Other internal derangements of left knee
    Billable
  143. M23.8X9
    Other internal derangements of unspecified knee
    Billable
  144. M23.9
    Unspecified internal derangement of knee
    Header
  145. M23.90
    Unspecified internal derangement of unspecified knee
    Billable
  146. M23.91
    Unspecified internal derangement of right knee
    Billable
  147. M23.92
    Unspecified internal derangement of left knee
    Billable

Sources of each column.

Instructions

At M23

Excludes1

  • ankylosis (M24.66) M24.66
  • deformity of knee (M21.-) M21
  • osteochondritis dissecans (M93.2) M93.2

Excludes2

  • current injury - see injury of knee and lower leg (S80-S89) S80 S89
  • recurrent dislocation or subluxation of joints (M24.4) M24.4
  • recurrent dislocation or subluxation of patella (M22.0-M22.1) M22.0 M22.1

Notes that also apply

Block M20-M25 instructions (Excludes2 1): printed on the block page.

Instructions for the group M00-M25 (Includes 1): printed on the chapter 13 page.

Chapter 13 instructions (Notes 1, Excludes2 10): printed on the chapter 13 page.

Index entries

  • Mice, jointknee → M23.4-
  • Mouse, jointknee → M23.4-
  • Rice bodiesknee → M23.4-
  • Instabilityknee (chronic) → M23.5-
  • Derangementknee (recurrent) → M23.9-
  • Derangementknee (recurrent)meniscus → M23.30-
  • Body, bodiesriceknee → M23.4-
  • Derangementknee (recurrent)loose body → M23.4-
  • Jointmiceknee → M23.4-
  • Loosebodyknee → M23.4-
  • Derangementknee (recurrent)ligament disruption, spontaneous → M23.60-
  • Derangementknee (recurrent)specified NEC → M23.8
  • Adhesions, adhesive (postinfective)jointknee → M23.8X
  • Derangementknee (recurrent)old → M23.8X-
  • Destruction, destructivearticular facetknee → M23.8X-
  • Dislocation (articular)kneeold → M23.8X-
  • Derangementknee (recurrent)meniscuscystic → M23.0-
  • Derangementknee (recurrent)meniscusdue to old tear or injury → M23.20-
  • Derangementknee (recurrent)meniscusspecified NEC → M23.30-
  • Body, bodiesloosejoint, except kneeknee → M23.4-
  • Loosebodyjointknee → M23.4-
  • Derangementknee (recurrent)ligament disruption, spontaneousinstability, chronic → M23.5-
  • Derangementknee (recurrent)ligament disruption, spontaneousanterior cruciate → M23.61-
  • Derangementknee (recurrent)ligament disruption, spontaneousposterior cruciate → M23.62-
  • Derangementknee (recurrent)ligament disruption, spontaneousmedial collateral → M23.63-
  • Derangementknee (recurrent)ligament disruption, spontaneouslateral collateral → M23.64-
  • Derangementknee (recurrent)ligament disruption, spontaneouscapsular → M23.67-
  • Derangementjoint (internal)articular cartilageknee NEC → M23.9-
  • Derangementknee (recurrent)meniscuscysticlateral → M23.002
  • Derangementknee (recurrent)meniscuscysticmedial → M23.005
  • Derangementknee (recurrent)meniscusdue to old tear or injurylateral → M23.20-
  • Derangementknee (recurrent)meniscusdue to old tear or injurymedial → M23.20-
  • Derangementknee (recurrent)meniscusspecified NEClateral → M23.30-
  • Derangementknee (recurrent)meniscusspecified NECmedial → M23.30-
  • Derangementknee (recurrent)meniscuscysticmedialanterior horn → M23.01-
  • Derangementknee (recurrent)meniscuscysticmedialposterior horn → M23.02-
  • Derangementknee (recurrent)meniscuscysticmedialspecified NEC → M23.03-
  • Derangementknee (recurrent)meniscuscysticlateralanterior horn → M23.04-
  • Derangementknee (recurrent)meniscuscysticlateralposterior horn → M23.05-
  • Derangementknee (recurrent)meniscuscysticlateralspecified NEC → M23.06-

12 more, longer entries are not listed; the search box finds them by word.

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Hierarchy