{"code":"M23.021","type":"code","title":"Cystic meniscus, posterior horn of medial meniscus, right knee","codeAlso":[],"includes":[],"modern_v":"official26","codeFirst":[],"excludes1":["ankylosis (M24.66)","deformity of knee (M21.-)","osteochondritis dissecans (M93.2)"],"excludes2":["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)","joints of the spine (M40-M54)"],"isBillable":true,"fyEffectivity":{"fy2026":true,"fy2027":true,"billableFy2026":true,"billableFy2027":true},"sibling_codes":["M23","M23.0","M23.00","M23.000","M23.001","M23.002","M23.003","M23.004","M23.005","M23.006","M23.007","M23.009","M23.01","M23.011","M23.012","M23.019","M23.02","M23.022","M23.029","M23.03","M23.031","M23.032","M23.039","M23.04","M23.041","M23.042","M23.049","M23.05","M23.051","M23.052","M23.059","M23.06","M23.061","M23.062","M23.069","M23.2","M23.20","M23.200","M23.201","M23.202","M23.203","M23.204","M23.205","M23.206","M23.207","M23.209","M23.21","M23.211","M23.212","M23.219","M23.22","M23.221","M23.222","M23.229","M23.23","M23.231","M23.232","M23.239","M23.24","M23.241","M23.242","M23.249","M23.25","M23.251","M23.252","M23.259","M23.26","M23.261","M23.262","M23.269","M23.3","M23.30","M23.300","M23.301","M23.302","M23.303","M23.304","M23.305","M23.306","M23.307","M23.309","M23.31","M23.311","M23.312","M23.319","M23.32","M23.321","M23.322","M23.329","M23.33","M23.331","M23.332","M23.339","M23.34","M23.341","M23.342","M23.349","M23.35","M23.351","M23.352"],"inclusionTerms":[],"sibling_titles":{"code":"M23.352","title":"Other meniscus derangements, posterior horn of lateral meniscus, left knee","isBillable":true},"useAdditionalCode":[],"clinicalDefinition":"Cystic meniscus, posterior horn of medial meniscus, right knee is a billable ICD-10-CM diagnosis code (M23.021). Excludes1 (not coded here): ankylosis (M24.66); deformity of knee (M21.-); osteochondritis dissecans (M93.2). Excludes2 (not included here): 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); joints of the spine (M40-M54).","officialDefinition":"Cystic meniscus, posterior horn of medial meniscus, right knee is a billable ICD-10-CM diagnosis code (M23.021). Excludes1 (not coded here): ankylosis (M24.66); deformity of knee (M21.-); osteochondritis dissecans (M93.2). Excludes2 (not included here): 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); joints of the spine (M40-M54).","seventhCharacterInstructions":[],"workflowProtocols":[],"guidelines":{"whenToUse":[],"whenNotToUse":[],"commonBillingMistakes":[],"codeComparisons":[],"documentationChecklist":[]},"domainLandscape":{"summary":"Primary diagnostic domain and clinical landscape evaluation.","keyCategories":[],"diagnosticContinuum":"Progression continuum from acute presentation to resolution."},"children":[],"hierarchy":[],"relatedCodes":[],"relevantCPTCodes":[],"documentationTips":[],"caseStudies":[],"description":"","overview":"","noteProvenance":{"ankylosis (M24.66)":"M23","deformity of knee (M21.-)":"M23","osteochondritis dissecans (M93.2)":"M23","current injury - see injury of knee and lower leg (S80-S89)":"M23","recurrent dislocation or subluxation of joints (M24.4)":"M23","recurrent dislocation or subluxation of patella (M22.0-M22.1)":"M23","joints of the spine (M40-M54)":"M23"},"hcc":{"mapped":false,"model":"CMS-HCC V28","paymentYear":"2026","categories":[],"otherModels":[]}}