M79.4 Hypertrophy of (infrapatellar) fat pad

Billable ICD-10-CM code, FY2026.

Applies from M79 Other and unspecified soft tissue disorders, not elsewhere classified

Excludes1 (never code together)

• psychogenic rheumatism (F45.8)
• soft tissue pain, psychogenic (F45.41)

MS-DRG index

Defines the logic of DRG(s) 606-607 in MDC 09.

Approximate ICD-9-CM (GEMs)

• 729.31 Hypertrophy of fat pad, knee

Diagnosis Index entries for M79.4

• Degeneration, degenerative › infrapatellar fat pad
• Degeneration, degenerative › popliteal fat pad
• Fat › localized (pad) › knee
• Fat › localized (pad) › retropatellar
• Fat › pad › knee
• Fibrosis, fibrotic › infrapatellar fat pad
• Fibrosis, fibrotic › popliteal fat pad
• Hypertrophy, hypertrophic › fat pad › knee (infrapatellar) (popliteal) (prepatellar) (retropatellar)

Nearby codes

• M79.11 Myalgia of mastication muscle
• M79.12 Myalgia of auxiliary muscles, head and neck
• M79.18 Myalgia, other site
• M79.2 Neuralgia and neuritis, unspecified
• M79.3 Panniculitis, unspecified
• M79.4 Hypertrophy of (infrapatellar) fat pad (this code)
• M79.5 Residual foreign body in soft tissue
• M79.6 Pain in limb, hand, foot, fingers and toes
• M79.60 Pain in limb, unspecified
• M79.601 Pain in right arm
• M79.602 Pain in left arm