T84.039A Mechanical loosening of unspecified internal prosthetic joint, initial encounter

Billable ICD-10-CM code, FY2026.

Built from T84.039 with 7th character A (initial encounter).

Applies from T84 Complications of internal orthopedic prosthetic devices, implants and grafts

Excludes2 (not included here)

• failure and rejection of transplanted organs and tissues (T86.-)
• fracture of bone following insertion of orthopedic implant, joint prosthesis or bone plate (M96.6)

7th character note

• The appropriate 7th character is to be added to each code from category T84

7th character required

• A — initial encounter
• D — subsequent encounter
• S — sequela

Applies from T84.03 Mechanical loosening of internal prosthetic joint

Applicable to

• Aseptic loosening of prosthetic joint

Risk adjustment (HCC)

• CMS-HCC V22: HCC 176 — Complications of Specified Implanted Device or Graft
• ESRD V24: HCC 176

Medicare Code Edits (MCE v43.1 (April 2026))

• Unspecified code (laterality): Unspecified codes for which a more specific code identifying laterality (right, left, bilateral) exists within the same code family.

Code annotations containing back-references to T84.039A

Back-references to T84.0

• Type 2 Excludes: T81.59 Other complications of foreign body accidentally left in body following procedure ("obstruction or perforation due to prosthetic devices and implants intentionally left in body (T82.0-T82.5, T83.0-T83.4, T83.7, T84.0-T84.4, T85.0-T85.6)")

Back-references to T84

• Type 2 Excludes: M96 Intraoperative and postprocedural complications and disorders of musculoskeletal system, not elsewhere classified ("complications of internal orthopedic prosthetic devices, implants and grafts (T84.-)")
• Type 2 Excludes: M96.6 Fracture of bone following insertion of orthopedic implant, joint prosthesis, or bone plate ("complication of internal orthopedic devices, implants or grafts (T84.-)")
• Type 2 Excludes: T78 Adverse effects, not elsewhere classified ("complications of surgical and medical care NEC (T80-T88)")
• Type 2 Excludes: T79 Certain early complications of trauma, not elsewhere classified ("complications occurring during or following medical procedures (T80-T88)")
• Type 2 Excludes: T79 Certain early complications of trauma, not elsewhere classified ("complications of surgical and medical care NEC (T80-T88)")
• Type 2 Excludes: T81 Complications of procedures, not elsewhere classified ("complication of prosthetic devices, implants and grafts (T82-T85)")
• Type 2 Excludes: T88 Other complications of surgical and medical care, not elsewhere classified ("complications of devices, implants and grafts (T82-T85)")
• Type 2 Excludes: Z96 Presence of other functional implants ("complications of internal prosthetic devices, implants and grafts (T82-T85)")
• Type 1 Excludes: Z97 Presence of other devices ("complications of internal prosthetic devices, implants and grafts (T82-T85)")

Diagnosis Index entries for T84.039A

• Complication (s) (from) (of) › joint prosthesis, internal › mechanical › loosening

Nearby codes

• T84.038 Mechanical loosening of other internal prosthetic joint
• T84.038A Mechanical loosening of other internal prosthetic joint, initial encounter
• T84.038D Mechanical loosening of other internal prosthetic joint, subsequent encounter
• T84.038S Mechanical loosening of other internal prosthetic joint, sequela
• T84.039 Mechanical loosening of unspecified internal prosthetic joint
• T84.039A Mechanical loosening of unspecified internal prosthetic joint, initial encounter (this code)
• T84.039D Mechanical loosening of unspecified internal prosthetic joint, subsequent encounter
• T84.039S Mechanical loosening of unspecified internal prosthetic joint, sequela
• T84.05 Periprosthetic osteolysis of internal prosthetic joint
• T84.050 Periprosthetic osteolysis of internal prosthetic right hip joint
• T84.050A Periprosthetic osteolysis of internal prosthetic right hip joint, initial encounter