S23.420S – Sprain of sternoclavicular (joint) (ligament), sequela

ICD-10-CM 2027 diagnosis code · Injuries to the thorax

Deleted Oct 1, 2026

ICD-10-CM code S23.420S
Code
S23.420S (claims format: S23420S)
Description
Sprain of sternoclavicular (joint) (ligament), sequela
Billable
No – deleted from the code set
Chapter
19. Injury, poisoning and certain other consequences of external causes (S00-T88)
Block
S20-S29 Injuries to the thorax
Parent codes
S23 › S23.4 › S23.42

This code was deleted

S23.420S (Sprain of sternoclavicular (joint) (ligament), sequela) is not valid for dates of service on or after October 1, 2026. See S23.42 for the current codes in this category.

7th character values

Codes in this category need a 7th character to describe the encounter or episode of care.

CharacterMeaning
Ainitial encounter
Dsubsequent encounter
Ssequela

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

S23 – Dislocation and sprain of joints and ligaments of thorax

Includes:
  • avulsion of joint or ligament of thorax
  • laceration of cartilage, joint or ligament of thorax
  • sprain of cartilage, joint or ligament of thorax
  • traumatic hemarthrosis of joint or ligament of thorax
  • traumatic rupture of joint or ligament of thorax
  • traumatic subluxation of joint or ligament of thorax
  • traumatic tear of joint or ligament of thorax
Excludes2 (not included here):
  • dislocation, sprain of sternoclavicular joint (S43.2, S43.6)
  • strain of muscle or tendon of thorax (S29.01-)
Code also:
  • any associated open wound
7th character note:
  • The appropriate 7th character is to be added to each code from category S23

Block S20-S29

Includes:
  • injuries of breast
  • injuries of chest (wall)
  • injuries of interscapular area
Excludes2 (not included here):
  • burns and corrosions (T20-T32)
  • effects of foreign body in bronchus (T17.5)
  • effects of foreign body in esophagus (T18.1)
  • effects of foreign body in lung (T17.8)
  • effects of foreign body in trachea (T17.4)
  • frostbite (T33-T34)
  • injuries of axilla
  • injuries of clavicle
  • injuries of scapular region
  • injuries of shoulder
  • insect bite or sting, venomous (T63.4)

Related codes in S23.42

Frequently asked questions

What is ICD-10 code S23.420S?

S23.420S is the ICD-10-CM code for sprain of sternoclavicular (joint) (ligament), sequela, in the block S20-S29 (Injuries to the thorax).

Is S23.420S a billable code?

No. It was deleted effective October 1, 2026.

What category does S23.420S belong to?

It belongs to category S23 – Dislocation and sprain of joints and ligaments of thorax.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.