S83.4 – Sprain of collateral ligament of knee

ICD-10-CM 2027 diagnosis code · Injuries to the knee and lower leg

Non-billable header

ICD-10-CM code S83.4

Code: S83.4 (claims format: S834)
Description: Sprain of collateral ligament of knee
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 19. Injury, poisoning and certain other consequences of external causes (S00-T88)
Block: S80-S89 Injuries to the knee and lower leg
Parent codes: S83

Billable codes under S83.4

S83.4 is a header code and cannot be used on claims. Choose the most specific code:

S83.40 – Sprain of unspecified collateral ligament of kneeHeader (more codes below)
S83.41 – Sprain of medial collateral ligament of kneeHeader (more codes below)
S83.42 – Sprain of lateral collateral ligament of kneeHeader (more codes below)

7th character values

Codes in this category need a 7th character to describe the encounter or episode of care (use placeholder X for empty positions).

Character	Meaning
`A`	initial encounter
`D`	subsequent encounter
`S`	sequela

Notes inherited from parent codes

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

S83 – Dislocation and sprain of joints and ligaments of knee

Includes:

avulsion of joint or ligament of knee
laceration of cartilage, joint or ligament of knee
sprain of cartilage, joint or ligament of knee
traumatic hemarthrosis of joint or ligament of knee
traumatic rupture of joint or ligament of knee
traumatic subluxation of joint or ligament of knee
traumatic tear of joint or ligament of knee

Excludes2 (not included here):

derangement of patella (M22.0-M22.3)
injury of patellar ligament (tendon) (S76.1-)
internal derangement of knee (M23.-)
old dislocation of knee (M24.36)
pathological dislocation of knee (M24.36)
recurrent dislocation of knee (M22.0)
strain of muscle, fascia and tendon of lower leg (S86.-)

Code also:

any associated open wound

7th character note:

The appropriate 7th character is to be added to each code from category S83

Block S80-S89

Excludes2 (not included here):

burns and corrosions (T20-T32)
frostbite (T33-T34)
injuries of ankle and foot, except fracture of ankle and malleolus (S90-S99)
insect bite or sting, venomous (T63.4)

Related codes in S83

Frequently asked questions

What is ICD-10 code S83.4?

S83.4 is the ICD-10-CM code for sprain of collateral ligament of knee, in the block S80-S89 (Injuries to the knee and lower leg).

Is S83.4 a billable code?

No. S83.4 is a header code with more specific child codes; report one of the billable codes listed above.

What category does S83.4 belong to?

It belongs to category S83 – Dislocation and sprain of joints and ligaments of knee.

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.