Flank

Flank. Such a small word which means the anatomic area on the side of a person’s body between the ribs and hips. However, until the FY2026 ICD-10-CM code updates, the diagnosis code for flank pain was lumped in with the anatomic site abdomen. This segment of “In the kNOW”, will share the new codes related to flank pain and other conditions that will be codable specifically to the flank which, by the way, accounts for 138 of the changes to ICD-10-CM for FY2026.

Source: https://kleinlipo.com/abs-flanks/


We’ll begin with the flank pain codes.

This is the tabular list entry for flank pain. Laterality is a key component when assigning flank codes.

R10.A Pain localized to flank

Lateral abdomen pain

Lateral flank pain

Latus region pain

Excludes2: pain localized to other parts of lower abdomen (R10.3-)

         pain localized to upper abdomen (R10.1-)

R10.A0 Flank pain, unspecified side 

R10.A1 Flank pain, right side
R10.A2 Flank pain, left side
R10.A3 Flank pain, bilateral

Coding professionals are also able to code flank tenderness as expressed by the codes below:

R10.8A1 Right flank tenderness
R10.8A2 Left flank tenderness
R10.8A3 Suprapubic tenderness
R10.8A9 Flank tenderness, unspecified 

               Flank tenderness NOS

The use of the anatomic site “flank” has also impacted other conditions, everything from the site of abscesses and cellulitis to superficial injuries. Those are reflected with the codes below:

L02.217 Cutaneous abscess of flank
L02.227 Furuncle of flank
L03.31A Cellulitis of flank
L03.32A Acute lymphangitis of flank
S30.13 Contusion of flank (latus) region
S30.81A Abrasion of flank
S30.82A Blister (nonthermal) of flank
S30.84A External constriction of flank
S30.85A Superficial foreign body of flank
S30.86A Insect bite (nonvenomous) of flank
S30.87A Other superficial bite of flank
S30.9A Unspecified superficial injury of flank

The subcategories below have all added sixth characters of 6, 7, and A to specify the laterality of the open wound injuries of the flank:

S31.10 Unspecified open wound of abdominal wall, flank without penetration into peritoneal cavity
S31.11 Laceration without foreign body of abdominal wall, right flank without penetration into

  peritoneal cavity

S31.12 Laceration with foreign body of abdominal wall, right flank without penetration into

  peritoneal cavity

S31.13 Puncture wound of abdominal wall without foreign body, right flank without penetration

  into peritoneal cavity

S31.14 Puncture wound of abdominal wall with foreign body, right flank without penetration

  into peritoneal cavity

S31.15 Open bite of abdominal wall, right flank without penetration into peritoneal cavity
S31.60 Unspecified open wound of abdominal wall, right flank with penetration into peritoneal
S31.61 Laceration without foreign body of abdominal wall, right flank with penetration into

  peritoneal cavity

S31.62 Laceration with foreign body of abdominal wall, right flank with penetration into

  peritoneal cavity

S31.63 Puncture wound of abdominal wall without foreign body, right flank with penetration

  into peritoneal cavity

S31.64 Puncture wound of abdominal wall with foreign body, right flank with penetration into

  peritoneal cavity

S31.65 Open bite of abdominal wall, right flank with penetration into peritoneal cavity

Now this anatomic location has its rightful place in the ICD-10-CM world, and 
Now you are In the kNOW!!

About the Author

Dianna Foley, RHIA, CCS, CDIP, CHPS, has 25 years of HIM experience. She earned her bachelor’s degree from the University of Cincinnati and holds RHIA, CHPS, CDIP, and CCS certifications from AHIMA. Dianna’s an AHIMA-approved ICD-10-CM/PCS trainer, an AHIMA-published author, a participant in AHIMA credential item writing and exam development, and served on the AHIMA Nominating Committee. Dianna has held various HIM positions and is now an independent coding consultant. She previously served as a program director for Medical Coding and HIT. She presents on coding topics at the national, state, and regional levels and serves as OHIMA’s Education Coordinator.