ICD-10-PCS Root Operation Groups

By Ann Zeisset, RHIT, CCS, CCS-P

Root Operations that Take Out Some or All of a Body Part

The medical and surgical procedure section of ICD-10-PCS contains most, but not all, procedures typically reported in the hospital inpatient setting. As with all codes in ICD-10-PCS, the medical and surgical procedure codes contain seven characters, with each character representing one particular aspect of the procedure. The third character defines the root operation, or the objective of the procedure.

This article is the first in a series of articles that explains ICD-10-PCS root operation groupings in this important and largest section of ICD-10-PCS.

ICD-10-PCS Root Operations

There are 31 root operations in the medical and surgical section, which are arranged in groups with similar attributes (see the table “Medical and Surgical Section Root Operations” on page 59 for an alphabetical listing of all 31 root operations in the medical and surgical section).

The 31 root operations are arranged into the following groupings:

  • Root operations that take out some/all of a body part
  • Root operations that take out solids/fluids/gasses from a body part
  • Root operations involving cutting or separation only
  • Root operations that put in/put back or move some/all of a body part
  • Root operations that alter the diameter/route of a tubular body part
  • Root operations that always involve a device
  • Root operations involving examination only
  • Root operations that include other repairs
  • Root operations that include other objectives

If multiple procedures (as defined by distinct objectives) are performed, then multiple codes are assigned. The term anastomosis is not a root operation because it is a means of joining and is an integral part of another procedure such as a bypass or a resection. Therefore, it never stands alone. Incision is not a root term because it is a means of opening and is always an integral part of another procedure.

Root Operations that Take Out Some or All of a Body Part

The first grouping includes the following root operations:

  • Excision
  • Resection
  • Detachment
  • Destruction
  • Extraction

Excision-Root Operation B

Excision is used when a sharp instrument is used to cut out or off a portion of a body part without replacement. All root operations employing cutting to accomplish the objective allow the use of any sharp instrument, including but not limited to:

  • Scalpel
  • Wire
  • Scissors
  • Bone saw
  • Electrocautery tip

The qualifier “diagnostic” is available to identify excision procedures that are biopsies.

Examples of excision are partial nephrectomy, liver biopsy, breast lumpectomy, excision of cyst, sigmoid polypectomy, or excision of melanoma.

Bone marrow and endometrial biopsies are not coded to excision. Instead they are coded to the root operation extraction, with the qualifier diagnostic used to identify the biopsy.

If a diagnostic excision (biopsy) is followed by a therapeutic excision at the same procedure site or resection of the body part during the same operative episode, only the therapeutic excision or resection is coded (e.g., for a breast biopsy followed by partial mastectomy at the same procedure site, only the partial mastectomy procedure is coded).

Medical and Surgical Section Root Operations

The medical and surgical procedure section contains 31 root operations, which are arranged in groups with similar attributes. The root operations are:
































Resection-Root Operation T

Resection is similar to excision except it involves cutting out or off, without replacement, all of a body part. Resection includes all of a body part or any subdivision of a body part having its own body part value in ICD-10-PCS, while excision includes only a portion of a body part.

Examples of resection are total nephrectomy, total lobectomy of lung, total mastectomy, resection cecum, prostatectomy, or cholecystectomy.

Resection of a specific anatomical subdivision body part is coded whenever possible, rather than excision of the less specific body part (e.g., right upper lung lobectomy is coded to resection of upper lung lobe, right, and not to excision of lung, right).

The important distinction between excision and resection is if a portion or the entire body part is excised. A body part in ICD-10-PCS is not always an entire organ with some body part values being a subdivision of a particular organ. However, the body part value may be an entire organ, such as the organs of the gallbladder, prostate, or appendix.

When a procedure is performed on the body part, it is necessary to know if the entire body part was excised. A prostatectomy is the removal of the prostate, while a transurethral resection of the prostate removes the section of the prostate causing symptoms.

Some organs such as the liver, stomach, and lung have subdivisions of body parts. The liver contains right lobe and left lobe, the stomach includes the pylorus as a specific body part, and the lung has multiple body parts such as right and left upper lobe, right middle lobe, and right and left lower lobe.

Therefore if the entire right middle lobe of the lung was removed, resection would be assigned rather than excision, because this is a complete body part per ICD-10-PCS.

When an entire lymph node chain is cut out, the appropriate root operation is resection. When a lymph node(s) is cut out, the root operation is excision.

Detachment-Root Operation 6

Detachment is defined as cutting off all or part of the upper or lower extremities. It represents a narrow range of procedures and is used exclusively for amputation procedures.

Detachment procedure codes are found only in body systems X (anatomical regions, upper extremities) and Y (anatomical regions, lower extremities) because amputations are performed on extremities across overlapping body layers.

The body part value is the site of the detachment, with a qualifier if applicable to further specify the level where the extremity was detached. The specific qualifiers used for detachment are dependent on the body part value.

Examples of detachment are below knee amputation, disarticulation of shoulder, amputation above elbow, or transmetatarsal amputation of foot at right big toe.

Destruction-Root Operation 5

Destruction is defined as the physical eradication of all or a portion of a body part by the direct use of energy, force, or a destructive agent. Common terms that may be documented are ablation, destruction, fulguration, cryotherapy, and cautery.

In destruction, none of the body part is physically taken out, instead it obliterates a body part so it is no longer there. This root operation defines a broad range of common procedures, since it can be used anywhere in the body to treat a variety of conditions, including skin and genital warts, nasal and colon polyps, esophageal varices, endometrial implants, and nerve lesions.

Examples of destruction are fulguration of rectal polyp, cautery of skin lesion, fulguration of endometrium, ablation of endometriosis, or cryotherapy of warts.

Meaning of Characters for Medical and Surgical Procedures

The main section of ICD-10-PCS, the medical and surgical section, has the following meanings for the seven characters.

1 2 3 4 5 6 7
Section Body System Root Operation Body Part Approach Device Qualifier

Extraction-Root Operation D

Extraction is defined as pulling or stripping out or off all or a portion of a body part by the use of force. Minor cutting, such as that used in vein stripping procedures, is included in extraction if the objective of the procedure is met by pulling or stripping.

As with all applicable ICD-10-PCS codes, cutting used to reach the procedure site is specified in the approach value. Extraction procedures that are biopsies may also be identified with the qualifier “diagnostic.”

Examples of extraction are dilation and curettage, vein stripping, suction dilation and curettage, phacoemulsification without intraocular lens implant, nonexcisional debridement of skin, extraction of teeth, bone marrow biopsy, endometrial biopsy, or liposuction for medical purposes.

Coding professionals should be careful of terminology when coding in ICD-10-PCS. Coding professionals should convert common terminology to the appropriate root operation according to the intent of the procedure based on its definition.

For example, the procedure documentation may say removal, but in actuality, using ICD-10-PCS definitions, an extraction was performed (e.g., removal of a thumbnail would be coded to extraction). The root operation of removal is not correct because by definition a removal in ICD-10-PCS is defined as taking out or off a device from a body part.


Centers for Medicare and Medicaid Services (CMS). “2009 Code Tables and Index.” Available online at www.cms.hhs.gov/ICD10/01m_2009_ICD10PCS.asp#TopOfPage

CMS. “2009 ICD-10-PCS Reference Manual.” Available online at www.cms.hhs.gov/ICD10/01m_2009_ICD10PCS.asp#TopOfPage

CMS. “ICD-10-PCS Draft Coding Guidelines.” Appendix B in “ICD-10-PCS Reference Manual.” 2009. Available online at www.cms.hhs.gov/ICD10/01k_2010_ICD10PCS.asp#TopOfPage.

Ann Zeisset (ann.zeisset@ahima.org) is a professional practice resource manager at AHIMA.

Article citation:
Zeisset, Ann M.. "ICD-10-PCS Root Operation Groups" Journal of AHIMA 81, no.3 (March 2010): 58-60.