Coding Ahead
CasePilot
Medical Coding Assistant
Case2Code
Search and Code Lookup Tool
RedactPHI
HIPAA-Compliant PHI Redaction
DetectICD10CM
ICD-10-CM Code Detection
Log in Register free account
1 code page views remaining. Guest accounts are limited to 1 page view. Register free account to get 5 more views.
Log in Register free account

Official Description

Incision, deep, with opening of bone cortex, femur or knee (eg, osteomyelitis or bone abscess)

© Copyright 2025 American Medical Association. All rights reserved.

Common Language Description

The procedure described by CPT® Code 27303 involves a deep incision that opens the bone cortex of the femur or knee, specifically targeting conditions such as osteomyelitis or a bone abscess. Osteomyelitis refers to an infection of the bone, while a bone abscess is a localized collection of pus within the bone. During this surgical intervention, an incision is made through the skin and soft tissue to access the infected area of the bone. The periosteum, which is the dense layer of vascular connective tissue enveloping the bones, is carefully elevated to expose the underlying cortical bone. A small section, or button, of the cortical bone is then removed to access the bone marrow, which is crucial for alleviating pressure caused by inflammation. This step is vital as it helps restore blood flow to the affected area, which is often compromised due to the infection. If pus is present, the initial opening may be enlarged using specialized instruments such as a chisel or gouge, allowing for better drainage and treatment of the abscess. In cases where the epiphysis, the end part of a long bone, is involved, a portion of the epiphyseal cortex may also be excised to ensure complete drainage and treatment of the infection.

© Copyright 2025 Coding Ahead. All rights reserved.

1. Indications

The procedure described by CPT® Code 27303 is indicated for specific conditions that affect the bone, particularly in the femur or knee region. The primary indications for performing this procedure include:

  • Osteomyelitis - A serious infection of the bone that can lead to bone destruction and requires surgical intervention to remove infected tissue and promote healing.
  • Bone Abscess - A localized collection of pus within the bone that necessitates drainage to alleviate pain, pressure, and prevent further complications.

2. Procedure

The procedure involves several critical steps to ensure effective treatment of the infected bone. These steps include:

  • Step 1: Incision - A surgical incision is made through the skin and soft tissue over the site of the infected bone. This initial step is crucial for gaining access to the underlying structures that require treatment.
  • Step 2: Elevation of the Periosteum - Once the incision is made, the periosteum, which is the protective layer surrounding the bone, is carefully elevated. This allows the surgeon to visualize and access the cortical bone that is affected by the infection.
  • Step 3: Removal of Cortical Bone Button - A small button of cortical bone is removed to expose the underlying bone marrow. This step is essential for relieving pressure caused by inflammation and ensuring that blood flow to the infected area is restored.
  • Step 4: Enlargement of the Opening - If pus is encountered during the procedure, the initial opening may be enlarged using a chisel or gouge. This extension allows for better drainage of the abscess and thorough cleaning of the infected area.
  • Step 5: Removal of Epiphyseal Cortex (if necessary) - In cases where the infection involves the epiphysis, a section of the epiphyseal cortex may be removed to ensure complete drainage and treatment of the infection.

3. Post-Procedure

After the procedure, appropriate post-operative care is essential for recovery. This may include monitoring for signs of infection, managing pain, and ensuring proper wound care. Patients may require follow-up visits to assess healing and to ensure that the infection has been adequately addressed. Rehabilitation may also be necessary to restore function and strength in the affected limb, depending on the extent of the procedure and the patient's overall health status.

Short Descr DRAINAGE OF BONE LESION
Medium Descr INC DEEP W/OPNG BONE CORTEX FEMUR/KNEE
Long Descr Incision, deep, with opening of bone cortex, femur or knee (eg, osteomyelitis or bone abscess)
Status Code Active Code
Global Days 090 - Major Surgery
PC/TC Indicator (26, TC) 0 - Physician Service Code
Multiple Procedures (51) 2 - Standard payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 1 - 150% payment adjustment for bilateral procedures applies.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 2 - Payment restriction for assistants at surgery does not apply to this procedure...
Co-Surgeons (62) 1 - Co-surgeons could be paid, though supporting documentation is required...
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Inpatient Procedures, not paid under OPPS
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P5B - Ambulatory procedures - musculoskeletal
MUE 2
CCS Clinical Classification 161 - Other OR therapeutic procedures on bone

This is a primary code that can be used with these additional add-on codes.

20700 Add-on Code MPFS Status: Active Code APC N ASC N1 Manual preparation and insertion of drug-delivery device(s), deep (eg, subfascial) (List separately in addition to code for primary procedure)
22 Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service.
50 Bilateral procedure: unless otherwise identified in the listings, bilateral procedures that are performed at the same session, should be identified by adding modifier 50 to the appropriate 5 digit code. note: this modifier should not be appended to designated "add-on" codes (see appendix d).
51 Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d).
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
79 Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.)
80 Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s).
82 Assistant surgeon (when qualified resident surgeon not available): the unavailability of a qualified resident surgeon is a prerequisite for use of modifier 82 appended to the usual procedure code number(s).
AS Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery
GC This service has been performed in part by a resident under the direction of a teaching physician
GW Service not related to the hospice patient's terminal condition
LT Left side (used to identify procedures performed on the left side of the body)
RT Right side (used to identify procedures performed on the right side of the body)
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
Date
Action
Notes
Pre-1990 Added Code added.
Code
Description
Code
Description
Code
Description
Code
Description
Code
Description
CasePilot

Get instant expert-level medical coding assistance.

Ask about:
CPT Codes Guidelines Modifiers Crosswalks NCCI Edits Compliance Medicare Coverage
Example: "What is CPT code 99213?" or "Guidelines for E/M services"