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Official Description

Open treatment of sesamoid fracture, with or without internal fixation

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 28531 refers to the open treatment of a sesamoid fracture, which may involve internal fixation. A sesamoid fracture occurs in the foot, specifically affecting the small sesamoid bones that are embedded within tendons. In the context of the foot, there are two primary sesamoid bones located beneath the great toe joint, situated in the ball of the foot. These bones play a crucial role in the mechanics of the foot, aiding in weight-bearing and movement. When a fracture occurs, it is essential to obtain separate radiographs to confirm the presence and extent of the fracture. A thorough neurovascular examination is also performed to assess the integrity of the nerves and blood vessels surrounding the injury site, ensuring that there is no compromise to these critical structures. The treatment approach may vary depending on the nature of the fracture; for instance, in cases of nondisplaced or minimally displaced fractures, closed treatment may be sufficient, as described in CPT® Code 28530. However, for more complex fractures requiring surgical intervention, the open treatment described in CPT® Code 28531 is indicated. This procedure involves exposing the fractured sesamoid bone, which may lead to the excision of fracture fragments or, less commonly, the reduction of the bone back to its proper alignment, potentially utilizing internal fixation methods such as pins or wires to secure the fragments in place.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The open treatment of a sesamoid fracture, as described by CPT® Code 28531, is indicated for specific conditions related to the fracture of the sesamoid bones in the foot. The following indications are explicitly recognized for this procedure:

  • Sesamoid Fracture A fracture of the sesamoid bones located under the great toe joint, which may require surgical intervention due to displacement or instability.
  • Displaced Fracture When the fracture fragments are displaced, necessitating open reduction to restore proper anatomic alignment.
  • Failure of Conservative Treatment Situations where conservative management, such as closed treatment or immobilization, has not resulted in adequate healing or alignment.

2. Procedure

The procedure for the open treatment of a sesamoid fracture involves several critical steps, which are detailed as follows:

  • Step 1: Anesthesia Administration The procedure begins with the administration of appropriate anesthesia to ensure the patient is comfortable and pain-free during the surgical intervention.
  • Step 2: Surgical Exposure An incision is made over the site of the fracture to expose the fractured sesamoid bone. This step is crucial for accessing the fracture directly and allows for a clear view of the injury.
  • Step 3: Fracture Assessment Once the bone is exposed, the surgeon assesses the fracture to determine the best course of action, which may involve excising any fragmented bone pieces or attempting to realign the bone.
  • Step 4: Fracture Reduction If the fracture is displaced, the surgeon will manipulate the bone fragments back into their proper anatomic alignment. This step is essential for restoring function and stability to the joint.
  • Step 5: Internal Fixation (if necessary) In cases where stabilization is required, the surgeon may use internal fixation methods, such as pins or wires, to secure the fracture fragments in place, ensuring they remain aligned during the healing process.
  • Step 6: Closure After the fracture has been treated, the incision is closed using sutures or staples, and the area is dressed appropriately to promote healing.

3. Post-Procedure

Following the open treatment of a sesamoid fracture, patients can expect specific post-procedure care and considerations. It is essential to monitor the surgical site for any signs of infection or complications. Patients are typically advised to keep the foot elevated to reduce swelling and may be prescribed pain management medications as needed. A follow-up appointment is usually scheduled to assess healing and determine if further imaging, such as radiographs, is necessary to confirm proper alignment and healing of the fracture. Depending on the extent of the surgery and the individual’s recovery, weight-bearing activities may be restricted for a period, and the use of a cast or boot may be recommended to immobilize the foot during the healing process.

Short Descr TREAT SESAMOID BONE FRACTURE
Medium Descr OPEN TX SESAMOID FRACTURE W/WO INTERNAL FIXATION
Long Descr Open treatment of sesamoid fracture, with or without internal fixation
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) 1 - Statutory payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 2 - Co-surgeons permitted and no documentation required if the two- specialty requirement is met.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Hospital Part B services paid through a comprehensive APC
ASC Payment Indicator Surgical procedure on ASC list in CY 2007; payment based on OPPS relative payment weight.
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P3D - Major procedure, orthopedic - other
MUE 1
CCS Clinical Classification 147 - Treatment, fracture or dislocation of lower extremity (other than hip or femur)
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).
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.
AS Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery
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)
Date
Action
Notes
1993-01-01 Added First appearance in code book in 1993.
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