ICD-10-PCS Billable Code

0NSG04Z

Reposition Ethmoid Bone, Left to No Qualifier with Internal Fixation Device, Open Approach

Procedural Specifications

Clinical Axis Detail Definition
Section0 Medical and Surgical
Body SystemN Head and Facial Bones
OperationS Reposition
Body PartG Ethmoid Bone, Left
Approach0 Open
Device4 Internal Fixation Device
QualifierZ No Qualifier

Operation Definition

Moving to its normal location, or other suitable location, all or a portion of a body part

Procedure Overview

Repositioning procedures on the skull and facial bones move a bone, or a fragment of one, back to its correct anatomical alignment, or shift it to a new position that better restores function or appearance. Surgeons turn to this approach after trauma that has displaced facial or cranial bones, in cases of congenital jaw or skull malformation, or when growth abnormalities in children need gradual correction. Fixation hardware such as plates, screws, wires, or external distraction frames typically holds the bone in its new position while healing occurs.

Common examples include realigning a fractured mandible or zygoma, moving segments of the maxilla during orthognathic surgery to correct a bite or facial asymmetry, and craniofacial distraction to lengthen or reshape the skull in children with premature suture fusion. The goal is nearly always to restore normal chewing, breathing, speech, or the ability of the eyes and jaw to sit in proper alignment, along with a more typical facial appearance.

Recovery depends heavily on how much bone was moved and whether the correction happens in a single operation or gradually over weeks through a distraction device.

Anatomy & Axis Detail

Ethmoid Bone, Left

The left ethmoid bone occupies the space between the orbits, contributing to the medial orbital wall, nasal septum, and the cribriform plate that transmits olfactory nerve filaments into the cranial cavity. Repositioning is performed most often for nasoethmoidal or medial orbital wall fractures on the left side, where displaced fragments can alter orbital volume, disrupt the lacrimal drainage system, or, in more severe injuries, threaten the integrity of the anterior skull base. Its delicate, honeycombed structure makes fragment manipulation technically demanding, and surgeons typically work through endoscopic or periorbital access to realign the bone without further destabilizing adjacent thin walls. Careful reduction helps prevent enophthalmos and telecanthus that can result from unaddressed medial orbital wall displacement. Documentation should specify laterality and the involved substructure, such as the lamina papyracea or cribriform region.

Approach: Open

Open approach means the surgeon cuts through skin, mucous membrane, or other tissue layers to physically expose the target site to view before performing the procedure. It gives direct visualization and hands-on access, distinguishing it from Percutaneous approaches where instruments pass through a small puncture without exposing the site. Open is typical for procedures needing wide access, such as most laparotomies.

Device: Internal Fixation Device

Internal fixation device is the general value for hardware such as plates, screws, or rods placed within the body to stabilize bone or joint, used when a more specific configuration is not indicated. It stands in contrast to the named subtypes - Rigid Plate, Intramedullary, Sustained Compression, and Intramedullary Limb Lengthening - which specify how the hardware achieves stabilization.

Coding & Documentation

Coders assign a reposition code when the operative note describes moving a bone or fragment to a new spatial location, whether returning it to its original site or intentionally shifting it elsewhere, as with orthognathic osteotomies. The documentation needs to make clear that the bone itself was relocated, not simply exposed, stabilized, or trimmed. Look for terms like osteotomy with repositioning, realignment, or distraction, along with the specific facial or cranial bone involved and any device left behind for fixation.

The most frequent error is confusing reposition with fixation alone; if a fractured bone is simply reduced and plated without an intentional change in its spatial position beyond the reduction itself, some coders default to Reposition when the documentation may actually only support that root operation once true displacement correction is described. Another pitfall is failing to code the device value correctly when plates, screws, or an external distraction frame remain in place, since these devices matter for the qualifier and DRG assignment. Distraction osteogenesis cases are especially prone to sequencing errors when multiple activation adjustments occur over separate encounters.

Commonly Confused With

InsertionReposition is frequently confused with Reduction procedures coded elsewhere or with Insertion of fixation devices, since fracture care often involves several root operations at once.
ResectionOrthognathic cases are also sometimes mistaken for Resection, but Resection removes bone entirely rather than relocating it.