Osteochondroma Surgical Planning: When the Margin Is Barely Visible Yet the R0 Is Achieved

Preoperative planning based on CT and MRI to define the cutting planes

Guide positioning during surgery, supported by the preoperative 3D planning reference.

Tumor resection and specimen evaluation confirming an R0 margin.

In surgical oncology, certain cases stand out not because of their size or complexity alone, but because of the precision they demand. This recent case performed by Dr. Charlie Bouthors is a perfect example of such a scenario—one where millimeters truly mattered.

Osteochondroma Surgical Planning Leading to an R0 Resection

The patient presented with an osteochondroma positioned extremely close to the hip joint. The distal safe margin was reduced to the bare minimum, leaving almost no margin for approximation during the resection.

In such situations, the priority is twofold:

• achieve a complete resection,

• while remaining outside the joint to preserve its integrity.

Balancing these goals requires careful preparation and accurate intraoperative execution.

A Preoperative Plan Built Around Precision

To address these constraints, a highly detailed preoperative planning process was undertaken.

This planning defined three cutting planes, each adapted to the morphology of the tumor and the very limited working space available. Particular attention was given to the distal plane, where the margin was extremely narrow.

This thorough preparation guided the creation of a patient-specific resection guide, designed to provide:

• stable positioning,

• clear orientation of each cutting plane,

• and reliable intraoperative landmarks for the surgeon.

What the Planning and Guide Made Possible

By combining meticulous planning with a custom surgical guide, the team was able to achieve:

• strict control of the distal margin, despite minimal clearance,

• respect of the proximal margins, defined at 5 mm,

• a trajectory that stayed fully outside the joint, aligning with the surgical objective,

• and ultimately, an R0 resection, confirming the accuracy of the chosen approach.

  
  

A Noteworthy First Case in This Configuration

For a first case performed with this configuration, the result is particularly meaningful.

The procedure was carried out with exemplary precision and reflects the strength of the collaboration between the surgical team and the planning engineers involved.

Acknowledgments

Our sincere thanks to Dr. Bouthors and the operating room team for their trust and partnership throughout this case.