Development of Needle Guide Unit Considering Buckling Bone-Perforation Control Strategy Based on Computed...

Area of Science:

• Medical Robotics
• Biomechanical Engineering
• Oncology

Background:

• Computed tomography (CT)-guided robotic systems aid needle insertion for vertebral metastatic carcinoma, but conventional needles risk bone fracture due to reaction forces.
• Percutaneous vertebroplasty, a treatment for brittle vertebrae caused by cancer or osteoporosis, requires precise needle insertion, which is challenging manually due to limited pathways.

Purpose of the Study:

• To develop and evaluate a multistage retractable needle guide unit designed to prevent buckling and crushing of ultrafine needles during CT-guided robotic insertion into vertebrae.
• To optimize needle guide design by analyzing the relationship between guide shape and buckling load, and identifying the plastic deformation point during bone drilling.

Main Methods:

• Developed a multistage retractable needle guide unit for 25-gauge ultrafine needles.
• Investigated needle buckling under load and plastic deformation during bone drilling.
• Conducted cadaveric evaluation tests on porcine vertebrae using the developed needle guide unit with a 25-gauge needle.

Main Results:

• The developed needle guide unit successfully prevented buckling and crushing of the 25-gauge needle tip during insertion into porcine vertebrae.
• Established critical parameters for needle guide design based on biomechanical analysis.

Conclusions:

• The multistage retractable needle guide unit is effective in enabling safe and accurate insertion of ultrafine needles in CT-guided robotic procedures.
• This technology holds significant clinical relevance for improving minimally invasive treatments like percutaneous vertebroplasty for vertebral bone metastases.