Redesigned Surgical Laser Cuts Bone Deeper and Faster Than Before

Lasers are valued in surgery for their precision and non-contact cutting, reducing mechanical stress and minimizing microcracks. While widely used for soft tissue, their application in hard tissues such as bone has been limited. Traditional laser systems cut only 2 to 3 centimeters deep, which is insufficient for many orthopedic procedures, including joint implant placement. Researchers have now demonstrated a method that enables significantly deeper and faster bone cutting using a modified laser beam profile.

The breakthrough was achieved by researchers at the University of Basel (Basel, Switzerland) who altered the beam’s energy distribution profile instead of increasing laser energy, which could char bone and impair healing. Conventional surgical lasers use a Gaussian beam profile, where intensity is strongest at the center and gradually weakens toward the edges.

The researchers developed a “top hat” profile, which distributes energy more evenly across the beam’s surface before sharply dropping at the edges. This redesigned profile improves cutting efficiency by reducing energy loss along the walls of the incision. The team tested both laser profiles on bovine bone samples while cooling the tissue with compressed air and water to prevent thermal damage. The Gaussian beam achieved a cutting depth of approximately 2.6 centimeters, whereas the top hat beam reached 4.4 to 4.5 centimeters.

The study, published in Scientific Reports, showed that the even energy distribution prevented excessive absorption along the cut walls, allowing sufficient energy to reach the base of the incision. However, cutting speed remains a limitation: the laser removed about 0.4 cubic millimeters per second, compared to 11 cubic millimeters per second for a mechanical saw.

Although still slower than traditional surgical tools, the enhanced laser approaches clinically relevant cutting depths for orthopedic applications. Its ability to perform precise cuts without mechanical pressure could improve procedures such as the placement of custom-made, 3D-printed implants. Future work will focus on increasing cutting speed and adapting the system for use inside the human body, where protecting surrounding tissues will be critical.

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University of Basel