Scalpel

A scalpel, sometimes called a bistoury, is a small and extremely sharp bladed instrument.

These tools are essential for many precise tasks. Surgeons use them during medical operations to make clean cuts. They are also used for anatomical dissection, podiatry, and various handicrafts.

A specific type of scalpel known as a lancet features a double-edged blade. This design allows for small incisions or drainage punctures. Because they require such high precision, the design and material of a scalpel are very important.

Scalpel blades are manufactured from several different types of strong materials. Most are made of hardened and tempered steel, stainless steel, or high carbon steel. Some advanced versions use titanium, ceramic, diamond, or even obsidian.

The choice of material depends on the specific task. For example, steel blades cannot be used during an MRI. The strong magnets in an MRI machine would pull the steel blades toward them. This would cause dangerous movements and create image artifacts. To improve performance, some manufacturers add a zirconium nitride coating to help the edge stay sharp. Other blades use a polymer coating to increase lubricity, which helps the blade slide more easily during a cut.

In medical settings, scalpels are usually divided into two distinct parts: a handle and a blade.

Many handles are designed to be reusable, while the blades are often single-use. This is because each medical blade is typically used only once, or even for a single small cut. Handles are often called "B.P. handles." This name honors Charles Russell Bard and Morgan Parker, the founders of the Bard-Parker Company.

There are several common handle shapes. The #7 handle is long and rounded like a writing pen. The #5 handle is round and features a patterned surface to ensure a non-slip grip. The #3 and #4 handles are flatter in shape. Each blade is manufactured with a specific fitment size so it only fits one certain handle size.

There are many different blade shapes designed for specific surgical needs.

A #10 blade has a curved cutting edge and is often used for skin incisions. The #11 blade is triangular with a sharp point, making it good for precision cutting or stencil work. Podiatrists often use the #11P blade to debride hard skin like calluses. For more delicate work, the #15 blade is a smaller version of the #10. In cardiac surgery, the #15C blade is preferred because it has a downward angle. This allows surgeons to work more easily within the chest. Other blades, like the #20 or #22, are larger and used for general or orthopedic surgery.

Humans have used sharp cutting tools for thousands of years.

Obsidian scalpels found in a Bronze Age settlement in Turkey are older than 2100 BC. Ancient Egyptians also used sharpened obsidian for making incisions during embalming. By 500 BC, ancient Greeks were using tools very similar to modern scalpels. They used a tool called an amphismela, which means "on both sides" and "I cut."

In the 10th century, the Arab-Spanish surgeon Albucasis invented a retractable scalpel. Later, in 1915, Morgan Parker patented the two-piece scalpel design we recognize today. This was a major change because it allowed for more efficient tool use.

Safety is a critical concern when using these extremely sharp instruments.

In 2001, scalpel injuries accounted for 7 to 8 percent of all sharps injuries in medical settings. To protect workers, many hospitals now use safety scalpels. These come in two main styles: retractable blade types and retractable sheath types. Retractable blade models work much like a standard box-cutter. Sheath versions often provide a stronger ergonomic feel for the doctor.

Hospitals also use single-handed blade removers. These tools allow a person to take a blade off a handle without using their fingers. Using these safety methods can be up to five times safer than using a standard scalpel.

Beyond medicine, scalpels are used in many other fields. In the graphic arts, people use scalpels for model-making and detailed crafts.

These blades are often flat and straight so they can be used against a straightedge. Different shapes are also used for wood carving or cutting heavy fabrics and leather. Scientists even study how to make blades more efficient using technology. For instance, South African scientists found that ultrasound can make a blunt scalpel produce sharp cuts. This discovery might one day lead to new ways of cutting paper that save energy.