Cutting and Dissecting Instruments: Scalpels, Scissors, and Curettes

Cutting and Dissecting Instruments: Scalpels, Scissors, and Curettes

Cutting and dissecting instruments are among the most frequently used tools on any sterile field. As a surgical technologist, you are responsible for identifying each instrument correctly, understanding its intended use, and handling it in a way that protects both you and the patient. Misidentification or unsafe handling can cause serious injury; accuracy and discipline are non-negotiable.

Scalpel Handles and Blades

A scalpel consists of two parts: a handle and a blade. Handles are reusable; blades are single-use and disposable. The handle size determines which blade sizes fit it.

• Handle No. 3 accepts smaller blades: sizes 10, 11, 12, and 15. It is the most commonly used handle in general and plastic surgery.
• Handle No. 4 accepts larger blades: sizes 20, 21, 22, and 23. It is used when more pressure or a longer stroke is needed on thicker tissue.
• Handle No. 7 is a slender, pencil-shaped handle that also accepts No. 10, 11, and 15 blades. Its narrow profile improves visibility in confined or delicate areas.

Blade sizes and their primary uses:

| Blade | Shape | Common Use |

|-------|-------|------------|

| No. 10 | Large, rounded belly | General skin incisions, fascia |

| No. 11 | Pointed, triangular | Stab incisions, abscess drainage, vessel nicks |

| No. 15 | Small, curved belly | Precise or curved incisions, pediatric surgery, plastic/reconstructive work |

| No. 20 | Large rounded (No. 4 handle) | Deep incisions through thick tissue or muscle |

| No. 22 | Larger curved belly (No. 4 handle) | Skin and subcutaneous tissue in larger patients |

Safe Blade Mounting and Removal

Handling unprotected blades is one of the leading causes of sharps injuries in the OR. You must never use your fingers to mount or remove a blade.

To mount a blade: Use a needle driver held in your dominant hand. Grasp the blade on its dull spine (the thick, unsharpened back edge), not the cutting edge. Align the notch in the blade with the slot on the handle and slide it down until it clicks into place.

To remove a blade: Use the needle driver to grasp the dull spine of the blade near the handle. Lift slightly upward and then slide the blade forward off the handle, keeping the cutting edge directed away from your hands and body. Immediately place used blades into a puncture-resistant sharps container — never recap, bend, or leave a loose blade on the field.

Neutral Zone (Hands-Free) Technique

When passing a loaded scalpel to or from a surgeon, you must use the neutral zone, also called the hands-free technique. Place the loaded scalpel handle (blade down, handle toward the surgeon) in a designated area on the sterile field — typically a kidney basin or a small draped square. The surgeon picks it up without any hand-to-hand transfer. This technique eliminates the moment when both your hand and the surgeon's hand are simultaneously near the blade. AORN guidelines strongly support this practice as a standard sharps safety measure.

Scissors

Surgical scissors differ in blade length, curve, and tip design to match different tissue types.

• Mayo scissors have heavy, thick blades and are built for cutting dense, tough structures such as fascia, suture, and muscle. They come in straight (for suture cutting and surface work) and curved (for heavier tissue dissection) versions. Never use Mayo scissors on delicate tissue — the weight of the blades can crush fine structures.
• Metzenbaum scissors have long, slender shanks and short, lightweight blades. They are designed for blunt and sharp dissection of delicate tissue such as peritoneum, thin fascia planes, and areolar tissue. The long handle gives the surgeon fine control in deeper cavities.
• Iris scissors are small, lightweight scissors with pointed tips. Originally designed for ophthalmic surgery, they are now used in any procedure requiring precise cutting of fine, superficial tissue — plastic surgery, skin grafting, or delicate dissection near nerves and vessels.
• Bandage (or Lister) scissors have an angled blade with a blunt, probe-pointed lower jaw designed to slide safely under dressings or drapes without cutting skin. They are a wound-care and dressing-change instrument, not a surgical dissection tool.

Curettes

A curette is a spoon-shaped or ring-shaped instrument used to scrape or scoop tissue from a surface or cavity. Bone curettes have a cup-shaped, sharp-edged tip and are used to remove bone tissue, cartilage, or necrotic material — for example, during spinal surgery, orthopedic procedures, or removal of a bone cyst. Curettes come in varying sizes (often labeled by number or ring diameter); the surgeon will specify the size needed. Handle curettes carefully on the sterile field: the sharp cup edge can lacerate a glove or skin if grabbed carelessly.

Instrument Care on the Sterile Field

Keep all cutting instruments organized in a consistent location on your back table. Return instruments to the same spot after each use so you can hand them without looking away from the field. Wipe blades and scissor tips with a moist sponge (using an instrument — not your gloved finger) to remove blood and tissue, which can obscure cutting edges and reduce function. Count all sharps meticulously at every required count interval per facility protocol.

Why This Matters for the CST Exam and Your Career

The NBSTSA CST examination tests your ability to identify instruments and apply them correctly to clinical scenarios. Employers expect a practicing surgical technologist to handle sharps safely from day one. Mastering these fundamentals now builds the reflex-level accuracy that keeps operating room teams and patients safe.