The Structure of Acupuncture Needles in Traditional Chinese Medicine

Materials of Acupuncture Needles

Acupuncture needles are made of metal. Currently, the most widely used in clinical practice are stainless steel needles, which possess high strength and toughness. The needle body is straight and smooth, resistant to high temperatures, rust, and corrosion from chemicals, making them durable and long-lasting.

There are also acupuncture needles made from other metals, such as gold and silver needles, which have better thermal and electrical conductivity than stainless steel needles, but their strength and toughness are inferior. Due to their high cost, they are rarely used in clinical settings. Earlier used copper, iron, and ordinary steel needles are prone to rust, have poor elasticity, toughness, and durability, and are no longer used in clinical practice.

Structure of Acupuncture Needles

The structure of acupuncture needles consists of five parts: the needle tip, needle body, needle root, needle handle, and needle tail.

Needle Tip: The sharp end of the needle body, also known as the needle point. Needle Body: The section between the needle tip and the needle handle, also referred to as the needle shaft. The length and thickness specifications of acupuncture needles mainly refer to this part. Needle Root: The part connecting the needle body to the needle handle. Needle Handle: The section from the needle root to the needle tail, wrapped in metal wire in a spiral shape for easy handling. Needle Tail: The end part of the needle handle, also known as the needle top. Typically wrapped with metal wire (steel or aluminum), it is cylindrical in shape.

Shapes of Acupuncture Needles

Based on the construction and shape of the needle handle and tail, acupuncture needles can be classified into:

Ring Handle Needles (also known as loop handle needles), where the needle handle is wrapped in silver-plated or oxidized metal wire to form a ring; Flower Handle Needles (also known as coiled dragon needles), where two metal wires are crossed and wrapped in a coiled dragon shape in the middle of the needle handle; Flat Handle Needles (also known as flat head needles), where the needle handle is also wrapped in metal wire, with a flat tail; Tube Handle Needles, where the needle handle is made of a metal sheet (stainless steel or aluminum) in a tubular shape. New types of steel handle needles are made of nickel-plated copper tubes resembling stainless steel. With advancements in technology, there are now plastic handle needles made from conductive plastic.

Specifications of Acupuncture Needles

The specifications of acupuncture needles are primarily based on the length and thickness of the needle body. (Table 1, Table 2)

Table 1 Length Specifications of Acupuncture Needles (in inches) 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 (in mm) 15 25 40 50 65 75 90 100 115 Table 2 Diameter Specifications of Acupuncture Needles Size 26 27 28 29 30 31 32 33 Diameter (cm) 0.45 0.42 0.38 0.34 0.32 0.30 0.28 0.26

The “Lingshu: Official Needles” states: “Each of the nine needles has its purpose, with varying lengths and sizes for different applications. If not used correctly, the illness cannot be alleviated.”

This indicates that different needles have their own characteristics and functions, and therefore, different conditions should use corresponding needle types. Clinically, the choice of needle length and thickness can be based on the patient’s constitution, body shape, age, condition, and the location of the acupoints.

Inspection of Acupuncture Needles

Acupuncture needles are tools for treating diseases, and they must be strictly inspected before and after each use. If any damage to the needle body is found, it should be immediately discarded and not reused to avoid accidents or affect the treatment’s efficacy. When selecting acupuncture needles, the following points should be noted:

Needle Tip: Should be sharp but not too pointed, rounded but not dull, resembling a “pine needle,” without hooks or curls.

Needle Body: Should be smooth, straight, round, uniform, strong, and elastic;

Needle Root: Should be firm, without peeling or scars;

Needle Handle: The metal wire should be evenly and securely wrapped, not loose, with appropriate length and thickness.

Maintenance and Storage of Acupuncture Needles

If using a needle tube, a dry cotton ball should be placed at the end from the needle tube to the needle tip (to prevent damage to the needle tip), then the needle should be inserted, covered, and sterilized under high pressure for future use.