Cancellous Screw 4 MM Partially Threaded [St. St.]

The Cancellous Screw 4 MM Partially Threaded [St. St.] is a component used within Orthopedic Internal Fixation systems. It is designed as a bone fixation screw with a nominal diameter of 4 mm and a Partial Thread Configuration for use in areas of Cancellous Bone, according to the approved indications and surgical technique.

The product design incorporates a Threaded Distal Section together with a Smooth / Unthreaded Shank toward the screw head. This geometry is characteristic of Partially Threaded Bone Screws and allows the screw to function as part of a fixation construct according to surgical requirements. When the partial thread is appropriately positioned and used according to the approved surgical technique, the design may be used as part of a Lag Screw Fixation / Interfragmentary Compression concept, provided that thread positioning and screw trajectory are suitable for the bone fragments and fixation technique.

According to the supplied product data, the screw is classified as St. St. – Stainless Steel and is available in six different lengths: 24, 26, 28, 30, 35, and 40 mm. This range allows the surgeon to select the appropriate Screw Length according to Bone Anatomy, Fixation Depth, Screw Trajectory, Fragment Thickness, and intraoperative measurements.

Each length carries an individual AMS Product Code, supporting organized Implant Identification, Surgical Set Preparation, Procurement, Inventory Management, and Stock Control.

What Is a 4 MM Partially Threaded Cancellous Screw?

A Cancellous Screw is an Orthopedic Bone Screw featuring thread geometry designed to achieve engagement within cancellous bone structures.

A Partially Threaded Design means that the screw thread does not extend along the entire length of the screw body, leaving a portion of the shaft unthreaded.

This design is used according to the approved Surgical Technique to achieve appropriate mechanical fixation and may be used as part of a Lag Screw Technique when suitable for the clinical case and fracture fixation method.

The primary specification of this product range is:

Nominal Screw Diameter: 4 MM

with six available length options.

Product Components and Design

1. Screw Head

The proximal head of the bone screw is designed to engage with the compatible insertion instrument and transmit Insertion Torque during fixation.

The exact Drive Interface type is not specified in the supplied product table.

2. Drive Recess

The screw head incorporates an Instrument Engagement Feature that allows use of the appropriate system-specific driver.

The exact type and dimensions of the drive interface should be confirmed using the approved Technical Datasheet.

3. Smooth / Unthreaded Shank

The unthreaded portion of the screw body distinguishes the Partially Threaded Screw from a fully threaded screw.

4. Cancellous Threaded Section

The distal threaded portion is designed to provide Thread Engagement within Cancellous Bone.

The supplied product table does not specify:

• Thread Pitch
• Major Diameter
• Core Diameter
• Thread Length

Therefore, no numerical values for these parameters should be published without official technical documentation.

5. Distal Tip

The distal end of the screw is designed to advance through the prepared bone pathway according to the approved surgical technique.

6. Stainless Steel Construction

The material is identified as:

[St. St.] – Stainless Steel

However, the exact Stainless Steel Grade or applicable ASTM / ISO Material Standard is not specified in the available product data.

Product Application

The Cancellous Screw 4 MM Partially Threaded is used within compatible Internal Bone Fixation applications requiring a cancellous bone screw.

According to the approved indications, it may be used as part of:

• Cancellous Bone Fixation
• Fracture Fragment Fixation
• Internal Fixation Constructs
• Bone Fragment Stabilization
• Lag Screw Fixation, when appropriate for the case and surgical technique

Selection of the appropriate screw depends on factors including:

• Bone Anatomy
• Bone Quality
• Fixation Site
• Fragment Thickness
• Screw Trajectory
• Required Screw Length
• Intraoperative Measurement

The appropriate Screw Length and method of use should be determined by a Qualified Orthopedic Surgeon in accordance with the approved IFU and Surgical Technique.

Key Benefits

4 MM Cancellous Screw Design

A nominal 4 mm diameter within the cancellous bone screw category for compatible orthopedic fixation applications.

Partially Threaded Configuration

Provides a design combining a Threaded Distal Portion with an Unthreaded Shank to accommodate specific fixation requirements.

Potential Lag Screw Application

The partial-thread geometry may be used within a Lag Screw Technique to support Interfragmentary Compression when applied according to appropriate surgical fixation principles.

Multiple Length Options

The product range is available in six lengths:

24 / 26 / 28 / 30 / 35 / 40 mm

providing multiple options according to bone depth and fixation trajectory.

Stainless Steel Construction

The product is classified as a Stainless Steel Bone Screw according to the supplied product data.

Clear Implant Identification

Each screw length carries an individual AMS Product Code, facilitating:

• Implant Identification
• Screw Selection
• Surgical Set Preparation
• Procurement
• Inventory Management
• Stock Control

Technical Specifications

Product Code	Product Description	Nominal Diameter	Total Length
AMS 104.274.024S	Cancellous Screw Part. Threaded [St. St.]	4 mm	24 mm
AMS 104.274.026S	Cancellous Screw Part. Threaded [St. St.]	4 mm	26 mm
AMS 104.274.028S	Cancellous Screw Part. Threaded [St. St.]	4 mm	28 mm
AMS 104.274.030S	Cancellous Screw Part. Threaded [St. St.]	4 mm	30 mm
AMS 104.274.035S	Cancellous Screw Part. Threaded [St. St.]	4 mm	35 mm
AMS 104.274.040S	Cancellous Screw Part. Threaded [St. St.]	4 mm	40 mm

Technical Overview

Product Name: Cancellous Screw 4 MM Partially Threaded [St. St.]
Product Type: Partially Threaded Cancellous Bone Screw
Product Category: Orthopedic Internal Fixation
Nominal Diameter: 4 mm
Thread Configuration: Partially Threaded
Material Category: Stainless Steel [St. St.]
Available Lengths: 24 / 26 / 28 / 30 / 35 / 40 mm
Length Range: 24–40 mm
Number of Configurations: 6
Primary Application: Cancellous Bone Fixation
Identification: Individual AMS Product Code for each length

Product Features

• 4 MM Cancellous Bone Screw
• Partially Threaded Design
• Manufactured from Stainless Steel [St. St.] according to the supplied product data
• Threaded Distal Section designed for engagement with cancellous bone
• Smooth / Unthreaded Shank as part of the partial-thread configuration
• May support Lag Screw Fixation Technique when used according to the appropriate indication and surgical technique
• Available in 6 Length Configurations
• Length Range: 24–40 mm
• Provides multiple options during Intraoperative Screw Selection
• Allows selection of screw length according to Bone Depth and Fixation Trajectory
• Designed for use within compatible Orthopedic Internal Fixation Constructs
• Individual Product Code for each length
• Facilitates Implant Identification and Surgical Set Preparation
• Supports Procurement, Inventory Management, and Stock Control