Case | Efficient Measurement for Artificial Joints

When human joints are damaged or diseased, stiffness and deformation often occur. If treatment through medication or other methods is not possible, surgical replacement with artificial joints is generally required to restore patients' daily lives.

Artificial joints mainly refer to prostheses for knees, hips, elbows, shoulders, fingers, and toes. Parameters such as size, 3D contour, and roughness are closely related to patients' health and thus require key evaluation. How to achieve efficient and quantitative quality management? In this issue, we bring you Mitutoyo's solution.

What are the challenges in artificial joint inspection?

01. Insufficient Accuracy

Artificial joints are mostly small in size and irregular in shape. At the same time, to match human anatomy, high machining accuracy is required during production. Traditional measuring tools, limited by accuracy, cannot accurately measure dimensions, let alone evaluate 3D contours.

02. Low Efficiency

Generally, measurement in the artificial joint field requires simultaneous evaluation of parameters such as size, 3D contour, and roughness. Most often, multiple measuring equipment are needed, resulting in cumbersome processes that consume significant human and material resources, leading to low efficiency.

03. Environmental Limitations

Temperature fluctuations can easily affect the stability of measurement results, causing defective products to pass through.

One Machine Solves Multiple Challenges

Using the CNC coordinate measuring machine CRYSTA-Apex V series, which combines high accuracy, high efficiency, and real-time temperature compensation function, can effectively solve the challenges faced when measuring artificial joints.

01. High Accuracy

Initial accuracy of 1.7 μm meets the measurement requirements of high-precision workpieces.

CRYSTA-Apex V series achieves an initial accuracy of 1.7 μm. Even high-precision workpieces can ensure accuracy; it also has higher repeatability.

02. High Efficiency

One instrument achieves 3D contour and dimensional measurement.

In addition to conventional dimensional inspection, when paired with the high-precision scanning probe SP25M, it can evaluate the complex curved surfaces of artificial joints. This allows one instrument to simultaneously perform 3D contour and dimensional measurements, greatly improving measurement efficiency.

03. Real-time Temperature Compensation

Ensures stability of measurement results, avoiding defective products.

Conventionally, coordinate measuring machines require a constant temperature and humidity environment to ensure measurement accuracy. However, the real-time temperature compensation function of the CRYSTA-Apex V series ensures accuracy even within a temperature range of 16°C to 26°C. By monitoring the temperature of the workpiece and the machine itself, and converting the measurement results to values at a standard temperature of 20°C for output, it guarantees the stability of measurement results.