Abstract
A two-piece finger prosthesis has been proposed, manufactured from silane cross-linked polyethylene. Using a finger wear simulator the prosthesis was tested in a dilute bovine serum lubricant. Five tests were undertaken, totalling over 45 million cycles of wear testing. In each test, a statically loaded control prosthesis was included. In all tests it was found that the lubricant uptake of the test components exceeded that of the control components, consequently no gravimetric wear was measured. To investigate this result further, six cross-linked polyethylene prostheses were taken and soaked in the serum lubricant at 37 °C. Three of the prostheses were statically loaded and the other three were unloaded. These tests lasted for over one hundred and sixty days. It was found that the lubricant uptake of the unloaded control components was greater than that of the loaded components. The test with statically loaded prostheses was repeated, firstly with distilled water and then in lubricant heated to 30 °C and 40 °C. No significant difference in weight increase due to lubricant uptake at these two temperatures was found. The weight increase due to soaking in dilute bovine serum was several times that due to soaking in distilled water. (Journal of Applied Biomaterials & Biomechanics 2004; 2: 136–42)