Læknablaðið - 15.09.1996, Page 46

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LÆKNABLAÐIÐ 1996; 82
Fig. 6. The older wooden leg was made in 1910. The body weightfell outside the center ofthe wooden peg, which became skewed
and completely useless. a. viewéd from the side b. viewed from the front c. drawing from Fig. 6b.
Fig. 7. Signes ofwear in the older wooden leg. The drawing shows what happens when the body weightfalls outside thepeg. The
force makes thepeg unstable, itslants inward underthe weight andskews the wooden leg. The wooden peghas been worn almost
entirely on the outward side when walking ( ]) and presses with each step on the end ofthe inner support, which gradually wears
a trough in the side of the peg ( j j ). Due to the compression force the peg cracks lengthwise. Tlie tension causes the inner
support to break due to metal fatigue. It has been mended ( ] j j ).