Today, FTSE 100 index in London saw some change, when it resumed after four days of Christmas celebration.

This change made the Hips and knees maker Smith & Nephew to witness their biggest fall on the blue chip index as the investors felt fear at a recent warning from US regulators.

The share of London-based manufacturer of artificial knees and hips saw a fall of 5.5 percent which is the biggest intraday crash since July 2. This fall in the share price took their market value to 6 billion pounds ($9.2 billion).

FTSE 100 had closed at a figure over 6,000 last week, for the first time after June 2008. It is expecting a rally of 11% this year which is its best December after year 1993.

It happened after The Food and Drug Administration inspected the Smith & Nephew's facility in Tuttlingen, Germany and found the problems with the R3 Ceramic Acetabular Systems which made them to warn the implant maker who had failed to carry out certain required tests for a hip replacement product, and had subsequently failed to establish manufacturing procedures to address the problems.

This warning sent across a feeling of fright among the shareholders which resulted in the biggest fall of the Hips and knees maker’s share price.