I am using ADS1278 chip. Analog inputs to this chip have been routed in differential pair manner. The differential pair inputs trace length is maximum 9 inch within the board from the ribbon connector to ADC chip. So .. Does this cause a voltage drop... My input voltage level is plus and minus 2.5V differential going to ADC.
The minimum input impedance offered by the ADS1278 is 14kohm and if your traces were so long that they were ten ohms, the attenuation at DC would be 14,000/14,010 = 0.9993 or 6.2 milli decibels.
10 ohms of copper trace is many metres long BTW.
A 0.5mm wide trace on 1 oz copper is 9.71 ohms at 10m length. See this calculator