Viipuri/Viborg belongs to the abolished parishes of the ceded region of Karelia. A village named Uuraa (other spellings Uura, Uurais, Uuras, Uuransaari, Uuraansaari etc) can as a matter of fact be found from the parish of Viipuri in the HisKi database http://www.genealogia.fi/hiski/d140az?en+A21
, in connection with the name Oikeroinen. I believe Oikeroinen and Uuraa(n saari) are the right names. Persons with the name Oikeroinen from Uuraa after 1875 are at least David Oikeroinen with first wife Maria Soininen (child Maria Mathilda in 1872) and second wife Sara Airikka (child David in 1875); Konsta(ntin) Oikeroinen and his wife Beata Riikonen (children between 1890-1899 were Olga, Agda, Lyyli Sofia, Karl Henrik).
The name Uuras (or Uuraansalmi) - Trångsund can be seen SW of Viipuri Viborg at for instance the map http://www.histdoc.net/uscha/c5.jpg
and Uuraan saari is just there. It is an island as the Finnish name saari tells.
Your query - how to trace descendants of this family - is much more difficult to answer, however.