Yes. You can create Stored Procedure in PhpMyAdmin.
Here is one example that how you can write it. For that we have to first change the delimiter sign so that we can execute the query.
delimiter //
CREATE PROCEDURE Sample(IN userID INT, OUT userName VARCHAR(20))
BEGIN
SELECT UserName INTO userName FROM TblUsers WHERE UserID=userID;
END

Here is the PHP code. MYSQL: calling sp with out variables.

$rs = mysql_query( "CALL getCountry(1, @userName)" );
$rs = mysql_query( "SELECT @userName" );
while($row = mysql_fetch_assoc($rs))
{
echo $row['@userName'];
}