Syntax problem PDO and bindvalue

So I am getting this SQL error: Error selecting photographs: SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''4'' at line 2 My code is: function updatephotos($dbh, $x) { echo $x['number'] . "<br />"; <<<<< this echo is 4 $sql = "SELECT * FROM photographs WHERE

              photo_filename LIKE '%2%' LIMIT 0, :q;";

$stmt = $dbh->prepare($sql); try {

        $stmt->bindValue( ':q', $x['number'], PDO::PARAM_INT );
        $stmt->execute();

      } catch (PDOException $e) {
            return 'Error selecting photographs: ' . $e->getMessage();
    }

while ( list( $id, $name, $alt, $caption) = $stmt->fetch(PDO::FETCH_NUM)) { echo $name . "<br />";

        }

return "test worked" ; } If I hard code the SQL as: $sql = "SELECT * FROM photographs WHERE

              photo_filename LIKE '%2%' LIMIT 0, 4";

all works well. Can anyone see what is wrong? How can I see the prepared SQL statement before it is executed? Thanks Stephen