Я решил проблему, выполнив код ниже.
function getTopTrackWalk($t, $k, $trackArr) {
if($t['track_code'] == $trackArr[0]) {
$trackDetails = variable_get('drf_admin_top_track_'. $k . '_news_list', array());
$trackArr[1][$trackArr[0]] = array('articles' =>
get_fav_details($trackDetails),
'trackName' => isset($t['title']) ? $t['title'] : "" );
}
}
array_walk($tracks, "getTopTrackWalk", array($track_id, &$return));