We can convert ‘Case Type’ select tag to radio button in online case form by using javascript.

<div style="display:block;">
<label for="category"></label>
<NLCATEGORY>
</NLCATEGORY>
</div>
$('form #category').each(function(i, select){
var $select = $(select);
$select.find('option').each(function(j, option){
var $option = $(option);
// Create a radio:
var $radio = $('<input type="radio" />');
// Set name and value:
$radio.attr('name', $select.attr('name')).attr('value', $option.val());
// Set checked if the option was selected
if ($option.attr('selected')) $radio.attr('checked', 'checked');
// Insert radio before select box:
$select.before($radio);
// Insert a label:
$select.before(
$("<label />").attr('for', $select.attr('name')).text($option.text())
);
// Insert a <br />:
$select.before("<br/>");
});
$select.remove();
});
