wordpress – calling widget using shortcode

I am using shortcode to call a widget. All is working fine but I want to pass some $instance(parameters) to the_widget. I am using $content to pass paramets to the_widget but I dont see any chnages after setting parameters.

Here is my shortcode function

add_shortcode('widget','widget');
function widget($atts) {
    // Configure defaults and extract the attributes into variables
    extract( shortcode_atts( 
        array( 
            'name'  => ''
        ), 
        $atts 
    ));
    $args = array(
        'before_widget' => '<div class="box widget">',
        'after_widget'  => '</div>',
        'before_title'  => '<div class="widget-title">',
        'after_title'   => '</div>',
    );

    ob_start();
    the_widget( $name, $content, $args ); 
    $output = ob_get_clean();

    return $output;    
}

And this is shortcode

[widget name="WP_Widget_Pages"]title=Pages&sortby=post_title[widget]

Please tell me what is the problem