History e ajax, La pagina non cambia quando torno indietro

[cactua]

Salve, Sto provando a fare in modo che quando un utente clicca su un link di una lista numerata la pagina non cambia ma cambia semplicemente il contenuto di un div e all'url viene aggiunto un "?page=x" , fin qui nessun problema però mi sono accorto che quando clicco sul pulsante per tornare indietro l'url della pagina cambia ma il contenuto del div no.

Ho provato in tutti i modi possibili ma non riesco a risolvere, sotto vi posto il codice.

Spero che riusciate ad aiutarmi e grazie in anticipo =)

$("#page_nav #page_nav_center a").click(function(e) {                
                $("#footer").removeAttr("style");
                var max_number = <?php echo $numero_bottoni_episodi; ?>;
                var page_number = $(this).attr("href").split("=");
                var page_number = page_number[1];
                if(page_number == "first") {
                    var url = "?page=1";
                    page_number = 1;
                } else if(page_number == "last") {
                    var url = "?page="+max_number;
                    page_number = max_number;
                } else {
                    var url = "?page="+page_number;
                }
                window.history.pushState("changed", "Marco", url);
                document.cookie="pagenumber="+page_number;
                //$("#releases .release").animate({ opacity: 0.5 }, 300);
                $("body").animate({ scrollTop: 100 }, 500);
                //$("#releases .release").removeAttr("style");
                var number = $("#page_nav #page_nav_center a");
                number.removeAttr("class");
                var first = 1;
                var last = number.length;
                last = parseInt(last);
                last = last - 2;
                if(parseInt(page_number) <= 3) {
                    for (x=first; x<=last; x++) {
                        number.eq(x).html(x).attr("href","?page="+x);
                        number.eq(parseInt(page_number)).attr("class","active");
                    }
                } else if( parseInt(page_number) + 2 >= max_number ) {
                    var page_a = parseInt(max_number)-4;
                    var page_b = parseInt(max_number)-3;
                    var page_c = parseInt(max_number)-2;
                    var page_d = parseInt(max_number)-1;
                    var page_e = parseInt(max_number);
                    number.eq(1).html(page_a).attr("href","?page="+page_a);
                    number.eq(2).html(page_b).attr("href","?page="+page_b);
                    number.eq(3).html(page_c).attr("href","?page="+page_c);
                    number.eq(4).html(page_d).attr("href","?page="+page_d);
                    number.eq(5).html(page_e).attr("href","?page="+page_e);
                    if(page_a == page_number) {
                        number.eq(1).attr("class","active");
                    } else if(page_b == page_number) {
                        number.eq(2).attr("class","active");
                    } else if(page_c == page_number) {
                        number.eq(3).attr("class","active");
                    } else if(page_d == page_number) {
                        number.eq(4).attr("class","active");
                    } else if(page_e == page_number) {
                        number.eq(5).attr("class","active");
                    }
                } else {
                    var page_a = parseInt(page_number)-2;
                    var page_b = parseInt(page_number)-1;
                    var page_c = parseInt(page_number);
                    var page_d = parseInt(page_number)+1;
                    var page_e = parseInt(page_number)+2;
                    number.eq(1).html(page_a).attr("href","?page="+page_a);
                    number.eq(2).html(page_b).attr("href","?page="+page_b);
                    number.eq(3).html(page_c).attr("href","?page="+page_c).attr("class","active");
                    number.eq(4).html(page_d).attr("href","?page="+page_d);
                    number.eq(5).html(page_e).attr("href","?page="+page_e);
                    
                }


                $.ajax({ 
                    type: "POST",   
                       url: "refreshuscite.php",
                    data: { 
                        page: page_number
                    } ,
                       success : function(text) {
                           $("#releases").html(text);
                           $("#releases .release").mouseover(function() {
                            $(this).children("img").attr("src","image/anteprime/_hover.png");
                        })
                        $("#releases .release").mouseout(function() {
                            $(this).children("img").attr("src","image/spacer.png");
                        })
                        var footer = $("#footer").offset().top;
                        var finestra =  $(window).height();
                        finestra = finestra - 50;
                        if(footer < finestra) {
                            $("#footer").attr("style","position: absolute; bottom: 0;");
                        } else {
                        }
                       }
                });
                e.preventDefault();
            })