A tissue retraction system (98) includes a dilator (106) and a first retractor member (102). The dilator is configured to be inserted into the tissue body toward a surgical site, and includes a dilator body (108) that is elongate along a longitudinal direction and sized to dilate the tissue body. The dilator includes at least one engagement member (156). The first retractor member includes a body (122) and at least one engagement member (154) that is configured to attach to the at least one engagement member of the dilator so as to removably attach the retractor member to the dilator body. The first retractor member and the dilator cooperate so as to define a passageway (142) when the first retractor member is attached to the dilator body. The tissue retraction system further includes a retractor assembly (300). The retraction assembly includes a retractor body (301)and at least a second retractor member (370) that is movably supported by the retractor body. The retractor body is configured to be attached to the first retractor member.
