Single port access system

A surgical access system comprising:

• a retractor comprising:
• a proximal ring, wherein the proximal ring is configured to be disposed proximate an outer surface of a body wall of a patient;
• a retraction sheath coupled to the proximal ring, wherein the retraction sheath is configured to be disposed through an opening in the body wall of the patient;
• a distal ring coupled to the retraction sheath, wherein the distal ring is configured to be disposed proximate an inner surface of the body wall of the patient;
• and
• a sealing cap couplable to the proximal ring of the retractor;
• a trocar comprising:
• a fixation cannula comprising a cannula body comprising a proximal end and a distal end;
• a seal assembly coupled to the proximal end of the cannula body;
• a retainer radially extending from the distal end of the cannula body;
• wherein the trocar has an insertion configuration in which the cannula body is insertable into the sealing cap and disposed proximate an outer surface of the sealing cap and the trocar has a fixation configuration in which the cannula body captures the sealing cap between the proximal end of the cannula body and the retainer of the cannula body, thereby fixing the cannula to the sealing cap;
• wherein the retainer remains unchanged radially extending from the distal end of the cannula body in both the insertion configuration and in the fixation configuration.