CONCLUSION
This case highlights the risks to overlook open occult female pelvic fractures in the perineal area. Detection becomes more feasible when features such as the ’free black air bubble sign’ and ’fracture blade sign’ on CT, and perineal wounds are identified. These signs help prevent missed diagnoses. Once the diagnosis is confirmed, the necessity of colostomy arises to prevent fecal contamination of the wound, thereby averting widespread infection and safeguarding the patient’s life. In instances of combined MLL injury, immediate considerations for puncture-negative pressure drainage or incision and drainage, along with pressure bandaging, should be explored to achieve optimal therapeutic outcomes.