Total hip arthroplasty for post-firearm hip arthritis complicated by coloarticular fistula: A case report

Hip firearm injuries are rare injuries that could lead to serious complications, such as posttraumatic hip arthritis and coloarticular fistula. We report a case of a 25-year-old male who sustained a pelvic injury caused by a single bullet which led to a bilateral acetabular fracture, concomitant with a colon injury treated on an emergency basis by a diverting colostomy; acetabular fractures were treated conservatively by traction. After the patient recovered from the abdominal injury, he was presented with bilateral hip pain and limited motion; plain radiographs showed bilateral hip arthritis with proximal migration of the femoral head and bilateral acetabular defect classified as Paprosky type ⅢA. Reconstruction of the hips was performed using the same technique: impaction bone grafting for acetabular defect reconstruction and a reversed hybrid total hip arthroplasty (THA) 6 months apart. The patient presented with loosening of the left THA acetabular cup 3 years later, which was revised; then he presented with a discharging sinus from the left THA with suspicion of coloarticular fistula, which was confirmed using CT with contrast material. A temporary colostomy and fistula excision were performed, and a cement spacer was applied to the hip. After clearing the infection, a final revision THA for the left hip was performed. Treating post-firearm hip arthritis by THA is challenging, especially in the situation of neglected cases with the presence of an acetabular defect. Concomitant intestinal injury increases the risk of infection with the possibility of coloarticular fistula formation, which could present later. Working with a multidisciplinary team is paramount.