On hospital day 5, she underwent a right THA via a Kocher-Langenbeck approach. The patient’s femoral head was found to be anterior and laterally adjacent to her ischial tuberosity with an indentation fracture. The sciatic nerve was identified and found to be intact. A metal-on-polyethylene Stryker Accolade femoral component and Trident acetabular shell were implanted, and a posterior capsular repair was performed (Figure 7).
The patient tolerated the procedure well, and her postoperative course was uneventful. She was discharged to a subacute rehabilitation facility on postoperative day 3. The patient returned for her 2-week postoperative visit ambulating without assistance. At her last follow-up visit, approximately 6 weeks after surgery, she was a functionally independent community ambulator. Phone conversations with her private orthopedist at 6 months confirmed continued ambulation without problems.
Discussion
This case report of a complication that occurred in our institution has resulted in a change in our protocol for treatment of geriatric anterior hip dislocations. Our institution is a level I trauma center, and traumatic hip dislocations are relatively common, occurring usually in young patients with high-energy trauma. Although somewhat controversial, it is generally assumed that the incidence of avascular necrosis of the femoral head after dislocation of the hip is correlated with the time interval from dislocation to reduction of the hip. Therefore, our protocol for hip dislocations of the hip in young trauma patients is urgent reduction in the ED under appropriate analgesia and muscle relaxation.
In this case report, the patient was older than 65 years with radiographic evidence of possible impingement and postsurgical evidence of impingement of the femoral head in the obturator foremen (Figures 1, 2, 8). In addition, the patient was significantly osteopenic radiographically. An attempted reduction in the ED resulted in FNF requiring THA (Figures 5, 6, 9). After discussion of this complication in our institution’s morbidity and mortality conference, we have developed a protocol for the geriatric patient (older than 65 years) with a traumatic hip dislocation. These patients will undergo attempted reduction under controlled analgesia and muscle relaxation in the operating room (OR) with an attending surgeon present, ideally, an attending surgeon comfortable with arthroplasty in a terminally cleaned OR room. Our institution’s surgical site infection rate after total joint arthroplasty has significantly decreased with improved patient selection and the use of terminally cleaned OR rooms. Because our policy is to perform closed reduction of dislocated hips in an urgent manner, if there is not a terminally clean room or an arthroplasty-trained attending orthopedic surgeon available, then informed consent with discussion of the possibility of fracture requiring a subsequent arthroplasty should be obtained from the patient before the attempted reduction.
After review of the available literature, we believe that this case highlights some of the important treatment principles when treating anterior hip dislocations in the ED. The relatively high incidence of indentation fractures of the femoral head with obturator dislocations puts these fractures at higher risk for possible impingement around the obturator ring. This impingement, coupled with preexisting osteopenia, can predispose these dislocations to FNF, if appropriate analgesia and sedation are not obtained and gentle reduction is not performed. In addition, while it may not be time- or cost-effective to perform closed reduction on every hip dislocation, we bring geriatric patients with radiographic osteopenia to the OR for more controlled reductions. In the informed consent discussion, the possibility of FNF is mentioned, and the patient and family are told that an elective total hip replacement will be performed if this complication occurs.
We consider the following to be risk factors for closed reductions of anterior hip dislocations: (1) preexisting osteopenia on plain films, (2) age greater than 65 years, and (3) radiographic femoral head impingement on the surrounding bony pelvis. We continue to consider closed reduction of both anterior and posterior hip dislocations as urgent (within 6 hours from time of dislocation). This case adds to the existing literature on the risk of FNF with closed reduction of obturator hip dislocations, and we hope that it will encourage further study into the safest and most cost-effective reduction protocol.