Dislocation of Total Hip Arthroplasty of Femoral Neck Fracture in the Elderly: A Narrative Review

Femoral neck fracture (FNF) is a common and devastating injury in the elderly population. The incidence of FNF is expected to increase in the future, particularly in the aging population. The displaced intracapsular FNF is replaced with a reconstruction prosthesis. These treatment options typically include hemiarthroplasty (HA) or total hip arthroplasty (THA). Dislocation after THA can be a significant complication, leading to increased hospital costs and patient dissatisfaction. This narrative review aims to investigate the potential risk factors for dislocation following THA after FNF. A systematic literature search was conducted, and 21 studies met the inclusion criteria. The studies included a total of 1703 patients who underwent THA after FNF. The majority of the patients were women, and the average age of participants was 76.2 years. The studies were primarily conducted by the orthopedic and traumatology departments. The surgical approach used for THA varied, with the anterior approach being associated with lower dislocation rates compared to the posterior approach. The analysis of surgical volume revealed that high-volume hospitals had lower dislocation rates compared to low-volume hospitals. Eight studies reported postoperative Harris Hip Scores (HHS), with higher HHS scores correlating with lower dislocation rates. Body mass index (BMI) was mentioned in 11 studies, and a normal BMI range was associated with lower dislocation rates compared to the overweight group. Rehabilitation protocols, particularly early initiation of physiotherapy, showed promising results in reducing dislocation rates. Additionally, the type of prosthesis used in the acetabulum was found to influence dislocation rates, with dual mobility cups demonstrating lower rates compared to single cups. In conclusion, several factors may contribute to the risk of dislocation following THA after FNF. These include the surgical approach, surgical volume, postoperative HHS scores, BMI, rehabilitation protocols, and the type of acetabular cup used. Further research is needed to better understand these risk factors and develop strategies to minimize dislocation rates and improve patient outcomes.