Total Hip Arthroplasty and Hemiarthroplasty: US National Trends in the Treatment of Femoral Neck Fractures
There is controversy regarding whether total hip arthroplasty (THA) or hemiarthroplasty (HA) is the treatment preferred for displaced intracapsular femoral neck fractures (FNFs). Using the US National Hospital Discharge Survey, we found that, of 12,757 patients admitted for FNF between 2001 and 2010, 4.6% underwent THA and 52.5% underwent HA. More of both procedures were performed over time. Mean age was higher for HA patients. Hospitalization duration and blood transfusion rates were higher for THA. There were region-based differences in frequency of THA and significant hospital-size-based differences in frequency of HA, possibly because of differences in regional training and subspecialist availability. In addition, a larger proportion of THA patients was covered by private insurance.
Discussion
The NHDS data showed a preference for HA over THA in the treatment of FNFs and suggested THA was favored for younger, healthier patients while HA was reserved for older patients with more comorbidities. Despite being younger and healthier, the THA group had higher transfusion rates and longer hospitalizations, possibly because of the increased complexity of THA procedures, which generally involve more operative time and increased blood loss. The resultant higher transfusion rate for THAs likely contributed to longer hospitalizations for FNFs. However, the THA and HA groups did not differ in their rates of DVT, PE, or mortality.
Multiple studies have noted no differences in mortality, infection, or general complications between THA and HA for FNF.8,10,11 THA patients have better functional outcomes, including Harris and Oxford hip scores and walking distance, but higher dislocation rates,8,10-12 and HA patients are at higher risk for reoperation because of progressive acetabular erosion.8,10,11
We noted an increase in use of both THA and HA for FNF over the study period (2001-2010). In a review of operative treatment for FNF by surgeons applying for the American Board of Orthopaedic Surgery certification between 1999 and 2011, Miller and colleagues13 found a similar increase in the THA rate over time, but decreases in the HA and internal fixation rates, with candidates in the “adult reconstruction” subspecialty showing a particularly strong trend toward THA use.
These findings reflect a general propensity toward femoral head replacement rather than preservation through open reduction and internal fixation (ORIF). Recent studies have found that ORIF carries a 39% to 43% rate of fixation failure and need for secondary revision, as well as risks of avascular necrosis, malunion, and nonunion.1,14-16 This need for secondary surgery makes ORIF ultimately less cost-effective than either THA or HA.16,17 Most authors would recommend arthroplasty for FNF in elderly patients with normal mental function1,16,18 and would reserve ORIF for young patients with good bone stock, joint space preservation, and reducible noncomminuted fractures.1,19
Our study results suggest that smaller hospitals (<100 beds) tend to have lower rates of HA (P < .01, significant) and THA (P = .10, not significant; Table), possibly because FNF patients who present to these hospitals may be referred elsewhere because of regional differences in the availability of orthopedic traumatologists and arthroplasty subspecialists. Surgeon volume affects postoperative outcomes and may play a role in referral patterns.20 Ames and colleagues20 found that HA performed for FNF by surgeons with high-volume THA experience (vs non-hip-arthroplasty surgeons) had lower rates of dislocation, superficial infection, and mortality.
Regional differences were significant for THA alone, with the highest THA rates in the South (5.2%) and the lowest in the West (3.3%; Figure 5). There were no clear regional trends for HA. Possible explanations include a propensity toward a more aggressive approach in these regions, increased regional prevalence of acetabular disease, regional surgeon preferences, and regional differences in patient characteristics (eg, increased prevalence of obesity in the South).21
