This interesting and remarkable study presents previously unpublished data from a randomized controlled trial of treatment of femoral neck fractures with either total hip replacement or internal fixation. The investigators evaluated outcomes at eleven and seventeen years after enrollment, providing long-term data on fracture treatment that is rarely available, particularly in a randomized study design. The basic conclusion was that in active patients in the age group studied, total hip replacement is better. This conclusion would have been groundbreaking and controversial in the early 1990s, when this study began enrolling patients. This conclusion is now well known and accepted on the basis of studies published during the prolonged follow-up period of this study. However, the comparisons between the two treatment groups, performed well over a decade after the injury and treatment, provide a more definitive assessment of expected lifetime patient function and hip survival after the treatment of a femoral neck fracture.
Despite the early follow-up evidence that total hip replacement has fewer complications, there was reason for clinicians to be concerned about this treatment because of the possibility for an increased incidence of late failure as a result of loosening and periprosthetic fracture compared with successful internal fixation with a preserved native femoral head. This study addresses this concern by clearly showing that the high early failure rate after internal fixation is not completely offset by late failures after total hip replacement and provides further convincing evidence that total hip replacement is the best and most long-lasting option for the treatment of femoral neck fracture in patients over sixty-five years of age with excellent preexisting hip function.
Throughout the long follow-up period of this study, the chance of a major reoperation was 39% in the internal fixation group, compared with 9% in the total hip replacement group. The average hip score was higher and pain was less in the total hip replacement group throughout the duration of the study. The major reoperations in the internal fixation group occurred early in comparison with those in the total hip replacement group, which were performed in the later years of study, although the overall prevalence remained higher in the internal fixation group.
There are some weaknesses of the study design, including the randomization scheme and nonstringent assessment of reduction quality, with more procedures in the internal fixation group having been performed by junior surgeons. However, it seems unlikely that these flaws substantially altered the results. In addition, it is likely that the results of total hip replacement have improved more than those of internal fixation because of improvements in implant materials and design, soft-tissue techniques, and capsular repair as well as the use of larger heads and better bearing surfaces in the years since these patients were enrolled. It is important to realize that this study does not provide any direct information to allow these two procedures to be compared within other important groups of patients with femoral neck fractures. The authors screened eleven patients for every patient included in the study. This was a select group of elderly patients. In patients less than sixty-five years of age, the differences in results at long-term follow-up are likely to be less. This study demonstrates that the failures of internal fixation are mostly early and the failures of hip replacement are mostly late, suggesting that there might be more failures in the hip replacement group if the procedure was chosen for younger, more active patients. With longer life expectancy, the advantage of preservation of the native femoral head is clearly greater. Unfortunately, exact age and activity level cutoffs to aid decision-making are not possible. In addition, this study does not address patients with limited function because of greater prefracture morbidity who might benefit less from total hip arthroplasty. This study also does not include patients with nondisplaced or valgus-impacted fractures, for whom the preferred treatment remains internal fixation.
This study shows that, for patients with an age of sixty-five years or more who have a displaced femoral neck fracture and normal preinjury hip function, total hip replacement leads to better early function with less pain and a lower incidence of revision surgery in comparison with internal fixation and that, after long-term follow-up, these results are not negated by a higher late failure rate. These results, combined with other results reported in the literature, indicate that, in the patient group studied, total hip replacement is preferred over reduction and internal fixation for the treatment of a displaced femoral neck fracture.