Risk factors for dislocation after bipolar hemiarthroplasty: a retrospective case-control study of patients with CT data

Predicting Instability Risk Following Hemiarthroplasty for Femoral Neck Hip Fractures in Geriatric Patients

BACKGROUND

Although a rare complication, dislocation following hemiarthroplasty (HA) for a femoral neck hip fracture is associated with increased mortality, readmission, and possible revision surgery. To date many of the specific risk factors have been difficult to demonstrate. Patient factors, surgical factors, as well as morphological factors need to be assessed. Therefore, the purpose of this study was to elucidate the risk factors for dislocation of HA following femoral neck hip fractures in the geriatric population.

METHODS

This was a retrospective review of 270 patients who had hip fractures. Medical records between the years 2016 and 2022 informed binomial regression predictive models. The discriminative ability of variables in the final model and acetabular anteversion to predict dislocation was assessed with area under the curve (AUC) estimates.

RESULTS

Center edge angle (odds ratio 1.23), abduction angle (odds ratio 1.17), and depth width ratio (2.96e-11) were significant predictors of dislocation (P = .003, .028, and <.001, respectively). Center edge angle and depth width ratio (<44.1 ° and .298), respectively, were cut scores for risk. Dementia had a high discriminative of ability, as did men (AUC = 0.617, 0.558, respectively). Acetabular anteversion was not predictive of dislocation (P = .259) and theorized anteversion safe zones had poor discriminative ability with AUCs of 0.510 and 0.503, respectively.

CONCLUSIONS

Morphological factors related to hip dysplasia and a shallow acetabulum, which can be assessed with a radiograph alone, were found to be predictors of instability following HA in the elderly. Hemiarthroplasty implant design and manufacturer, and also acetabular version did not contribute to instability risk.

Comparative Effectiveness of Total Hip Arthroplasty and Hemiarthroplasty for Femoral Neck Fracture: A Propensity-Score-Matched Cohort Study

BACKGROUND

The optimal treatment of older patients with a displaced femoral neck fracture remains a controversial topic. This study aimed to compare clinical outcomes across a matched group of patients with a femoral neck fracture treated with either hemiarthroplasty or total hip arthroplasty (THA).

METHODS

Routinely collected health-care databases were linked to create a population-based cohort of 49,597 patients ≥60 years old from Ontario, Canada, who underwent hemiarthroplasty or THA for a femoral neck fracture between 2002 and 2017. A propensity-score-matched cohort was created using relevant and available predictors of treatment assignment and outcomes of interest. Clinical outcomes consisting of hip dislocation, revision surgery, hospital readmission, and death were compared in the matched cohort using survival analysis.

RESULTS

Over 99% of THA patients (4,612) were adequately matched 1:1 to hemiarthroplasty patients (total matched cohort = 9,224). Patients treated with THA were at higher risk for hip dislocation at 30 days and 1 and 2 years postoperatively (2-year risk, 1.8% for THA versus 0.8% for hemiarthroplasty; p < 0.001). There was no difference in the short-term (30-day) or long-term (up to 10-year) risk of revision surgery between treatment groups. There was no significant difference in the risk of 30-day hospital readmission between groups. The risk of death at 1 year and 2 years postoperatively was lower for patients treated with THA.

CONCLUSIONS

For patients with a hip fracture, shared decision-making should involve discussion of the potential higher risk of short-term hip dislocation after THA compared with hemiarthroplasty. The risk of revision surgery was similar between treatment groups at up to 10 years of follow-up.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Posterior acetabular wall morphology is an independent risk factor that affects the occurrence of acetabular wall fracture in patients with traumatic, posterior hip dislocation

PURPOSE

Smaller posterior acetabular walls have been shown to independently influence the risk for bipolar hip dislocation. We asked whether differences would also be observed in patients with traumatic posterior hip dislocation with and without posterior wall fractures.

METHODS

Between 2012 and 2020 we observed 67 traumatic posterior hip dislocations. Of these, 43 traumatic posterior hip dislocations in 41 patients met the inclusion criteria. Eighteen dislocations were excluded with an acetabular fracture other than posterior wall fracture and six dislocations had insufficient computed tomography (CT) data. The mean age was 41 ± 11 years, 32 males and nine females. We observed 26 traumatic hip dislocations with posterior wall fractures and 17 without. All patients underwent polytrauma CT scans and postoperative/postinterventional pelvic CT scans. On axial CT-scans, posterior wall determining angles were measured.

RESULTS

Patients with posterior wall fractures were not significantly older than patients without posterior wall fractures (42 ± 12 vs. 38 ± 10 years; p = 0.17). Patients without posterior wall fractures had significantly smaller posterior acetabular sector angles (84° ± 10°) than did patients with posterior wall fractures (105° ± 12°) (p < 0.01; OR 1.178). Likewise, the posterior wall angle was significantly smaller in patients without posterior wall fracture (62° ± 9°) than in those with posterior wall fractures (71° ± 8°) (p < 0.01; OR 1.141).

CONCLUSION

Both posterior acetabular sector angle and posterior wall angle are independent factors determining the posterior wall fracture morphology in patients with traumatic posterior hip dislocation. Age and the observed trauma mechanism did not differentiate between traumatic posterior hip dislocations with and without posterior wall fractures.

Patients with femoral neck fractures treated by bipolar hemiarthroplasty have superior to unipolar hip function and lower erosion rates and pain: a systematic review and meta-analysis of randomized controlled studies

PURPOSE

We assessed acetabular erosion, hip function, quality of life (QoL), pain, deep infection, mortality, re-operation and dislocation rates in patients with displaced femoral neck fractures (dFNFs) treated with unipolar versus bipolar hemiarthroplasty at different postoperative time points.

METHODS

Relevant Randomized Controlled Trials (RCTs) were identified, following comprehensive literature research in Medline, Cochrane Central and Scopus databases, from conception until August 31th, 2021 and analyzed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses.

RESULTS

Database research retrieved 120 studies; sixteen met eligibility criteria, providing 1813 (1814 hips) evaluable patients. Acetabular erosion was significantly higher for unipolar group at 6 and 12 months (p = 0.02 and p = 0.01 respectively). Patients in the bipolar group presented significantly better hip function at 12 and 24 months (p = 0.02 and p = 0.04 respectively). Postoperative pain was significantly less in the bipolar group at 12, 24 and 48 months (p = 0.01). No statistically significant differences were found regarding the postoperative rates of deep infection, mortality, re-operation and dislocation.

CONCLUSION

This study showed that patients with dFNFs treated with bipolar hemiarthroplasty have lower acetabular erosion rates at 6 and 12 months postoperatively, better hip function at 12 and 24 months, better QoL and less pain, when compared with unipolar. No statistically significant difference could be established regarding deep infection, mortality, re-operation and dislocation rates.

Hip fractures re-operation compared with death at two year in elderly patients: lowest risk of revision with dual mobility total hip arthroplasty than with bipolar hemiarthroplasty or internal fixation of Garden I and II

PURPOSE

This study determined at two year follow-up the lifetime risk of re-operation for elderly patients with hip fractures undergoing internal fixation, dual mobility total hip arthroplasty, or bipolar hemiarthroplasty, using death of the patient as a competing risk.

MATERIALS AND METHODS

With the hypothesis that arthroplasties may have less complications without increasing mortality even for Garden I and Garden II fractures, we retrospectively reviewed 317 hips with femoral neck fractures operated between January 2015 and August 2019. The mean age at time of surgical intervention was 82.4 years (range 65 to 105). Sixty patients presented a nondisplaced hip fracture (Garden I or II) treated by internal fixtion (I-F), and 257 were treated by hip arthroplasty: 118 dual mobility total hip arthroplasty (DM-THA) and 139 with a bipolar hemiarthroplaty (B-H). Demographics, surgical and complications data, and mortality were collected and compared for each group.

RESULTS

The overall mortality rate was 22.4% at two years, and similar (p = 0.98) in all groups, respectively 22%, 22%, and 23% for DM-THA, B-H, and I-F groups. With dual mobility THA, the cumulative incidence of re-operations for any reason was (lower (9%) than with internal fixation (22%) or bipolar hemiarthroplasties (19%).

CONCLUSION

Using a double mobility total prosthesis does not increase the post-operative mortality of the patients, nor does it increase their survival. But, reducing the risk of complications certainly improves their quality of life during the little time they have left .

Hip resection arthroplasty for acute femoral neck fractures in the non-ambulator

Objectives:

Hemiarthroplasty (HA) is the current standard of care for displaced femoral neck fractures (FNFs) in non-ambulators. Despite excellent outcomes, arthroplasty-specific risks remain, including dislocation, implant failure, periprosthetic fracture and infection, and fat embolization syndrome. To eliminate the possibility of these complications, should non-ambulatory patients with acute, native hip FNFs be treated with simple hip resection arthroplasty (HRA) instead of HA?

Design:

Retrospective case series.

Setting:

Large, urban level-1 trauma center.

Patients/Participants:

Five non-ambulatory patients (6 hips) with acute, native hip FNF underwent femoral head and neck resection. Also, the most recent 10 FNFs treated with HA were also identified for comparison purposes.

Intervention:

HRA was performed via a Smith-Peterson approach with an oscillating saw or osteotome to complete the fracture or perform a fresh neck cut.

Main Outcome Measurements:

Outcomes included postoperative vs preoperative VAS pain scores and narcotics usage, and return to baseline functional status (sit up in bed or a chair postoperatively). Procedure time for HRA was compared with the 10 most recent patients with FNF treated with HA.

Results:

HRA resulted in decreased postoperative vs preoperative VAS pain scores (7.7 vs 3.3, P = .002), and decreased operative times (59.2 minutes for HRA, 111.8 minutes for HA, P < .001). All HRA patients had immediate return of baseline function.

Conclusion:

HRA offers shorter operative times when compared with HA, decreased postoperative VAS pain scores, and immediate return to functional baseline status without possibility of arthroplasty-specific complications. HRA may be an acceptable treatment option for FNFs in the non-ambulator.

Level of evidence: IV

Surgical management of displaced femoral neck fractures in patients with dementia: a comparison in mortality between hemiarthroplasty and pins/screws

Introduction

Dementia is common in patients with hip fractures and is strongly associated with increased postoperative mortality. The choice of surgical intervention for displaced femoral neck fractures (dFNF) in patients with dementia has been a matter of debate. This study aims to investigate how short- and long-term mortality differs between those who have been operated with hemiarthroplasty or pins/screws.

Methods

All patients with dementia and dFNF, i.e., Garden III and IV, who underwent primary emergency hip fracture surgery, with either hemiarthroplasty or pins/screws, in Sweden between Jan 1, 2008 and Dec 31, 2017 were eligible for inclusion in the current study. Patients were divided into two groups based on the surgical intervention: hemiarthroplasty and pins/screws. The primary outcome of interest was 30-day postoperative mortality, and the secondary outcome was 1-year postoperative mortality. Poisson and Cox regression analyses were performed both before and after propensity score matching.

Results

A total of 9394 cases met the inclusion criteria; 84% received hemiarthroplasty and 16% received pins/screws. In the unmatched analysis, the adjusted incidence rate ratio (IRR) for 30-day postoperative mortality was not affected by the chosen surgical method (adj. IRR 0.96, CI 95% 0.83–1.12, p = 0.629). After propensity score matching, similar results were observed with no difference in 30-day postoperative mortality (adj. IRR 0.89, CI 95% 0.74–1.09, p = 0.286). There was a statistically significant decrease in the risk of 1-year postoperative mortality in the hemiarthroplasty group compared to the pins/screws group, both before and after propensity score matching.

Conclusion

This study could not demonstrate any difference in 30-day mortality in patients with dementia and dFNFs when comparing hemiarthroplasty with pins/screws. Patients that received hemiarthroplasties did, however, have a lower risk of 1-year postoperative mortality.