Dislocation of hemiarthroplasty after hip fracture is common and the risk is increased with posterior approach: result from a national cohort of 25,678 individuals in the Swedish Hip Arthroplasty Register

Clinical effectiveness of a modified muscle sparing posterior technique compared with a standard lateral approach in hip hemiarthroplasty for displaced intracapsular fractures (HemiSPAIRE): a multicenter, parallel-group, randomized controlled trial

Objectives

Assess the effect of a modified muscle sparing posterior approach; SPAIRE (Save Piriformis and Internus, Repairing Externus), in hip hemiarthroplasty for displaced intracapsular fractures on postoperative mobility and function compared with a standard lateral approach.

Design

Pragmatic, superiority, multicenter, parallel-group, randomized controlled trial (with internal pilot). Participants, ward staff, and research staff conducting postoperative assessments were blinded to allocation. A CTU allocated treatments centrally using computer-generated lists.

Setting

Six hospitals in Southwest England, recruiting November 25, 2019-April 25, 2022.

Participants

244 adults (≥60 years) requiring hip hemiarthroplasty (122 allocated to each approach). 90 and 85 participants allocated to SPAIRE and lateral, respectively, had primary outcome data within the prespecified data collection window.

Interventions

Surgery using SPAIRE or standard lateral approach. Follow-up 3 days and 120 days postoperation.

Main outcome measure

Oxford Hip Score (OHS), via telephone at 120 days. Secondary outcomes: function and mobility (3 days), pain (3 days, 120 days), discharge destination, length of hospital stay, complications and mortality (within 120 days), quality of life and place of residence (120 days).

Results

Participants' mean age was 84.6 years (SD 7.2); 168 (69%) were women. Primary outcome: little evidence of a difference in OHS at 120 days; adjusted mean difference (SPAIRE-lateral) -1.23 (95% CI -3.96 to 1.49, p=0.37). Secondary outcomes: indication of lower participant-reported pain at 3 days in SPAIRE arm; no differences between arms for remaining outcomes.

Conclusions

Participants' mobility and function are similar in the short term (3 days) and longer term (120 days), whether receiving the SPAIRE or lateral approach. Neither approach confers benefit over the other in terms of length of hospital stay, return to prefracture residence, survival within 120 days, or quality of life at 120 days. Participants receiving SPAIRE approach may experience less pain in the early postoperative period. Modifying the posterior approach in hip hemiarthroplasty to the SPAIRE approach gives equivalent patient outcomes to the lateral approach within 120 days.

Trial registration number

NCT04095611.

Comparison of conjoined tendon-preserving posterior approach and conventional posterolateral approach in hemiarthroplasty for femoral neck fracture in the elderly: A multicenter (TRON group) retrospective study

BACKGROUND

Femoral neck fractures (FNF) are one of the most common traumatic injuries in the elderly. The conjoined tendon-preserving posterior (CPP) approach was developed as a modification of the conventional posterolateral (PL) approach in hemiarthroplasty (HA) for displaced femoral neck fractures (FNF) to reduce postoperative dislocation. We hypothesized that the CPP approach would result in fewer dislocations and similar functional and radiographic outcomes compared to the PL approach.

PATIENTS AND METHODS

This was a retrospective multicenter (TRON group) study. We evaluated the rate of complications, and functional and radiographic outcomes for patients aged >65 years who underwent HA via the PL approach or the CPP approach from 2017 to 2019 and followed up for at least 24 months. To adjust for baseline differences between the groups, a propensity score-matching algorithm was used in a 1:1 ratio.

RESULTS

We identified 135 patients who underwent HA via the PL approach and 135 patients via the CPP approach. The mean follow-up period was 32.4 ± 14.0 months. The incidence of dislocation was 6 in 135 patients (4.4%) in the PL group and 0 in 135 patients (0%) in the CPP group, and there was significant difference (p = 0.04). Operation time was equivalent between the two groups (73.1 ± 30.4 vs. 71.8 ± 30.0 min; p = 0.72). The rate of varus insertion of stems in the PL group lower than that in the CPP group (19.3% vs. 33.3%; p = 0.01). Postoperative Parker's mobility score was similar between the two groups at 12 months follow-up (6.17 vs. 6.27; p = 0.81).

CONCLUSION

The CPP approach showed a significantly lower dislocation rate, similar functional outcome and more varus stem insertions compared with the PL approach in this retrospective study.

Replacing hip precautions after hemiarthroplasty with a pose avoidance protocol

AIMS

After hip arthroplasty surgery, hip precautions are often implemented to minimise the risk of dislocation, although existing evidence does not support their effectiveness. At our institution, we replaced post-operative precautions with a novel pose avoidance protocol in patients undergoing hip hemiarthroplasty for neck of femur fracture. The objectives of our study were to validate this new protocol by assessing the incidence of dislocation before and after its introduction and evaluating its impact on the length of hospital stay.

METHODS

Between 20th September 2021 and 19th March 2023, 200 patients underwent 203 hip hemiarthroplasties. Hip precautions were replaced with the new pose avoidance protocol on 20th June 2022. Data were retrospectively collected and included patient demographics, Abbreviated Mental Test Score, American Society of Anaesthesiologists grade, surgical approach, prosthesis, dislocation, and mortality.

RESULTS

The incidence of dislocation within 90 days after hip hemiarthroplasty decreased from seven out of 98 cases (7.1%) before 20th June 2022 to one out of 105 cases (1.0%), p-value 0.030. However, there was no significant difference in the length of stay, with a median (interquartile range) of 19 (10 - 29) days before 20th June 2022, and 16 (11 - 22) days thereafter, p-value 0.242. A multivariate logistic regression confirmed the pose avoidance protocol and the anterolateral approach to be independent negative predictors of dislocation, p-value 0.030 (Odds Ratio [OR] 0.077) and p-value 0.005 (OR 0.022), respectively.

CONCLUSIONS

Hip precautions are unnecessary and potentially detrimental to patient outcomes following hemiarthroplasty. Replacing these precautions with our new pose avoidance protocol may have led to a significant reduction in dislocation rates and saved on the cost of adaptive equipment. We advocate for the anterolateral over the posterior approach in hip hemiarthroplasty to further mitigate the risk of dislocation.

LEVEL OF EVIDENCE

IV.

Bipolar hip arthroplasty using conjoined tendon preserving posterior lateral approach in treatment of displaced femoral neck fractures

BACKGROUND

Hip fractures account for 23.8% of all fractures in patients over the age of 75 years. More than half of these patients are older than 80 years. Bipolar hemiarthroplasty (BHA) was established as an effective management option for these patients. Various approaches can be used for the BHA procedure. However, there is a high risk of postoperative dislocation. The conjoined tendon-preserving posterior (CPP) lateral approach was introduced to reduce postoperative dislocation rates.

AIM

To evaluate the effectiveness and safety of the CPP lateral approach for BHA in elderly patients.

METHODS

We retrospectively analyzed medical data from 80 patients with displaced femoral neck fractures who underwent BHA. The patients were followed up for at least 1 year. Among the 80 patients, 57 (71.3%) were female. The time to operation averaged 2.3 d (range: 1-5 d). The mean age was 80.5 years (range: 67-90 years), and the mean body mass index was 24.9 kg/m2 (range: 17-36 kg/m2). According to the Garden classification, 42.5% of patients were type Ⅲ and 57.5% of patients were type Ⅳ. Uncemented bipolar hip prostheses were used for all patients. Torn conjoined tendons, dislocations, and adverse complications during and after surgery were recorded.

RESULTS

The mean postoperative follow-up time was 15.3 months (range: 12-18 months). The average surgery time was 52 min (range: 40-70 min) with an average blood loss of 120 mL (range: 80-320 mL). The transfusion rate was 10% (8 of 80 patients). The gemellus inferior was torn in 4 patients (5%), while it was difficult to identify in 2 patients (2.5%) during surgery. The posterior capsule was punctured by the fractured femoral neck in 3 patients, but the conjoined tendon and the piriformis tendon remained intact. No patients had stem varus greater than 3 degrees or femoral fracture. There were no patients with stem subsidence more than 5 mm at the last follow-up. No postoperative dislocations were observed throughout the follow-up period. No significance was found between preoperative and postoperative mean Health Service System scores (87.30 ± 2.98 vs 86.10 ± 6.10, t = 1.89, P = 0.063).

CONCLUSION

The CPP lateral approach can effectively reduce the incidence of postoperative dislocation without increasing perioperative complications. For surgeons familiar with the posterior lateral approach, there is no need for additional surgical instruments, and it does not increase surgical difficulty.

Incidence of dislocation and associated risk factors in patients with a femoral neck fracture operated with an uncemented hemiarthroplasty

BACKGROUND

Several factors might be associated with risk of dislocating following uncemented hemiarthroplasty (HA) due to femoral neck fracture (FNF). Current evidence is limited with great variance in reported incidence of dislocation (1-15%). Aim of this study was to identify the cumulative incidence of first-time dislocation following HA and to identify the associated risk factors.

METHOD

We performed a retrospective cohort study of patients receiving an HA (BFX Biomet stem, posterior approach) at Copenhagen University Hospital, Bispebjerg, in 2010-2016. Patients were followed until death or end of study (dec 2018). Dislocation was identified by code extraction from the Danish National Patient Registry. Variables included in the multivariate model were defined pre-analysis to include: age, sex and variables with a p-value < 0.1 in univariate analysis. A regression model was fitted for 90 days dislocation as the assumption of proportional hazard rate (HR) was not met here after.

RESULTS

We identified 772 stems (some patients occurred with both right and left hip) and 58 stems suffered 90 dislocations during the observation period, resulting in a 7% (CI 5-9) incidence of dislocation 90 days after index surgery. 55 of the 58 stems (95%) experienced the first dislocation within 90 days after surgery. Only absence of dementia was identified as an independent protective factor in the cause-specific model (HR 0.46 (CI 0.23-0.89)) resulting in a 2.4-fold cumulative risk of experiencing a dislocation in case of dementia. Several other variables such as age, sex, various medical conditions, surgery delay and surgical experience were eliminated as statistical risk factors. We found a decrease in survival probability for patients who experienced a dislocation during follow-up.

CONCLUSIONS

The incidence of first-time dislocation of HA (BFX Biomet stem, posterior approach) in patients with a hip fracture is found to be 7% 90 days after surgery. Due to the non-existing attribution bias, we claim it to be the true incidence. Dementia was among several variables identified as the only risk factor for dislocation. In perspective, we may consider treating patients with dementia by other methods than HA e.g., HA with cement or with a more constrained solution. Also, a surgical approach that reduce the risk of dislocation should be considered.

Unipolar Hemiarthroplasty, Bipolar Hemiarthroplasty, or Total Hip Arthroplasty for Hip Fracture in Older Individuals

BACKGROUND

Practice patterns regarding the use of unipolar hemiarthroplasty, bipolar hemiarthroplasty, and total hip arthroplasty (THA) for femoral neck fractures in older patients vary widely. This is due in part to limited data stipulating the specific circumstances under which each form of arthroplasty provides the most predictable outcome. The purpose of this study was to investigate the patient characteristics for which unipolar hemiarthroplasty, bipolar hemiarthroplasty, or THA might be preferable due to a lower risk of all-cause revision.

METHODS

A U.S. health-care system's hip fracture registry was used to identify patients ≥60 years old who underwent unipolar hemiarthroplasty, bipolar hemiarthroplasty, or THA for hip fracture from 2009 through 2021. Unipolar and bipolar hemiarthroplasty were compared with THA within patient subgroups defined by age (60 to 79 versus ≥80 years) and American Society of Anesthesiologists (ASA) classification (I or II versus III); patients with an ASA classification of IV or higher were excluded. Multivariable Cox proportional hazard regression analysis was used to evaluate all-cause revision risk while adjusting for confounders, with mortality considered as a competing risk.

RESULTS

There were 14,277 patients in the final sample (median age, 82 years; 70% female; 80% White; 69% with an ASA classification of III; median follow-up, 2.7 years), and the procedures included 7,587 unipolar hemiarthroplasties, 5,479 bipolar hemiarthroplasties, and 1,211 THAs. In the multivariable analysis of all patients, both unipolar (hazard ratio [HR] = 2.15, 95% confidence interval [CI] = 1.48 to 3.12; p < 0.001) and bipolar (HR = 1.92, 95% CI = 1.31 to 2.80; p < 0.001) hemiarthroplasty had higher revision risks than THA. In the age-stratified multivariable analysis of patients aged 60 to 79 years, both unipolar (HR = 2.17, 95% CI = 1.42 to 3.34; p = 0.004) and bipolar (HR = 1.69, 95% CI = 1.08 to 2.65; p = 0.022) hemiarthroplasty also had higher revision risks than THA. In the ASA-stratified multivariable analysis, patients with an ASA classification of I or II had a higher revision risk after either unipolar (HR = 3.52, 95% CI = 1.87 to 6.64; p < 0.001) or bipolar (HR = 2.31, 95% CI = 1.19 to 4.49; p = 0.013) hemiarthroplasty than after THA. No difference in revision risk between either of the hemiarthroplasties and THA was observed among patients with an age of ≥80 years or those with an ASA classification of III.

CONCLUSIONS

In this study of hip fractures in older patients, THA was associated with a lower risk of all-cause revision compared with unipolar and bipolar hemiarthroplasty among patients who were 60 to 79 years old and those who had an ASA classification of I or II.

LEVEL OF EVIDENCE

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

Revision Risk of Unipolar and Bipolar Hemiarthroplasties in the Dutch Arthroplasty Register

BACKGROUND

Hemiarthroplasty (HA) for hip fractures can be performed with a unipolar or bipolar head. We describe the use of unipolar and bipolar HA after a hip fracture in the Netherlands and determined revision rates and risk factors.

METHODS

All HAs for an acute hip fracture registered in the Dutch Arthroplasty Register (LROI) during 2007 to 2021 were included; 44,127(88%) unipolar and 6,013(12%) bipolar HAs. Competing risk survival analyses were performed with revision for any reason as the endpoint. Multivariable Cox regression analyses were performed adjusting for patient and surgery-related factors.

RESULTS

The 1-year, 5-year, and 10-year revision rates were comparable for unipolar and bipolar HA. Cox regression analysis showed a hazard ratio of 1.2 (95% confidence interval (CI) 1.0 to 1.4)) after adjustment for confounders for bipolar heads. In cases of a cemented stem, the 1-year cumulative incidence of revision was lower (1.5% (CI 1.4 to 1.7%) compared to uncemented stems (2.4% (CI 2.1 to 2.7%); uncemented stems showed higher risks for revision after adjustment compared to cemented stems (hazard ratio 1.4 (CI 1.2 to 1.5)). The anterior, antero-lateral, and straight-lateral approach showed lower risk for revision compared to the postero-lateral approach.

CONCLUSION

The revision rate for bipolar HA and unipolar HA was comparable. However, after adjustment for potential confounders the risk for revision showed an estimated 20% increased revision risk for bipolar heads, although not statistically significant. For both head types, the risk for revision was significantly higher when an uncemented stem was chosen or the postero-lateral approach was used.

Dementia and Hip Fractures: A Comprehensive Review of Management Approaches

» The elderly population is the fastest growing demographic, and the number of dementia cases in the United States is expected to double to 10 million by 2050.» Patients with dementia are at 3× higher risk of hip fractures and have higher morbidity and mortality after hip fractures.» Hip fracture patients with dementia benefit from early analgesia and timely surgical fixation of fracture.» Early and intensive inpatient rehabilitation is associated with improved postoperative outcomes in patients with dementia.» Coordination of care within a "orthogeriatric" team decreases mortality, and fracture liaison services show potential for improving long-term outcomes in hip fracture patients with dementia.

Complications and early recovery following hip hemiarthroplasty through the direct anterior approach: a systematic review and meta-analysis

PURPOSE

Minimizing complications is an important focus in hip hemiarthroplasty (HHA) for femoral neck fracture (FNF) patients given the associated high morbidity and mortality rates. This systematic review and meta-analysis aimed to compare the clinical and functional outcomes associated with the direct anterior approach (DAA) compared to other surgical approaches used for HHA.

METHODS

Studies evaluating HHA-treated FNFs using the DAA were compared through meta-analysis to all other surgical approaches combined and as distinct subgroups. Outcomes included overall complication rate, mortality rate, dislocation rate, reoperation rate, periprosthetic fracture rate, infection rate, length of stay (LOS), mobility, perioperative blood loss, operative time, and postoperative pain.

RESULTS

Nineteen studies met the inclusion criteria, totaling 2,018 HHAs. DAA significantly reduced the overall complication rate (odds ratio (OR) = 0.73, 95% confidence interval (CI) 0.57 to 0.94, p = 0.01), dislocation rate (OR = 0.34, 95% CI 0.15 to 0.77, p = 0.01), and LOS (mean difference (MD) = -1.31 days, 95% CI  - 2.12 to  - 0.50, p = 0.002). Findings from studies that were not appropriate for meta-analysis were qualitatively summarized and suggested improved mobility and reduced postoperative pain with the DAA. Significant differences were not detected in any of the remaining outcomes.

CONCLUSION

The DAA HHA appears to be safer, reduces hospital stay, and may improve early functional recovery. This article supports the DAA HHA as a safe option for the management of displaced intracapsular FNFs.

Hemiarthroplasty Versus Total Hip Arthroplasty for Femoral Neck Fracture in Elderly Patients: Twelve-Month Risk of Revision and Dislocation in an Instrumental Variable Analysis of Medicare Data

BACKGROUND

There is practice variation in the selection of a total hip arthroplasty (THA) or a hemiarthroplasty (HA) for the treatment of displaced femoral neck fractures in elderly patients. Large data sets are needed to compare the rates of rare complications following these procedures. We sought to examine the relationship between surgery type and secondary hip surgery (revision or conversion arthroplasty) at 12 months following the index arthroplasty, and that between surgery type and dislocation at 12 months, among elderly Medicare beneficiaries who underwent THA or HA for a femoral neck fracture, taking into account the potential for selection bias.

METHODS

We performed a population-based, retrospective study of elderly (>65 years of age) Medicare beneficiaries who underwent THA or HA following a femoral neck fracture. Two-stage, instrumental variable regression models were applied to nationally representative Medicare medical claims data from 2017 to 2019.

RESULTS

Of the 61,695 elderly patients who met the inclusion criteria, of whom 74.1% were female and 92.2% were non-Hispanic White, 10,268 patients (16.6%) underwent THA and 51,427 (83.4%) underwent HA. The findings from the multivariable, instrumental variable analyses indicated that treatment of displaced femoral neck fractures with THA was associated with a significantly higher risk of dislocation at 12 months compared with treatment with HA (2.9% for the THA group versus 1.9% for the HA group; p = 0.001). There was no significant difference in the likelihood of 12-month revision/conversion between THA and HA.

CONCLUSIONS

The use of THA to treat femoral neck fractures in elderly patients is associated with a significantly higher risk of 12-month dislocation, as compared with the use of HA, although the difference may not be clinically important. A low overall rate of dislocation was found in both groups. The risk of revision/conversion at 12 months did not differ between the groups.

LEVEL OF EVIDENCE

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

Outcomes Following Hemiarthroplasty for Femoral Neck Fracture in Patients Who Have Hemiparesis

BACKGROUND

Hemiparesis increases the risk of femoral neck fracture (FNF) in the elderly, which frequently necessitates hemiarthroplasty. There are limited reports on the outcomes of hemiarthroplasty in patients who have hemiparesis. The purpose of this study was to evaluate hemiparesis as a potential risk factor for medical and surgical complications following hemiarthroplasty.

METHODS

Hemiparetic patients who have concomitant FNF and underwent hemiarthroplasty with at least 2 years of follow-up were identified using a national insurance database. A 10:1 matched control cohort of patients who did not have hemiparesis was created for comparison. There were 1,340 patients who have and 12,988 patients who did not have hemiparesis undergoing hemiarthroplasty for FNF. Multivariate logistic regression analyses were used to evaluate rates of medical and surgical complications between the 2 cohorts.

RESULTS

Aside from increased rates of medical complications including cerebrovascular accident (P < .001), urinary tract infection (P = .020), sepsis (P = .002), and myocardial infarction (P < .001), patients who have hemiparesis also experienced higher rates of dislocation within 1 and 2 years (Odds Ratio (OR) 1.54, P = .009; OR 1.52, P = .010). Hemiparesis was not associated with higher risk of wound complications, periprosthetic joint infection, aseptic loosening, and periprosthetic fracture, but was associated with higher incidence of 90-day ED-visits (OR 1.16, P = .031) and 90-day readmission (OR 1.32, P < .001).

CONCLUSION

While patients who have hemiparesis do not have increased risk of implant-related complications other than dislocation, they are at increased risk of developing medical complications following hemiarthroplasty for FNF.

Functional Outcomes of Anterior-Based Muscle Sparing Approach Compared to Direct Lateral Approach for Total HIP Arthroplasty Following Acute Femoral Neck Fractures

Introduction

Total hip arthroplasty (THA) performed for femoral neck fractures (FNFs) is becoming a more frequent treatment in the active elderly population. Since there is limited research available presenting clinical outcomes after THA using the anterior-based muscle sparing (ABMS) approach, the aim of this study was to compare this surgical approach to the direct lateral (DL) approach in patients treated by THA for FNFs.

Materials and Methods

We retrospectively reviewed the data prospectively collected as a part of our "Hip Fracture Unit" and included 163 patients who underwent THA from January 2016 to January 2019 for acute displaced FNFs.

Results

A total of 132 patients who completed a minimum 2-years follow up (69 in the ABMS group and 63 in DL group) were included. The ABMS group demonstrated significantly shorter time to reach milestone for hospital discharge (1.5 Days vs 2.1 days, P = .018), while no statistically significant differences were detected in peri-operative complications. At 3 months, the timed up and go test, the Harris Hip Score (HHS) and the Oxford ip Score (OHS) were significantly better (P = .024, .032 and .034, respectively) in the ABMS group compared to the DL group. No differences were found in functional outcomes (HHS and OHS) nor in complication rate at 6, 12 and 24 months.

Discussion

This is one of the first studies to analyze functional results of THA performed for FNFs through an ABMS approach. Results are in line with those already present in the Literature.

Conclusion

ABMS approach allows earlier mobilization and better early functional outcomes, compared to DL approach, in patients undergoing THA for acute displaced FNF. No differences are found after 6 months in functional results and complications rate.

A piriformis-preserving posterior approach reduces dislocation rate of the hemiarthroplasty in patients with femoral neck fracture

INTRODUCTION

The posterior approach (PA) for hemiarthroplasty (HA) in patients with femoral neck fracture (FFN) has a high risk of dislocation; however, by preserving the piriformis muscle, the dislocation rate could be lowered considerably. The aim of this study was to compare the surgical complications of the piriformis-preserving posterior approach (PPPA) and the PA in patients with FNF treated with HA.

METHODS

On 1 January 2019, the PPPA was introduced at two hospitals as the new treatment standard. The sample size was calculated based on a 5 percentage point dislocation reduction and 25% censoring; a sample of 264 patients per group was determined. An approximately 2-year inclusion period with 1-year follow-up was estimated, including a historical cohort from 2 years before the PPPA introduction. Data were retrieved from health care records and X-ray images from the hospitals' administrative databases. Relative risk (RR) and 95% confidence intervals were calculated using Cox regression and adjusted for age, sex, comorbidity, smoking, surgeon experience and implant type.

RESULTS

There were 527 patients included in the study, of which 72% were women and 43% were above 85 years old. There were no baseline differences between the PPPA and PA groups in sex, age, comorbidity, body mass index, smoking, alcohol, mobility, length of surgery, blood loss or implant positioning, but there were differences in 30-day mortality, surgeon experience and implant type. The dislocation rate reduced from 11.6% in the PA group to 4.7% in the PPPA group (p = 0.004), with an RR of 2.5 (1.2; 5.1). The reoperation rate reduced from 6.8% with the PA to 3.3% with the PPPA (p = 0.022), with an RR of 2.1 (0.9; 5.2), and total surgery-related complications reduced from 14.7% with the PA to 6.9% with the PPPA (p = 0.003), with an RR of 2.4 (1.3; 4.4).

INTERPRETATION

Changing from PA to PPPA in patients with FNF treated with HA resulted in a more than 50% reduction in dislocation and reoperation rates. This approach was easily introduced and may enable further lowering of dislocation rates through the sparing of all short external rotators.

Comparison of Dislocation and Outcome Between Piriformis-Sparing and Conventional Posterior Approach After Bipolar Hemiarthroplasty for Femoral Neck Fracture in Patients Over 60 Years

BACKGROUND

Hemiarthroplasty is a treatment option for femoral neck fractures in patients aged more than 60 years and postoperative dislocation after a posterior approach is not uncommon. The piriformis tendon is one of the structures providing posterior hip stability. However, evidence of piriformis-sparing approach in hemiarthroplasty is unclear regarding a reduced dislocation rate.

METHODS

Between January 2017 and December 2019, 321 patients underwent a posterior approach in consecutive cohorts for a hemiarthroplasty for femoral neck fractures with the minimum 24 months follow-up time (24-60 months). There were two cohorts: (1) 129 underwent the conventional posterior (CP) approach and (2) 192 underwent the piriformis-sparing (PS) approach. The differences in dislocation rate, postoperative Harris Hip Society at 1 and 2 years and other surgical complications were compared in both groups.

RESULTS

There were 6 dislocations of 129 (4.7%) underwent the CP approach and 0 dislocation from 192 underwent the PS approach that had posterior hip dislocations (P = .004). In addition, the CP group had a significantly higher mortality rate (14.7% versus 7.3%, P = .031) and lower functional outcomes as assessed by mean Harris Hip Scores at 1 year (73 versus 78, P = .005) and 2 years postoperatively (73 versus 80, P < .001) relative to the PS group.

CONCLUSION

PS hemiarthroplasty was associated with a lower dislocation and mortality rate. Moreover, this approach gained a superior early to the mid-term functional outcome than the conventional posterior approach in elderly femoral neck fractures.

LEVEL OF EVIDENCE

II, prospective cohort study.

Inter-departmental variation in surgical treatment of proximal femoral fractures: A nationwide observational cohort study

BACKGROUND AND PURPOSE

Hip fractures should be treated based on the best available evidence and cost-effectively to optimize the outcome for this large group of frail patients. This study examined nationwide variation in surgical methods used for hip fractures.

METHODS

In this cohort study 46,243 patients ≥65 years with a trochanteric hip fracture (THF) or a femoral neck fracture (FNF) registered in the Swedish Fracture Register (SFR) between 1 January 2016 and 31 December 2020 were included. Fractures were classified according to the AO Foundation/Orthopaedic Trauma Association (AO/OTA) fracture classification system. The choice of surgical methods was assessed for each fracture type to compare national variation.

RESULTS

21,312 THFs and 24,072 FNFs (67% women) with a mean age of 83 years (SD 8) were surgically treated. In the treatment of two-fragment THFs (AO/OTA A1) departments ranged from using 90% short intramedullary nails to 98% sliding hip screws. Treating displaced FNFs (AO/OTA B3), the proportion of hemiarthroplasty ranged from 9 to 90%, and internal fixation between 0.6 to 21%, depending on the department.

INTERPRETATION

A mature national fracture register permits the monitoring of treatment provided and thus serves as an important aid in assessing compliance with guidelines. The large inter-departmental variation in the surgical management of hip fractures in Sweden appears unwarranted based on the current evidence, indicating a need for updated national guidelines. Further research will have to clarify the impact of this variation on mortality and re-operation rates.

Hip arthroplasty dislocation risk calculator: evaluation of one million primary implants and twenty-five thousand dislocations with deep learning artificial intelligence in a systematic review of reviews

PURPOSE

This paper aims to provide an overview of the possibility regarding the artificial intelligence application in orthopaedics to predict dislocation with a calculator according to the type of implant (hemiarthroplasty, standard total hip arthroplasty, dual mobility, constrained cups) after primary arthroplasty.

MATERIAL AND METHODS

Among 75 results for primary arthroplasties, 26 articles were reviews on dislocation after hemiarthroplasty, 40 after standard total hip arthroplasty, seven about primary dual-mobility arthroplasty (DM THA), and two reviews about constrained implants. Although our search method for systematic reviews covers ten years (2012-2022), none for dual mobility was published before 2016, showing a recent explosion of original articles on this subject. A total of 1,069,565 implants and 26,488 dislocations in primary arthroplasties are included in these 75 reviews. We used a supervised learning model in which models assign objects to groups as input and artificial neural network (ANN) with nodes, hidden layers, and output layers. We considered only four implant types as the input layer. We considered the patient's factors (indication for THA, demographics, spine surgery, and neurologic disease) as the second input values (hidden layer). We considered the implant position as the third input (hidden layer) property including head size, combined anteversion, or spinopelvic alignment. Surgery-related factors, approach, capsule repair, etc. were the fourth input values (hidden layer). The output was a post-operative dislocation or not within three months.

RESULTS

The accuracy for predicting dislocation with this systematic review was 95%. Dislocation risk, based on the type of implant, was wide-ranging, from 0 to 3.9% (mean 0.31%) for the 3045 DM THA, from 0.2 to 1.2% (overall 0.91%) for the 457 constrained liners, from 1.76 to 4.2% (mean 2.1%) for 895,734 conventional total hip arthroplasties, and from 0.76 to 12.2% (mean 4.5%) for 170,329 hemiarthroplasties. In the conventional THA group, many factors increase the risk of dislocation according to the calculator, and only a few (big head, anterior approach) decrease the risk, but not very significantly. In the hemiarthroplasty group, many factors can increase the risk of dislocation until 30%, but none could decrease the risk. According to the calculator, the DM THA and the constrained liner markedly decreased the risk and were not affected by implant position, spine surgery, and spinopelvic position.

CONCLUSION

To our knowledge, this study is the first to yield an implant-specific dislocation risk calculator that incorporates the patient's comorbidities, the position of components, and surgery factors affecting instability risk.

Dislocation rate, revisions and other complications of primary cemented hemiarthroplasty for displaced femoral neck fractures: a single-center cohort study of 743 unselected hips with a mean 2.7-year follow-up

INTRODUCTION

Evidence of whether to use hemiarthroplasty (HA) or total hip arthroplasty for displaced femoral neck fractures (FNF) is still widely debated, especially when taking ambulatory status, age, and patient cognitive status into account. The current study aims to report the rates of dislocations, revisions and other complications for primary cemented HA in patients with displaced FNF.

MATERIALS AND METHODS

Single-center retrospective follow-up study of an unselected historic cohort. 743 consecutive hips (551 W and 192 M) at mean (SD) age of 83.6 (8.4) years received primary cemented HA for displaced FNF by posterolateral surgical approach between January 2012 and December 2019. Patient files and radiographs were evaluated for dislocations, revisions, and other complications until death or end of the follow-up period, and the educational level of the surgeon was noted.

RESULTS

During a mean (SD) follow-up period of 2.7 (2.2) years, there were 6.1% (n = 45) dislocations, in which 82% (first dislocation) appeared within the first 30 postoperative days, and 51% (n = 23) of the dislocations requiring subsequent surgery. At the time of the last available follow-up, 57% (n = 421) of the patients were dead. A non-dislocation related revision was needed in 3.4% (n = 25) of the patients [in which infection accounted for 40% (n = 10) and traumatic periprosthetic fracture for 32% (n = 8)]. Thirty-day mortality was 9.2% and 1-year mortality 25.8%. There were no differences in patient's age, gender, or educational level of the surgeon between the dislocation and the no dislocation groups. Patients aged < 70 years presented with a higher dislocation rate (p < 0.001) than the patients aged > 70 years.

CONCLUSION

Primary HA presents a safe and robust approach with acceptable complication rates in a genuine unselected cohort of displaced FNF, particularly for patients aged > 70.

Do Dual-mobility Cups Reduce Revision Risk in Femoral Neck Fractures Compared With Conventional THA Designs? An International Meta-analysis of Arthroplasty Registries

BACKGROUND

Dual-mobility cups in THA were designed to reduce prosthesis instability and the subsequent risk of revision surgery in high-risk patients, such as those with hip fractures. However, there are limited data from clinical studies reporting a revision benefit of dual-mobility over conventional THA. Collaboration between anthroplasty registries provides an opportunity to describe international practice variation and compare between-country, all-cause revision rates for dual-mobility and conventional THA.

QUESTIONS/PURPOSES

We summarized observational data from multiple arthroplasty registries for patients receiving either a dual-mobility or conventional THA to ask: (1) Is dual-mobility use associated with a difference in risk of all-cause revision surgery compared with conventional THA? (2) Are there specific patient characteristics associated with dual-mobility use in the hip fracture population? (3) Has the use of dual-mobility constructs changed over time in patients receiving a THA for hip fracture?

METHODS

Six member registries of the International Society of Arthroplasty Registries (from Australia, Denmark, Sweden, the Netherlands, the United Kingdom, and the United States) provided custom aggregate data reports stratified by acetabular cup type (dual-mobility or conventional THA) in primary THA for hip fracture between January 1, 2002, and December 31, 2019; surgical approach; and patient demographic data (sex, mean age, American Society of Anesthesiologists class, and BMI). The cumulative percent revision and mortality were calculated for each registry. To determine a global hazard ratio of all-cause revision for dual-mobility compared with conventional THA designs, we used a pseudoindividual patient data approach to pool Kaplan-Meier prosthesis revision data from each registry and perform a meta-analysis. The pseudoindividual patient data approach is a validated technique for meta-analysis of aggregate time-to-event survival data, such as revision surgery, from multiple sources. Data were available for 15,024 dual-mobility THAs and 97,200 conventional THAs performed for hip fractures during the study period.

RESULTS

After pooling of complete Kaplan-Meier survival data from all six registries, the cumulative percent revision for conventional THA was 4.3% (95% confidence interval [CI] 4.2% to 4.5%) and 4.7% (95% CI 4.3% to 5.3%) for dual-mobility THA at 5 years. We did not demonstrate a lower risk of all-cause revision for patients receiving dual-mobility over conventional THA designs for hip fracture in the meta-analysis once between-registry differences were adjusted for (HR 0.96 [95% CI 0.86 to 1.06]). A lower proportion of dual-mobility procedures were revised for dislocation than conventional THAs (0.9% versus 1.4%) but a higher proportion were revised for infection (1.2% versus 0.8%). In most registries, a greater proportion of dual-mobility THA patients were older, had more comorbidities, and underwent a posterior approach compared with conventional THA (p < 0.001). The proportion of dual-mobility THA used to treat hip fractures increased in each registry over time and constituted 21% (2438 of 11,874) of all THA procedures in 2019.

CONCLUSION

The proportion of dual-mobility THAs in patients with hip fractures increased over time, but there was large variation in use across countries represented here. Dual-mobility cups were not associated with a reduction in the overall risk of revision surgery in patients with hip fractures. A randomized controlled trial powered to detect the incidence of dislocation and subsequent revision surgery is required to clarify the efficacy of dual-mobility cups to treat hip fractures.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Bipolar Hemiarthroplasty Does Not Result in a Higher Risk of Revision Compared with Total Hip Arthroplasty for Displaced Femoral Neck Fractures: An Instrumental Variable Analysis of 36,118 Procedures from the Australian Orthopaedic Association National Joint Replacement Registry

BACKGROUND

Previous randomized studies have suggested that there is no short-term difference between the risk of revision following total hip arthroplasty (THA) and hemiarthroplasty (HA) for hip fracture in elderly patients. The aim of the present study was to compare the long-term revision rates of primary THA and HA for femoral neck fracture in order to determine whether unipolar or bipolar HA increases the all-cause risk of revision in patients 50 to 79 years old.

METHODS

Data for 36,188 patients who underwent primary arthroplasty, including 13,035 unipolar and 8,220 bipolar HAs and 14,863 THAs, from September 1, 1999, to December 31, 2019, were obtained from the Australian Orthopaedic Association National Joint Replacement Registry. Unadjusted analyses were performed, as well as analyses adjusted for age, sex, femoral cement, and procedure year. The primary outcome was time to first revision for any cause. Secondary analyses were performed for the reason for revision (i.e., infection, dislocation, and periprosthetic fracture). Instrumental variable analysis of hospital preference (for either HA or THA) was performed in order to mitigate the effect of any unmeasured confounding. All analyses were restricted to hospitals performing at least 10 procedures in the prior year.

RESULTS

A total of 18,955 procedures were available for the comparison of modular unipolar HA to THA. Both the adjusted analysis performed with use of Cox proportional hazards (hazard ratio [HR], 1.94; 95% confidence interval [CI], 1.64 to 2.31; p < 0.001) and the instrumental variable analysis (HR, 2.82; 95% CI, 1.89 to 4.22; p < 0.001) demonstrated a higher risk of revision following modular unipolar HA compared with THA from 3 months postoperatively. A total of 13,168 procedures were available for the comparison of bipolar HA to THA. The adjusted analysis performed with use of Cox proportional hazards showed a significantly higher risk of revision for bipolar HA (HR, 1.29; 95% CI, 1.08 to 1.54; p = 0.01). The instrumental variable analysis showed a similar effect size that was not significant (HR, 1.27; 95% CI, 0.91 to 1.78; p = 0.16).

CONCLUSIONS

Bipolar HA and THA demonstrated no significant difference in revision risk at long-term follow-up. Unipolar HA demonstrated higher risk of revision from 3 months postoperatively compared to THA. The higher risk of revision for dislocation observed following THA may be offset by the higher risk of revision for acetabular erosion or pain following bipolar HA, resulting in more equivalent revision risk.

LEVEL OF EVIDENCE

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

Hip arthroplasty for acute hip fracture in patients with neurological disorders: A report Of 9,702 cases from the Swedish arthroplasty register

INTRODUCTION

The purpose of this study was to investigate neurological disorder as a risk factor for dislocation following arthroplasty for acute hip fractures. We also analysed medical and surgical adverse events (AE), readmission, reoperation, revision, and mortality as secondary outcomes.

METHODS

A longitudinal cohort study using prospectively collected and aggregated data from the Swedish Hip Arthroplasty Register (SHAR) and the Swedish national patient register. All patients presenting with an acute hip fracture and treated with an arthroplasty in the period from 2005 to 2014 from the SHAR were identified. Patients in receipt of bilateral arthroplasties were excluded. Patients with a relevant pre-existing and diagnosed neurological disorder, as defined by ICD-10 codes, were identified (n = 9,702). All other cases (n = 29,411) were available for logistic regression propensity score matching. Patients were 1:1 matched on age, sex, Charlson comorbidity index, total versus hemiarthroplasty, head size, surgical approach, and year of surgery. Dislocations, adverse events, readmission, reoperation, revision, and mortality were studied using Kaplan-Meier analysis and Cox regression.

RESULTS

The risk of dislocations was higher for patients with neurological disorder (HR=1.19, CI 1.03- 1.39, p<0.05). Neurological disorder was associated with increased risk of encountering an adverse event (p<0.001 at 90-days); these patients were at higher risk of dying (HR=1.51, CI 1.47-1.56, p<0.001) however they were less likely to be readmitted (HR=0.73, CI 0.70- 0.76, p<0.001). No excess risks of reoperation (HR=1.02, CI 0.90-1.17; p = 0.73) or revision (HR=1.00, CI 0.86-1.17; p = 0.99) were identified in the study group.

DISCUSSION

Compared to matched controls, individuals with a preoperatively identified neurological diagnosis had higher rates of mortality, dislocations, and adverse events, but this cohort was not at increased risk of reoperation or revision. This study highlights an area of focus for future research to improve the long-term outcomes in patients with neurological disease undergoing arthroplasty for an acute hip fracture.