Perioperative Periprosthetic Fractures Associated With Primary Total Hip Arthroplasty

Post-Acute Care Trends and Disparities After Joint Replacements in the United States, 1991-2018: A Systematic Review

OBJECTIVE

To review evidence on post-acute care (PAC) use and disparities related to race and ethnicity and rurality in the United States over the past 2 decades among individuals who underwent major joint replacement (MJR).

DESIGN

Systematic review.

SETTING AND PARTICIPANTS

We included studies that examined US PAC trends and racial and ethnic and/or urban vs rural differences among individuals who are aged ≥18 years with hospitalization after MJR.

METHODS

We searched large academic databases (PubMed, CINAHL, Embase, Web of Science, and Scopus) for peer-reviewed, English language articles from January 1, 2000, and January 26, 2022.

RESULTS

Seventeen studies were reviewed. Studies (n = 16) consistently demonstrated that discharges post-MJR to skilled nursing facilities (SNFs) or nursing homes (NHs) decreased over time, whereas evidence on discharges to inpatient rehab facilities (IRFs), home health care (HHC), and home without HHC services were mixed. Most studies (n = 12) found that racial and ethnic minority individuals, especially Black individuals, were more frequently discharged to PAC institutions than white individuals. Demographic factors (ie, age, sex, comorbidities) and marital status were not only independently associated with discharges to institutional PAC, but also among racial and ethnic minority individuals. Only one study found urban-rural differences in PAC use, indicating that urban-dwelling individuals were more often discharged to both SNF/NH and HHC than their rural counterparts.

CONCLUSIONS AND IMPLICATIONS

Despite declines in institutional PAC use post-MJR over time, racial and minority individuals continue to experience higher rates of institutional PAC discharges compared with white individuals. To address these disparities, policymakers should consider measures that target multimorbidity and the lack of social and structural support among socially vulnerable individuals. Policymakers should also consider initiatives that address the economic and structural barriers experienced in rural areas by expanding access to telehealth and through improved care coordination.

Femoral Component Design Is Associated With the Risk of Periprosthetic Femur Fracture After Cementless THA in Patients 65 Years or Older

BACKGROUND

Periprosthetic femur fracture is a known complication after THA. The associated risk of cementless femoral component design for periprosthetic femur fracture in a registry population of patients older than 65 years has yet to be clearly identified.

QUESTIONS/PURPOSES

(1) Is femoral stem geometry associated with the risk of periprosthetic femur fracture after cementless THA? (2) Is the presence or absence of a collar on cementless femoral implant designs associated with the risk of periprosthetic femur fracture after THA?

METHODS

We analyzed American Joint Replacement Registry data from 2012 to March 2020. Unique to this registry is the high use of cementless femoral stems in patients 65 years and older. We identified 266,040 primary cementless THAs during the study period in patients with a diagnosis of osteoarthritis and surgeries linked to supplemental Centers for Medicare and Medicaid data where available. Patient demographics, procedure dates, and reoperation for periprosthetic femur fracture with revision or open reduction and internal fixation were recorded. The main analysis was performed comparing the Kheir and Chen classification: 42% (112,231 of 266,040) were single-wedge, 22% (57,758 of 266,040) were double-wedge, and 24% (62,983 of 266,040) were gradual taper/metadiaphyseal-filling cementless femoral components, which yielded a total of 232,972 primary cementless THAs. An additional analysis compared cementless stems with collars (20% [47,376 of 232,972]) with those with collarless designs (80% [185,596 of 232,972]). A Cox proportional hazard regression analysis with the competing risk of death was used to evaluate the association of design and fracture risk while adjusting for potential confounders.

RESULTS

After controlling for the potentially confounding variables of age, sex, geographic region, osteoporosis or osteopenia diagnosis, hospital volume, and the competing risk of death, we found that compared with gradual taper/metadiaphyseal-filling stems, single-wedge designs were associated with a greater risk of periprosthetic femur fracture (HR 2.9 [95% confidence interval (CI) 2.2 to 3.9]; p < 0. 001). Compared with gradual taper/metadiaphyseal-filling stems, double-wedge designs showed an increased risk of periprosthetic femur fracture (HR 3.0 [95% CI 2.2 to 4.0]; p < 0. 001). Collarless stems showed an increased risk of periprosthetic fracture compared with collared stems (HR 7.8 [95% CI 4.1 to 15]; p < 0. 001).

CONCLUSION

If cementless femoral fixation is used for THA in patients 65 years or older, surgeons should consider using gradual taper/metadiaphyseal-filling and collared stem designs because they are associated with a lower risk of periprosthetic femur fracture. Future investigations should compare gradual taper/metadiaphyseal-filling and collared cementless designs with cemented fixation in this population.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Rural-Urban Differences in Hospital and Patient-Reported Outcomes Following Total Hip Arthroplasty

Background

Rural patients have unique health-care factors influencing outcomes of arthroplasty, hypothetically putting these patients at increased risk for complications following total joint arthroplasty. The aim of this study is to better understand differences in patient outcomes and satisfaction between rural and urban patients receiving care in an urban setting and to provide more equitable care.

Methods

A retrospective chart review was performed on patients undergoing primary total hip arthroplasty at a single large academic center between January 2013 and August 2020. Demographic, operative, and hospital outcomes were obtained from the institutional electronic medical record. Rurality was determined by rural-urban code (RUC) classifications by zip code with RUC codes 1-3 defined as urban and RUC 4-10 defined as rural.

Results

Patients from urban areas were more likely to visit the emergency department within 30 days postoperatively (P = .006) and be readmitted within 90 days (P < .001). However, unplanned (P < .001) admissions were higher in the rural group. There was no statistical difference in postoperative complications (P = .4). At 6 months, rural patients had higher patient-reported outcome measures (PROMs) including Hip Disability and Osteoarthritis Outcome Score total (P = .05), Hip Disability and Osteoarthritis Outcome Score interval (P = .05), self-reported functional improvement (P < .05), improvements in pain (P < .05), and that the surgery met expectations (P < .05). However, these values did not reach minimal clinically important difference.

Conclusions

There may be differences in emergency department visits, readmissions, and PROMs in rural vs urban populations undergoing total hip arthroplasty in an urban setting. Patient access to care and attitudes of rural patients toward health care may underlie these findings. Understanding differences in PROMs, satisfaction, and hospital-based outcomes based on rurality is essential to provide equitable arthroplasty care.

Addressing osteoporosis treatment after hemiarthroplasty for a femoral neck fracture: impact on survival rates after a subsequent periprosthetic femoral fracture - a multicenter (TRON group) retrospective study

This study investigated the impact of osteoporosis treatment on the prognosis of patients with periprosthetic femoral fracture (PPF) following femoral neck fracture (FNF). Our results suggested an association between osteoporosis treatment and potentially improved survival prognosis in patients who underwent surgery for PPF. These results imply that osteoporosis treatment may have a beneficial effect on patient outcomes.

PURPOSE

This study aimed to investigate the effect of osteoporosis treatment on the prognosis of periprosthetic femoral fracture (PPF) patients after femoral neck fracture.

METHODS

A multicenter retrospective study named as TRON was conducted. The study population included 156 PPF patients who had undergone hemiarthroplasty for femoral neck fracture between January 2010 and December 2019. Patients were divided based on whether they had received osteoporosis treatment before PPF injury. A log-rank test was used to compare survival rates. We conducted a Cox proportional hazards analysis to identify factors associated with the survival rate after PFF injury.

RESULTS

Twenty-seven of the 156 patients had received osteoporosis treatment prior to PPF injury. The 1-year and 2-year overall survival rates after PPF were 80.9% and 75.3%, respectively. The log-rank test revealed that the 1-year survival rate with and without osteoporosis treatment was 89.5% and 78.1%, respectively (P=0.012). In the Cox proportional hazards analysis, age, BMI, presence or absence of surgery, and presence or absence of osteoporosis treatment showed independent associations with the survival rate after PFF injury. The hazard ratio for the presence of osteoporosis treatment was 0.22 (95% confidence interval 0.07-0.75, P=0.015).

CONCLUSION

The findings of this study suggest an association between osteoporosis treatment and potentially improved survival prognosis in patients who underwent surgery for PPF. These results imply that osteoporosis treatment may have a beneficial effect on patient outcomes. It is important to consider that osteoporosis treatment could be significant not only in preventing secondary fractures but also in potentially improving prognosis in the rare event of PPF.

Incidence and risk factors of in-hospital prosthesis-related complications following total shoulder arthroplasty

BACKGROUND

The occurrence of prosthesis-related complications after total shoulder arthroplasty is devastating and costly. The purpose was to determine the incidence and risk of in-hospital prosthesis-related complications after total shoulder arthroplasty utilizing a large-scale sample database.

METHODS

A retrospective database analysis was performed based on Nationwide Inpatient Sample from 2010 to 2014. Patients who underwent total shoulder arthroplasty were included. Patient demographics, hospital characteristics, length of stay, economic indicators, in-hospital mortality, comorbidities, and peri-operative complications were evaluated.

RESULTS

A total of 34,198 cases were capture from the Nationwide Inpatient Sample database. There were 343 cases of in-hospital prosthesis-related complications after total shoulder arthroplasty and the overall incidence was 1%, with a more than 2.5-fold decrease from 2010 to 2014. Dislocation was the most common category among prosthesis-related complications (0.1%). The occurrence of in-hospital prosthesis-related complications was associated with significantly more total charges and slightly longer length of stay while less usage of Medicare. Risk factors of prosthesis-related complications were identified including younger age (<64 years), female, the native American, hospital in the South, alcohol abuse, depression, uncomplicated diabetes, diabetes with chronic complications, fluid and electrolyte disorders, metastatic cancer, neurological disorders, and renal failure. Interestingly, advanced age (≥65 years) and proprietary hospital were found as protective factors. Furthermore, prosthesis-related complications were associated with aseptic necrosis, rheumatoid arthritis, rotator cuff tear arthropathy, Parkinson's disease, prior shoulder arthroscopy, and blood transfusion.

CONCLUSIONS

It is of benefit to study risk factors of prosthesis-related complications following total shoulder arthroplasty to ensure the appropriate management and optimize consequences although a relatively low incidence was identified.

The Influence of Dorr Type and Femoral Fixation on Outcomes Following Total Hip Arthroplasty for Acute Femoral Neck Fractures: A Multicenter Study

BACKGROUND

The American Academy of Orthopaedic Surgeons guidelines report moderate evidence for cementing femoral stems for hip fractures, mainly derived from hemiarthroplasty literature. This is the first large, nonregistry study examining the influence of femoral fixation, implant type, patient characteristics, and radiographic factors on outcomes after total hip arthroplasty (THA) for acute femoral neck fractures.

METHODS

A multicenter retrospective study was performed of 709 THA cases (199 cemented, 510 cementless) for femoral neck fractures from 2006 to 2020 at three large academic institutions. Demographics, perioperative characteristics, and radiographs were reviewed. Kaplan-Meier survivorship curves were generated for multiple outcomes. Univariate and multivariate analyses were performed with P ≤ .05 denoting significance.

RESULTS

Cementless stems had a higher all-cause aseptic femoral revision rate (5.1 versus 0.5%, P = .002) and periprosthetic femoral fracture rate (4.3 versus 0%, P = .001). Each successive Dorr type had a higher fracture rate with cementless implants: 2.3%, 3.7%, and 15.9% in Dorr A, B, and C, respectively (P < .001). Logistic regression analyses confirmed that cementless stems (P = .02) and Dorr C bone (P = .001) are associated with periprosthetic fractures; collared implants and prophylactic cables did not protect against fractures. There was no difference in rates of dislocation, septic revision, or mortality between groups.

CONCLUSION

Cementless stems during THA for femoral neck fractures have a higher aseptic femoral revision rate, specifically for periprosthetic fractures. Dorr C bone was particularly prone with an alarmingly high fracture rate. All fractures occurred in cementless cases, suggesting that cemented stems may minimize this complication.

LEVEL OF EVIDENCE

III.

Periprosthetic Femoral Fractures in Cementless Short Versus Straight Stem Total Hip Arthroplasty: A Propensity Score Matched Analysis

BACKGROUND

Recent studies indicate a decreased risk of periprosthetic femoral fractures (PFFs) in cementless total hip arthroplasty (THA) for short compared to straight stems. However, the results are still inconclusive. Therefore, we retrospectively investigated the rate of PFFs within the first year between cementless short and straight stem THA.

METHODS

A 1:1 propensity score matching of 3,053 THAs was performed. Two groups including 1,147 short stem THAs implanted through a minimally invasive antero-lateral approach and 1,147 straight stem THAs implanted through a transgluteal Hardinge approach were matched. The rates of PFFs and fracture patterns were compared between both stem types. Risk factors for PFFs were analyzed by multivariate regression analyses.

RESULTS

The overall rate of PFFs was 1.7% in short stem THA and 3.2% in straight stem THA (P = .015). Postoperatively detected Vancouver A fractures occurred significantly more often in straight stem THA (P = .002), while the occurrence Vancouver B fractures did not differ significantly (P = .563). The risk of PFFs was significantly increased for women in straight stem THA (Odds ratio (OR) 2.620; Confidence Interval (CI) 1.172-5.856; P = .019). Increasing age showed a significantly increased odds ratio in short stem (OR 1.103; CI 1.041-1.169, P < .001) and straight stem THA (OR 1.057; CI 1.014-1.101, P = .008).

CONCLUSION

Short stem THA reduces Vancouver Type A PFFs in the trochanteric region compared to straight stem THA, while Vancouver Type B fractures are comparable. Increasing age is a significant risk factor for both stem types, while the risk for PFFs in women was only significantly increased in the straight stem group.

Early, Mid-Term, and Late-Term Aseptic Femoral Revisions After THA: Comparing Causes, Complications, and Resource Utilization

BACKGROUND

Registry data suggest increasing rates of early revisions after total hip arthroplasty (THA). We sought to analyze modes of failure over time after index THA to identify risk factors for early revision.

METHODS

We identified 208 aseptic femoral revision THAs performed between February 2011 and July 2019 using an institutional database. We compared demographics, diagnoses, complications, and resource utilization between aseptic femoral revision THA occurring within 90 days (early), 91 days to 2 years (mid), and greater than 2 years (late) after index arthroplasty.

RESULTS

Early revisions were 33% of revisions at our institution in the time period analyzed. Periprosthetic fractures were 81% of early, 27% of mid, and 21% of late femoral revisions (P < .01). Women were more likely to have early revisions than men (75% vs 53% of mid and 48% of late revisions; P < .01). Patients who had early revisions were older (67.97 ± 10.06) at the time of primary surgery than those who had mid and late revisions (64.41 ± 12.10 and 57.63 ± 12.52, respectively, P < .01). Index implants were uncemented in 99% of early, 96% of mid, and 64% of late revisions (P < .01). Early revisions had longer postoperative length of stay (4.4 ± 3.3) than mid and late revisions (3.0 ± 2.2 and 3.7 ± 2.1, respectively, P = .02). In addition, 58% of early revisions were discharged to an inpatient facility compared with 36% of mid and 41% of late revisions (P = .03).

CONCLUSION

Early aseptic femoral revisions largely occur in older women with uncemented primary implants and primarily due to periprosthetic fractures. Reducing the incidence of periprosthetic fractures is critical to decreasing the large health care utilization of early revisions.

Prospective Short-Term and Return-to-Sports Results of a Novel Uncemented Short-Stem Hip Prosthesis with Metaphyseal Anchorage

Short-stem hip prostheses were developed to treat active patients requiring total hip arthroplasty (THA). This study provides short-term data about a short-stem total hip arthroplasty system. Functional and radiological outcomes as well as return to sports and activity level were assessed. A series of 55 patients was primarily included. Data were available for 47 patients at an average follow-up of 38 ± 4.6 months. The back-to-sports analysis showed a 98% return-to-sports rate (46/47 patients). The average time for return to sports was 13 weeks (± 8) postoperatively. Five patients (10.6%) were more active postoperatively. The Harris Hip Score (HHS) improved from 34.8 (±9.4) preoperatively to 94.7 (±8.4, p ≤ 0.001) and the University of California, Los Angeles (UCLA) score improved from 4.5 (±1.8) to 6.9 (±1.9) (p ≤ 0.001). The High Activity Arthroplasty Score (HAAS) was 12 (±3.6) at 3-year follow-up. Pre- and postoperative UCLA and postoperative HHS and HAAS scores had a positive influence on the return-to-sports rate (p ≤ 0.05). The collection of radiographic data during all postoperative follow-ups showed no signs of radiolucent lines or bone fissures. The complication rate was at 5%. Short-stem systems are equaling conventional prostheses and offer benefits regarding soft tissue and bone stock preservation. Fast recovery and return to sports can be achieved.

Does Femoral Component Cementation Affect Costs or Clinical Outcomes After Hip Arthroplasty in Medicare Patients?

BACKGROUND

Bundled payment initiatives were introduced to reduce costs and improve quality of care. Cemented vs cementless femoral fixation is a modifiable variable that may influence the cost and quality of care. New bundled payment data from the Centers for Medicare and Medicaid Services allowed us to study the influence of femoral fixation strategy on (1) 90-day costs; (2) readmission rates; (3) reoperation rates; (4) length of stay (LOS); and (5) discharge disposition for Medicare patients undergoing total hip arthroplasty.

METHODS

We retrospectively studied 1671 primary total hip arthroplasty Medicare cases, comparing 359 patients who received cemented femoral fixation to 1312 patients who received cementless fixation. Centers for Medicare and Medicaid Services cost data as well as clinical data were reviewed. Demographic differences were present between the 2 cohorts. Statistical analyses were performed, including multiple regression models to adjust for baseline differences.

RESULTS

Controlling for cohort differences, cemented patients were significantly more likely to be discharged home compared to cementless patients. Cemented patients also demonstrated trends toward lower costs, lower readmission rates, and shorter LOS compared to cementless patients. All reoperations within the early postoperative period occurred in patients managed with cementless femoral fixation.

CONCLUSION

Among Medicare patients, cemented femoral fixation outperformed cementless fixation with respect to discharge disposition and also trended toward superiority with regards to LOS, readmission, cost of care, and reoperation. Cemented femoral fixation remains relevant and useful despite the rising popularity of cementless fixation.

Anatomic and Patient Risk Factors for Postoperative Periprosthetic Hip Fractures: A Case-Control Study

BACKGROUND

Periprosthetic fracture remains a major source of reoperation following total hip arthroplasty (THA). Within 90 days of surgery, fractures may occur spontaneously or with minor injury and are therefore more likely related to patient factors including anatomic variation.

METHODS

From 2008 to 2018, 16,254 primary THAs were performed at our institution; of those, 48 were revised for periprosthetic fracture within 90 days of surgery. A control group of 193 patients undergoing THA for hip osteoarthritis (OA) was randomly selected from the source population. We excluded patients with genetic bone disease and THA performed for hip fracture. We used logistic regression to analyze associations between patient factors (demographics, anatomical factors, comorbidities, surgical technique, and implants) and odds of 90-day periprosthetic fracture.

RESULTS

Increased age was significantly associated with fracture (P = .002), as was female gender (P = .046). After adjusting for age and gender, absence of contralateral OA was associated with increased odds of fracture relative to patients with contralateral OA (odds ratio [OR] 3.85, 95% confidence interval [CI] 1.60-9.29), as was having a contralateral THA in place (OR 3.70, 95% CI 1.59-8.60). The neck-shaft angle, femoral offset, and the Dorr classification were not associated with increased odds of fracture. Additionally, the distance from the tip of the trochanter to the top of the femoral head was associated with increased odds of fracture per half centimeter (OR 1.48, 95% CI 1.14-1.93).

CONCLUSION

Risk of early postoperative periprosthetic fracture following THA is increased with age, female gender, and increasing distance from the greater trochanter to the top of the femoral head; and decreased in the setting of contralateral hip OA. The trochanter-head distance correlation with periprosthetic hip fracture indicates that the preoperative anatomy may influence PPF, particularly regarding how that anatomy is reconstructed.

Predictors of Perioperative Vancouver B Periprosthetic Femoral Fractures Associated With the Direct Anterior Approach to Total Hip Arthroplasty

BACKGROUND

There is an association between intraoperative and postoperative femoral fractures and the direct anterior approach (DAA) to total hip arthroplasty (THA). The purpose of our study is to identify risk factors for Vancouver B fractures and to establish a predictable timeline for when these occur.

METHODS

We retrospectively identified patients with Vancouver B periprosthetic femoral fractures (n = 49) after 11,509 elective primary cementless THA procedures through the DAA between 2012 and 2018 at a single institution. Fracture patients were matched to nonfracture patients (n = 267) by date of surgery and surgeon. Clinical and radiographic factors were collected for multivariable analysis to identify predictors of fracture.

RESULTS

Periprosthetic Vancouver B femoral fracture incidence was 0.4%. 48 (98%) fractures were postoperative. Fractures occurred at an average of 44 days after surgery (range: 1 to 653 days) with >85% of fractures occurring in the first 6 weeks postoperatively. Significant variables predictive of fracture included >3 degrees valgus and >5 degrees varus coronal stem malalignment, Dorr B and C femoral geometry, lower canal flare index (2.75 vs 3.20), advanced age, increased comorbidities, greater stem canal fill, and right-sided procedures.

CONCLUSION

Despite an overall low rate of Vancouver B perioperative periprosthetic femoral fractures, it is a devastating complication that typically presents within the first 6 weeks after DAA THA surgery. The risk is increased in patients with unfavorable proximal femoral geometry, coronal stem malalignment, advanced age, increased comorbidities, and right-sided procedures.

Risk Factors for Periprosthetic Femur Fracture and Influence of Femoral Fixation Using the Mini-Anterolateral Approach in Primary Total Hip Arthroplasty

BACKGROUND

The mini-anterolateral (AL) approach for total hip arthroplasty (THA) has gained popularity. In contrast to other approaches, risk factors for periprosthetic femur fractures have not been well established for the AL approach.

METHODS

Six hundred eighty-four primary THAs performed using the AL approach were retrospectively reviewed for risk factors associated with perioperative periprosthetic femur fractures within 3 months of surgery. Risk factors evaluated were gender, age, body mass index, laterality, and Dorr ratio of the proximal femur. Cemented stems and collared uncemented stems were compared to uncemented tapered-wedge and meta-diaphyseal stems. A Student's t-test was used for continuous variables, and a chi-squared test was used for categorical variables.

RESULTS

Of 684 primary THAs performed, 57 (8.3%) resulted in fracture. Twenty-eight (4.1%) occurred intraoperatively and 29 (4.2%) occurred postoperatively within 90 days. All intraoperative fractures were fixed at the time of surgery and healed uneventfully. Of the postoperative fractures, 15 (2.2%) were amenable to nonoperative management and healed. Fourteen (2.0%) required revision arthroplasty. There was a significantly lower rate of fracture in patients receiving cemented or collared stems (0%, n = 101) than in those receiving tapered-wedge or meta-diaphyseal fitting stems (9.8%, n = 583; P = .0009). Odds of fracture increased with female gender (P = .0063) and increasing Dorr ratio (P = .0003). Analysis showed a trend toward increased risk with older age, but did not achieve statistical significance. Body mass index and laterality showed no statistically significant effect.

CONCLUSION

Performing primary THA via the AL approach, 2.0% of patients had a postoperative fracture requiring revision within the first 3 months. With cemented and collared stems, the fracture rate was significantly lower. Surgeons should consider using cemented or collared stems in high-risk patients.

An Ultra-Short Femoral Neck-Preserving Hip Prosthesis: A 2-Year Follow-up Study with Radiostereometric Analysis and Dual X-Ray Absorptiometry in a Stepwise Introduction

BACKGROUND

Total hip arthroplasty (THA) with a diaphyseal stem may risk bone loss. In order to save proximal bone stock in young patients with a high activity level and a long life expectancy, the interest in short stems has evolved. The purpose of this prospective observational cohort study was to evaluate the fixation of, and bone remodeling around, the Primoris femoral neck-preserving hip implant.

METHODS

Fifty younger patients with end-stage osteoarthritis were managed with the Primoris hip implant. We evaluated bone mineral density (BMD) using dual x-ray absorptiometry (DXA) and implant migration using radiostereometric analysis (RSA). A region-of-interest (ROI) protocol for 4 ROIs was applied to assess BMD. The association between BMD and migration was evaluated to determine the fixation of the Primoris implant and bone remodeling in the proximal part of the femur. Follow-up evaluation was performed at regular intervals from day 1 (baseline) until 24 months after surgery.

RESULTS

The major stem migrations were subsidence (Y axis; mean, 0.38 mm) at 6 weeks and varus tilt (rotation) (Z axis; mean, 0.93°) at 6 to 12 months. In ROI4 (the calcar area), a significant gain in bone was found with a mean difference of 4.1% (95% confidence interval [CI], 0.8% to 7.4%; p < 0.02) at 24 months postoperatively. Significant bone loss was found in ROI1 and ROI2, with a mean difference of -4.9% (95% CI, -7.4% to -2.4%; p = 0.0003) and -8.9% (95% CI, -11.5% to -6.2%; p = 0.0001), respectively. Linear regression and multivariate regression analysis showed a significant negative association between maximal total point motion and BMD (p = 0.02, R = 15%; and p < 0.05, R = 26%, respectively).

CONCLUSIONS

The Primoris component showed satisfactory primary stability with promising results at the 24-month follow-up. DXA scans showed limited stress-shielding with the proximal loading pattern of the Primoris. Better bone quality was associated with less implant migration.

LEVEL OF EVIDENCE

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

Risk factors for periprosthetic femoral fractures around total hip arthroplasty: a systematic review and meta-analysis

BACKGROUND

Periprosthetic fractures are becoming increasingly common, often leading to poor patient outcomes. The aim of this study was to identify risk factors associated with periprosthetic femoral fractures (PPFFx).

METHODS

Two independent reviewers conducted a systematic review of the databases MEDLINE, Embase and Cochrane Library according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, from the earliest available date to December 2017. We included all clinical articles reporting more than 100 post-operative PPFFx around total hip arthroplasty (THA). Outcomes included demographics, fracture type, risk factors and time to fracture.

RESULTS

A total of 12 868 PPFFx were reported across 18 eligible studies; 64% occurred following primary THA and 36% occurred after revision THA, and 66% of all fractures were in females. Vancouver B2 fractures were the most common type (39%). We found the odds of sustaining a PPFFx is significantly lower after a primary THA compared to revision THA (odds ratio 0.31, 95% confidence interval 0.24-0.40, P < 0.00001). The incidence of PPFFx is 2.96 per 1000 person-years following primary THA compared to 9.08 per 1000 person-years following revision THA (odds ratio 0.33, 95% confidence interval 0.27-0.40). The time to fracture was 6.03 years following primary THA and 4.08 years following revision THA. Gender and cementation did not significantly affect the odds of fracture.

CONCLUSION

The odds of sustaining a PPFFx following revision THA is three times greater compared to primary THA. Other risk factors including gender and cementation did not affect the odds of fracture.

Evaluating risk factors following surgery for periprosthetic fractures around hip and knee arthroplasties

BACKGROUND

The increasing demand for arthroplasty has resulted in an inevitable rise in the number of periprosthetic fractures around implants. Survival factors looking into patient's comorbidities and how they influence outcome are rare. This study aims to identify correlations between survival post-injury and pre-existing comorbidities.

METHODS

A total of 144 patients underwent operative treatment for either a hip or a knee periprosthetic fracture from January 2008 to August 2017 at our Major Trauma Hospital. The mean age at injury was 80.9 years old (SD 9.9). Each patient had a case-based analysis to ascertain injury characteristics, operative parameters and comorbidities.

RESULTS

The mean survival was 12.7 months (95% CI 8.4-17.1). Survival analysis showed a correlation between age more than 75 years old (p = 0.001), ASA grade of 3 or higher (p = 0.009 Breslow's test), history of CVA or TIA (p = 0.038 Breslow's test), dementia (p = 0.002 log rank test), depression (p = 0.013 log rank test) and gender (p = 0.041, Breslow's test) and survival post-periprosthetic fracture. Survival within the first year following injury was found to be affected by the presence of osteoporosis (p = 0.020) and dementia (p = 0.002).

CONCLUSION

Periprosthetic fractures are associated with a high mortality risk (34.7%). Operative risks can be minimised with careful optimisation and surgical planning. ASA, age and comorbidities (dementia, CVA or TIA, osteoporosis) have a significant correlation with survival post-injury. Hence, careful patient selection for operative treatment is advised.

Early perioperative complication rates and subsidence with the Tribute® short cementless, tapered stem in primary total hip arthroplasty

This study examined early perioperative complications and subsidence following total hip arthroplasty (THA) with a short femoral stem. A retrospective review of 207 consecutive patients (247 hips) having undergone THA via the direct anterior approach produced only six perioperative complications: two intraoperative fractures, three perioperative femur fractures and one dislocation. Subsidence greater than 5 mm was observed in four hips but subsidence did not progress greater than 3 mm at the latest follow-up. Based on these results, cementless THA though the direct anterior approach with a short femoral stem provides a clinical and radiographic advantage while maintaining low complication rates.

Bone remodelling of the proximal femur after total hip arthroplasty with 2 different hip implant designs: 15 years follow-up of the thrust plate prosthesis and the Bi-Metric stem

INTRODUCTION

The thrust plate prosthesis (TPP) was introduced to preserve bone in patients undergoing total hip arthroplasty. We assessed the long-term results of hip arthroplasty in patients who received the TPP compared to a traditional intramedullary stem (Bi-Metric).

METHODS

In this prospective observational cohort study, we evaluated bone mineral density (BMD) using dual-energy X-ray absorptiometry (DXA), radiological imaging and clinical outcome using Harris Hip Score (HHS). Twenty patients received the TPP (group A) and 18 patients received the Bi-Metric stem (group B). Baseline was the 1st postoperative day, and subsequent follow-up was performed at 6 months, 1, 2, 8, 12 and 15 years after surgery. A four regions of interest (ROI) protocol was developed to assess BMD.

RESULTS

In ROI1, bone resorption was significantly higher for group A at 6 months with a mean difference of 10% (95% confidence interval [CI], 4-16; p = 0.003) and 8% (95% CI, 1-15; p = 0.03) at 8 years. Regarding ROI4, group A had a lesser decrease in general compared to group B. The radiological findings did not reveal any subsidence or detectable implant migration. HHS improved from 53 (23-69) to 93 (55-100) in group A and from 51 (24-72) to 94 (78-100) in group B.

CONCLUSION

The TPP was not found to be inferior to the Bi-Metric stem regarding bone preservation. The decrease in BMD in ROI4 was greater in group B. Clinical and radiological results also revealed that the TPP was not inferior to the Bi-Metric stem.

Perioperative Fractures in Cementless Total Hip Arthroplasty Using the Direct Anterior Minimally Invasive Approach: Reduced Risk With Short Stems

BACKGROUND

The direct minimally invasive anterior approach (DMIAA) and the use of uncemented stems demonstrated an increase in intraoperative fractures in recent literature. Whether the different design of the stems additionally influences the incidence of perioperative local complications, was the goal of this study.

METHODS

From January 2008 until June 2010, all patients undergoing primary cementless total hip arthroplasty, using a DMIAA, were consecutively included. The choice of the implant was defined by the day of operation. Age, gender, body mass index, type of prosthesis, and the practical experience of the performing surgeon were retrospectively analyzed. Of main interest were intraoperative fractures, postoperative hematoma, and wound healing.

RESULTS

Six hundred forty consecutive patients (64 years [18-94], 339 female, 53%, body mass index 26) have been included. A Quadra-H stem (Medacta) was used in 457 patients (71%). In 183 (29%) patients, a short stem designed for the DMIAA (130 Fitmore, Zimmer and 53 AMIStem, Medacta) was used. We counted 34 (5.3%) intraoperative fractures (16 at the greater trochanter, 18 proximal shaft fractures), 20 (4%) hematomas, and 8 (2%) wound healing problems. The standard length stem showed more local complications (11.8% vs 4.4%) (P = .014, odds ratio 1.63, confidence interval 1.1-2.4) and significantly more (6.8% vs 1.6%) intraoperative fractures (P = .027, odds ratio 1.98, confidence interval 1.1-3.6).

CONCLUSION

The standard length stem showed more perioperative complications, especially periprosthetic fractures. It seems that these implants not only put more stress to proximal osseous structures, but there might also be more traction and irritation to the soft tissue while preparing, resulting in more hematomas and wound healing problems.