Patient-related predictors of implant failure after primary total hip replacement in the initial, short- and long-terms. A nationwide Danish follow-up study including 36,984 patients

Representativeness of participants in the Danish National Health Survey across 422,371 orthopedic surgeries: a study of hip and knee arthroplasty and hip fracture patients

AIMS

Orthopedic registries have provided valuable knowledge about risk for and prognosis after total hip arthroplasties (THA), knee arthroplasties (KA), and hip fractures. However, registries are often limited by the lack of data on health risk behaviors, quality of life, and social background, which are readily available in surveys. We examined if participants in The Danish National Health Survey, based on self-administered questionnaires, are representative of THA, KA, and hip fracture patients.

METHODS

Patients were identified in the Danish orthopedic registries and linked with survey data (from 2010, 2013, and 2017) on an individual level. Data on age, sex, comorbidity, medication, markers of socioeconomic position, and healthcare utilization were assessed from the Danish medical databases. We calculated the proportions of variables before and after surgery, comparing patients who had and had not participated in surveys.

RESULTS

We included 177,617 THA surgeries (4.5% of patients completed pre-surgery surveys and 7.0% completed post-surgery surveys), 152,154 KA surgeries (7.0% of patients completed pre-surgery surveys and 6.2% completed post-surgery surveys) and 92,600 hip fracture surgeries (3.8% of patients completed pre-surgery surveys and 2.2% completed post-surgery surveys). Survey participants and non-participants had similar age and sex distribution in the three cohorts. Based on comorbidity, medication, and healthcare utilization, participants appeared slightly healthier than non-participants. There was a slight variation in socioeconomic markers for THA and KA patients between participants and non-participants.

CONCLUSION

The Danish National Health Survey provides a sample that appears to be largely representative of all THA, KA, and hip fracture patients in Denmark. Survey data could be a valuable data source for further studies of the risks and outcomes associated with patients undergoing THA and KA and those suffering from hip fractures, while carefully considering the identified similarities and differences when designing studies and analyzing the survey data.

Statins and long-term risk of revision surgery after total hip arthroplasty in osteoarthritis: a multi-source data linkage study

Background

Statins, widely used lipid lowering drugs, have been associated with pleiotropic beneficial effects. Notably, studies conducted in vitro and in vivo suggest a link between statins and bone metabolism. Observational data in humans also hint at a decreased fracture rate among statin users. Revision of total hip arthroplasty (THA) is a serious and costly medical event. Whether statins might influence THA failure is not clear. Aim of the current study is to assess how the preoperative use of statins may influence the risk of THA revision in patients with hip osteoarthritis (OA).

Methods

We performed a retrospective analysis of patients who underwent THA for OA in the Italian RIPO registry of Emilia-Romagna. Electronic health records were scrutinized to gather information regarding comorbidities and statin prescriptions. We employed propensity score (PS) matching to pair 1:1 statin users (SU) with statin non-users (SNU), considering factors such as age, sex, and the duration of follow-up. Survival of THA was compared between the two groups; secondary analyses were performed to ascertain the role of mortality, sex, indication for statin treatment, and statin potency or lipophilicity.

Results

10,927 patients were classified as SU and PS-matched with SNU. SU showed a reduced risk of THA revision over a 15-year period (adjHR 0.76, 95% CI: 0.67-0.88; p < 0.001). Notably, this observation remained consistent regardless of the indication for statin therapy or the specific characteristics of the statin medications prescribed, and it was more pronounced among male patients (adjHR 0.64, 95% CI: 0.52-0.80, p < 0.001).

Conclusion

Our findings suggest that statin treatment is associated with a decreased risk of long-term THA revision in patients with OA, irrespective of the original indication for statin therapy.

Hip Resection Arthroplasty as Definitive Treatment: Indications, Outcomes, and Complications in Paraplegic and Non-Paraplegic Patients

BACKGROUND

Hip resection arthroplasty (HRA) serves as a salvage treatment option for various conditions affecting paraplegic patients. In nonparaplegic individuals, it is often utilized to manage complex infections. There exists a paucity of studies comparing outcomes between paraplegic and nonparaplegic patients undergoing HRA as definitive treatment. This study aimed to analyze the demographics, indications, outcomes, and complications in these two patient groups.

METHODS

A retrospective analysis was conducted on 65 patients who underwent HRA, divided into paraplegic (n = 25) and nonparaplegic (n = 40) groups. Data encompassed demographics, preoperative indications, postoperative complications, and outcomes.

RESULTS

Paraplegic patients exhibited distinct characteristics compared to nonparaplegic counterparts, including younger age (P < 0.001), lower comorbidity scores (P = 0.013), fewer prior hip operations (P = 0.002), and a higher proportion of men (P < 0.001). Septic arthritis emerged as the primary indication for definitive HRA in both groups, constituting 64% of paraplegic and 42.5% of nonparaplegic cases. Nonparaplegic patients experienced a significant reduction in pain scores postoperatively (P < 0.001), with a notable improvement in mobility. Infection eradication rates were comparable between the two groups, with 82 and 92% success rates in paraplegic and nonparaplegic cases, respectively. However, paraplegic patients exhibited a higher reoperation rate (P = 0.041), while nonparaplegic individuals encountered increased major systemic complications (P = 0.052). Although the total complication rate was slightly higher in the nonparaplegic group (75 versus 56%), the difference was not statistically significant (P = 0.211).

CONCLUSIONS

An HRA was the definitive treatment that successfully treated infection in both groups. In the nonparaplegic group, it led to enhanced ambulatory capacity and decreased pain. Paraplegic patients experienced higher rates of reoperation, whereas nonparaplegic patients suffered from greater rates of major systemic complications. These findings provide valuable insights for clinicians considering HRA as a definitive treatment.

Association of osteotomy, age, and component fixation with the outcomes of total hip arthroplasty in patients with hip dysplasia: a Dutch population-based registry study

BACKGROUND AND PURPOSE

 Hip dysplasia can present challenges for total hip arthroplasty (THA) due to anatomic abnormalities. We aimed to assess the association of age, sex, osteotomies prior to THA, and fixation method on 5- and 10-year revision-free implant survival and patient-reported outcome measures (PROMs) of THAs in patients with hip dysplasia.

METHODS

Using Dutch Arthroplasty Register data, we studied hip dysplasia patients receiving primary THAs in 2007-2021 (n = 7,465). THAs were categorized by age, pelvic osteotomy prior to THA (yes/no), and fixation (cemented, uncemented, hybrid, reverse hybrid). Kaplan-Meier and multivariable Cox models were used to determine 5- and 10-year revision-free implant survival and adjusted hazard ratios including 95% confidence intervals (CIs). Reasons for revision and PROMs were compared within the categories.

RESULTS

 We found a 10-year revision-free implant survival of 94.9% (CI 94.3-95.5). Patients younger than 50 years had a 10-year implant survival of 93.3% (CI 91.9-94.7), Patients with prior pelvic osteotomy had a 10-year implant survival of 92.0% (CI 89.8-94.2). Fixation method and sex were not associated with implant survival. Patients with a prior pelvic osteotomy had more revisions due to cup loosening and reported lower PROM scores than patients without earlier osteotomy.

CONCLUSION

 5- and 10-year revision-free implant survival rates of THA for hip dysplasia are 96.4% and 94.9%. Age and prior osteotomies were associated with decreased implant survival rates in patients with hip dysplasia, while fixation method was not. Prior osteotomies were also associated with reduced PROM scores.

Mid-Term Migration Pattern of a Cemented Collared Anatomical Stem-A Retrospective Study Using EBRA-FCA

Background: Aseptic loosening is one of the leading causes of stem revision. Einzel Bild Röntgen Analyse-Femoral Component Analysis allows for the detection of distal stem migration, which is used as a predictive factor for implant longevity. This study aims to demonstrate the migration behavior of a cemented collared anatomical stem. Methods: This study retrospectively examined all patients who received a cemented Lubinus SP II stem (Waldemar Link, Hamburg, Germany) between 2003 and 2019. We used the EBRA-FCA software (University of Innsbruck, Austria) to determine the migration patterns and thoroughly examined the patients' medical histories. In addition, the potential influence of femoral configuration and BMI on the migration behavior was assessed. Results: This study included 61 patients (48 females and 13 males) with a total of 61 stems that met our inclusion criteria. The mean age at surgery was 76 years (ranging from 30 to 93 years). According to EBRA-FCA migration analysis, a median subsidence of 0.7 mm was observed at 24 months and at the final follow-up (median 78 months). Distal stem migration was significantly higher at the 6-month time point in patients with Dorr type A femurs compared to Dorr type B femurs (p = 0.016). Body mass index (BMI) had no significant effect on stem migration. Conclusions: The measured subsidence of the Lubinus SP 2 stem using EBRA-FCA was below established thresholds, indicating excellent long-term outcomes. Although there was significantly increased subsidence in Dorr type A femurs during the initial 6 months, thereafter, no statistically significant difference was observed compared to Dorr type B femurs.

Outcomes of a hydroxyapatite ceramic-coated femoral stem in primary total hip arthroplasty: a report of excellent survivorship from a single United Kingdom centre

BACKGROUND

Hydroxyapatite (HA) coated femoral stems were introduced to enhance the biological fixation at the implant-bone interface, aiming to increase the longevity and survival of the prostheses. We aimed to assess the long-term outcomes of an HA ceramic (HAC) coated stem in primary total hip arthroplasty (THA), assess the stem survival, and clinically evaluate the patients using patient-reported outcome measures (PROMs) and radiological evaluation of stem osseointegration.

PATIENTS AND METHODS

This was a prospective evaluation of a retrospective cohort of 385 patients (442 hips) who underwent primary THA between June 2008 and December 2018. The mean age was 63.83 years (range, 30-82 years). During the follow-up duration, 23 patients died, and 36 patients (38 hips) were lost to follow-up. Prospective data collected for 326 patients (381 hips) was used to evaluate stem survival with the Kaplan-Meier method using aseptic loosening or any revision as the endpoint. Clinical evaluation was done using the EuroQol five-dimension (EQ-5D) scoring system and PROMs using the Oxford Hip Score (OHS) and Merle D'Aubigne Postel (MDP) score. Radiological assessments were performed using the Engh radiological criteria for stem osteointegration.

RESULTS

The mean follow-up duration was 9.39 years (range, 4-14.5 years). The survival of the HAC-coated femoral stem was 100% (95% confidence interval [CI], 96.7-100%) at 14 years with aseptic loosening as the endpoint, and 98.9% (CI, 96.7-100%) at 14 years with stem revision for any reason as the endpoint. The mean OHS was 44.5 (range, 30-48), and the mean MDP score was 15.87 (range, 10-18). Radiological evaluations showed full osseointegration of all stems.

CONCLUSION

This HAC-coated femoral stem has shown excellent survivorship, functional outcomes, and full osseointegration at the final follow-up.

Impact of unplanned second debridement, antibiotics and implant retention on long-term outcomes in knee exchange arthroplasty: Elevated risk of failure and reinfection

Purpose

This study investigates the outcomes of two-stage exchange arthroplasty (EA) for periprosthetic joint infection (PJI) following initial or unplanned repeat debridement antibiotics, and implant retention (DAIR).

Methods

We retrospectively reviewed cases of knee arthroplasty infection treated with two-stage EA after DAIR, spanning from January 1994 to December 2010. A total of 138 patients were included, comprising 112 with initial DAIR and 26 with an unplanned second DAIR. Data on demographics, comorbidities, infection characteristics and causative organisms were analyzed. The primary outcome was implant failure or reinfection, observed over a minimum follow-up of 10 years.

Results

The overall success rate for two-stage EA was 87% (119/138 patients). Factors identified for treatment failure included reinfection with the same pathogen for unplanned second DAIR (hazard ratio [HR] = 3.41; 95% confidence interval [CI] = 1.35-4.38; p = 0.004), higher reinfection rates in patients undergoing EA after an unplanned second DAIR, especially with a prior history of PJI within 2 years (HR = 4.23; 95% CI = 2.39-5.31; p = 0.002), pre-first DAIR C-reactive protein (CRP) levels over 100 mg/dL (HR = 2.52; 95% CI = 1.98-3.42; p = 0.003) and recurrence with the same pathogen (HR = 2.35; 95% CI = 1.32-4.24; p = 0.007). Additional factors such as male gender (HR = 3.92; 95% CI = 1.21-5.25; p = 0.007) and osteoporosis (T score < -2.5; HR = 3.27; 95% CI = 1.23-5.28; p = 0.005) were identified as risk factors for implant failure in all EA cases.

Conclusions

This study identifies key risk factors for worse knee EA outcomes following DAIR, including a pre-first DAIR CRP level over 100 mg/L, same pathogen recurrence, and PJI history within 2 years. It shows implant failure rates remain constant across EA cases, regardless of DAIR sequence, particularly with risk factors like male gender and severe osteoporosis (T score < -2.5). These results underscore the need for careful evaluation before an unplanned second DAIR, given its significant impact on EA success.

Level of Evidence

Level III.

Indications, Clinical Outcomes, and Re-Revisions Following Revision Total Hip Arthroplasty - Does Age Matter?

BACKGROUND

Younger age is associated with increased revision incidence following primary total hip arthroplasty, though the association between age and repeat revision following revision total hip arthroplasty (rTHA) has not been described. This study aimed to describe the incidences and indications for subsequent revision (re-revision) following rTHA based on age.

METHODS

Patients undergoing aseptic rTHA from 2011 to 2021 with minimum 1-year follow-up were retrospectively reviewed. Patients were stratified into 3 groups based on age at the time of index rTHA (ie, <55 years, 55 to 74 years, and >74 years). Perioperative characteristics, complications, and re-revisions were compared between groups.

RESULTS

Of 694 included rTHAs, those in the >74 age group were more likely to undergo rTHA for periprosthetic fracture (P < .001) while those in the <55 age group were more likely to undergo rTHA for metallosis/taper corrosion (P = .028). Readmissions (P = .759) and emergency department visits (P = .498) within 90 days were comparable across ages. Rates of re-revision were comparable at 90 days (P = .495), 1 year (P = .443), and 2 years (P = .204). Kaplan-Meier analysis of all-cause re-revision at latest follow-up showed a nonstatistically significant trend toward increasing re-revisions in the <55 and 55 to 74 age groups. Using logistic regressions, smoking and index rTHA for instability were independently associated with re-revision, while age at index surgery was not.

CONCLUSIONS

While indications for rTHA differ across age groups, rates of 2-year re-revision are statistically comparable between groups. Further studies are warranted to understand the association between age, activity, and re-revision rates after 5 years postoperatively.

No Association Between Previous General Infection and Prosthetic Joint Infection After Total Hip Arthroplasty-A National Register-Based Cohort Study on 58,449 Patients Who Have Osteoarthritis

BACKGROUND

Prosthetic joint infection (PJI) following total hip arthroplasty (THA) is a complication associated with increased risk of death. There is limited knowledge about the association between infection before THA, and risk of revision due to PJI. We investigated the association between any previous hospital-diagnosed or community-treated infection 0 to 6 months before primary THA and the risk of revision.

METHODS

We obtained data on 58,449 patients who were operated with primary unilateral THA between 2010 and 2018 from the Danish Hip Arthroplasty Register. Information on previous infection diagnoses, redeemed antibiotic prescriptions up to 1 year before primary THA, intraoperative biopsies, and cohabitations was retrieved from Danish health registers. All patients had a 1-year follow-up. Primary outcome was revision due to PJI. Secondary outcome was any revision. We calculated the adjusted relative risk with 95% confidence intervals (CI), treating death as competing risk.

RESULTS

Among 1,507 revisions identified, 536 were due to PJI with a cumulative incidence of 1.0% ([CI] 0.9 to 1.2) and 0.9% ([CI] 0.8 to 1.0) for patients who did and did not have previous infection. For any revision, the cumulative incidence was 3.1% ([CI] 2.9 to 3.4) and 2.4% ([CI] 2.3 to 2.6) for patients who did and did not have previous infection. The adjusted relative risk for PJI revision was 1.1 ([CI] 0.9 to 1.4) and for any revision 1.3 ([CI] 1.1 to 1.4) for patients who did have previous infection compared to those who did not.

CONCLUSION

Previous hospital-diagnosed or community-treated infection 0 to 6 months before primary THA does not increase the risk of PJI revision. It may be associated with increased risk of any revision.

Radiographic signs and hip pain 5 years after THA with a cemented stem predict future revision for aseptic loosening: a prospective cohort study

BACKGROUND AND PURPOSE

We aimed to evaluate the long-term predictive value of radiographic abnormality and/or hip pain assessed 5 years following primary total hip arthroplasty (THA) and the occurrence of revision for aseptic loosening between 5 and 25 years postoperatively.

PATIENTS AND METHODS

We included all primary THAs performed between 1996 and 2011 (same uncemented cup, polyethylene-ceramic bearing, 28 mm head, cemented stem) and prospectively enrolled in the institutional registry, for whom baseline and follow-up radiographs were available. At 5 years radiographically we assessed femoral osteolysis and/or stem migration. Pain was evaluated with the Harris Hip pain subscore. Kaplan-Meier survival and Cox regression analyses were performed.

RESULTS

1,317 primary THAs were included. 25 THAs (2%) were revised for aseptic stem loosening. Any abnormal radiographic sign at 5 years was present in 191 THAs (14%). Occasional hip pain was reported by 20% and slight to severe pain by 12% of patients at 5 years. In patients < 60 years, 10 of the 12 later revised for aseptic stem loosening had abnormal radiographs at 5 years vs. 5 of the 13 later revised in those ≥ 60 years. Hazard ratios (HR) were 34 (95% confidence interval [CI] 7-155) in younger vs. 4 (CI 1-11) in the older group. HR for association of hip pain at 5 years with future revision was 3 (CI 1-5).

CONCLUSION

The presence of abnormal radiographic signs 5 years after THA was strongly associated with later revision for aseptic stem loosening, especially in patients < 60 years. The association between pain at 5 years and future revision was much weaker.

Patient-Reported Outcome Measures in Conventional Total Hip Arthroplasty Versus Robotic-Arm Assisted Arthroplasty: A Prospective Cohort Study With Minimum 3 Years' Follow-Up

BACKGROUND

Robotic-arm assisted total hip arthroplasty (RO THA) has been shown to improve the accuracy of component positioning compared with conventional total hip arthroplasty (CO THA). This study reports Patient-Reported Outcome Measures (PROMs) of a previous trial that showed that RO THA was associated with improved accuracy and reduced outliers in acetabular component positioning compared with CO THA.

METHODS

This prospective cohort study included 50 patients undergoing CO THA versus 50 patients receiving RO THA. The Oxford hip score, Forgotten Joint Score (FJS), University of California at Los Angeles hip score were recorded at a minimum of 3 years following surgery.

RESULTS

At minimum 3 years follow-up, there was no statistically significant difference in CO THA versus RO THA with respect to the Oxford hip score [median 42(6.25) versus 41(5.5), P = .914]; FJS [89 (9.25) versus 86 (9), P = .065], and University of California at Los Angeles score [median 7.5 (3) versus 7 (2), P = .381]. None of the study patients had dislocations or underwent revision surgery within 3 years follow-up.

CONCLUSION

The previously reported improvement in accuracy of acetabular component in this study population did not translate to statistically significant improvements in PROMs. Patients in both groups achieved excellent PROMs and there was a trend towards higher FJS scores postoperatively in the RO THA group that did not reach statistical significance. Further studies are needed to assess the significance of these findings on longer-term clinical outcomes and implant survivorships, and also to explore the impact of the enhanced RO THA workflow and functional implant positioning on these outcomes.

A Multi-factor Analysis of Revision in Total Hip Replacement Using the Collarless-Polished-Tapered Stems with Different Cups

OBJECTIVE

Collarless-polished-tapered (CPT) stems have been widely used in total hip replacement (THR). Given that various types of cups are combined with CPT in clinical practice, however, what cup type performs the best for use with CPT is still unclear. This study aimed to investigate the effects of three types of commonly used cups with CPT on revision and survival life using multi-factor analysis.

METHODS

This study is a cohort study using the data between October 1998 to September 2021. The data of THR patients with ZCA All-poly Acetabular Cup, Continuum Acetabular System, and Trilogy Acetabular System with CPT were collected from several hospitals in the UK. The patients aged from 20 to 97 (n = 5981, 2345 male and 3636 female). Age, gender, body mass index, diagnosis, surgeon grade, cup material, cup size, surgical approach, survival life, complications, and Harris hip scores (HHS) were analyzed in relation to revision status. SPSS statistical software was used to analyze the relationship among various factors. The main statistical methods included chi-square with cross tables, analysis of variance (ANOVA) and survival analysis.

RESULTS

The results in relation to HHS shows that the continuum cup has the best outcome in the postoperative period of 1 and 5 years (1 year = 90.7, 5 years = 91.3; P < 0.001); the Trilogy cup was the second (1 year = 88.4, 5 years = 87.3; P < 0.001); and the ZCA cup was the third (1 year = 84.6, 5 years = 82.4; P < 0.001). However, the Trilogy cup performed the best regarding survival life on revision while the Continuum cup was the worst.

CONCLUSION

When the CPT stem is combined with different cups, the trilogy cup shows the best characteristics in terms of survival trends with revision ratios compared with the continuum and ZCA cups, and is therefore recommended by this study.

The impact of Charlson Comorbidity Index on surgical complications and reoperations following simultaneous bilateral total knee arthroplasty

Simultaneous bilateral total knee arthroplasty (TKA) might be associated with higher postoperative morbidity and mortality rates compared with staged bilateral TKA. However, risk factors for surgical complications and reoperations following simultaneous bilateral TKA remain elusive. We conducted this retrospective, single-surgeon case series from 2010 through 2019. A total of 1561 patients who underwent simultaneous bilateral TKA procedures were included. The outcome domains included 30-day and 90-day readmission events for medical or surgical complications and 1-year reoperation events. We performed logistic regression analysis and backward stepwise selection to identify possible risk factors, including age, sex, body mass index, diabetes mellitus (DM), rheumatoid arthritis, American Society of Anesthesiologist (ASA) classification, Charlson Comorbidity Index (CCI), receiving venous thromboembolism (VTE) prophylaxis, or blood transfusion. The overall 30-day, 90-day readmission, and 1-year reoperation rates were 2.11%, 2.88%, and 1.41%, respectively. Higher CCI score (CCI = 4+) was a risk factor for 90-day readmission (aOR: 2.783; 95% CI 0.621-12.465), 90 day readmission for surgical complications (aOR: 10.779; 95% CI 1.444-80.458), and 1 year reoperation (aOR: 4.890; 95% CI 0.846-28.260). Other risk factors included older age, higher ASA level, DM, and receiving VTE prophylaxis. In conclusion, high CCI scores were associated with increased risks of surgical complications and reoperations following simultaneous bilateral TKA procedures.

Hip resurfacing for small-sized osteonecrosis: 73 cases at a median 8years' follow-up

INTRODUCTION

Total hip resurfacing arthroplasty (THRA) is an alternative to conventional total hip replacement (THR) in young patients with osteonecrosis of the femoral head. Series have been small, without criteria regarding extent of necrosis, thus vitiating results. We therefore conducted a retrospective assessment of THRA for small necrosis, to determine (1) implant survival, (2) functional scores, and (3) systemic chromium, cobalt and titanium ion concentrations.

HYPOTHESIS

The study hypothesis was that the revision rate is low, meeting the National Institute for Health and Care Excellence (NICE) criterion of<0.5% revision per year.

MATERIAL AND METHOD

A single-center single-surgeon retrospective study included 62 patients, for 73 RTHAs, with a mean age of 45.6years (range: 23-68years) presenting Ficat stage 3 or 4 osteonecrosis of the femoral head with<330° total Kerboul angle (frontal+lateral angles) on simple preoperative X-ray. Study data comprised implant survival and preoperative and last follow-up functional scores (Postel-Merle-d'Aubigné, Oxford-12, Harris, and Devane) and titanium, chromium and cobalt blood concentrations. Necrosis size was assessed on preoperative Kerboul angle.

RESULTS

At a median 8years' follow-up (IQR: 5.9-9.3years), implant survival was 98.6% (95% CI: 97.22-99.98%). Only 1 implant was exchanged, for femoral loosening. Three other patients underwent revision surgery: 2 cases of lavage for infection, and 1 muscle hernia repair. Postel-Merle-d'Aubigné, Oxford-12 and Harris functional scores and Devane activity scores were significantly improved at follow-up, by a median +5 (IQR: 5 to 7), -26 (IQR: -29 to -23), +55 (IQR: 49 to 61) and +1 (IQR: 1 to 2), respectively (all p<0.001). Ion concentrations at last follow-up for titanium, chromium and cobalt were respectively 4.0μg/L (range: 3.6-4.1), 1.1μg/L (range: 0.8-1.9) and 1.1μg/L (range: 0.6-1.8).

CONCLUSION

THRA is a useful option in the long-term for young patients with osteonecrosis with Kerboul angle<330°.

LEVEL OF EVIDENCE

IV, retrospective study.

Hip Preservation or Total Hip Arthroplasty? A Retrospective Case-Control Study of Factors Influencing Arthroplasty Decision-Making for Patients with Osteonecrosis of the Femoral Head in China

OBJECTIVE

At present, there is no consensus or guidance on indications for osteonecrosis of the femoral head (ONFH) patients to receive hip arthroplasty (THA) treatment. This study aims to explore the factors that influence the decision-making for THA in patients with ONFH, and to provide references for clinical decision for ONFH patients to be indicated for THA or hip preservation.

METHODS

This retrospective case-control study involved data for ONFH patients from July 2016 to October 2021 from the China Osteonecrosis of the Femoral Head Database (CONFHD). The patients with ONFH, and unilateral hip affected at the first visit were divided into THA group and non-THA group according to if they had undergone THA treatment. The differences between the two groups of patients in terms of gender, age at the time of consultation, body mass index (BMI), etiology, onset side, association research circulation osseous (ARCO) stage, hip joint function, visual analog scale (VAS), etc. were analyzed. Multivariate binomial logistic regression analysis was then applied to evaluate the risk factors of ONFH patients who underwent THA during the first visit.

RESULTS

A total of 640 patients were recruited for analysis, including 209 cases from the THA group and 431 cases from the non-THA group. The results of univariate analysis showed that the two groups of patients were significantly different in the following six indicators: age (59 vs. 46, Z = -9.58, p < 0.001), duration of disease (78 vs. 17, Z = -16.14, p < 0.001), gender composition (χ²  = 8.09, p = 0.004), disease etiology (χ²  = 33.04, p < 0.001), ARCO stage (χ²  = 334.86, p < 0.001), flexion of hip joint (χ²  = 172.33, p < 0.001). However, the comparison between the two groups on VAS (Z = -0.82, p = 0.41), BMI (Z = -1.35, p = 0.18), and onset side (χ²  = 1.53, p = 0.22) did not obviously differ. The results regression analysis showed that the age at the time of consultation, duration of disease, ARCO stage, and the hip joint function affected the decision making if the patients should undergo THA. The results of receiver operating characteristic curve (ROC) analysis showed that aforementioned indicators were satisfactory in predicting whether patients with ONFH would be treated with THA. The regression model using the above four indicators as comprehensive indicators has satisfactory performance in predicting whether to perform THA, and the area under the curve (AUC) is 93.94%.

CONCLUSION

These factors such as age, duration of disease, ARCO stage, and hip flexion function should be considered comprehensively before making decisions to perform THA or not in our clinical practice.

Analysis of patient characteristics and outcomes related to distance traveled to a tertiary center for primary reverse shoulder arthroplasty

INTRODUCTION

The reasons for referral and travel patterns are lacking for patients undergoing reverse shoulder arthroplasty (RSA). The purpose of this study was to compare comorbidities, surgical time, cost and complications between local and distant primary RSA patients.

METHODS

Between 2007 and 2015, 1,666 primary RSAs were performed at our institution. Patients were divided into two cohorts, local patients (from within Olmstead county and surrounding counties, 492 RSAs) and those from a distance (1,174 RSAs).

RESULTS

Local patients were older (74 vs 71 years, p < .001), more likely to have RSA for fracture, had a higher Charlson comorbidity score (3.8 vs 3.2, p < .001) and longer hospital stays (2.0 vs 1.8 days, p < 0.001) compared to referred patients. Referral patients required longer operative times (95 vs 88 min, p = .002), had higher hospitalization costs ($19,101 vs $18,735, p < .001), and had a higher rate of prior surgery (32% vs 24%, p < .001). There were no differences between cohorts regarding complications or need for reoperation.

CONCLUSIONS

Patients traveling from a distance to undergo primary RSA had longer operative times and were more likely to have had prior surgery than local patients. This may demonstrate the referral bias seen at large academic centers and should be considered when reviewing RSA outcomes, hospital performance, and calculating insurance reimbursement.

LEVEL OF EVIDENCE

Level IV.

The Utility of Machine Learning Algorithms for the Prediction of Early Revision Surgery After Primary Total Hip Arthroplasty

BACKGROUND

Revision total hip arthroplasty (THA) is associated with increased morbidity, mortality, and healthcare costs due to a technically more demanding surgical procedure when compared with primary THA. Therefore, a better understanding of risk factors for early revision THA is essential to develop strategies for mitigating the risk of patients undergoing early revision. This study aimed to develop and validate novel machine learning (ML) models for the prediction of early revision after primary THA.

METHODS

A total of 7,397 consecutive patients who underwent primary THA were evaluated, including 566 patients (6.6%) with confirmed early revision THA (<2 years from index THA). Electronic patient records were manually reviewed to identify patient demographics, implant characteristics, and surgical variables that may be associated with early revision THA. Six ML algorithms were developed to predict early revision THA, and these models were assessed by discrimination, calibration, and decision curve analysis.

RESULTS

The strongest predictors for early revision after primary THA were Charlson Comorbidity Index, body mass index >35 kg/m2, and depression. The six ML models all achieved excellent performance across discrimination (area under the curve >0.80), calibration, and decision curve analysis.

CONCLUSION

This study developed ML models for the prediction of early revision surgery for patients after primary THA. The study findings show excellent performance on discrimination, calibration, and decision curve analysis for all six candidate models, highlighting the potential of these models to assist in clinical practice patient-specific preoperative quantification of increased risk of early revision THA.

Effects of Comorbidities on Pain and Function After Total Hip Arthroplasty

Background

The growing number of patients undergoing total hip arthroplasty (THA) and postoperative outcomes receive increasing attention from doctors and patients. This study aimed to elucidate the effects of comorbidities on postoperative function, pain, complications, readmission rate, and mortality.

Methods

We included consecutive patients who underwent primary unilateral THA between 2017 and 2019. The Charlson comorbidity index (CCI) and the WOMAC and SF-36 (physical function, body pain) scales were assessed preoperatively and at 3, 6, 12, and 24 months postoperatively. The complications, 30-day readmission, and mortality rates assessed the impact of comorbidities and their changes over time on the WOMAC and SF-36 scores during follow-up. We used mixed model linear regression to examine the association of worsening comorbidity post-THA with change in WOMAC and SF-36 scores in the subsequent follow-up periods, controlling for age, length of follow-up, and repeated observations.

Results

This study included 468 patients, divided into four groups based on comorbidity burden (CCI-0, 1, 2, and ≥3). The physiological function recovery and pain scores in the CCI ≥ 3 group were inferior to the other groups and took longer than the other groups (6 vs. 3 months) to reach their best level. The four groups preoperative waiting times were 2.41 ± 0.74, 2.97 ± 0.65, 3.80 ± 0.53, and 5.01 ± 0.71 days, respectively. The complications, 30-day readmission, and 1-year mortality rates for the overall and the CCI ≥ 3 group were 1.92% and 4.69%, 0.85% and 2.01%, and 0.43% and 1.34%, respectively, with no mortality in the other groups.

Conclusion

Patients with higher CCI were more susceptible to physical function and pain outcome deterioration, experienced longer waiting time before surgery, took longer to recover, and had higher rates of complications, 30-day readmission, and mortality after THA. Older age in the group led to a greater impact.

High Charlson Comorbidity Index Score is associated with early fracture-related complication for internal fixation of neck of femur fractures

The incidence of geriatric hip fractures continues to rise in our aging population and has become a major public health concern globally. The primary outcome of this study was to determine whether Age-adjusted Charlson Comorbidity Index (ACCI) is associated with increased fracture-related complications in neck of femur fractures treated by internal fixation. This was a cohort study between January 2014 to June 2018. All patients ≥ 50 years old with an acute neck of femur fracture after low-energy trauma fixed with cannulated hip screws were included and followed-up for 1 year at a tertiary centre. Primary outcome was to determine whether ACCI was associated with increased fracture-related complications. Secondary outcomes were revision rate, mortality, and function after surgery. Further analysis were performed within a “younger” group (age 50–65) and “elder” group (age > 65), as displaced fractures (Garden Type III/IV) were in “younger” group. 233 hip fractures (68 males; 165 females) with a mean age of 73.04 ± 12.89 were included in the study. Surgical outcomes showed that the complication rate of hip screw fixation for all patients was 21.5% (50 patients) at 1 year. ACCI was significantly higher in all patients with complications (p = 0.000). Analysis within “younger” (p = 0.000) and “elder” groups (p = 0.006) both showed significance. Stepwise logistic regression modelling showed ACCI had positive correlation with complications with ACCI = 6 (OR 4.27, p = 0.02). R² values were comparatively better after controlled by Garden Type III/IV at ACCI = 4 (OR 6.42 (1.70, 24.25), p = 0.01). The authors recommend that for patients with a Garden Type I/II and ACCI ≥ 6 or a Garden Type III/IV and ACCI ≥ 4, a direct arthroplasty surgery should be considered.

The association between socioeconomic status and the 30- and 90-day risk of infection after total hip arthroplasty : a registry-based cohort study of 103,901 patients with osteoarthritis

AIMS

The aim of this study was to examine whether socioeconomic status (SES) is associated with a higher risk of infections following total hip arthroplasty (THA) at 30 and 90 days.

METHODS

We obtained individual-based information on SES markers (cohabitation, education, income, and savings) on 103,901 THA patients from Danish health registries between 1 January 1995 and 31 December 2017. The primary outcome measure was any hospital-treated infection (i.e. all infections). The secondary outcomes were further specified to specific hospital-treated infections (pneumonia, urinary tract infection, and periprosthetic joint infection). The primary timepoint was within 90 days. In addition, the outcomes were further evaluated within 30 days. We calculated the cumulative incidence, and used the pseudo-observation method and generalized linear regression to estimate adjusted risk ratios (RRs) with 95% confidence intervals (CIs) for each marker.

RESULTS

The cumulative incidence of any infection at 90 days was highest in patients who lived alone (1.5% (95% CI 1.3 to 1.6)) versus cohabitant (0.7% (95% CI 0.7 to 0.8)), had the lowest educational achievement (1.1% (95% CI 1.0 to 1.2)) versus highest (0.7% (95% CI 0.5 to 0.8)), had the lowest income (1.6% (95% CI 1.5 to 1.70)) versus highest (0.4% (95% CI 0.3 to 0.5)), or had lowest savings (1.3% (95% CI 1.2 to 1.4)) versus highest (0.7% (95% CI 0.6 to 0.8)). Within 90 days, the RRs for any infection were 1.3 (95% CI 1.2 to 1.4) for patients living alone versus cohabiting, 1.2 (95% CI 1.0 to 1.3) for low education achievement versus high, 1.7 (95% CI 1.4 to 2.1) for low income versus high income, and 1.5 (95% CI 1.4 to 1.8) for low savings versus high savings. The same trends were also seen for any infections within the first 30 days.

CONCLUSION

Our study provides evidence that socioeconomic inequality adversely influences the risk of infection after THA, thus contributing to healthcare disparities and inequalities. We found that living alone, low educational achievement, low income, or low savings were associated with higher risks of infections within the first 30 and 90 days after THA. Therefore, the development of targeted intervention strategies with the aim of increasing awareness of patients identified as being at greatest risk is needed to mitigate the impact of SES on the risk of infections following THA. Cite this article: Bone Joint J 2022;104-B(2):221-226.

The Use of Artificial Neural Networks for the Prediction of Surgical Site Infection Following TKA

This is a retrospective study. Surgical site infection (SSI) is associated with adverse postoperative outcomes following total knee arthroplasty (TKA). However, accurately predicting SSI remains a clinical challenge due to the multitude of patient and surgical factors associated with SSI. This study aimed to develop and validate machine learning models for the prediction of SSI following primary TKA. This is a retrospective study for patients who underwent primary TKA. Chart review was performed to identify patients with superficial or deep SSIs, defined in concordance with the criteria of the Musculoskeletal Infection Society. All patients had a minimum follow-up of 2 years (range: 2.1-4.7 years). Five machine learning algorithms were developed to predict this outcome, and model assessment was performed by discrimination, calibration, and decision curve analysis. A total of 10,021 consecutive primary TKA patients was included in this study. At an average follow-up of 2.8 ± 1.1 years, SSIs were reported in 404 (4.0%) TKA patients, including 223 superficial SSIs and 181 deep SSIs. The neural network model achieved the best performance across discrimination (area under the receiver operating characteristic curve = 0.84), calibration, and decision curve analysis. The strongest predictors of the occurrence of SSI following primary TKA, in order, were Charlson comorbidity index, obesity (BMI >30 kg/m²), and smoking. The neural network model presented in this study represents an accurate method to predict patient-specific superficial and deep SSIs following primary TKA, which may be employed to assist in clinical decision-making to optimize outcomes in at-risk patients.

Subsidence of a metaphyseal-anchored press-fit stem after 4-year follow-up: an EBRA-FCA analysis

PURPOSE

Uncemented stem migration analysis by EBRA-FCA (Einzel-Bild-Roentgen Analyse, Femoral Component Analyse) has been seen to be a good predictive indicator for early implant failure. In this study, we investigated the migration behavior of a cementless metaphyseal-anchored press-fit stem after 4-year follow-up.

METHODS

Applying a retrospective study design, we reviewed all consecutive patients who between 2012 and 2017 received a cementless Accolade II press-fit stem at our Department. We reviewed medical histories and performed radiological measurements using EBRA-FCA software. EBRA-FCA measurements and statistical investigations were performed by two independent investigators.

RESULTS

A total of 102 stems in 91 patients (female 60; male 31) fulfilled our inclusion criteria. Mean age at surgery was 66.2 (range 24.3-92.6) years. EBRA migration analysis showed a mean subsidence of 1.4 mm (range 0.0-12.0) at final follow-up. The angle between stem and femur axis was 0.5° (range 0.0°-2.8°) after 48 months. No correlations between gender or Dorr types and subsidence were found (p > 0.05). A body mass index > 30 kg/m² showed a significant increase in stem subsidence within the first 6 (p = 0.0258) and 12 months (p = 0.0466) postoperative.

CONCLUSIONS

Migration pattern of the metaphyseal-anchored stem and a low subsidence rate at final follow-up may predict a good long-term clinical result.

TRIAL REGISTRATION

Number: 20181024-1875.

Migration characteristics of the Corail hydroxyapatite-coated femoral stem-a retrospective clinical evaluation and migration measurement with EBRA

PURPOSE

Uncemented stem migration analysis by EBRA-FCA (Einzel-Bild-Roentgen Analyse, Femoral Component Analysis) has been seen to be a good predictive indicator for early implant failure. In this study, we investigated the migration behavior of a cementless press-fit stem after two years follow-up. Stem type and postoperative gap between collar and femur were evaluated as a risk factor.

METHODS

Applying a retrospective study design, we reviewed all consecutive patients who between 2013 and 2017 received a cementless press-fit Corail stem (DePuy Orthopaedics Inc., Warsaw, IN, USA) at our Department. We reviewed medical histories and performed radiological measurements using EBRA-FCA software.

RESULTS

A total of 109 stems in 105 patients (female: 60; male: 45) fulfilled our inclusion criteria. Mean age at surgery was 67.8 (range, 21.6-90.5) years. EBRA migration analysis showed a mean subsidence of 1.8 mm (range, 0.0-12.1) at final follow-up. At 18 months mean subsidence of collared stems was significantly lower than in the collarless group [1.3 mm (range, 0.0-7.6) vs. 3.2 mm (range, 0.5-10.7), p = 0.0104]. Collared stems resting on the femoral cut presented a tendency to less subsidence than did collared stems showing a postoperative gap between collar and femur (1.3 vs. 2.0 mm) without finding statistical significance (p > 0.05).

CONCLUSIONS

Low subsidence and the migration pattern of the cementless press-fit stem may predict a good long-term result. Collared stems investigated in our study provide good stability and are able to prevent significant subsidence. Trial registration number and date of registration: Number: 20181024-1875; Date: 2018-10-24.

Bioactive Coatings on Titanium: A Review on Hydroxylation, Self-Assembled Monolayers (SAMs) and Surface Modification Strategies

Titanium (Ti) and its alloys have been demonstrated over the last decades to play an important role as inert materials in the field of orthopedic and dental implants. Nevertheless, with the widespread use of Ti, implant-associated rejection issues have arisen. To overcome these problems, antibacterial properties, fast and adequate osseointegration and long-term stability are essential features. Indeed, surface modification is currently presented as a versatile strategy for developing Ti coatings with all these challenging requirements and achieve a successful performance of the implant. Numerous approaches have been investigated to obtain stable and well-organized Ti coatings that promote the tailoring of surface chemical functionalization regardless of the geometry and shape of the implant. However, among all the approaches available in the literature to functionalize the Ti surface, a promising strategy is the combination of surface pre-activation treatments typically followed by the development of intermediate anchoring layers (self-assembled monolayers, SAMs) that serve as the supporting linkage of a final active layer. Therefore, this paper aims to review the latest approaches in the biomedical area to obtain bioactive coatings onto Ti surfaces with a special focus on (i) the most employed methods for Ti surface hydroxylation, (ii) SAMs-mediated active coatings development, and (iii) the latest advances in active agent immobilization and polymeric coatings for controlled release on Ti surfaces.

Treatment Options for End-Stage Hip Disease in Adolescents: To Replace, Fuse, or Reconstruct?

INTRODUCTION

This paper aims to review the indications criteria for the surgical treatment of adolescents with hip osteoarthritis and summarize the contemporary techniques that orthopaedic surgeons can apply for hip reconstruction.

DISCUSSION

Hip osteoarthritis remains a concerning burden to North American society. While the rate of total hip replacement (THR) in younger patients has increased in the last decades, younger patients may have a higher risk of revision hip replacement because of their increased level of activity and expected patient longevity compared with the elderly. Increased demand for multiple revision surgeries is a concern for the adolescent patient. Although in general THR has been increasingly recommended for the treatment of end-stage osteoarthritis secondary to pediatric hip disorders, hip arthrodesis remains a beneficial alternative for the treatment of severe hip disease secondary to infection and for patients who desire to engage in a very active lifestyle. Hip preservation procedures are ideally performed in the prearthritic stage or in hips with minimal degeneration to preserve the joint and achieve the most optimal outcomes. However, adolescents and young adults with moderate and rarely advanced arthritis may benefit from surgical treatment using hip preservation techniques.

CONCLUSIONS

Treatment of adolescents with pain and dysfunction because of end-stage hip disease is challenging and controversial. THR and arthrodesis are the 2 principal alternatives. However, in particular circumstances, hip reconstruction may be recommended.

The Effect of Modern Antiretroviral Therapy on Complication Rates After Total Hip Arthroplasty

Background:

Antiretroviral therapy (ART) remains the cornerstone of decreasing morbidity and mortality in patients with human immunodeficiency virus (HIV), but additional information on its impact on total hip arthroplasty (THA) complication rates is needed to mitigate risks postoperatively. Therefore, we sought to examine patients with HIV who were and were not taking ART compared with a cohort without HIV in the setting of primary THA with respect to the following outcomes: length of stay, readmissions, and postoperative infection.

Methods:

A retrospective database review was performed with PearlDiver for patients who underwent THA from 2010 to 2019 (n = 729,101). Patients with HIV who were and were not taking ART were then identified and were matched with patients without HIV at a 1:1:1 ratio based on age, sex, Charlson Comorbidity Index, diabetes, obesity, and tobacco use, resulting in 601 patients in each cohort. Length of stay, 30-day readmissions, and complications at 90 days and 1 year were analyzed. Continuous outcomes were measured via Student t tests, and categorical outcomes were measured via chi-square analyses.

Results:

Patients with HIV who were and were not taking ART were found to have similar lengths of stay compared with patients without HIV (range, 4.1 to 4.3 days). Readmission rates were slightly higher in patients with HIV who were taking ART at 4.2% (odds ratio [OR], 1.96 [95% confidence interval (CI), 0.99 to 3.87]) and patients with HIV who were not taking ART at 3.5% (OR, 1.63 [95% CI, 0.81 to 3.30]) compared with patients without HIV at 2.1%. Periprosthetic joint infection rates at 1 year were slightly higher among patients with HIV who were not taking ART at 5.3% (OR, 1.41 [95% CI, 0.82 to 2.45]) compared with patients with HIV who were taking ART at 4.2% (OR, 1.09 [95% CI, 0.61 to 1.94]) and patients without HIV at 3.8%.

Conclusions:

Patients with HIV who are and are not taking ART are approaching normalization to the general population in the setting of THA. It is important to note that, although complications may have been mitigated by modern therapy, extreme care should be taken while clinically evaluating these patients prior to the surgical procedure given the complexity of their clinical status. The findings of this study underscore the utility of ART and patient optimization to reduce risk in this patient population.

Level of Evidence:

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

Silane-Coating Strategy for Titanium Functionalization Does Not Impair Osteogenesis In Vivo

Silane-coating strategy has been used to bind biological compounds to the titanium surface, thereby making implant devices biologically active. However, it has not been determined if the presence of the silane coating itself is biocompatible to osseointegration. The aim of the present study was to evaluate if silane-coating affects bone formation on titanium using a rabbit model. For this, titanium screw implants (3.75 by 6 mm) were hydroxylated in a solution of H₂SO₄/30% H₂O₂ for 4 h before silane-coating with 3-aminopropyltriethoxysilane (APTES). A parallel set of titanium screws underwent only the hydroxylation process to present similar acid-etched topography as a control. The presence of the silane on the surface was checked by x-ray photoelectron spectroscopy (XPS), with scanning electron microscopy (SEM) and atomic force microscopy (AFM). A total of 40 titanium screws were implanted in the tibia of ten New Zealand rabbits in order to evaluate bone-to-implant contact (BIC) after 3 weeks and 6 weeks of healing. Silane-coated surface presented higher nitrogen content in the XPS analysis, while micro- and nano-topography of the surface remained unaffected. No difference between the groups was observed after 3 and 6 weeks of healing (p > 0.05, independent t-test), although an increase in BIC occurred over time. These results indicate that silanization of a titanium surface with APTES did not impair the bone formation, indicating that this can be a reliable tool to anchor osteogenic molecules on the surface of implant devices.

Good mid-term results with the trident peripheral self-locking cup: a clinical evaluation and migration measurement with EBRA

INTRODUCTION

The most common cause of failure in total hip arthroplasty (THA) is aseptic loosening. Uncemented cup migration analysis by means of Einzel-Bild-Roentgen-Analyse (EBRA) has shown to be a good predictive indicator for early implant failure if the cup migrates more than 2 mm within 4 years after surgery. In this study, we performed a migration analysis of an uncemented peripheral self-locking (PSL) press-fit cup after 4 years follow-up.

MATERIALS AND METHODS

We retrospectively reviewed all patients who received a trident PSL press-fit cup at our department between 2004 and 2017. A total of 636 patients were identified. As inclusion criteria for radiological analysis, a minimum follow-up of 2 years was defined. We reviewed medical histories and performed radiological analysis using EBRA software. EBRA measurements and statistical investigations were performed by two independent investigators.

RESULTS

A total of 149 cups in 146 patients (female 82; male 64) met our inclusion criteria. Mean age at surgery was 65 years (33-89). We found a significant improvement in the WOMAC score pre- to postoperative (p < 0.0001). EBRA migration analysis showed a mean total migration of 0.6 mm (0.0-8.2) over our follow-up period of 4 years. Of the investigated cups, 69.8% showed a migration rate smaller than 2 mm in the investigated follow-up.

CONCLUSION

The acetabular cup used in our study provides low migration at final follow-up. Therefore, a good long-term outcome can be expected for the PSL cup.

TRIAL REGISTRATION

Trial registration number is 20181024-1875 and date of registration is 2018-10-24.

Two-year radiologic assessment of the Pinnacle cup-a migration analysis with EBRA

INTRODUCTION

The most common cause of failure in total hip arthroplasty (THA) is aseptic loosening. Uncemented cup migration analysis by EBRA (Einzel-Bild-Roentgen-Analyse) has shown to be a good predictive indicator for early implant failure if the cup migrates more than 1 milimeter (mm) within the first 2 years after surgery. In this study, we investigated the migration behaviour of an uncemented press-fit cup after 2 years follow-up.

MATERIALS AND METHODS

Applying a retrospective study design, we reviewed all consecutive patients who received an uncemented press-fit cup at our Department between 2013 and 2018. A total of 484 patients were identified. We reviewed medical histories and performed radiological measurements using EBRA-Cup software. EBRA measurements and statistical investigations were performed by two independent investigators.

RESULTS

A total of 165 cups in 159 patients (female: 90; male: 69) met our inclusion criteria. Mean age at surgery was 66.7 (range 18.4-90.5) years. EBRA migration analysis showed a mean total migration of 0.7 mm (range 0.0-6.3) over our follow-up period of 2 years. Of the investigated cups, 53.2% showed less than 1 mm migration in the investigated follow-up period.

CONCLUSION

In conclusion, the Pinnacle cup used in our study provides low mean migration at final follow-up. Based on the assumption of secondary stabilization, good long-term outcome of the Pinnacle cup can be expected.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

Number: 20181024-1875; Date: 2018-09-20.

Total hip arthroplasty in patients with slipped capital femoral epiphysis: a systematic analysis of 915 cases

There is limited evidence on the outcomes of Total Hip Arthroplasty (THA) in Slipped Capital Femoral Epiphysis (SCFE) patients. This systematic review aims to evaluate the current literature in terms of survival rate, functional outcomes, complications and types of implants of THA in SCFE patients. Following the established methodology of PRISMA guidelines, PubMed, Cochrane library, ScienceDirect and Ovid MEDLINE were systematically searched from inception to September 2018. The search criteria used were: (“total hip arthroplasty’’ OR ‘’total hip replacement’’ OR “hip arthroplasty’’ OR ‘’hip replacement’’) AND (‘’slipped capital femoral epiphysis’’ OR ‘’slipped upper femoral epiphysis’’ OR ‘’femoral epiphysis’’). Ten studies were finally included in the analysis and were qualitatively appraised using the Newcastle-Ottawa tool. Variables were reported differently between studies. The sample size varied from 12 to 374 THAs. A total of 877 patients undergone 915 THAs. The mean reported follow-up ranged from 4.4 to 15.2 years and the mean patients’ age at the time of THA from 26 to 50 years. Four studies specified the type of implants used, with 62% being uncemented, 24% hybrid (uncemented cup/cemented stem) and 14% cemented. All but three studies reported the mean survival of implants that ranged from 64.9% to 94.8%. A limited number of complications were mentioned. There was a tendency for more favorable functional outcomes in modern studies. Modern THA-studies in SCFE patients showed improvement of survivorship, clinical outcomes and patient satisfaction. Future higher-quality studies are necessary to estimate long-term postoperative outcomes better.

Can a surgeon predict the longevity of a total hip replacement?

INTRODUCTION

The purpose of this study was to examine the ability of a surgeon to predict survival of a total hip replacement (THR) based on the patient's diagnosis, demographics, postoperative activity level and the surgical technique.

METHODS

4 experienced hip surgeons were asked to predict the longevity of 131 Charnley THRs, performed by the senior author (GH) 22-35 years ago, by providing them with pre- and postoperative radiographs, and data concerning patient's diagnosis, demographics, postoperative activity level and the surgical technique. This process was repeated 3 months later.

RESULTS

There was only a slight agreement between the majority of the predictions and actual outcome. The inter-observer agreement was also slight and intra-observer agreement ranged from slight to moderate.

CONCLUSION

We confirmed that surgeons are unable to determine the life expectancy of the implants of a THR, based on the aforementioned data, because there are other non-identified factors that affect the survivorship of a THR. For this reason, regular follow-up remains the safest way to evaluate patients' clinical picture and the evolution of radiographic changes, if there are any, in order to accurately advise patients and decide on the appropriate time for revision.

Longevity of total hip arthroplasty implants in patients with Gaucher disease

BACKGROUND

Total hip replacement (THR) is performed for arthritic hip joints, which in Gaucher disease results from osteonecrosis of the femoral head. This procedure was recommended as valid and safe for this group of patients. Nevertheless, long term outcome has not been evaluated in a large cohort.

METHODS

Data regarding all patients having hip replacement in a relatively large Gaucher clinic was collected. Specifically, details such as patient background and quality of life, implant types, radiographic signs of implant-loosening, and success of implant revision were gathered.

RESULTS

The cohort included 48 patients (females 42%, mean age at operation 42 ± 14 years), having 54 hip implants. 15 years survival was 60% and an average implant life was 12.8 years. Longevity was related to implant type, with cementless implants using ceramic-on-ceramic bearing surfaces performing better than other types (no revisions so-far). Older age at surgery also involved a lower revision risk. Gender, disease genotype, and use of cement during the procedure did not have significant effect on longevity. As expected, quality of life and hip related function were better for patients who did not undergo revision. This implies the importance of long-term implant survival.

CONCLUSION

Based on these results we recommend THR as a viable treatment for symptomatic hip arthrosis, especially at older age. Specifically, the utilisation of ceramic on ceramic bearing surfaced shows promising result in patients with Gauchers disease.

Re-revision total hip arthroplasty: Epidemiology and factors associated with outcomes

INTRODUCTION

The epidemiology of re-revision total hip arthroplasty (THA) is not yet well-understood. We aim to investigate the epidemiology and risk-factors that are associated with re-revision THA.

METHODS

288 revision THA were analyzed between 1/2012 and 12/2013. Patients who underwent two or greater revision THA were included. Hips with first-revision due to periprosthetic joint infection (PJI) were excluded. Failure was defined as reoperation.

RESULTS

51 re-revision patients were available. Mean age was 59.6 (±14.2 years), 32 (67%) females, average BMI of 28.8 (±5.4), and median ASA 2 (23; 55%). The most common re-revision indications were acetabular component loosening (15; 29%), PJI (13; 25%) and instability (9; 18%). The most common indications for first revision in the re-revision population were acetabular component loosening (11; 27%), polyethylene wear (8; 19%) and instability (8; 19%). There was an increased risk of re-revision failure if the re-revision involved exchanging only the head and polyethylene liner (RR = 1.792; p = 0.017), instability was the first-revision indication (RR = 3.000; p < 0.001), and instability was the re-revision indication (RR = 1.867; p = 0.038). If isolated femoral component revision was indicated during the re-revision, there was a decreased risk of failure (RR = 0.268, p = 0.046). 1-year re-revision survival was 54% (23/43).

DISCUSSION

Acetabular component loosening, instability, and PJI were the most common indications for re-revision. Revision due to instability is a recurrent problem that leads to re-revision failure. There was a higher infection rate in the re-revision population compared to published revision PJI. A better understanding of the indications and patient factors that are associated with re-revision failures can help align surgeon and patient expectations in this challenging population.

Survival and revision causes of hip resurfacing arthroplasty and the Mitch proximal epiphyseal replacement: results from the Danish Hip Arthroplasty Register

Background and purpose - The Mitch proximal epiphyseal replacement (PER) was developed to preserve proximal femoral bone and minimize femoral neck fracture associated with hip resurfacing arthroplasty (HRA). We studied the survival and risk of revision of HRA compared with cementless metal-on-polyethylene (MoP) total hip arthroplasty (THA) and the survival and risk of revision of the Mitch PER compared with MoP THA.Patients and methods - Using propensity score, we matched 1,057 HRA to 1,057 MoP THA and 202 Mitch PER to 1,010 MoP THA from the Danish Hip Arthroplasty Register. To estimate the relative risk (RR) of revision, we used regression with the pseudo-value approach and treated death as a competing risk.Results - The cumulative incidence for any revision of HRA at 10 years' follow-up was 11% (95% confidence interval [CI] 9.1-13) and 6.4% (CI 5.8-7.0) for MoP THA. The RR of any revision was 1.5 (CI 1.1-2.1) for HRA at 10 years' follow-up. By excluding the ASR components, the RR of revision at 10 years was 1.2 (CI 0.8-1.7). The cumulative incidence of revision was 9.6% (CI 4.2-18) for Mitch PER and 5.4% (CI 5.1-5.7) for MoP THA at 8 years. The RR of revision was 2.0 (CI 0.9-4.3) for Mitch PER at 8 years' follow-up.Interpretation - The HRA had increased risk of revision compared with the MoP THA. When excluding ASR, the HRA group had similar risk of revision compared with MoP THA. The Mitch PER did not have a statistically significant increased risk of revision compared with MoP THA.

To cement or not to cement acetabular cups in total hip arthroplasty: a systematic review and re-evaluation

INTRODUCTION

Total Hip Arthroplasty (THA) in the treatment of primary osteoarthritis of the hip has evolved to a very safe and cost-effective intervention with revision rates below 5% after 10 years. To this day, however, controversy remains on whether or not to cement the acetabular cup.

METHODS

A comprehensive PubMed search of the English literature for studies published between 2007 and 2018 was performed. Studies comparing the clinical (revision rate, functionality), radiological (wear) or economic (cost) differences between cemented (cemented stem with cemented cup) and hybrid (cemented stem with uncemented cup) prostheses for primary osteoarthritis of the hip were identified as eligible.

RESULTS

A total of 1032 studies were identified whereof twelve were included for qualitative synthesis. All studies concerning the risk of revision were based on registry data, covering a total of 365,693 cups. Cemented prostheses had a similar or lower risk of revision compared to hybrid prostheses in every study, but performed slightly worse on functionality and quality of life. While cemented prostheses were the cheapest option, hybrids were the most cost-effective.

DISCUSSION

The widespread preference for cementless fixation of the acetabulum cannot be explained by a superior survival of cementless or hybrid models. Irrespective of age, cemented fixation of the acetabulum remains the gold standard to which other techniques should be compared.

In Vitro Performance of Bioinspired Phenolic Nanocoatings for Endosseous Implant Applications

In the quest for finding new strategies to enhance tissue integration and to reduce the risk of bacterial colonization around endosseous implants, we report the application of auto-oxidative phenolic coatings made of tannic acid and pyrogallol to titanium surfaces. The functionalized surfaces were screened for their biological performance using cultures of primary human osteoblasts and biofilm-forming bioluminescent staphylococci S. epidermidis Xen43 and S. aureus Xen29. No toxic effect of the coatings on osteoblasts was detected. While tannic acid coatings seemed to induce a delay in osteoblast maturation, they revealed anti-inflammatory potential. Similar effects were observed for pyrogallol coatings deposited for 24 h. Thin pyrogallol coatings deposited for 2 h seemed to promote osteoblast maturation and revealed increased calcium deposition. The effects on osteoblast were found to be related to the release of phenolic compounds from the surfaces. While the phenolic coatings could not inhibit staphylococcal biofilm formation on the titanium surfaces, released phenolic compounds had an inhibitory effect the growth of planktonic bacteria. In conclusion, the assessed coating systems represent a versatile functionalization method which exhibit promising effects for endosseous implant applications.

The what, when and how of orthopaedic registers: an introduction into register-based research

Establishment of orthopaedic registers started in 1975 and many registers have been initiated since. The main purpose of registers is to collect information on patients, implants and procedures in order to monitor and improve the outcome of the specific procedure.

Data validity reflects the quality of the registered data and consists of four major aspects: coverage of the register, registration completeness of procedures/patients, registration completeness of variables included in the register and accuracy of registered variables.

Survival analysis is often used in register studies to estimate the incidence of an outcome. The most commonly used survival analysis is the Kaplan–Meier survival curves, which present the proportion of patients who have not experienced the defined event (e.g. death or revision of a prosthesis) in relation to the time. Depending on the research question, competing events can be taken into account by using the cumulative incidence function. Cox regression analysis is used to compare survival data for different groups taking differences between groups into account.

When interpreting the results from observational register-based studies a number of factors including selection bias, information bias, chance and confounding have to be taken into account. In observational register-based studies selection bias is related to, for example, absence of complete follow-up of the patients, whereas information bias is related to, for example, misclassification of exposure (e.g. risk factor of interest) or/and outcome.

The REporting of studies Conducted using Observational Routinely-collected Data guidelines should be used for studies based on routinely-collected health data including orthopaedic registers.

Linkage between orthopaedic registers, other clinical quality databases and administrative health registers may be of value when performing orthopaedic register-based research.

Cite this article: EFORT Open Rev 2019;4 DOI: 10.1302/2058-5241.4.180097

Impact of hip arthroplasty registers on orthopaedic practice and perspectives for the future

Total hip arthroplasty (THA) registers are established in several countries to collect data aiming to improve the results after THA. Monitoring of adverse outcomes after THA has focused mainly on revision surgery, but patient-reported outcomes have also been investigated.Several surgery-related factors influencing the survival of the THA have been thoroughly investigated and have changed clinical practice. These factors include surgical approach, specific implants, the size of the components, type of fixation and different bone cements.Register data have been used to examine the risk of venous thromboembolism and bleeding after THA. These investigations have resulted in shorter duration of thromboprophylaxis and a reduced frequency of blood transfusion.Registers may provide specific information to surgeons on the outcome of all THAs that they have performed with a detailed analysis of revisions rates and reasons for the revisions.A number of other stakeholders can use register data to provide benchmarks. The National Joint Registry for England, Wales, Northern Ireland and the Isle of Man supplies data to the Orthopaedic Device Evaluation Panel (ODEP), which provides benchmarks at 3, 5, 7, 10, and 13 years graded from A*, A, B and C.Future perspectives: National registers have to play a major role in documenting the quality of THA in order to describe best practice and report implant outliers. The registers have to be used for research and post-market surveillance and register data may be a source for intelligent decision tools. Cite this article: EFORT Open Rev 2019;4 DOI: 10.1302/2058-5241.4.180091.

Risk factors for early revision after total hip and knee arthroplasty: National observational study from a surgeon and population perspective

Aims

To identify predictors of early revision (within 3 years of the index operation) for hip and knee replacement (HR, KR) from both surgeon and population perspectives.

Patients and methods

Hierarchical logistic regression on national administrative data for England for index procedures between April 2009 and March 2014.

Results

There were 315,273 index HR procedures and 374,530 index KR procedures for analysis. Three-year revision rates were 2.1% for HR and 2.2% for KR. The highest odds ratios for HR were for 3+ previous emergency admissions, drug abuse, Parkinson’s disease, resurfacing and ages under 60; for KR these were patellofemoral or partial joint replacement, 3+ previous emergency admissions, paralysis and ages under 60. Smaller effects were found for other comorbidities such as obesity (HR) and diabetes (KR). From a population perspective, the only population attributable fractions over 5% were for male gender, uncemented total hip replacements and partial knee or patellofemoral replacements.

Conclusions

Meeting the rising demand for revision surgery is a challenge for healthcare leaders and policymakers. Our findings suggest optimising patients pre-operatively and improving patient selection for primary arthroplasty may reduce the burden of early revision of arthroplasty. Our study gives useful information on the additional risks of various comorbidities and procedures, which enables a more informed consent process.

Clinical relevance

Surgeons should make patients with certain risk factors such as age and procedure type aware of their higher revision risk as part of shared decision-making.

The effect of surface immobilized NBD peptide on osteoclastogenesis of rough titanium plates in vitro and osseointegration of rough titanium implants in ovariectomized rats in vivo

Successful osseointegration in dental implants depends on balanced activation of osteoclasts and osteoblasts. Osteoporosis up-regulates osteoclast activity, so it is desirable to find effective interventions to inhibit osteoclastogenesis and enhance the osseointegration of implants under these conditions. It has been reported that the NF-κB essential modulator (NEMO)-binding domain (NBD) peptide can prevent osteoclast formation and bone resorption. In this study, we conjugated NBD peptide onto the surface of rough pure titanium (Ti) using the layer by layer technique. We analyzed the surface characteristics and determined the successful NBD integration by the presence of trivial granular structures, increased S elements and hydrophilia. Importantly, we first reported that Ti surface-conjugated NBD peptide retained its inhibitory effects on osteoclastogenesis by reducing osteoclast sealing zone formation and function. These effects were mediated by a reduction in NFATc1 expression, which in turn regulated integrin ανβ₃ and MMP9 by targeting the P65 signaling pathway. In vivo TRAP staining suggested NBD-coating decreased osteoclast formation with less pseudopodia. Micro-CT and histomorphometric analysis demonstrated that NBD-coating enhanced pronounced osseointegration in vivo in ovariectomized rats. This study holds great promise for in vivo use of immobilized NBD peptide and offers an effective therapeutic approach to select more suitable Ti-implant surface modifications for improving implant osseointegration in osteoporotic patients.

Successful osseointegration in dental implants depends on balanced activation of osteoclasts and osteoblasts.

Thirty-five-year Trends in First-time Hospitalization for Hip Fracture, 1-year Mortality, and the Prognostic Impact of Comorbidity: A Danish Nationwide Cohort Study, 1980-2014

BACKGROUND

We examined trends in hip fracture incidence in Denmark from 1980 to 2014, trends in subsequent 1-year mortality, and the prognostic impact of sex, age, and comorbidity.

METHODS

This nationwide cohort study prospectively collected data from population-based Danish registries. We included 262,437 patients with incident hip fracture and assessed comorbidity using the Charlson Comorbidity Index (CCI).

RESULTS

Despite slight increases in incidence rates (IRs) of hip fracture up to the mid-1990s, the annual IR decreased by 29% from 1980 to 2014 in women but remained stable in men. Decrease affected all age groups. IR decreased in patients without comorbidity but increased with increasing comorbidity (13% in patients with moderate and 510% in patients with very severe comorbidity). Adjusted mortality rate ratios (MRRs) following hip fracture in 2010-2014 compared with 1980-1984 were 0.68 (95% confidence interval [CI] = 0.65, 0.71) within 30 days and 0.63 (95% CI = 0.61, 0.66) within 31-365 days. The mortality decreased up to 40% irrespective of comorbidity. Compared with patients with no comorbidity, those with very severe comorbidity had adjusted MRRs of 2.48 (95% CI = 2.39, 2.56) and 2.81 (95% CI = 2.74, 2.88) within 30 days and 31-365 days post-hip fracture, respectively.

CONCLUSIONS

Although the incidence rate of hip fracture increased substantially with increasing comorbidity, the following 1-year mortality decreased by 40% from 1980 through 2014 irrespective of sex, age, and comorbidity level, suggesting improvement in both treatment and rehabilitation of patients with hip fracture. Comorbidity burden was, however, a strong prognostic factor for 1-year mortality after hip fracture.

Early Failure of Primary Total Hip Arthroplasty: Is Surgical Approach a Risk Factor?

BACKGROUND

In an era of innovation in surgical approaches for total hip arthroplasty (THA), there is concern for increasing trends of early failure. The purpose of this study is to evaluate the incidence of early failure of primary THA stratified by surgical approach.

METHODS

A retrospective review was performed on consecutive primary THAs completed from 2007 to 2014 at a high-volume center. THAs were stratified by surgical approach. Only the direct anterior (DAA) and posterior approaches (PA) were included. The primary outcome measure was early revision (<5 years). Descriptive statistics were performed using SAS software.

RESULTS

In total, 6894 primary THAs performed between 2007 and 2014 were included. Across 2431 DAA THAs and 4463 PA THAs, there were 103 revisions overall. There was no difference in the overall revision rate for DAA THAs (1.69%) compared to PA THAs (1.39%) (P = .33). The DAA had a higher rate of early revisions for femoral component loosening compared to the PA (P = .0003). About 35.7% of DAA THAs were revised for femoral loosening compared to 8% for the PA (P = .0003). Early failure by femoral loosening occurred more often via the DAA in Dorr A bone (P = .03). The PA had a higher incidence of revision for instability (P = .04). There was no difference in modes of failure with regards to time to failure, acetabular loosening, early periprosthetic fracture, or infection.

CONCLUSION

The DAA had a higher incidence of femoral loosening while PA had a higher mode of failure due to instability. Overall revision rates were not statistically different between approaches.

Trochanteric Bursitis Following Primary Total Hip Arthroplasty: Incidence, Predictors, and Treatment

BACKGROUND

Trochanteric bursitis (TB) remains a common complication after total hip arthroplasty (THA), with an incidence between 3% and 17%, depending on the surgical approach, with the posterior approach (PA) being relatively protective compared to the lateral approach. The purposes of this study were to determine the incidence of TB after primary THA, identify potential risk factors for TB, and examine the utility of different modes of treatment.

METHODS

Retrospective cohort data of 990 primary THAs performed in a single institution, including 613 PAs and 377 direct anterior approaches (DAAs), were analyzed. Data abstracted included demographic data, operative diagnosis, comorbidities, radiographic assessment, and other specific predictors of interest that were compared between patients diagnosed with TB following THA and controls.

RESULTS

The incidence of TB following primary THA was 5.4% (54/990) for the entire cohort. The incidence did not differ significantly between the PA and DAA (5% vs 6.1%, respectively; P = .47). Charlson comorbidity index and American Society of Anesthesiology did not differ significantly in the TB group. Lumbar spinal stenosis and history of past smoking were significantly more common in patients who developed TB (P = .03, P = .01, respectively), but did not continue to be significant risk factors on multivariate analysis. All patients were treated nonoperatively by the time of final follow-up. Seventy-four percent required a local steroid injection and 30% required treatment with more than one modality.

CONCLUSION

The occurrence of TB is not influenced by the surgical approach (PA or DAA), and could not be predicted by specific comorbidities or radiographic measurements. However, it can be effectively treated conservatively in most cases.

Increasing Burden of Total Hip Arthroplasty Revisions in Patients Between 45 and 64 Years of Age

BACKGROUND

This study provides a comprehensive analysis of total hip arthroplasty (THA) revisions in the U.S. from 2007 to 2013.

METHODS

International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes were used to identify all THA revisions in the Nationwide Inpatient Sample (NIS) from 2007 to 2013. The diagnoses leading to the revisions, types of revisions, major inpatient complications, and hospital and patient characteristics were compared between 2007 and 2013. Multivariable logistic regression models were used to calculate adjusted odds ratios (ORs) for complications in 2013 versus 2007.

RESULTS

This study identified 320,496 THA revisions performed between 2007 and 2013. From 2007 to 2013, the THA revision rate adjusted for U.S. population growth increased by 30.4% in patients between 45 and 64 years of age and decreased in all other age groups. The rate of surgically treated THA dislocations decreased by 14.3% from 2007 to 2013 (p < 0.0001). The mean length of the hospital stay and hospital costs for THA revision were significantly lower in 2013 than in 2007 (4.6 versus 5.8 days and $20,463 versus $25,401 both p < 0.0001). A multivariable model showed that the odds of a patient undergoing THA revision having the following inpatient complications were significantly lower in 2013 than in 2007: deep vein thrombosis (OR = 0.57, p = 0.004), pulmonary embolism (OR = 0.45, p = 0.047), myocardial infarction (OR = 0.52, p = 0.003), transfusion (OR = 0.64, p < 0.0001), pneumonia (OR = 0.56, p < 0.0001), urinary tract infection (OR = 0.66, p < 0.0001), and mortality (OR = 0.50, p = 0.0009). Notably, the odds of being discharged to a skilled nursing facility were also lower in 2013 than in 2007 (OR = 0.71, p < 0.0001).

CONCLUSIONS

The THA revision rate has significantly increased in patients between 45 and 64 years of age. However, the rate of surgically treated THA dislocations has decreased significantly. This may indicate that evolving techniques and implants are improving stability. The rate of inpatient complications following THA revision also decreased significantly from 2007 to 2013.

LEVEL OF EVIDENCE

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

Season of the year influences infection rates following total hip arthroplasty

AIM

To research the influence of season of the year on periprosthetic joint infections.

METHODS

We conducted a retrospective review of the entire Medicare files from 2005 to 2014. Seasons were classified as spring, summer, fall or winter. Regional variations were accounted for by dividing patients into four geographic regions as per the United States Census Bureau (Northeast, Midwest, West and South). Acute postoperative infection and deep periprosthetic infections within 90 d after surgery were tracked.

RESULTS

In all regions, winter had the highest incidence of periprosthetic infections (mean 0.98%, SD 0.1%) and was significantly higher than other seasons in the Midwest, South and West (P < 0.05 for all) but not the Northeast (P = 0.358). Acute postoperative infection rates were more frequent in the summer and were significantly affected by season of the year in the West.

CONCLUSION

Season of the year is a risk factor for periprosthetic joint infection following total hip arthroplasty (THA). Understanding the influence of season on outcomes following THA is essential when risk-stratifying patients to optimize outcomes and reduce episode of care costs.

Reducing cost drivers in total joint arthroplasty: understanding patient readmission risk and supply cost

Introduction: Understanding and planning for the factors that impact supply cost and unplanned readmission risk for total joint arthroplasty (TJA) patients is helpful for hospitals at financial risk under bundled payments. Readmission and operating room supply costs are two of the biggest expenses. Methods: Logistic and linear regressions are used to measure the impacts of TJA patient attributes on readmission risk and supply costs, respectively. Results: Patients' health market segment and the number/type of comorbidity impacts 30/90-day readmission rates. Surgeon implant preference and type of surgery impact supply costs. Discharge location and two of the five health market segments increase the odds of 30-day readmission. Arrhythmia and lymphoma are the primary comorbidities that impact the odds of readmission at 90 days. Conclusions: Preoperatively identifying TJA patients likely to have large supply costs and higher readmission risk allows hospitals to invest in low-cost interventions to reduce risk and improve healthcare value.

The frail fail: Increased mortality and post-operative complications in orthopaedic trauma patients

OBJECTIVE

The burgeoning elderly population calls for a robust tool to identify patients with increased risk of mortality and morbidity. This paper investigates the utility of the MFI as a predictor of morbidity and mortality in orthopaedic trauma patients.

DESIGN

Retrospective review of the NSQIP database to identify patients age 60 and above who underwent surgery for pelvis and lower extremity fractures between 2005 and 2014.

MAIN OUTCOMES AND MEASURES

For each patient, an MFI score was calculated using NSQIP variables. The relationship between the MFI score and 30-day mortality and morbidity was determined using chi-square analysis. MFI was compared to age, American Society of Anesthesiologists physical status classification, and wound classifications in multiple logistic regression.

RESULTS

Study sample consisted of 36,424 patients with 27.8% male with an average age of 79.5 years (SD 9.3). MFI ranged from 0 to 0.82 with mean MFI of 0.12 (SD 0.09). Mortality increased from 2.7% to 13.2% and readmission increased from 5.5% to 18.8% with increasing MFI score. The rate of any complication increased from 30.1% to 38.6%. Length of hospital stay increased from 5.3days (±5.5days) to 9.1days (±7.2days) between MFI score 0 and 0.45+. There was a stronger association between 30-day mortality and MFI (aOR for MFI 0.45+: 2.6, 95% CI: 1.7-3.9) compared to age (aOR for age: 1.1, 95% CI: 1.1-1.1) and ASA (aOR 2.5, 95% CI: 2.3-2.7).

CONCLUSIONS AND RELEVANCE

MFI was a significant predictor of morbidity and mortality in orthopaedic trauma patients. The use of MFI can provide an individualized risk assessment tool that can be used by an interdisciplinary team for perioperative counseling and to improve outcomes.

Age and Early Revision After Primary Total Hip Arthroplasty for Osteoarthritis

Prior reports have noted an increased risk of early revision among younger patients undergoing total hip arthroplasty (THA) but have been confounded by the inclusion of various diagnoses. The purpose of this study was to assess the revision rate and the time to revision for patients undergoing THA for osteoarthritis based on age. Patients with a diagnosis of osteoarthritis who underwent both primary and revision THA at the same institution were identified. The time between primary and revision surgery and the indication for revision were collected. Patients were stratified into 2 groups based on age at the time of primary THA: 64 years or younger (group 1) or 65 years or older (group 2). Between 1996 and 2016, a total of 4662 patients (5543 hips) underwent primary THA for a diagnosis of osteoarthritis. Of these, 100 patients (104 hips) received a revision THA (62 in group 1 and 42 in group 2). Mean age was 52.7±8.4 years in group 1 vs 73.4±6.3 years in group 2 (P<.001). There was no significant difference in mean body mass index (29.7±7.3 kg/m² vs 28.4±4.6 kg/m², P=.30). Rate of revision was not significantly different between the groups (1.8% vs 2.0%, P=.7). Average time from primary to revision surgery was 3.0±3.2 years for group 1 and 1.1±2.1 years for group 2 (P=.001). Among patients undergoing primary THA for a diagnosis of osteoarthritis, younger age is not associated with an increased rate of early failure or revision. [Orthopedics. 2017; 40(6):e1069-e1073.].