HIP International

This study aimed to compare the biomechanical performance of cups implanted with manual versus robotic reaming, single versus sequential reaming, as well as no screws, 1 screw and 2 screws.

A total of 48, 56-mm diameter 3D-printed porous acetabular cups were impacted into separate polyurethane foam bone models reamed with either manual or robotic arm reaming, and either single or sequential reaming techniques. Simultaneous torsion-compression loading yielded torque at failure, angular displacement at failure and torsional stiffness of acetabular cups fixed with either 0, 1 or 2 acetabular screws.

Overall, torsional stiffness for robotically-reamed cups (both sequential and single) was 45% higher than those reamed via manual instrumentation (3609.0 vs. 2484.6 N·m/rad; p < 0.0001). With increasing number of acetabular screws, the torque at failure (zero screws: 60.1 N·m vs. 1 screw 67.0 N·m vs. 2 screws 97.9 N·m; p < 0.001) and angular displacement at failure (0 screws: 2.0° vs. 1 screw 1.7° vs. 2 screws 5.3°; p < 0.001) increased. There was no difference in the torque, angular displacement at failure or torsional stiffness observed between cups reamed via single or sequential reaming (all p > 0.05). Neither torque nor angular displacement showed differences at failure (all p > 0.05).

Robotically-reamed cups demonstrated nearly 50% greater torsional stiffness than those reamed manually, suggesting that robotic reaming results in fewer deviations in sphericity, thereby optimising the congruency of the acetabulum-cup interface.

Preoperative templating in Total Hip Arthroplasty (THA) is an essential tool in arthroplasty surgery. This study investigates the efficacy of CT-based templating in robotic total hip arthroplasty (rTHA) compared to traditional 2D digital x-ray templating and evaluates intra-observer variability among 3 arthroplasty consultants.

A total of 37 patients scheduled for primary hybrid rTHA using the Mako robot (Stryker) were included in the study. Independent, 2D digital templating (Materialise Orthoview) was performed by 3 experienced orthopaedic arthroplasty consultants, and the results were compared with a CT templating system (Stryker) and the postoperative implant size after CT based rTHA. Intra-observer reliability among the surgeons was determined using Fleiss’ Kappa, individual surgeons were compared to the CT-templating system and the postoperative implant using Cohen’s Kappa.

Intra-observer reliability among surgeons was low, with significant variability and no variable showing strong agreement. 2D digital templating demonstrated poor predictive value for the post-operative implant size. There was considerable variance between surgeons and their agreement with the CT demonstrated superior predictive values for the postoperative implants as compared to the 2D digital templating technique.

This study suggests that the predictive value of the CT templating system was superior to that of surgeon based 2D digital templating for CT templating based rTHA.

10 years after changing our institution’s total hip arthroplasty (THA) preoperative antibiotic prophylactic protocol by adding gram-negative (GN) coverage, this study aimed to assess the impact of adding GN specific coverage (GNSC) prior to THA on periprosthetic joint infection (PJI) rates.

This was a retrospective case-control study of 14,598 patients who underwent primary, elective THA between July 2012 and January 2022, with minimum 1-year follow-up. All patients were under perioperative antibiotic protocol that included GNSC with either weight-based gentamicin or aztreonam (+GNSC) and were compared to a historical control group of patients for which the antibiotic prophylactic protocol did not include GNSC (-GNSC). PJI and nephrotoxicity rates, as well as the severity of nephrotoxicity according to the RIFLE criteria, were compared between the study populations and 4122 controls.

Proportions of GN-related PJIs among culture-positive (13.70 vs. 26.53%, p = 0.076) and all PJIs (10.64 vs. 26.53%, p = 0.014) were lower for +GNSC patients, while the proportion of PJIs caused by a gram-positive bacteria were similar between groups (87.67 vs. 83.67%, p = 0.532). While the +GNSC group have significantly higher rates of nephrotoxicity (2.87 vs. 1.78%, p = 0.003), the rates of kidney injury (0.39 vs. 0.39%, p = 0.998) and kidney failure (0.17 vs. 0.16%, p = 0.567), which are the two more severe forms of nephrotoxicity, were comparable between the groups.

The addition of gentamicin or aztreonam prior to THA reduces the incidence of GN-related PJIs. Increased nephrotoxicity rates were limited to the mildest form, usually associated with reversibility and favourable outcomes.

In total hip arthroplasty (THA), the direct anterior approach (DAA) has gained popularity due to reported superior early outcomes compared to the posterior approach (PA). The aim of this study was to compare the outcomes of the DAA and PA in patients undergoing primary THA at midterm follow-up, with a secondary comprehensive analysis of the clinically important thresholds.

Data were retrospectively reviewed for patients who underwent a primary THA from 2009 to 2018. Patients were included if they had completed postoperative patient-reported outcome (PRO) scores at a minimum of 5-year follow-up or had a documented endpoint. Patients were divided into 2 groups based on the approach and propensity-matched 1:1 based on age, use of robotic assistance, sex, and body mass index. The analysis also included comparisons of clinically significant thresholds, complications, and revision rates.

176 hips were matched in each group. Both the DAA and PA groups demonstrated significant and comparable improvement across all PROs from the preoperative baseline to the midterm follow-up time point. Both groups also demonstrated comparable midterm outcomes across all PROs. Comparable (p > 0.05) rates of achieving PASS and MCID were observed. The overall complication rate was significantly higher in the PA group (p < 0.05).

Both groups reported positive outcomes at a minimum 5-year follow-up. Both groups achieved comparable midterm outcomes across all PROs and reached clinically significant thresholds at comparable rates. Moreover, the DAA group faced a lower risk for complications, which should be taken into consideration when deciding on a surgical approach.

We investigated 15-year patient-reported outcomes (PROMs) and their predictors in primary total hip arthroplasty (THA) for osteoarthritis using a cemented flanged cup and stem from a regional joint registry in New Zealand. Regional data were collected for all primary THAs with this cemented combination from 1 January 2003 to 30 June 2023 who had recorded PROMs on at least 1 occasion (n = 263). PROMs included Oxford Hip Score, Western Ontario and McMaster Universities Arthritis Index and Veterans Rand-12, evaluated against patient age, ethnicity, sex, body mass index (BMI), funding pathway, and American Society of Anesthesiologists (ASA) rating.

Significant improvements across preoperative PROMs were noted 1-year post-surgery, with a mean change above 23 in the Oxford Hip Score maintained at 5, 10, and 15 years (p ⩽ 0.001).

Regression analysis indicated that being female, public funding, and higher BMI were associated with worse preoperative PROMs. Poorer preoperative scores, older age and ASA 3 rating correlated with poorer postoperative outcomes.

Most of the current evidence for short femoral stems in total hip arthroplasty (THA) is related to uncemented fixation. This study aims to summarise the existing evidence on the use of short cemented stems in THA, with a focus on overall implant survival, clinical outcomes, radiographic findings, and complication rates.

A systematic literature review was conducted following the PRISMA guidelines. 12 articles met the inclusion criteria. The risk of bias was assessed through the Methodological Index for Non-Randomized Studies (MINORS) score.

With a total of 5294 total hip replacement performed, the mean follow-up was 13.5 years. The most reported complications were dislocation, periprosthetic fracture, and infections; several studies reported varus and valgus stem malalignment. All the included studies demonstrated improved clinical outcomes.

Short cemented stems are a reliable option for Dorr type A femurs, as well as for hypoplastic and small femurs. Their advantages include preservation of metaphyseal bone, easier insertion, and easier removal in case of revision. Varus and valgus stem-position should be studied as risk factors for failure. Despite small follow-up available, and considering different stem type and length, cemented short stems implants are a safe and effective option for THA.

Short stems in total hip arthroplasty (THA) have the potential to improve periprosthetic bone preservation compared to conventional stems due to a more anatomical distribution of biomechanical force. This study is a follow-up study of a randomised controlled trial using ultra-short and conventional stems in THA with the aim to investigate the long-term changes in periprosthetic bone mineral density (BMD) at 6 and 10 years post-THA.

A cohort of 51 patients with hip osteoarthritis were randomized to either an ultra-short stem (n = 26) or a conventional stem (n = 25) group. Periprosthetic BMD was measured at 6- and 10-years post-surgery. Primary endpoint was BMD changes in Gruen zones 1 and 7. Lumbar spine, L1-4, BMD was used as an indicator of overall bone loss. Clinical outcome scores and BMD changes in Gruen zone 1-7 were used as secondary endpoints.

37 hips, 17 ultra-short stems and 20 conventional stems, were followed up until 10 years. At 6- and 10-years post-THA, the ultra-short stem group had less periprosthetic BMD reduction compared to the conventional stem group in Gruen zone 1; mean differences (%) were -17.6 (CI, -23.4–-10.6) and -18.3 (CI, -28.0–-9.0), respectively (p < 0.001). There was similar BMD loss in Gruen zone 7 and zones 1–7 between groups. Compared to overall bone loss, the ultra-short stem group lost less BMD than the conventional group. Adverse events and clinical outcomes did not differ between groups.

Over a 10-year follow-up, THA using an ultra-short stem exhibited significantly reduced periprosthetic BMD loss in Gruen zone 1 compared to the conventional stem but this did not result in better clinical results. The observed preservation of bone density suggests potential long-term advantages of the ultra-short stem in minimising stress shielding and maintaining periprosthetic bone quality.

ClinicalTrials.gov registration (number NCT01319227)

There is increased awareness of socioeconomic disparities among total hip arthroplasty (THA) patients. Most studies contain small sample sizes and few control for confounding variables. This study aims to evaluate postoperative outcomes and survivorship after THA in patients of different races/ethnicities.

Patients who underwent a primary THA were identified in the New York Statewide Planning and Research Cooperative System (SPARCS) database. Patients were stratified into 4 groups: White, Black, Hispanic, or Asian. Categorical variables and continuous variables were compared, and revision free survival was calculated using Kaplan Meier survival analysis. Multivariate Cox proportional hazard regression was used to calculate revision hazard ratios.

In total, 203,443 White, 19,282 Black, 11,669 Hispanic, and 2179 Asian patients were identified. Length of stay, discharge disposition, postoperative anaemia, blood transfusions, 3-month re-admissions and emergency room visits, and 3- and 12-month periprosthetic joint infection rates were all higher in Black and Hispanic patients compared to White (p < 0.001, p < 0.001, p < 0.001, p < 0.001, p = 0.014, p = 0.003, respectively); however, 12-month mortality rates were similar. Cox proportional hazard regression analysis demonstrated that Black patients had a lower risk of revision compared to White patients (HR 0.90; 95% CI, 0.82–0.98, p = 0.021). There were no significant differences in the cumulative revision event rate up to 10 years postoperatively.

Non-White patients are significantly more likely to have worse short-term outcomes and complications. However, overall rates of revision at 1 year are similar across these groups, with a slightly lower rate of revision in Black patients after controlling for confounding factors.

Although the Burch-Schneider antiprotrusio cage (BS-APC) has been reported to be reliable, long-term data for this implant are scarce. We thus aimed to investigate survival and radiological results for revision total hip arthroplasty with the BS-APC in patients with major bone deficiency (55% AAOS defect grade 3, 39% grade 4) who had a minimum follow-up of 5 years (mean 10.2 years).

144 revisions in 140 patients were performed due to aseptic loosening (n = 74), infection (n = 50), or other reasons (n = 20). Survival analysis was performed with death as a competing risk. Clinical follow-up was performed at 1, 2, and 5 years and every 5 years thereafter.

77 patients died during follow-up, 25 within the first 5 years. 12 BS-APCs were re-revised for infection (n = 5), aseptic loosening (n = 5), or instability (n = 2). The cumulative incidence for aseptic re-revision of BS-APCs was 4.3% at 10 years (95% CI, 1.8–10.1%), and the cumulative risk of death was 73.3% (95% CI, 62.4–83.2%). Radiological changes occurred in 26 of 87 radiologically examined hips, of which 8 cases were revised.

We found excellent mid- and long-term survival of the BS-APC in acetabular revision with major bone deficiencies, in accordance with or superior to most literature reports, which might be explained by strict adherence to surgical technique.

The question of choosing a treatment strategy for acetabular bone loss remains relevant. The aim of this study was to evaluate the clinical and radiological results of the footing technique in patients who underwent revision total hip arthroplasty (rTHA).

The study included 36 patients (37 hips). The mean follow-up was 3.1 years. Acetabular defects as per the Paprosky classification type 3B were in 34 hips, type 3B and pelvic discontinuity were in 3 hips. Half cage was used in addition to footing technique in 9 hips.

Aseptic loosening was observed in 2 hips, and dislocations were observed in the other 2 hips. At a mean follow-up of 3.1 years, cup and augment construct survival was 94.6% with aseptic loosening as the endpoint. Improvement in postoperative functional results was established. Good ability to restore the hip rotation centre and to restore limb length according to radiographs were noted.

The footing technique shows good clinical and radiographic results in patients who have 3B acetabular defects. The use of a half cage in addition to the footing technique may be a good option for supplemental fixation. Further follow-up is required to evaluate long-term results.

This retrospective study aims to evaluate the outcome of cementing dual-mobility articulation into porous revision shells.

From a total of 102 revision hips between 2015 and 2021 in our revision database, we identified 47 cemented dual-mobility articulations. Indications for revision total hip arthroplasty (rTHA) included aseptic failure of acetabular shell (n = 34), infection (n = 7) and dislocation. We included patients with a cemented dual mobility articulation in a porous revision shell and a minimum of 1 year follow-up.

No complications were noted intraoperatively. There was no dislocation and no radiological signs of loosening at latest follow-up. The mean Oxford Hip Score improved from 24 (SD 13) preoperatively to 42 (SD 15) postoperatively. There was no revision and no peri-prosthetic joint infection.

Cementing a dual-mobility shell into a well-fixed porous revision shell is an appropriate technique to achieve the desired stability and orientation of the acetabular construct and restore the hip centre.

This meta-analysis aimed to evaluate the efficacy and safety of modular dual mobility (MDM) in revision hip arthroplasty.

We conducted a systematic search of databases. The primary outcome of interest was complications, while quality of life or functionality was evaluated using the Harris Hip Score (HHS) and Short Form-12 (SF-12). Data were combined using Review Manager 5.4. 9 studies (n = 648) were included.

The results indicated a statistically significant improvement in the quality of life or functionality of patients at the end of the follow-up period (standardised mean difference −1.48, 95% CI, −2.24–−0.72). The incidences of dislocation, revision, infection, aseptic loosening, and periprosthetic fracture were 8.69%, 11.92%, 11.38%, 5.69%, and 1.27%, respectively. The revision and aseptic loosening survivorship rates were 91% (95% CI, 80–96%) and 98% (95% CI 89–99%), respectively, at 36 months. Blood loss was similar among studies, while corrosion measured by cobalt-chromium levels in blood exceeded clinically relevant limits in some studies. Radiolucency around the acetabular shell, cup inclination, and anteversion were assessed.

This meta-analysis suggests that modular dual mobility is a safe and effective option for revision hip arthroplasty, with significant improvement in the quality of life of patients. However, the possibility of corrosion by modular dual mobility should be carefully monitored in selected patients.

CRD42023424561

This study aimed to compare preoperative education level, income level, and geographical birthplace between patients undergoing metal-on-metal hip resurfacing (MoM-HR) and those receiving a conventional uncemented total hip arthroplasty (THA).

All patients with osteoarthritis who underwent a MoM-HR or an uncemented THA registered in the Swedish Arthroplasty Register 1999–2014 were included (n = 15,871). National databases provided additional information on household income and the highest achieved education. 1481 MoM-HR patients were matched to 1481 uncemented THA patients based on age, sex, and Charlson comorbidity index. Odds ratios (OR) of MoM-HR surgery depending on socioeconomic variables were calculated using logistic regression analysis.

The OR of having MoM-HR surgery was lower among patients with lower education level compared to those with a university degree. Also, 37% of the MoM-HR patients had an income in the 2 highest quintiles compared to 32% of uncemented THA patients. There was no difference in accessibility of MoM-HR surgery between patients born in or outside Sweden.

In Sweden, within a universal healthcare coverage system, lower socioeconomic status in terms of education level was associated with decreased accessibility to innovative hip surgery, i.e., MoM-HR.

Due to demographic shifts and an increasing proportion of older adults at higher fracture risk, the overall burden of proximal femur fractures has risen significantly in recent years, placing a burden on patients and healthcare systems. Despite extensive research on hip fracture epidemiology and treatment, the specific influences of femoral and acetabular parameters on fracture localisation remain underexplored. This study evaluates the impact of these parameters on proximal femur fracture localisation.

This retrospective cohort study analysed data from 400 patients with proximal femur fractures, including medial and lateral femoral neck fractures (FNFs), pertrochanteric, and subtrochanteric fractures, treated at a university hospital between 2010 and 2022. Radiographic measurements of femoral head size and other morphological parameters were conducted using pre-operative pelvic radiographs. Statistical analyses included multivariate logistic regression.

A larger head-radius vertical (HRV) was associated with an increased risk of lateral FNFs (OR 1.11; p = 0.007). A lower Femoral Head Protrusion Index (FHEI) significantly increased the risk of lateral (OR 0.87; p < 0.001), pertrochanteric (OR 0.88; p < 0.001), and subtrochanteric fractures (OR 0.86; p < 0.001). Femur canal width was associated with a higher risk of pertrochanteric fractures (OR 1.17; p = 0.001), and a smaller lateral centre edge angle (LCEA) correlated with higher risks of lateral (OR 0.92; p = 0.021) and pertrochanteric fractures (OR 0.92; p = 0.018). Additionally, a higher body mass index (BMI) was significantly associated with subtrochanteric fractures (or 1.07; p = 0.020).

The study identified key variables associated with proximal femur fracture localisation. Morphological parameters such as HRV, FHEI, canal width, and LCEA, as well as BMI for subtrochanteric fractures, significantly influence fracture localisation, highlighting their importance for personalised risk assessment and preventive strategies.

Hip fractures are a priority topic while selective serotonin reuptake inhibitors (SSRI) use is increasing. Surgical outcomes over longer follow-up periods for hip fracture patients on SSRIs is unclear. The purpose of this study was to test for associations between SSRIs and post-surgical adverse events for hip fracture arthroplasty patients.

Hospital data were used to select patients who had hip fracture arthroplasty surgery in Nova Scotia, Canada from 2016 to 2022. Patients who filled an SSRI prescription (Rx) in the 180-day period prior to surgery were identified. Study outcomes were any emergency department (ED) visit, mortality, revision, and major bleeding within 180 days of discharge as well as a blood transfusion during admission. Multivariate hierarchical logistic models weighted by inverse probability treatment weights were estimated to test for associations between SSRI use and outcomes.

An SSRI prescription was filled in the 180-day pre-surgery period for (883) 29.9% of the 2946 cases. Adjusted odds ratios were higher for those on an SSRI for an ED visit (1.68 CI, 1.40–2.01; p < 0.0001), mortality (1.26 CI, 1.02–1.55; p = 0.036), revision (2.35 CI, 1.36–4.06; p = 0.0022), and bleeding event (1.48 CI 1.06–2.07; p = 0.022). Blood transfusion was statistically insignificant.

SSRI use was associated with worse outcomes for hip fracture patients for four of five study outcomes. SSRI use should be discussed prior to surgery to mitigate the likelihood of adverse events.