The effect of trunnionosis on the risk of re-revision following femoral head exchange in hip arthroplasty

BACKGROUND

Fretting corrosion at modular junctions contributes to arthroplasty failure. Currently, no evidence-based guidelines are available regarding the acceptable level of trunnion corrosion that can occur in vivo. We aimed to examine the relationship between trunnion corrosion and risk of re-revision to assist surgeons with intraoperative decision making.

METHOD

Grading by 3 independent examiners of revised and re-revised head components was performed using a modified Goldberg corrosion scale. Samples were separated into low-grade (LG) and high-grade (HG) corrosion. Mechanical testing determined the relationship between corrosion severity and pull-off strength at the head-stem junction.

RESULTS

529 retrieved femoral heads were analysed. A positive association was detected between males and HG corrosion (OR 2.07; 95% CI, 1.45-2.94; p < 0.001). No difference between the survivorship of LG and HG heads was detected (p-value = 0.247). In the re-revised sample, the first implant had a time in situ that was on average 7.97 years longer (95% CI, 5.4-10.6) than that of the subsequent re-revised femoral head. Severe corrosion on the first head was associated with a 37.5 (95% CI, 4.00-1944) fold increase of HG on the subsequent head (p < 0.001). Femoral disassembly force had a positive correlation with stem taper corrosion grade (p = 0.001).

CONCLUSIONS

A well-fixed stem with corrosion may remain in situ.

Higher intra-operative narcotic requirements and weakness with quadratus lumborum compared to paravertebral nerve block for total hip arthroplasty

BACKGROUND

This was a prospective single-blinded study comparing the peri-operative opioid consumption and motor weakness for patients undergoing total hip arthroplasty (THA) with either a Quadratus Lumborum Type 3 Nerve Block (QLB) or a Paravertebral Nerve Block (PVB).

METHODS

A consecutive cohort of patients undergoing elective anterior approach (AA) THA by a single high-volume surgeon were randomly assigned an anesthesiologist by the charge anesthesiologist. One anesthesiologist performed all QLBs, and the other six anesthesiologists performed the PVBs. Pertinent data include prospectively collected qualitative surveys from blinded medical personnel, floor nurses, and physical therapists as well as demographic information and post-operative complications.

RESULTS

Overall, 160 patients were included in the study divided equally between the QLB and PVB groups. The QLB group had a statistically higher peri-operative narcotic use (p < 0.001), greater intra-operative peak systolic blood pressure (p < 0.001) and respiratory rate (p < 0.001), and higher incidence of post-operative lower extremity muscle weakness (p = 0.040). There were no statistical group differences for floor narcotic use, post-operative hemoglobin levels or hospital length of stay.

CONCLUSION

The QLB required greater intraoperative narcotic use and resulted in greater post-operative weakness, however provided nearly equal post-operative pain management and did not adversely affect rapid discharge success.

LEVEL OF EVIDENCE

III, Non-randomized controlled cohort/follow-up study.

A Geometric Analysis of Polyethylene Liners Exposed to Acrylic-based Bone Cement

Background

Acrylic-based bone cement (polymethyl methacrylate [PMMA]) is a material commonly used in orthopaedic surgeries; however, during PMMA polymerization, a highly exothermic reaction occurs. The heat released in polymerization can damage nearby materials including poorly heat-resistant cross-linked polyethylene (XLPE). Both PMMA and XLPE are used in total hip arthroplasty and could interact during femoral stem fixation. We sought to determine if the exothermic polymerization of PMMA could alter the surface characteristics of XLPE acetabular liners.

Methods

Six XLPE liners were assigned to one of 4 experimental categories with varying volumes of PMMA applied in a manner that mimicked how the 2 materials would come into contact intraoperatively. Measurements were taken both pre- and post-intervention using a coordinate measuring machine for geometric and gravimetric analysis. Light microscopy was conducted postintervention to examine the surface for damage.

Results

Coordinate measuring machine measurements showed minimal gross deformation in all 6 liners, but there were isolated surface deposits in 4 of 6 liners. The average maximal surface deviations, when compared to the control, for liners exposed to 1 cc of cement, 2 cc of cement, or 1 cc of cement with a femoral head implant attached were 26.6 μm, 77.2 μm, and 26.4 μm, respectively. All but one liner showed an increase in volume following intervention when compared to the control. Subtle scratches were identified using light microscopy on all 6 liners.

Conclusions

XLPE shows areas of isolated surface deformation in a dose-dependent manner but with minimal gross deformation after interacting with highly exothermic PMMA.

The Use of Iodophor-Impregnated Drapes in Patients With Iodine-Related Allergies: A Case Series and Review of the Literature

Background

The use of iodophor-impregnated adhesive drapes have become almost universally incorporated into standard practice of arthroplasty draping technique. Iodine-related allergies in patients planned for joint replacement present a challenge in terms of the best course of action to minimize complications and optimize outcomes.

Methods

This is a retrospective case series of patients that received an iodophor-impregnated drape as part of draping for a total hip or knee arthroplasty at a single orthopaedic-specific hospital with documented iodine-related allergies. From 2015 to 2023, 9816 total hip arthroplasty and total knee arthroplasty cases were reviewed, and 135 were documented to have an iodine-related allergy for a prevalence of 1.38%. Intraoperative and postoperative records were reviewed to screen for an allergic reaction or wound healing issues that may have been related to an adverse reaction to the use of the iodophor-impregnated drape.

Results

Of the 135 patients, 43 had iodine listed as an allergy, 85 had shellfish, 20 had iodinated contrast media, and 3 had povidone iodine. Sixteen patients had a cluster of iodine-related allergies. There were no intraoperative reports of an allergic reaction to this drape. There were four superficial wound problems, none of which were documented to relate to an allergic dermatitis reaction, and none required further surgery.

Conclusions

Patients reporting iodine-related allergies were present in 1.38% of patients undergoing hip or knee arthroplasty in our series. We encountered no allergic reactions or adverse outcomes that could be attributed to the use of iodiphor impregnated drapes in these patients.

Lai E, Bradford L, Bass AR, Amen TB, Russell LA, Mehta B, Parks M, Figgie M, Goodman S. Racial Differences in Patient Satisfaction With the Hospital Experience Undergoing Primary Unilateral Hip and Knee Arthroplasty: A Retrospective Study

Background

Press Ganey (PG) inpatient survey is widely used to track patient satisfaction with the hospital experience. Our aim was to use the PG survey to determine if there are racial differences in overall hospital experience and perception of nurses and surgeons following hip and knee arthroplasty.

Methods

We retrospectively analyzed Black and White patients from hip and knee arthroplasty registries from a single institution between July 2010 and February 2012. The overall assessment score for the hospital experience and perception of the nurse and surgeon questions from the PG inpatient survey were dichotomized as "not completely satisfied" or "completely satisfied". Multivariable logistic regression models were developed to determine the impact of race on the likelihood of being 'completely satisfied' in the hip and knee cohorts.

Results

There were 2517 hip and 2114 knee patients who underwent surgery and completed the PG survey, of whom 3.9% were Black and 96.0% were White. Black patients were less likely to be completely satisfied with their hospital experience compared to White patients in the hip (odds ratio 0.62, confidence interval 0.39-1.00, P = .049) and knee (odds ratio 0.52, confidence interval 0.33-0.82, P = .005) cohorts. Black patients were also less likely to be completely satisfied with multiple aspects of care they received from the nurse and surgeon in both cohorts.

Conclusions

We found that the PG Survey shows Black patients were less likely to be completely satisfied than White patients with the hospital experience, including their interactions with nurses and surgeons. More work is needed to understand this difference.

Age, Sex, and Education Level Predict Telehealth Engagement in Total Joint Arthroplasty Patients

Background

Racial and other demographic predictors of total joint arthroplasty (TJA) telehealth engagement since the onset of the COVID-19 pandemic remain unclear. The purpose of the current study was to elucidate this relationship.

Methods

A retrospective, cross-sectional study on 732 primary TJA patients was conducted within a single hospital system from March 2020-December 2021 (during the pandemic). Patients were excluded if their race or education level could not be determined. Patient demographics (age, sex, body mass index, language) and TJA information were obtained. The number of telehealth visits and telehealth engagement were assessed. Engagement (yes/no) and engagement frequency across all demographics and each measure of telehealth (telemedicine, patient-reported outcome measurements [PROMs], and electronic patient portal [EPP] messaging) were analyzed using multivariate logistic and linear regression, respectively.

Results

Our results demonstrated that non-White race was not a significant predictor of binomial engagement or engagement frequency across all telehealth measures. Older age was a negative predictor of binomial engagement and engagement frequency with telemedicine and EPPs. Male sex was shown to be a negative predictor of binomial engagement with EPPs as well as PROM engagement frequency. Educational attainment of less than a college degree was a negative predictor of binomial engagement and engagement frequency with PROMs and EPPs.

Conclusions

This study demonstrates that older age, male sex, and lower education level were negative predictors of various measures of telehealth engagement. Non-White race was not a significant predictor. This data informs providers on how to improve access to virtual orthopaedic care.

An artificial intelligence framework for the diagnosis of prosthetic joint infection based on 99mTc-MDP dynamic bone scintigraphy

OBJECTIVES

Dynamic bone scintigraphy (DBS) is the first widely reliable and simple imaging modality in nuclear medicine that can be used to diagnose prosthetic joint infection (PJI). We aimed to apply artificial intelligence to diagnose PJI in patients after total hip or knee arthroplasty (THA or TKA) based on 99mTc-methylene diphosphonate (99mTc-MDP) DBS.

METHODS

A total of 449 patients (255 THAs and 194 TKAs) with a final diagnosis were retrospectively enrolled and analyzed. The dataset was divided into a training and validation set and an independent test set. A customized framework composed of two data preprocessing algorithms and a diagnosis model (dynamic bone scintigraphy effective neural network, DBS-eNet) was compared with mainstream modified classification models and experienced nuclear medicine specialists on corresponding datasets.

RESULTS

In the fivefold cross-validation test, diagnostic accuracies of 86.48% for prosthetic knee infection (PKI) and 86.33% for prosthetic hip infection (PHI) were obtained using the proposed framework. On the independent test set, the diagnostic accuracies and AUC values were 87.74% and 0.957 for PKI and 86.36% and 0.906 for PHI, respectively. The customized framework demonstrated better overall diagnostic performance compared to other classification models and showed superiority in diagnosing PKI and consistency in diagnosing PHI compared to specialists.

CONCLUSION

The customized framework can be used to effectively and accurately diagnose PJI based on 99mTc-MDP DBS. The excellent diagnostic performance of this method indicates its potential clinical practical value in the future.

KEY POINTS

• The proposed framework in the current study achieved high diagnostic performance for prosthetic knee infection (PKI) and prosthetic hip infection (PHI) with AUC values of 0.957 and 0.906, respectively. • The customized framework demonstrated better overall diagnostic performance compared to other classification models. • Compared to experienced nuclear medicine physicians, the customized framework showed superiority in diagnosing PKI and consistency in diagnosing PHI.

The anesthetic efficacy of ultrasound-guided lumbar plexus combined with quadratus lumborum block with Shamrock approach in total hip arthroplasty: study protocol for a randomized controlled trial

INTRODUCTION

The lumbar plexus originates from multiple segments of the spinal cord. Both single-level lumbar plexus block (LPB) and transmuscular quadratus lumborum block (TQLB) are commonly used to provide analgesia for the patients undergoing total hip arthroplasty (THA). However, neither of them can completely cover the lumbar plexus. Multiple-level LPB is also not recommended since this expert technique involves more potential risks. To achieve a better anesthetic effect and avoid risks, we propose to combine ultrasound-guided LPB with TQLB with Shamrock approach. We aim to assess the anesthetic efficacy of this combination technique and expect it will be an ideal alternative for conventional LPBs in THA.

METHODS AND ANALYSIS

In this prospective randomized controlled trial, 84 patients schedule for THA will be enrolled. The patients will be randomly assigned at a 1:1:1 ratio to receive LPB at L3 level (P group), T12 paravertebral block combined with LPB at L3 and L4 levels (TP group), or LPB combined with TQLB at L3 level (PQ group). Each method will be evaluated in terms of the successful rate of sensory blockade, postoperative pain, performance time of block, requirement for intraoperative sufentanil, cumulative doses of intraoperative vasoactive medications, and adverse events.

ETHICS AND DISSEMINATION

The study protocol has been approved by the institutional review board (IRB) at Shanghai Jiao Tong University Affiliated Sixth People's Hospital, China (No.2020-031). The results will be disseminated in a peer-reviewed journal and the ClinicalTrials.gov registry.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04266236 . Registered on 10 February 2020.

CLINICALTRIALS

gov PRS: Record Summary NCT04266236 .

Comparative study in vivo of the osseointegration of 3D-printed and plasma-coated titanium implants

BACKGROUND

Total hip arthroplasty is a common surgical treatment for elderly patients with osteoporosis, particularly in postmenopausal women. In such cases, highly porous acetabular components are a favorable option in achieving osseointegration. However, further discussion is needed if use of such acetabular components is justified under the condition of normal bone mass.

AIM

To determine the features of osseointegration of two different types of titanium implants [3-dimensional (3D)-printed and plasma-coated titanium implants] in bone tissue of a distal metaphysis in a rat femur model.

METHODS

This study was performed on 20 white male laboratory rats weighing 300-350 g aged 6 mo. Rats were divided into two groups of 10 animals, which had two different types of implants were inserted into a hole defect (2 × 3 mm) in the distal metaphysis of the femur: Group I: 3D-printed titanium implant (highly porous); Group II: Plasma-coated titanium implant. After 45 and 90 d following surgery, the rats were sacrificed, and their implanted femurs were extracted for histological examination. The relative perimeter (%) of bone trabeculae [bone-implant contact (BIC%)] and bone marrow surrounding the titanium implants was measured.

RESULTS

Trabecular bone tissue was formed on the 45th day after implantation around the implants regardless of their type. 45 d after surgery, group I (3D-printed titanium implant) and group II (plasma-coated titanium implant) did not differ in BIC% (83.51 ± 8.5 vs 84.12 ± 1 .73; P = 0.838). After 90 d, the BIC% was higher in group I (87.04 ± 6.99 vs 81.24 ± 7.62; P = 0.049), compared to group II. The relative perimeter of the bone marrow after 45 d did not differ between groups and was 16.49% ± 8.58% for group I, and 15.88% ± 1.73% for group II. Futhermore, after 90 d, in group I the relative perimeter of bone marrow was 1.4 times smaller (12.96 ± 6.99 vs 18.76 ± 7.62; P = 0.049) compared to the relative perimeter of bone marrow in group II.

CONCLUSION

The use of a highly porous titanium implant, manufactured with 3D printing, for acetabular components provides increased osseointegration compared to a plasma-coated titanium implant.

Epidemiological Characteristics and Trends of Primary Hip Arthroplasty in Five Tertiary Hospitals: A Multicenter Retrospective Study

OBJECTIVE

The number of primary hip arthroplasty (PHA) has increased sharply in recent years. Whether the epidemiological characteristics and trends of PHA have changed are unknown. This study aims to analyze the epidemiological characteristics and trends of those patients are urgent for public health institutions.

METHODS

The data of patients who underwent PHA in five tertiary hospitals from January 2011 to December 2020 were retrospectively reviewed. A total of 21,898 patients were included, most of whom were aged 60-69 years (25.1% males and 31.5% females). According to the hospitalization date, the patients were divided into two groups (Group A and Group B). The patients admitted between January 2011 and December 2015 were designated as Group A (7862), and those admitted between January 2016 and December 2020 were designated as Group B (14036). The patient data of the two groups, including sex, age, disease causes, body mass index (BMI), comorbidities, surgical procedures, hospital stay duration, and hospitalization costs, were analyzed by Pearson chi-Square test, Student t test or Mann-Whitney U test.

RESULTS

More women were included in Group B than in Group A (58.5% vs 52.5%, P < 0.001). The mean age of Group B was less than that of Group A (62.27 ± 14.77 vs 60.69 ± 14.44 years, P < 0.001). Femoral head necrosis was the primary pathogenic factor in both groups, with a higher proportion in Group B than in Group A (55.5% vs 45.5%, P < 0.001). Significant differences were found between the two groups in BMI, comorbidities, surgical procedures, hospital stay duration, and hospitalization costs. Total hip arthroplasty (THA) was the most common surgical procedure in both groups, with a higher proportion in Group B than in Group A (89.8% vs 79.3%, P < 0.001). The proportion of patients with one or more comorbidities was significantly higher in Group B than in Group A (69.2% vs 59.9%, P < 0.001). In addition, Group B had a shorter hospital stay duration and higher hospitalization costs than Group A.

CONCLUSION

Femoral head necrosis was the primary etiology for PHA in this study, followed by femoral neck fracture and hip osteoarthritis. Patients who underwent PHA exhibited a higher percentage of femoral head necrosis; underwent THA more often; and had larger BMIs, more comorbidities, higher medical costs, and younger age in the past decade.

Venous thromboembolism is rare after total hip and knee joint arthroplasty with long thromboprophylaxis in Finnish fast-track hospitals

INTRODUCTION

Pharmacological thromboprophylaxis effectively prevents venous thromboembolism (VTE) after total knee (TKA) and total hip arthroplasty (THA). Less is known about the influence of fast-track arthroplasty on VTE risk. We conducted a register-based study to determine the incidence of VTE after fast-track TKA and THA in Finland using long thromboprophylaxis.

MATERIALS AND METHODS

All primary TKAs and THAs operated during 2015-2016 in 3 fast-track hospitals were identified from the Finnish Arthroplasty Register. Pulmonary embolism (PE) and deep vein thrombosis (DVT) diagnosed in this patient cohort within 90 days of surgery were identified from the Finnish Hospital Discharge Register. The recommended length of thromboprophylaxis was 10 to 14 days for TKA and 28 days for THA during study period.

RESULTS

During the study period, 3 831 THAs, 4 394 TKAs and 286 bilateral TKAs (BTKAs) were performed. Of all these patients, 60% were females. Venous thromboembolism (VTE) incidence within 90 days of surgery was 0.3% (95% CI 0.2-0.4). These VTEs comprised 10 PEs and 15 DVTs. None of the VTE patients´ died within the 90-day period.

CONCLUSION

VTE incidence is low in Finnish fast-track TKA and THA patients with long thromboprophylaxis.

Five-year polyethylene cup migration and PE wear of the Anatomic Dual Mobility acetabular construct

INTRODUCTION

Dual mobility implants have been successful in reducing postoperative hip dislocation but mid-term results of cup migration and polyethylene wear are missing in the literature. Therefore, we measured migration and wear at 5-year follow-up using radiostereometric analysis (RSA).

MATERIALS AND METHODS

A cohort of 44 patients (mean age 73, 36 female) with heterogeneous indications for hip arthroplasty but all with a high risk of hip dislocation received total hip replacement (THA) with The Anatomic Dual Mobility X3 monoblock acetabular construct and a highly crosslinked polyethylene liner. RSA images and Oxford Hip Scores were obtained perioperatively and 1, 2, and 5 years postoperatively. Cup migration and polyethylene wear were calculated using RSA.

RESULTS

Mean 2-year proximal cup translation was 0.26 mm (95% CI 0.17; 0.36). Proximal cup translation was stable from 1- to 5-year follow-up. Mean 2-year cup inclination (z-rotation) was 0.23° (95% CI - 0.22; 0.68) and was greater in patients with osteoporosis compared to patients without osteoporosis (p = 0.04). Using 1-year follow-up as baseline, the 3D polyethylene wear rate was 0.07 mm/year (0.05; 0.10). Oxford hip scores improved 19 (95% CI 14; 24) points from mean 21 (range 4; 39) at baseline, to 40 (9; 48) 2 years postoperatively. There were no progressive radiolucent lines > 1 mm. There was 1 revision for offset correction.

CONCLUSIONS

Anatomic Dual Mobility monoblock cups were well-fixed, the polyethylene wear rate was low, and the clinical outcomes were good until 5-year follow-up suggesting good implant survival in patients of different age groups and with heterogeneous indications for THA.

Acetabular cup placement and offset control in robotic total hip arthroplasty performed through the modified anterolateral approach

PURPOSE

The modified anterolateral approach (Röttinger) for total hip arthroplasty (THA) offers great advantages over conventional approaches, especially concerning early postoperative symptoms, which are mild and well tolerated by patients. Robotic-assisted implantation might facilitate rapid adoption of the modified anterolateral approach without exposing surgeons to risks encountered during the learning curve. This study posits that the use of robotic assistance in conjunction with the modified anterolateral approach for total hip arthroplasty (THA) can provide a substantial enhancement in the accuracy of cup placement in comparison to manual surgery.

METHODS

Thirty-two robotic-assisted THAs met the inclusion criteria and were matched to 32 conventional cases. Acetabular cup inclination, anteversion, limb-length discrepancy, and acetabular offset were assessed using certified planning software by two independent observers using pre- and postoperative anterior-posterior radiographs. Data was analyzed for normal distribution. Chi2 test was used to determine whether implanted acetabular cups that were within Lewinnek's safe zones were influenced by type of implantation. Effect size estimates and statistical power analysis were also performed to appreciate the appropriateness of the chosen sample size.

RESULTS

Robotic-assisted implantation was found to significantly improve acetabular cup placement in terms of inclination (p < 0.001) but not anteversion (p = 0.783). Although mean postoperative limb-length discrepancy and mean acetabular offset did not differ between groups, a significantly smaller variance was found in the robotic-assisted group (p < 0.001) and (p = 0.04), respectively. There were no significant differences between the two groups in terms of consistently implanting the acetabular cup within the Lewinnek safe zones p = 0.641 for anteversion and p = 0.230 for inclination, respectively.

CONCLUSIONS

Our results show that although robotic-assisted acetabular cup implantation performed through the modified anterolateral approach did not significantly differ from conventional implantation, it did offer increased accuracy in cup positioning, acetabular bone preservation, and limb-length restoration.

Comparison of the effects of different blood conservation techniques in elderly patients undergoing total hip arthroplasty

Background

To probe into the influences of different blood conservation techniques on the postoperative coagulation function and prognosis of elderly patients receiving Total Hip Arthroplasty (THA).

Methodology

A total of 60 patients were randomly divided into Autologous Blood Transfusion (ABT) group (n=30) and ANH group (n=30). For patients in the ABT group, an autologous blood recovery machine was used to recover, wash and filter the surgical field blood. For those in the Acute Isovolumic Hemodilution (ANH) group, blood was collected preoperatively from the central vein and stored in a citrate anticoagulant blood storage bag, while the same amount of hydroxyethyl starch was injected into the peripheral vein to dilute the blood. After Mai bleeding steps of the operation were completed, the autologous blood of patients was transfused back in both groups. The clinical indicators of patients in each group were observed.

Results

48 h after operation, the ANH group obtained a higher level of hemoglobin (Hb), shorter Activated Partial Thromboplastin Time (APTT), and a lower expression rate of platelet activating factor CD62P than the ABT group.

Conclusion

The ANH group exhibits higher content of hemoglobin and fewer platelet (Plt)activating factors produced than the ABT group, while no significant difference in the shortened length of hospital stays is found.

Hip arthroplasty practice across the Organisation for Economic Co-operation and Development (OECD) over the last decade

INTRODUCTION

There are large variations in the number of hip replacements performed between countries, demonstrating large health inequalities; however, there has been limited research on this variation. The aims of this paper were to compare rates of hip replacements using Organisation for Economic Co-operation and Development (OECD) data for the period 2008-2018. The study also compared changes in the number of hip replacements in the total population and in only those aged over 65, and looked for a correlation of health expenditure and gross domestic product (GDP) with rates of hip replacements.

METHODS

The OECD collects annual data from all member countries on the numbers of hip replacements, healthcare expenditure and GDP. Data analysis was undertaken using STATA. Descriptive statistics and Pearson's correlation coefficient were performed.

RESULTS

The mean number of hip replacements performed in OECD countries in 2018 was 191.5 per 100,000 population per year. The largest number was 310.6 in Germany and the lowest was 8.6 in Mexico. There has been a 21.7% increase in the mean number of hip replacements across OECD countries. There was a moderate and significant Pearson coefficient of 0.468 (p = 0.009) between the number of hip replacements performed per 100,000 population in 2018 and GDP per person, and a strong and significant correlation with health expenditure (R = 0.784, p < 0.001). There was a moderate correlation (R = 0.645, p = 0.003) between the percentage change in the number of hip replacements performed per 100,000 population and the percentage change in healthcare expenditure per person between 2008 and 2018.

CONCLUSIONS

There is 36-fold variation in the practice of hip replacements across the OECD and the number of hip replacements has increased by more than 20% over the past decade. The number of hip replacements performed appears to be correlated with health expenditure in each country and may indicate a need that can only be met by increasing health expenditure.

Careful patient selection together with optimal implant positioning may reduce but does not eliminate the risk of elevated serum cobalt and chrome levels following metal-on-metal hip resurfacing

BACKGROUND

Elevated serum chrome (sCr) and cobalt (sCo) concentrations are associated with local tissue adverse reactions to metal debris following metal-on-metal hip resurfacing (MoM-HR). Serum metal ions <2 µg/l are probably of little clinical relevance and a pragmatic "safe" threshold <5 µg/l has been suggested.The primary aim of this study was to evaluate if a careful selection of patients combined with optimal implant positioning could eliminate cases with "unsafe" serum metal ion levels. A secondary aim was to study the association between different risk factors and having Co and/or Cr levels >5 µg/l.

PATIENTS AND METHODS

This is a retrospective, single-institution cohort study of 410 consecutive patients operated on with a Birmingham Hip Resurfacing (BHR) implant between 2001 and 2014. 288 of these had a unilateral MoM-HR, pelvic and true lateral radiographs, and a related sCo and sCr sample, and were included in the final analysis. They were allocated to either a presumed "optimal group" consisting of only men aged <60 years old, with femoral head component >48 mm diameter, and with a cup positioned within Lewinnek's safe zones, or a "suboptimal group" consisting of the remaining patients. Fisher's exact test and multiple logistic regression analyses were performed.

RESULTS

In the optimal group 48% (47/97) had serum metal ions >2 µg/l and 8% (8/97) >5 µg/l compared to 61% (116/191) and 18% (34/191) in the suboptimal group, p = 0.059 and p = 0.034 respectively. Acetabular cups with an anteversion <5 degrees had the highest odds ratio, 6.5 (95% CI, 3.0-14.3), of having sCo and sCr concentrations exceeding 5 µg/l.

CONCLUSIONS

A well oriented BHR acetabular component in a presumably "optimal" patient reduces the risk of having elevated serum metal ions but does not eliminate it. Insufficient cup anteversion seems to be the strongest associated factor of elevated serum metals.

Direct anterior approach in total hip arthroplasty: influence of stem length on clinical and radiological outcomes at medium-term follow-up

PURPOSE

To evaluate the influence of short versus long stems implanted through a Direct Anterior Approach (DAA) on clinical and radiological outcomes in THA at medium-term follow-up (average follow-up of 44.8 months).

METHODS

167 consecutive total hip arthroplasties treating patients affected by primary hip osteoarthritis were retrospectively evaluated. A standard-length stem (H-MAXs) was used in 70 patients, while a short metaphyseal-fitting femoral stem (MINIMA) was used in 97 patients. The Harris Hip Score (HHS) and Forgotten Joint Score-12 (FJS) were used as outcomes measurements. Post-operatively, Engh's score and Brooker classification were analyzed at 6 months, 1 year and every 2 years until the final FU. The correct size of the implant was evaluated determining the canal fill index (CFI), and all undersized stems were classified according to Magra classification.

RESULTS

The average HHS was 83 ± 13.4 in the standard stems group and 87 ± 14.1 for short stems group (p = 0.148). The average FJS was 87.9 ± 15.2 for patients in the standard stems group and 84.5 ± 17.7 with no significant differences (p = 0.327). None of the stems showed radiographic signs of instability (standard stems mean Engh's score: 19.25 versus short stems mean Engh's score: 19.50-p = 0.41). According to Brooker classification, no significant difference in severity was found using different stems (p = 0.715). A high rate of undersized stems was found (standard stems 24%-short stems 25%) but without statistical difference between groups (p = 0.078), while a different trend in malposition following the recent classification proposed by Magra et al. was observed evaluating all undersized stems (p = 0.0387).

CONCLUSIONS

Both groups achieved good and comparable patient-reported outcome measurements (PROMs) and radiographic stability with fixation observed by bone ingrowth. A high rate of undersized stems was found with a correlation between femoral stem length and specific pattern of malposition. Malalignment in Varus was frequent in shorter stems in contact proximally with medial calcar and distally with lateral cortex, while a uniform undersizing was observed for longer ones with a continuous margin around the stem. However, the stems never presented progressive radiolucent lines over the whole surface of the stem.

Developmental dysplasia of the hip is common in patients undergoing total hip arthroplasty under 50 years of age

INTRODUCTION

Developmental dysplasia of the hip (DDH) refers to congenital and/or developmental hip instability that can result in hip joint subluxation or dislocation. When detected neonatally, conservative treatment with hip bracing can restore normal hip anatomy. Missed detection of DDH in the neonatal period or late development of DDH often requires surgical intervention to correct the abnormal anatomy. Furthermore, despite surgical intervention, residual sequelae may persist leading to early osteoarthritis of the hip joint requiring joint replacement surgery.

AIM

This study investigates the prevalence of hip dysplasia in patients undergoing total hip arthroplasty (THA) under 50 years of age.

METHODS

The hip arthroplasty database at a national referral centre was investigated from January 2014 to December 2020. In patients under 50 years of age, those with an adequate pre-operative anteroposterior pelvic radiograph without previous hip arthroplasty were included, while those with inadequate radiographs were excluded. The following measurements were made on the contralateral non-operated hip: (1) lateral centre-edge angle (LCEA), (2) Tönnis angle, (3) acetabular version, (4) acetabular depth, (5) femoral head lateralisation, (6) femoral head extrusion index, and (7) acetabular depth-to-width ratio.

RESULTS

In total, 451 patients were included in this study. Twenty two percent of the patients had hip dysplasia, based on a LCEA of <25° and 42.6% of patients had hip dysplasia, based on a Tönnis angle of > 10°. The mean LCEA and Tönnis angle were 31.47 ± 9.64 and 9.82 ± 6.79°, respectively.

CONCLUSION

Hip dysplasia is common in patients undergoing THA under the age of 50 years with over 40% having dysplasia according to the Tönnis angle. Classification of primary and secondary osteoarthritis in the joint registries will benefit our knowledge on the prevalence of DDH in the adult population.

Enhancing acetabular reaming accuracy: optimal techniques and a novel reamer design

INTRODUCTION

Successful press-fit implantation relies on an accurately reamed bone cavity. Inaccurate reaming can lead to a suboptimal press-fit risking fracture and cup deformation or excessive micromotion and loosening. Several factors may impact reaming accuracy including the reamer design, the surgeon's technique and the bone quality. The aim of this study is to investigate the accuracy of reaming techniques and the accuracy of a novel reamer design.

METHODS

Eighty composite bone models, half high density and half low density, were reamed with either a conventional or an additively manufactured reamer with a novel design employing either a straight or 'whirlwind' reaming technique. Reamed cavities were scanned using a 3D laser scanner and the median difference between achieved and expected diameters compared.

RESULTS

The novel reamer design was more accurate than the unused conventional reamer, using both whirlwind (0.1 mm (IQR 0-0.2) vs. 0.3 mm (IQR 0.3-0.4); p < 0.001) and straight techniques (0.3 mm (IQR 0.1-1.0) vs. 1.2 mm (IQR 1-1.6); p = 0.001). Whirlwind reaming was more accurate than straight reaming using both conventional (0.3 mm (IQR 0.3-0.4) vs. 1.2 mm (IQR 1-1.6); p < 0.0001) and single use reamers (0.1 mm (IQR 0-0.2) vs. 0.3 mm (IQR 0.1-1.0); p = 0.007). Reaming errors were higher in low-density bone compared to high-density bone, for both reamer types and reaming techniques tested (0.6 mm (IQR 0.3-1.5) vs. 0.3 mm (IQR 0.1-0.8); p = 0.005).

CONCLUSION

We present a novel reamer design that demonstrates superior accuracy to conventional reamers in achieving the desired reaming diameter. Improved reaming accuracy was also demonstrated using both devices and in both bone models, using a 'whirlwind' technique. We recommend the use of this novel reamer design employing a 'whirlwind' technique to optimize reaming accuracy. Particular attention should be paid toward patients with lower bone quality which may be more susceptible to higher inaccuracies.

Covering of wound infection in hip arthroplasty with local cutaneous flaps

Total hip arthroplasty is a very common procedure to treat osteoarthritis. One of the complication is the infection which occurs in about 1% of the cases. The manifestation of infection can be poor wound healing with dehiscence and exposition of bone or prosthetic components. Hip arthroplasty infections are difficult to treat. It required an associated multidisciplinary approach with infectiology, orthopedic and plastic surgeries. The study included five patients with hip wound dehiscence after total hip arthroplasty. Coverage after orthopedic surgery was provided by local cutaneous flap. These cutaneous flaps were either a deep inferior epigastric perforator flap (DIEP) or a transposition flap. The orthopedic and the plastic treatment were done at the same time. Two deep inferior epigastric flaps were performed for patients with a deep defect with bone or prosthesis exposure. Four transposition flaps were done in three patients with wound dehiscence but without direct contact with the prosthesis. Three transposition flaps were done from the abdominal wall and one from the posterior thigh. The mean follow up was 18 months, ranging from 10 to 24months. After healing, there was no recurrence of the infection. In all cases, the coverage was obtained. The prosthesis was salvage and the gait was possible. Cutaneous flaps are easy and safe to cover the hip. They are reliable flaps even in patients with multiple co-morbidities. They do not cause sequelae on the recipient site. This study is the first about cutaneous flap for covering hip defects in hip arthroplasty infections.

A Bibliometric Analysis of the Top 100 Most Influential Studies on Robotic Arthroplasty

Background

The use of robotics in arthroplasty surgery has increased substantially in recent years. The purpose of this study was to objectively identify the 100 most influential studies in the robotic arthroplasty literature and to conduct a bibliometric analysis of these studies to describe their key characteristics.

Methods

The Clarivate Analytics Web of Knowledge database was used to gather data and metrics for robotic arthroplasty research using Boolean queries. The search list was sorted in descending order by the number of citations, and articles were included or excluded based on clinical relevance to robotic arthroplasty.

Results

The top 100 studies were cited a total of 5770 times from 1997 to 2021, with rapid growth in both citation generation and the number of articles published occurring in the past 5 years. The top 100 robotic arthroplasty articles originated from 12 countries, with the United States being responsible for almost half of the top 100. The most common study types were comparative studies (36) followed by case series (20), and the most common levels of evidence were III (23) and IV (33).

Conclusions

Research on robotic arthroplasty is rapidly growing and originates from a wide variety of countries, academic institutions, and with significant industry influence. This article serves as a reference to direct orthopaedic practitioners to the 100 most influential studies in robotic arthroplasty. We hope that these 100 studies and the analysis we provide aid healthcare professionals in efficiently assessing consensus, trends, and needs within the field.

Comparison of mortality rate and septic and aseptic revisions in total hip arthroplasties for osteoarthritis and femoral neck fracture: an analysis of the German Arthroplasty Registry

BACKGROUND

Indications for total hip arthroplasties (THA) differ from primary osteoarthritis (OA), which allows elective surgery through femoral neck fractures (FNF), which require timely surgical care. The aim of this investigation was to compare mortality and revisions in THA for primary OA and FNF.

METHODS

Data collection for this study was performed using the German Arthroplasty Registry (EPRD) with analysis THA for the treatment of FNF and OA. Cases were matched 1:1 according to age, sex, body mass index (BMI), cementation, and the Elixhauser score using Mahalanobis distance matching.

RESULTS

Overall 43,436 cases of THA for the treatment of OA and FNF were analyzed in this study. Mortality was significantly increased in FNF, with 12.6% after 1 year and 36.5% after 5 years compared with 3.0% and 18.7% in OA, respectively (p < 0.0001). The proportion for septic and aseptic revisions was significantly increased in FNF (p < 0.0001). Main causes for an aseptic failure were mechanical complications (OA: 1.1%; FNF: 2.4%; p < 0.0001) and periprosthetic fractures (OA: 0.2%; FNF: 0.4%; p = 0.021). As influencing factors for male patients with septic failure (p < 0.002), increased BMI and Elixhauser comorbidity score and diagnosis of fracture (all p < 0.0001) were identified. For aseptic revision surgeries, BMI, Elixhauser score, and FNF were influencing factors (p < 0.0001), while all cemented and hybrid cemented THA were associated with a risk reduction for aseptic failure within 90 days after surgery (p < 0.0001).

CONCLUSION

In femoral neck fractures treated with THA, a significant higher mortality, as well as septic and aseptic failure rate, was demonstrated compared with prosthesis for the therapy of osteoarthritis. Increased Elixhauser comorbidity score and BMI are the main influencing factors for development of septic or aseptic failure and can represent a potential approach for prevention measures.

LEVEL OF EVIDENCE

Level III, Prognostic.

How do patients sleep after orthopaedic surgery? Changes in objective sleep parameters and pain in hospitalized patients undergoing hip and knee arthroplasty

PURPOSE

The aim of this observational cohort study was to assess actigraphy-based sleep characteristics and pain scores in patients undergoing knee or hip joint replacement and hospitalized for ten days after surgery.

METHODS

N=20 subjects (mean age: 64.0±10.39 years old) wore the Actiwatch 2 actigraph (Philips Respironics, USA) to record sleep parameters for 11 consecutive days. Subjective scores of pain, by a visual analog scale (VAS), were constantly monitored and the following evaluation time points were considered for the analysis: pre-surgery (PRE), the first (POST1), the fourth (POST4), and the tenth day (POST10) after surgery.

RESULTS

Sleep quantity and timing parameters did not differ from PRE to POST10, during the hospitalization whereas sleep efficiency and immobility time significantly decreased at POST1 compared to PRE by 10.8% (p=0.003; ES: 0.9, moderate) and 9.4% (p=0.005; ES: 0.86, moderate) respectively, and sleep latency increased by 18.7 min (+320%) at POST1 compared to PRE (p=0.046; ES: 0.70, moderate). Overall, all sleep quality parameters showed a trend of constant improvement from POST1 to POST10. VAS scores were higher in the first day post-surgery (4.58 ± 2.46; p=0.0011 and ES: 1.40, large) compared to POST10 (1.68 ± 1.58). During the time, mean VAS showed significant negative correlations with mean sleep efficiency (r = -0.71; p=0.021).

CONCLUSION

Sleep quantity and timing parameters were stable during the entire hospitalization whereas sleep quality parameters significantly worsened the first night after surgery compared to the pre-surgery night. High scores of pain were associated with lower overall sleep quality.

In France, distance from hospital and health care structure impact on outcome after arthroplasty of the hip for proximal fractures of the femur

BACKGROUND

Hip arthroplasty is a frequently performed procedure in orthopedic surgery, carried out in almost all health structures for two main issues: fracture and coxarthrosis. Even if volume-outcome relationship appeared associated in many surgeries recently, data provided are not sufficient to set surgical thresholds neither than closing down low-volumes centers.

QUESTION

With this study, we wanted to identify surgical, health care-related and territorial factors influencing patient' mortality and readmission after a HA for a femoral fracture in 2018 in France.

PATIENTS AND METHODS

Data were anonymously collected from French nationwide administrative databases. All patients who underwent a hip arthroplasty for a femoral fracture through 2018 were included. Patient outcome was 90-day mortality and 90-day readmission rate after surgery.

RESULTS

Of the 36,252 patients that underwent a HA for fracture in France in 2018, 0.7% died within 90-day year and 1.2% were readmitted. Male and Charlson comorbidity index were associated with a higher 90-day mortality and readmission rate in multivariate analysis. High volume was associated with a lower mortality rate. Neither time of travel nor distance upon health facility were associated with mortality nor with readmission rate in the analysis.

CONCLUSION

Even if volume appears to be associated with lower mortality rate even for longer distance and time of travel, the persistence of exogenous factors not documented in the French databases suggests that regionalization of hip arthroplasty should be organized with caution.

CLINICAL RELEVANCE

As volume-outcome relationship must be interpreted with caution, policy makers should not regionalize such surgery without further investigation.

A randomized controlled trial of iliopsoas plane block vs. femoral nerve block for hip arthroplasty

BACKGROUND

Iliopsoas plane block (IPB) is a novel analgesic technique for hip surgery that retains quadriceps strength. However, evidence from randomized controlled trial is remains unavailable. We hypothesized that IPB, as a motor-sparing analgesic technique, could match the femoral nerve block (FNB) in pain management and morphine consumption, providing an advantage for earlier functional training in patients underwent hip arthroplasty.

METHODS

We recruited ninety patients with femoral neck fracture, femoral head necrosis or hip osteoarthritis who were scheduled for unilateral primary hip arthroplasty were recruited and received either IPB or FNB. Primary outcome was the pain score during hip flexion at 4 h after surgery. Secondary outcomes included quadriceps strength and pain scores upon arrival at post anesthesia care unit (PACU) and at 2, 4, 6, 24, 48 h after surgery, the first time out of bed, total opioids consumption, patient satisfaction, and complications.

RESULTS

There was no significant difference in terms of pain score during hip flexion at 4 h after surgery between the IPB group and FNB group. The quadriceps strength of patients receiving IPB was superior to those receiving FNB upon arrival at PACU and at 2, 4, 6 and 24 h after surgery. The IPB group showed a shorter first time out of bed compared to the FNB group. However, there were no significant differences in terms of pain scores within 48 h after surgery, total opioids consumption, patient satisfaction and complications between the two groups.

CONCLUSION

IPB was not superior to FNB in terms of postoperative analgesia for hip arthroplasty. However, IPB could serve as an effective motor-sparing analgesic technique for hip arthroplasty, which would facilitate early recovery and rehabilitation. This makes IPB worth considering as an alternative to FNB.

TRIAL REGISTRATION

The trial was registered prior to patient enrollment at the Chinese Clinical Trial Registry (ChiCTR2200055493; registration date: January 10, 2022; enrollment date: January 18, 2022; https://www.chictr.org.cn/searchprojEN.html ).