The Financial Burden of Patient Comorbidities on Total Hip Arthroplasties-A Matched Cohort Analysis of High Comorbidity Burden and Non-High Comorbidity Burden Patients

BACKGROUND

The impact of increased patient comorbidities on the cost-effectiveness of total hip arthroplasty (THAs) is lacking. This study aimed to compare revenue, costs, and short-term (90 days) surgical outcomes between patients who have and do not have a high comorbidity burden (HCB).

METHODS

We retrospectively reviewed 14,949 patients who underwent an elective, unilateral THA between 2012 and 2021. Patients were stratified into HCB (Charlson Comorbidity Index ≥ 5 and American Society of Anesthesiology scores of 3 or 4) and non-HCB groups, and were further 1:1 propensity matched based on baseline characteristics. Perioperative data, revenue, costs, and contribution margins (CMs) of the inpatient episode were compared between groups. Also, 90-day readmissions and revisions were compared between groups. Of the 11,717 patients who had available financial data (n = 1,017 HCB, n = 10,700 non-HCB), 1,914 patients were included in the final matched analyses (957 per group).

RESULTS

Total (P < .001) and direct (P < .001) costs were significantly higher for HCB patients. Comparable revenue between cohorts (P = .083) resulted in a significantly decreased CM in the HCB patient group (P < .001). The HCB patients were less likely to be discharged home (P < .001) and had significantly higher 90-day readmission rates (P = .049).

CONCLUSIONS

Increased THA costs for HCB patients were not matched by increased revenue, resulting in decreased CM. Higher rates of nonhome discharge and readmissions in the HCB population add to the additional financial burden. Adjustments to the current reimbursement models should better account for the increased financial burden of HCB patients undergoing THA and ensure access to care for all patient populations.

LEVEL OF EVIDENCE

III.

Acute Periprosthetic Hip Fractures With Short, Uncemented Femoral Stems

BACKGROUND

Uncemented femoral stems in hip arthroplasty have shown excellent long-term results, and several systematic studies indicate satisfactory performance of short stems. However, biomechanical and finite element analysis studies have suggested that shorter stems allow greater micromotion, producing greater strain at the implant-bone interface, which potentially increases the risk for periprosthetic fracture (PPF). We sought to assess this risk within our unit.

METHODS

Our institution's arthroplasty database was searched for all primary total hip arthroplasties using short femoral stems performed between July 14, 2009 and August 29, 2022. The overall PPF rate and the PPF rate for individual femoral stems were established. Preoperative X-rays for each case were analyzed to characterize individual proximal femoral geometry. A data analysis was performed to identify risk factors for PPF.

RESULTS

For the time period assessed, 3,192 short femoral stems were implanted. This included 1,561 of stem A and 1,631 of stem B. Women constituted 55.37% of the cohort. The average patient age was 66 years (range, 22 to 95). The PPF rate was 0.6%, with 19 PPFs identified at a follow-up of 3 months. There was a significantly higher fracture rate in stem A (0.96%) compared to stem B (0.25%) (P ≤ .01). Proximal femoral geometry, age, and sex were not determined to be risk factors for PPF in our cohort. Individual surgeons and surgical approaches appeared to confer no increased risk. There was no significant difference in average stem length, but multivariate analysis identified stem type and stem length as an independent risk factor for PPF.

CONCLUSIONS

Our study identified individual stem and stem length as independent risk factors for PPF within our cohort. PPF is a multifactorial issue, and consensus on emerging risk factors such as implant design will hopefully inform decisions that can provide further risk reduction for individual patients.

Total hip arthroplasty in adolescents: a systematic review and meta-analysis

PURPOSE

Total hip arthroplasty (THA) has demonstrated excellent results in elderly patients, however, the indications, outcomes, and long-term results in adolescent patients are less understood. This study aims to assess the outcomes of THA in patients under 21, providing insights for clinical decision-making in this exceptional population.

METHODS

A systematic review in PubMed, Ovid MEDLINE, and Embase database was performed. We included studies reporting clinical, radiological, and functional outcomes of THA in patients younger than 21 years, for any cause, with a with a minimum follow-up of one year. The ten year survivorship estimate was pooled using a meta-analysis methodology and each study was weighted according to its standard error, calculated from published confidence intervals.

RESULTS

We included 25 studies involving 1166 hips. Median age was 17 years old, 60% were females, and the average follow-up was 8.1 years. Juvenile inflammatory arthritis was the main indication for total hip arthroplasty (THA). The all-cause revision rate was 14.4% and aseptic loosening was the most common cause. Only eight studies reported ten year survival rates and form the pooled analysis an 84.91% survival rate (95% CI 70.56 - 99.27) was obtained. An average score of 88.08 in the Harris Hip Score (HHS) was observed. We found a 3.43% complication rate.

CONCLUSIONS

Hip arthroplasty is an acceptable option for adolescents with end-stage arthritis. However, the altered hip anatomy, the elevated revision rate, and the long-term implant survival must be considered before performing a THA in adolescent patients.

Unseen Threefold Mortality After the First Ten Days in Hemodialysis Patients Following Joint Arthroplasty: A Nationwide Retrospective Cohort Study of 1,287 Arthroplasty Patients on Hemodialysis

BACKGROUND

The study addresses the growing number of hemodialysis (HD) patients undergoing joint arthroplasty, who are at higher risk of complications and mortality. Previous research has often overlooked deaths after discharge. This study aimed to examine early outcomes in a large nationwide cohort of patients who underwent arthroplasty for elective and fracture-related reasons.

METHODS

Between 2016 and 2022, a study was conducted using the e-Nabız database of the Türkiye Ministry of Health, focusing on patients aged 18 years and above who underwent elective or fracture-related arthroplasty. This study included 1,287 patients reliant on dialysis who underwent total hip arthroplasty, total knee arthroplasty, or hemiarthroplasty (HA), with 7.7% of them receiving dialysis for the first time. Propensity score matching was used to create an equally sized group of non-dialysis-dependent patients, ensuring demographic balance in terms of age, sex, a comorbidity index, and surgery type. The primary objective was to compare mortality rates 10, 30, and 90 days after arthroplasty.

RESULTS

The first-time dialysis patients who underwent HA had significantly higher 30- and 90-day mortality rates compared to the chronic dialysis group (P = .040 and P < .001, respectively). Also, the HD patients consistently exhibited higher 90-day mortality rates across all surgery types. With total knee arthroplasty, HD patients had a mortality rate of 8.7%, in stark contrast to 0% among non-HD patients (P < .001). Similarly, with total hip arthroplasty, HD patients had a 12% mortality rate, while non-HD patients had a markedly lower rate of 2.7% (P = .008). In the case of HA, HD patients had a significantly elevated 90-day mortality rate of 31.9%, in contrast to 17.1% among non-HD patients (P < .001).

CONCLUSIONS

Joint arthroplasty has higher rates of mortality and complications among HD patients. Surgical decisions must be based on patients' overall health, necessitating collaboration among specialists. These patients should be closely monitored.

Femoral Head Penetration Rates and Oxidation of Highly Cross-Linked Polyethylene Hip Liners Implanted More Than 10 Years

BACKGROUND

Highly cross-linked polyethylene (HXLPE) was introduced to improve wear in total hip arthroplasty, with manufacturers implementing different thermal treatments to reduce oxidation. It is important to understand how long-term time in vivo affects the wear of these materials. The purpose of this study was to investigate the wear and oxidative performance of first-generation HXLPE hip inserts implanted for greater than 10 years and compare annealed and remelted HXLPE formulations.

METHODS

There were 49 total hip arthroplasty liners retrieved during routine revision surgery as part of an institutional review board-approved implant retrieval program. Penetration rates for the liners were calculated as the difference between the thickness of the unloaded and loaded regions divided by implantation time. Oxidation indices for the rim, locking mechanism, articulating surface, and backside regions were measured using Fourier-transform infrared spectroscopy according to American Society for Testing and Materials 2102. Mann-Whitney U tests were used to determine the statistical difference between annealed and remelted components.

RESULTS

The cohort had an average implantation time of 13.1 ± 2.6 years for annealed and 12.1 ± 1.7 years for remelted components. The components were revised most often for polyethylene wear, instability, and loosening. The penetration rate averaged 0.0177 ± 0.014 mm/year for annealed components and 0.015 ± 0.022 mm/year for remelted components. Penetration rates did not differ between the remelted and annealed cohorts (P = .28). Oxidation indices were found to be significantly higher in the annealed cohort for all regions of interest (P < .001).

CONCLUSIONS

Oxidation was found to be higher in the annealed HXLPE; however, this does not seem to be associated with greater wear as we found the average penetration rates for the cohorts were low, and the penetration rates were similar between the annealed and remelted cohorts.

Efficacy of Commercially Available Irrigation Solutions on Removal of Staphylococcus Aureus and Biofilm From Porous Titanium Implants: An In Vitro Study

BACKGROUND

Periprosthetic joint infection remains a major problem. The bactericidal efficacy of commercial irrigation solutions for the treatment of infection is not well established in the presence of porous titanium (Ti) implants. This study compared the in vitro efficacy of five irrigation solutions on infected three-dimensional-printed porous Ti discs.

METHODS

Titanium discs (2 × 4 mm, 400, 700, and 1,000 μm) were infected with S. aureus (1 × 106 colony-forming unit/mL) and incubated for 3 hours or 3 days to create acute or chronic infection with biofilm. Discs were irrigated with saline, antibiotic, or antiseptic solutions, then repeatedly sonicated. Sonicates were cultured for bacterial quantification. Statistical analyses were performed using one-way analysis of variance (ANOVA), followed by Tukey-Kramer post hoc testing (P < .05 significance). Biofilms were visualized by scanning electron microscopy.

RESULTS

Saline irrigation was ineffective in both groups. In acute infections with 400 μm pores, differences were found with saline versus solution #3 (P = .015) and #4 (P = .015). Solution #4 had the lowest bacterial counts for all pore sizes. For biofilm, irrigation with saline, solutions #1, #2, and #3 inadequately cleared bacteria in all pore sizes. Lower remaining concentrations were observed in #4 with 400μm pores compared to saline (P = .06) and #2 (P = .039). The scanning electron microscopy showed a reduction of biofilm in samples washed with #4.

CONCLUSIONS

Irrigation of infected porous Ti discs with saline, solutions #1 and #2 failed to reduce the bacterial load. The 400 μm discs consistently had more bacteria despite irrigation, highlighting the difficulty of removing bacteria from small pores. Solutions #3 and #4 reduced bacteria acutely, but only #4 demonstrated efficacy in clearing biofilm compared to saline. These results should be considered when treating periprosthetic joint infection in the presence of porous components and the potential presence of biofilm.

A Consecutive Series of Vancouver B2 Periprosthetic Femur Fractures Treated With Contemporary Monoblock Versus Modular Revision Stems: Clinical and Radiographic Outcomes

BACKGROUND

Tapered fluted titanium (TFT) stems are the implant design of choice for managing Vancouver B2 periprosthetic femur fractures (PFFs), producing reliable results over the past few decades. The aim of this study was to compare the radiographic and clinical outcomes of Vancouver B2 PFFs treated with contemporary monoblock versus modular TFTs.

METHODS

A consecutive series of 113 patients (72 women, 64%, mean age 70 years [range, 26 to 96]) who had a B2 PFF were treated with either a monoblock (n = 42) or modular (n = 71) TFT stem between 2008 and 2021. The mean body mass index was 30 ± 7. The mean follow-up was 2.9 years. A radiographic review was performed to assess leg length and offset restoration, endosteal cortical contact length, and stem subsidence. Kaplan-Meier analyses were used to determine survivorship without revision, reoperation, or dislocation.

RESULTS

There was no difference in the restoration of leg length (0.3 ± 8.0 mm) or offset (2.8 ± 8.2 mm) between the monoblock and modular cohorts (P > .05). Mean endosteal cortical contact length (47.2 ± 26.6 versus 46.7 ± 2 6.4 mm, P = .89) and stem subsidence (2.7 ± 3.5 versus 2.4 ± 3.2 mm, P = .66) did not differ. No difference in patient-reported outcome measures (Hip Disability and Osteoarthritis Outcome Score-Joint Replacement; Veterans RAND 12 Item Health Survey Physical and Mental; visual analog score; and Lower Extremity Activity Scale) between the groups was observed. Survivorship at 2 years free from reoperation, revision, and dislocation was 90.4, 90.3, and 97.6%, respectively, for the monoblock cohort; and 84.0, 86.9, and 90.0%, respectively, for the modular cohort.

CONCLUSIONS

No significant differences in radiographic or clinical outcomes were observed between patients treated with monoblock or modular TFTs in this large series of B2 PFFs.

Is American Joint Replacement Registry Data Consistent With International Survivorship in Hip and Knee Arthroplasty? A Comparative Analysis

BACKGROUND

In collaboration with the Orthopedic Data Evaluation Panel (ODEP), the American Joint Replacement Registry (AJRR) investigated the consistency of hip and knee arthroplasty survivorship results compared to the UK National Joint Registry (NJR).

METHODS

A total of three primary knee devices and three primary hip devices were selected by AJRR and ODEP with known variation in performance. Implant manufacturers independently produced Kaplan Meier survivorship based on NJR data and submitted to ODEP for comparison. The AJRR mirrored the methodology, and results from both sources were stratified into three cohorts (all-age, < 65, and ≥ 65 years).

RESULTS

There were 42,671 AJRR and 60,439 NJR primary knee cases and 70,169 AJRR and 422,657 NJR primary total hip arthroplasty cases. For TKA, performance between the AJRR and NJR were consistent, showing similar trends for comparatively high and low performing devices. Both PS and CR devices showed statistical agreement in survivorship for all 3 cohorts. Unicompartmental comparison also showed statistical agreement for the Medicare cohort. The all-age and < 65-year-old cohorts showed similar trends and reached statistical agreement through 7 and 6 years. For total hip arthroplasty, performance between the AJRR and NJR were consistent, showing similar trends for comparatively high and low performing devices; 0.18% average difference in survivorship at final follow-up (8 years). One femoral device did not reach statistical agreement but showed only 0.61% difference in survivorship. The remaining acetabular and femoral devices reached statistical agreement in all-ages and through 7 and 8 years in the ≥ 65-year-old cohort.

CONCLUSIONS

AJRR and NJR performance trends and survivorship were similar across hip and knee arthroplasty with greatest consistency in the all-age and ≥ 65 cohorts. This focused comparison of survivorship showed encouraging results for reliability of patient outcomes in AJRR compared to the world's largest joint arthroplasty registry which has strong implications for global improvement in patient safety.

Contribution of the Medial Iliofemoral Ligament to Hip Stability After Total Hip Arthroplasty Through the Direct Anterior Approach

BACKGROUND

Dislocation after total hip arthroplasty (THA) is a primary reason for THA revision. During THA through the direct anterior approach (DAA), the iliofemoral ligament, which provides the main resistance to external rotation (ER) of the hip, is commonly partially transected. We asked: (1) what is the contribution of the medial iliofemoral ligament to resisting ER after DAA THA? and (2) how much resistance to ER can be restored by repairing the ligament?

METHODS

A fellowship-trained surgeon performed DAA THA on 9 cadaveric specimens. The specimens were computed tomography scanned before and after implantation. Prior to testing, the ER range of motion of each specimen to impingement in neutral and 10° of extension was computationally predicted. Each specimen was tested on a 6-degrees-of-freedom robotic manipulator. The pelvis was placed in neutral and 10° of extension. The femur was externally rotated until it reached the specimen's impingement target. Total ER torque was recorded with the medial iliofemoral ligament intact, after transecting the ligament, and after repair. Torque at extremes of motion was calculated for each condition. To isolate the contribution of the native ligament, the torque for the transected state was subtracted from both the native and repaired conditions.

RESULTS

The medial iliofemoral ligament contributed an average of 68% (range, 34 to 87) of the total torque at the extreme of motion in neutral and 80% (58 to 97) in 10⁰ of extension. The repaired ligament contributed 17% (1 to 54) of the total torque at the extreme of motion in neutral and 14% (5 to 38) in 10⁰ of extension, restoring on average 18 to 25% of the native resistance against ER.

CONCLUSIONS

The medial iliofemoral ligament was an important contributor to the hip torque at the extreme of motion during ER. Repairing the ligament restored a fraction of its ability to generate torque to resist ER.

Ceramic-on-Ceramic Total Hip Arthroplasty Using a Double Tapered, Proximally Coated Stem: 15 to 24-year Clinical and Radiologic Follow-Up

BACKGROUND

Total hip arthroplasty implant choice profoundly affects survivorship, complications, and failure modes. This study evaluates the long-term (average 18 year) outcomes of ceramic-on-ceramic hip arthroplasty using uncemented shells and stems. Despite an impressive 20-year cumulative percent revision of 5.9%, the hydroxyapatite proximally coated femoral components evaluated in this study have seen declining use since 2003.

METHODS

A review of 349 consecutive total hip arthroplasties from 1999 to 2007 was matched to 272 cases with registry data. A survivorship analysis included 274 hips (Group A) after excluding patients lost to follow-up and navigated cases. Group B comprised 135 patients who had complete datasets spanning a minimum of 15 years.

RESULTS

Kaplan-Meier analysis identified a 95.6% survivorship plateau at 16 to 24 years, with no significant impact from age, sex, component size, or original pathology. In Group B, EuroQol-5 Dimensions-5 Levels (EQ5D5L) scores indicated favorable outcomes in mobility, self-care, activities, pain/discomfort, and anxiety/depression, with an EQ5D visual analog score mean of 79.24. Functional scores, including the Harris Hip Score, Oxford Hip Score, and Forgotten Joint Score, showed positive outcomes. Radiologic assessments revealed no osteolysis or loose components, with a mean Engh score of 21.69. Dorr classification identified bone quality variations. Better Engh scores corresponded to higher levels of patient satisfaction. Age at surgery was correlated with better functional scores, while sex influenced various outcomes.

CONCLUSIONS

This comprehensive study, spanning an average of 18.23 years, combined multiple patient-reported outcome measures with extensive clinical and radiologic follow-up. It reported a notably high survivorship rate for this implant combination but highlighted the declining use of the hydroxyapatite proximally coated femoral stem used in this study, potentially facing withdrawal risks in Australia.

LEVEL OF EVIDENCE

Therapeutic Level IV.

The Association of Dental Caries or Dental Implant Placement Within One Year of Primary Total Hip Arthroplasty on Medical and Implant Complications

BACKGROUND

Total hip arthroplasty (THA) adverse events among patients who have dental diagnoses remain unclear. We sought to determine if dental caries or dental implant placements increased (1) 90-day medical complications, (2) 90-day readmissions, and (3) 2-year implant-related complications, including periprosthetic joint infections (PJIs) after THA.

METHODS

A nationwide database for primary THAs from 2010 to 2021 was queried to compare 3 patient cohorts. Patients who had a history of dental implants or caries within 12 months prior to THA (n = 1,179) or 12 months after THA (n = 1,218) were case-matched to patients who did not have dental history (n = 6,090) by age and comorbidities. Outcomes included 90-day complications, 90-day readmissions, and 2-year implant-related complications. Logistic regression models computed the odds ratios (ORs) of complications and readmissions. P values less than .006 were significant.

RESULTS

Patients who had dental caries or implant placement 12 months before or after THA experienced 1.6-fold greater odds of 90-day medical complications compared to case-matched patients. Readmissions within 90 days increased for patients who had a dental history before (11.7% versus 8.3%; OR: 1.49, P < .0001) and after (14.2% versus 8.3%; OR: 1.84, P < .0001) THA compared to case-matched patients. A dental caries diagnosis or dental implant placement within 12 months following THA increased 2-year implant complications compared to case-matched patients (15.2% versus 9.3%; OR: 1.69, P < .0001), including PJIs (5.3% versus 2.8%; OR: 1.98, P < .0001), dislocations (4.4% versus 2.7%; OR: 1.63, P = .002), and THA revisions (3.9% versus 2.5%; OR: 1.61, P = .005).

CONCLUSIONS

Dental diagnoses within 12 months of THA are associated with increased medical complications. Dental diagnoses occurring 12 months after THA are associated with greater implant-related complications, including PJIs. Delaying invasive dental procedures for 12 months after THA may be advisable.

Prevalence of total joint arthroplasty in the adult spine deformity population

PURPOSE

The spine, hip, and knee are anatomically and biomechanically connected. Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are commonly employed to treat degenerative changes in the hip and knee, while fusion is used for spine degeneration. Spine deformity correction results in changes in sagittal alignment and pelvic parameters, and patients with stiff spines have higher rates of THA dislocation and revision due to instability. The goal of this study was to determine the prevalence of total joint arthroplasty (TJA) in adult spinal deformity (ASD) patients at our institution.

METHODS

Following Institutional Review Board approval, we retrospectively reviewed a list of cases performed by the senior author from 4/2017 to 5/2021. Patients > 18 years old undergoing preoperative evaluation for symptomatic lumbar degeneration or ASD were included. Patients < 18 years old, those diagnosed with adolescent idiopathic scoliosis, and non-fusion cases were excluded. Perioperative full-length standing EOS images were examined for the presence or absence of THA, TKA, or both. Demographic data was collected from patient electronic medical records, and statistical analyses were completed.

RESULTS

572 consecutive cases were reviewed, and 322 were excluded. 250 cases (97M:153F) were included in the final analysis, with a mean age of 61.8 ± 11.2 years. A total of 74 patients had a TJA (29.4%). THA was present in 41 patients (16.4%), and TKA was present in 49 patients (19.6%). Males had a higher prevalence of TJA, THA, and TKA (29.9%, 16.5%, and 21.6%) than females (29.4%, 16.3%, and 18.3%).

CONCLUSIONS

This study revealed a high prevalence TJA rate of 29.4% in ASD at our institution. This rate surpasses the prevalence rate reported among the general population in previous studies. High prevalence of patients with ASD and TJA may merit special surgical consideration.

The Frank Stinchfield Award: Assembly and Dissociation Forces Differ Between Commonly Used Dual Mobility Implants: A Biomechanical Study

BACKGROUND

Intraprosthetic dissociation (IPD) is a complication unique to dual mobility (DM) implants where the outer polyethylene head dissociates from the inner femoral head. Increasing reports of IPD at the time of closed reduction of large head DM dislocations prompted this biomechanical study evaluating the assembly and dissociation forces of DM heads.

METHODS

We tested 17 polyethylene DM heads from 5 vendors. Of the heads, 12 were highly cross-linked polyethylene (4 vendors) and 5 were infused with vitamin E (2 vendors). Heads were between 46 and 47 mm in diameter, accepting a 28 mm-inner ceramic head. Implants were assembled and disassembled using a servohydraulic machine that recorded the forces and torques applied during testing. Dissociation was tested via both axial pull-out and lever-out techniques, where lever-out simulated stem-on-acetabular component impingement.

RESULTS

The initial maximum assembly force was significantly different between all vendors (P < .01) and decreased for all implants with subsequent assembly. Vendor 4-E (Link with vitamin E) heads required the highest assembly force (1,831.9 ± 81.95 N), followed by Vendor 3 (Smith & Nephew), Vendor 5 (DePuy Synthes), Vendor 1-E (Zimmer Biomet with vitamin E), Vendor 2 (Stryker), and Vendor 1 (Zimmer Biomet Arcom). Vendor 4-E implants showed the greatest dissociation resistance in both pull-out (2,059.89 N, n = 1) and lever-out (38.95 ± 2.79 Nm) tests. Vendor 1-E implants with vitamin E required higher assembly force, dissociation force, and energy than Vendor 1 heads without vitamin E.

CONCLUSIONS

There were notable differences in DM assembly and dissociation forces between implants. Diminishing force was required for assembly with each additional trial across vendors. Vendor 4-E DM heads required the highest assembly and dissociation forces. Vitamin E appeared to increase the assembly and dissociation forces. Based on these results, DM polyethylene heads should not be reimplanted after dissociation, and there may be a role for establishing a minimum dissociation energy standard to minimize IPD risk.

Patient Experience and Satisfaction with Orthopedic Services at a Community (Rural) Setting Hospital-How Is It Different from Urban Setting

Patient experience and satisfaction are the keystones in evaluating the effectiveness of clinical care in musculoskeletal medicine. Although all orthopedic settings work on the same principles of providing safe and quality health care, community hospitals represent a unique environment. There may be key differences with regard to patient experience between these settings. Accessibility to care, choices of provider, personalized care, availability of and access to resources, cultural and social variances, and waiting times are a few of the many elements that may impact patient experience and satisfaction. This narrative review aims to explore the core differences in these settings and how they can reflect on patient experience and satisfaction.

Femoral Component Debonding Frequently Missed on Advanced Imaging Prior to Revision of a Recalled Total Knee Arthroplasty

BACKGROUND

Identification of femoral component debonding in the work-up of painful total knee arthroplasty (TKA) often poses a diagnostic challenge. The purpose of this study was to compare the sensitivity and specificity of radiographs, computed tomography (CT), and magnetic resonance imaging (MRI) for identifying femoral component loosening with debonding at the time of revision of a primary TKA with a recalled polyethylene insert.

METHODS

Using an institutional database, we identified all cases of revision TKA performed for this specific implant recall following a primary TKA between 2014 and 2022. Patients who had a preoperative radiograph, CT, and MRI were included (n = 77). Sensitivity, specificity, and positive and negative likelihood ratio (LR) for predicting loosening were compared among the imaging modalities, using the intraoperative evidence of implant loosening as the gold standard.

RESULTS

At the time of revision surgery, the femoral component was noted to have aseptic loosening with debonding in 46 of the 77 (60%) of the TKAs. There were no significant differences in demographics in the cohort with femoral debonding compared to those with well-fixed implants. The CT demonstrated a sensitivity of 28% and a specificity of 97%, while the MRI demonstrated a sensitivity of 37% and a specificity of 94% for detecting femoral loosening due to debonding. Both CT and MRI demonstrated poor negative LRs for femoral loosening (LR 0.7).

CONCLUSIONS

In this series of revision TKAs for a specific recalled component, neither CT nor MRI accurately diagnosed femoral component debonding. For patients who have this implant, it is imperative to interrogate the implant-cement interface intraoperatively and prepare for full revision surgery as well as marked bone loss secondary to osteolysis.

Two-Dimensional Versus Three-Dimensional Preoperative Planning in Total Hip Arthroplasty

BACKGROUND

Preoperative planning in total hip arthroplasty (THA) involves utilizing radiographs or advanced imaging modalities, including computerized tomography scans, for precise prediction of implant sizing and positioning. This study aimed to compare 3-dimensional (3D) versus 2-dimensional (2D) preoperative planning in primary THA with respect to key surgical metrics, including restoration of the horizontal and vertical center of rotation (COR), combined offset, and leg length.

METHODS

This study included 60 patients undergoing primary THA for symptomatic hip osteoarthritis (OA), randomly allocated to either robotic arm-assisted or conventional THA. Digital 2D templating and 3D planning using the robotic software were performed for all patients. All measurements to evaluate the accuracy of templating methods were conducted on the preoperative computerized tomography scanogram, using the contralateral hip as a reference. Sensitivity analyses explored differences between 2D and 3D planning in patients who had superolateral or medial OA patterns.

RESULTS

Compared to 2D templating, 3D templating was associated with less medialization of the horizontal COR (-1.2 versus -0.2 mm, P = .002) and more accurate restoration of the vertical COR (1.63 versus 0.3 mm, P < .001) with respect to the contralateral side. Furthermore, 3D templating was superior for planned restoration of leg length (+0.23 versus -0.74 mm, P = .019). Sensitivity analyses demonstrated that in patients who had medial OA, 3D planning resulted in less medialization of horizontal COR and less offset reduction. Conversely, in patients who had superolateral OA, there was less lateralization of horizontal COR and less offset increase using 3D planning. Additionally, 3D planning showed superior reproducibility for stem, acetabular cup sizes, and neck angle, while 2D planning often led to smaller stem and cup sizes.

CONCLUSIONS

Our findings indicated higher accuracy in the planned restoration of native joint mechanics using 3D planning. Additionally, this study highlights distinct variances between the 2 planning methods across different OA pattern subtypes, offering valuable insights for clinicians employing 2D planning.

An Extended Trochanteric Osteotomy Is Necessary for the Removal of Broken Modular Metaphyseal Engaging Femoral Stems

BACKGROUND

Modular metaphyseal engaging (MME) femoral components in total hip arthroplasty (THA) allow optimized femoral length, offset, and anteversion and are useful in patients with unusual proximal femoral anatomy. Fretting, corrosion, and stem fractures above the modular sleeve are complications associated with these implants. The purpose of this study was to identify failure mechanisms of retrieved MME femoral components at our institution, identify all broken stem cases, and evaluate how often an extended trochanteric osteotomy (ETO) was required for removal.

METHODS

All consecutively retrieved MME femoral components from September 2002 to May 2023 were reviewed. Patient demographics, procedure information, component specifications, indications for removal, and requirements for further revision surgery were reviewed. Descriptive statistics were calculated for variables of interest.

RESULTS

There were 131 retrieved MME components. The mean age at surgery was 59 years (range, 28 to 75), 49% were women, mean body mass index was 29.4 (range, 20.7 to 33.3), and mean American Society of Anesthesiologists score was 2.4 ± 0.5. There were 102 (78%) stems of 1 design (stem A), and 29 (22%) stems of a different design (stem B). Of 131 components, 10 (7.6%) failed secondary to stem fracture proximal to the modular sleeve. Four of 102 (4%) of stem A and 6 of 29 (21% of stem B) fractured. All broken stems required additional intervention for removal during revision THA, using an ETO (N = 9) or cortical window (N = 1) in which an intraoperative proximal femoral fracture occurred.

CONCLUSIONS

Broken MME stems present a challenge for orthopaedic surgeons during revision THA. When a stem fracture occurs above the ingrown sleeve, the distal splines may have osseous interdigitation into the clothespin. Thus, when revising a broken MME stem, an ETO should be performed, and the segment should be long enough to allow distal access.

Short-Term (90 Days) Clinical Outcomes Following the Day of Surgery Conversion of Inpatient to Same-Day Hip and Knee Arthroplasty

BACKGROUND

The incidence of total joint arthroplasty is increasing, with added emphasis on shifting care toward outpatient surgery. This has demonstrated improvements in costs and care; however, safety must be prioritized. Published assessment tools highlight candidates for outpatient surgery; however, they often do not define patients who have a worse prognosis. Limited healthcare resources occasionally force patients to convert to outpatient surgery or risk cancellation, creating a dilemma for both patients and surgeons. We evaluated the short-term (90-day) outcomes of patients converted from planned inpatient admission to same-day discharge on day of surgery outpatients and sought to identify any groups at risk, who may not be appropriate for this conversion.

METHODS

We identified all patients undergoing planned inpatient total hip or knee arthroplasty at a tertiary academic medical center over a 2-year period. We included patients discharged the day of surgery for analysis, excluding revision procedures and those performed for fracture care. A manual chart review identified demographic factors and primary outcome measures; including reoperation, readmission, and emergency room visits within a 90-day postoperative period.

RESULTS

We identified a total of 80 patients who converted from inpatient to outpatient surgery over a 2-year interval. Over the first 90 days postoperatively 4 (5%) patients were readmitted: 2 (2.5%) for medical complications and 2 (2.5%) for reoperation. There were 2 (2.5%) reoperations; one (1.25%) for manipulation under anesthesia, and one (1.25%) for periprosthetic joint infection. There were 5 (6.3%) wound complications; however, only one (1.25%) required surgical intervention. A total of 5 (6.3%) patients returned to an emergency department, leading to a single (1.25%) hospital readmission.

CONCLUSIONS

Hospital and healthcare resources are occasionally limited to the extent that patients must convert to outpatient surgery or risk cancellation. At our institution, the same-day conversion of planned inpatient hip and knee arthroplasty patients to outpatient surgery was safe and did not increase short-term clinical outcomes or complications.

Rapidly destructive hip osteoarthritis: a diagnosis not to miss

This review illustrates the imaging features of rapidly destructive hip osteoarthritis (RDHO) across different imaging modalities. RDHO is a rare joint disease of unknown aetiology resulting in rapid deterioration of the hip joints. Patients often present with severe hip pain and can progress to complete joint destruction in 6 months to 3 years causing disability. Since its clinical and imaging features often overlap with other conditions, the diagnosis is easily missed in daily practice. The purpose of this paper is to outline the characteristic imaging features of RDHO, aiming to enhance awareness of this disease entity and promote timely treatment for patients. Sequential radiographs are particularly important in demonstrating the rapid progression of radiographic findings and with the early recognition of characteristic features, diagnosis can be made to avoid treatment delay. Although CT scan is not necessary for diagnosis, it is useful in evaluating the extent of joint destruction and guiding surgical planning. MRI can provide additional information and rule out other pathologies with similar symptoms. Overall, radiographs, CT and MRI are common modalities used in the evaluation of RDHO.

Diffusion doping of analgesics into UHMWPE for prophylactic pain management

Pain management after total joint arthroplasty is often addressed by systemic delivery of opioids. Local delivery of non-opioid analgesic drugs directly in the joint space from the UHMWPE component of the prosthesis would be highly beneficial to increase the efficacy of the drugs, decreasing the overall side effects and the risk of opioid addiction. It has been shown that effective concentrations of local analgesics can be achieved by eluting from analgesic-blended UHMWPE; however, this approach is limited by the decrease in mechanical properties resulting from the extent of phase separation of the blended drugs from the polymeric matrix. Here we hypothesized that mechanical properties could be maintained by incorporating analgesics into solid form UHMWPE by diffusion as an alternative method. Lidocaine or bupivacaine were diffused in solid form UHMWPE with or without radiation crosslinking. The loaded drug content, the spatial distribution of the drugs and their chemical stability after doping were characterized by FTIR and NMR spectroscopy, respectively. Drug release kinetics, tensile mechanical properties and wear rates were assessed. The results showed that diffusion doping could be used as a promising method to obtain a therapeutic implant material without compromising its mechanical and structural integrity.

Complication rates are not higher after outpatient compared to inpatient fast-track total hip arthroplasty: a propensity-matched prospective comparative study

PURPOSE

Concerns remain with regards to safety of fast-track (FT) and especially outpatient procedures. The purpose of this study was to compare complication rates and clinical outcomes of propensity-matched patients who received FT total hip arthroplasty (THA) in outpatient versus inpatient settings. The hypothesis was that 90-day postoperative complication rates of outpatient FT THA would not be higher than after inpatient FT THA.

METHODS

This is a prospective study of consecutive patients who received FT THA at various rates of outpatient and inpatient surgery by 10 senior surgeons (10 centres). The decision between outpatient and inpatient surgery was made on a case-by-case basis depending on the surgeon and patient. All patients were followed until 90 days after surgery. Complications, readmissions and reoperations were collected, and their severity was assessed according to Clavien-Dindo. Patients completed Oxford Hip Score (OHS) at the latest follow-up.

RESULTS

Compared to inpatient FT THA, patients scheduled for outpatient FT THA had no significant differences in 90-day postoperative complication rates (10.7% vs. 12.9%, p = 0.129). There were no significant differences between the 2 groups in 90-day readmission rates and reoperation rates, in severity of postoperative complications, and in time of occurrence of postoperative complications.

CONCLUSIONS

There were no differences in rates of intraoperative complications, 90-day postoperative complications, readmissions, or reoperations between outpatient and inpatient FT THA. These findings may help hesitant surgeons to move towards outpatient THA pathways as there is no greater risk of early postoperative complications that could be more difficult to manage after discharge.

Nickel allergy does not correlate with function after total knee arthroplasty

PURPOSE

The purpose of this study is to determine if there is a relationship between clinical outcomes and nickel allergy by evaluating asymptomatic total knee arthroplasty (TKA) patients with well-functioning implants through quantitative metal allergy (MA) testing.

METHODS

A prospective case series was performed on 50 patients with well-functioning TKA of various implant types. Inclusion criteria included primary TKA with a minimum 12-month follow-up and Oxford knee score (OKS) ≥ 40. A commercially available Lymphocyte Transformation Test measured the amount of a hypersensitivity lymphocyte immune response after exposure to a particular antigen. MA results were stratified based on the stimulation index (SI). The Cochran-Mantel-Haenzel test was used to test the homogeneity of metal reactivities. The Wilcoxon-Mann-Whitney test was used to compare individual metal SI by gender and the association of OKS and metal SI was ascertained with the Spearman correlation.

RESULTS

Nickel, cobalt, and chromium do not have the same reactivity scores (p < 0.001), and only nickel showed reactive/highly reactive scores. Females were found to have 3.41 times the odds of males for higher Ni reactivity (p = 0.0295, odds ratio [OR], 95% confidence interval [CI] = 3.41 [1.13-10.3]) only. Clinically, there was no correlation between metal SI and OKS score by metal (Ni rho = -0.1779; Co rho = -0.0036; Cr rho = -0.1748).

CONCLUSION

This is the first study looking at MA in well-functioning TKA. There is no correlation between clinical results and nickel reactivity. Surgeons should exercise caution when revising a painful or poorly functioning TKA based solely on a 'positive' Nickel Allergy test and look for other possible reasons for failure.

LEVEL OF EVIDENCE

Level II.

Simultaneous Bilateral Total Hip Arthroplasty with Either the Direct Anterior or Posterior Approaches: A Propensity Score Match Study

INTRODUCTION

Bilateral hip osteoarthritis is evident in approximately 20% of patients who present to the clinic for evaluation of hip pain, and for those undergoing total hip arthroplasty (THA), 22% will end up needing a contralateral THA. The risk and benefits of simultaneous bilateral THA (SBTHA) versus staged bilateral THA procedures have been well studied, demonstrating equivalent safety profiles comparable to unilateral and SBTHA. However, the influence of the surgical approach on SBTHA on postoperative outcomes remains unclear. We sought to compare perioperative outcomes and complication rates between the direct anterior approach (DAA) and posterior approach (PA) in patients undergoing SBTHA.

METHODS

We performed a 1:1 propensity score match based on age, sex, and body mass index (BMI). A total of 252 patients were available after matching, 126 patients in the DAA group and 126 in the PA group. Perioperative outcomes as well as surgical complications at the latest follow-up were retrospectively collected for each group. The mean follow-up was 36.7 months (range, 12.5 to 74.4).

RESULTS

A SBTHA with DAA had significantly shorter surgical time (P < 0.001), anesthesia time (P < 0.001), and length of stay (P < 0.001), compared to the PA. A greater percentage of patients in the DAA group (91%) were discharged home compared to the PA group (57%) (P < 0.001). There were no differences in in-hospital complications (P = 0.617), 90-day complications (P = 0.605), or reoperation rates (P = 0.309) between surgical approaches.

CONCLUSION

A SBTHA, either through the DAA or PA, can be safely performed with low complication rates. The DAA in the setting of SBTHA provides shorter surgical times, a shorter length of stay, and a greater percentage of patients discharged home.

TRANSCULTURAL ADAPTATION AND VALIDATION OF THE 4-DOMAIN SPORTS PROM INTO ITALIAN

OBJECTIVES

This work aims to evaluate and validate the process of cross-cultural adaptation and validation of the 4-Domain Sports PROM (4-DSP) into Italian, assessing its understandability and reproducibility in all questionnaire domains for Italian-speaking patients.

METHODS

Cross-sectional study, level of evidence II. The questionnaire was self-administered by 100 patients (80 males and 20 females) who had undergone anterior cruciate ligament (ACL) reconstruction and had a one-year minimum follow-up. The mean age and standard deviation (SD) was 31.20 ± 12.65 years. According to their level of sports participation, 51% were recreational, 31% were regional, 12% were national, and 6% were international athletes. All patients filled in the 4-DSP questionnaire without direct supervision of their trainer/coach or researcher. All data were collected and processed anonymously. The translation and cultural adaptation of the 4-DSP involved six phases: (1) translation, (2) synthesis, (3) back-translation, (4) pre-test, (5) expert committee review, (6) final version approval by the author of the original version for publication.

RESULTS

The cross-cultural validation of the questionnaire 4-DSP into Italian presented a global Cronbach's ALPHA of 0.65, Conceptual equivalence to translation and relevance were 99.09% and 99.81%, respectively, and the percentage of agreement was 99.09%.

CONCLUSION

The cross-culturally validated version of the 4-DSP into Italian proved to be adequately understandable and reproducible in all questionnaire domains and can be safely and reliably used in Italian-speaking patients.

LEVEL OF EVIDENCE

Study level II.

Tibial post loading increases the risk of aseptic loosening of posterior-stabilized tibial prosthesis

Aseptic loosening is the primary cause of failure following posterior-stabilized total knee arthroplasty. It is unclear whether tibial post loading of posterior-stabilized prosthesis increases the risk of aseptic loosening of the tibial prosthesis. The purpose of this study is to investigate the biomechanical effects of tibial post loading on the tibial prosthesis fixation interface during level walking, squatting, stair descent, and standing up-sitting down activities. In this paper, finite element models with and without post were established to compare the effects of tibial post loading on the von Mises stress of the proximal tibia, shear stress of the cement, and the bone-prosthesis interface micromotion during four physiological activities. The tibial post loading had an insignificant influence on tibial biomechanics and bone-prosthesis interface micromotion during leveling walking activity. However, compared to the insert without post condition, tibial post loading significantly increased the maximum tibial von Mises stress, the maximum shear stress in the medial of cement, and the bone-prosthesis interface peak micromotion by 912.84%, 612.77%, and 921.09%, respectively, at the moment of the maximum flexion angle for the stair descent activity, and 637.92%, 351.43%, and 519.13%, respectively, at the moment of the maximum flexion angle for the standing up-sitting down activity. Tibial post loading increased the risk of postoperative aseptic loosening of tibial prosthesis in patients with posterior-stabilized total knee arthroplasty, and it was recommended that the post-cam contact mechanism of posterior-stabilized prosthesis should be optimized to reduce the biomechanical impact of tibial post loading on tibial prosthesis fixation.

Predictors and risk factors of pulmonary embolism after total hip arthroplasty: an NSQIP study

INTRODUCTION

Pulmonary embolism (PE) is a well-known contributor to morbidity after total hip arthroplasty (THA). Considerable efforts have been invested in reducing PE occurrence through pharmacological and perioperative interventions. Nonetheless, the effectiveness of these strategies in reducing the incidence and overall mortality associated with pulmonary embolism events remains a matter of debate. Therefore, identifying risky patients has been gaining importance.

METHODS

We utilised data from the National Surgical Quality Improvement Program (NSQIP) participant usage file (PUF) database spanning the years 2016 to 2021. All preoperative parameters were analysed with chi-square afterwards, meaningful ones were run with logistic regression test.

RESULTS

A study examined factors influencing pulmonary embolism (PE) prevalence in 235,393 total hip arthroplasty patients. Univariate analysis identified significant associations between PE and female gender, diabetes, smoking, dyspnea, CHF, COPD, hypertension (HT), bleeding disorders, disseminated cancer, steroid use, and functional health status. Multivariate analysis revealed male gender as protective, while COPD, hypertension, and disseminated cancer increased PE risk. Notably, smoking appeared protective. PE patients had higher return-to-operation rates (41.7% vs. 2.2%) but similar 30-day mortality (0.2% vs. 0.04%), though mortality's odds ratio was not significant.

CONCLUSIONS

Our findings suggest that certain patient characteristics, such as COPD and metastatic malignancy, significantly influence the likelihood of PE development.

Mid-term to Long-term Outcomes and Complications of Total Hip Arthroplasty in Patients Who Have Crowe IV Developmental Dysplasia of the Hip: A Systematic Review and Meta-Analysis

BACKGROUND

Severe forms of developmental dysplasia of the hip (DDH) in adulthood often lead to total hip arthroplasty (THA). This study aimed to evaluate the mid-term to long-term outcomes of THA in Crowe type IV DDH cases, which represent a technically challenging and complex patient group.

METHODS

PubMed, EMBASE, Web of Science, and Scopus were searched for observational studies and case series with over 100 months of mean follow-up on adult patients who had Crowe type IV DDH treated with THA. A total of 3,710 records were initially identified, leading to the inclusion of 24 studies in the final analysis. These studies were subjected to quality assessment using the National Institutes of Health (NIH) Quality Assessment tool. Various outcomes including revision rates, leg length discrepancy (LLD), Harris Hip Score (HHS), and complications like periprosthetic joint infections (PJI), dislocations, and nerve injuries were analyzed. A random effects model was employed for statistical analysis, with sensitivity analysis and meta-regression applied in cases of high heterogeneity.

RESULTS

The included studies assessed 1,024 hips with a mean follow-up of 11 years, revealing improvements in HHS and reductions in LLD post-THA. However, notable challenges were noted, including a 10.7% rate of intraoperative fractures, a 1.8% PJI rate, and a 5.8% dislocation rate. Osteolysis and aseptic loosening revisions were observed in 9.1 and 8% of cases, respectively. Heterotopic ossification (HO) occurred in 11.1% of patients. Nerve injury was reported in 4.2% of cases. With the use of meta-regression, some factors for observed heterogeneity were identified.

CONCLUSION

Total hip arthroplasty in Crowe type IV DDH patients presents notable challenges, but can lead to substantial long-term improvements in patient-reported outcomes.

Randomized Controlled Trial of a Novel Cementless vs. Cemented Total Knee Arthroplasty: Early Clinical and Radiographic Outcomes

OBJECTIVE

Previous cementless total knee arthroplasty (TKA) designs faced challenges with insufficient initial fixation on tibial side, resulting in inferior functional outcomes and survival rates. The Zoned Trabecular Bone Cementless Knee is a novel implant designed for cementless TKA which aims to achieve excellent initial fixation, promoting effective osseointegration. The aim of this research was to compare the early clinical and radiographic results of this cementless TKA with cemented TKA.

METHODS

Between September 2021 and April 2022, 64 patients (64 knees) were recruited in this prospective randomized controlled trial to receive either cementless 3D-printed trabecular metal TKA or a cemented posterior stabilized TKA. Preoperative and postoperative clinical evaluations, including the range of motion (ROM), Knee Society Score (KSS), and the Reduced Western Ontario and MacMaster Universities Score (WOMAC), were conducted and analyzed for comparison. Radiographs and computed tomography scans were utilized to assess the initial fixation. The complications between the two groups were also recorded and compared. Continuous data were analyzed for significance using independent-samples t-test or the Mann-Whitney U test and categorical data were analyzed using chi-squared or Fisher's exact test.

RESULTS

Both groups demonstrated significant enhancement at 12 months follow-up in the ROM compared with baseline (ROM: 94.7 ± 23.4 vs. 113.1 ± 12.3 in cementless group and 96.5 ± 14.7 vs. 111.0 ± 12.8 in cemented group, p < 0.05). However, no statistical differences were observed between the two groups in postoperative ROM, KSS, or WOMAC score. The radiographs and computed tomography scans showed similar results, including radiolucent lines and osteolysis in either femoral or tibial. Additionally, there was no statistical difference in the overall complication rate between the two groups. Notably, one patient in the cementless TKA group required revision for periprosthetic infection as the end point.

CONCLUSIONS

This novel 3D-printed trabecular metal cementless TKA achieved comparable clinical outcomes and initial fixation to cemented TKA in early stage. Longer-term examination is necessary to validate these results.

Outpatient vs. inpatient designation in total hip arthroplasty: can we predict who will require hospitalization?

INTRODUCTION

Following removal of total hip arthroplasty (THA) from the inpatient only (IPO) list by the Center for Medicare Services (CMS), arthroplasty surgeons face increased pressure to perform procedures on an outpatient (OP) basis. The purposes of the present study were to compare patients booked for THA as OP who required conversion to IP status postoperatively, to patients who were booked as, and remained OP, and to identify factors predictive of conversion from OP to IP status.

METHODS

We retrospectively reviewed all patients who underwent a primary THA at our institution between January 1, 2020 and April 26, 2022. All patients included were originally scheduled for OP surgery and were separated based on conversion to IP status postoperatively. Multiple regression analyses were used to determine the significance of all perioperative variables. Modeling via binary logistic regressions were used to determine factors predictive of status conversion.

RESULTS

Of 1,937 patients, 372 (19.2%) designated as OP preoperatively required conversion to IP status postoperatively. These patients had significantly higher facility discharge rates (P < 0.001) and 90-day readmission rates (P = 0.024). Patients aged 65 and older (P < 0.001), females (P < 0.001), patients with Black/African American race (P = 0.027), with a recovery room arrival time after 12 pm (P < 0.001), with a BMI > 30 kg/m2 (P = 0.001), and with a Charlson Comorbidity Index (CCI) ≥ 4 (P = 0.013) were Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation more likely to require conversion to IP designation. Marital status and time of procedure were also significant factors, as patients who were married (P < 0.001) and who were the first case of the day (P < 0.001) were less likely to be converted to IP.

CONCLUSION

Several factors were identified which could help determine appropriate hospital designation status at the time of surgical booking to ultimately avoid insurance claim denials. These included BMI, certain demographic factors, CCI ≥ 4, and patients 65 or older.

LEVEL III EVIDENCE

Retrospective Cohort Study.

Downregulation of TGF-β1 in fibro-adipogenic progenitors initiates muscle ectopic mineralization

In previous studies, we have demonstrated that stress response-induced high glucocorticoid levels could be the underlying cause of traumatic heterotopic ossification (HO), and we have developed a glucocorticoid-induced ectopic mineralization (EM) mouse model by systemic administration of a high dose of dexamethasone (DEX) to animals with muscle injury induced by cardiotoxin injection. In this model, dystrophic calcification (DC) developed into HO in a cell autonomous manner. However, it is not clear how DC is formed after DEX treatment. Therefore, in this study, we aimed to explore how glucocorticoids initiate muscle EM at a cellular and molecular level. We showed that DEX treatment inhibited inflammatory cell infiltration into injured muscle but inflammatory cytokine production in the muscle was significantly increased, suggesting that other non-inflammatory muscle cell types may regulate the inflammatory response and the muscle repair process. Accompanying this phenotype, transforming growth factor β1 (TGF-β1) expression in fibro-adipogenic progenitors (FAPs) was greatly downregulated. Since TGF-β1 is a strong immune suppressor and FAP's regulatory role has a large impact on muscle repair, we hypothesized that downregulation of TGF-β1 in FAPs after DEX treatment resulted in this hyperinflammatory state and subsequent failed muscle repair and EM formation. To test our hypothesis, we utilized a transgenic mouse model to specifically knockout Tgfb1 gene in PDGFRα-positive FAPs to investigate if the transgenic mice could recapitulate the phenotype that was induced by DEX treatment. Our results showed that the transgenic mice completely phenocopied this hyperinflammatory state and spontaneously developed EM following muscle injury. On the contrary, therapeutics that enhanced TGF-β1 signaling in FAPs inhibited the inflammatory response and attenuated muscle EM. In summary, these results indicate that FAPs-derived TGF-β1 is a key molecule in regulating muscle inflammatory response and subsequent EM, and that glucocorticoids exert their effect via downregulating TGF-β1 in FAPs.

Above-Knee Amputation Following Chronically Infected Total Knee Arthroplasty: Patient-Reported Satisfaction and Functional Outcomes

INTRODUCTION

Periprosthetic joint infection (PJI) that arises following total knee arthroplasty (TKA) can usually be resolved through surgical and antimicrobial therapy. However, in approximately 5% of cases, an infection that is chronic and persistent will require treatment by above-knee amputation (AKA). This study seeks to provide an enhanced understanding of patient functionality and satisfaction following this devastating complication of one of the most commonly performed surgeries in the world.

METHODS

A retrospective chart review of all patients who underwent an AKA as a result of PJI following TKA at our center between January 2000 and November 2023 was performed. Patients completed a post-TKA AKA functionality and satisfaction questionnaire, as well as the 12-Item Short Form Survey (SF-12). Of 27 eligible patients, 14 were contacted by phone for follow-up, 6 were deceased, 6 could not be reached, and 1 declined participation. The mean age at AKA was 62 years old (range, 43 to 85). Patients had an average of 5.5 procedures (range, 3 to 8) between primary TKA and AKA. The average follow-up time post-AKA was 38.5 months (range, 12 to 102).

RESULTS

Of the patients, 85.7% were satisfied with their AKA, 85.7% would choose AKA again, and 71.4% would have proceeded with AKA earlier in retrospect. Average SF-12 physical and mental component scores were 37.1 and 50.6, respectively.

DISCUSSION

Despite important limitations in functional and ambulatory status, the vast majority of patients who underwent an AKA following an infected TKA are satisfied with their amputation and would choose this treatment modality again if necessary, with many indicating they would do so at an earlier time point. In light of these results, the option of amputation should, when medically indicated, be discussed in a sensitive, but timely manner with patients undergoing treatment for recalcitrant PJI.

Medicaid Reimbursement for Total Hip and Knee Arthroplasty: A State-by-State Analysis Compared with Medicare

BACKGROUND

Medicare reimbursement for arthroplasty procedures has been declining, but little has been reported on Medicaid reimbursement. We sought to determine Medicaid reimbursement rates using state Medicaid data for nine arthroplasty procedure codes and compare them to Medicare rates.

METHODS

The Centers for Medicare & Medicaid Services physician fee schedule was used to collect Medicare reimbursement rates, and state Medicaid fee schedules were accessed to collect Medicaid rates for nine procedures encompassing primary and revision hip and knee arthroplasty surgery. State Medicare and Medicaid rates were compared to determine the mean dollar difference and dollar difference per relative value unit (RVU). A cost of living adjustment was performed using the Medicare Wage Index for each state. Coefficients of variation were calculated for each state to determine overall variability between the two systems.

RESULTS

The mean reimbursement rates for Medicaid were lower for eight of the nine codes used in the study. Medicaid reimbursed physicians an average of 11.3% less overall and 23.1% less when adjusted for cost of living. The amount of variability in the Medicare rates was low with a consistent coefficient of variation of 0.06, but was higher in the Medicaid rates with a range of 0.26 to 0.29 in the unadjusted rates and 0.34 to 0.37 in the adjusted rates. There was a mean $6.73 decreased reimbursement per RVU for Medicaid procedures.

CONCLUSION

For the most common arthroplasty procedures, Medicaid reimbursed physicians less than Medicare on average. Medicaid also demonstrated increased variability when compared to Medicare rates between states.

Peek@ZIF-8(CEL) as a Novel Bone Implant for Large Defect Repair and Enhanced Bone Healing via a Long-Term Stable Bioactive Releaser

The repair of large bone defects poses a significant challenge in orthopedics. Polyetheretherketone (PEEK) is a promising bone substitute, while it suffers a lack of bioactivity. Although several studies have been performed to further improve the bioactivities of PEEK by various surface modifications, PEEK offering long-term, multifaceted biofunctionalities remains still desired. In this study, we introduced metal-organic frameworks (MOFs), specifically ZIF-8 loaded with celecoxib (ZIF-8(CEL)), onto the PEEK surface through dopamine adhesion. The resulting PEEK@ZIF-8(CEL) aims to achieve long-term stable release of Zn ions and CEL for enhanced bone integration. Material characterization and biological experiments confirmed the successful integration of ZIF-8(CEL) onto PEEK and its positive biomedical effects, including creating a positive bone immunological environment and promoting bone growth. This study demonstrates the potential of PEEK@ZIF-8(CEL) as a novel repair material for large bone defects, offering a promising alternative in orthopedic applications.

Clinic of Hope: bridging infectious disease and orthopaedic surgery in prosthetic joint infection management

Prosthetic joint infections (PJIs) following total joint arthroplasty are a significant and costly complication. To address fragmented care typically seen with separate management, we established a combined infectious disease and orthopaedic surgery clinic at Duke Health in July 2020. This clinic focuses on patients experiencing acute deterioration or multiple PJI episodes, often at the stage where amputation is the only option offered. From July 2021 to March 2024, the clinic completed 974 visits with 319 unique patients. The clinic maintained a low no-show rate of 5.0%. Treatment plans included procedures such as debridement, antibiotics and implant retention (38%), as well as implant explantation and one-stage exchange (32% each), with amputation required in only 4% of cases. The integrated clinic model facilitated real-time, multidisciplinary care, improving patient outcomes and operational efficiency. This approach offers a promising model for managing complex infections.

A zirconia/tantalum biocermet: in vitro and in vivo evaluation for biomedical implant applications

A biocermet made of zirconia/20 vol% tantalum (3Y-TZP/Ta) is a new composite with exceptional capabilities due to a combination of properties that are rarely achieved in conventional materials (high strength and toughness, cyclic fatigue resistance and flaw tolerance, wear resistance, corrosion resistance, electrical conductivity, etc.). In this study, for the first time, the biomedical performance of a 3Y-TZP/Ta biocermet was evaluated in detail. Its in vitro biocompatibility was assessed using mesenchymal stem cell culture. The effectiveness of in vivo osteointegration of the biocermet was confirmed 6 months after implantation into the proximal tibiae of New Zealand white rabbits. In addition, the possibility of using magnetic resonance imaging (MRI) for medical analysis of the considered biocermet material was studied. The 3Y-TZP/Ta composite showed no injurious effect on cell morphology, extracellular matrix production or cell proliferation. Moreover, the implanted biocermet appeared to be capable of promoting bone growth without adverse reactions. On the other hand, this biocermet demonstrates artefact-free performance in MRI biomedical image analysis studies, making it more suitable for implant applications. These findings open up possibilities for a wide range of applications of these materials in orthopedics, dentistry and other areas such as replacement of hard tissues.

Addressing sagittal plane imbalance in primary total knee arthroplasty

Aims

Sagittal plane imbalance (SPI), or asymmetry between extension and flexion gaps, is an important issue in total knee arthroplasty (TKA). The purpose of this study was to compare SPI between kinematic alignment (KA), mechanical alignment (MA), and functional alignment (FA) strategies.

Methods

In 137 robotic-assisted TKAs, extension and flexion stressed gap laxities and bone resections were measured. The primary outcome was the proportion and magnitude of medial and lateral SPI (gap differential > 2.0 mm) for KA, MA, and FA. Secondary outcomes were the proportion of knees with severe (> 4.0 mm) SPI, and resection thicknesses for each technique, with KA as reference.

Results

FA showed significantly lower rates of medial and lateral SPI (2.9% and 2.2%) compared to KA (45.3%; p < 0.001, and 25.5%; p < 0.001) and compared to MA (52.6%; p < 0.001 and 29.9%; p < 0.001). There was no difference in medial and lateral SPI between KA and MA (p = 0.228 and p = 0.417, respectively). FA showed significantly lower rates of severe medial and lateral SPI (0 and 0%) compared to KA (8.0%; p < 0.001 and 7.3%; p = 0.001) and compared to MA (10.2%; p < 0.001 and 4.4%; p = 0.013). There was no difference in severe medial and lateral SPI between KA and MA (p = 0.527 and p = 0.307, respectively). MA resulted in thinner resections than KA in medial extension (mean difference (MD) 1.4 mm, SD 1.9; p < 0.001), medial flexion (MD 1.5 mm, SD 1.8; p < 0.001), and lateral extension (MD 1.1 mm, SD 1.9; p < 0.001). FA resulted in thinner resections than KA in medial extension (MD 1.6 mm, SD 1.4; p < 0.001) and lateral extension (MD 2.0 mm, SD 1.6; p < 0.001), but in thicker medial flexion resections (MD 0.8 mm, SD 1.4; p < 0.001).

Conclusion

Mechanical and kinematic alignment (measured resection techniques) result in high rates of SPI. Pre-resection angular and translational adjustments with functional alignment, with typically smaller distal than posterior femoral resection, address this issue.

Racial and Ethnic Disparities in Primary Total Knee Arthroplasty Outcomes: A Systematic Review and Meta-Analysis of Two Decades of Research

Racial disparities in outcomes following total knee arthroplasty (TKA) remain persistent. This systematic review and meta-analysis aims to comprehensively synthesize data between 2000-2020. An electronic search of studies was performed on PubMed, SCOPUS, and the Cochrane Library databases from January 1, 2000, and December 31, 2020. Random effects models were used to report unadjusted and adjusted estimates for a comprehensive list of care outcomes in TKA. 63 studies met PRISMA criteria. Black patients report greater odds of in-hospital mortality (odds ratio [OR]: 1.37, 95% CI: 1.00-1.59 (p = 0.049); adjusted OR [aOR]: 1.34, 95% CI: 1.09-1.64), in-hospital complications (OR: 1.31, 95% CI: 1.27-1.35), 30-day complications (aOR: 1.19, 95% CI: 1.07-1.33), infection (OR: 1.11, 95% CI: 1.07-1.16; aOR: 1.30, 95% CI: 1.16-1.46), bleeding (OR: 1.33, 95% CI: 1.03-1.71; aOR: 1.47, 95% CI: 1.23-1.75), peripheral vascular events (PVE) (aOR: 1.46, 95% CI: 1.11-1.92), length of stay (LOS) (OR: 1.20, 95% CI: 1.08-1.34), extended-LOS (aOR: 1.89, 95% CI: 1.53-2.33), discharge disposition (OR: 1.59, 95% CI: 1.29-1.96; aOR: 1.96, 95% CI: 1.70-2.25), 30-day (OR: 1.20, 95% CI: 1.13-1.27; aOR: 1.17 95% CI: 1.09-1.26) and 90-day (OR: 1.46, 95% CI: 1.17-1.82) readmission compared to White patients. Disparities in bleeding, extended-LOS, discharge disposition, PVE, and 30-day readmission were observed in Asian patients. Hispanic patients experienced disparities in extended LOS and discharge disposition, while Native-American patients had disparities in bleeding outcomes. Persistent racial disparities in TKA outcomes highlight a need for standardized outcome measures and comprehensive data collection across multiple racial groups to ensure greater healthy equity.

Impact of 25 Years of Mobile Health Tools for Pain Management in Patients With Chronic Musculoskeletal Pain: Systematic Review

BACKGROUND

Mobile technologies are increasingly being used in health care and public health practice for patient communication, monitoring, and education. Mobile health (mHealth) tools have also been used to facilitate adherence to chronic musculoskeletal pain (CMP) management, which is critical to achieving improved pain outcomes, quality of life, and cost-effective health care.

OBJECTIVE

The aim of this systematic review was to evaluate the 25-year trend of the literature on the adherence, usability, feasibility, and acceptability of mHealth interventions in CMP management among patients and health care providers.

METHODS

We searched the PubMed, Cochrane CENTRAL, MEDLINE, EMBASE, and Web of Science databases for studies assessing the role of mHealth in CMP management from January 1999 to December 2023. Outcomes of interest included the effect of mHealth interventions on patient adherence; pain-specific clinical outcomes after the intervention; and the usability, feasibility, and acceptability of mHealth tools and platforms in chronic pain management among target end users.

RESULTS

A total of 89 articles (26,429 participants) were included in the systematic review. Mobile apps were the most commonly used mHealth tools (78/89, 88%) among the included studies, followed by mobile app plus monitor (5/89, 6%), mobile app plus wearable sensor (4/89, 4%), and web-based mobile app plus monitor (1/89, 1%). Usability, feasibility, and acceptability or patient preferences for mHealth interventions were assessed in 26% (23/89) of the studies and observed to be generally high. Overall, 30% (27/89) of the studies used a randomized controlled trial (RCT), cohort, or pilot design to assess the impact of the mHealth intervention on patients' adherence, with significant improvements (all P<.05) observed in 93% (25/27) of these studies. Significant (judged at P<.05) between-group differences were reported in 27 of the 29 (93%) RCTs that measured the effect of mHealth on CMP-specific clinical outcomes.

CONCLUSIONS

There is great potential for mHealth tools to better facilitate adherence to CMP management, and the current evidence supporting their effectiveness is generally high. Further research should focus on the cost-effectiveness of mHealth interventions for better incorporating these tools into health care practices.

TRIAL REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO) CRD42024524634; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=524634.

The heavy burden and treatment challenges of fungal periprosthetic joint infection: a systematic review of 489 joints

BACKGROUND

Fungal periprosthetic joint infection (FPJI) is an infrequent but devastating complication that imposes a heavy burden on patients. At present, a consensus regarding the most optimal surgical option for patients with FPJI, the ideal duration of systemic antifungal treatment, and many other issues has not been reached.

METHODS

A comprehensive literature search was performed on the PubMed and Embase databases. The search criteria employed were as follows: (fungal OR candida OR mycotic) AND periprosthetic joint infection. Initially, the titles and abstracts were screened, and subsequently, studies deemed irrelevant or duplicative were eliminated. Following this, the complete texts of remaining articles were thoroughly examined. According to the inclusion and exclusion criteria, 489 joints in 24 articles were screened out. We further extracted the demographic characteristics (age, gender, body mass index, etc.), clinical presentation, fungal species, presence of bacterial coinfection, surgical methods, systemic and local antifungal therapy, and treatment outcomes. Subgroup data were analyzed according to fungal species and bacterial coinfection. Univariate logistic regression analysis was conducted to ascertain the risk factors associated with the infection recurrence.

RESULTS

A total of 506 fungi were identified within 489 joints. The most prevalent fungal species were Candida albicans (41.5%). Out of 247 joints (50.5%) presenting with concurrent fungal and bacterial infections. Among the initial surgical interventions, two-stage exchange was the most common (59.1%). The infection recurrence rates of DAIR, resection arthroplasty, two-stage, one-stage, and three-stage exchange were 81.4%, 53.1%, 47.7%, 35.0%, and 30%, respectively. The mean duration of systemic antifungal therapy was 12.8 weeks. The most common drugs used both in intravenous (55.9%) and oral therapy (84.0%) were fluconazole. The proportion of patients who used antifungal drugs after replantation (two-stage and three-stage) was 87.6%. 33.2% of cement spacer or fixed cement contained antifungal drugs, of which amphotericin B was the main choice (82.7%). FPJI caused by candida albicans (OR = 1.717, p = 0.041) and DAIR (OR = 8.433, p = 0.003) were risk factors for infection recurrence.

CONCLUSIONS

Two-stage exchange remains the most commonly used surgical approach. The reliability of one- and three-exchange needs further evaluation due to the small sample size. Antifungal-loaded cement spacers, and direct intra-articular injections of antimycotics after reimplatation should be strongly considered. Medication is not standardized but rather individualized according to microbiology and the status of patients.

Imaging mimickers of MSK infection

Along with clinical and laboratory findings, imaging has a significant role in the initial evaluation and treatment follow-up of a wide variety of infectious and non-infectious musculoskeletal (MSK) conditions. The imaging findings of many non-infectious MSK processes, such as inflammatory, metabolic, and degenerative arthropathies, complications of diabetes mellitus, osseous and soft tissue injuries, osteonecrosis, tumors, and tumor-like lesions may be nonspecific and often overlap with those found in MSK infections. In this article, the authors discuss the imaging findings of both frequent and rare mimickers of MSK infections, including potential distinguishing characteristics.

Maryland's Global Budget Revenue Program and Equitable Access to Esophagectomy for Esophageal Cancer

INTRODUCTION

We evaluated equity in access to esophagectomy after Maryland's 2014 "Global Budget Revenue" (GBR) implementation, which equalizes reimbursement rates irrespective of patient insurance and employs an annual hospital revenue ceiling to incentivize reductions in unnecessary resource utilization. We hypothesized that more traditionally underserved patients would undergo surgical treatment for esophageal cancers after GBR.

METHODS

Using Maryland's Health Services Cost Review Commission database, we retrospectively analyzed patient demographics, insurance statuses, inflation-adjusted hospital charges, postoperative outcomes, and discharge dispositions for esophagectomies for neoplasms between 2012 and 2018.

RESULTS

Four hundred eighty six patients were included: 22.0% (107) pre-GBR and 78.0% (379) post-GBR. The proportion of African-American patients increased post-GBR (5.6% versus 12.9%, P = 0.035) and subsequently exhibited year-over-year increases. While not statistically significant, the proportion of Medicaid patients increased from 4.7% to 10.0% (P = 0.085). The post-GBR era also saw patients from 10 new counties, six of which were in Maryland's bottom half of counties ranked by median household income, receive operative esophageal cancer treatment without losing representation from pre-GBR counties. Patient age and sex were comparable between the two groups, and there were no significant differences in mortality or 30-day readmissions. Inflation-adjusted hospital charges and length of hospital stay did not appreciably change post-GBR, including after adjusting for age, comorbidities, and surgical approach.

CONCLUSIONS

GBR increased access to esophagectomy for African-Americans, those insured by Medicaid, and those from lower socioeconomic status counties. Contrary to prior studies of outpatient and emergency room settings, we found the GBR program's goal of reduction of resource utilization and cost were not apparent in this complex surgical population.

Intensive physical activity following total hip arthroplasty increased the revision risk after 15 years: a cohort study of 973 patients from the Geneva Arthroplasty Register

BACKGROUND AND PURPOSE

Younger recipients of total hip arthroplasty (THA) highly prioritize returning to preoperative levels of physical activity (PA). Surgeons have tended to give cautious advice concerning high-impact sports participation, but there have been few long-term studies. The purpose of our study was to investigate the risk of revision arthroplasty in relation to postoperative PA levels.

METHODS

Patients registered in the Geneva Arthroplasty Register (GAR) who had elective THA when they were aged < 65 years were studied. Postoperative PA was collected prospectively 5-yearly using the UCLA activity scale. Cox proportional hazards models were used to estimate associations between PA and risk of revision THA.

RESULTS

Amongst 1,370 eligible subjects, median age at THA 58 years (interquartile range 51-61), UCLA scores were available for 973 (71%). During follow-up over 15 years, there were 79 revisions, giving a cumulative risk of 7.4% (95% confidence interval [CI] 5.8-9.4). After adjusting for covariates, we found an increased risk of revision for each unit increase in postoperative PA (HR 1.2, CI 1.1-1.4), and among people performing the most intensive PA (HR 2.7, CI 1.3-5.6) compared with those who were inactive.

CONCLUSION

The overall risk of revision was small but intensive and moderate PA may be associated with an increased risk of revision.

Polyethylene liner dissociation in total hip arthroplasty: a retrospective case-control study on a single implant design

BACKGROUND

Modular acetabular components for total hip arthroplasty (THA) provide intraoperative flexibility; however, polyethylene liner dissociation may occur. This study aimed to examine the incidence and causes of liner dissociation associated with a specific acetabular component design at a single centre.

MATERIALS AND METHODS

A retrospective analysis of 7027 patients who underwent primary THA was performed to identify isolated liner dislocations. Patient demographics, clinical presentations, surgical and implant details, and both radiographic and computed tomography (CT) findings were analysed. Patients with liner dislocation were matched to a control group via 2:1 propensity score matching, and a logistic regression analysis was employed to identify associated risk factors.

RESULTS

A total of 32 patients (0.45%) experienced liner dislocation at a mean 71.47 ± 60.10 months post surgery. Significant factors contributing to dislocations included the use of a conventional compared with a highly crosslinked polyethylene component (p = 0.049) and screw fixation (p = 0.028). Radiographic and CT analysis highlighted the importance of proper component orientation, revealing that patients experiencing dislocations demonstrated significantly lower acetabular cup anteversion angles (p = 0.001) compared with the control group. Impingement and malposition, identified in 41% and 47% of the cases, respectively, further underscored the multifactorial nature of dislocation risks.

CONCLUSIONS

While the overall rate of polyethylene liner dislocation was low, the findings of this study highlight the importance of appropriate cup placement to decrease the risk of dissociation. It further substantiates the influence of impingement and malposition in liner displacement, with increased mechanical stress exerted on the locking mechanism under adverse conditions and the potential risk increase due to screw placement.

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.

Challenges of Hip and Knee Arthroplasty in Patients With Osteopetrosis

Osteopetrosis is a rare metabolic bone disease, characterized by dysfunction of osteoclasts, resulting in increased bone density and brittleness leading to pathological fractures and bone deformities. Hip and knee osteoarthritis (OA) are common long-term complications in patients with osteopetrosis. Joint arthroplasty surgery remains an effective and recommended treatment for these patients with an end-stage OA because it provides favorable outcomes. However, in osteopetrosis, joint arthroplasty surgery carries an increased risk of complications, and specific preoperative and perioperative considerations are required to deal with the technical challenges related to the disease. The aim of this article was to review some of the key aspects of osteopetrosis, provide technical recommendations, and answer clinically relevant questions related to hip and knee arthroplasty surgery.

Patients' joint perception after anterior cruciate ligament reconstruction as a reliable patient-reported outcome measure

PURPOSE

This study aims to evaluate and compare patients' joint perception (PJP) with other commonly employed patient-reported outcome measures (PROMs) in a cohort of patients following anterior cruciate ligament reconstruction (ACLR).

METHODS

A retrospective study was conducted on 108 patients who underwent ACLR between 2017 and 2021, with complete data available for visual analogue scale (VAS) pain, PJP, Forgotten Joint Score (FJS), Tegner Activity Scale, Lysholm Knee Scoring Scale, Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI), Single Assessment Numeric Evaluation (SANE), Cincinnati Knee Rating System (CKRS) and The Hospital for Special Surgery Anterior Cruciate Ligament Satisfaction Survey (HSS ACL-SS) at a mean follow-up of 3 years. Spearman's rank-order correlation was used to determine the correlations between clinical scores. A receiver operating characteristic (ROC) curve analysis was used to assess the discriminatory power of the chosen PROMs in detecting natural joint perception. Natural joint perception was defined as patients responding 'like a native or natural joint' or PJP = 1. This study hypothesized that PJP would demonstrate significant correlations with established PROMs, indicating its reliability and validity as a tool for assessing outcomes following ACLR.

RESULTS

PJP showed significant correlations with all the reported PROMs, suggesting its potential as a valid and reliable assessment tool for evaluating ACLR outcomes. The ROC curve analysis indicated a good area under the curve for identifying natural joint perception using various PROMs. According to the PJP, nearly 20% of patients reported natural joint perception.

CONCLUSION

This study evaluates PJP as a reliable tool for assessing patient outcomes following ACLR. Its significant correlation with other established PROMs underscores its potential as a valuable addition to the existing array of PROMs in ACLR.

LEVEL OF EVIDENCE

Level III.

What features of stem increase the risk of intraoperative femoral fracture during cementless primary hip arthroplasty?

INTRODUCTION

Cementless fixation has become increasingly popular in hip arthroplasty due to its shorter operation time, easier technique, biologic fixation, and avoidance of bone cement implantation syndrome compared to cemented fixation. However, intraoperative periprosthetic femoral fracture (IOPFx) is a disconcerting complication during cementless hip arthroplasty. Our purpose was to identify the features of cementless stem that increase the risk of IOPFx during primary hip arthroplasty.

MATERIALS AND METHODS

We retrospectively reviewed all 4806 hip arthroplasties that was performed in a single institution from May 2003 to December 2020. Age at the index arthroplasty, sex, body mass index, physical status, ambulatory function, side of the operation, operational history, cause of the index arthroplasty, type of arthroplasty, surgical approach, surgeon, implant information, and events during the operation were investigated. The shoulder geometry and length of stem were also reviewed. The event of interest was narrowed down to IOPFx among various records of intraoperative events.

RESULTS

We found IOPFx of 2.6% among all the hips operated with cementless stem. In the multivariable analysis, female (OR = 1.52), childhood hip disease (OR = 2.30), stove-pipe femur (OR = 2.43), combined approach (OR = 2.60), and standard length of stem (OR = 1.59) were found to be significant risk factors of IOPFx.

CONCLUSIONS

In conclusion, a stem with a standard length is significantly associated with risk of IOPFx compared to a shortened stem. These findings highlight the importance of careful consideration in terms of the risk of IOPFx when standard length cementless stem is chosen.

Antithrombotic prophylaxis following total knee arthroplasty: a level I Bayesian network meta-analysis

INTRODUCTION

Venous thromboembolism (VTE) is a major concern following total knee arthroplasty (TKA). The optimal pharmacological prophylaxis remains, however, controversial. The present investigation compared several non-vitamin K antagonist oral anticoagulants commonly employed as VTE prophylaxis following TKA. A Bayesian network meta-analysis was conducted to compare apixaban, aspirin, dabigatran, edoxaban, enoxaparin, fondaparinux, and rivaroxaban. The outcomes of interest were to compare the rate of deep venous thrombosis (DVT), pulmonary embolism (PE), and major and minor haemorrhages.

METHODS

This study was conducted according to the PRISMA Extension Statement for Reporting of Systematic Reviews Incorporating Network Meta-Analyses of Health Care Interventions. In March 2024, PubMed, Web of Science, and Google Scholar were accessed with no time constraints. All randomised controlled trials (RCTs) comparing two or more drugs for the prevention of VTE following TKA were considered for inclusion.

RESULTS

Data from 29,678 patients were collected. Of them, 67% (19,884 of 29,678 patients) were women. The mean age of the patients was 66.8 ± 2.8 years, and the mean BMI was 29.2 ± 1.5 kg/m2. There was comparability in age, sex, and BMI at baseline. Apixaban 5 mg, dabigatran 220 mg, and rivaroxaban 10 mg were the most effective in reducing the rate of DVT. Apixaban 5 mg, enoxaparin 60 mg, and rivaroxaban 40 mg were the most effective in reducing the rate of PE. Apixaban 5 mg, rivaroxaban 10 mg, and apixaban 10 mg were associated with the lowest rate of major haemorrhages. Apixaban 5 mg and 20 mg, and dabigatran 220 mg were associated with the lowest rate of minor haemorrhages.

CONCLUSION

Administration of apixaban 5 mg demonstrated the best balance between VTE prevention and haemorrhage control following TKA.

LEVEL OF EVIDENCE

Level I, network meta-analysis of RCTs.

Monte Carlo-based in-depth morphological analysis of medullary cavity for designing personalized femoral stem

Background

The design of femoral stem prostheses requires a precise understanding of the femoral marrow cavity. Traditional measurements of morphological parameters in the upper femur, particularly the medullary cavity and cortical region, are primarily based on coronal and sagittal axes, which may not fully capture the true three-dimensional structure of the femur.

Methods

Propose a Monte Carlo-based method for a more comprehensive analysis of the femoral marrow cavity, using CT scans of femurs from a selected group of patients. The study aimed to define and calculate anatomically semantic morphological parameters to enhance the understanding of the femoral marrow cavity's anatomical morphological changes, ultimately improving the design and clinical selection of femoral stem prostheses. To enhance the accuracy of femoral stem prosthesis design, this study aims to develop a Monte Carlo-based method for a more comprehensive analysis of the femoral marrow cavity. The proposed method transforms the non-random problem of determining cross-sectional size into a random issue, allowing for the calculation of the size of the medullary cavity and cortical region. Anatomically semantic morphological parameters are then defined, calculated, and analyzed.

Results

The experimental results indicate that the newly defined parameters complement existing ones, providing a more rational scientific basis for understanding the anatomical morphological changes of the femoral marrow cavity.

Conclusion

This research offers essential scientific theoretical support for improved morphologic research, design, and clinical selection of femoral stem prostheses. It holds significant importance and application value in clinical practice, contributing to a more accurate and comprehensive understanding of femoral anatomy for prosthetic design.

Outcomes of Dual Mobility Versus Fixed Bearing Components in Revision Total Hip Arthroplasty: A Systematic Review and Meta-Analysis

AIMS

Dual mobility (DM) implants have received increasing interest in revision surgery due to their increased stability. The aim of this systematic review was to compare outcomes of DM versus conventional fixed bearing (FB) implants in revision Total Hip Arthroplasty (r-THA).

METHODS

A comprehensive search was performed using the PubMed, Embase, and MEDLINE databases between January 2000 and 2023. Outcome measures included re-revision due to dislocation, re-revision for other causes, all-cause re-revision, total complication rate, and functional outcome measures. The Methodological Index for Non-Randomized Studies (MINORS) assessment tool was used to evaluate methodological quality and the risk of bias. A pooled meta-analysis was conducted, with an assessment of heterogeneity using the Chi-square and Higgins I2 tests. A further sub-group analysis was performed between DM implants and larger femoral head (> 36 mm) FB implants.

RESULTS

A total of 13 studies met the final inclusion criteria, with an overall number of 5,004 r-THA hips included (2,108 DM and 2,896 FB). The DM implants had significantly lower odds of re-revision due to dislocation (OR [odds ratio] 0.38, P < 0.001), aseptic loosening (OR 0.54, P = 0.004), and all-cause re-revision (OR 0.55, P < 0.001) compared to FB implants. No significant difference was seen in the odds of re-revision due to periprosthetic joint infection (PJI) (OR 0.99, P = 0.94) or periprosthetic fracture (OR 0.59, P = 0.13) between the two groups. The total number of complications showed an odds benefit in favor of DM implants (OR 0.43, P < 0.001). In the subgroup analysis, there was no significant difference in the odds of re-revision due to dislocation (OR 0.69, P = 0.11) between DM and larger femoral head FB implants.

CONCLUSION

Based upon current literature, it appears DM implants are an effective modality for reducing dislocation following r-THA with lower complication rates compared to FB implants. However, further prospective randomized controlled trials (RCTs) with longer term follow up are required.