A reduction in tumor volume exceeding 65% predicts a good histological response to neoadjuvant chemotherapy in patients with Ewing sarcoma.

OBJECTIVE: No consensus exists for tumor volume response criteria in patients with Ewing sarcoma. This study aimed to identify an optimal cutoff for predicting a good histological response by analyzing tumor volume changes and tumor necrosis after neoadjuvant chemotherapy. MATERIALS AND METHODS: We performed a retrospective analysis of 184 Ewing sarcoma patients, analyzing tumor volume changes before and after neoadjuvant chemotherapy. Patients were divided into two groups based on histological response: good (tumor necrosis ≥ 95%) and poor (tumor necrosis < 95%) responders. The receiver operating characteristic (ROC) area under the curve (AUC) method was used to determine the optimal thresholds for predicting the histological response. Additionally, the prognostic value of this cutoff for relapse-free survival was assessed. RESULTS: Out of 184 patients, 83 (45%) had tumor necrosis ≥ 95%, while 101 (55%) had tumor necrosis < 95%. ROC analysis identified the optimal cutoff for a good histological response as over 65% tumor volume reduction (AUC = 0.69; p < 0.001). Patients with volume reduction of ≥ 65% had a higher likelihood of a good histological response than those with lesser reductions (p = 0.004; odds ratio = 2.61). Multivariable analysis indicated a correlation between poor histological response and reduced relapse-free survival (hazard ratio = 2.17; p = 0.01), while tumor volume reduction itself did not impact survival. CONCLUSION: We reported that a tumor volume reduction of ≥ 65% was able to predict a good histological response in Ewing sarcoma patients. We recommend preoperative tumor volume assessment to identify patients at greater risk for poor histological response who could benefit from more intensive chemotherapy protocols or additional radiotherapy.

Total knee arthroplasty survival rates are lower in younger men, as well as rheumatoid patients and after previous high-tibial osteotomy: A registry study.

PURPOSE: The purpose of this study was to investigate if patient's gender significantly affected the long-term outcome of patients undergoing total knee arthroplasty (TKA) and to provide a cross-gender comparison of a large patient sample from a single regional register. METHODS: The Registry of Prosthetic Orthopedic Implant of Emilia Romagna (RIPO) investigated all primary TKAs performed from July 2000 to December 2020 by collecting data of men and women separately. Primary bicompartmental and tricompartmental TKAs were included. The survival rates and the reasons for revision were assessed to check if any other factor could have influenced implant failure. RESULTS: In total, 66,032 TKAs were included and analysed, comprising 46,774 women and 19,258 men. The 15-year Kaplan-Meier survival percentage was 93.6% for women and 92.5% for men (p = 0.001). Men exhibited a higher revision risk following primary TKA (p = 0.012), particularly when the primary diagnosis was arthritis resulting from rheumatic disorders (p = 0.018) and arthritis following high-tibial osteotomy (p = 0.024). Failure risk was also higher for men below the age of 60 years (p = 0.038). CONCLUSION: The long-term outcome in TKA showed significant differences between men and women, with a significantly lower survival rate in men at 15 years, especially when they are under 60 years old or with a diagnosis of rheumatic disorders or arthritis following high-tibial osteotomy. It is necessary to design specific studies to have relevant data concerning gender differences in prosthetic surgery and to customise treatments to improve outcome and patient satisfaction. LEVEL OF EVIDENCE: Level III.

Malawer type I/V proximal humerus reconstruction after tumor resection: a systematic review.

BACKGROUND: Several reconstruction methods exist for Malawer type I/V proximal humerus reconstruction after bone tumor resection; however, no consensus has been reached regarding the preferred methods. METHODS: We conducted a literature search on various types of proximal humerus oncologic reconstruction methods. We collected data on postoperative functional outcomes assessed based on Musculoskeletal Tumor Society (MSTS) scores, 5-year reconstruction survival rates, and complications. We calculated each reconstruction's weighted mean based on the sample size and standard errors. Complications were categorized based on the Henderson classification. Based on these integrated data, our primary objective is to propose an optimal strategy for proximal humerus reconstruction after bone tumor resection. RESULTS: We examined various reconstruction techniques, including modular prosthesis (752 patients in 21 articles), osteoarticular allograft (142 patients in six articles), allograft prosthesis composites (236 patients in 12 articles), reverse shoulder total arthroplasty (141 patients in 10 articles), composite reverse shoulder total arthroplasty (33 patients in four articles), claviculo-pro-humero technique (51 patients in six articles), and cement spacer (207 patients in four articles). Weighted mean MSTS scores were: modular prosthesis (73.8%), osteoarticular allograft (74.4%), allograft prosthesis composites (79.2%), reverse shoulder total arthroplasty (77.0%), composite reverse shoulder total arthroplasty (76.1%), claviculo-pro-humero technique (75.1%), and cement spacer (69.1%). Weighted 5-year reconstruction survival rates were modular prosthesis (85.4%), osteoarticular allograft (67.6%), allograft prosthesis composites (85.2%), reverse shoulder total arthroplasty (84.1%), and cement spacer (88.0%). Reconstruction survival data was unavailable for composite reverse shoulder total arthroplasty and claviculo-pro-humero technique. Major complications included shoulder joint instability: modular prosthesis (26.2%), osteoarticular allograft (41.5%), allograft prosthesis composites (33.9%), reverse shoulder total arthroplasty (17%), composite reverse shoulder total arthroplasty (6.1%), claviculo-pro-humero technique (2.0%), and cement spacer (8.7%). Aseptic loosening of the prosthesis occurred: modular prosthesis (3.9%) and reverse shoulder total arthroplasty (5.7%). Allograft fracture was observed in 54.9% of patients with osteoarticular allograft. CONCLUSION: The complication profiles differed among reconstruction methods. Weighted mean MSTS scores exceeded 70% in all methods except cement spacer, and the 5-year reconstruction survival rate surpassed 80% for all methods except osteoarticular allograft. Proximal humerus reconstruction after bone tumor resection should consider potential complications and patients' individual factors.

Risk of complications and implant survival of surgical treatment of proximal femoral metastasis: a meta-analysis.

PURPOSE: The patients with femoral metastasis in the inter- or subtrochanteric area could be treated with intramedullary nailing or prosthetic reconstruction, however, it is controversial which surgical treatment could offer less complications and implant failure. Our purpose was to define the risk of complications and implant survival in patients treated with intramedullary nailing or prosthetic reconstruction. METHODS: We analyzed studies reporting the risk of complications, reoperations and removal of the implant in patients treated with intramedullary nailing, hemiarthroplasty, arthroplasty or megaprosthesis. RESULTS: We analyzed 27 studies (1346 patients) reporting patients treated with intramedullary nail (51%), hemiarthroplasty (15%), arthroplasty (2%), megaprosthesis with (25%) or without (7%) acetabular component. No difference was found in the overall risk of complications between patients treated with intramedullary nailing 6%, hemiarthroplasty or total hip arthroplasty 7% and megaprosthesis 11% (p = 0.23). However, patients treated with megaprosthesis had increased risk of reoperation due to infection (70%), compared to the patients treated with intramedullary nail (13%), and patients treated with hemiarthroplasty or total hip arthroplasty (23%) (p = 0.02). Revision due to disease progression was required in 61% of the patients treated with intramedullary nail, but not in patients treated with hemiarthroplasty, total arthroplasty, and megaprosthesis (p = 0.03). CONCLUSION: Patients treated with megaprosthesis had higher risk of reoperation due to infection, while patients treated with intramedullary nailing had higher risk of revision due to disease progression. Regarding patients treated with megaprosthesis, the risk of reoperation due to dislocation was higher in those treated with acetabular component.

Similar complications, implant survival, and function following modular prosthesis and allograft-prosthesis composite reconstructions of the proximal femur for primary bone tumors: a systematic review and meta-analysis.

PURPOSE: There is a lack of consensus regarding the best type of reconstruction of the proximal femur following bone tumor resection. The objective of this study was to analyze the complication risks, implant survival, and functional outcomes following modular prosthesis (MP) and allograft-prosthesis composite (APC) reconstruction of the proximal femur after primary bone tumor resections. METHODS: We performed a search in the PubMed and Scopus libraries, obtaining 1 843 studies. We included studies reporting functional outcomes, complications, and implant survival of proximal femur reconstruction with MP or APC following primary bone tumor resection with a 2-year minimum follow-up. We excluded studies analyzing metastatic patients or studies with pooled data in which it was impossible to separate the data of patients with primary bone tumors from those with bone metastases. RESULTS: We analyzed 18 studies (483 patients) reporting on 234 (48%) patients with MP reconstruction and 249 (52%) patients with APC reconstruction. The risk of complications was similar in patients with MP reconstruction (29%; 95% CI [0.11; 0.47]) and APC reconstruction (36%; 95% CI [0.24; 0.47]) (p = 0.48). Implant survival following MP reconstruction ranged from 81 to 86% at 5 years, 75 to 86% at 10 years, and 82% at 15 years. Implant survival following APC reconstruction ranged from 86 to 100% at 5 years and 86% at 10 years, and 86% at 15 years. Functional outcomes following MP reconstruction and APC reconstruction ranged from 24.0 to 28.3 and from 21.9 to 27.8, respectively. CONCLUSION: Patients with primary bone tumor of the proximal femur who underwent MP or APC reconstruction seem to have similar complication risks, implant survival, and functional outcomes.

The Prognostic Value of Serum Biomarkers for Survival of Children with Osteosarcoma of the Extremities.

BACKGROUND: Osteosarcoma is a highly aggressive malignant bone tumor that affects mainly adolescents and young adults. We analyzed serum biomarkers for their prognostic significance in children with osteosarcoma. METHODS: In this retrospective study, we investigated the prognostic factors in 210 children who were treated for appendicular osteosarcoma, including patient age and sex, tumor site and size (≥8 cm or <8 cm), presence of metastasis, chemotherapy-induced tumor necrosis, serum levels of alkaline phosphatase (AP), C-reactive protein, serum hemoglobin, lactate dehydrogenase, erythrocyte sedimentation rate (ESR), leukocyte counts, platelet count, and neutrophil-lymphocyte ratio. RESULTS: A multivariate Cox regression model showed that high level of AP [HR of 1.73; 95% CI, 1.02 to 2.94], poor chemotherapy-induced tumor necrosis [HR of 2.40; 95% CI, 1.41 to 4.08] and presence of metastases at presentation [HR of 3.71; 95% CI, 2.19 to 6.29] were associated with poor prognosis at 5 years (p < 0.05). Inadequate surgical margins [HR 11.28; 95% CI, 1.37 to 92.79] and high levels of ESR [HR 3.58; 95% CI, 1.29 to 9.98] showed a greater risk of local recurrence at 5 years follow-up (p < 0.05). CONCLUSIONS: AP and ESR can identify osteosarcoma-diagnosed children with a greater risk of death and local recurrence, respectively.

Identifying patient subgroups with different trends of patient-reported outcomes (PROMs) after elective knee arthroplasty.

BACKGROUND: Patient-reported outcome measures (PROMs) are increasingly being used to assess the effectiveness of elective total knee arthroplasty (TKA). However, little is known about how PROMs scores change over time in these patients. The aim of this study was to identify the trajectories of quality of life and joint functioning, and their associated demographic and clinical features in patients undergoing elective TKA. METHODS: A prospective, cohort study was conducted, in which PROMs questionnaires (Euro Quality 5 Dimensions 3L, EQ-5D-3L, and Knee injury and Osteoarthritis Outcome Score Patient Satisfaction, KOOS-PS) were administered to patients at a single center undergoing elective TKA before surgery, and at 6 and 12 months after surgery. Latent class growth mixture models were used to analyze the patterns of change in PROMs scores over time. Multinomial logistic regression was used to investigate the association between patient characteristics and PROMs trajectories. RESULTS: A total of 564 patients were included in the study. The analysis highlighted differential patterns of improvement after TKA. Three distinct PROMs trajectories were identified for each PROMs questionnaire, with one trajectory indicating the most favorable outcome. Female gender appears to be associated with a presentation to surgery with worse perceived quality of life and joint function than males, but also more rapid improvement after surgery. Having an ASA score greater than 3 is instead associated with a worse functional recovery after TKA. CONCLUSION: The results suggest three main PROMs trajectories in patients undergoing elective TKA. Most patients reported improved quality of life and joint functioning at 6 months, which then stabilized. However, other subgroups showed more varied trajectories. Further research is needed to confirm these findings and to explore the potential clinical implications of these results.

The Prognostic Value of the Serum Level of C-Reactive Protein for Survival of Children with Ewing's Sarcoma.

The purpose of the present study was to evaluate the prognostic role of C-reactive protein (CRP) in children with Ewing's sarcoma. We conducted a retrospective study on 151 children undergoing multimodal treatment for Ewing's sarcoma in the appendicular skeleton from December 1997 to June 2020. Univariate Kaplan-Meier analyses of laboratory biomarkers and clinical parameters showed that CRP and metastatic disease at presentation were poor prognostic factors associated with overall survival and disease recurrence at 5 years (p < 0.05). A multivariate Cox regression model showed that pathological CRP (≥1.0 mg/dL) [HR of 3.67; 95% CI, 1.46 to 10.42] and metastatic disease [HR of 4.27; 95% CI, 1.58 to 11.47] were associated with a higher risk of death at 5 years (p < 0.05). In addition, pathological CRP (≥1.0 mg/dL) [HR of 2.66; 95% CI, 1.23 to 6.01] and metastatic disease [HR of 2.56; 95% CI, 1.13 to 5.55] were associated with a higher risk of disease recurrence at 5 years (p < 0.05). Our findings demonstrated that CRP was associated with the prognosis of children with Ewing's sarcoma. We recommend pre-treatment measurement of the CRP in order to recognize children with Ewing's sarcoma who are at greater risk of death or local recurrence.

Comparison of single taper and dual taper versions of the same stem design in total hip arthroplasty for primary osteoarthritis.

BACKGROUND: In total hip arthroplasty (THA), the outcomes of single taper (ST) and dual taper (DT) versions of the same stem design have been scarcely studied. A registry study comparing ST and DT versions of the same stem design was designed, aiming to assess: (1) the survival rates and the hazard ratios for failure; (2) the survival rates and the hazard ratios for failure using stem-focused endpoints. MATERIAL AND METHODS: A regional arthroplasty registry was interrogated about stem designs with ST and DT versions in cementless THAs performed for primary osteoarthritis. Only the same cup and ceramic-on-ceramic bearings were included: the DT stems had a titanium-on-titanium modularity. Demographic and implant features were recorded. Survival rates and hazard ratios were evaluated and compared. Stem-focused endpoints were also investigated. RESULTS: A total of 5359 THAs were included, with three stem designs. The two versions of every stem showed different demographics and implant-related features: ST versions were preferentially implanted in heavier young men. For each stem, the two versions had similar survival rates at 5 years (p = 0.076; p = 0.319; p = 0.616) and similar adjusted hazard ratios for failures (p = 0.084; p = 0.308; p = 0.729). When stem-focused endpoints were adopted, the ST and DT versions of the three stems achieved similar survival rates (p = 0.710; p = 0.784; p = 0.983) and similar adjusted hazard ratios (p = 0.647; p = 0.858; p = 0.787). Three neck breakages occurred (0.0007% of all the modular implants). CONCLUSIONS: ST and DT versions of the same stem design did not show any differences in terms of survival rates and hazard ratios for failures at 5 years. LEVEL OF EVIDENCE: IV.

Age and Sex Influence the Use of Modular Femoral Components in Total Hip Arthroplasty Performed for Primary Osteoarthritis.

The impact of age and sex on femoral component choices in modular total hip arthroplasty (THA) is still unknown. A regional arthroplasty registry was interrogated about a modular stem in THA performed for primary osteoarthritis, with the aims to assess the influence of age and sex on stems sizes and neck choices. A total of 6830 THAs were included: all THAs had a modular stem (with 15 necks and 27 combinations per side). Patients were stratified by age in decades and sex. Necks were grouped according to the type of correction. The percentage of larger stem sizes increased in males and in elder patients (p < 0.001). Standard necks were overrepresented in males aged 40-59 and underrepresented in males aged 70 or older (p < 0.001). Half of the necks provided other corrections than standard or offset, especially in males aged 40-49 and females aged 70 or older (p < 0.001). Offset necks were predominant in elder patients (p < 0.001). Version-correcting necks were prevalent in younger males and older females (p < 0.001). Varus necks were implanted in one-third of the cases. The four commonest necks showed age and sex specific patterns. In the registry, age and sex impacted stem size and neck choices in THA performed for primary osteoarthritis.

Mid-term outcomes of revision hip arthroplasty due to titanium modular neck failure.

INTRODUCTION: The current strategy for modular neck failures in total hip arthroplasty (THA) is calibrated on CrCo neck failures. Stem revision is usually required, but the procedure is challenging and achieves modest outcomes (up to 20% of re-revisions at short-term). No study reports revision strategies and outcomes after Ti neck failures. Aims of the study were to evaluate: (1) demographic and implant features of the cohort to be revised, (2) intra-operative findings and surgical revision strategies and (3) clinical and radiological post-revision outcomes. MATERIALS AND METHODS: Hospital database was enquired about revisions due to Ti neck failures in primary THAs. Sixty-five revisions were enrolled (all with the same modular system). Neck exchange was attempted as the first-line treatment. Patients were clinically and radiographically evaluated after revision. RESULTS: The revision cohort encompassed fatigue neck fractures occurred 4.4 ± 2.6 years after THA: patients < 65 years and/or > 80 kg (98.5%) were predominant. Fifty-three neck exchanges were performed (81.5%). Eleven failures required stem revisions (16.9%), generally due to demanding neck extraction. Six complications occurred after neck exchange (11.3%), among them 2 acute infections requiring surgery (3.8%). Among stem revisions, one aseptic loosening and one neck re-fracture (18.5%) required re-revisions. At a mean follow-up of 7.1 ± 4 years, the neck exchange cohort achieved a mean HHS of 89.1 ± 6.3 (stem revisions: 84.1 ± 10.9). CONCLUSIONS: Revisions for Ti neck failures were predominantly performed due to fatigue fractures. In case of failures, neck exchange is a feasible procedure in most of the cases, with good outcomes at 7 years. LEVEL OF EVIDENCE: Level IV, retrospective case series.

A Modular Head-Neck Adapter System and Ceramic Heads in Revision Hip Arthroplasty: A Registry Study on 354 Implants.

BACKGROUND: Five- to 10-year outcomes of a modular head-neck adapter system with ceramic heads in revision hip arthroplasty on large populations are still lacking. A registry study about modular adapter system with Delta ceramic head in revisions was designed, aiming to assess (1) the survival rates of the device, (2) the reasons for re-revisions of the device, and (3) a comparison to factory assembled titanium sleeve and Delta head cohort in revision hips. METHODS: Using a regional arthroplasty registry, we investigated the modular adapter system with a ceramic head in revision hips. Demographics, implant features, and reasons for revision were recorded. Survival rates and reasons for re-revision were assessed. The modular adapter system with the ceramic ball was compared to a factory-assembled ceramic titanium-sleeved head in revisions, acting as a control group. There were 354 revisions included at a mean follow-up of 5 years (range, 0 to 13). RESULTS: The 5- and 7-year survival rates were 87.9% and 86.9%, respectively. Dislocations (2.8%) and cup aseptic loosening (4.2%) were the 2 most frequent reasons for re-revision. No breakage of the adapter system or the ceramic head occurred. A femoral neck failed (0.3%). No implant features, offset (P = .088) or skirted (P = .870) tapers, impacted on failures. No differences between the 2 cohorts were found regarding survival rates (P = .696) and reasons for re-revision (dislocations, P = .983; cup aseptic loosening, P = .296). CONCLUSION: The modular head neck adapter system with a ceramic head seems to be a valid option in revisions at 5 and 7 years, without additional risk of implant breakage in this registry.

Cup Overhanging in Anatomic Socket Position or High Hip Center of Rotation in Total Hip Arthroplasty for Crowe III and IV Dysplasia: A CT-Based Simulation.

Cup overhanging in total hip arthroplasty is a predisposing factor to iliopsoas impingement. In dysplastic hips, cup implantation was simulated in an anatomic hip center of rotation (AHCR) and in high hip center (HHCR). We sought to assess: (1) the percentage of prominent cups; (2) quantify the cup protrusion at different sites on frontal, axial and sagittal views. In 40 Crowe III-IV hips, using a 3D CT-based planning software, cup planning in AHCR and HHCR (CR height ≥ 20 mm) was performed for every hip. Cup prominence was assessed on every plane. HHCR cups were less anteverted (p < 0.01), less medialized (p < 0.001) and less caudal (p = 0.01) than AHCR sockets. AHCR cups were more frequently prominent on at least one plane (92.5% vs. 77.5%), with minimal agreement between the two configurations (k = 0.31, p = 0.07). AHCR cups protruded more than HHCR sockets in the sagittal (p = 0.02) and axial planes (p < 0.001). Axially, at the center of the cup, prominence 6−11 mm occurred in nine (22.5%) AHCR and one (2.5%) HHCR socket. In conclusion, while a routine high hip center should not be recommended, cup placement at a center of rotation height < 20 mm is associated with higher rates and magnitudes of anterior cup protrusion in severe dysplasia.

Single-taper conical tapered stem in total hip arthroplasty for developmental dysplasia of the hip: A long-term evaluation.

INTRODUCTION: Conical tapered stems may be useful implants to manage the reconstruction of complex dysplastic anatomies. The aims of this paper were to assess: 1) the preoperative CT features of the dysplastic femurs; 2) survival rates, complications and reasons for revision; 3) the clinical outcomes; 4) the radiographic outcomes of single-taper conical stems in dysplasia (defined as center edge angle < 20°) at a long-term follow-up. HYPOTHESIS: Monoblock conical stem provides a 10-year survival rate of at least 95%, with excellent clinical outcomes and bony ingrowth. MATERIALS AND METHODS: In total, 100 THAs in 85 patients (15 bilateral cases) were enrolled. The average age of the patients at surgery was 50.9±11.5 years. Assessment of the native femoral morphology was performed using CT-scan, coronal (neck-shaft angle, offset, center of rotation position) and axial parameters (anteversion, mediolateral and anteroposterior femoral diameters). Clinical (HHS score) and radiological (osseointegration, subsidence and offset reconstruction) outcomes were evaluated at the last available follow-up. RESULTS: The mean follow-up was 9.34±5.61 years. Severely distorted anatomies from Crowe I to Crowe IV were included, with a mean canal flare of 4.3 and a mean femoral antetorsion of 34°. The survival rates were stable at long-term (98.9% at 10 and 15 years): no aseptic loosening occurred. The mean postoperative HHS was 89.8±6.8 points. Ninety-nine percent of the stems showed bone ingrowth, from 6 months to the last available follow-up. Subsidence occurred in 18% of the cases (mean value: 2.5mm, range: 1-6mm) in the first month, with subsequent stabilization. A mild proximal stress shielding occurred in 28% of the THAs. Radiolucent lines were detected in the 8% of the cases. There was a postoperative loss of offset in 12% of the cases. DISCUSSION: Conical stems in dysplastic hips achieved bony ingrowth at long-term outcome, even in complex anatomies. Subsidence, proximal stress shielding and imperfect offset restoration may occur with this implant. LEVEL OF PROOF: IV; retrospective study.

Titanium modular stems in total hip arthroplasty due to developmental dysplasia: a registry comparison with single-taper implants.

INTRODUCTION: The routine use of proximal femoral modularity was discouraged in total hip arthroplasties (THAs). However, titanium dual-taper (DT) implants may provide some advantages over single-taper (ST) stems in cases of complex deformity. A registry study comparing ST and DT stems in dysplasia was designed, aiming to assess: (1) survival rates at long-term; (2) reasons for revision; (3) the profile of failed implants. METHODS: The arthroplasty registry RIPO was investigated for cementless THAs performed for dysplasia since 2000. ST implants were compared to titanium-on-titanium DT stems. Demographics and implant features were collected. Survival rates and reasons for revision were compared. The profile of DT stem failures in dysplasia was defined. RESULTS: 6429 implants were included in the study, 3642 ST and 2787 DT. The demographic and implant features of the 2 cohorts were not comparable. The DT cohort achieved higher survival rates at long-term (93.9% vs. 91.6%, p = 0.018). DT implants showed a higher rate of implant breakage (0.6%, p = 0.011) and a lower rate of aseptic loosening (p = 0.005). There were no differences in terms of revisions for dislocation. No metallosis occurred. There were more revisions in DT implants in males <65 years, with a 28-mm head size or smaller. CONCLUSIONS: Modularity did not result in lower survival rates in dysplastic patients and may even reduce the rate of aseptic loosening in comparison to ST stems. The rate of implant breakage is not negligible. Younger males are not good candidates for titanium DT stems.

One-stage complete eradication and revision hip due to pseudotumor in metal-on-metal hip arthroplasty.

Background: The correct management and treatment of pseudotumors due to metal-on-metal (MOM) hip arthroplasty are still debated. The purpose of this study is to analyze the surgical treatment and the clinical and radiographic 3-year outcomes of MOM arthroplasty revisions due to pseudotumor treated with a strategy of excision and revision. Methods: Consecutive, retrospective series of 21 patients (8 males/13 females) with pseudotumor due to MOM hip arthroplasty was surgically treated at a single tertiary center. Demographic, clinical, radiological and implant-related features were collected pre-operatively. Post-revision clinical and radiographic parameters were evaluated. Chromium (Cr) and cobalt (Co) blood samples were collected before and after surgery. Results: Three patients (14.2%) with pseudotumor underwent a resection arthroplasty due to infection (perioperative finding) and could not be reimplanted due to septic relapses. Twenty (95.2%) pseudotumors were completely resected. Revisions [2 total hip reimplantations (11.1%) and 16 isolated component revisions (88.9%)] were performed with non-MOM couplings. A clinical improvement at a mean post-revision follow-up 3.3 years [standard deviation (SD), ±2.2 years] was observed, from 50.3 (SD, ±4.6) to 88.3 (SD, ±9.2) Harris hip score (HHS) points (P<0.001). Among revisions, there were 5 complications (23.8%): 1 dislocation, 1 psoas impingement, and 3 infections (14.2%). No re-revision was carried out. Three (14.2%) pseudotumors recurred: 1 was surgically treated, 1 was treated with selective arterial embolization, and 1 clinically followed. At the final follow-up, Cr and Co blood ions beyond the threshold decreased from 85.7% cases to 0% in the seven patients that could be evaluated. Conclusions: The one-stage strategy of radical excision and revision with non-MOM couplings in pseudotumors due to MOM hip arthroplasty achieved good 3-year outcomes. However, complications were frequent (23%). Recurrences were not rare (14%) and did not require implant re-revision.

Preoperative and postoperative risk factors for periprosthetic joint infection in primary total hip arthroplasty: A 1-year experience.

BACKGROUND: Periprosthetic joint infection (PJI) in primary total hip replacement (THR) is one of the most important threats in orthopedic surgery, so one important surgeon's target is to avoid or early diagnose a PJI. Although the incidence of PJI is very low (0.69%) in our department, with an average follow-up of 595 d, this infection poses a serious threat due to the difficulties of treatment and the lower functional outcomes after healing. AIM: To study the incidence of PJI in all operations occurring in the year 2016 in our department to look for predictive signs of potential infection. METHODS: We counted 583 THR for 578 patients and observed only 4 cases of infection (0.69%) with a mean follow-up of 596 d (min 30, max 1451). We reviewed all medical records to collect the data: duration and time of the surgery, presence, type and duration of the antibiotic therapy, preoperative diagnosis, blood values before and after surgery, transfusions, presence of preoperative drugs (in particularly anticoagulants and antiaggregant, corticosteroids and immunosuppressants), presence of some comorbidities (high body mass index, blood hypertension, chronic obstructive pulmonary disease, cardiac ischemia, diabetes, rheumatological conditions, previous local infections). RESULTS: No preoperative, intraoperative, or postoperative analysis showed a higher incidence of PJI. We did not find any class with evident major odds of PJI. In our study, we did not find any border value to predict PJI and all patients had similar values in both groups (non-PJI and PJI). Only some categories, such as female patients, showed more frequency of PJI, but this difference related to sex was not statistically significant. CONCLUSION: We did not find any category with a higher risk of PJI in THR, probably due to the lack of few cases of infection.

Patient reported outcomes measures (PROMs) trajectories after elective hip arthroplasty: a latent class and growth mixture analysis.

BACKGROUND: Patient-reported outcome measures (PROMs) are an extensively used tool to assess and improve the quality of healthcare services. PROMs can be related to individual demographic and clinical characteristics in patients undergoing hip arthroplasty (HA). The aim of this study is to identify distinct subgroups of patients with unique trajectories of PROMS scores and to determine patients' features associated with these subgroups. METHODS: We conducted a prospective, cohort study in which PROMs questionnaires (Euro Quality 5 Dimensions 3L, EQ-5D-3L, Euro-Quality-Visual-Analytic-Score, EQ-VAS, Hip disability and Osteoarthritis Outcome Score, HOOS-PS) were administered to patients undergoing elective HA pre-operatively, and at 6 and 12 months after surgery. For each measure, latent class growth analysis and growth mixture models were used to identify subgroups of patients with distinct trajectories of scores. Demografic and clinical predictors of the latent classes in growth mixture model were identified using a 3-step approach. RESULTS: We found three distinct trajectories for each PROM score. These trajectories indicated a response heterogeneity to the HA among the patients (n = 991). Patient's gender, ASA score, and obesity were significantly associated with different PROMs trajectories. CONCLUSIONS: We identified three distinct trajectories for each of the three PROMs indicators. Several demographic and clinical characteristics are associated with the different trajectories of PROMs at 6 and 12 months after HA and could be used to identify groups of patients with different outcomes following HA surgery. These findings underline the importance of patient-centered care, supporting the usefulness of integrating PROMs data alongside routinely collected healthcare records for guiding clinical care and maximizing patients' positive outcomes. TRIAL REGISTRATION: Protocol version (1.0) and trial registration data are available on the platform www. CLINICALTRIAL: gov with the identifier NCT03790267, posted on December 31, 2018.

Which stem in total hip arthroplasty for developmental hip dysplasia? A comparative study using a 3D CT-based software for pre-operative surgical planning.

BACKGROUND: Stem choice in total hip arthroplasty (THA) for hip dysplasia is still controversial. The aims of the study were to evaluate (1) which stem design provided the highest percentage of adequate reconstructions in THA for dysplasia and (2) any correlation between the reconstructions provided by the stems and the native femoral morphology. MATERIALS AND METHODS: 150 CT scans including 200 adult dysplastic hips were randomly selected. Using the 3D CT-based software Hip-Op for surgical planning, the native hip anatomy was studied. Then, a single wedge tapered stem, an anatomical stem and a conical tapered stem were simulated in every hip. An adequate reconstruction of hip biomechanics was obtained when combined anteversion, offset restoration, coronal and sagittal tilt, canal filling and leg lengthening were inside the normal ranges. RESULTS: Conical stems achieved the highest percentage of adequate reconstructions (87%, p < 0.0001). The anatomical stem was the worst performer. Single wedge and anatomical stem acceptability was mainly influenced by the combined anteversion. Stem anteversion was correlated with the femoral anteversion (fair correlation), the calcar femorale (fair) and the mediolateral femoral diameter at isthmus (poor). When the femoral anteversion was ≥ 25°, combined anteversion was very acceptable for the conical stem (99.2%), whereas the rate of acceptable combined anteversion for the single wedge tapered stem was 71.4%, and that for the anatomical stem was 51.6% (p < 0.0001). CONCLUSIONS: Stem choice in developmental hip dysplasia is mainly driven by appropriate combined anteversion, which is dependent on the coronal and axial femoral morphologies. As a rule of thumb, tapered stems are adequate when femoral anteversion is < 25°; conical stems should be adopted for higher anteversions. LEVEL OF EVIDENCE: IV.