Trabecular titanium cups in acetabular revision arthroplasty: analysis of 10-year survivorship, restoration of center of rotation and osteointegration.

AIMS: In case of severe bone loss, acetabular revision can be challenged using extra porous pure trabecular titanium (TT) revision cups designed to ensure enhanced iliac and ischiatic purchase. Aim of the study is to report on the clinical and radiological results of a TT acetabular component, evaluating functional outcome, restoration of the hip center of rotation and osteointegration. METHODS: 85 patients, who underwent acetabular revision with a TT revision cup system between October 2009 and December 2018, were included in a retrospective study. Clinical outcome were assessed with Harris Hip Score (HHS). The hip rotation center was measured using the Pierchon method on the AP pelvis film. Loosening of the cup was determined according to the Kosashvili modification of Gill's criteria. Kaplan- Meier survivorship curve was performed. Results The mean follow-up was 6.12 years. The average HHS improved from 54.7 points to 89.7 points (p < 0.05). Two acetabular components (2.3%) were re-revised after a mean of 5.6 years, for aseptic loosening and for infection, with a progressive radiolucency and a > 5 mm vertical migration, respectively. The radiographic evaluation of the position of the hip rotation center revealed a statistically significant difference (p < 0.05) between the pre- and post-operative values. The hip rotation center was correctly restored within 5% of the reference Pierchon values in a percentage of 85.4% relative to horizontal parameters and within 8% in a percentage of 66.7% relative to vertical parameters. 5-year and 10-year survivorships were, respectively, 100% and 88%. CONCLUSIONS: In case of severe bone loss, TT revision cup system allows for good restoration of center of rotation and osteointegration showing good 10-year survival rate.

Clinical characteristics and laboratory biomarkers changes in COVID-19 patients requiring or not intensive or sub-intensive care: a comparative study.

BACKGROUND: Identifying risk factors for severe novel-coronavirus disease (COVID-19) is useful to ascertain which patients may benefit from advanced supportive care. The study offers a description of COVID-19 patients, admitted to a general ward for a non-critical clinical picture, with the aim to analyse the differences between those transferred to the intensive (ICU) and/or sub-intensive care (SICU) units and those who were not. METHODS: This observational retrospective study includes all COVID-19 patients admitted to the Infectious Diseases Unit. Clinical, laboratory, radiological and treatment data were collected. The primary outcome was a composite of need of transfer to the ICU and/or SICU during the hospitalization. Patients who did not require to be transferred are defined as Group 1; patients who were transferred to the ICU and/or SICU are defined as Group 2. Demographic, clinical characteristics and laboratory findings at the 1st, 3rd and last measurements were compared between the two groups. RESULTS: 303 were included. The median age was 62 years. 69 patients (22.8%) met the primary outcome and were defined as Group 2. The overall fatality rate was 6.8%. Group 2 patients were predominantly male (76.8% vs. 55.1%, p < 0.01), had a higher fatality rate (14.5% vs. 3.8%, p < 0,01), had more hypertension (72.4% vs. 44%, p < 0,01) and diabetes (31.9% vs. 21%, p = 0.04) and were more likely to present dry cough (49.3% vs. 25.2%, p < 0.01). Overall, chest X-ray at admission showed findings suggestive of pneumonia in 63.2%, and Group 2 were more likely to develop pathological findings during the hospitalization (72.7% vs. 17.2%, p = 0.01). At admission, Group 2 presented significantly higher neutrophil count, aspartate-transaminase and C-Reactive-Protein. At the 3rd measurement, Group 2 presented persistently higher neutrophil count, hepatic inflammation markers and C-Reactive-Protein. Group 1 presented a shorter duration from admission to negativization of follow-up swabs (20 vs. 35 days, p < 0.01). CONCLUSIONS: The presence of comorbidities and the persistent observation of abnormal laboratory findings should be regarded as predisposing factors for clinical worsening.

Patients Following Revision Total Hip Arthroplasty With Modular Dual Mobility Components and Cobalt-Chromium Inner Metal Head are at Risk of Increased Serum Metal Ion Levels.

BACKGROUND: Modular dual-mobility (MDM) total hip arthroplasty (THA) is designed with a cobalt-chromium liner inserted into a titanium acetabular component. The purpose of this study is to investigate the potential risks for fretting corrosion at this junction, by measuring serum metal ions, after MDM acetabular revision. METHODS: Thirty-seven patients with well-functioning revision THAs participated in a cross-sectional study at mean 5.1 (2-10) years after surgery. All received a trabecular titanium MDM acetabular component. The serum levels of cobalt and chromium were measured using mass spectrometry. RESULTS: The mean values of chromium and cobalt were 2.08 µg/L (95% confidence interval 0.9-3.2, range 0.02-11.8) and 1.99 µg/L (95% confidence interval 0.81-3.17, range 0.07-16.05), respectively. Eleven patients (29, 7%) had ion levels above the normal range, with 6 (16.2%) above 5 µg/L and 5 (13.5%) between 1 and 5 µg/L. A significant correlation was found between an elevated serum metal ion level and University of California Los Angeles score (P = .016). CONCLUSION: We conclude that serum metal level elevation may occur secondary to metal debris resulting from corrosion of the index MDM THA. This potential risk should be included in the decision-making process when dealing with revision arthroplasty in young and active patients.

The anterior-based muscle-sparing approach to the hip: the "other" anterior approach to the hip.

PURPOSE: The purpose of this study was to evaluate safety, efficacy, and learning curves of anterior-based muscle-sparing total hip arthroplasty (ABMS-THA) in the supine position. Furthermore, early functional outcome was evaluated and compared to direct anterior approach (DAA) by measuring surface electromyography (sEMG). METHODS: We present a prospective cohort study of 343 hips. The safety and learning curve were assessed by recording operative time and peri-operative adverse events. For assessment of efficacy, functional and radiological outcomes were evaluated. A selected group of 32 patients have been studied by sEMG and compared to a matched group of 32 patients who received a THA using DAA approach. RESULTS: There was one dislocation (0.3%); two (0.6%) patients had an intra-operative fractures of the greater trochanter; two patients (0.6%) experienced a self-limited femoral nerve palsy. Physical therapy milestones for hospital discharge were reached on an average of 1.7 days. sEMG showed that ABMS and DAA have a similar muscle recruitment pattern and functional recovery after THA. One patient was revised for infection, 16 were lost, and 326 hips were available with a median follow-up of 42 months (range 24-60). The mean Harris Hip Score (HSS) increased from 44.3 to 91.9. Ninety-six percent of the hips had a leg length discrepancy (LLD) < 5 mm. There were no radiological signs of mechanical loosening or osteolysis. CONCLUSIONS: The ABMS approach in the supine position is clinically effective and safe; special advantages include a very low dislocation rate and a great control of LLD.

A novel technique to preserve range of motion in two-stage revision of infected total knee arthroplasty.

PURPOSE: Two-stage revision represents the gold standard in the treatment of infected total knee arthroplasty. Different techniques have been proposed, mostly not preserving range of motion. An articulated antibiotic-loaded cement spacer made in association with two unicompartmental implants has been used as an alternative to a static spacer in an effort to retain as much movement as possible between the stages in young, high-demand patients with preserved ROM. METHODS: We evaluated nine consecutive patients with a mean age of 66.5 years. The second stage was performed after lab tests returned to normal and culture proved negative. Mean follow-up was 4.6 years. RESULTS: Mean ROM from a preoperative value of 105.6° was 103.5° after the first stage, and improved to 110.0° after the definitive implant. Mean Knee Society score was 27.6 preoperatively improving to 86.4 points postoperatively. WOMAC score showed that six patients were very satisfied with the overall result of their reimplanted knee, three subjects were somewhat satisfied. No recurrence of infection, no significant radiolucent lines or osteolysis were recorded at clinical and radiological follow-up and the patients were satisfied with the outcome. CONCLUSIONS: Results indicated that this technique may ensure the advantages of a static spacer, but allow a greater ROM and better functional recovery. It may be considered as a viable option in selected cases even though the higher costs of two unicompartmental implants should be considered in the light of other aspects, such as prolonged hospital stay and rehabilitation in revision of infected total knee arthroplasty.

The lesser trochanter "Sling fixation technique" in proximal intramedullary nailing of unstable intertrochanteric fractures: A polymer-based cerclage wiring.

Introduction: Lesser trochanter (LT) fixation to restore the continuity of the posteromedial fragment using a cerclage wire has been reported to provide a more stable reduction in the treatment of unstable femoral neck fractures with LT involvement. However, LT fixation is not commonly performed due to the complications associated with the traditional monofilament cerclage metal wires. In this study, we investigate the clinical and radiological outcomes of a new technique for LT fixation in conjunction with Intramedullary (IM) fixation with nail and screws when compared to isolated IM fixation. The Sling Fixation Technique involves a new wiring technique and the use of a polymer-based cerclage cable characterized by iso-elastic properties that is hypothesized to provide better clinical and radiographic outcomes. Patients and methods: This prospective observational study included 30 patients who underwent proximal IM nailing from July 2019 to April 2020. Thirty consecutive patients (30) were assigned to 2 different treatment groups. Fifteen (15) patients were treated with the IM Nailing and Sling Fixation Technique and 15 with IM nailing only. Patients were comparable for demographic features, fracture pattern, age, gender and associated medical comorbidities. Clinical outcomes were analyzed in terms of time needed to achieve complete weight bearing, Harris hip score (HHS), Barthel Index (BI) and Radiographic Union Scale for Hip (RUSH). The follow-up period was one year. Results: Time for fracture healing and to achieve weight-bearing in the "Sling" group were shown to be significantly shorter than in the IM group. The Sling group showed furthermore better HHS, BI and RUSH scores when compared to the IM group at 1, 3, 6, and 12 months from the surgery. No complications such as wiring breakage, cut-outs, breakage or pullout of the fixation screws were observed; one case of heterotrophic ossification was reported. Conclusion: In cases of unstable intertrochanteric fractures of the proximal femur with lesser trochanter involvement, the Sling fixation technique using an isoelastic polymer-based wire showed superior results in terms of stability and consequently better clinical and radiographic outcomes than IM nailing only.

The 5-year results of an oxidized zirconium femoral component for TKA.

UNLABELLED: Osteolysis secondary to polyethylene wear is one of the major factors limiting long-term performance of TKA. Oxidized zirconium is a new material that combines the strength of a metal with the wear properties of a ceramic. It remains unknown whether implants with a zirconium femoral component can be used safely in TKA. To answer that question, we reviewed, at a minimum of 5 years, the clinical outcome and survivorship of a ceramic-surfaced oxidized zirconium femoral component implanted during 98 primary TKAs between April 2001 and December 2003. Survivorship was 98.7% at 7 years postoperatively. No revision was necessary and only one component failed because of aseptic loosening. Mean Knee Society score improved from 36 to 89. No adverse events were observed clinically or radiologically. These results justify pursuing the use of oxidized zirconium as an alternative bearing surface for a femoral component in TKA. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Surgical prosthetic treatment.

Fragility fractures typically occur in elderly patients related principally to osteoporosis. A significative percentage of these fractures have to be treated surgically but comorbilities are often present, and need to be grossly stabilized before surgery. However, there is for these fractures a high rate of morbidity and mortality at short-term. Moreover, patients affected by a fragility fracture are at risk for another fragility fracture later in life.The Authors present an overview of the main patterns of proximal femoral fractures, underlining the peculiar features and choices of surgical treatment, and relating to specific indications and results of each treatment.

"Anterolateral" approach to the hip: a systematic review of the correct definition of terms.

PURPOSE: The Watson-Jones interval plane between tensor fascia lata (TFL) and the gluteus medius (GM) has come back into fashion in the past few years - Röttinger described the anterolateral minimal invasive approach (ALMI) for use in total hip replacement, in which the standard Watson-Jones interval was used, but with a completely intermuscular plane. However, the term anterolateral is often still utilised to describe intramuscular approaches in which the GM was violated, thus creating a potential misunderstanding in the literature. Accordingly, we have designed a study to answer the following questions: (1) are there articles in the recent literature that use the term "anterolateral" to describe different approaches; (2) which would be the correct description of the anterolateral approach? METHODS: We did a systematic review of the literature based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, to look for peer reviewed papers of any evidence level focusing on the definition of anterolateral approach; MEDLINE and EMBASE were searched. RESULTS: 73 manuscripts met the criteria of the systematic search. 53 papers (72.6%) reported the term anterolateral approach to describe a complete intermuscular approach between the interval between GM and TFL. Nonetheless, in the remaining 20 papers (27.4%) the term anterolateral was used to describe intramuscular approaches in which the gluteus medius was violated. CONCLUSION: In about 1 out of 4 papers in the recent literature, the term anterolateral was utilised to describe approaches that are completely different both in terms of anatomy and function.

Precision and accuracy of robot-assisted technology with simplified express femoral workflow in measuring leg length and offset in total hip arthroplasty.

BACKGROUND: Semi-active robot-assisted total hip arthroplasty (THA) has two options to measure the leg length discrepancy (LLD) and combined offset (CO), the 'enhanced' femoral workflow and the so-called 'express' simplified workflow. The purpose of this study was to determine the precision and accuracy of intraoperative LLD and CO measurement with express workflow robotic THA. METHODS: Between February 2018 and December 2019, 30 patients underwent an express workflow robot-assisted primary THA for intraoperative LLD and CO measurements. Postoperative radiographs were used for LLD and CO measurement. In order to examine the accuracy of the robotic system assessment, the absolute difference between the robotic assessments and radiographic evaluations was calculated. RESULTS: Intraoperative robotic measurements reported a mean error of 0.2-0.6 mm for each registration, with no significant difference between them (p = 0.311). The average absolute discrepancies between the robotic and radiographic assessments in the LLD and CO measurements were 1.3 ± 1.5 mm (p = 0.17) and 1.1 ± 0.9 mm (p = 0.11), respectively, while the Pearson's correlation coefficients were 0.69 and 0.71. CONCLUSIONS: An external marker without a femoral array inserted into a screw positioned in the greater trochanter would be an easier and faster method to measure LLD and CO. Our study showed that the measured values of LLD and CO obtained by intraoperative express workflow robot-assisted THA system were precise and accurate.

Accelerometer-Based Navigation in Total Knee Arthroplasty for the Management of Extra-Articular Deformity and Retained Femoral Hardware: Analysis of Component Alignment.

Purpose Recent advances in total knee arthroplasty (TKA) include an accelerometer portable system designed to improve component position and alignment. The purpose of this study is to evaluate whether accelerometer navigation system can be a valuable option in complex TKAs for extra-articular deformity of the lower limb or in case of retained femoral hardware. Methods A group of 13 patients underwent TKA with an accelerometer navigation system. Three patients had a tibial extra-articular deformity, six had a femoral extra-articular deformity, and four had an intramedullary nail in the femur. Preoperative and postoperative mechanical axes were measured from full-length lower extremity radiographs to evaluate alignment. The alignment of prosthetic components in the frontal and sagittal planes was determined by postoperative radiographs. Results At 30-days postoperative radiographic check, the hip knee ankle angle was within 2.0° (0 ± 1) of the neutral mechanical axis. The alignment of the tibial component on the frontal plane was 90.0° (range 89-91) and on the sagittal plane 5.0° (range 3-7). The alignment of the femoral component on the frontal plane was 90.0° (range 89-91) and on the sagittal plane 3.0° (range 0-5). Conclusion The alignment of the prosthetic components has been accurate and comparable to other navigation systems in literature without any increase in surgical times. The accelerometer-based navigation system is therefore a useful technique that can be used to optimize TKA alignment in patients with extra-articular deformity or with lower limb hardware, where the intramedullary guides cannot be applied. Level of Evidence This is an observational study without a control group, Level III.

Joint line position in revision total knee arthroplasty: the role of posterior femoral off-set stems.

BACKGROUND: Elevation of the joint line frequently occurs in revision total knee arthroplasty (RTKA) because of a wider flexion space than extension space. One solution to balance this flexion-extension space involves the introduction of couplers between the stem and femoral components, and the use of posteriorly offset femoral stems that we hypothesized would improve gap balancing and facilitate joint line restoration. METHODS: We retrospectively reviewed a selected series of 43 RTKA. Postoperative joint line height was subtracted from intended height using postoperative lateral radiographs. The value was negative if the joint line position was lowered, and positive if raised. RESULTS: Forty knees were followed for a mean of 3.5years. Mean postoperative joint line position change from intended position was 1.5mm (range -2.5-7.5mm). In 28 knees (70%), the joint line position was restored to within ±2mm of the intended position; in eight knees (20%), from 2-4mm; and in four knees (10%), >4mm. Joint line position was raised in 32 knees (80%) and lowered in eight (20%). In the offset stem knees, the intended joint line position was 0.9mm (range -1.2-3.4mm) as compared with 3.2mm (range -2.5-7.5mm) for the straight stem knees. CONCLUSIONS: A coupler system between the femoral stem and femoral component restored the joint line in 70% of cases. The posterior offset stem provided increased posterior condylar offset, addressed the wider flexion space, provided better positioning of the stem, and restored the joint line. LEVEL OF EVIDENCE: Therapeutic Study Level IV.

The use of anti-osteoporosis drugs in total knee arthroplasty.

Stress shielding, osteolysis, lack of integration affect the clinical results of total joint arthroplasty. Drugs as bisphosphonates administered after surgery may improve the fixation of the components to the bone, preserving the survival of the implant: however, few reports regarding applications in Total Knee Arthroplasty (TKA) are published.

Painful knee arthroplasty: definition and overview.

Total Knee Arthroplasty (TKA) is one of the most successful procedures in Orthopaedic Surgery, with good clinical results and high survival rate in more than 90% of the cases at long-term follow-up. Since the increase of population's mean age, worsening of articular degenerative alterations, and articular sequelae related to previous fractures, there is a persistent growing of the number of knee arthroplasties in every country each year, with expected increase of complications rates. Painful TKA is considered an unusual complication, but several reports focus on this challenging clinical issue.Common causes of painful TKA may be divided as early or late, and in referred, periarticular or intra-articular. Among the early, we recall implant instability (related to surgical and technical mistakes) and problems of extensor mechanism (patella not resurfaced, malalignment of femoral, tibial, or patellar component, tendons failure or degeneration). Late causes of painful TKA are almost related to aseptic loosening and infection, but also, even if unusual, reflex sympathetic dystrophy, synovitis, and hypersensitivity to metal implants are represented.Hypersensitivity to metal is a clinical issue with significative increase, but to date without a specific characterization. The Authors report about incidence, clinical features, and diagnostic pathways of hypersensitivity to metal implants, focusing on the prevention of this challenging problem.

Painful knee prosthesis: surgical approach.

There are many conditions that may be responsible of a painful knee prosthesis. The possible causes are not always easily diagnosed. Common causes of prosthetic failure, such as aseptic loosening, infection, instability, progressive patellar arthropathy and recurrent synovitis are associated with clearly defined radiographic and/or clinical evidence. Prosthetic infection should always be considered first until any other cause has been demonstrated. In the presence of an infected prosthesis we carry out a two-step revision. Aseptic loosening needs implant revision more often with increasing prosthesis stability. Varus-valgus, anteroposterior, global and patello-femoral instability are failures often due to technical errors; superstabilized or constrained implants are needed depending on the instability entity.In presence of patello-femoral pain it is necessary to evaluate the stability of the patellar component and any alterations in its motion. Patellar progressive arthropathy can often cause late-onset knee pain; in this case patella resurfacing is needed. Altered patellar tracking, may need a lateral release but in some cases is related to misalignment of the components and the revision procedure is mandatory. Nevertheless, the diagnosis and treatment of a painful knee prosthesis can be extremely difficult if there is no clear evidence of any of the most common causes of failure. Referred pain, ligament and tendon dysfunction, cutaneous neuromas, synovitis, a patellar clunk have to be diagnosed and treated.A possible aetiological understimated factor is painful knee prosthesis due to metals sensibilization, in particular to nickel. In this event the quantity of nickel in the revision prosthesis must be minimal.