Efficacy of an Antibiotic Loaded Ceramic-Based Bone Graft Substitute for the Treatment of Infected Non-Unions.

The treatment of non-unions is often complicated by segmental bone defects and bacterial colonization. Because of the limited availability of autologous bone grafts, tissue engineering focuses on antibiotic-loaded bone graft substitutes. HACaS+G is a resorbable calcium sulphate-hydroxyapatite loaded with gentamicin.

Pulsatile lavage systems and their potential to penetrate soft tissue.

Background: In orthopedic and trauma surgery, pulsatile lavage systems are used to clean soft tissue. This may be necessary in septic surgeries or in case of contaminated wounds after trauma. Positive features such as reduction of bacterial contamination and removal of foreign particles are counterbalanced by negative aspects such as bacterial seeding in deeper tissue layers, damage to various tissues and even cases of air embolism.

Does Kinematic Alignment Increase Polyethylene Wear Compared With Mechanically Aligned Components? A Wear Simulation Study.

Background: Kinematic alignment is an alternative approach to mechanical alignment. Kinematic alignment can restore the joint line to its prearthritic condition, and its advocates have suggested it may be associated with other benefits. But this alignment approach often results in tibial components that are placed in varus and femoral components that are placed in valgus alignment, which may result in an increased risk of component loosening because of wear.

Insights into Imprinting: How Is the Phenomenon of Tribocorrosion at Head-Neck Taper Interfaces Related to Corrosion, Fretting, and Implant Design Parameters?

Background: Wear and corrosion at modular neck tapers in THA can lead to major clinical implications such as periprosthetic osteolysis, adverse local tissue reactions, or implant failure. The material degradation processes at the taper interface are complex and involve fretting corrosion, third-body abrasion, as well as electrochemical and crevice corrosion. One phenomenon in this context is imprinting of the head taper, where the initially smooth surface develops a topography that reflects the rougher neck taper profile.

Effect of surface topography and residual stress on the taper connection stability in total hip arthroplasty.

In the present work, the influence of the trunnion surface topography and the near-surface residual stresses on the joining process of a taper connection is examined using a replicate of the realistic taper connection as it occurs in conventional hip joint implants. The focus of the work is on the surface of the taper trunnion made of Ti6Al4V ELI and its effect on the connection stability with a CoCrMo counterpart. In this regard, the interrelation between surface topography, residual stresses, the joining behavior and the corrosion behavior under dynamic loading have been systematically investigated.

Wear investigation based on a novel, anatomic shoulder prosthesis with bearing materials inversion.

Introduction: In shoulder arthroplasty, ultra-high-molecular-weight polyethylene is used as standard material for glenoid components. The emergence of wear particles and their influence on the aseptic loosening of joint replacements are well known. The aim of the present study is to investigate the wear behaviour of the implant combinations as well as the size and morphology of the released wear particles from novel anatomic shoulder prosthesis.

EFORT recommendations for off-label use, mix & match and mismatch in hip and knee arthroplasty.

Off-label use is frequently practiced in primary and revision arthroplasty, as there may be indications for the application of implants for purposes outside the one the manufacturers intended.Under certain circumstances, patients may benefit from selective application of mix & match. This can refer to primary hip arthroplasty (if evidence suggests that the combination of devices from different manufacturers has superior results) and revision hip or knee arthroplasty (when the exchange of one component only is necessary and the invasiveness of surgery can be reduced).

Cement debonding behaviors of the various tibial components of the ATTUNE knee system and its predecessors: Is a cement-in-cement revision an alternative?

Background: Aseptic loosening remains one of the most common causes of revision of the tibial component for total knee arthroplasty. A stable bond between implant and cement is essential for appropriate long-term results. The aim of our in vitro study was to investigate the maximum failure load of tibial ATTUNE prosthesis design alternatives compared with a previous design.

Primary Stability in Hip Revision Arthroplasty: Comparison of the Stability of Cementless Fixed Augments on a Modular Acetabular Cage System with and without Cranial Straps.

The goal of this study is to evaluate the primary stability of a cementless augment-and-modular-cage system with and without the addition of cranial straps in a standardized in vitro setting. As the surrogate parameter for the evaluation of primary stability, the measurement of relative motion between the implant components themselves and the bone will be used. Acetabular revision components with a trabecular titanium augment in combination with a large fourth-generation composite left hemipelvis were assembled.

The Expression Levels of Toll-like Receptors after Metallic Particle and Ion Exposition in the Synovium of a Murine Model.

To date, the exact role of specific Toll-like receptors (TLRs) in regulating immune reactivity to metallic byproducts of orthopedic implants has not been fully clarified. In light of the situation, our objective in this investigation was to assess the expression levels of surface TLRs after metallic particle and ion exposure in an established animal model. Ten female BALB/c mice in each group received intra-articular injections of phosphate buffer (PBS) (control), metallic particles (MP), and metallic ions (MI), respectively.

[Typing and particle analysis of squeaking hip endoprostheses : First histopathological analysis to examine the squeaking pathogenesis of ceramic-on-ceramic bearings].

Background: Since the use of ceramic-on-ceramic (CoC) hip endoprostheses complications in the form of squeaking noises have occasionally occurred.

Objectives: This is the first histopathological analysis of the synovia-like interface membrane (SLIM) of ceramic squeaking hip endoprostheses with the aim to gain new insights into the squeaking pathogenesis.

Materials And Methods: Seven CoC hip endoprostheses with squeaking pathogenesis are analyzed by SLIM consensus classification, particle algorithm, CD3 quantification, semiquantitative CD68 macrophages, Oil-Red positive macrophages, hemosiderin evaluation and in two cases by energy dispersive X‑ray spectroscopy (EDX).

Amorphous Carbon Coatings for Total Knee Replacements-Part II: Tribological Behavior.

Diamond-like carbon coatings may decrease implant wear, therefore, they are helping to reduce aseptic loosening and increase service life of total knee arthroplasties (TKAs). This two-part study addresses the development of such coatings for ultrahigh molecular weight polyethylene (UHMWPE) tibial inlays as well as cobalt-chromium-molybdenum (CoCr) and titanium (Ti64) alloy femoral components. While the deposition of a pure (a-C:H) and tungsten-doped hydrogen-containing amorphous carbon coating (a-C:H:W) as well as the detailed characterization of mechanical and adhesion properties were the subject of Part I, the tribological behavior is studied in Part II.

Early tibial loosening of the cemented ATTUNE knee arthroplasty - Just a question of design?

Background: Total knee arthroplasty is a very successful standard treatment for severe osteoarthritis. Nevertheless, the literature reports tibial debonding between implant and bone cement as well as radiolucent lines related to the tibial components of different knee systems. Regardless of cementing techniques and the influences during surgery, we examined the design of a newly developed knee system and its predecessors (Attune, Attune S+, P.

Special Issue "Novel Research about Biomechanics and Biomaterials Used in Hip, Knee and Related Joints".

Joint replacement is a very successful medical treatment [...

The effect of surgical suture material on osteoclast generation and implant-loosening.

Implant loosening - either infectious or aseptic- is a still a major complication in the field of orthopaedic surgery. In both cases, a pro-inflammatory peri-prosthetic environment is generated by the immune system - either triggered by bacteria or by implant wear particles - which leads to osteoclast differentiation and osteolysis. Since infectious cases in particular often require multiple revision surgeries, we wondered whether commonly used surgical suture material may also activate the immune system and thus contribute to loss of bone substance by generation of osteoclasts.

Bacterial Biofilm Components Induce an Enhanced Inflammatory Response Against Metal Wear Particles.

Purpose: Aseptic implant loosening is still a feared complication in the field of orthopaedics. Presumably, a chronic inflammatory response is induced by wear particles, which leads to osteoclast generation, bone degradation and hence loosening of the implant. Since it has been demonstrated in the literature that most implants are in fact colonized by bacteria, the question arises whether aseptic implant loosening is truly aseptic.

Wear and damage in retrieved humeral inlays of reverse total shoulder arthroplasty-where, how much, and why?

Background: Polyethylene (PE) wear and material degradation have been reported as complications in reverse total shoulder replacements (rTSAs). In this regard, scapular notching is associated with more clinical complications. Therefore, the purposes of the study were to quantify the linear and volumetric wear, as a measure for the amount of removed material, and to qualitatively assess the PE damage modes to describe the material degradation in retrieved rTSA humeral PE inlays that contribute to failure of shoulder replacements.

Short-Term Heat Treatment of Ti6Al4V ELI as Implant Material.

Due to its mechanical properties and good biocompatibility, Ti6Al4V ELI (extra low interstitials) is widely used in medical technology, especially as material for implants. The specific microstructures that are approved for this purpose are listed in the standard ISO 20160:2006. Inductive short-term heat treatment is suitable for the adjustment of near-surface component properties such as residual stress conditions.

Bearing Thickness Is Not a Predictive Factor for Damage and Penetration in Oxford Unicompartmental Knee Arthroplasty-A Retrieval Analysis.

The medial Oxford unicompartmental knee arthroplasty (OUKA) shows good survivorship, as well as clinical results. Aseptic loosening, however, remains one of the main reasons for revision and polyethylene debris is known to cause aseptic loosening. The role of bearing thickness in total as well as unicondylar knee arthroplasty has been the subject of controversial discussions, especially the longevity of lower thickness bearings in total knee arthroplasty was questioned.

IgY Targeting Bacterial Quorum-Sensing Molecules in Implant-Associated Infections.

: Implant-associated infections are still a major complication in the field of orthopedics. Bacteria can form biofilms on implant surfaces, making them more difficult to detect and treat. Since standard antibiotic therapy is often impaired in biofilm infections, particular interest is directed towards finding treatment alternatives.

Effect of bone quality and quantity on the primary stability of dental implants in a simulated bicortical placement.

Objectives: Conventional dental implants inserted in the molar region of the maxilla will reach into the sinus maxillaris when alveolar ridge height is limited. When surgery is performed without prior augmentation of the sinus floor, primary stability of the implant is important for successful osseointegration. This study aimed at identifying the impact of bone quality and quantity at the implantation site on primary implant stability of a simulated bicortical placement.

The Migration Pattern of a Cementless Hydroxyapatite-Coated Titanium Stem under Immediate Full Weight-Bearing-A Randomized Controlled Trial Using Model-Based RSA.

(1) Background: High primary stability is important for the long-term survival of cementless femoral stems in total hip arthroplasty (THA). The objective of this study was to investigate the migration pattern of a hydroxyapatite-coated cementless hip stem developed for minimally invasive surgery using model-based radiostereometric analysis (RSA). (2) Methods: In this randomized controlled trial, 44 patients with an indication for cementless primary THA were randomly allocated to receive either the SL-PLUS MIA stem, developed for minimally invasive surgery, or the SL-PLUS stem (Smith & Nephew Orthopaedics, Baar, Switzerland) which served as a control group.

Biological Reactions to Metal Particles and Ions in the Synovial Layer of Mice.

Metal particles and ions released from implants not only have a fundamental effect on the longevity of total joint replacements, but can also be disseminated to remote organs. Periprosthetic tissues harvested during revision surgeries mainly reflect end-stage failure but may not adequately reveal initial biological reactions and systemic side effects. Therefore, primary reactions caused by metal particles and ions were investigated in an established murine model.

Blood Metal Ion Release After Primary Total Knee Arthroplasty: A Prospective Study.

Objectives: To investigate the course of in vivo blood metal ion levels in patients undergoing primary total knee arthroplasty (TKA) and to investigate potential risk factors associated with metal ion release in these patients.

Methods: Twenty-five patients with indication for TKA were included in this prospective study. Whole blood metal ion analysis was performed pre-operatively and at 1 week, 6 weeks, 3 months, 6 months, and 12 months postoperatively.

Long-Term Results of a Second-Generation, Small-Diameter, Metal-On-Metal Bearing in Primary Total Hip Arthroplasty at 14-year Follow-Up.

(1) Background: The objective of the present study was to review the clinical and radiological results of a small-head, MoM bearing in primary THA and to determine blood metal ion levels at long-term follow-up. (2) Methods: We retrospectively evaluated the clinical and radiological results of 284 small-diameter, MoM 28-mm Metasul THA at a mean follow-up of 14.5 years, and measured blood metal ion concentrations in 174 of these patients.