Abstract:Joint arthroplasty in young, physically active patients poses a particular challenge for surgeons. Pre-arthritic changes are common in this population. The long life expectancy of younger patients, combined with high functional demands related to work and recreational activities, makes implant selection critical. A variety of implant designs and bearing materials are available to address these requirements. Depending on individual functional demands, different combinations may be chosen to minimize wear and reduce the risk of implant-related complications. In addition, evolving alignment philosophies in knee arthroplasty, patient-specific implants, and robotic-assisted techniques have shown promising results. However, beyond accurate implant positioning, the surgeon's experience and procedural volume remain key determinants of surgical success and patient satisfaction. Increasingly, patients with hip and knee arthroplasties - particularly after unicompartmental knee arthroplasty - are encouraged to maintain an active lifestyle, including participation in sports.

Background Fragility fractures of the pelvis (FFP) in elderly patients are an increasing concern due to their association with osteoporosis and the aging population. These fractures significantly affect patients’ mobility and quality of life. This study evaluates different surgical techniques in patients suffering from FFP to provide standardized recommendations for treatment strategies. In addition, we compared therapeutic concepts and their outcome between two major trauma centers in Germany. Methods We conducted a retrospective analysis of 882 patients aged over 65 years who suffered from FFP between 2003 and 2020 at a level I and level III trauma center in a german metropolis. Fractures were classified according to Rommens and Hofmann. Data collection included patient demographics, fracture type, treatment strategy, and length of hospital stay. Results FFP I fractures were predominantly treated conservatively at both centers. Significant variability was noted in the treatment of type II and III fractures, with level III trauma center having a higher surgical intervention rate for FFP II in 27.6% compared to the level I trauma center in 9.9% of the cases. The most common procedure at both hospitals was the stabilization of the posterior pelvic ring. Patients who underwent less invasive posterior-only stabilization had shorter length of hospital stay than those who received combined anterior and posterior stabilization. Conclusions The study reveals substantial differences in the treatment approaches for FFP between two major trauma centers. Less invasive surgical methods, particularly posterior-only stabilization, are associated with shorter hospital stays and potentially better outcomes for elderly patients with unstable FFP. Clinical Relevance This study underscores the importance of minimally invasive surgical techniques in managing FFP in elderly patients, highlighting their potential to reduce the length of hospital stay and improve recovery.

BackgroundConventional knee arthroplasty offers excellent long-term durability. However, when it comes to patient satisfaction, it occasionally falls short of expectations. This is where customized knee arthroplasty comes into play: by utilizing patient-specific implant designs tailored to an individual's unique anatomy, it aims to address some of the limitations associated with standard implants.AdvantageIn addition to an optimized fit, modern customized arthroplasty also enables implant positioning based on the patient's constitutional alignment, thereby taking the concept of personalization one step further. A particularly noteworthy design feature in this context is the "decoupling" of the patellofemoral and tibiofemoral joints, which helps mitigate the potential drawbacks of individualized alignment philosophies. Unlike other technologies such as robotics or navigation, customized arthroplasty relies on preoperative, image-based analysis and planning, followed by surgical execution using patient-specific instruments (PSI). This approach enables a unique combination of standardization and individualization.ProspectsDespite its theoretical advantages, customized arthroplasty must still demonstrate its clinical benefits in practice-and, in light of rising healthcare costs, justify its economic viability.

Der patellofemorale Gelenkersatz (PFG) stellt eine knochensparende Behandlungsoption für Patienten mit isolierter patellofemoraler Arthrose dar, insbesondere für junge und aktive Betroffene mit hohen funktionellen Ansprüchen. Während primär degenerative Veränderungen selten sind, werden posttraumatische Zustände, Malalignments oder Trochleadysplasien als häufigste Ursachen identifiziert. Eine präzise präoperative Diagnostik mit bildgebenden Verfahren ist unerlässlich, um Begleitpathologien wie eine Patella alta oder eine lateralisierte Tuberositas zu erkennen und ggf. durch Zusatzoperationen wie eine Tuberositasosteotomie oder Rekonstruktion des medialen patellofemoralen Ligaments (MPFL) zu adressieren. Im Vergleich zur Totalendoprothese (KTEP) bietet der PFG Vorteile wie geringere Invasivität, besseren Erhalt des Knochenstocks und eine verbesserte Beweglichkeit, jedoch ist die Revisionsrate – insbesondere aufgrund einer tibiofemoralen Anschlussarthrose – höher. Unter strenger Indikationsstellung, präziser Operationstechnik und Berücksichtigung der individuellen Anatomie kann der PFG eine wertvolle Option zur Wiederherstellung der Gelenkfunktion und Lebensqualität darstellen.

Die konventionelle Knieendoprothetik glänzt mit hervorragenden Standzeiten. Gemessen an der Patientenzufriedenheit bleibt sie jedoch bisweilen hinter den Erwartungen zurück. Hier setzt die Individualendoprothetik an, indem sie ein patientenindividuelles Implantatdesign wählt, das an die spezifische Anatomie des Patienten angepasst ist, um die nachteiligen Effekte von Standardimplantaten zu überwinden. Neben der optimierten Passform bietet die Individualendoprothetik heutzutage auch eine an das konstitutionelle Alignment des Patienten angelehnte Implantatpositionierung und führt damit den Individualisierungsgedanken weiter fort. In diesem Zusammenhang ist insbesondere die „Entkopplung“ des Patellofemoralgelenks vom Tibiofemoralgelenk ein hervorzuhebendes Designmerkmal, das mögliche Nachteile individualisierter Alignmentphilosophien in den Hintergrund treten lässt. Dabei unterscheidet sie sich von anderen Technologien wie Robotik und Navigation durch eine präoperative, bildgestützte Analyse sowie Planung und beschränkt sich dann auf die operative Exekution mittels patientenindividueller Schnittblöcke (PSI), was neben der Individualisierung auch zu mehr Standardisierung führt. Trotz ihrer theoretischen Vorteile wird die individualisierte Endoprothetik in Zukunft ihren Nutzen erst unter Beweis stellen und auch die Frage nach ihrer Finanzierbarkeit vor dem Hintergrund des zunehmenden Kostendrucks beantworten müssen.

Navigation-assisted surgical procedures in orthopedics and trauma surgery have become increasingly widespread over the last 20 years. In addition to applications in spinal surgery, they are primarily available for knee and hip endoprosthetics. On the one hand, computer-assisted procedures have been increasingly expanded with robotic assistance systems in recent years, and on the other hand, so-called handheld navigation systems have been developed, which enable specialized use directly in the operating field at lower acquisition costs. The aim of this overview is to describe current handheld systems and to present the respective technical principles and the available scientific results. Three handheld systems for TKA use, two for THA use and one system to support pedicle screw placement on the spine are presented.

Die unikondyläre tibiofemorale Endoprothetik (UKE) wird im Vergleich zur totalen Knieendoprothetik (TKE) trotz der potenziellen Vorteile immer noch vergleichsweise selten angewandt. Eine höhere Patientenzufriedenheit der UKE steht allgemein höheren Revisionsraten im Vergleich zur TKE gegenüber. Die Routine des Operateurs ist insbesondere bei der UKE für ein erfolgreiches Ergebnis von entscheidender Bedeutung. Ferner persistieren alte „Dogmen“ zu den Indikationen und Kontraindikationen. In dieser Arbeit werden die Indikationen und Kontraindikationen der UKE mit besonderer Berücksichtigung der Einflussfaktoren auf das klinische Ergebnis und Gründe für eine Revision dargestellt. Entsprechend den Literaturdaten sind fortgeschrittene Arthrosen des kontralateralen tibiofemoralen und des kontralateralen patellofemoralen Gelenkabschnitts sowie eine Instabilität der Seitenbänder und des hinteren Kreuzbandes die einzigen eindeutigen Kontraindikationen. Hingegen stellen ein erhöhter Body-Mass-Index, das Alter, die Chondrokalzinose, der vordere Knieschmerz mit patellofemoralem Knorpelschaden und auch ein defektes (insbesondere aber funktionell stabiles) vorderes Kreuzband keine eindeutige Kontraindikation dar. Allerdings sollte wie auch bei Zustand nach Umstellungsosteotomie und bei bestehenden Erkrankungen aus dem rheumatischen Formenkreis eine kritische Abwägung der Indikation erfolgen, um Fehlschläge zu vermeiden. Sportliche Aktivitäten bedürfen prinzipiell keiner Einschränkung mehr. Die Verwendung mobiler und fixer Inlays ist als äquivalent anzusehen. Das zementfreie Vorgehen mit mobilem Inlay scheint bei Übergewicht zu einer geringeren Lockerungsrate im Vergleich zur zementierten Versorgung zu führen.

Purpose To investigate the correlation between postoperative limb/component alignments and clinical/functional outcomes following medial unicondylar knee arthroplasty (mUKA). Methods Inclusion criteria included peer-reviewed English- or German-language publications assessing postoperative limb or implant alignment and clinical outcomes of mUKA. Methodological Index for Non-Randomized Studies (MINORS) was used to assess article quality. Results A total of 2767 knees from 2604 patients were evaluated. Significant correlations were observed between postoperative limb/component alignments and clinical/functional outcomes after mUKA. Inferior outcomes were associated with lower placement and excessive valgus alignment of the tibia component (> 3°). A recommended external rotation of 4°-5° was identified for the tibia component, with specific cut-off values for the femoral and tibia components. Conclusions Optimal outcomes in mUKA were associated with a varus coronal limb alignment. The tibia implant component performed well within a specific alignment range. An exact external rotation value was recommended for the tibia component, while internal rotation correlated negatively with the femoral component. Level of evidence IV (level IV retrospective case series were included).

Total knee arthroplasty are among the most frequently conducted surgeries, due to an aging society. Since hospital costs are subsequently rising, adequate preparation of patients and reimbursement becomes more and more important. Recent literature revealed anemia as a risk factor for enhanced length of stay (LOS) and complications. This study analyzed whether preoperative hemoglobin (Hb) and postoperative Hb were associated with total hospital costs and general ward costs. The study comprised 367 patients from a single high-volume hospital in Germany. Hospital costs were calculated with standardized cost accounting methods. Generalized linear models were applied to account for confounders, such as age, comorbidities, body mass index, insurance status, health-related quality of life, implant types, incision-suture-time and tranexamic acid. Preoperative anemic women had 426 Euros higher general ward costs (p < 0.01), due to increased LOS. For men, 1 g/dl less Hb loss between the preoperative value and the value before discharge reduced total costs by 292 Euros (p < 0.001) and 161 Euros fewer general ward costs (p < 0.001). Total hospital costs were reduced by 144 Euros with 1 g/dl higher Hb on day 2 postoperatively for women (p < 0.01). Preoperative anemia was associated with increased general ward costs for women and Hb loss with decreasing total hospital costs for men and women. Cost containment, especially reduced utilization of the general ward, may be feasible with the correction of anemia for women. Postoperative Hb values may be a factor for adjustments of reimbursement systems. Retrospective cohort study, III.