Purpose:The MPP (medial patella plica) has garnered increasing clinical attention due to its potential role in patellofemoral pain syndromes. While often an anatomical relic without pathological significance, inflammation or mechanical irritation of this structure can lead to plica syndrome, causing significant clinical symptoms. The purpose of this study was to analyze the current care situation regarding plica syndrome of the knee among a large number of experienced knee surgeons. Methods:An online survey targeting the current care practices for plica syndrome was conducted among members of the German Knee Society (DKG). The survey was comprised 15 questions regarding diagnostic and treatment approaches. Data were collected anonymously and analyzed using IBM SPSS Statistics Version 26.0. Results:A total of 238 surgeons participated. Most respondents (84 %) agreed that plica syndrome could cause patellofemoral pain. The typical patient profile was predominantly female (77.7 %), aged 21-30 years (57.6 %). The majority of surgeons use magnetic resonance imaging (MRI) combined with clinical examination (58.0 %) to diagnose an MPP, and 54.2 % of surgeons resected the plica upon finding significant intraoperative evidence of impact on the patellofemoral joint. Hemarthrosis and persistent pain were the most reported complications, though 83.2 % of surgeons observed a complication rate below 11 %. Conclusion:This study provides a comprehensive overview of current practices and opinions regarding plica syndrome among experienced German knee surgeons. It emphasizes the need for further research to standardize diagnostic and therapeutic approaches, aiming to optimize patient outcomes in plica-related knee pathologies.

Purpose:The objective of this study was to systematically review the existing literature related to adjuvant injection therapies among patients with cartilage defects of the knee joint who have undergone bone marrow stimulation procedures and ascertain their potential clinical benefits. Methods:Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a search was conducted on PubMed and the Cochrane Library to identify articles documenting the utilization of adjuvant injection therapies after surgery for cartilage defects, with a minimum short-term follow-up. Animal studies, uncontrolled trials, studies lacking primary surgical intervention or those including patients with osteoarthritis were excluded. Results:Twelve articles focusing on knee cartilage defects were analysed (531 patients). Platelet-rich plasma was used in eight studies, mesenchymal stromal cells in four and hyaluronic acid in one. Injection frequency and timing varied, with the most common timing being during surgery. Primary outcome measures included subjective International Knee Documentation Committee (IKDC) and Visual Analogue Scale (VAS) scores. Subjective IKDC showed significant difference in five out of nine studies and VAS in three out of eight studies, favouring injection therapy groups. Conclusion:The present review demonstrates a large heterogeneity among included studies regarding surgical interventions, injection strategies and timing as well as outcome measures. While several studies suggest a potential benefit of adjuvant therapies, findings remain inconsistent. Due to the limited quality and comparability of the evidence, no definitive recommendations can be made at this time, highlighting the need for standardized protocols and high-quality randomized controlled trials. Level of Evidence:Level IV.

Adjuvante Injektionen nach operativer Knorpeltherapie können mit einer Vielzahl an Orthobiologika durchgeführt werden. Darunter vor allem Hyaluronsäure (HA), plättchenreiches Plasma (PRP) und mesenchymale Stromazellen (MSC). Ziel dieser adjuvanten Therapien ist es, die postoperativen Ergebnisse in der Behandlung von Knorpeldefekten weiter zu verbessern und die Geweberegeneration zu fördern. HA, ein natürlicher Bestandteil der Synovialflüssigkeit, bietet durch seine stoßabsorbierenden und entzündungshemmenden Eigenschaften vielversprechende Ergebnisse, insbesondere bei gezielter molekularer Anpassung. PRP, reich an Wachstumsfaktoren, unterstützt die Heilung durch entzündungshemmende und regenerierende Effekte, wobei Variationen in der Herstellung und Anwendung entscheidend für den Therapieerfolg zu sein scheinen. MSC hingegen zeigen als zellbasierte Therapie ein großes Potenzial, obwohl regulatorische und technische Herausforderungen deren breiten Einsatz in Deutschland bisher begrenzen. Die Übersicht aktueller Studien zeigt heterogene Ergebnisse hinsichtlich der Wahl des Orthobiologikums und des Zeitpunkts der Injektionen. Während PRP und HA in Kombination mit Knochenmarkstimulationsverfahren (BMS) wie der Mikrofrakturierung bereits recht häufig untersucht wurden, fehlen nach wie vor belastbare Daten in Kombination mit modernen, zellbasierten Verfahren wie der autologen Chondrozytentransplantation (ACT). Systematische Übersichtsarbeiten und qualitativ hochwertiger randomisiert-kontrollierte Studien sind in Zukunft zwingend erforderlich, um optimale Therapieprotokolle für die Verbesserung der operativen Knorpeltherapie zu entwickeln. Erste Hinweise deuten jedoch darauf hin, dass Orthobiologika eine effektive Ergänzung darstellen können, insbesondere zur Kontrolle postoperativer Entzündungen und Förderung der Geweberegeneration.

Orthoregeneration is defined as a solution for orthopaedic conditions that harnesses the benefits of biology to improve healing, reduce pain, improve function, and, optimally, provide an environment for tissue regeneration. Options include drugs, surgical intervention, scaffolds, biologics as a product of cells, and physical and electromagnetic stimuli. The goal of regenerative medicine is to enhance the healing of tissue after musculoskeletal injuries as both isolated treatment and adjunct to surgical management, using novel therapies to improve recovery and outcomes. Various orthopaedic biologics (orthobiologics) have been investigated for the treatment of pathology involving the elbow and upper extremity, including the tendons (lateral epicondylitis, medial epicondylitis, biceps tendonitis, triceps tendonitis), articular cartilage (osteoarthritis, osteochondral lesions), and bone (fractures, nonunions, avascular necrosis, osteonecrosis). Promising and established treatment modalities include hyaluronic acid; botulinum toxin; corticosteroids; leukocyte-rich and leukocyte-poor platelet-rich plasma; autologous blood; bone marrow aspirate comprising mesenchymal stromal cells (alternatively termed medicinal signaling cells and frequently mesenchymal stem cells [MSCs]) and bone marrow aspirate concentrate; MSCs harvested from adipose and skin (dermis) sources; vascularized bone grafts; bone morphogenic protein scaffold made from osteoinductive and conductive β-tricalcium phosphate and poly-ε-caprolactone with hydrogels, human MSCs, and matrix metalloproteinases; and collagen sponge. Autologous blood preparations such as autologous blood injections and platelet-rich plasma show positive outcomes for nonresponsive tendinopathy. In addition, cellular therapies such as tissue-derived tenocyte-like cells and MSCs show a promising ability to regulate degenerative processes by modulating tissue response to inflammation and preventing continuous degradation and support tissue restoration. LEVEL OF EVIDENCE: Level V, expert opinion.

PurposeThe purpose of this study was to investigate the impact of sex on knee function, activity and quality of life following meniscus surgery using data from the German Arthroscopy Registry.MethodsThis is a retrospective cohort study with data collected between 2017 and 2022. Patient-reported outcome measures (PROMs), namely Knee Injury and Osteoarthritis Outcome Score (KOOS), EuroQol Visual Analogue Scale (EQ Scale), and Marx Activity Rating Scale (MARS), were collected preoperatively and at 6, 12 and 24 months postoperatively. Data were analysed to examine differences between male and female patients regarding PROMs, pre-existing conditions, meniscus lesion types and surgical treatments.ResultsA total of 1106 female (36.6%) and 1945 male patients (63.7%) were included. Males were significantly younger than females and had a higher body mass index. Overall, there were four times more medial meniscus lesions (MMLs) (77.5%) than lateral meniscus lesions (LMLs) (27.9%). Degenerative LMLs were more frequent in females, while traumatic LMLs were more common in males. Frequencies of traumatic and degenerative MMLs were similar among males and females. Males had higher absolute KOOS irrespective of treatment or meniscus lesion type. Meniscus repair resulted in similar improvements in Delta KOOS for both sexes, while meniscus resection exhibited higher absolute KOOS for males at each time point. Males generally had higher EQ Scale and MARS than females.ConclusionGreater improvements in knee function, activity and quality of life were observed in males. While MMLs appear to be comparable among sexes, the nature of LML differed significantly. These results may help surgeons to refine patient selection for specific treatments to improve overall clinical outcomes.Level of EvidenceLevel III.

The complex field of femoral defects in revision hip arthroplasty displays a lack of standardized, intuitive pre- and intraoperative assessment. To address this issue, the femoral defect classification (FDC) is introduced to offer a reliable, reproducible and an intuitive classification system with a clear therapeutic guideline. The FDC is based on the integrity of the main femoral segments which determine function and structural support. It focuses on the femoral neck, the metaphysis consisting of the greater and lesser trochanter, and the femoral diaphysis. The four main categories determine the location of the defect while subcategories a, b and c are being used to classify the extent of damage in each location. In total, 218 preoperative radiographs were retrospectively graded according to FDC and compared to intraoperatively encountered bone defects. To account for inter-rater and intra-rater agreement, 5 different observers evaluated 80 randomized cases at different points in time. A Cohens kappa of 0.832 ± 0.028 could be evaluated, accounting for excellent agreement between preoperative radiographs and intraoperative findings. To account for inter-rater reliability, 80 patients have been evaluated by 5 different observers. Testing for inter-rater reliability, a Fleiss Kappa of 0.688 could be evaluated falling into the good agreement range. When testing for intra-rater reliability, Cohens Kappa of each of the 5 raters has been analyzed and the mean was evaluated at 0.856 accounting for excellent agreement. The FDC is a reliable and reproducible classification system. It combines intuitive use and structured design and allows for consistent preoperative planning and intraoperative guidance. A therapeutic algorithm has been created according to current literature and expert opinion. Due to the combination of the FDC with the recently introduced Acetabular Defect Classification (ADC) a structured approach to the entire field of hip revision arthroplasty is now available.

Guideline-based surgical cartilage therapy for focal cartilage damage offers highly effective possibilities to sustainably reduce patients' complaints and to prevent or at least delay the development of early osteoarthritis. In the knee joint, it has the potential to reduce almost a quarter of the arthroses requiring joint replacement caused by cartilage damage. Biologically effective injection therapies could further improve these results. Based on the currently available literature and preclinical studies, intra- and postoperative injectables may have a positive effect of platelet-rich plasma/fibrin (PRP/PRF) and hyaluronic acid (HA) on cartilage regeneration and, in the case of HA injections, also on the clinical outcome can be assumed. The role of a combination therapy with use of intra-articular corticosteroids is lacking in the absence of adequate study data and cannot be defined yet. With regard to adipose tissue-based cell therapy, the current scientific data do not yet justify any recommendation for its use. Further studies also regarding application intervals, timing and differences in different joints are required.

The Working Group of the German Orthopedic and Trauma Society (DGOU) on Tissue Regeneration has published recommendations on the indication of different surgical approaches for treatment of full-thickness cartilage defects in the knee joint in 2004, 2013 and 2016. Based upon new scientific knowledge and new developments, this recommendation is an update based upon the best clinical evidence available. In addition to prospective randomised controlled clinical trials, this also includes studies with a lower level of evidence. In the absence of evidence, the decision is based on a consensus process within the members of the working group. The principle of making decision dependent on defect size has not been changed in the new recommendation either. The indication for arthroscopic microfracturing has been reduced up to a defect size of 2 cm(2) maximum, while autologous chondrocyte implantation is the method of choice for larger cartilage defects. Additionally, matrix-augmented bone marrow stimulation (mBMS) has been included in the recommendation for defects ranging from 1 to 4.5 cm(2). For the treatment of smaller osteochondral defects, in addition to osteochondral transplantation (OCT), mBMS is also recommended. For larger defects, matrix-augmented autologous chondrocyte implantation (mACI/mACT) in combination with augmentation of the subchondral bone is recommended.

IntroductionThe treatment of patients with ISJ dysfunction is difficult due to the multifactorial causes of pain and various problems in clarification. Treatment includes physical therapy, corticosteroids, prolotherapy, radiofrequency denervation and sacroiliac joint fusion. A new option for the surgical treatment of ISG dysfunction is the Torpedo implant system. For a safe fusion, only 2 implants are needed, which are available in lengths of 30-50 mm. The new implant system has been tested in pilot studies for efficacy and biocompatibility with good results. For further documentation for the Torpedo implant system, a comparative study against the iFuse system was carried out.Material and MethodsTwo different implants were used: Group 1: Deltacor Torpedo, Group 2: iFuse implants (Si-Bone). The data generated during admission and subsequent check-ups (VAS, ODI, opioid use) were entered into an evaluation file set up for this purpose. Follow-up appointments were set at 1 month, 3, 6 and 12 months postoperatively.ResultsThe data of 65 patients were evaluated comparatively. In all comparisons, only very small effect sizes were found with regard to the differences in the decrease in pain intensities, so that equivalent effectiveness of the two methods could initially be postulated from a clinical point of view. Most patients in both groups reported taking opioids to treat pain before surgery. According to the decrease in pain intensity, opioid treatment could be discontinued in some patients after the operation. After 12 months, the number of patients treated with opioids decreases to 23% in group 1 and to 17% in group 2. The success of the fusions with the two methods can also be proven by image documentation, from which the position of the implants can also be clearly recognised. In no case was there any loosening.DiscussionOverall, the evaluation of this study allows the conclusion that both implant systems can be successfully used for the treatment of patients with ISJ syndrome. The present results should be confirmed in further comparative studies with the proposed evaluation methods.

The subjective analysis of conventional radiography represents the principal method for bone diagnostics in endoprosthetics. Alternative objective quantitative methods are described but not commonly used. Therefore, semi-quantitative methods are tested using digital computation and artificial intelligence to standardize, simplify, and ultimately improve the assessment. This study aimed to evaluate the correlation between relative density progressions and clinical outcomes. Radiographs and clinical examinations before and 24 and 48 weeks after surgery were obtained from sixty-eight patients with a modular hip stem. For the calculation of the relative bone density, the modal gray values of the Gruen zones were measured using ImageJ and were normalized by gray values of the highest and lowest ROI. The clinical outcomes were measured according to the Harris hip score before evaluating them for correlations. Analyses were performed separately for subgroups and bone regions. The Harris hip score increased from 44.15 ± 15.00 pre-operatively to 66.20 ± 13.87 at the latest follow-up. The relative bone density adjustment of Gruen zone 7 showed a significant correlation to its clinical outcome. Other bone adaptations could be realistically reproduced and differences by regional zones and patients' histories visualized. Next to the simplicity and that no additional examination is required, the method provides good semi-quantitative results and visualizes adaptations, which make it suitable for use.

ZusammenfassungDie Behandlung von Patienten mit ISG-Dysfunktion ist aufgrund der multifaktoriellen Schmerzursachen und vielfältigen Probleme bei der Abklärung schwierig. Die Behandlung umfasst physikalische Therapie, Kortikosteroide, Prolotherapie, Hochfrequenzdenervation und Iliosakralgelenkfusion. Eine neue Option für die operative Behandlung von ISG-Dysfunktionen stellt das Torpedo-Implantatsystem dar. Für eine sichere Fusion werden nur 2 Implantate benötigt, die in Längen von 30–50 mm angeboten werden. Das neue Implantatsystem wurde in Pilotstudien auf Wirksamkeit und Biokompatibilität mit guten Resultaten geprüft. Zur weiteren Dokumentation für das Torpedo-Implantatsystem wurde eine Vergleichsstudie gegen das iFuse-System durchgeführt.Es wurden 2 unterschiedliche Implantate verwendet: Gruppe 1: Deltacor Torpedo, Gruppe 2: iFuse-Implantate (Si-Bone). Die bei der Aufnahme und bei den nachfolgenden Kontrolluntersuchungen erstellten Daten (VAS, ODI, Opioidverbrauch) wurden in eine zu diesem Zweck eingerichtete Auswertungsdatei eingetragen. Als Nachuntersuchungstermine wurden 1 Monat, 3, 6 und 12 Monate postoperativ festgelegt.Es wurden die Daten von 65 Patienten vergleichend ausgewertet. Bei allen Vergleichen zeigten sich hinsichtlich der Unterschiede im Rückgang der Schmerzintensitäten nur sehr geringe Effektstärken, sodass unter klinischen Aspekten zunächst eine gleichwertige Wirksamkeit beider Methoden postuliert werden konnte. Die meisten Patienten beider Gruppen gaben an, vor der Operation Opioide zur Schmerzbehandlung eingenommen zu haben. Entsprechend dem Rückgang der Schmerzintensität konnte bereits nach der Operation bei einigen Patienten die Opioidbehandlung abgesetzt werden. Nach 12 Monaten verringerte sich die Zahl der mit Opioiden behandelten Patienten in Gruppe 1 auf 23% und in Gruppe 2 auf 17%. Die Erfolge der Fusionen mit beiden Verfahren lassen sich zusätzlich an einer Bilddokumentation belegen, aus der auch die Lage der Implantate deutlich erkannt werden kann. In keinem Fall war eine Lockerung festzustellen.Insgesamt lässt die Auswertung dieser Studie das Resümee zu, dass beide Implantatsysteme erfolgreich zur Behandlung von Patienten mit ISG-Syndrom eingesetzt werden können. In weiteren Vergleichsstudien mit den vorgeschlagenen Auswertungsmethoden sollten die vorliegenden Resultate überprüft werden.

Cartilage defects in the knee can be caused by injury, various types of arthritis, or degeneration. As a long-term consequence of cartilage defects, osteoarthritis can develop over time, often leading to the need for a total knee replacement (TKR). The treatment alternatives of chondral defects include, among others, microfracture, and matrix-associated autologous chondrocyte implantation (M-ACI). The purpose of this study was to determine cost-effectiveness of M-ACI in Germany with available mid- and long-term outcome data, with special focus on the avoidance of TKR. We developed a discrete-event simulation (DES) that follows up individuals with cartilage defects of the knee over their lifetimes. The DES was conducted with a status-quo scenario in which M-ACI is available and a comparison scenario with no M-ACI available. The model included 10,000 patients with articular cartilage defects. We assumed Weibull distributions for short- and long-term effects for implant failures. Model outcomes were costs, number of TKRs, and quality-adjusted life years (QALYs). All analyses were performed from the perspective of the German statutory health insurance. The majority of patients was under 45 years old, with defect sizes between 2 and 7 cm2 (mean: 4.5 cm2); average modeled lifetime was 48 years. In the scenario without M-ACI, 26.4% of patients required a TKR over their lifetime. In the M-ACI scenario, this was the case in only 5.5% of cases. Thus, in the modeled cohort of 10,000 patients, 2700 TKRs, including revisions, could be avoided. Patients treated with M-ACI experienced improved quality of life (22.53 vs. 21.21 QALYs) at higher treatment-related costs (18,589 vs. 14,134 € /patient) compared to those treated without M-ACI, yielding an incremental cost‐effectiveness ratio (ICER) of 3376 € /QALY. M-ACI is projected to be a highly cost‐effective treatment for chondral defects of the knee in the German healthcare setting.

To determine the current status and demand of meniscal allograft transplantation (MAT) in Germany among members of the German Knee Society (= Deutsche Kniegesellschaft; DKG). An online survey was conducted between May 2021 and June 2021 and sent to all members of the DKG. The survey questionnaire consisted of 19 questions to determine the demand and technical aspects of MAT among the participants and to identify areas of improvement in MAT in Germany. Overall, 152 participants, 136 (89.5%) from Germany, 8 (5.3%) from Switzerland, 6 (4.0%) from Austria, and 2 (1.3%) from other countries completed the online survey, with the majority working in non-academic institutions. According to the regulations of the DKG, 87 (57.2%) participants were board certified as specialized knee surgeons and 97 (63.8%) worked primarily in the field of orthopedic sports medicine. MAT was considered clinically necessary in Germany by 139 (91.5%) participants. Patient age (83.6%), post-meniscectomy syndrome in isolated lateral (79.6%) and medial (71.7%) meniscus deficiency, and functional and athletic demands (43.4%) were the most important determinants to consider MAT in patients. Participants reported that reimbursement (82.9%), jurisdiction over the use of donor grafts (77.6%), and the availability of meniscal allografts (76.3%) are the main challenges in performing MAT in Germany. The most frequently used meniscal allograft types by 54 (35.5%) participants who had already performed MAT were fresh-frozen grafts (56.6%), peracetic acid–ethanol sterilized grafts (35.9%), and cryopreserved grafts (7.6%). Participants reported to perform suture-only fixation more often than bone block fixation for both medial (73.6% vs. 22.6%) and lateral (69.8% vs. 24.5%) MAT. More than 90% of the responding members of the DKG indicated that MAT is a clinically important and valuable procedure in Germany. Reimbursement, jurisdiction over the use of donor grafts, and the availability of meniscal allografts should be improved. This survey is intended to support future efforts to facilitate MAT in daily clinical practice in Germany. Level V.