Background One of complications of the reverse shoulder arthroplasty is acromion fractures, and its therapy is controversial. The aim of the study was to investigate the double-plate osteosynthesis for these fractures. Methods An acromion type III fracture according to classification of Levy was simulated in 16 human shoulder cadavers, and the specimens were randomly divided into two groups . Single-plate osteosynthesis was performed in the first group (locking compression plate) and double-plate osteosynthesis (locking compression plate and one-third tubular locking plate) in the second group. Biomechanical testing included cycling load and load at failure on a material testing machine. During the test, the translation was measured using an optical tracking system. Results The load at failure for the single-plate osteosynthesis was 167 N and for the double-osteosynthesis 233.7 N ( P = 0.328). The average translation was 11.1 mm for the single-plate osteosynthesis and 16.4 mm for the double-plate osteosynthesis ( P = 0.753). The resulting stiffness resulted in 74.7 N/mm for the single-plate osteosynthesis and 327.9 N/mm for the double-plate osteosynthesis ( P = 0.141). Discussion Results of the biomechanical study showed that double-plate osteosynthesis had biomechanical properties similar to those of single-plate osteosynthesis for an acromion type III fracture at time point zero. The missing advantages of double-plate osteosynthesis can be explained by the choice of plate configuration.

Background Supracondylar osteotomies are a frequently and successfully used technique in the treatment of coronal plane deformities and unicompartmental osteoarthritis of the knee. While lateral open wedge techniques are common for valgus deformities, the data about medial open wedge techniques for varus deformities is sparse. The aim of this study was to compare the biomechanical properties of medial and lateral open wedge osteotomies using a locking Tomofix® plate (DePuy Synthes, Oberdorf, Switzerland). Our hypothesis was that there would be no difference regarding biomechanical outcome parameters between these two groups. Methods Medial and lateral open wedge osteotomies were performed in composite bone model as routine. Each experimental group contained 6 constructs. Standardized osteotomy gaps of ten millimeters were performed and Tomofix® plates were fixed to third generation composite bones. The constructs were subsequently mounted into a servohydraulic testing machine. Axial and torsional loadings were applied as described in previous experimental studies. All specimens were subject to a load to failure mode with the mechanism of failure being noted. Findings Both experimental groups showed comparable biomechanical properties under axial and torsional loadings. Mean high force axial stiffness was 3772 N/mm for lateral and 4185 N/mm for the medial construct. Significant differences were noted for torsional stiffness under low- (0 N) and mid-force (150 N) loadings (P = 0.002; P = 0.009), favoring the medial open wedge constructs. Interpretation Medial open wedge osteotomy yields comparable biomechanical stability to the lateral open wedge procedure on the distal femur in a composite bone model.

Verletzungen der lateralen Klavikula und des Akromioklavikulargelenks (ACG) sind häufige, alltagsrelevante Ereignisse, die insbesondere aktive Erwachsene im Alter von 20 bis 40 Jahren betreffen. Für die Einteilung von ACG-Verletzungen ist die Rockwood-Klassifikation etabliert. Laterale Klavikulafrakturen werden nach Neer resp. Jäger und Breitner klassifiziert. Eine neuere Einteilung ist die Klassifikation nach Cho. Je nach vorliegendem Verletzungsmuster und insbesondere vorliegender Instabilität finden sowohl konservative als auch operative Versorgungsstrategien Anwendung. Dieser Beitrag gibt einen Überblick über einzelne Versorgungskonzepte.

Injurie to the lateral clavicle and acromioclavicular joint (ACJ) are frequent events which are relevant to everyday life and particularly affect active adults at the age of 20-40 years. The Rockwood classification has been established for the classification of ACJ injuries. Lateral clavicle fractures are classified according to the Neer classification or the Jäger and Breitner classification. A newly established classification is the Cho classification. Depending on the injury pattern and in particular the presence of instability, various conservative and surgical care strategies are used. This article provides an overview of the various treatment concepts.

Symptomatische Bandscheibenvorfälle sind aufgrund ihrer zum Teil schweren Schmerzsymptomatik und möglicherweise neurologischen Ausfälle in der Akutphase nicht mit sportlicher Betätigung vereinbar. Wichtig ist es, gemeinsam mit den Sportlern nach Abklingen dieser Phase einen individuellen Belastungsaufbau zu planen. Die beeinflussenden Faktoren dabei sind strukturelle Schäden, zuvor ausgeübte Sportart und Trainingszustand sowie Schmerzen und neurologische Defizite. Anhand von Expertenkonsensus und überwiegend tierexperimentell nachgewiesenen Pathomechanismen wurden Vorschläge zum Belastungsaufbau publiziert. Folglich kann nach eingestellter Schmerzsymptomatik mit vorsichtigem Trainingsaufbau nach etwa 1–3 Wochen begonnen werden. Hierzu gehören Stabilisierung der Rückenmuskulatur sowie vorsichtige Mobilisation der Wirbelsäule. Rotations- und Axialbelastung sollten initial nur sehr zurückhaltend gesteigert werden. Ab ungefähr 6 Wochen kann mit „Low-impact“-Sportarten und nach etwa 12 Wochen mit „High-impact“-Sportarten begonnen werden. Eine individuelle Steuerung zur Vermeidung von Chronifizierung der Schmerzen sowie Prophylaxe von degenerativen Veränderungen ist anzustreben.

BACKGROUND:Symptomatic herniated discs are not compatible with physical activity due to severe pain and possible neurological deficits in the acute phase. Once this phase has subsided, it is important to plan an individualized load build-up. The influencing factors are structural damage, the type of sport previously practiced and training status, as well as pain and neurological deficits. LOAD BUILD-UP:Based on expert consensus and pathomechanisms that have predominantly been proven in animal experiments, suggestions for load build-up have been published. Consequently, once the pain symptoms have been stabilized, careful training can be started after about 1-3 weeks. This includes stabilization of the back muscles and careful mobilization of the spine. Initially, rotational and axial loads should only be increased very cautiously. Low-impact sports can be started from around 6 weeks and high-impact sports from around 12 weeks. Individual medical advice to avoid chronic pain and prevention of degenerative changes should be prioritized.

The influence of the subscapularis tendon on reverse total shoulder arthroplasty (RTSA) has been discussed controversially. The aim of the study was to investigate the subscapularis-sparing approach for RTSA and the effect of the intact subscapularis tendon. This retrospective comparative study included 93 patients. Among these, 55 underwent the deltopectoral subscapularis-sparing approach, and in 38 cases, the standard deltopectoral approach with subscapularis tenotomy was applied. At the final follow-up, representative shoulder scores were measured, radiographs were taken in two planes, and shoulder sonography was performed. The subscapularis-sparing group showed a significantly higher Constant score (71.8 vs. 65.9 points) and adapted Constant score if the subscapularis tendon was shown to be intact in the postoperative sonography (85.2

Die Infiltrationstherapie mit Kortikosteroiden oder Hyaluronsäure stellt eine wichtige Säule der konservativen Behandlung der Gonarthrose dar. Die Verwendung von plättchenreichem Plasma (PRP) gewinnt hierbei zunehmend an Bedeutung. Dieses systematische Review untersuchte das klinische Outcome der Kombinationstherapie aus Hyaluronsäure und PRP im Vergleich mit den Monotherapien anhand einer Literaturrecherche.

Objective: Clinical outcome data for the novel minced cartilage procedure are sparse. While good results have been shown for the knee joint, this is the first report in the current literature regarding this increasingly important procedure in the glenohumeral joint. Case Description: A 33-year-old handyman with a cartilage defect in the humeral head underwent an all arthroscopic one-stage cartilage repair with the AutoCartTM procedure (Arthrex GmbH, Munich, Germany). A senior specialist examined the patient before surgery, five-, 12-and 24-weeks post-surgery. Outcome parameters (Constant-Murley Score, UCLA Shoulder Score and ASES Score) and radiographic imaging were recorded. Results: At six months, follow-up the outcome parameter showed excellent results, the joint pain decreased to numeric rating scale (NRS) 0. The postoperative magnetic resonance imaging (MRI) revealed a thin cartilage layer in the treated area with sufficient integration to the surrounding tissue. The cartilage in the former defect zone presented a homogeneous signal, which was comparable to the intact cartilage. Conclusion: This case report underlines the growing interest in single-stage arthroscopic minced cartilage procedures and shows promising results in the glenohumeral joint. Yet, larger investigations with long-term follow-up are necessary to provide reliable clinical data to determine if comparable results can be achieved over time.

Purpose: Torn anterior cruciate ligaments in children are rare injuries. The incidence of concomitant avulsion fracture in the skeletally immature patient is high. Reports of arthroscopic reconstruction in the literature are sparse.Case Presentation: We present the case of a femoral avulsion fracture of the anterior cruciate ligament in a seven-year-old girl. The patient underwent arthroscopic refixation with DynacordTM Suture and Suture Button. At a follow-up of 8 weeks, the patient had free range of motion and a stable knee, with a negative Lachman-and Pivot-Shift-test in particular.Conclusion: Refixation of femoral avulsion fracture can lead to good results. Open physes and size of the knee should be taken into account. Anatomic reconstruction is compulsory to receive bone on bone healing.

Background Anatomic total shoulder arthroplasty (TSA) has been continuously developed and current designs include stemless or canal-sparing humeral components. In the literature stemless and canal sparing TSA showed good clinical and radiographic results, which were comparable to stemmed TSA. Objective The aim of this study was to determine the short-term clinical and radiological outcomes of a new stemless TSA design. Methods A prospective multicentre study including 154 total shoulder arthroplasty patients with a follow up of 12 months was performed. At the time of follow up 129 patients were available for review. The adjusted Constant Murley score, 1 Oxford Shoulder Score, EQ-5D-5L score and radiographs were examined preoperatively, 3 and 12 months after the implantation of the new stemless TSA implant GLOBAL ICON™ (DePuy Synthes, Warsaw, IN, USA). Complications were documented. Results Implant Kaplan-Meier survivorship was 98.7% at 12 months. From baseline to 12 months follow-up, all scores showed a progressive significant mean improvement. The mean adjusted Constant score increased from 42.3 to 96.1 points (p<0.001). The Oxford Shoulder Score showed an increase of 21.6 points (p<0.001). The postoperative radiographs showed no continuous radiolucent lines, subsidence, aseptic loosening or progressive radiolucency, but one osteolytic lesion was observed. Only 2 prostheses were revised. Conclusion The new GLOBAL ICON stemless TSA showed good clinical and radiographic results at short-term follow up which were comparable to early results of other stemless TSA. Further studies with longer follow up are needed in the future.

Weichteilige Stabilisierungsverfahren zeigen sich ineffektiv bei der Behandlung der vorderen Schulterinstabilität und gleichzeitigem Vorliegen eines anterioren Glenoiddefekts. Daher besteht die Notwendigkeit für knöchern-stabilisierende Verfahren. Hier konkurriert der Korakoidtransfer nach Latarjet mit der Transplantation eines autologen Beckenkammspans (ICBGT). Beide Verfahren kommen regelhaft zur Anwendung, eine eindeutige Überlegenheit einer Technik konnte bisher jedoch nicht nachgewiesen werden. Die vorliegende Studie vergleicht beide Verfahren in einer prospektiv randomisierten Untersuchung miteinander. Die Autoren vermuten eine Überlegenheit der Beckenkammspantransplantation hinsichtlich etablierter Scores zur Schulterinstabilität.

Purpose Reconstruction of the medial patellofemoral ligament (MPFL) is an established procedure to restore patellar stability. Aim of this study is to evaluate the results of a dynamic MPFL reconstruction technique in a large university hospital setting. Methods Two hundred and thirteen consecutive patients with 221 knees were surgically treated for recurrent lateral patellar dislocation. All patients obtained dynamic reconstruction of the MPFL with detachment of the gracilis tendon at the pes anserinus while maintaining the proximal origin at the gracilis muscle. Patellar fixation was performed by oblique transpatellar tunnel transfer. Follow-up data including Kujala and BANFF score, pain level as well as recurrent patella instability were collected at a minimum follow-up of 2 years. Results Follow-up could be obtained from 158 patients (71%). The mean follow-up time was 5.4 years. Mean pain level was 1.9 ± 2.0 on the VAS. Mean Kujala score was 78.4 ± 15.5. Mean BANFF score was 62.4 ± 22.3. MPFL-reconstructions that were performed by surgeons with a routine of more than ten procedures had a significantly shorter surgical time 52.3 ± 17.6 min. Male patients yielded higher satisfaction rates and better clinical scores compared to females. Complications occurred in 27.2% of procedures, 20.9% requiring revision surgery of which were 9.5% related to recurrent patellar instability. 78% of all patients indicated they would undergo the procedure again. Conclusion Dynamic MPFL reconstruction presents a reproducible procedure with increased complication rates, inferior to the results of static reconstruction described in the literature. Despite, it appears to be an efficient procedure to restore patellar stability in a large university hospital setting, without the necessity for intraoperative fluoroscopy. Trial registration The study was registered in ClinicalTrials.gov with the registration number NCT04438109 on June 18th 2020.

Aims and Objectives: Patients with isolated medial gonarthrosis benefit from a treatment with a unicompartmental knee arthroplasty (UKA) compared to a total knee arthroplasty (TKA). They have a shorter rehabilitation time, better function, lower morbidity and a higher satisfaction rate. However, the revision rate is higher than in patients with TKA. Patient selection and the resulting incorrect indication may be one reason. Hamilton et al.’s research group prepared a radiological “decision aid” for the indication of a UKA. The aim of this study was to validate this uncomplicated diagnostic procedure based on intraoperative findings. Materials and Methods: In this prospective study, 85 patients received routinely conventional x-rays. Strictly lateral and anterior-posterior view as well as varus/valgus stress x-rays were taken. Using Hamilton et al.’s “desiscion aid”, the x-ray images were preoperatively evaluated with regard to medial and lateral cartilage damage and the function of the anterior cruciate ligament. The cartilage damage of the individual tibial and femoral compartments was also scaled and documented intraoperatively. The results of the decision aid were validated with regard to the intraoperative findings. Indication-justifying cartilage damage was defined as focal complete cartilage loss. The sensitivity (SEN) and specificity (SPE) of decision aid with regard to cartilage damage in the medial and lateral compartments and the functionality of the anterior cruciate ligament were determined. Results: In the area of the medial compartment, decision aid has a SEN and PES of 79.4% and 82.4% respectively. The SEN and SPE for lateral compartments are 98.5% and 55.0%, respectively. Intact ACLs are correctly diagnosed at 94.7%. Insufficient ACLs at 33.3%. Conclusion: These data suggest that according to our findings, only about 2 out of 10 patients are not reliably diagnosed with medial gonarthrosis. However, about 2 out of 10 patients are diagnosed with medial gonarthrosis, which does not yet have to be treated with UKA. Furthermore, it could be shown that almost all patients with a completely laterally preserved cartilage are also recognized as such. However, every second patient with relevant cartilage damage is not radiologically identified. These data refer only to the radiological findings. Coupled with the patient’s medical history and clinic, the “Desicion Aid” is a very good aid for the correct indication for a UKA.

Over the past decades many innovations were introduced in total knee arthroplasty (TKA) focusing on implant longevity and higher procedural precision; however, there are still a high number of dissatisfied patients. It was reported that better anatomical alignment may result in improved patient outcome; however, current technologies have limitations to achieve this. The aim of this video article is to describe the technique of individualized alignment in TKA with the use of image-based robotic assistance.The technology is based on an individual patient knee model computed from segmented computed tomography (CT) scans. A preoperative planning of prosthesis position is conducted following the principle of kinematic alignment. Intraoperatively the soft tissue envelope is recorded and the computer predicts the gap balance based on the virtual planning. The prosthesis position is then adapted to achieve balanced gaps and to avoid soft tissue release. This technique is shown in a cadaver operation and clinical examples of two patients are described.With the combination of anatomically oriented prosthesis positioning and minor adaptations with respect to the soft tissue, an individualized alignment is achieved with reduced need of soft tissue release. The robotic-assisted surgery guarantees a precise implementation of the planning. The initial experience showed a promising outcome in short-term follow-up.

Today, there is an almost endless variety of knee prosthesis models on the market from which the surgeon can choose. Although the designs appear closer and closer to one another, the industry makes a great effort to emphasise different features as beneficial and a stand-alone. It is increasingly difficult to keep an overview and to assess the clinical relevance of the diverse features. There is a clear lack of independent comparative studies and evidence is low. Nevertheless, different design philosophies require special surgical techniques, so that the surgeon must be familiar with the peculiarity of his/her prosthesis. Also, a differentiated indication for different designs appears to be an interesting concept. The aim of this essay is to give a brief overview of the major design concepts of current unconstrained knee prosthesis designs and their differences regarding biomechanics and kinematics.

Zusammenfassung Mittlerweile findet sich ein schier unendliches Angebot an Knieprothesenmodellen auf dem Markt, aus denen der Chirurg für seine Versorgung wählen kann. Obwohl sich die Designs auf den ersten Blick immer weiter annähern und ähneln, betreibt die Industrie einen hohen Aufwand, unterschiedliche Designmerkmale als Alleinstellung herauszuarbeiten. Für den Anwender ist es zunehmend schwierig, den Überblick zu behalten und die tatsächliche Relevanz der Features zu bewerten. Unabhängige vergleichende wissenschaftliche Arbeiten sind Mangelware und die Evidenz entsprechend gering. Dennoch erfordern unterschiedliche Designphilosophien ein tiefgründiges konzeptionelles Verständnis und besondere Operationsalgorithmen, sodass sich der Chirurg mit der von ihm benutzten Prothese entsprechend gut auskennen muss. Interessant ist auch eine sich aus diesem Wissen ergebende indikationsbezogene Prothesenauswahl. Im Folgenden wird ein kurzer Überblick über die wesentlichen Konzepte der ungekoppelten Primärprothesen gegeben und deren klinisch relevante Unterschiede in Bezug auf die Biomechanik und den klinischen Einsatz angesprochen.

Background: This biomechanical cadaveric in vitro study aimed to evaluate and compare the dynamic elongation behavior and ultimate failure strength of tibial adjustable-length loop cortical button versus interference screw fixation in quadriceps tendon-based anterior cruciate ligament reconstruction. Methods: Sixteen human quadriceps tendons were harvested and fixed into porcine tibiae using either biodegradable interference screw (n = 8) or adjustable loop device (n = 8) fixation. An acrylic block was utilized for femoral adjustable loop device fixation for both groups. All constructs were precyded for 10 times at 0.5 Hz and manually retensioned before tested in position and force control mode each for 1000 cycles at 0.75 Hz according to in vitro loading conditions replicating the in vivo ACL environment. Subsequently, an ultimate failure test at 50 mm/min was performed with mode of failure noted. Findings: Tibial IS fixation showed no statistically significant differences in the initial ( -0.46 vs. -0.47 mm; P = 0.9780), dynamic (2.18 mm vs. 2.89 mm; P = 0,0661), and total elongation (1.72 mm vs. 2.42 mm; P = 0,0997) compared to adjustable loop device fixation. The tibial button fixation revealed an increased ultimate failure load (743.3 N vs. 606.3 N; P = 0.0027), while stiffness was decreased in comparison to screw fixation (133.2 N/mm vs. 153.5 N/mm; P = 0,0045). Interpretation: Anterior cruciate ligament reconstruction for quadriceps tendon graft using a tibial adjustable length loop cortical button provides for comparable dynamic stabilization of the knee with increased ultimate failure load at decreased stiffness compared to screw fixation.

Clinical scores and motion-capturing gait analysis are today's gold standard for outcome measurement after knee arthroplasty, although they are criticized for bias and their ability to reflect patients' actual quality of life has been questioned. In this context, mobile gait analysis systems have been introduced to overcome some of these limitations. This study used a previously developed mobile gait analysis system comprising three inertial sensor units to evaluate daily activities and sports. The sensors were taped to the lumbosacral junction and the thigh and shank of the affected limb. The annotated raw data was evaluated using our validated proprietary software. Six patients undergoing knee arthroplasty were examined the day before and 12 months after surgery. All patients reported a satisfactory outcome, although four patients still had limitations in their desired activities. In this context, feasible running speed demonstrated a good correlation with reported impairments in sports-related activities. Notably, knee flexion angle while descending stairs and the ability to stop abruptly when running exhibited good correlation with the clinical stability and proprioception of the knee. Moreover, fatigue effects were displayed in some patients. The introduced system appears to be suitable for outcome measurement after knee arthroplasty and has the potential to overcome some of the limitations of stationary gait labs while gathering additional meaningful parameters regarding the force limits of the knee.