Analysis of postoperative complications 5 years after osteosynthesis of patella fractures-a retrospective, multicenter cohort study.

PURPOSE: The study aims to investigate the influence of patient- and fracture-specific factors on the occurrence of complications after osteosynthesis of patella fractures and to compare knee joint function, activity, and subjective pain levels after a regular postoperative course and after complications in the medium term. METHODS: This retrospective, multicenter cohort study examined patients who received surgery for patella fracture at level 1 trauma centers between 2013 and 2018. Patient demographics and fracture-specific variables were evaluated. Final follow-up assessments included patient-reported pain scores (NRS), subjective activity and knee function scores (Tegner Activity Scale, Lysholm score, IKDC score), complications, and revisions. RESULTS: A total of 243 patients with a mean follow-up of 63.4 ± 21.3 months were included. Among them, 66.9% of patients underwent tension band wiring (TBW), 19.0% received locking plate osteosynthesis (LPO), and 14.1% underwent screw osteosynthesis (SO). A total of 38 patients (15.6%) experienced complications (TBW: 16.7%; LPO: 15.2%; SO: 11.8%). Implant-related complications of atraumatic fragment dislocation and material insufficiency/dislocation, accounted for 50% of all complications, were significantly more common after TBW than LPO (p = 0.015). No patient-specific factor was identified as a general cause for increased complications. Overall, particularly following complications such as limited range of motion or traumatic refracture, functional knee scores were significantly lower and pain levels were significantly higher at the final follow-up when a complication occurred. Implant-related complications, however, achieved functional scores comparable to a regular postoperative course without complications after revision surgery. CONCLUSION: The present study demonstrated that implant-related complications occurred significantly more often after TBW compared to LPO. The complication rates were similar in all groups.

Late-stage rehabilitation after anterior cruciate ligament reconstruction: A multicentre randomised controlled trial (PReP).

BACKGROUND: At the completion of formal rehabilitation after anterior cruciate ligament reconstruction, functional capacity is only restored in a small proportion of affected individuals. Therefore, the end of formal rehabilitation is not the end of functional rehabilitation. OBJECTIVE: To compare adherence to and effectiveness of a late-stage rehabilitation programme with usual care after anterior cruciate ligament (ACL) reconstruction. METHODS: This prospective, double-blind, multicentre, parallel group, randomised controlled trial, included people aged 18 to 35 years after formal rehabilitation completion (mean [SD] 241 [92] days post-reconstruction). Participants were block-randomised to a 5-month neuromuscular performance intervention (Stop-X group) or usual care (medically prescribed standard physiotherapy, individual formal rehabilitation, home-exercises). All outcomes were measured once/month. Primary outcome was the normalised knee separation distance on landing after drop jump. Baseline-adjusted linear mixed models were calculated. RESULTS: In total, 112 participants (Stop-X: 57; Usual care: 55,) were analysed. Initially, mean (SD) intervention frequency (units/week) was higher in the Stop-X than the Usual care group: 2.65 (0.96) versus 2.48 (1.14) units/week in the first and 2.28 (1.02) versus 2.14 (1.31) units/week in the second month. No between-group*time(*baseline)-differences were found for the primary outcome. Between-group*time-effects favoured the Stop-X-group at 2 months (fewer self-reported knee problems during sport, KOOS-SPORT) (estimate = 64.3, 95 % CI 24.4-104.3 for the Stop-X), more confidence to return to sport (ACL-RSI) (62.4, 10.7-114.2), fewer pain-associated knee problems (KOOS-PAIN) (82.8, 36.0-129.6), improved everyday activity abilities (KOOS-ADL) (71.1, 6.4-135.7), and improved limb symmetry index in the front hop for distance at 3 and 4 months (0.34, 0.10-0.57; 0.31, 0.08-0.54). No between-group*time-effects occurred for kinesiophobia, symptom-associated knee problems or balance hops performance. At the end of the intervention, 79 % of the Stop-X and 70 % of the Usual care participants (p < 0.05) had successfully returned to their pre-injury sport type and level. CONCLUSIONS: The Stop-X intervention was slightly superior to usual care as part of late-stage rehabilitation after ACL-reconstruction. The small benefit might justify its use after formal rehabilitation completion.

Most Publications Regarding Arthroscopic Treatment of Posterolateral Corner Injuries of the Knee Have a Low Level of Evidence and Provide Limited Information to Determine the Most Effective Treatment.

Purpose: To examine the Level of Evidence and overall quality of studies addressing arthroscopic posterolateral corner reconstructions of the knee. Methods: A search was performed using the PubMed/Medline, Web of Science, and Google Scholar databases for all studies investigating arthroscopic treatment of posterolateral corner injuries of the knee. Studies reporting outcomes or describing arthroscopic techniques for treatment of posterolateral corner injuries of the knee were the focus of this analysis. Clinical as well as biomechanical and cadaveric studies were included. Studies only investigating open techniques were excluded. Two independent reviewers determined the level of evidence for each included study using the criteria established by the Journal of Bone and Joint Surgery and scored each clinical study from 0 to 100 based on 10 criteria from the modified Coleman Methodology Score. Results: Twenty-four studies matched the inclusion criteria. There were 6 cadaveric technique descriptions, 6 clinical technique descriptions, 3 biomechanical studies, 4 technical repair descriptions, and 5 clinical outcome studies. Thirty-eight percent of all studies were of Level V evidence. Fifty percent of studies were of Level IV evidence, and 12% of studies were of Level III evidence. The mean modified Coleman Methodology Score for the clinical studies was 43 ± 11.4, which is regarded as poor, mainly due to the limited number of patients and the retrospective nature of the studies. Conclusions: Most studies addressing arthroscopic posterolateral corner reconstruction of the knee are of low level of evidence and provide limited information about the best treatment options. Clinical Relevance: The number of publications on arthroscopic posterolateral corner reconstruction techniques continues to rise. This systematic review evaluates the level of evidence of these studies.

Management after acute injury of the anterior cruciate ligament (ACL). Part 3: Recommendation on surgical treatment.

PURPOSE: The aim of this consensus project was to give recommendations regarding surgical treatment of the anterior cruciate ligament (ACL) injured patient. METHODS: For this consensus process, an expert, steering and rating group was formed. In an initial online meeting, the steering group, together with the expert group, formed various key topic complexes for which multiple questions were formulated. For each key topic, a structured literature search was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Sufficient consensus was defined as 80% agreement. RESULTS: During this consensus process, 30 topics regarding the surgical management and technique of ACL reconstruction were identified. The literature search for each key question resulted in 30 final statements. Of these 30 final statements, all achieved consensus. CONCLUSIONS: This consensus process has shown that surgical treatment of ACL injury is a complex process. Various surgical factors influence patient outcomes. The proposed treatment algorithm can be used as a decision aid for the surgeon. LEVEL OF EVIDENCE: Level V.

The End of the Formal Rehabilitation Is Not the End of Rehabilitation: Knee Function Deficits Remain After Anterior Cruciate Ligament Reconstruction.

OBJECTIVE: To rate athletes' functional ability and return to sport (RTS) success at the end of their individual, formal, medically prescribed rehabilitation after anterior anterior cruciate ligament (ACL) reconstruction. METHODS: In our prospective multicenter cohort study, 88 (42 females) adults aged 18-35 years after acute unilateral ACL rupture and subsequent hamstring grafting were included. All patients were prospectively monitored during their rehabilitation and RTS process until the end of their formal rehabilitation and RTS release. As outcome measures, functional hop and jump tests (front hop, balance hops, and drop jump screening test) and self-report outcomes (Knee Injury and Osteoarthritis Outcome Score, ACL-RTS after injury) were assessed. Literature-based cut-off values were selected to rate each performance as fulfilled or not. RESULTS: At 7.5 months (SD 2.3 months) after surgery, the percentage of participants meeting the functional thresholds ranged from 4% (Knee Injury and Osteoarthritis Outcome Score SPORT) and over 44% (ACL-RTS after injury sum score) to 59% (Knee Injury and Osteoarthritis Outcome Score activities of all daily living) in the self-report and from 29% (Balance side hop) to 69% (normalized knee separation distance) in performance testing. Only 4% fulfilled all the cut-offs, while 45% returned to the same type and level of sport. Participants who successfully returned to their previous sport (type and level) were more likely to be "over-cut-off-performers." CONCLUSIONS: The low share of the athletes who fulfilled the functional RTS criteria highlights the importance of continuing the rehabilitation measures after the formal completion to assess the need for and success of, inter alia, secondary-preventive therapies.

Cortical bone thickness on preoperative CT scans as predictor of bone quality in distal femur fractures: a retrospective study in Caucasians.

AIM: Distal femur fractures (DFF) are rare, but associated with high complication rates and mortality, particularly in patients with osteoporosis. To improve preoperative assessment, we analyzed if cortical bone thickness on CT and AP radiographs is associated with clinical parameters of bone quality. METHODS: Retrospective single-center study of adult patients presenting at a level-one trauma center, with a DFF between 2011 and 2020. Clinical parameters for bone quality, such as age, sex, body mass index (BMI), energy impact level of trauma, and known history of osteoporosis, were assessed. Mean cortical bone thickness (CBTavg) on AP radiograph was determined using a previously published method. Cortical thickness on CT scan was measured at 8 and 14 cm proximal to the articular surface of the lateral condyle. RESULTS: 71 patients (46 females) between 20 and 100 years were included in the study. Cortical thickness determined by CT correlated significantly with CBTavg measurements on AP radiograph (Spearman r = 0.62 to 0.80; p < 0.001). Cortical thickness was inversely correlated with age (Spearman r = - 0.341 to - 0.466; p < 0.001) and significantly associated with trauma impact level and history of osteoporosis (p = < 0.001). The CT-based values showed a stronger correlation with the clinical parameters than those determined by AP X-ray. CONCLUSION: Our results showed that cortical thickness of the distal femur correlates with clinical parameters of bone quality and is therefore an excellent tool for assessing what surgical care should be provided. Interestingly, our findings indicate that cortical thickness on CT is more strongly correlated with clinical data than AP radiograph measurements.

[Multiligament instabilities of the knee in sports injuries : An update of the Hamburg concept]. / Multiligamentäre Instabilitäten des Kniegelenkes bei Sportverletzungen : Ein Update zum "Hamburger Konzept".

BACKGROUND: Knee dislocation (KD) is a rare but severe injury of the knee joint, with a high rate of concomitant neurovascular injuries. The severity of the ligamentous injury, which is classified according to the Schenck classification, the mechanism of injury, concomitant injuries and individual factors determine the treatment strategy in KD. TREATMENT STRATEGY: Furthermore, a clear differentiation between high-velocity (HV) and low-velocity (LV) injuries is necessary. Generally, surgical treatment within 7-10 days should be aspired. Herein, the one-stage hybrid treatment using augmented ligament sutures (ligament bracing) in combination with primary ligament reconstruction (posterolateral and ACL) leads to very good functional results in the mid-term. Ultra-low-velocity (ULV) dislocations and those with concomitant peroneal lesions require a modified approach, due to a limited prognosis. During rehabilitation, the individual progress must be closely monitored and follow an early functional approach. In approximately 20% of all cases, early arthroscopic arthrolysis shows a high success rate.

S2k Guideline for Tibial Plateau Fractures - Classification, Diagnosis, and Treatment. / S2k-Leitlinie Tibiakopffraktur ­ Klassifikation, Diagnostik und Therapie.

Tibial plateau fractures are mostly complex and surgically demanding joint fractures, which require a comprehensive understanding of the fracture morphology, ligamentous and neurovascular injuries, as well as the diagnostic and therapeutic options for an optimal clinical outcome. Therefore, a standardised and structured approach is required. The success of the treatment of tibial plateau fractures relies on the interdisciplinary cooperation between surgical and conservative physicians in an outpatient and inpatient setting, physical therapists, patients and service providers (health insurance companies, statutory accident insurance, pension providers). On behalf of the German Society for Orthopaedics and Trauma Surgery (DGOU), the German Trauma Society (DGU) and the Society for Arthroscopy and Joint Surgery (AGA), under the leadership of the Fracture Committee of the German Knee Society (DKG), a guideline for tibial plateau fractures was created, which was developed in several voting rounds as part of a Delphi process. Based on the current literature, this guideline is intended to make clear recommendations and outline the most important treatment steps in diagnostics, therapy and follow-up treatment. Additionally, 25 statements were revised by the authors in several survey rounds using the Likert scale in order to reach a final consensus.

Anatomic repair and ligament bracing as an alternative treatment option for acute combined PCL injuries involving the posteromedial or posterolateral corner-results of a multicentre study.

INTRODUCTION: Combined PCL injuries involving the posteromedial/-lateral corner (PMC/PLC) usually require surgical management. Literature shows controversy regarding the standards of treatment. Suture-augmented repair leads to excellent results in acute knee dislocations but has not been investigated clinically in combined PCL injuries. The purpose of this multicentre study was to evaluate the clinical outcome of this technique in acute combined PCL injuries. MATERIALS & METHODS: N = 33 patients with acute combined PCL injuries involving the PMC/PLC were treated by one-stage suture repair with ligament bracing of the PCL and suture repair of the accompanying PMC/PLC injuries with/without ligament bracing or primary augmentation by semitendinosus autograft. Outcome was assessed by IKDC questionnaire, Lysholm Score, Tegner Activity Scale and KOOS. Additional PCL stress-radiography was performed. RESULTS: N = 31 patients with combined PCL injuries (female: male = 7:24; age 39.1 ± 13.8 years) with a follow-up of 16.8 ± 9.6 months were finally evaluated. 18 had PMC injuries, 13 PLC injuries. 32.2% presented with accompanying meniscal tears (70% medial meniscus). 19.4% showed cartilage injuries grade III-IV. Complications included one infection and four knee stiffnesses. Three had symptomatic postoperative instability, all affiliated to the PLC group. The IKDC was 69.8 ± 16.5, Lysholm score 85 ± 14.4 and KOOS 89.7 ± 8.1. Median loss of activity (Tegner) was 0.89 ± 1.31. Comparing PMC and PLC, all scores showed a tendency towards more favourable outcomes in the PMC group (n.s.). Stress-radiography showed an overall side-to-side difference of 3.7 ± 3.8 mm. Subgroup evaluation showed statistically significant better results (p = 0.035) of PMC (2.5 ± 1.5 mm) versus PLC (5.8 ± 5.6 mm). CONCLUSIONS: One-stage suture repair with ligament bracing is a viable technique for acute combined PCL injuries and predominantly leads to good and excellent clinical outcomes. Patients with PLC injuries show a tendency towards inferior outcomes and higher instability rates compared to PMC injuries. These results may help in therapy planning and counselling patients with these rare injury pattern. LEVEL OF EVIDENCE: Level II.

GSK3 and lamellipodin balance lamellipodial protrusions and focal adhesion maturation in mouse neural crest migration.

Neural crest cells are multipotent cells that delaminate from the neuroepithelium, migrating throughout the embryo. Aberrant migration causes developmental defects. Animal models are improving our understanding of neural crest anomalies, but in vivo migration behaviors are poorly understood. Here, we demonstrate that murine neural crest cells display actin-based lamellipodia and filopodia in vivo. Using neural crest-specific knockouts or inhibitors, we show that the serine-threonine kinase glycogen synthase kinase-3 (GSK3) and the cytoskeletal regulator lamellipodin (Lpd) are required for lamellipodia formation while preventing focal adhesion maturation. Lpd is a substrate of GSK3, and phosphorylation of Lpd favors interactions with the Scar/WAVE complex (lamellipodia formation) at the expense of VASP and Mena interactions (adhesion maturation and filopodia formation). This improved understanding of cytoskeletal regulation in mammalian neural crest migration has general implications for neural crest anomalies and cancer.

Development of an individual helmet orthosis for infants based on a 3D scan.

An early childhood skull deformity can have long-term health and aesthetic consequences for the growing toddler. Individual helmet therapy aims at a healthy growth of the skull shape, although not every helmet shape guarantees an optimal result. To ensure an optimal fit, a scanning procedure based on a hand-held surface scanner was evaluated.The new helmet orthosis has an inner layer adapted to the shape of the head, which can be exchanged depending on the growth stage without changing the outer layer.In collaboration with surgeons and engineers, a new helmet orthosis concept was developed that is intended to offer improvements in wearing comfort, overall weight, fit and user-friendliness compared to conventional systems. In the course of the development process and in constant exchange with parents, a multi-layer helmet system with generous perforations was created using additive manufacturing processes. The new helmet shape promises easier handling, especially through the closure system.The helmet shape developed in this study is of high quality, especially in terms of fitting accuracy. Unpleasant perspiration is significantly reduced. The integration of the closure as a direct component of the helmet represents a secure closure option.

Association of medial collateral ligament complex injuries with anterior cruciate ligament ruptures based on posterolateral tibial plateau injuries.

BACKGROUND: The combined injury of the medial collateral ligament complex and the anterior cruciate ligament (ACL) is the most common two ligament injury of the knee. Additional injuries to the medial capsuloligamentous structures are associated with rotational instability and a high failure rate of ACL reconstruction. The study aimed to analyze the specific pattern of medial injuries and their associated risk factors, with the goal of enabling early diagnosis and initiating appropriate therapeutic interventions, if necessary. RESULTS: Between January 2017 and December 2018, 151 patients with acute ACL ruptures with a mean age of 32 ± 12 years were included in this study. The MRIs performed during the acute phase were analyzed by four independent investigators-two radiologists and two orthopedic surgeons. The trauma impact on the posterolateral tibial plateau and associated injuries to the medial complex (POL, dMCL, and sMCL) were examined and revealed an injury to the medial collateral ligament complex in 34.4% of the patients. The dMCL was the most frequently injured structure (92.2%). A dMCL injury was significantly associated with an increase in trauma severity at the posterolateral tibial plateau (p < 0.02) and additional injuries to the sMCL (OR 4.702, 95% CL 1.3-133.3, p = 0.03) and POL (OR 20.818, 95% CL 5.9-84.4, p < 0.0001). Isolated injuries to the sMCL were not observed. Significant risk factors for acquiring an sMCL injury were age (p < 0.01) and injury to the lateral meniscus (p < 0.01). CONCLUSION: In about one-third of acute ACL ruptures the medial collateral ligament complex is also injured. This might be associated with an increased knee laxity as well as anteromedial rotational instability. Also, this might be associated with an increased risk for failure of revision ACL reconstruction. In addition, we show risk factors and predictors that point to an injury of medial structures and facilitate their diagnosis. This should help physicians and surgeons to precisely diagnose and to assess its scope in order to initiate proper therapies. With this in mind, we would like to draw attention to a frequently occurring combination injury, the so-called "unlucky triad" (ACL, MCL, and lateral meniscus). Level of evidence Level III Retrospective cohort study.

PPP2R1A regulates migration persistence through the NHSL1-containing WAVE Shell Complex.

The RAC1-WAVE-Arp2/3 signaling pathway generates branched actin networks that power lamellipodium protrusion of migrating cells. Feedback is thought to control protrusion lifetime and migration persistence, but its molecular circuitry remains elusive. Here, we identify PPP2R1A by proteomics as a protein differentially associated with the WAVE complex subunit ABI1 when RAC1 is activated and downstream generation of branched actin is blocked. PPP2R1A is found to associate at the lamellipodial edge with an alternative form of WAVE complex, the WAVE Shell Complex, that contains NHSL1 instead of the Arp2/3 activating subunit WAVE, as in the canonical WAVE Regulatory Complex. PPP2R1A is required for persistence in random and directed migration assays and for RAC1-dependent actin polymerization in cell extracts. PPP2R1A requirement is abolished by NHSL1 depletion. PPP2R1A mutations found in tumors impair WAVE Shell Complex binding and migration regulation, suggesting that the coupling of PPP2R1A to the WAVE Shell Complex is essential to its function.

Cerebrospinal Fluid Protein Concentrations in Hydrocephalus.

CSF protein levels are altered in neurological disorders, such as hydrocephalus of different etiologies. In this retrospective observational study, we analyzed cerebrospinal fluid (CSF) samples in hydrocephalic diseases such as aqueductal stenosis (AQS, n = 27), normal pressure hydrocephalus (NPH, n = 24), hydrocephalus communicans (commHC, n = 25) and idiopathic intracranial hypertension (IIH)/pseudotumor cerebri (PC, n = 7) in comparison with neurological patients without hydrocephalic configuration (control, n = 95). CSF was obtained through CSF diversion procedures and lumbar punction and analyzed for protein concentrations according to the institution's laboratory standards. We found significantly decreased CSF protein levels in patients suffering from AQS (0.13 mg/dL [0.1-0.16 mg/dL] p = 2.28 × 10-8) and from PC (0.18 mg/dL [0.12-0.24 mg/dL] p = 0.01) compared with controls (0.34 mg/dL [0.33-0.35 mg/dL]). Protein levels were not altered in patients suffering from commHC and NPH compared with neurologically healthy individuals. We propose that a decrease in CSF protein levels is part of an active counterregulatory mechanism to lower CSF volume and, subsequently, intracranial pressure in specific diseases. Research regarding said mechanism and more specific proteomic research on a cellular level must still be performed to prove this hypothesis. Differences in protein levels between different diseases point to different etiologies and mechanisms in different hydrocephalic pathologies.

Evaluation of Globe Position Asymmetry in Endocrine Orbitopathy Patients and a Control Group - A Computed Tomography-Based 3D Cephalometric Analysis.

Background: Previous studies have shown that patients suffering from endocrine orbitopathy (EO) seem to present with profound asymmetry in proptosis. As asymmetry might pose a major problem in planning decompression surgery, information on the amount of variation between sides and a concise evaluation method should be available. Therefore, a study based on a concise 3D cephalometric analysis was conceived to evaluate globe position. Methods: A 3D-cephalometric analysis was performed on computed tomography (CT) data from 52 orbitopathy and 54 control data sets. Using 36 anatomic landmarks, 33 distances were evaluated to measure sagittal, vertical, and horizontal globe position. Results: EO patients presented with marked exophthalmos and statistically significant asymmetry. Depending on the 2 measured distances, 38% and 42%, respectively, presented sagittal asymmetry of >2 mm, and 12% and 13%, respectively, presented with sagittal asymmetry >4mm. No such asymmetry was seen in the control group. Furthermore, EO patients showed a larger interglobe distance due to lateral globe position. Marked asymmetry correlated with male sex. Proptosis measured to the deep bony orbit correlated with values measured to the orbital aperture or with constructed Hertel values. Conclusions: Use of 3D cephalometry and CT-based analysis confirmed findings from previous clinical studies on profound sagittal asymmetry in EO. Endocrine orbitopathy leads to a sagittal-lateral globe displacement that is even more pronounced in the current study than in earlier investigations. Concerning surgical therapy, presurgical asymmetry, especially if profound, has to be considered to achieve an esthetic symmetrical outcome. Use of 3D orbital analysis is an appropriate method to describe globe position beyond clinical measurements.

[Anterior plate osteosynthesis for multifragmentary patella fracture with additive stabilization of the distal pole using suture cerclage]. / Anteriore Plattenosteosynthese bei mehrfragmentärer Patellafraktur mit additiver Sicherung des distalen Pols mittels Faden-Cerclage.

OPERATION GOAL: The aims of the surgical treatment are the anatomical reduction of the articular surface and stabilization of a multifragmentary patella fracture with a distal pole fragment using plate osteosynthesis and additive suture tape cerclage to secure the distal fragment. INDICATION: Demonstration of the surgical procedure for a multifragmentary patella fracture in the knee joint of a male cadaver. SURGICAL TECHNIQUE: Start with a median prepatellar skin incision and splitting of the bursa and surrounding fascia. Lateral arthrotomy with proximal and distal extension for complete eversion and articular exposure of the multifragmentary fracture. The fracture is then reduced from the articular side using temporary K­wire fixation and reduction clamps, followed by screw osteosynthesis of the large fragments (e.g., distal and proximal poles). After selection of the plate it is fixed with locking screws. In addition, a suture cerclage according to Krakow and/or McLaughlin is applied distally and transosseously through the tibial tuberosity and proximally through the quadriceps tendon. The knotting of the McLaughlin suture cerclage should be done in 90° flexion of the knee joint. POSTOPERATIVE TREATMENT: Functional postoperative treatment with hard shell orthesis with movement limitation (30°, 60° and 90° for 2 weeks each) and partial weight bearing of 15-20 kg for 6 weeks is recommended. Full weight-bearing is only allowed in full extension. EVIDENCE: Plate osteosynthesis is biomechanically superior in comparison to the widely used tension band osteosynthesis. In multifragmentary fractures, additional augmentation with a suture tape cerclage seems to be appropriate. Due to the lack of study results there is currently no clinical evidence for this.

Real-time MRI: a new tool of radiologic imaging in small children.

Real-time MRI (rt-MRI) in children is a new imaging technique that combines the advantages of US - at frame rates of up to 50 images per second - with the quality and features of MRI. Although still subject of research, it has become a standard tool in the diagnostic portfolio of two pediatric radiology departments in Germany. Based on ultrashort acquisition times, any detrimental effects of macroscopic movements of the child and the physiological movements of the organs are negligible. Especially in pediatric brain imaging, rt-MRI has already proven its value. With suitable indications, rt-MRI can reduce anesthesia and sedation examinations in children below 6 years of age by 40% due to its very short examination time and its robustness to motion. There is a high level of acceptance among parents and referrers when diagnostic possibilities and limitations are communicated correctly. CONCLUSION: Completely new diagnostic possibilities arise in the imaging of the moving lung, the beating heart, joint movements, and speaking and swallowing, as demonstrated in this video-backed review. WHAT IS KNOWN: • MRI in moving children has been burdened with severe artifacts. • Gross motion usually has to be handled by sedation and periodic motion of the heart and lungs has to be compensated with time-consuming techniques until now. WHAT IS NEW: • Real-time MRI allows image acquisition with up to 50 frames per second similar to ultrasound frame rate. • Real-time MRI proofs to be very promising for imaging children, reducing examination time and sedation rate drastically.

Comparison of Onlay Anchor Fixation Versus Transosseous Fixation for Lateral Extra-articular Tenodesis During Revision ACL Reconstruction.

Background: There is evidence on the clinical effectiveness of the Lemaire technique for lateral extra-articular tenodesis (LET) in patients undergoing revision anterior cruciate ligament reconstruction (ACLR), but the best fixation technique is unknown. Purpose: To compare the clinical outcomes of 2 fixation techniques after revision ACLR: (1) onlay anchor fixation, which would avoid tunnel conflict and physis injury, and (2) transosseous tightening and interference screw fixation. Pain at the area of LET fixation was also assessed. Study Design: Cohort study; Level of evidence, 3. Methods: This was a retrospective 2-center study of patients with first-time revision ACLR and either LET with anchor fixation (aLET) with a 2.4-mm suture anchor or LET with transosseous fixation (tLET). Outcomes at minimum 12-month follow-up were assessed with the International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, visual analog scale for pain at the LET fixation area, Tegner score, and anterior tibial translation (ATT). A subgroup analysis within the aLET group investigated passing the graft over or under the lateral collateral ligament (LCL). Results: In total, 52 patients were included (26 patients in each group); the mean ± SD follow-up was 13.7 ± 3.4 months. No statistically significant differences were detected between the groups with respect to patient-reported outcome scores, clinical examination, or instrumented testing (side-to-side difference in ATT at 30° of flexion; aLET, 1.5 ± 2.5 mm; tLET, 1.6 ± 1.7 mm). Clinical failure was detected in 1 patient with aLET and none with tLET. Subgroup analysis revealed a small, nonsignificant flexion deficit in knees in which the iliotibial band strand was passed under (n = 42) or over (n = 10) the LCL. No clinically relevant tenderness was detected at the area of LET fixation in any group (aLET, 0.6 ± 1.3; tLET, 0.9 ± 1.7; over the LCL, 0.2 ± 0.6; under the LCL, 0.9 ± 1.6). Conclusion: Onlay anchor fixation and transosseous fixation of the LET were equivalent with respect to outcome scores and instrumented ATT testing. Clinically, there were minor differences in passage of the LET graft over or under the LCL.

The Plant Leaf: A Biomimetic Resource for Multifunctional and Economic Design.

As organs of photosynthesis, leaves are of vital importance for plants and a source of inspiration for biomimetic developments. Leaves are composed of interconnected functional elements that evolved in concert under high selective pressure, directed toward strategies for improving productivity with limited resources. In this paper, selected basic components of the leaf are described together with biomimetic examples derived from them. The epidermis (the "skin" of leaves) protects the leaf from uncontrolled desiccation and carries functional surface structures such as wax crystals and hairs. The epidermis is pierced by micropore apparatuses, stomata, which allow for regulated gas exchange. Photosynthesis takes place in the internal leaf tissue, while the venation system supplies the leaf with water and nutrients and exports the products of photosynthesis. Identifying the selective forces as well as functional limitations of the single components requires understanding the leaf as an integrated system that was shaped by evolution to maximize carbon gain from limited resource availability. These economic aspects of leaf function manifest themselves as trade-off solutions. Biomimetics is expected to benefit from a more holistic perspective on adaptive strategies and functional contexts of leaf structures.

Craniofacial dysmorphology in Down syndrome is caused by increased dosage of Dyrk1a and at least three other genes.

Down syndrome (DS), trisomy of human chromosome 21 (Hsa21), occurs in 1 in 800 live births and is the most common human aneuploidy. DS results in multiple phenotypes, including craniofacial dysmorphology, which is characterised by midfacial hypoplasia, brachycephaly and micrognathia. The genetic and developmental causes of this are poorly understood. Using morphometric analysis of the Dp1Tyb mouse model of DS and an associated mouse genetic mapping panel, we demonstrate that four Hsa21-orthologous regions of mouse chromosome 16 contain dosage-sensitive genes that cause the DS craniofacial phenotype, and identify one of these causative genes as Dyrk1a. We show that the earliest and most severe defects in Dp1Tyb skulls are in bones of neural crest (NC) origin, and that mineralisation of the Dp1Tyb skull base synchondroses is aberrant. Furthermore, we show that increased dosage of Dyrk1a results in decreased NC cell proliferation and a decrease in size and cellularity of the NC-derived frontal bone primordia. Thus, DS craniofacial dysmorphology is caused by an increased dosage of Dyrk1a and at least three other genes.