Weight-bearing MRI with a knee flexion angle of 20°: a study on additional MRI investigation modalities to support a more accurate understanding of patellofemoral instability.

BACKGROUND: Diagnosing patellofemoral instability disorders correctly, weight-bearing MRI (WB-MRI) has become an option. Aiming for a best possible accuracy in displaying potentially underlying causes, the named MRI modalities were sporadically even investigated in different knee flexion angles. However, despite confirmed MRI-outcome-differences between WB-MRI and non-WB-MRI, none of the described MRI modalities have so far established themselves. Mainly this is due to an unfeasibility in daily clinical routine in regard to time and economic aspects. Thus, we intended to evaluate an additional but reduced patellofemoral MR-imaging solely in a relevant 20° of knee flexion under WB- and non-WB-MRI conditions. METHODS: Seventy-three subjects with and without patellofemoral instability were investigated under supine as well as under WB-MRI conditions in a 20° of knee flexion angle. Patellofemoral risk indices in the sagittal plane (Insall-Salvati-Index, Caton-Deschamps-Index, Patellotrochlear Index) and the axial plane (Patella tilt of Fulkerson and Sasaki) were detected and compared between the different MRI conditions. Significance, reliability and Cohen's effect size was calculated. RESULTS: Nearly all assessed indices showed significant differences between patients and controls in the different MRI positions. Comparing pairwise, all measured indices failed to show significant differences between the two MRI positions. However, patella tilt angles of the patient group showed an elevation from supine to WB-MRI (14.00 ± 7.54° to 15.97 ± 9.10° and 16.34 ± 7.84° to 18.54 ± 9.43°). Here, Cohen's d showed small to medium effects between supine and WB-MRI. CONCLUSION: In comparison to standard MRI in supine position, axial risk indices seem to be accentuated under WB-MRI and a knee flexion angle of 20°. In particular, symptomatic cases with inconspicuous conventional MRI imaging, additional MRI imaging only in the axial plane in a 20° of knee flexion could be beneficious and useful in clinical daily routine.

Results of a tri-national online survey on the current status of sports injury prevention among members of the German-Speaking Orthopaedic Sports Medicine Society (GOTS).

OBJECTIVES: To assess the current opinions and state of knowledge in primary sports injury prevention among members of the German-Speaking Society for Orthopaedic and Traumatologic Sports Medicine (GOTS). METHODS: On 21 August 2019, a web-based questionnaire was sent to the members of the tri-national society GOTS (Austria, Germany and Switzerland). The survey was online until 21 November 2019 and included twenty-two questions, which were divided into five sections: 1) general importance of prevention (n = 4), 2) specifications of the study population (n = 3), 3) implementation of prevention (n = 8), 4) improvement opportunities in prevention (n = 4) and 5) future research areas (n = 3). RESULTS: A total of 272 participants completed the survey, representing a total survey participation of 17.7 % of all members. The study population consisted of orthopaedic surgeons (55 % with surgical and 21 % with non-operative orientation), medical students (10 %), physical therapists (8 %) and sports scientists (4 %). Ninety-four percent of all participants stated that they considered the importance of sports injury prevention to be "very high" (68 %) or "high" (26 %). However, almost 70 % of all participants stated that they spend less than one hour per week on injury prevention work. The term "prevention" was clearly defined and practicable for only 40 %, understandable but difficult to implement for 51 %, and unclear and difficult to implement for 9 % of the participants. Seventy-two percent of respondents were aware of existing prevention programs such as "Stop-X" or "FIFA 11 +", whereas 28 % of participants were uninformed regarding these programs. CONCLUSIONS: A strong divergence was identified between participants' perception of the importance of sports injury prevention and the existing implementation of preventive measures. Future funding of prevention programs, expansion of research strategies for injury prevention and better financial reimbursement are of utmost importance.

Menthol as an Ergogenic Aid for the Tokyo 2021 Olympic Games: An Expert-Led Consensus Statement Using the Modified Delphi Method.

INTRODUCTION: Menthol topical application and mouth rinsing are ergogenic in hot environments, improving performance and perception, with differing effects on body temperature regulation. Consequently, athletes and federations are beginning to explore the possible benefits to elite sport performance for the Tokyo 2021 Olympics, which will take place in hot (~ 31 °C), humid (70% RH) conditions. There is no clear consensus on safe and effective menthol use for athletes, practitioners, or researchers. The present study addressed this shortfall by producing expert-led consensus recommendations. METHOD: Fourteen contributors were recruited following ethical approval. A three-step modified Delphi method was used for voting on 96 statements generated following literature consultation; 192 statements total (96/96 topical application/mouth rinsing). Round 1 contributors voted to "agree" or "disagree" with statements; 80% agreement was required to accept statements. In round 2, contributors voted to "support" or "change" their round 1 unaccepted statements, with knowledge of the extant voting from round 1. Round 3 contributors met to discuss voting against key remaining statements. RESULTS: Forty-seven statements reached consensus in round 1 (30/17 topical application/rinsing); 14 proved redundant. Six statements reached consensus in round 2 (2/4 topical application/rinsing); 116 statements proved redundant. Nine further statements were agreed in round 3 (6/3 topical application/rinsing) with caveats. DISCUSSION: Consensus was reached on 62 statements in total (38/24 topical application/rinsing), enabling the development of guidance on safe menthol administration, with a view to enhancing performance and perception in the heat without impairing body temperature regulation.

Patient-related outcome measurements after operative and conservative management of traumatic proximal adductor longus avulsion injuries.

PURPOSE: In the rare case of complete proximal adductor longus avulsion injuries, scientific recommendations of surgical or conservative injury management are limited to small case series and reviews of small cohorts about treatment examples. A clear consensus regarding optimal management so far has not been made. Thus, the aim of our study was to investigate patient-related outcome measurements (PROM) after either operatively or conservatively treated patients in order to evaluate and display own decision criteria for one of the two treatment options. METHODS: In this retrospective case control study, two cohorts after MRI-confirmed, isolated, acute proximal adductor longus avulsion injury without concomitant injuries was investigated. Depending on stump retraction (less or more than 2 cm), patients of the particular cohorts had either been treated conservatively or by surgical refixation with suture anchors. All patients were asked to complete different PROM forms (Hip Osteoarthritis Outcome Score (HOS), Modified Harris Hip Score (MHHS)) in order to evaluate the particular procedures outcome. RESULTS: Between July 2015 and July 2018, eighteen avulsion injuries met our inclusion criteria, of which 14 were treated conservatively and operatively in equal parts and could be included into the study. The mean stump retraction of the conservative group was 1.3 cm (SD ± 0.5); patients in the surgical group had a mean stump retraction of 3.0 cm (± 1.5). Irrespective of the treatment option, all patients achieved a maximum score using the MHHS. Also in the HOS subscale respecting all day activities, almost all patients (13/14) achieved a maximum score. Instead, using the HOS subscale respecting sportive activities, one surgically and one conservatively treated patient described little restrictions compared with their pre-injury level. CONCLUSION: Conservative as well as operative treatment leads to very good patient-related outcome measurements if the decision for either of the two treatment options is made upon a stump retraction above or below 2 cm. Smaller restrictions regarding pre-injury level could rather be seen in the conservative instead of the operative group, favouring a more generous perspective for surgical refixation.

Management of giant retinal tears with vitrectomy and perfluorocarbon liquid postoperatively as a short-term tamponade.

PurposeThe purpose of this study was to study outcomes after using perfluorocarbon liquid (PFCL) as a short-term postoperative vitreous substitute in eyes with retinal detachment from giant retinal tears (GRTs).Patients and methodsA retrospective consecutive case series of patients with retinal detachment from GRT, who underwent vitrectomy using PFCL as short-term postoperative retinal tamponade. PFCL was left in the eye for a mean of 6.7 days (range 7-8 days) and then replaced with gas or silicone oil (SO). The anatomical and functional outcomes and postoperative complications are reported.ResultsA total of 30 eyes of 29 patients with a follow-up of 26.8 months (range 9-55 months) were included. GRTs had a mean size of 150° (range 90°-270°) with 46.6% of eyes with a tear of >180°. Intraoperative retinal re-attachment was achieved in all cases. No cases of retinal slippage were recorded. Four eyes (13.3%) had re-detachment and further surgery required. At final review, 27 eyes (90.9%) had attached retinas, while the remaining 9.1% had SO in situ. The visual acuity improved in 70% of eyes with 41% improving at least 2 Snellen lines and 35% with visual acuity of 6/12 or better. Mild anterior uveitis developed in six eyes (20%), which resolved on topical steroids. Glaucoma developed in one eye and was controlled medically.ConclusionOur study supports the safety and efficacy of PFCL as a short-term postoperative tamponade in cases of GRTs. As it reduces retinal slippage, the use of SO as a primary tamponade decreased in significant proportion of cases.

Computation of Rate Constants for Diffusion of Small Ligands to and from Buried Protein Active Sites.

The diffusion of ligands to actives sites of proteins is essential to enzyme catalysis and many cellular signaling processes. In this contribution we review our recently developed methodology for calculation of rate constants for diffusion and binding of small molecules to buried protein active sites. The diffusive dynamics of the ligand obtained from molecular dynamics simulation is coarse grained and described by a Markov state model. Diffusion and binding rate constants are then obtained either from the reactive flux formalism or by fitting the time-dependent population of the Markov state model to a phenomenological rate law. The method is illustrated by applications to diffusion of substrate and inhibitors in [NiFe] hydrogenase, CO-dehydrogenase, and myoglobin. We also discuss a recently developed sensitivity analysis that allows one to identify hot spots in proteins, where mutations are expected to have the strongest effects on ligand diffusion rates.

MRI-associated classification to evaluate the outcome after autologous reconstruction of the medial patellofemoral ligament: a preliminary study.

PURPOSE: Purpose of this study was to establish and validate an MRI-associated classification to graduate postoperative results of MPFL reconstructions. METHODS: 30 autologous MPFL reconstructions of 28 patients were evaluated by two independent raters using MRI. All grafts were assigned to a novel graduation system respecting the graft's anchoring insertions, its MRI signal appearance, continuity and tension and the differentiation relating to the surrounding soft tissue. RESULTS: All grafts could reliably be assigned to one of the subgroups by both raters. 86.6 % of the grafts could be classified A1 or B1, reflecting a correct positioning and a low to intermediate signal intensity. Only one graft had to be classified C3 (malpositioned, elongated). CONCLUSION: We were able to establish and validate an MRI-associated classification to graduate the postoperative outcome after MPFL reconstructions. Foresighted, the presented classification might support further decision making in case of unsatisfying postoperative results.

Radiographic monitoring of the distal insertion of the calcaneofibular ligament in anatomical reconstructions of ankle instabilities: A preliminary cadaveric study.

BACKGROUND: The purpose of the study therefore was to determine radiographic landmarks that support the identification of the insertion site of the distal calcaneofibular ligament (CFL) in anatomic ankle ligament reconstructions. METHODS: In 10 lower limb cadaver specimens the midpoint of the distal CFL insertion was dissected and marked with a nail inserted orthogonally. On a standardized lateral radiograph in neutral ankle position a horizontal tangent was aligned to the deepest visible concavity of the tarsal sinus and one vertical tangent to the farthest posterior convexity of the talus. Additionally, a line was drawn from the radiographically marked distal CFL to the fibular insertion of the CFL to determine the CFL-fibular angle. RESULTS: In relation to the radiographic tangents intersection the mean deviation of the depicted CFL nails was 2.2mm [SD ± 1.1 mm] leading to an angular, circular to slightly oval 6 mm insertion. The scatter-plot of the marked positions convened along a line from the supposed fibular CFL insertion to the intersection in all cases. The mean CFL-fibular angle was 131.7° [SD ± 3.16°]. CONCLUSIONS: Determining a virtual intersection between a horizontal tangent aligned to the deepest visible concavity of the tarsal sinus and one vertical tangent aligned to the farthest posterior convexity of the talus on a standardized lateral radiograph in neutral ankle position supports an anatomic insertion of the distal calcaneofibular ligament most probably.

Need for a roadmap for development of a coordinated national registry programme.

Clinical quality registries are an overlooked and under-funded arm of clinical research in Australia. Registries are databases for patients with a particular disease, or who undergo a procedure, or use a health resource. Registries, where properly funded and universally adopted, have provided substantial benefits to the quality of healthcare and, in some cases, have had demonstrable effect in reducing costs. There is a lack of a coordinated programme for both funding and development of registries in Australia. A coordinated effort is required to address key gaps in registry coverage and ensure registries comply with appropriate technical and operating principles, and target areas where registries can add value to the health system. This will ensure that Australia is competitive with its international peers in this dynamic environment.

[Bone marrow edema and atraumatic necrosis of the femoral head : Therapy]. / Knochenmarködem und atraumatische Femurkopfnekrose : Therapie.

BACKGROUND: An increase in interstitial bony fluid occurs in bone-marrow edema (BME). The exact pathogenetic processes still remain unknown. BME is an unspecific finding that can occur on its own or accompany multiple diseases and pathologies. GOAL: Literature review and presentation of new guidelines. MATERIAL AND METHODS: This is a narrative literature review followed by current advice for the therapy of atraumatic osteonecrosis of the hip, based on the recently published S3-guidelines for this disease. RESULTS AND DISCUSSION: The differentiation of at least 3 different etiologies is proposed (mechanic, reactive and ischemic). Difficult, but important, is the distinction between the mostly painful, but benign entities (BME syndrome, bone bruise) and the progressive pathologies (osteonecrosis, arthritis, CRPS, tumour). Treatment options are dependent on etiology and clinic and can often be symptomatic. Core decompression is the surgical gold standard, leading to immediate pressure relief and therefore reduction in pain. Recently, it was shown that intravenous administration of Iloprost and bisphosphonates are also effective in achieving a reduction of BME and pain, with considerable improvement in the accompanying symptoms. The combination of core decompression and infusion seems to be another possible optimization ofthe therapy, in particular in the treatment of osteonecrosis.

Computer-based quantification of the Achilles tendon thickness in sequential B-mode ultrasound images: a study of feasibility and reliability.

INTRODUCTION: Assessment of the Achilles tendon thickness (ATT) using B-mode ultrasound is a common technique for clinical evaluation of chronic mid-part tendinosis. Currently used image-based assessment is limited by relatively high inter- and intra-observer variability. In this study, it was tested whether a new sequence-based automated assessment of ATT provides more reliable and reproducible results than the standard image-based procedure. MATERIALS AND METHODS: A total of 118 non-operated tendons of 59 healthy subjects (44, range 28-50 years) were analysed using an automated image based as well as a newly developed automated sequence-based method. Correlation and agreement of both methods were evaluated. The root mean square deviation (RMSD) and a Bland-Altman analysis were performed to highlight observer (n = 18 tendons) as well as reader (n = 40 tendons) dependent variabilities of both methods. RESULTS: A strong correlation was found between image and sequence-based ATT assessment (p = 0.92). The Bland-Altman analysis showed a good agreement between both methods (mean difference 0.0018, 95 % CI: -0.046; 0.05). In repetitive examinations, sequence-based analysis showed a significant reduction concerning reader- and observer-dependent variability compared to image-based assessment. The RMSD for repetitive sequence-based measurements was approximately 0.3 mm (compared to 0.6 mm for image-based measurement), respectively. CONCLUSIONS: The study shows sequence-based automated assessment of ATT being clearly superior to the standard image-based procedure. The new method provides a clear reduction of reader as well as observer-dependent variability. Due to the decreased scattering of measurement data sequence-based measurement seems especially valuable for quantification of small tendon thickness changes such as exercise-induced hypertrophy.

[Evidence for treatment of acute syndesmosis injuries in sports]. / Evidenz der Versorgung der akuten Syndesmosenverletzung im Sport.

Injuries of the distal syndesmosis often accompany acute ankle sprains especially in professional team sports. While small partial syndesmosis lesions can often be missed as a consequence of impressive symptoms due to ventrolateral capsuloligamentous injuries, higher grade injuries of the syndesmosis can mostly be diagnosed without any problem. Furthermore, there is a consensus concerning the necessity of operative treatment in significantly unstable situations as well concerning conservative treatment of incomplete partial lesions. Consequently, the greatest challenge regarding diagnostic tools, quantification and optimal therapy arises in the most common form of sport-associated, complete or partial lesions of the distal syndesmosis. This review article summarizes sports-associated injuries of the distal tibiofibular syndesmosis considering the current literature and placing the emphasis on the anatomy, pathobiomechanics, diagnostics and therapy of syndesmosis lesions from an evidence-based viewpoint.

[Current treatment concepts for muscular injuries]. / Aktuelle Behandlungskonzepte bei Muskelverletzungen.

Muscular lesions represent the most common form of sports injury. The four large muscle groups hamstrings, adductors, gastrocnemius and knee extensor muscles are most often affected. Most injuries occur during excentric tension impact. Diagnostics begin with an exact medical history and detailed clinical investigations. Imaging with ultrasound and magnetic resonance imaging (MRI) are important to differentiate between structural lesions and functional disorders and to determine the extent of the injury. Most frequently treatment remains conservative and is oriented to the three phases of the healing process. In most cases (leisure sports) the rest, ice, compression and elevation (RICE) concept with subsequent pain-adapted load increase suffices for a return to sport activities. Infiltration therapy including platelet-rich plasma (PRP) is an additional therapy option but should not be used to accelerate the healing process. Surgical treatment only rarely becomes necessary for treatment of muscular injuries.

ACMG statement on noninvasive prenatal screening for fetal aneuploidy.

Noninvasive assessment of the fetal genome is now possible using next-generation sequencing technologies. The isolation of fetal DNA fragments from maternal circulation in sufficient quantity and sizes, together with proprietary bioinformatics tools, now allows patients the option of noninvasive fetal aneuploidy screening. However, obstetric care providers must become familiar with the advantages and disadvantages of the utilization of this approach as analysis of cell-free fetal DNA moves into clinical practice. Once informed, clinicians can provide efficient pretest and posttest counseling with the goal of avoiding patient harm. It is in the public's best interest that test results contain key elements and that laboratories adhere to established quality control and proficiency testing standards. The analysis of cell-free fetal DNA in maternal circulation for fetal aneuploidy screening is likely the first of major steps toward the eventual application of whole fetal genome/whole fetal exome sequencing.

Trait vs. phylogenetic diversity as predictors of competition and community composition in herbivorous marine amphipods.

Field studies of community assembly patterns increasingly use phylogenetic relatedness as a surrogate for traits. Recent experiments appear to validate this approach by showing effects of correlated trait and phylogenetic distances on coexistence. However, traits governing resource use in animals are often labile. To test whether feeding trait or phylogenetic diversity can predict competition and production in communities of grazing amphipods, we manipulated both types of diversity independently in mesocosms. We found that increasing the feeding trait diversity of the community increased the number of species coexisting, reduced dominance and changed food availability. In contrast, phylogenetic diversity had no effect, suggesting that whatever additional ecological information it represents was not relevant in this context. Although community phylogenetic structure in the field may result from multiple traits with potential for phylogenetic signal, phylogenetic effects on species interactions in controlled experiments may depend on the lability of fewer key traits.