Gender-specific factors influencing the glenoid version and reference values for it.

BACKGROUND: Glenoid version is an important factor in the evaluation of shoulder stability and shoulder pathologies. However, there are neither established reference values nor known factors that influence the glenoid version, even though valid reference values are needed for diagnostic and orthopaedic surgery like corrective osteotomy and total or reverse shoulder arthroplasty (TSA/RSA). The aim of our population-based study was to identify factors influencing the glenoid version and to establish reference values from a large-scale population cohort. RESULTS: Our study explored the glenoid versions in a large sample representing the general adult population. We investigated 3004 participants in the population-based Study of Health in Pomerania (SHIP). Glenoid version was measured for both shoulders via magnetic resonance imaging (MRI). Associations with the glenoid version were calculated for sex, age, body height, body weight and BMI. The reference values for glenoid version in the central European population range between -9° and 7.5°, while multiple factors are associated with the glenoid version. CONCLUSION: To achieve a reliable interpretation prior to orthopaedic surgery, sex- and age-adjusted reference values are proposed.

Reference values and influencing factors of the glenohumeral subluxation index: a study on 3004 participants.

BACKGROUND: The primary objective of this study was to examine the glenohumeral subluxation index (GHSI) in a large general population cohort and to define reference values. Glenohumeral subluxation is important in the development and prediction of pathological states of the shoulder joint and in total shoulder arthroplasty. Therefore, another objective was to examine the influence of age, sex, body mass index, and body height and weight on GHSI. METHODS: GHSI according to Walch was measured on bilateral magnetic resonance imaging of 3004 participants of the Study of Health in Pomerania (SHIP, aged 21-90 years). SHIP drew a sample of the adult general population of Pomerania (Northeastern Germany). Reference values for GHSI were assessed by quantile regression models. Associations of sex, age, and anthropometric markers with the GHSI were calculated by linear regression models. RESULTS: A reference range between 42% and 55% for men with a mean of 49% ± 4% was defined, while the upper reference limit for women was 1% higher (mean, 50% ± 4%). Age was inversely associated with the GHSI in males (P < 0.001), while no significant association in females was observed (P = .625). Body weight and body mass index were positively associated (P < .001) without effect modification by sex. Heavy mechanical oscillations on the upper extremity showed no significant association with GHSI (P = .268). CONCLUSION: The reference values for GHSI were expanded to a range of 42%-57% on magnetic resonance imaging. Several associations between GHSI and anthropometric properties are present. According to these associations, adjusted formulas are provided to enable individual, patient-specific diagnostics and therapy. Nevertheless, the clinical picture cannot be neglected.

Next step trauma and orthopaedic surgery: integration of augmented reality for reduction and nail implantation of tibial fractures.

INTRODUCTION: There is a tremendous scope of hardware and software development going on in augmented reality (AR), also in trauma and orthopaedic surgery. However, there are only a few systems available for intra-operative 3D imaging and guidance, most of them rely on peri- and intra-operative X-ray imaging. Especially in complex situations such as pelvic surgery or multifragmentary multilevel fractures, intra-operative 3D imaging and implant tracking systems have proven to be of great advantage for the outcome of the surgery and can help reduce X-ray exposure, at least for the surgical team (Ochs et al. in Injury 41:1297 1305, 2010). Yet, the current systems do not provide the ability to have a dynamic live view from the perspective of the surgeon. Our study describes a prototype AR-based system for live tracking which does not rely on X-rays. MATERIALS AND METHODS: A protype live-view intra-operative guidance system using an AR head-mounted device (HMD) was developed and tested on the implantation of a medullary nail in a tibia fracture model. Software algorithms that allow live view and tracking of the implant, fracture fragments and soft tissue without the intra-operative use of X-rays were derived. RESULTS: The implantation of a medullar tibia nail is possible while only relying on AR-guidance and live view without the intra-operative use of X-rays. CONCLUSIONS: The current paper describes a feasibility study with a prototype of an intra-operative dynamic live tracking and imaging system that does not require intra-operative use of X-rays and dynamically adjust to the perspective of the surgeons due to an AR HMD. To our knowledge, the current literature does not describe any similar systems. This could be the next step in surgical imaging and education and a promising way to improve patient care.

Substantial decrease in paediatric lower extremity fracture rates in German hospitals in 2017 compared with 2002: an epidemiological study.

BACKGROUND: There are no recent studies on the frequency of paediatric lower extremity fractures in Germany. The aims of this study were to report fracture rates of paediatric lower extremity fractures treated in German hospitals in 2002 and 2017 and to detect changes over time as well as to evaluate the gender and age distribution for each fracture location. METHODS: Data from the German National Hospital Discharge Registry, which covers over 99% of all German hospitals, were used for this study. The absolute frequencies and incidence of lower extremity fractures as well as age at the time of fracture and gender were included in the data. The population was subdivided into four age groups: 0-4, 5-9, 10-14, and 15-19 years. The boy: girl ratio (BGR) for all fracture locations was calculated by dividing the absolute frequency of boys by that of girls. The fracture incidence in 2017 was compared with 2002 by calculating the incidence rate ratio (IRR). RESULTS: The total number of fractures decreased by 39.9% from 2002 to 2017. The most common fracture locations in 2002 were femoral shaft, tibial shaft, distal tibia, and lateral and medial malleolus; the absolute number of all these fractures was lower in 2017 than in 2002 in all age groups. The incidence of hip and thigh fractures, knee and lower leg fractures, and foot fractures decreased by 39.0, 41.1, and 33.3%. Proximal tibial fractures increased both in absolute numbers and in incidence in the age groups 0-4, 10-14, and 15-19 years (IRR ≥ 1.1). The overall BGR was 2.3 in 2002 and 2.0 in 2017, indicating that the number of girls relative to that of boys who suffered a lower extremity fracture was higher in 2017 than in 2002. Furthermore, the BGR of all fracture locations increased with age in both years. CONCLUSIONS: The number of paediatric lower extremity fractures treated in German hospitals in 2017 was significantly lower than that in 2002. However, the fracture frequency in girls decreased to a lesser extent than that in boys. The incidence of proximal tibial fractures increased.

Change in paediatric upper extremity fracture incidences in German hospitals from 2002 to 2017: an epidemiological study.

INTRODUCTION: Recent studies investigating the frequency of paediatric fractures in Germany are not available. The primary aim of this study was to report frequencies of the most common paediatric upper extremity fractures treated in German hospitals in 2002 and 2017 and to detect changes over time. METHODS: This study used inpatient data from the German National Hospital Discharge Registry. Absolute frequencies and incidences of the following fracture localisations were analysed: clavicle, proximal humerus, humerus shaft, distal humerus, ulna shaft, radius shaft, forearm shaft, distal radius, and distal forearm. Four age groups were formed: 0-4, 5-9, 10-14, and 15-19 years. The boy-girl ratio (BGR) was calculated for all fracture localisations for both years, respectively. Incidence rate ratios (IRRs) were calculated to compare fracture incidences between 2002 and 2017. RESULTS: The absolute number of the nine fracture localisations together decreased from 38,480 in 2002 to 35,128 in 2017. The overall BGR was 2.0 in both years. The BGR increased with increasing patient age. The incidence of clavicle fractures increased from 2002 to 2017 (IRR ≥ 1.72), while that of humerus fractures (proximal, shaft, and distal) remained the same or decreased (IRR ≤ 1.00) within all age groups. The incidence of isolated ulna or radius shaft fractures increased slightly or remained the same in the two lower age groups (IRR ≥ 1.00), while it decreased in the two higher age groups (IRR ≤ 0.80). Furthermore, complete forearm fractures were more frequent in the 0-4, 5-9, and 10-14 year age groups (IRR ≥ 1.44) in 2017 compared to 2002. The incidence of distal radius und forearm fractures changed only slightly. CONCLUSIONS: The absolute number of paediatric upper extremity fractures decreased from 2002 to 2017, while the incidence of in-hospital treatment of clavicle and forearm fractures increased significantly, indicating a trend towards operative treatment.

Periprosthetic tibial fractures in total knee arthroplasty - an outcome analysis of a challenging and underreported surgical issue.

BACKGROUND: Periprosthetic fractures after total knee arthroplasty (TKA) are an increasing problem and challenging to treat. The tibial side is commonly less affected than the femoral side wherefore few studies and case reports are available. The aim of this study was to analyze the outcome of periprosthetic tibial fractures and compare our data with current literature. METHODS: All periprosthetic tibial TKA fractures that were treated at our Level 1 Trauma Center between 2011 and 2015 were included and analyzed consecutively. The Felix classification was used to assess the fracture type and evaluation included the radiological and clinical outcome (Knee Society Score/KSS, Oxford Knee Score/OKS). RESULTS: From a total of 50 periprosthetic TKA fractures, 9 cases (7 female, 2 male; 2 cruciate retaining, 7 constrained TKAs) involving the tibial side were identified. The mean age in this group was 77 (65-85) years with a follow-up rate of 67% after a mean of 22 (0-36) months. The Felix classification showed type IB (n = 1), type IIB (n = 2), type IIIA (n = 4) and type IIIB (n = 2) and surgical intervention included ORIF (n = 6), revision arthroplasty (n = 1), arthrodesis (n = 1) and amputation (n = 1). The rate of adverse events and revision was 55.6% including impaired wound healing, infection and re-fracture respectively peri-implant fracture. Main revision surgery included soft tissue surgery, arthrodesis, amputation and re-osteosynthesis. The clinical outcome showed a mean OKS of 29 (19-39) points and a functional/knee KSS of 53 (40-70)/41 (17-72) points. Radiological analyses showed 4 cases of malalignment after reduction and plate fixation. CONCLUSIONS: Periprosthetic tibial fractures predominantly affect elderly patients with a reduced bone quality and reveal a high complication rate. Careful operative planning with individual solutions respecting the individual patient condition is crucial. If ORIF with a plate is considered, restoration of the correct alignment and careful soft tissue management including minimal invasive procedures seem important factors for the postoperative outcome.

Computer-assisted navigation is beneficial both in primary and revision surgery with modular rotating-hinge knee arthroplasty.

PURPOSE: The objective of the present study was to explore the effect of navigation on the reconstruction of the mechanical leg axis, implant positioning and the restoration of the joint line in hinged knee arthroplasty in vivo. We present the first 1- to 3-year clinical and radiological results following computer-navigated implantation of the EnduRo modular rotating-hinge knee arthroplasty system (Aesculap AG, Tuttlingen, Germany) as a primary or revision implant. METHODS: Thirty-one patients were analysed retrospectively. Indication was revision surgery in 18 patients and complex primary surgery in 13. The clinical and radiological results of 31 patients with a minimum follow-up of 12 months (mean 22.2 ± 6.2 months) were recorded. Age at follow-up was 55.2 ± 9.9 years. RESULTS: The absolute varus-valgus deviation from the neutral mechanical leg axis was determined at 5.1° ± 5.1° preoperatively and 2.1° ± 1.4° postoperatively. No intraoperative complications or problems with the navigation system were observed. At latest follow-up, no component loosening was detected. Based on the Knee Society Score, a knee score of 64.9 ± 17.7 points and a function score of 67.2 ± 27.3 points were achieved. CONCLUSIONS: Encouraging short-term clinical and radiological results with the computer-navigated implantation of the modular rotating-hinge EnduRo knee arthroplasty system were found in both primary and revision surgery. The navigation facilitated the reconstruction of the leg axis, implant positioning and the restoration of the joint line. LEVEL OF EVIDENCE: IV.

Virtual mapping of 260 three-dimensional hemipelvises to analyse gender-specific differences in minimally invasive retrograde lag screw placement in the posterior acetabular column using the anterior pelvic and midsagittal plane as reference.

BACKGROUND: Due to complex pelvic geometry, percutaneous screw placement in the posterior acetabular column can pose a major challenge even for experienced surgeons. METHODS: The present study examined the preformed bone stock of the posterior acetabular column in 260 hemipelvises. Retrograde posterior column screws were virtually implanted using iPlan CMF (BrainLAB AG, Feldkirchen, Germany); maximal implant length, maximal implant diameter and angles between the screw trajectories and the reference planes anterior pelvic plane as well as the midsagittal plane were assessed for gender-specific differences. RESULTS: The virtual analysis of the preformed bone stock column showed two constrictions of crucial clinical importance. These were located 49.6 ± 3.4 (41.0-60.2) mm (inferior margin of acetabulum) and 77.0 ± 5.6 (66.5-95.3) mm (centre of acetabulum) from the entry point of the implant in men and respectively 43.7 ± 2.3 (38.3-49.3) mm as well as 71.2 ± 3.5 (63.5-79.99) mm in women (men vs. women: p < 0.001). The entry point of the retrograde posterior column screw was located dorsal from the transition of the lower margin of the ischial tuberosity to ramus inferior pointing to the medial margin of the ischial tuberosity. In female patients, the entry point was located significantly closer to the medial margin of the ischial tuberosity. However, 7.3 mm screws can generally be used in men and women. The angle between the screw trajectory and the anterior pelvic plane in sagittal section was 14.0 ± 4.9 (2.5-28.6) °, the angle between the screw trajectory and the midsagittal plane in axial section was 31.1 ± 12.8 (1.5-77.9) ° and the angle between the screw trajectory and the midsagittal plane in coronal section was 8.4 ± 3.8 (1.5-20.0) °. For all angles, significant gender-specific differences were found (p < 0.001). CONCLUSION: Therefore, the anterior pelvic plane as well as the midsagittal plane can facilitate intraoperative orientation for retrograde posterior column screw placement considering gender-specific differences in preformed bone corridor, implant length as well as angles formed between screw trajectory and these reference planes.

Hip Revision Arthroplasty of Periprosthetic Fractures Vancouver B2 and B3 with a Modular Revision Stem: Short-Term Results and Review of Literature.

BACKGROUND: Periprosthetic fractures Vancouver type B2/B3 after total hip arthroplasty (THA) is a challenging entity with increasing numbers. Limited data are available for this type of fracture treated with modular stems. Therefore, this study evaluated the outcome of Vancouver type B2/B3 fractures treated with a modular hip revision stem using a subproximal/distal anchorage and compared it to the current literature. MATERIALS AND METHODS: A consecutive series of periprosthetic Vancouver type B2/B3 fractures treated with a modular revision stem was retrospectively (2013 - 2016) evaluated. Assessment included the clinical (HHS, pain, ROM) as well as the radiological outcome (subsidence, loosening, facture healing). In adddition, the surgical technique is described in detail and results are compared with the current literature. RESULTS: A total of 18 patients (female/male 12/6) with Vancouver B2/B3 (n = 12/6) fractures with a mean age of 75.5 (60 - 89) years were included. The revision stem was inserted via a modified transgluteal approach (n = 16) or classical transfemoral approach (n = 2). The mean follow-up was 18.5 months, with a mean Harris Hip Score of 72.5 ± 18.7 (35.0 - 99.0) points. The fracture healing rate was 94.4% (n = 17) with osseous integration according to Engh in all cases. Dislocations of the greater trochanter were recorded in seven patients (38.9%). According to Beals and Towers, all results were rated excellent or good. No implant-related failure or relevant subsidence during this time was observed. Major complications were observed in five patients with two periprosthetic joint infections and two cases of major revision surgery. CONCLUSION: This study assessing Vancouver B2/3 fractures shows reproducible, good, short-term results in terms of subsidence and clinical functional outcome by the use of a modular revision stem. The transfemoral approach together with the modular stem allows for a stable fixation and good fracture healing. However, our data and review of the literature also documents the difficulties and higher complication rate associated with Vancouver B2/3 fractures.

High complication rate after biplanar open wedge high tibial osteotomy stabilized with a new spacer plate (Position HTO plate) without bone substitute.

PURPOSE: We performed a prospective clinical and radiographic evaluation after open wedge high tibial osteotomy (HTO) using the new Position HTO plate (Aesculap, Tuttlingen, Germany) without bone transplantation. METHODS: Thirty-five open wedge HTOs with the Position HTO plate were performed without bone wedges. The mean patient age was 44.6 ± 9.2 years at the time of osteotomy, which was planned with mediCAD II software (Hectec, Niederviehbach, Germany). The Hospital for Special Surgery score, Lysholm-Gillquist score, Tegner activity level, and International Knee Documentation Committee subjective score were used for clinical assessment. We evaluated radiographs obtained preoperatively and at 2, 6, and 12 months postoperatively using full-weight-bearing anteroposterior whole-leg views and anteroposterior and lateral views of the knee. For statistical analyses, JMP 8.0.1 (SAS, Cary, NC) was used. RESULTS: We observed an overall complication rate of 34% and a plate-related complication rate of 23%. Plate-related complications included loss of correction, fracture of the tibial plateau, screw failure, malunion, and fracture of the lateral cortical bone. A significant difference in the mechanical tibiofemoral angle of -1.3° ± 1.4° (P < .001) was found between the follow-up at 2 and 6 months. The mean Hospital for Special Surgery score was 74.8 ± 11.7 preoperatively, and it increased to 87.8 ± 11.0 (P < .001). The mean score on the Lysholm-Gillquist knee functional scoring scale was 55.5 ± 21.7 preoperatively, and it improved to 73.0 ± 23.9 (P < .001). The Tegner activity level was 2.6 ± 0.9 preoperatively, and it improved significantly at final follow-up to 3.7 ± 1.8 (P < .02). The International Knee Documentation Committee subjective score was 43.0 ± 14.9 preoperatively, and it increased to 66.1 ± 21 (P < .001). CONCLUSIONS: We have shown a high plate-related complication rate and a significant loss of correction between 2 and 6 months of follow-up after open wedge HTO using the new Position HTO plate without bone wedges. The preoperatively planned mechanical tibiofemoral angle was not achieved. Despite these complications, the clinical outcome improved significantly. The Position HTO plate cannot be recommended with the presented technique. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

[Fractures of the Distal Radius]. / Frakturen des distalen Radius.

The fracture of the distal radius is the most common human fracture. The optimal management of this injury requires extensive knowledge and skills regarding closed and open reposition maneuvers, plastering and various surgical osteosynthesis techniques. Typical as well as rare accompanying injuries must be recognized and included in the treatment regimen.

Matrix-associated autologous chondrocyte implantation with autologous bone grafting of osteochondral lesions of the talus in adolescents: patient-reported outcomes with a median follow-up of 6 years.

BACKGROUND: This study presents patient-reported outcome measures after combined matrix-associated autologous chondrocyte implantation and autologous bone grafting in high-stage osteochondral lesions of the talus in adolescents. METHODS: A total of 12 adolescent patients (13 ankles) received matrix-associated autologous chondrocyte implantation and autologous bone grafting for a solitary osteochondral lesion of the talus at a single centre. The Foot and Ankle Outcome Score and Foot and Ankle Ability Measure were defined as outcome measures (median follow-up 80 months [range 22-107 months]). Pre- and postoperative ankle radiographs were evaluated according to the van Dijk ankle osteoarthritis scale. RESULTS: The study population consisted of four male and nine female cases (mean age at the time of surgery, 17.7 ± 2.1 years). Eight lesions were classified as traumatic and five as idiopathic. Twelve lesions were located medial vs one lateral in the coronal plane and all central in the sagittal plane. The median lesion size and depth were 1.3 cm2 (range 0.9-3.2 cm2) and 5 mm (range 5-9 mm), respectively. There were no perioperative complications in any of the cases. In 9 cases patient-reported outcome measures were available. The results of the Foot and Ankle Outcome Score subscales were symptoms, 70 ± 14; pain, 83 ± 10; activities of daily living, 89 ± 12; sports/recreational activities, 66 ± 26; and quality of life, 51 ± 17. The mean overall Foot and Ankle Outcome Score was 78 ± 13. The results of the Foot and Ankle Ability Measure subscales were activities of daily living, 81 ± 20; function/activities of daily living, 84 ± 13; sports, 65 ± 29; and function/sports, 73 ± 27. According to the function overall subscale of the Foot and Ankle Ability Measure, in two cases, the patients assessed the ankle function as normal, in three as nearly normal, and in three as abnormal (missing data, n = 1). Preoperative van Dijk scale: stage 0 in five cases and stage I in eight cases; postoperative van Dijk scale: stage 0 in four cases, stage I in 9 cases CONCLUSIONS: Patient-reported outcome measures following matrix-associated autologous chondrocyte implantation and autologous bone grafting for high-stage osteochondral lesions of the talus in adolescents show heterogeneous results. Long-term limitations mainly affect sports and recreational activities. Osteochondral lesions of the talus are associated with osteoarthritis, even preoperatively. However, we did not find significant osteoarthritis progression after matrix-associated autologous chondrocyte implantation and autologous bone grafting in the long term.

Comparability of Patient-reported Outcome Measures and Clinical Assessment Tools for Shoulder Function in Patients with Proximal Humeral Fracture. / Vergleichbarkeit subjektiver, durch den Patienten beantworteter Feedbackfragebögen und klinischer Fragebögen zur Beurteilung der Schulterfunktion bei Patienten mit proximaler Humerusfraktur.

BACKGROUND: Patient-reported outcome measures (PROMs) are gaining increasing importance in the context of quality management. Different PROMs and scoring tools are available to assess shoulder function after proximal humeral fracture (PHFx). In Europe, these include the Constant-Murley Score (CS), Neer Score (NS), Oxford Shoulder Score (OSS), University of California at Los Angeles Score (UCLA) and Disabilities of the Arm, Shoulder and Hands Score (DASH). In addition, the health-related quality of life can be assessed by the PROMs Short Form 36 (SF-36) and EuroQol (EQ-5D). Although all these test instruments assess shoulder function, the components to be answered objectively and subjectively vary and thus the possibility of independent assessment. The aim of the present study is to compare the correlation between the results of the different PROMs and the clinical screening tools in patients with PHFx. METHODS: 76 patients who were treated with angular stable plate osteosynthesis for a proximal humeral fracture between 01/2001 and 12/2005 were included in this trial. The outcome was measured with PROMs or clinical scoring tools such as CS, NS, OSS, UCLA, DASH, SF-36 and EQ-5D and a correlation coefficient between those evaluation tools was calculated. In addition, a distinction was made between the two force measurement methods (wrist [HG] vs. deltoid muscle [DM]) for CS. RESULTS: The correlation of the results of CS and NS (HG: r = 0.85; p < 0.001/DM: r = 0.93; p < 0.001), CS and UCLA (HG: r = 0.83; p < 0.001/DM: r = 0.86; p < 0.001), NS and UCLA (r = 0.91; p < 0.001) as well as DASH and OSS (r = 0.88; p < 0.001) was strongly expressed. A good comparability of the results was demonstrated between CS and OSS (HG: r = 0.63; p < 0.001/DM: r = 0.66; p < 0.001) and between CS and DASH (HG: r = 0.62; p < 0.001/DM: r = 0.61; p < 0.001). The correlation of CS (HG/DM) and UCLA with the EQ-5D index was also good. Assessment of the physical components of SF-36 with CS, NS, OSS, UCLA and DASH showed a moderate to good association, while the mental components of SF-36 showed a low correlation (p > 0.05). CONCLUSION: The assessment of shoulder function after proximal humerus fracture showed a very strong correlation within the clinical questionnaires (CS/NS/UCLA) and the PROMs (OSS/DASH). A strong correlation also exists between the clinical questionnaires and the PROMs. There was only a moderate correlation with the EQ-5D. The moderate to strong correlation between the physical components of SF-36, with almost no correlation between the mental components of SF-36, indicates that the quality of life restriction is based on a physical, but not on a mental impairment.

Re-operation rate after surgical treatment of osteochondral lesions of the talus in paediatric and adolescent patients.

BACKGROUND: The aim of this study is to analyse the re-operation rate after surgical treatment of osteochondral lesions of the talus (OCLTs) in children and adolescents. METHODS: Between 2009 and 2019, 27 consecutive patients with a solitary OCLT (10 male, 17 female; mean age 16.9 ± 2.2 years; 8 idiopathic vs. 19 traumatic) received primary operative treatment (arthroscopy + bone marrow stimulation [BMS], n = 8; arthroscopy + retrograde drilling, n = 8; autologous chondrocyte implantation [ACI]/autologous bone grafting, n = 9; arthroscopy + BMS + retrograde drilling; n = 1; flake fixation, n = 1). Seventeen OCLTs were located at the medial and ten at the lateral talus. 'Re-operation' as the outcome measure was evaluated after a median follow-up of 42 months (range 6-117 months). Patients were further subdivided into groups A (re-operation, n = 7) and B (no re-operation, n = 20). Groups A and B were compared with respect to epidemiological, lesion- and therapy-related variables. RESULTS: Seven of 27 patients needed a re-operation (re-operation rate 25.9% after a median interval of 31 months [range 13-61 months]). The following operative techniques were initially used in these seven patients: arthroscopy + BMS n = 2, arthroscopy + retrograde drilling n = 4, ACI + autologous bone grafting n = 1. A comparison of group A with group B revealed different OCLT characteristics between both groups. The intraoperative findings according to the International Cartilage Repair Society (ICRS) classification revealed significantly more advanced cartilage damage in group B than in group A (p = 0.001). CONCLUSIONS: We detected a re-operation rate of 25.9% after primary surgical OCLT treatment. Patients with re-operation had significantly lower ICRS classification stages compared to patients without re-operation.

Differential target gene activation by the Staphylococcus aureus two-component system saeRS.

The saePQRS system of Staphylococcus aureus controls the expression of major virulence factors and encodes a histidine kinase (SaeS), a response regulator (SaeR), a membrane protein (SaeQ), and a lipoprotein (SaeP). The widely used strain Newman is characterized by a single amino acid change in the sensory domain of SaeS (Pro18 in strain Newman [SaeS(P)], compared with Leu18 in other strains [SaeS(L)]). SaeS(P) determines activation of the class I sae target genes (coa, fnbA, eap, sib, efb, fib, sae), which are highly expressed in strain Newman. In contrast, class II target genes (hla, hlb, cap) are not sensitive to the SaeS polymorphism. The SaeS(L) allele (saeS(L)) is dominant over the SaeS(P) allele, as shown by single-copy integration of saePQRS(L) in strain Newman, which results in severe repression of class I target genes. The differential effect on target gene expression is explained by different requirements for SaeR phosphorylation. From an analysis of saeS deletion strains and strains with mutated SaeR phosphorylation sites, we concluded that a high level of SaeR phosphorylation is required for activation of class I target genes. However, a low level of SaeR phosphorylation, which can occur independent of SaeS, is sufficient to activate class II target genes. Using inducible saeRS constructs, we showed that the expression of both types of target genes is independent of the saeRS dosage and that the typical growth phase-dependent gene expression pattern is not driven by SaeRS.

Reliability of the Oswestry-Bristol Classification for trochlear dysplasia: expanded characteristics.

AIMS: The Oswestry-Bristol Classification (OBC) was recently described as an MRI-based classification tool for the femoral trochlear. The authors demonstrated better inter- and intraobserver agreement compared to the Dejour classification. As the OBC could potentially provide a very useful MRI-based grading system for trochlear dysplasia, it was the aim to determine the inter- and intraobserver reliability of the classification system from the perspective of the non-founder. METHODS: Two orthopaedic surgeons independently assessed 50 MRI scans for trochlear dysplasia and classified each according to the OBC. Both observers repeated the assessments after six weeks. The inter- and intraobserver agreement was determined using Cohen's kappa statistic and S-statistic nominal and linear weights. RESULTS: The OBC with grading into four different trochlear forms showed excellent inter- and intraobserver agreement with a mean kappa of 0.78. CONCLUSION: The OBC is a simple MRI-based classification system with high inter- and intraobserver reliability. It could present a useful tool for grading the severity of trochlear dysplasia in daily practice.Cite this article: Bone Joint Open 2020;1-7:355-358.

Factors influencing the complication rate in pediatric supracondylar humerus fractures.

The aim of the study was to identify influencing factors on the complication rate in pediatric supracondylar humerus fractures (PSHF). 22 male and 19 female patients with an extension type PSHF underwent conservative and operative treatment at a single trauma department and were reviewed retrospectively. The complications were assessed and the groups of patients with and without complications were compared according to patient- and therapy-related factors. The overall complication rate was 19.5%. Two patients had a primary and 4 patients a postoperative neurological deficit. One patient developed a pin infection after open reduction and crossed pin fixation. One patient underwent early revision surgery because of insufficient initial reduction after closed reduction and crossed pin fixation. All complications appeared in the surgical treatment group. The appearance of complications was significantly associated with a higher Gartland stage. The median time between trauma and operation was significantly longer in patients without compared to patients with complications. PSHF are associated with a high rate of neurological complications. The Gartland stage and the necessity of surgical treatment are the major influencing factors on the complication rate.

EASY (endoscopic approach to the symphysis): a new minimally invasive approach for the plate osteosynthesis of the symphysis and the anterior pelvic ring-a cadaver study and first clinical results.

BACKGROUND: Minimally invasive surgical approaches to reduce approach-associated morbidity are an interdisciplinary goal in surgery. In principle, the endoscopic approach for the extraperitoneal repair of groin hernias is the minimally invasive variant of the modified Stoppa-approach, which is used for the treatment of pelvic ring injuries in traumatology. METHOD: Anatomical feasibility study regarding the plate osteosynthesis of the anterior pelvic ring via a minimally invasive variant of the modified Stoppa-approach. RESULTS: We present the minimally invasive variant of the modified Stoppa-approach in a human cadaver step by step, both photographically and radiologically. Feasibility of the plate osteosynthesis of the symphysis is presented in a patient with open book injury via the minimally invasive approach using standard laparoscopic instruments. CONCLUSION: The plate osteosynthesis of the anterior pelvic ring via the minimally invasive variant of the modified Stoppa-approach is feasible with existing standard laparoscopic instruments.

[Suturing an Acute ACL Lesion with Dynamic Intraligamentary Stabilisation]. / Die Naht der frischen vorderen Kreuzbandruptur mit dynamischer intraligamentärer Stabilisierung ­ eine Alternative zur vorderen Kreuzbandersatzplastik bei sportlich aktiven jungen Patienten.

BACKGROUND: The established surgical technique for lesion of the anterior cruciate ligament (ACL) is reconstruction with an autologous tendon. However, patients after ACL-replacement have increased osteoarthritis rates. Possible explanations are persistent knee instability and the loss of the ACL's proprioceptive function. Therefore, surgeons have developed an alternative treatment to preserve the ACL by readapting femoral ACL lesions by temporary protective dynamic intraligamentary stabilisation (DIS). INDICATION: The indication includes acute (< 21 days old) ACL injuries of young patients who are active in sport. The rupture should be located in the proximal third of the ACL with a side-to-side interval of more than 5 mm in the antero-posterior tibial translation. METHODS: In this video, a 22-year-old patient with an ACL lesion was operated three weeks after injury. CONCLUSION: Readapting femoral ACL lesions by DIS is an adequate technique to preserve the ACL and to restore knee stability.

Adverse Events in the Treatment of Periprosthetic Fractures Around the Knee - a Clinical and Radiological Outcome Analysis. / Komplikationen in der Behandlung periprothetischer Frakturen bei einliegender Knietotalendoprothese ­ eine klinisch-radiologische Outcome-Analyse.

BACKGROUND: The incidence of periprosthetic fractures associated with total knee arthroplasty (PpFxK) has been reported to be 0.3 - 5.5%. 40% of all cases are related to revision TKA. The most common localisation is the distal femur. Classification is performed according to Rorabeck (RB). RB I - II fractures are usually treated with locked plating and retrograde intramedullary nailing, whereas RB III fractures are an indication for revision arthroplasty using a hinged endoprosthesis. PpFxK of the patella can be classified according to Goldberg and PpFxK of the proximal tibia can be grouped as in Felix. Interprosthetic fractures can be regarded as a special type of PpFx. Due to the increasing numbers of TKA being performed, increasing numbers of adverse events in arthroplasty can be expected. Adverse events in the treatment of PpFxK occur in up to 41% of patients according to the literature and revision is needed in approximately 29% of all cases. Risk factors are age, osteoporosis, infection, malalignment, osteolysis/loosening of the implant and status post revision. PATIENTS: A clinical and radiographic follow-up was performed with 50 patients (14 men, 36 women) treated for PpFxK of the femur, tibia and patella between 2011 and 2015 at the department of arthroplasty at a level 1 trauma center in Europe. RESULTS: The follow-up of all patients was 68%, with an average of 19.1 ± 14.6 (1 - 49) months between PpFxK and clinical follow-up. 16% of the patients were allocated for further treatment or revision surgery from other hospitals. The patients' median age was 78.0 ± 8.8 (55 - 94) years. Most patients were affected by several orthopaedic and internal medical comorbidities. PpFxK classified as RB II were the most common fractures (60%, n = 30). PpFxK usually occurred 5.0 ± 4.8 (0 - 20) years after index TKA (primary or revision TKA), mostly in patients with CR-retaining endoprosthesis, whereas PpFxK according to Felix occurred significantly earlier and mostly in hinged TKAs. Patients achieved on average a mean Oxford Knee Score of 31.1 ± 9.9 (14 - 46) points. The functional Knee Society Score (KSS) was 52.6 ± 24.4 (20 - 100) and the mean KSS was 58.7 ± 26.8 (0 - 99) points (n = 25). Radiographic evaluation of the RB I - II patients showed frontal and sagittal malalignment in 20.6% of all cases after reduction and plate fixation. The overall rate of surgical adverse events was 50%; 44% of all RB patients needed revision surgery. Adverse events comprised non-union, failure of osteosynthesis, infection, wound healing disorders and re-fractures in the RB II and the Felix subgroup. CONCLUSION: PpFxK are severe injuries and are associated with a high rate of adverse events related to treatment. Patients often have a complex background and a history of revision surgery or periprosthetic joint infection. The treatment of PpFxK should therefore take place at a centre with expertise in traumatology as well as in revision arthroplasty. Preoperative infection diagnostic testing as well as adequate imaging (X-rays and CT) are essential. We furthermore advise early evaluation of revision arthroplasty, especially in elderly patients suffering from PpFxK with insufficient bone quality around the TKA and closeness between fracture and TKA. In the case of plate fixation, it is important to give attention to correct reduction - to prevent non-union, loosening of the implant and failure of the osteosynthesis - as well as to consider double plating.