Above-knee amputation shows higher complication and mortality rates in line with lower functional outcome compared to knee arthrodesis in severe periprosthetic joint infection.

Aims: In cases of severe periprosthetic joint infection (PJI) of the knee, salvage procedures such as knee arthrodesis (KA) or above-knee amputation (AKA) must be considered. As both treatments result in limitations in quality of life (QoL), we aimed to compare outcomes and factors influencing complication rates, mortality, and mobility. Methods: Patients with PJI of the knee and subsequent KA or AKA between June 2011 and May 2021 were included. Demographic data, comorbidities, and patient history were analyzed. Functional outcomes and QoL were prospectively assessed in both groups with additional treatment-specific scores after AKA. Outcomes, complications, and mortality were evaluated. Results: A total of 98 patients were included, 52 treated with arthrodesis and 47 with AKA. The mean number of revision surgeries between primary arthroplasty and arthrodesis or AKA was 7.85 (SD 5.39). Mean follow-up was 77.7 months (SD 30.9), with a minimum follow-up of two years. Complications requiring further revision surgery occurred in 11.5% of patients after arthrodesis and in 37.0% of AKA patients. Positive intraoperative tissue cultures obtained during AKA was significantly associated with the risk of further surgical revision. Two-year mortality rate of arthrodesis was significantly lower compared to AKA (3.8% vs 28.3%), with age as an independent risk factor in the AKA group. Functional outcomes and QoL were better after arthrodesis compared to AKA. Neuropathic pain was reported by 19 patients after AKA, and only 45.7% of patients were fitted or were intended to be fitted with a prosthesis. One-year infection-free survival after arthrodesis was 88.5%, compared to 78.5% after AKA. Conclusion: Above-knee amputation in PJI results in high complication and mortality rates and poorer functional outcome compared to arthrodesis. Mortality rates after AKA depend on patient age and mobility, with most patients not able to be fitted with a prosthesis. Therefore, arthrodesis should be preferred whenever possible if salvage procedures are indicated.

The Future of Total Elbow Arthroplasty: A Statistical Forecast Model for Germany.

This study provides a statistical forecast for the development of total elbow arthroplasties (TEAs) in Germany until 2045. The authors used an autoregressive integrated moving average (ARIMA), Error-Trend-Seasonality (ETS), and Poisson model to forecast trends in total elbow arthroplasty based on demographic information and official procedure statistics. They predict a significant increase in total elbow joint replacements, with a higher prevalence among women than men. Comprehensive national data provided by the Federal Statistical Office of Germany (Statistisches Bundesamt) were used to quantify TEA's total number and incidence rates. Poisson regression, exponential smoothing with Error-Trend-Seasonality, and autoregressive integrated moving average models (ARIMA) were used to predict developments in the total number of surgeries until 2045. Overall, the number of TEAs is projected to increase continuously from 2021 to 2045. This will result in a total number of 982 (TEAs) in 2045 of mostly elderly patients above 80 years. Notably, female patients will receive TEAs 7.5 times more often than men. This is likely influenced by demographic and societal factors such as an ageing population, changes in healthcare access and utilization, and advancements in medical technology. Our projection emphasises the necessity for continuous improvements in surgical training, implant development, and rehabilitation protocols.

Phosphorus Knowledge and Dietary Intake of Phosphorus of US Adults Undergoing Dialysis.

Abnormal serum phosphorus is a concern for adults undergoing dialysis due to the risk for mortality and morbidity. General recommendations for maintaining serum phosphorus within normal limits is monitoring dietary intake of phosphorus and taking phosphate binders, as prescribed. However, limited research is available about adults' phosphorus knowledge and dietary intake of phosphorus. The purpose of this cross-sectional study was to determine the association between phosphorus knowledge and dietary intake of phosphorus of adults on dialysis. An online Qualtrics survey was conducted during February-September 2023. Participants (n = 107) responded to the 74-item questionnaire (30-day food frequency questionnaire, phosphorus knowledge questionnaire, and demographic questions). Analysis included frequencies, descriptive statistics, t-tests, and Spearman correlations. JMP SAS v16 was used with a statistical significance of p < 0.05. Of the participants, 57.0% (n = 61) were on peritoneal dialysis and 43.0% (n = 46) were on hemodialysis. Average phosphorus knowledge score was 10.6 ± 3.0 out of 19 or 55.8%, with those on peritoneal dialysis having lower scores (54.7%) compared to participants on hemodialysis (58.1%) (p < 0.05). The daily average dietary phosphorus intake was 605 ± 297 mg. Participants on peritoneal dialysis consumed more phosphorus (625 mg) compared to participants on hemodialysis (576 mg) (p < 0.05). There was no association with phosphorus knowledge scores and dietary intake of phosphorus. There were positive correlations between discussing about phosphorus, knowing serum phosphorus concentration, and phosphorus knowledge scores. These results can aid practitioners in providing tailored nutrition education among adults on dialysis.

Indole-3-pyruvate: Analysis and Control of Tautomerism and Reactivity.

It is well-known in biochemistry that structure confers function, meaning that chemical structural elucidation is critical to truly understanding the function of a given metabolite. Indole-3-pyruvate (IPyA) exists in an equilibrium between the keto and enol tautomeric forms. IPyA is suggested to play a role in immune function; however, determining whether the tautomeric forms function differently can only be studied if an analytical method is capable of distinguishing between the two forms. Herein, we describe the use of UHPLC-HRMS to gain insight into the physical variables that govern IPyA tautomer equilibrium, reactivity, and detection limit. We use hydrogen-deuterium exchange (HDX) to identify enol and keto peaks, and we show that tautomers exhibit a valley of fronting followed by a tailing peak shape (though separation is still attainable) and identical MS/MS spectra. We observed drastically different ratios of keto and enol forms in different solvents, which is an important consideration for in vitro studies. IPyA was found to be highly unstable with accelerated reactivity in peroxides. Through in vitro reactivity studies, IPyA produced a myriad of known and unknown metabolites via nonenzymatic processes, many of which were mapped in vivo via the analysis of human plasma. Finally, we show that vitamin C (ascorbic acid) can slow this reactivity and enable sensitive detection in whole blood.

The projected increase of vertebral osteomyelitis in Germany implies a demanding challenge for future healthcare management of aging populations.

PURPOSE: Since an increase in the occurrence of native vertebral osteomyelitis (VO) is expected and reliable projections are missing, it is urgent to provide a reliable forecast model and make it a part of future health care considerations. METHODS: Comprehensive nationwide data provided by the Federal Statistical Office of Germany were used to forecast total numbers and incidence rates (IR) of VO as a function of age and gender until 2040. Projections were done using autoregressive integrated moving average model on historical data from 2005 to 2019 in relation to official population projections from 2020 to 2040. RESULTS: The IR of VO is expected to increase from 12.4 in 2019 to 21.5 per 100,000 inhabitants [95% CI 20.9-22.1] in 2040. The highest increase is predicted in patients over 75 years of age for both men and women leading to a steep increase in absolute numbers, which is fourfold higher compared to patients younger than 75 years. While the IR per age group will not increase any further after 2035, the subsequent increase is due to a higher number of individuals aged 75 years or older. CONCLUSIONS: Our data suggest that increasing IR of VO will seriously challenge healthcare systems, particularly due to demographic change and increasing proportions of populations turning 75 years and older. With respect to globally fast aging populations, future health care policies need to address this burden by anticipating limitations in financial and human resources and developing high-level evidence-based guidelines for prevention and interdisciplinary treatment.

Complex elbow fracture-dislocations- what factors are associated with a poor post-operative outcome?

PURPOSE: Despite standardized treatment algorithms, patients with complex elbow fracture-dislocation frequently suffer from poor post-operative elbow function leading to reduced quality of life. Up to now, there is no valuable data regarding risk factors that lead to poor post-operative outcome after surgical reconstruction of complex elbow fracture-dislocations. METHODS: From 06/2010 to 12/2020 134 patients (51.3 ± 15.1 years, 44% women) undergoing surgical treatment of complex elbow fracture-dislocations could be included in this study. Follow-up period was 4.4 years (SD 2.5). All patients were clinically evaluated for elbow movement, elbow stability and common elbow scores (MEPS, OES, DASH-Score). Potential risk factors for poor post-operative outcome were identified using bi- and multivariate analyses. RESULTS: Overall good post-operative outcome has been achieved, mean MEPS was 88.8 ± 17.6. Post-operative complications occurred in 31.3% of the cases, while 25.4% required surgical revision. Patients with transolecranon dislocation fractures showed the significantly worst functional outcomes (p = 0.01). In addition, it has been shown that a patient's age of more than 70 years (OR = 10, p = 0.003) and a BMI of more than 35 kg/m2 (OR = 7.6, p = 0.004) are independent risk factors for a poor post-operative outcome. In contrast, gender and time to surgery showed no significant influence on post-operative outcome. CONCLUSION: In most cases, good post-operative functional results can be achieved using standardized treatment protocols. However, complication and revision rates remain high. Patients older than 70 years of age or with a BMI over 35 kg/m2 are at risk for an inferior outcome and require close follow-up monitoring.

Radiographic Evidence of Sufficient Transverse Plane Alignment after Weil Osteotomy without Screw Fixation.

Weil osteotomy is a proven procedure to restore the harmonic distal parabola of the forefoot. In addition to the proximal displacement of the head in the sagittal plane, a displacement in the transverse plane may be necessary, with the refixation of the displaced metatarsal head historically performed by screw fixation. We aimed to determine the radiological differences among 136 feet of 127 patients with 256 Weil osteotomies retrospectively enrolled and divided into groups with (n = 182) and without (n = 74) screw fixation. Demographic data, radiographic union, pre- and postoperative metatarsal angles, and differences in the dorsoplantar view were evaluated. The mean follow-up period was 3.6 months. The mean preoperative metatarsophalangeal angle was 9.24°, and the mean postoperative angle was 12.99°. The restoration of the transversal alignment plane was equally successful in both groups, with a mean extent of angle correction of 10.58°. No nonunions of the osteotomized metatarsals were observed. The radiographic comparisons revealed no significant difference between the groups (p > 0.05). However, visibility of the joint space of the metatarsophalangeal joint was achieved significantly more often in the group without screw fixation (p < 0.05). In the absence of bony malunion and the satisfactory restoration of a harmonious parabola of the forefoot, apparently there does not appear to be a necessity for regular screw fixation after Weil osteotomy based on the available data from the present study.

Mid-term outcome following radial head arthroplasty in acute trauma: risk factors for poor outcome.

BACKGROUND: The aims of this study were to evaluate the outcomes of a single type of radial head implant in a large cohort of patients at mid-term follow-up and to determine the associated risk factors for inferior functional outcomes. METHODS: We performed a retrospective follow-up assessment of 65 patients (33 women and 32 men; mean age, 53.3 years [range, 22-81 years]) who underwent radial head arthroplasty (RHA) for acute trauma between 2012 and 2018, after a minimum follow-up period of 3 years. The Mayo Elbow Performance Score, Oxford Elbow Score, Disabilities of the Arm, Shoulder and Hand score, and Mayo Modified Wrist Score were evaluated, and all available radiographs were analyzed. All complications and revision procedures were assessed. Bivariate and multivariate regression analyses were performed to identify potential risk factors for a poor outcome following RHA. RESULTS: After an average follow-up period of 4.1 years (range, 3-9.4 years), the mean Mayo Elbow Performance Score was 77.2 (standard deviation [SD], 18.9); mean Oxford Elbow Score, 32.0 (SD, 10.6); mean Mayo Modified Wrist Score, 74.6 (SD, 13.7); and mean Disabilities of the Arm, Shoulder and Hand score, 29.0 (SD, 21.2). Average range of motion measured 10° (SD, 15°) in extension, 125° (SD, 14°) in flexion, 81° (SD, 14°) in pronation, and 63° (SD, 24°) in supination. The overall complication and reoperation rates were 38.5% and 30.8%, respectively, with severe elbow stiffness being the most common reason for revision. Patient age >50 years, the use of an external fixator, the presence of accompanying medial collateral ligament injuries, and the development of higher-grade osteoarthritis were associated with a poor outcome. CONCLUSION: Satisfactory medium-term outcomes can be achieved using a monopolar, long-stemmed RHA in patients with acute trauma. However, complication and revision rates are high, frequently leading to inferior outcome scores. Additionally, a higher patient age, the use of an external fixator, the presence of accompanying medial collateral ligament injuries, and the occurrence of higher-grade osteoarthritis were associated with a poor outcome; these factors should raise awareness by the treating trauma surgeon.

Preservation of the Subtalar Joint Determines Outcomes in a 10-Year Evaluation of Ankle Arthrodesis.

Posttraumatic osteoarthritis may lead to surgical fusion of the ankle joint if non-surgical therapy fails. The indication for a fusion of the joint is based on the pain and disability of the patient, radiographic imaging, and surgeon experience, with no strict guidelines. We aimed to compare outcomes after tibiotalocalcaneal arthrodesis (TTCA) and tibiotalar arthrodesis (TTA) to highlight the functional importance of the subtalar joint. In total, 432 patients with ankle arthrodesis were retrospectively enrolled. Group A (n = 216) underwent TTCA; group B (n = 216) underwent TTA. Demographics, Olerud & Molander Ankle Score (OMAS), Foot Function Index (FFI-D), and Short Form-12 Questionnaire (SF-12) were recorded at a mean follow-up of 6.2 years. The mean OMAS was 50.7; the mean FFI-D was 68.9; the mean SF-12 physical component summary was 39.1. These scores differed significantly between the groups (p < 0.001). The overall revision rate was 18%, primarily for revision of non-union and infection (p < 0.001). Approximately 16% of group A and 26% of group B were able to return to previous work (p < 0.001). Based on significantly worse clinical scores of TTCA compared to TTA and the prolonged downtime and permanent incapacity, the indication for a generous subtalar joint arthrodesis with planned ankle arthrodesis should always be critically examined.

Survival of Patient-Specific Unicondylar Knee Replacement.

Unicompartmental knee arthroplasty (UKA) in isolated medial or lateral osteoarthritis leads to good clinical results. However, revision rates are higher in comparison to total knee arthroplasty (TKA). One reason is suboptimal fitting of conventional off-the-shelf prostheses, and major overhang of the tibial component over the bone has been reported in up to 20% of cases. In this retrospective study, a total of 537 patient-specific UKAs (507 medial prostheses and 30 lateral prostheses) that had been implanted in 3 centers over a period of 10 years were analyzed for survival, with a minimal follow-up of 1 year (range 12 to 129 months). Furthermore, fitting of the UKAs was analyzed on postoperative X-rays, and tibial overhang was quantified. A total of 512 prostheses were available for follow-up (95.3%). Overall survival rate (medial and lateral) of the prostheses after 5 years was 96%. The 30 lateral UKAs showed a survival rate of 100% at 5 years. The tibial overhang of the prosthesis was smaller than 1 mm in 99% of cases. In comparison to the reported results in the literature, our data suggest that the patient-specific implant design used in this study is associated with an excellent midterm survival rate, particularly in the lateral knee compartment, and confirms excellent fitting.

Coronoid tip fractures in terrible triad injuries can be safely treated without fixation.

INTRODUCTION: The optimal treatment of terrible triad injuries of the elbow (TTI) remains topic of ongoing discussion. The aim of this study was to determine whether different treatment strategies for coronoid tip fractures in terrible triad injuries influences the clinical and radiological results in a mid-term follow-up. METHODS: A total of 62 patients with surgical treatment of a TTI including a coronoid tip fracture (37 women, 25 men; mean age, 51 years) were available for follow-up assessment after an average of 4.2 years (range 24-110 months). Thirteen patients had O'Driscoll 1.1 and 49 O'Driscoll 1.2 coronoid fractures, of which 26 were treated with and 36 without fixation. Range of motion, the Mayo Elbow Performance Score (MEPS), Oxford Elbow Score (OES), and Disabilities of the Arm, Shoulder and Hand (DASH) score as well as grip strength were evaluated. Radiographs were analyzed for all participants. RESULTS: No significant benefit in outcome variables could be detected between patients, whose coronoid had been fixed, compared to patients without fixation of the coronoid. In the coronoid fixation group, patients had mean outcome scores of 81.5 ± SD 19.1 (range 35-100) for MEPS, 31.0 ± SD 12.5 (range 11-48) for OES and 27.7 ± SD 23 (range 0-61) for DASH score, while in the no-fixation group, mean MEPS was 90.8 ± SD 16.5 (range 40-100), mean OES was 39.0 ± SD 10.4 (range 16-48) and mean DASH score was 14.5 ± SD 19.9 (range 0-48). Mean range of motion was 116° ± SD 21° (range 85-140°) versus 124° ± SD 24° (range 80-150°) in extension-flexion and 158° ± SD 23° (range 70-180°) versus 165° ± SD 12° (range 85-180°) in pronation-supination. Overall complication rate was 43.5% and revision rate was 24.2%, with no significant differences between both groups. Suboptimal results were more frequently seen in patients who had degenerative or heterotopic changes on their latest radiograph. CONCLUSIONS: Sufficient elbow stability and good outcomes can be achieved in most patients with TTI and coronoid tip fractures. Although some bias in treatment allocation and group heterogeneity cannot be completely omitted, our analysis detected no significant benefit in outcome when the coronoid tip fracture has been fixed compared to patients with non-fixed coronoid tip. Therefore, we would suggest a no-fixation approach for coronoid tip fractures as primary treatment in TTI of the elbow. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

[Terrible triad injuries]. / Terrible-Triad-Verletzungen.

The complex injury pattern of a posterior elbow dislocation with concomitant radial head and coronoid fractures is usually referred to as a terrible triad injury. Due to the concomitant compromise of several osteoligamentous structures of the elbow joint relevant for stability, these injuries pose a particularly major challenge to the treating trauma surgeons. For this reason, a careful preoperative analysis of all relevant injury components is mandatory in order to make an adequate treatment decision. In most cases, surgical treatment addressing all elements relevant for stability is necessary to achieve a stable and congruent elbow joint. Only this enables early functional follow-up treatment and minimizes the complication rate. Delayed or even insufficient treatment with persistent (sub)dislocation must be avoided at all costs, otherwise there is a high risk of serious posttraumatic functional disorders of the elbow with rapid progression of osteoarthritis.

Arthroscopic Bankart repair: how many knotless anchors do we need for anatomic reconstruction of the shoulder?-a prospective randomized controlled study.

PURPOSE: The optimal strategy for surgical repair of traumatic anterior shoulder instability remains controversial. While several study groups have reported that the clinical and radiological outcomes of arthroscopic procedures performed with two anchors are not fully adequate, these conclusions are not supported by the findings published in other studies. A prospective randomized study was conducted to compare the structural and clinical outcomes of surgical procedures involving two vs. three anchors. METHODS: Patients who underwent arthroscopic Bankart repair were randomly assigned to either Group I, which underwent procedures involving two double-loaded 3.5-mm knotless anchors, or Group II, which underwent procedures involving three single-loaded 2.9-mm knotless anchors. All patients underwent bilateral MRI assessments at a minimum of 12 months and clinical assessment at a minimum of 24 months postoperatively. To evaluate the reconstruction of the labral capsular ligamentous complex (LCLC), the labrum-glenoid height index (LGHI), restored labral height (LH), and labral slope (LS) were measured for both shoulders. For clinical assessment, the redislocation rate and functional outcome scores (Constant score (CS), American Shoulder and Elbow Surgeon score (ASES), Walch Duplay score (WDS), and Rowe score (RS)) were evaluated at follow-up visits. RESULTS: Bankart repair with two knotless anchors showed lower values for anterior reconstruction of the LCLC compared to the uninjured contralateral shoulder. Likewise, significant differences were noted when comparing these measurements to those from patients who underwent reconstruction with three anchors. No differences were demonstrated with regard to the reconstruction of the inferior LCLC. Clinical assessment showed good to excellent results in both groups. In total, three patients experienced redislocation of the shoulder: two in group I and one in group II. No significant differences were found with respect to clinical outcomes and redislocation rates. CONCLUSION: Bankart repair with both two and three knotless anchors results in effective anatomical reconstruction of the labral capsular ligamentous complex. Although the two-anchor technique yields significantly lower values for the anterior portion compared with the contralateral side, none of these differences reach clinical relevance as per our original definition.

Projections From Surgical Use Models in Germany Suggest a Rising Number of Spinal Fusions in Patients 75 Years and Older Will Challenge Healthcare Systems Worldwide.

BACKGROUND: Spinal fusion is a well-established procedure in the treatment of degenerative spinal diseases. Previous research shows that the use of this operative treatment has been growing in recent decades in industrialized countries and has become one of the most cost-intensive surgical procedures. It seems that in some countries such as Germany-with its large, industrialized, European population-this increase is mainly driven by demographic changes with low fertility rates, increasing life expectancy, and an aging population. Based on current projections, however, Germany faces a population trend that many other countries are likely to follow within a few decades. An increasingly shrinking and aging working population may eventually put the healthcare system under enormous pressure, with greater demands for spinal fusions and associated higher costs. Thus, we aimed to provide reliable projections regarding the future demand for posterior spinal fusion procedures including age- and gender-related trends up to 2060, which will be necessary for future resource planning and possible improvements in actual treatment strategies. QUESTIONS/PURPOSES: (1) How is the use of posterior spinal fusions in Germany expected to change from 2019 through 2060, if currents trends continue? (2) How is the use of posterior spinal fusions in Germany expected to change depending on patients' age and gender during this time period? METHODS: Comprehensive nationwide data provided by the Federal Statistical Office, the official institution for documenting all data on operations and procedures performed in Germany, were used to quantify posterior spinal fusion rates as a function of calendar year, age, and gender. Because there is a lack of evidence regarding future trends in the use of posterior spinal fusions, an autoregressive integrated moving average model on historical procedure rates from 2005 to 2019 in relation to official population projections from 2020 to 2060 was chosen to forecast future absolute numbers and incidence rates of this procedure in Germany. Long-term forecasting is more prone to unexpected disruptions than forecasting over short-term periods; however, longer spans facilitate estimates of how trends may challenge future healthcare systems if those trends continue, and thus are useful for research and planning. RESULTS: The incidence rate of posterior spinal fusion was projected to increase by approximately 83% (95% CI 28% to 139%) to 102% per 100,000 inhabitants (95% CI 71% to 133%) in 2060, with a 1.3-fold higher rate of women undergoing surgery in terms of absolute numbers. The highest increase identified by the model occurred in patients 75 years and older with 38,974 (95% CI 27,294 to 50,653) posterior spinal fusions in 2060, compared with 14,657 in 2019. This trend applied for both women and men, with a 246% (95% CI 138% to 355%) increase in the total number of posterior spinal fusions for women 75 years and older and a 296% (95% CI 222% to 370%) increase for men 75 years and older. At the same time, posterior spinal fusions in all age groups younger than 55 years were projected to follow a constant or even negative trend up to 2060. CONCLUSION: Our findings suggest that increasing use of posterior spinal fusion, particularly in patients 75 years and older, will challenge healthcare systems worldwide if current trends persist. This study may serve as a model for many other industrialized countries facing similar demographic and procedure-specific developments in the future. This emphasizes the need to focus on frailty research as well as appropriate financial and human resource management. Effective perioperative medical management, multidisciplinary treatment, and interinstitutional protocols are warranted, especially in older patients as we attempt to manage these trends in the future. LEVEL OF EVIDENCE: Level III, economic and decision analysis.

The Conventional Weil Osteotomy Does Not Require Screw Fixation.

The Weil osteotomy is an established procedure to reduce plantar pressure in chronic metatarsalgia. Historically, the refixation of the displaced metatarsal head is performed by screw fixation. We aimed to demonstrate that screw fixation is not always necessary. Between 2016 and 2021, 155 patients with 278 Weil osteotomies (20 males and 135 females, mean age: 63 years) were retrospectively enrolled. Group A (n = 96) underwent 195 Weil osteotomies with screw fixation; group B (n = 59), 83 without screw fixation. Demographic, Visual Analog Scale Foot and Ankle (VAS-FA), SF-12 questionnaire, and toe mobility data were recorded. The mean follow-up period was 4.5 years. The mean VAS-FA was 75.5; mean SF-12 physical component summary, 42.0; and mean SF-12 mental component summary, 51.0. The overall revision rate was 20% (group A: 25%, group B: 10.2%), primarily for arthrolysis of the metatarsophalangeal joint in group A. Clinical comparisons showed no significant difference between the groups (p > 0.05). The revision rate was significantly higher in group A (p < 0.05), with equal satisfaction in clinical outcomes. Based on the available data, the need for regular screw fixation after a Weil osteotomy cannot be justified.

Value of closed suction drainage in arthroscopic and minimally invasive surgery of the ankle joint: a prospective randomised study.

INTRODUCTION: Closed suction drainage is an established procedure in arthroscopic surgery. It is intended to reduce the retention of wound and irrigation fluids, which form the basis for postoperative swelling, pain, and infection. However, currently, there is no scientific review of the actual benefit of this procedure. METHODS: Between 2020 and 2021, 84 patients (53 males, 31 females; mean age: 42 years) were prospectively randomised into this study. The patients underwent arthroscopic surgery of the ankle joint with (group A) or without (group B) insertion of a closed suction drain (42 patients per group). Assessments included upper ankle swelling using the figure-of-eight-20 method, pain preoperatively and 48 h postoperatively, and unexpected events within 6 weeks postoperatively. RESULTS: The measurements performed 48 h postoperatively showed a mean circumferential increase of 1.38 cm (1.48 and 1.28 cm in groups A and B, respectively; p > 0.05) in all patients. The mean pain at rest, assessed using the visual analogue scale (maximum 10 points), was 2.7 and 2.4 in groups A and B, respectively (p > 0.05). Overall, two minor complications occurred: residual swelling in group A and persistent limitation of movement in group B. The average length of hospital stay was 2.4 days (p > 0.05). CONCLUSIONS: Based on the available data, the routine insertion of a closed suction drainage at the upper ankle does not offer any objective benefit and must be considered obsolete. From both a medical and an economic point of view, the decision to conduct this procedure should be justified on an individual basis. LEVEL OF EVIDENCE: Level I, prospective randomised trial.

Tissue sampling is non-inferior in comparison to sonication in orthopedic revision surgery.

BACKGROUND: The aim of this study was to assess the role of sonication fluid cultures in detecting musculoskeletal infections in orthopedic revision surgery in patients suspected of having peri-prosthetic joint infection (PJI), fracture-related infections (FRI), or postoperative spinal implant infections (PSII). METHODS: Between 2016 and 2019, 149 cases with a data set including sonication fluid cultures and tissue specimen and histological analysis were included. Accuracy of each diagnostic tool as well as the influence of antibiotic therapy was analyzed. Pathogens identified in the sonication cultures and in the associated tissue samples were compared based on the matching of the antibiograms. Therapeutic benefits were then assessed. RESULTS: Of 149 cases, 43.6% (n = 65) were identified as PJI, 2.7% (n = 4) as FRI, 12.8% (n = 19) as PSII, 6.7% (n = 10) as aseptic non-union, and 34.2% (n = 51) as aseptic implant loosening. The sensitivity and specificity of tissue and synovial specimens showed no significant difference with respect to sonication fluid cultures (sensitivity/specificity: tissue: 68.2%/96.7%; sonication fluid cultures: 60.2%/98.4%). The administration of antibiotics over 14 days prior to microbiological sampling (n = 40) resulted in a lower sensitivity of 42.9% each. Histological analysis showed a sensitivity 86.3% and specificity of 97.4%. In 83.9% (n = 125) of the cases, the results of sonication fluid cultures and tissue specimens were identical. Different microorganisms were found in only four cases. In 17 cases, tissue samples (n = 5) or sonication (n = 12) were false-negatives. CONCLUSION: Sonication fluid culture showed no additional benefit compared to conventional microbiological diagnostics of tissue and synovial fluid cultures. Preoperative administration of antibiotics had a clearly negative effect on microbiologic test accuracy. In over 83.9% of the cases, sonication fluid and tissue cultures showed identical results. In the other cases, sonication fluid culture did not further contribute to the therapy decision, whereas other factors, such as fistulas, cell counts, or histological analysis, were decisive in determining therapy.

Conflicting effects of recombination on the evolvability and robustness in neutrally evolving populations.

Understanding the benefits and costs of recombination under different scenarios of evolutionary adaptation remains an open problem for theoretical and experimental research. In this study, we focus on finite populations evolving on neutral networks comprising viable and unfit genotypes. We provide a comprehensive overview of the effects of recombination by jointly considering different measures of evolvability and mutational robustness over a broad parameter range, such that many evolutionary regimes are covered. We find that several of these measures vary non-monotonically with the rates of mutation and recombination. Moreover, the presence of unfit genotypes that introduce inhomogeneities in the network of viable states qualitatively alters the effects of recombination. We conclude that conflicting trends induced by recombination can be explained by an emerging trade-off between evolvability on the one hand, and mutational robustness on the other. Finally, we discuss how different implementations of the recombination scheme in theoretical models can affect the observed dependence on recombination rate through a coupling between recombination and genetic drift.

Proximal ulna non-union: treatment concept and postoperative outcome.

PURPOSE: Non-union of the proximal ulna is a serious complication after surgical treatment of olecranon and complex elbow fractures, frequently leading to poor functional outcome. To date, there is a lack of data regarding optimal treatment strategies and functional outcome parameters after surgical revision. METHODS: From 02/2010 to 12/2018, 31 patients undergoing surgical treatment of proximal ulna non-union could be included. Follow-up period was seven years (SD 2.5 years). All patients were clinically assessed using a clinical assessment tool set and standard elbow scores (MEPS, OES, DASH score). All complications and unplanned revision surgeries were recorded and all radiographic material was analyzed. RESULTS: Initial non-union procedures were performed at an average of 6.6 months (SD 3 months) after the index procedures. Those included the use of autologous spongiosa graft in all patients and concomitant compression re-osteosynthesis in 28 patients. Radiological consolidation was achieved in all patients. Overall, patients achieved a good to fair functional outcome with Mayo elbow performance score measuring 78.5 (SD 9.1), DASH score 34.7 (SD 14.4), and Oxford elbow score 31.2 (SD 6.6) points. Initial malreduction/implant-malposition could be identified as a main reason for the occurrence of the non-union. Furthermore, inferior postoperative outcome was detected in patients > 60 years and BMI > 30 kg/m2. CONCLUSION: Using a standardized protocol, bony union and acceptable functional outcomes can be achieved in proximal ulna non-unions. However, surgeons should be aware of potential risk factors and proper initial fracture reduction as key to achieve sufficient bone healing.

A 10-Year Follow-Up of Ankle Syndesmotic Injuries: Prospective Comparison of Knotless Suture-Button Fixation and Syndesmotic Screw Fixation.

Background: Acute syndesmosis injury (ASI) is an indication for surgical stabilization if instability is confirmed. In recent years, fixation using the knotless suture-button (SB) device has become increasingly established as an alternative to set screw fixation (SF). This study directly compared the clinical long-term results after prospective randomized inclusion. Materials and Methods: Between 2011 and 2012, 62 patients with ASI were enrolled in a prospective, randomized, and monocentric study. Forty-one patients were available for a 10-year follow-up ((31 males and 10 females), including 21 treated with SB (mean age 44.4 years), and 20 with SF (mean age 47.2 years)). In addition to comparing the demographic data and syndesmosis injury etiology, follow-up assessed the Olerud−Molander Ankle Score (OMAS) and FADI-Score (Foot and Ankle Disability Index Score) with subscales for activities of daily living (ADL) and sports activity. Results: The mean OMAS was 95.98 points (SB: 98.81, SF: 93.00), the mean FADI ADL was 97.58 points (SB: 99.22, SF: 95.86), and the mean FADI Sport was 94.14 points (SB: 97.03, SF: 91.10). None of the measurements differed significantly between the groups (p > 0.05). No clinical suspicion of chronic instability remained in any of the patients, regardless of treatment. Conclusions: The short-term results showed that athletes in particular benefit from SB fixation due to their significantly faster return to sports activities. However, the available long-term results confirm a very good outcome in the clinical scores for both approaches. Chronic syndesmotic insufficiency was not suspected in any of the patients. Level of evidence: I, randomized controlled trial.