Prediction of individual graft for anterior cruciate ligament reconstruction using anthropometric data.

INTRODUCTION: Multiple options for individual anterior cruciate ligament (ACL) reconstruction exist; still, there are no guidelines for the preoperative preparation. The aim of this study was to assess the correlation between patients' anthropometric data (height, weight, and age) and measurements of potential tendons (quadriceps-, patella, hamstrings tendon) for an anterior cruciate ligament reconstruction. MATERIAL AND METHODS: MR images of 102 patients have been analyzed. Measurements of the ACL were performed with respect to its length and angle. The diameter and length as well as width of the quadriceps and patella tendon, the cross-sectional area (CSA) and diameter of the hamstring tendons have been assessed. Patients' height, weight, BMI, sex and age have been recorded. The correlations of these measurements with the patients' anthropometric data have been calculated. Inter-rater and intra-rater reliability based on intra-class correlation (ICC) was evaluated. RESULTS: The mean lengths of the ACL were 29.8 ± 3.5 mm, tibial insertion sites 15.8 ± 2.5 mm and femoral insertion sites 15.2 ± 3.0 mm. Thickness of the quadriceps tendons was 4.7 ± 1.1 mm and patella tendon 3.2 ± 0.7 mm. The patients' height showed significant positive correlations with the CSA of the hamstring tendon measurements, the length of the ACL, and the insertion sites of the ACL. Patients' weight showed significant positive correlations with patella tendon thickness, the CSA of the hamstring tendons, the length of the ACL, and the tibial and femoral insertion sites. Patients' age showed a significant positive correlation with patella tendon thickness. The ICCs for intra- and inter-rater reliability were 0.98 (95% CI 0.95-0.99, p < 0.001) and 0.94 (95% CI 0.88-0.99, p < 0.001). CONCLUSION: Anthropometric data with respect to height, weight, and sex can help to predict the dimension of tendons for ACL reconstruction and do correlate with ACL tendon. Patients at risk for small graft dimensions and failure are younger than 20 years and physically active. MRIs of patients at risk for small graft dimensions should be analyzed on tendon length and cross section areas preoperatively to determine the appropriate tendon harvest and fixation technique.

On Measuring Implant Fixation Stability in ACL Reconstruction.

Numerous methods and devices are available for implant fixation in anterior cruciate ligament (ACL) reconstruction. Biomechanical data indicate high variability in fixation stability across different devices. This study aims to provide a better insight into measuring the structural characteristics and mechanical behavior of ACL implant fixations. Fourteen human tibial specimens with reconstructed ACLs were subjected to progressively increasing dynamic loading until failure. The motions of the tibia, the proximal and distal graft ends, as well as the testing frame and actuator, were continuously recorded via a motion tracking system. Significantly higher displacements of the machine actuator (1.0 mm at graft slippage onset, and 12.2 mm at ultimate load) were measured compared to the displacements of the proximal (0.8 and 4.3 mm, respectively) and distal graft (0.1 and 3.4 mm, respectively) ends. The displacements measured at different sites showed significant correlations. The provided data suggest significant and systematic inaccuracies in the stiffness and slippage of the fixation when using machine displacement, as commonly reported in the literature. The assessment of the distal graft displacement excludes the artifactual graft elongation, and most accurately reflects the graft slippage onset indicating clinical failure. Considering the high displacement at the ultimate load, the ultimate load could be used as a standardized variable to compare different fixation methods. However, the ultimate load alone is not sufficient to qualitatively describe fixation stability.

The impact of implant material and patient age on the long-term outcome of secondary cranioplasty following decompressive craniectomy for severe traumatic brain injury.

BACKGROUND: Secondary cranioplasty (CP) is considered to support the neurological recovery of patients after decompressive craniectomy (DC), but the treatment success might be limited by complications associated to confounders, which are not yet fully characterized. The aim of this study was to identify the most relevant factors based on the necessity to perform revision surgeries. METHODS: Data from 156 patients who received secondary CP following DC for severe traumatic brain injury (TBI) between 1984 and 2015 have been retrospectively analyzed and arranged into cohorts according to the occurrence of complications requiring surgical intervention. RESULTS: Cox regression analysis revealed a lower revision rate in patients with polymethylmethacrylate (PMMA) implants than in patients with autologous calvarial bone (ACB) implants (HR 0.2, 95% CI 0.1 to 1.0, p = 0.04). A similar effect could be observed in the population of patients aged between 18 and 65 years, who had a lower risk to suffer complications requiring surgical treatment than individuals aged under 18 or over 65 years (HR 0.4, 95% CI 0.2 to 0.9, p = 0.02). Revision rates were not influenced by the gender (p = 0.88), timing of the CP (p = 0.53), the severity of the TBI (p = 0.86), or the size of the cranial defect (p = 0.16). CONCLUSIONS: In this study, the implant material and patient age were identified as the most relevant parameters independently predicting the long-term outcome of secondary CP. The use of PMMA was associated with lower revision rates than ACB and might provide a therapeutic benefit for selected patients with traumatic cranial defects.

Tibial ACL insertion site length: correlation between preoperative MRI and intra-operative measurements.

PURPOSE: This study was undertaken primarily to identify the tibial insertion site length of ruptured ACL fibres in patients undergoing primary ACL reconstruction. A secondary aim was to evaluate the correlation of pre- and intra-operative measurements. METHODS: In 146 patients undergoing primary ACL reconstruction, a preoperative measurement on MRI of the tibial ACL insertion site length was taken by two raters and then compared with single surgeon's intra-operative measurements using a specialized ruler. Inclusion criteria were primary ACL reconstruction and MRI performed within 3 months prior to surgery on one specific MRI machine at the study centre. Inter-rater and intra-rater reliability based on intra class correlation (ICC) was calculated. Additionally, correlation between preoperative and postoperative measurements and the anthropometric data was assessed using Pearson correlation. RESULTS: The tibial ACL insertion site had a mean length of 16.6 ± 1.6 mm (11.9-21.0) as measured by MRI, and 16.4 ± 1.6 mm (11.0-20.0) as measured intra-operatively. The ICCs for intra- and inter-rater reliability of the MRI measurements were 0.99 (95 % CI 0.97; 0.99; p < 0.001) and 0.81 (95 % CI 0.75; 0.86; p < 0.001), respectively. Regression analysis demonstrated, after controlling for subject height and weight, that the MRI measurements significantly predicted intra-operative measurement of tibial insertion site length (ß = 0.796; R (2)-change 0.77; p < 0.001). CONCLUSION: Preoperative measurement of the tibial ACL length is possible using MRI and can be a valuable aid in more efficient preoperative planning given the knowledge of expected dimensions of special knee structures. LEVEL OF EVIDENCE: III.

Optimized cartilage visualization using 7-T sodium ((23)Na) imaging after patella dislocation.

PURPOSE: Retropatellar cartilage lesions often occur in the course of recurrent patella dislocation. Aim of this study was to develop a more detailed method for examining cartilage tissue, in order to reduce patient discomfort and time of care. METHODS: For detailed diagnosing, a 7-T MRI of the knee joint and patella was performed in nine patients, with mean age of 26.4 years, after patella dislocation to measure the cartilage content in three different regions of interest of the patella. Axial sodium ((23)Na) images were derived from an optimized 3D GRE sequence on a 7-T MR scanner. Morphological cartilage grading was performed, and sodium signal-to-noise ratio (SNR) values were calculated. Mean global sodium values and SNR were compared between patients and volunteers. RESULTS: Two out of nine patients showed a maximum cartilage defect of International Cartilage Repair Society (ICRS) grade 3, three of grade 2, three of  grade 1, and one patient showed no cartilage defect. The mean SNR in sodium images for cartilage was 13.4 ± 2.5 in patients and 14.6 ± 3.7 in volunteers (n.s.). A significant negative correlation between age and global sodium SNR for cartilage was found in the medial facet (R = -0.512; R (2) = 0.26; p = 0.030). Mixed-model ANOVA yielded a marked decrease of the sodium SNR, with increasing grade of cartilage lesions (p < 0.001). CONCLUSIONS: Utilization of the (23)Na MR imaging will make earlier detection of alterations to the patella cartilage after dislocation possible and will help prevent subsequent disease due to start adequate therapy earlier in the rehabilitation process. LEVEL OF EVIDENCE: II.

Clinical outcome and osteoarthritic changes after surgical treatment of isolated capitulum humeri fractures with a minimum follow-up of five years.

PURPOSE: The aim of this study was to evaluate the functional outcome of patients treated for a fracture of the capitulum humeri and to analyze the grade of osteoarthritic changes. METHODS: Patients undergoing surgical reconstruction of isolated capitulum humeri fractures were included in a retrospective comparative analysis. Fractures were classified according to the Arbeitsgemeinschaft für Osteosynthesefragen (AO) and Dubberley and were functionally evaluated by the American Shoulder and Elbow Surgeons Score (ASES) and the Mayo Elbow Performance Index (MEPI). Levels of arthritic changes were measured with the Broberg and Morrey Score. Frequency of complications was evaluated whereby all results were compared to the ipsilateral, unaffected side. RESULTS: Thirteen patients, ten females (76.9 %) and three males (23.1 %), with a mean age of 48.7 ± 13.3 years were included in the study. Long-term follow-up range of motion (ROM) in the sagittal plane was significantly influenced by time of surgery (p < 0.001), and long-term follow-up with respect to pronation and supination by ROM of the healthy control (p < 0.05). The average ASES score was 37.8, and the Mayo Elbow Performance Index (MEPI) was 92.7. The mean level of degenerative arthritic changes was 1.9 ± 0.6 on the fractured side and significantly less (0.8 ± 0.8) on the healthy side (pF-test < 0.001). At a mean follow-up of 118.5 ± 52.4 months neither nonunion nor avascular necrosis were observed in any case. However, six cases of heterotopic ossification were identified. CONCLUSIONS: Satisfying functional outcomes and a low rate of osteoarthritic changes can be expected after the presented open reduction and internal fixation of capitulum humeri fractures. LEVEL OF EVIDENCE: Level IV - Case series; therapeutic study.

Transoral balloon kyphoplasty in a myeloma patient with painful osseous destruction of the corpus vertebrae axis.

Multiple myeloma is the most common primary malignant disease of the spine, which can lead to pathological fractures with consecutive instability and immobilizing pain, due to osseous destruction of individual vertebral bodies. The different surgical care is challenging, although good stabilization should be achieved if possible. The resulting blocking of micro-movements leads to pain minimization. However, this is a symptomatic therapy and does not address the primary disease. In the following, we report on successful transoral balloon kyphoplasty for the treatment of myeloma-related osteolysis with a pathological fracture of vertebral body C2, which led to a significant clinical improvement.

The optimal window for reconstruction of the anterior cruciate ligament (ACL) with respect to quadriceps atrophies lies within 21 to 100 days.

PURPOSE: The study's objective was to determine the optimal window for anterior cruciate ligament (ACL) reconstruction with respect to quadriceps atrophies and clinical outcome. METHODS: For this retrospective, comparative study, 115 patients aged under 35 were included, who received an ACL reconstruction between 2011 and 2016. They were divided into four groups, depending on the time to surgery, to determine the optimal window for reconstruction: (group 1: ≤21 d, group 2: <21d-56d≥, group 3: >56d-100d≥, group 4: >100d). Follow-up was performed one month postoperatively, after a mean of 4.9 (±5.3) months, and after a mean of 3.5 (±1.4) years. Primary endpoints included quadriceps muscle status, range of motion (ROM), pain, swelling, the International Knee Documentation Committee Subjective Knee Form (IKDC), the Lysholm-Score, the Knee Injury and Osteoarthritis Outcome Score (KOOS), and the Tegner-Activity-Scale (TAS). RESULTS: Significantly more quadriceps atrophies were observed in group 1 and group 4, representing reconstructions earlier than 21 and later than 100 days (29% and 41% vs. 9%; p = 0.032). The measurements of knee extension (p = 0.082) and ROM (p = 0.123) were comparable in all groups. Group 1 showed the least pain (0% vs. 15%; p = 0.285) and swelling (0% vs. 23%; p = 0.077) compared to all other groups one month postoperatively. A comparison of postoperative clinical scores revealed no significant differences, with group 1 exhibiting the lowest TAS levels. CONCLUSION: In patients who underwent ACL reconstruction within three weeks or after more than 100 days, a significantly higher incidence of quadriceps atrophy was observed, possibly attributable to the initial inflammatory phase or the delayed reconstruction affecting quadriceps function. However, this impairment may not be observable in elite athletes who undergo reconstruction within hours of the injury.

Delayed Meniscus Repair Lowers the Functional Outcome of Primary ACL Reconstruction.

BACKGROUND: Our purpose was to evaluate whether the time of intervention and the type of meniscus surgery (repair vs. partial meniscectomy) play a role in managing anterior cruciate ligament (ACL) reconstructions with concurrent meniscus pathologies. METHODS: We performed a prospective cohort study which differentiated between early and late ACL reconstructions with a cut-off at 3 months. Patients were re-evaluated after 2 years. RESULTS: Thirty-nine patients received an operation between 2-12 weeks after the injury, and thirty patients received the surgery between 13-28 weeks after trauma. The strongest negative predictive factor of the International Knee Documentation Committee subjective knee form in a hierarchical regression model was older age (ß = -0.49 per year; 95% CI [-0.91; -0.07]; p = 0.022; partial R2 = 0.08)). The strongest positive predictive factor was a higher preoperative Tegner score (ß = 3.6; 95% CI [0.13; 7.1]; p = 0.042; partial R2 = 0.07) and an interaction between meniscus repair surgery and the time of intervention (ß = 27; 95% CI [1.6; 52]; p = 0.037; partial R2 = 0.07), revealing a clinical meaningful difference as to whether meniscus repairs were performed within 12 weeks after trauma or were delayed. There was no difference whether partial meniscectomy was performed early or delayed. CONCLUSIONS: Surgical timing plays a crucial role when surgeons opt for a meniscus repair rather than for a meniscectomy.

Outcomes and potential for improvement in the prehospital treatment of penetrating chest injuries in a European metropolitan area: A retrospective analysis of 2009 - 2017.

BACKGROUND: Trauma is the leading cause of death in patients <45 years living in high-resource settings. However, penetrating chest injuries are still relatively rare in Europe - with an upwards trend. These cases are of particular interest to emergency medical services (EMS) due to available invasive treatment options like chest tube placement or resuscitative thoracotomy. To date, there is no sufficient data from Austria regarding penetrating chest trauma in a metropolitan area, and no reliable source to base decisions regarding further skill proficiency training on. METHODS: For this retrospective observational study, we screened all trauma emergency responses of the Viennese EMS between 01/2009 and 12/2017 and included all those with a National Advisory Committee for Aeronautics (NACA) score ≥ IV (= potentially life-threatening). Data were derived from EMS mission documentations and hospital files, and for those cases with the injuries leading to cardiopulmonary resuscitation (CPR), we assessed the EMS cardiac arrest registry and consulted a forensic physician. RESULTS: We included 480 cases of penetrating chest injuries of NACA IV-VII (83% male, 64% > 30 years old, 74% stab wounds, 16% cuts, 8% gunshot wounds, 56% inflicted by another party, 26% self-inflicted, 18% unknown). In the study period, the incidence rose from 1.4/100,000 to 3.5/100,000 capita, and overall, about one case was treated per week. In the cases with especially severe injury patterns (= NACA V-VII, 43% of total), (tension-)pneumothorax was the most common injury (29%). The highest mortality was seen in injuries to pulmonary vessels (100%) or the heart (94%). Fifty-eight patients (12% of total) deceased, whereas in 15 cases, the forensic physician stated survival could theoretically have been possible. However, only five of these CPR patients received at least unilateral thoracostomy. Regarding all penetrating chest injuries, thoracostomy had only been performed in eight patients. CONCLUSIONS: Severe cases of penetrating chest trauma are rare in Vienna and happened about once a week between 2009 and 2017. Both incidence and case load increased over the years, and potentially life-saving invasive procedures were only reluctantly applied. Therefore, a structured educational and skill retention approach aimed at both paramedics and emergency physicians should be implemented. TRIAL REGISTRATION: Retrospective analysis without intervention.

30-day and one-year readmission rate in 11,270 patients with surgical treatment for proximal femoral fractures across Austria.

Aims: Patients with proximal femoral fractures (PFFs) are often multimorbid, thus unplanned readmissions following surgery are common. We therefore aimed to analyze 30-day and one-year readmission rates, reasons for, and factors associated with, readmission risk in a cohort of patients with surgically treated PFFs across Austria. Methods: Data from 11,270 patients with PFFs, treated surgically (osteosyntheses, n = 6,435; endoprostheses, n = 4,835) at Austrian hospitals within a one-year period (January to December 2021) was retrieved from the Leistungsorientierte Krankenanstaltenfinanzierung (Achievement-Oriented Hospital Financing). The 30-day and one-year readmission rates were reported. Readmission risk for any complication, as well as general medicine-, internal medicine-, and surgery/injury-associated complications, and factors associated with readmissions, were investigated. Results: The 30-day and one-year readmission rates due to any complication were 15% and 47%, respectively. The 30-day readmission rate (p = 0.001) was higher in endoprosthesis than osteosynthesis patients; this was not the case for the one-year readmission rate (p = 0.138). Internal medicine- (n = 2,273 (20%)) and surgery/injury-associated complications (n = 1,612 (14%)) were the most common reason for one-year readmission. Regardless of the surgical procedure, male sex was significantly associated with higher readmission risk due to any, as well as internal medicine-associated, complication. Advanced age was significantly associated with higher readmission risk after osteosynthesis. In both cohorts, treatment at mid-sized hospitals was significantly associated with lower readmission risk due to any complication, while prolonged length of stay was associated with higher one-year readmission risks due to any complication, as well as internal-medicine associated complications. Conclusion: Future health policy decisions in Austria should focus on optimization of perioperative and post-discharge management of this vulnerable patient population.

The Urgent Need for Nutritional Medical Care in Geriatric Patients-Malnutrition in Nursing Homes.

Patients aged 65 and over who are accommodated in hospitals and nursing homes are at high risk of malnutrition and often show signs of it. The future relevance of this problem becomes clear, especially in view of the demographic development of the coming years and decades. In this study, the correlation between malnutrition, hypoalbuminemia, anemia, elevated CRP, and low transferrin levels, as well as mortality in seniors between 65 and 100 years, should be revealed. Therefore, the prevalence of disease-specific malnutrition (DRM), according to the criteria of the guidelines of the German Society of Nutritional Medicine (DGEM), and the prevalence of hypoalbuminemia were presented based on the data of 120 residents who were inpatients in a large Viennese nursing home between 01/2017 and 08/2020. Moreover, 86 of the inpatient residents were women and 34 were men, with a mean age of 84 years (SD: 8.7). In this examination, more than one-third of nursing home residents were malnourished. More than half of the residents were found to have low serum albumin or low transferrin saturation. However, no correlation between elevated CRP, low transferrin, or low serum albumin values and malnutrition could be established. Residents with low serum albumin or low transferrin levels, however, had a higher mortality rate. This study supports the urgent relevance of closer and individually personalized medical nutritional interventions, especially concerning hypoalbuminemic seniors aged 65 years and older.

Predictive Validity of Mortality after Surgically Treated Proximal Femur Fractures Based on Four Nutrition Scores-A Retrospective Data Analysis.

BACKGROUND: Hip fractures are becoming a growing concern due to an aging population. The high costs to the healthcare system and far-reaching consequences for those affected, including a loss of independence and increased mortality rates, make this issue important. Poor nutritional status is a common problem among geriatric patients and is associated with a worse prognosis. Nutritional screening tools can help identify high-risk patients and enable individualized care to improve survival rates. MATERIAL AND METHODS: This retrospective study investigates four nutritional scores and laboratory parameters' predictive significance concerning postoperative mortality after surgical treatment of proximal femur fractures at 1, 3, 6, and 12 month/s for patients over 60 years using the chi-square test, Cox regression analysis, and receiver operating characteristics (ROC). The European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines were used as part of the screening of the respective nutritional status of the patients, in particular to filter out malnutrition. RESULTS: A total of 1080 patients were included in this study, whereas 8.05% suffered from malnutrition, defined as a body mass index (BMI) below 18.5 kg/m2. The Mini Nutritional Assessment (MNA) screening tool identified the highest proportion of malnourished patients at 14.54%. A total of 36.39% of patients were at risk of malnutrition according to three nutrition scores, with MNA providing the most significant proportion at 41.20%. Patients identified as malnourished had a higher mortality rate, and MNA screening was the only tool to show a significant correlation with postoperative mortality in all survey intervals. The MNA presented the best predictive significance among the screening tools, with a maximum area under the curve (AUC) of 0.7 at 12 month postoperatively. CONCLUSIONS: MNA screening has a solid correlation and predictive significance regarding postoperative mortality-therefore routine implementation of this screening in orthopedic/traumatology wards is recommended. Moreover, nutritional substitution therapy can offer a relatively inexpensive and easy-to-implement measure. The Graz malnutrition screening (GMS) shows moderate predictive power and could be considered as an alternative for patients under 60 years of age. A higher albumin level is associated with improved survival probability, but cannot be indicative of nutritional status.

The Epidemiological Transition of Surgically Treated Proximal Hip Fractures in Austria over the Course of the Pandemic-Back to Normal or a New Normal?

BACKGROUND: The COVID-19 pandemic has had a significant impact on the treatment protocols of orthopedic and trauma departments, but its specific effect on the mortality of hip fracture patients due to possible delays in surgery remains uncertain. This study aimed to investigate whether the COVID-19 pandemic worsened the mortality of patients with hip fractures. MATERIALS AND METHODS: This study included 246 prospectively enrolled patients who suffered from hip fractures during the Austrian State of Emergency period between 1 March and 30 June 2020 and 2021 and were admitted to a tertiary care trauma center. This cohort was compared with a retrospective control group of 494 patients admitted for hip fractures during the same timeframe in 2017, 2018, and 2019. These groups were compared to a prospective recruited "post-COVID-19 collective consisting of the years 2022 and 2023 including 313 patients. RESULTS: This study found a 22% reduction in admissions during the COVID-19 period compared to the pre-COVID period (p = 0.018), as well as significant changes in gender (p = 0.013) and place of accident (p = 0.049). No other changes in demographic variables were observed. The 30-day mortality rate was 14.67% in the pre-COVID period, compared to 15.18% during the COVID-19 period (p = 0.381). No differences were observed in surgical complication rates or in the relationship between comorbidity burden and survival. CONCLUSION: This study did not show a higher perioperative mortality rate due to COVID-19. However, under current circumstances, with potentially reduced surgical and hospital bed capacities, it is expected that this condition might require a high degree of resources in times when resources are potentially scarce, such as during an ongoing pandemic. LEVEL OF EVIDENCE: Level III.

Obesity-related juvenile form of cartilage lesions: a new affliction in the knees of morbidly obese children and adolescents.

OBJECTIVES: Overweight and obesity are afflictions that lead to an increased risk of health problems including joint problems. The aim of the study was to assess the condition of articular cartilage in obese adolescent patients suffering from knee pain. METHODS: MRI of 24 knees of 20 morbidly obese patients, mean age 14.2 years, was performed in an open 1.0 Tesla MR system, where the cartilage, the quality and structure of the menisci, and the presence or absence of surrounding changes was examined. RESULTS: In all patients a cartilage lesion in at least one region of the knee could be detected. Retropatellar cartilage lesions have been found in 19 knees. Ten cartilage lesions grade I, and four lesions grade II have been described in the lateral compartment of the knee, whereas the medial compartment showed in eight cases a grade I, in 13 cases a grade II and in two cases a grade III cartilage lesion. Meniscal changes were assessed in most patients. CONCLUSION: Morbidly obese children and adolescents show major abnormalities in the articular cartilage of the knee. Whether obesity alone is the causal factor for the development of the pattern of these changes, remains to be seen. KEY POINTS: • Morbidly obese children and adolescents often suffer from knee pain • Prospective study showed cartilage and meniscal lesions in morbidly obese adolescents • MRI is an adequate tool for assessing cartilage lesions even in morbidly obese patients • It is unclear whether cartilage abnormalities are mainly due to mechanical overload.

Mortality and Epidemiological Changes in Proximal Hip Fractures in the Course of a Pandemic.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has had an immense impact on the treatment protocols of orthopedic and trauma departments, yet its specific effect on mortality in patients with hip fractures due to possible surgical delays is still unclear. The purpose of this paper was to investigate whether the COVID-19 pandemic worsened the mortality rate of hip fracture patients. PATIENTS AND METHODS: This study comprised 175 prospectively included patients who (1) suffered from hip fractures, (2) presented during the Austrian state of emergency period from 15 March 2020 to 30 May 2021, and (3) were admitted to a level I trauma center. This cohort was compared with a retrospective control group of 339 patients admitted for hip fractures during the same timeframe in 2017, 2018, and 2019. RESULTS: An admission reduction of 22% in the COVID period compared with the pre-COVID period was evident (p = 0.018). The 30-day mortality rate was 14.67% (pre-COVID) compared with 15.18% (p = 0.381). No differences in surgical complication rates or relationships between comorbidity burden and survival were observed. There were no significant changes in demographic variables, except for admission rate, gender (p = 0.013), and place of accident (p = 0.049). CONCLUSION: Surgeons should be reassured to take COVID-19 precautions, as this study did not show higher perioperative mortality due to COVID-19 measures. Under the current circumstances, with possibly reduced surgical and hospital bed capacities, it is expected that hip fractures may continue to require a high degree of resources.

Biomechanical Assessment of Fracture Loads and Patterns of the Odontoid Process.

STUDY DESIGN: Laboratory study. OBJECTIVE: This study aimed to investigate the biomechanical competence and fracture characteristics of the odontoid process. SUMMARY OF BACKGROUND DATA: Odontoid fractures of the second cervical vertebra (C2) represent the most common spine fracture type in the elderly. However, very little is known about the underlying biomechanical fracture mechanisms. MATERIALS AND METHODS: A total of 42 C2 human anatomic specimens were scanned via computed tomography, divided in six groups, and subjected to combined quasistatic loading at -15°, 0°, and 15° in sagittal plane and -50° and 0° in transverse plane until fracturing. Bone mineral density (BMD), height, fusion state of the ossification centers, stiffness, yield load, and ultimate load were assessed. RESULTS: While lowest values for stiffness, yield load, and ultimate load were observed at load inclination of 15° in sagittal plane, no statistically significant differences were observed between the study groups ( P ≥0.235). BMD correlated positively with yield load ( r2 =0.350, P <0.001) and ultimate load ( r2 =0.955, P <0.001) but not with stiffness ( r2 =0.082, P =0.07). The specimens with clearly distinguishable fusion of the ossification centers revealed less data scattering of the biomechanical outcomes. CONCLUSION: Load direction plays a subordinate role in traumatic fractures of the odontoid process. BMD was associated with significant correlation to the biomechanical outcomes. Thus, odontoid fractures appear to result from of an interaction between the load magnitude and bone quality.

Biomechanical evaluation of an allograft fixation system for ACL reconstruction.

The purpose of this study was to compare the biomechanical stability, especially graft slippage of an allograft screw and a conventional interference screw for tibial implant fixation in ACL reconstruction. Twenty-four paired human proximal tibia specimens underwent ACL reconstruction, with the graft in one specimen of each pair fixed using the allograft screw and the other using the conventional interference screw. Specimens were subjected to cyclic tensile loading until failure. The two fixation methods did not show any statistical difference in load at graft slippage (p = 0.241) or estimated mean survival until slippage onset (p = 0.061). The ultimate load and the estimated mean survival until failure were higher for the interference screw (p = 0.04, and p = 0.018, respectively). Graft displacement at ultimate load reached values of up to 7.2 (interference screw) and 11.3 mm (allograft screw). The allograft screw for implant fixation in ACL reconstruction demonstrated comparable behavior in terms of graft slippage to the interference screw but underperformed in terms of ultimate load. However, the ultimate load, occurring at progressive graft slippage, may not be considered a direct indicator of clinical failure.

Effect of daily intake of yoghurt and bread enriched with biologically active substances on blood lipids and vitamin A in adolescents and young adults.

OBJECTIVE: The aim was to investigate whether the daily intake of special nutrients, enriched with supplements from natural origins, has any effect on blood parameters. DESIGN AND SUBJECTS: In this double-blind placebo-controlled clinical trial, 80 healthy subjects (mean age 26.3 years) were statistically assigned to two groups. Group I had to eat two special yoghurt and bread products a day. The other probands represented the control group (II). SETTING: Plasma concentrations of blood parameters were measured at the beginning and at the end of the study, and dietary intake was calculated. RESULTS: In group I, total cholesterol decreased. This was due to a significant drop of low-density lipoprotein-cholesterol from 106.0 to 99.0 mg/dl. A significant reduction of the apolipoprotein B and an increase of vitamin A in group I were also observed. CONCLUSION: Regular intake of specially fortified food influences parameters, especially lipids and lipoproteins.