Ankle Fracture Epidemiology in the United States: Patient-Related Trends and Mechanisms of Injury.

Current nationwide epidemiological data regarding ankle fractures are scarce. Such information is important towards better quantifying the mortality associated with such injuries, financial impact, as well as the implementation of preventative measures. This study evaluated the epidemiology of ankle fractures that occurred during a 5-year period. Specifically, we evaluated demographics, mechanism of injury, and disposition. The National Electronic Injury Surveillance System was queried to identify all patients with ankle fractures that presented to US hospital emergency departments between 2012 and 2016. Census data were used to determine the incidence rates of ankle fractures in terms of age, sex, and race. There was an estimated total of 673,214 ankle fractures that occurred during this period, with an incidence rate of 4.22/10,000 person-years. The mean age of patients with an ankle fracture was 37 ± 22.86 (SD) years; 23.5% of ankle fractures occurred in patients aged 10 to 19 years (7.56/10,000 person-years). In addition, 44% of ankle fractures occurred in men (3.81/10,000 person-years), whereas 56% occurred in women (4.63/10,000 person-years). Data on race/ethnicity were available for 71% of the subjects, with incidence rates of 2.85/10,000 person-years for whites, 3.01/10,000 person-years for blacks, and 4.08/10,000 person-years for others. The most common mechanism of injury was falls (54.83%), followed by sports (20.76%), exercise (16.84%), jumping (4.42%), trauma (2.84%), and other (0.30%). For disposition, 81.84% of patients were treated and released, 1.43% were transferred, 16.01% were admitted, 0.59% were held for observation, and 0.13% left against medical advice. The highest incidence of ankle fractures in men occurred in the 10-to-19-years age group, but women were more commonly affected in all other age groups.

EVALUATION OF PERIOPERATIVE HIGH-SENSITIVE CARDIAC TROPONIN I AS A PREDICTIVE BIOMARKER OF MAJOR ADVERSE CARDIOVASCULAR EVENTS AFTER NONCARDIAC SURGERY.

BACKGROUND: Various studies suggest that perioperative concentrations of high-sensitivity troponins are incremental and predictive factors of a major adverse cardiac event (MACE) and all-cause mortality. OBJECTIVE: The objective of the study was to evaluate the predictive value of high-sensitivity cardiac troponin I (hs-cTnI) in the development of MACE and all-cause mortality, within 30-days and 1-year follow-up after noncardiac surgery. METHODS: In this prospective cohort study, we included men ≥ 45 years and women ≥ 55 years with ≥ 2 cardiovascular risk factors and undergoing intermediate or high-risk noncardiac surgery. Demographic and clinical information was collected from clinical charts. We measured baseline hs-cTnI 24 h before surgery, and its post-operative concentration 24 h after surgery. RESULTS: In the entire sample, 8 patients (8.6%) developed MACE at 30-days follow-up (4 deaths), 12 (12.9%) within the 1st year (7 deaths), and 17 (18.2%) after complete post-surgical follow-up (10 deaths). We observed higher baseline and post-operative concentrations in patients who presented MACE (12 pg/ml vs. 3.5 pg/ml; p = 0.001 and 18.3 pg/ml vs. 5.45 pg/ml; p = 0.009, respectively). The hazard ratios (HRs) calculated by Cox regression analysis between the hs-cTnI baseline concentration and the post-operative development of MACE at 30-days and 1-year were 5.70 (95% confidence interval [CI], 1.10-29.40) with hs-cTnI > 6.2 pg/ml and 12.86 (95% CI, 1.42-116.34) with hs-cTnI > 3.3 pg/ml, respectively. The estimated post-operative HR death risk at 1-year was 14.43 (95% CI, 1.37-151.61) with hs-cTnI > 4.5 pg/ml. CONCLUSIONS: Pre-operative hs-cTnI was an independent predictive risk factor for MACE at 30-days and 1-year after noncardiac surgery and for all-cause mortality at 1-year after noncardiac surgery.

Evaluation of Perioperative High-Sensitive Cardiac Troponin I as a Predictive Biomarker of Major Adverse Cardiovascular Events After Noncardiac Surgery.

BACKGROUND: Various studies suggest that perioperative concentrations of high-sensitivity troponins are incremental and predictive factors of a major adverse cardiac event (MACE) and all-cause mortality. OBJECTIVE: The objective of the study was to evaluate the predictive value of high-sensitivity cardiac troponin I (hs-cTnI) in the development of MACE and all-cause mortality, within 30-days and 1-year follow-up after noncardiac surgery. METHODS: In this prospective cohort study, we included men ≥ 45 years and women ≥ 55 years with ≥ 2 cardiovascular risk factors and undergoing intermediate or high-risk noncardiac surgery. Demographic and clinical information was collected from clinical charts. We measured baseline hs-cTnI 24 h before surgery, and its post-operative concentration 24 h after surgery. RESULTS: In the entire sample, 8 patients (8.6%) developed MACE at 30-days follow-up (4 deaths), 12 (12.9%) within the 1st year (7 deaths), and 17 (18.2%) after complete post-surgical follow-up (10 deaths). We observed higher baseline and post-operative concentrations in patients who presented MACE (12 pg/ml vs. 3.5 pg/ml; p = 0.001 and 18.3 pg/ml vs. 5.45 pg/ml; p = 0.009, respectively). The hazard ratios (HRs) calculated by Cox regression analysis between the hs-cTnI baseline concentration and the post-operative development of MACE at 30-days and 1-year were 5.70 (95% confidence interval [CI], 1.10-29.40) with hs-cTnI > 6.2 pg/ml and 12.86 (95% CI, 1.42-116.34) with hs-cTnI > 3.3 pg/ml, respectively. The estimated post-operative HR death risk at 1-year was 14.43 (95% CI, 1.37-151.61) with hs-cTnI > 4.5 pg/ml. CONCLUSIONS: Pre-operative hs-cTnI was an independent predictive risk factor for MACE at 30-days and 1-year after noncardiac surgery and for all-cause mortality at 1-year after noncardiac surgery.

The chemical composition and events related to the cytotoxic effects of propolis on osteosarcoma cells: A comparative assessment of Colombian samples.

Osteosarcoma (OSA) is a type of bone cancer showing an aggressive biological behavior with metastatic progression. Because propolis potential for the development of new antitumoral drugs has been indicated, we evaluated the chemical composition of Colombian propolis samples and the mechanisms involved in their cytotoxic effects on OSA cells. The chemical composition was analyzed by GC-MS and the DPPH free radical scavenging activity was measured. Cluster and principal components analysis were used to establish an association with their inhibitory concentration 50% (IC50 ). Cell viability was analyzed by MTT assay; apoptosis was determined by flow cytometry; mitochondrial membrane permeability and reactive oxygen species were evaluated by rhodamine 123 and DCFH-DA. Transwell assay was used to evaluate the invasiveness of propolis-treated cells. Samples were grouped: Cluster 1 contained diterpenes and benzophenones and showed the highest antiradical activity; Cluster 2 was characterized by triterpenes, fatty acid, and diterpenes. Usm contained diterpenes and triterpenes different of the other samples and Sil contained triterpenes and flavonoids. Apoptosis, mitochondrial membrane alteration, and suppression of cell invasion were the main mechanisms involved in the inhibition of OSA cells in vitro, suggesting the potential of Colombian propolis to discover new antitumor drugs.

[Chronic recurrent multifocal osteomyelitis in a pediatric patient, a case report]. / Osteomielitis crónica multifocal recurrente en paciente pediátrico, reporte de caso.

INTRODUCTION: Chronic recurrent multifocal osteomyelitis (CRMO) is a very rare disease, of unknown origin that affects primarily the metaphysis of long bones. It is characterized by an insidious onset of symptoms and multiple remissions. The chronicity of symptoms, the diagnostic imaging and the lack of response to first line antibiotic treatment, should be helpful for diagnostic. OBJECTIVE: Present a clinical case, based on clinical, laboratory, radiologic imaging and histopathological results, that ultimately led to the diagnostic of CRMO. CASE REPORT: 9 year old, female patient, with one month of bilateral knee and left ankle arthralgia. Bone Gammagraphy and full body MRI, showed multifocal bone inflammation. These findings led to a biopsy, that turned negative for malignancy and infection. Given all the information available from the laboratory test results, radiologic imaging and histopathological findings, CRMO diagnosis was made. NSAID treatment was order, with good results. CONCLUSIONS: CRMO is a rare disease that even to date and with cutting edge technology, still represents a diagnostic challenge that primarily relies on a high level of suspicion, for a timely and correct treatment.

Eversion Subclavian Endarterectomy and Transposition for Coronary-Subclavian Steal Syndrome in a Patient with Refractory Angina Pectoris.

Late onset of angina pectoris associated with subclavian artery (SA) atherosclerotic occlusive disease is a rare and recognized cause of myocardial ischemia when the lesion is proximal to a left internal mammary artery (LIMA) to coronary bypass. The symptoms typically exacerbate by increasing the flow demand in the extremity; this phenomenon is known as late coronary-subclavian steal syndrome. We describe the case of a 66-year-old woman who underwent coronary artery bypass grafting from the LIMA to the left anterior descending coronary artery in 2000. Years later, she experienced refractory angina pectoris associated to an occlusive lesion in the proximal left SA. SA endarterectomy with eversion technique and subclavian-carotid transposition restored the antegrade flow with resolution of the symptomatology.

The rate of sural nerve violation using the Achillon device: a cadaveric study.

BACKGROUND: Management of acute Achilles tendon rupture remains controversial. Open repair results in lower rerupture rates but is associated with complications from wound healing. Percutaneous and limited open repairs minimize soft tissue complications; however, there is a theoretical increased risk of sural nerve injury. We evaluated the risk of sural nerve violation with the Achillon limited open repair device in cadavers. METHODS: This cadaveric study consisted of 2 parts. The first part evaluated the frequency and location of sural nerve violation using the standard Achillon protocol in 18 intact embalmed left lower limbs. The second part involved device manipulation with 30 degrees of either internal or external rotation in 13 paired, intact embalmed lower limbs. RESULTS: In the first part, 5 of 18 specimens had at least 1 suture passing through the sural nerve. Eight of the 54 needle passes (14.8%) directly pierced the substance of the sural nerve. With internal rotation, 8 of 13 specimens had at least 1 violation of the nerve. Ten of the 39 needle passes (25.6%) directly pierced the substance of the sural nerve. With external rotation, no nerves were violated, significantly decreasing the risk of sural nerve violation versus neutral (P = .038) and internal rotation (P = .001). When sural nerve violation was evaluated in regard to instrument outlet, there was a higher risk in the proximal needle passer (outlet no. 3) compared with the distal needle passer (outlet no. 1) with both neutral testing and internal rotation (P = .027). CONCLUSION: This study demonstrated the potential risk for sural nerve injury using the Achillon device. CLINICAL RELEVANCE: External rotation of the Achillon decreased the rate of sural nerve violation. This may optimize its use in Achilles tendon repairs.

Comparison of Risk Factors and Postoperative Outcomes in Syndesmosis Injuries with Various Ankle Fracture Types.

There is a lack of understanding of risk factors and postoperative outcomes of syndesmotic injuries with singular versus multipart fractures. A retrospective analysis was done between 2008 and 2016, utilizing the American College of Surgeons National Surgical Improvement Program database. Patients with open reduction and internal fixation of isolated lateral malleolus fractures, bimalleolar fractures, or trimalleolar fractures were identified. A total of 2045 patients underwent syndesmotic fixation. Subjects with bimalleolar or trimalleolar fractures were more likely than those with unimalleolar fractures to be Caucasian (odds ratio [OR] = 1.5 and 1.9), female (OR = 1.8 and 2.9), aged > 65 years (OR = 1.6 and 1.9), or have American Society of Anesthesiologists (ASA) classification III (OR =1.5 and 1.4) (all, P ≤ 0.028). Patients with a unimalleolar fracture were more likely than those with a bimalleolar or trimalleolar fracture to be male (OR = 1.8 and 2.9), African American (OR = 1.5 and 1.8), aged < 30 years (OR = 1.4 and 1.8), or present with an ASA I classification (OR = 1.6 and 2.0) (all, P ≤ 0.004). Subjects with bimalleolar or trimalleolar fractures were more likely than those with unimalleolar fractures to have lengthier hospital stays (OR = 1.8 and 2.1), while patients with trimalleolar fractures were more likely than those with unimalleolar fractures to have hypoalbuminemia (OR = 2.3), develop a complication (OR = 2.2) or an open wound (OR = 1.9), or to be readmitted (OR = 2.2) (all, P ≤ 0.036). In this study, comorbidity rates and adverse postoperative outcomes significantly increased as the number-part fractures increased in syndesmotic fixation patients. Risk factors also varied across fracture severity.

Apoptosis-related gene expression induced by Colombian propolis samples in canine osteosarcoma cell line.

BACKGROUND AND AIM: Osteosarcoma (OSA) is the most common bone tumor in canines and humans. This study aimed to assess the cytotoxic and apoptotic effects of Colombian propolis samples on a canine OSA cell line (OSCA-8) by evaluating the expression of BCL-2, BAX, CASPASE 9, CASPASE 8, and TNFR1 genes involved in the apoptosis pathway. MATERIALS AND METHODS: After treating the cells with five Colombian propolis samples (Usm, Met, Fus, Sil, and Caj), we evaluated cell viability and lactate dehydrogenase (LDH) release. Early and late apoptosis was determined by flow cytometry using annexin V/propidium iodide. Furthermore, the effects of three selected samples on gene expression were analyzed by real-time polymerase chain reaction. RESULTS: The Colombian propolis samples reduced OSCA-8 cell viability and increased LDH release. All samples induced apoptosis significantly and upregulated BCL-2 and CASPASE 8 expression. Usm and Sil increased BAX expression, Met and Sil induced CASPASE 9 expression, and Usm increased TNFR1. CONCLUSION: Colombian propolis samples exhibited cytotoxic and apoptotic effects on canine OSA cells, and CASPASE 8 upregulation indicated apoptosis induction by the extrinsic pathway.

Evaluating success rate and comparing complications of operative techniques used to treat chronic syndesmosis injuries.

PURPOSE: To assess the success rate and complications of the surgical interventions used to manage chronic syndesmosis injuries. METHODS: Multiple online databases were queried to identify studies reporting operative intervention for chronic syndesmosis injuries. RESULTS: Modalities of operative fixation include suture-button fixation, arthroscopy and debridement, as well as arthrodesis. The use of operative treatment is effective; however, more direct comparison studies are necessary to evaluate the efficacy of each treatment. CONCLUSION: Various operative procedures have been used for the management of chronic syndesmotic injuries but further prospective studies are necessary to determine the type of treatment that should be indicated.

Excerpts from the documents of Mexican positions and recommendations in cardiovascular diseases and COVID-19.

The recommendations in which the Mexican Society of Cardiology (SMC) in conjunction with the National Association of Cardiologists of Mexico (ANCAM) as well as different Mexican medical associations linked to cardiology are presented, after a comprehensive and consensual review and analysis of the topics related to cardiovascular diseases in the COVID-19 pandemic. Scientific positions are analyzed and responsible recommendations on general measures are given to patients, with personal care, healthy eating, regular physical activity, actions in case of cardio-respiratory arrest, protection of the patient and health personnel as well as precise indications in the use of non-invasive cardiovascular imaging, prescription of medications, care in specific topics such as systemic arterial hypertension, heart failure, arrhythmias and acute coronary syndromes, in addition to emphasizing electrophysiology, interventionism, cardiac surgery and in cardiac rehabilitation. The main interest is to provide the medical community with a general orientation on what to do in daily practice and patients with cardiovascular diseases in the setting of this unprecedented epidemiological crisis of COVID-19.

Se presentan las recomendaciones en las cuales la Sociedad Mexicana de Cardiología (SMC) en conjunto con la Asociación Nacional de Cardiólogos de México (ANCAM), así como diferentes asociaciones médicas mexicanas vinculadas con la cardiología, después de una revisión y análisis exhaustivo y consensuado sobre los tópicos relacionados con las enfermedades cardiovasculares en la pandemia de COVID-19, se analizan posturas científicas y se dan recomendaciones responsables sobre medidas generales a los pacientes, con cuidados personales, alimentación saludable, actividad física regular, acciones en caso de paro cardiorrespiratorio, la protección del paciente y del personal de salud así como las indicaciones precisas en el uso de la imagen cardiovascular no invasiva, la prescripción de medicamentos, cuidados en tópicos específicos como en la hipertensión arterial sistémica, insuficiencia cardiaca, arritmias y síndromes coronarios agudos, además de hacer énfasis en los procedimientos de electrofisiología, intervencionismo, cirugía cardiaca y en la rehabilitación cardiaca. El interés principal es brindar a la comunidad médica una orientación general sobre el quehacer en la práctica cotidiana y pacientes con enfermedades cardiovasculares en el escenario esta crisis epidemiológica sin precedentes de COVID-19.

Rotational Deformity of the First Ray Precludes Accurate Distal Metatarsal Articular Angle Measurement in Hallux Valgus.

The routine workup of hallux valgus includes measurements of the distal metatarsal articular angle (DMAA). However, this angle may not be a reliable measurement when rotational deformities occur. Eight matched cadaveric feet were evaluated radiographically using fluoroscopy. The intermetatarsal angle (IMA), hallux valgus angle, and DMAA were evaluated as a baseline. Then, we assessed whether axial rotation of 15°, 30°, 45°, and 60° affected the accuracy of the IMA and the DMAA significantly. Statistical evaluation was performed using Student's t tests and analysis of variance. The IMA remained stable for each anterior-posterior image despite rotation of the distal segment, with a mean difference of less than 2.5°. However, the DMAA was not constant, having different angles of rotation through the osteotomy site. We were able to demonstrate that measurement of the DMAA varies significantly with rotation of the distal first metatarsal. Using the DMAA to assess first metatarsophalangeal joint congruency should be done cautiously because it may estimate unreliably and inaccurately the 3D deformity often encountered in pathologic hallux valgus.

Cardiac surgery in systemic lupus erythematosus patients: Clinical characteristics and outcomes. / Cirugía cardiaca en pacientes con lupus eritematoso sistémico: características clínicas y desenlaces.

OBJECTIVES: To study the clinical characteristics and outcomes in systemic lupus erythematosus (SLE) patients who underwent cardiac surgery. METHODS: Retrospective analysis of 30 SLE patients who underwent cardiac surgery at a single center. Demographics, comorbidities, clinical and serologic characteristics, cardiovascular risk scores and treatment were recorded. Type of surgery, postoperative complications, mortality and histology were analyzed. RESULTS: Disease duration at surgery was 2 years. Valve replacement was the procedure most frequently performed (53%), followed by pericardial window (37%). At least one postoperative complication developed in 63% (mainly infections). An aortic cross-clamp time≥76minutes was associated with at least one postoperative complication (OR 6.4, 95% CI 1.1-35.4, p=.03). Early death occurred in 5 patients (17%) and late in 3 (10%); main causes were sepsis and heart failure. Disease activity was associated with pericardial window (OR 12.6, 95% CI 1.9-79, p=.007); lymphopenia≤1.200 (OR 10.1, 95% CI 1.05-97, p=.04); age≤30 years (OR 7.7, 95% CI 1.2-46.3, p=.02); and New York Heart Association class III (OR 7.0, 95% CI 1.1-42, p=.03). Postoperative infection was associated with length of hospital stay≥2 weeks (OR 54.9, 95% CI 5.0-602.1, p=.001); intensive care unit stay≥10 days (OR 20, 95% CI 1.6-171.7, p=.01); duration of mechanical ventilation≥5 days (OR 16.9, 95% CI 1.5-171.7, p=.01); and pulmonary artery systolic pressure≥50mmHg (OR 7.8, 95% CI 1.4-41.2, p=.01). CONCLUSIONS: Cardiac surgery in SLE confers high morbidity and mortality. SLE-specific preoperative risk scores should be designed to identify prognostic factors.

A 57 year old man with chronic renal failure and cardiac tamponade who developed ischemic hepatitis.

Ischemic hepatitis is an infrequent entity, usually associated with low cardiac out put. We present a case of a 57 year-old man with chronic renal failure and cardiac tamponade who developed elevation of serum alanine transferase level of 5,054 U/L, aspartate transferase level of 8,747 U/L and lactate dehydrogenasa level of 15,220 U/L. The patient developed hepatic encephalopathy and hypoglycemia. Liver Doppler ultrasound was normal. He was seronegative for HBV and HCV, drugs list was scrutinized for the names of known hepatotoxins. Ischemic hepatitis was diagnosed. The hypoglycemia and encephalopathy were solved and the patient was discharged with normal transaminase levels. Ischemic hepatitis is typically preceded by hypotension, hypoxemia, or both. As one would expect, the most common cause of sustained systemic hypotension is cardiovascular disease. Liver biopsy is usually not necessary. The best treatment is support measures and correct the underlying condition.

[Differential behaviour of blood pressure in patients with neurocardiogenic syncope during the initial stage of the tilt table test]. / Comportamiento diferencial de la tensión arterial de pacientes con síncope neuro-cardiogénico en la fase inicial de la prueba de inclinación.

UNLABELLED: Neurocardiogenic syncope (NCS) is diagnosed by means of a head-up tilt table tests (HUTT). This is a prolonged test although early outcome predictors are known. METHODS: We conducted a study among patients engaged in a syncope study protocol. We performed HUTT in all of them and compared the basal arterial pressure with the arterial pressure at the end of a the 70 degrees tilting. RESULTS: We performed 185 HUTT studies. Systolic blood pressure (BP) raised 0.9% among patients with a negative test, whereas patients with a positive HUTT showed a 2.3% decrease (p = 0.2) in the same measurement. Diastolic BP increased 34% among negative HUTT patients and 14.9% among patients with positive test (p = 0.02). We calculated a relative risk of 1.45 for positive test when the combination of systolic BD decrease and dyastolic increase was present, according to the percentage of change (IC95%: 1.1 to 7.8). CONCLUSIONS: The combination of systolic BP reduction and diastolic BP elevation at the end of the 70 degrees tilting is associated with an increased risk of having a positive HUTT. These changes might be related to differential sympathetic stimulation.

Strength of Syndesmosis Fixation: Two TightRope versus One TightRope with Plate-and-Screw Construct.

Injuries involving the distal tibiofibular syndesmosis can lead to critical destabilization of the ankle mortise. Although specific indications for operative fixation remain unclear, accurate reduction of the syndesmosis has been correlated with the best functional outcomes. The purpose of this study was to evaluate the maximum torque and rotation to failure after fixation with a novel construct. Seven pairs (14 ankles) of embalmed cadaveric lower legs, disarticulated at the knee, were obtained. Each pair was randomly assigned to receive either two TightRopes (Arthrex) or a plate-and-screw construct with one TightRope. All samples were mechanically tested in torsion to determine peak torque, torsional stiffness, and the maximum rotation angle at which failure occurred. Differences between the groups were compared using paired Student's t test. The maximum torque to failure after fixation was not significantly different between the two TightRopes (28.8 N*m; range, 7.3-49.7 N*m) and the one TightRope group (29.5 N*m; range, 9.2-44.9 N*m; p = 0.92). The maximum rotation to fracture after fixation was not significantly different between the two TightRopes (33.3 degrees; range, 21.6-57.0 degrees) and one TightRope group (38.6 degrees; range, 23.0-73.9 degrees). All specimens failed with the fracture of the fibula at the level of the inferior syndesmotic screw. The similar load to failure of the two TightRope and the one TightRope and plate-and-screw plate suggested similar stiffness between the two constructs. The addition of the plate may improve distribution of forces at the level of syndesmosis, reducing stress risers and decreasing the risk of failure, as demonstrated by a lower rotation to failure of the one TightRope with plate-and-screw construct. In addition, this construct is not likely to not be associated with any substantial cost increase. Further clinical studies may further elucidate the role of plate and/or TightRope augmentation to syndesmosis fixation.

A Biomechanical Comparison of Different Tendon Repair Techniques.

Previous studies have examined multiple suture techniques for the repair of ruptured tendons. In this study, we investigated how the two- and four-stranded Krackow suture weave techniques compared with a novel Krackow/Bunnell suture technique. Our hypothesis was that the Krackow/Bunnell suture would have greater strength compared with the two- and four-stranded Krackow suture in terms of resistance to pullout from the muscle tendon. Thirty fresh bovine Achilles tendons were assigned randomly to three groups: (1) two-stranded Krackow, (2) fourstranded Krackow, and (3) the Krackow/Bunnell combination. After suture placement, all specimens were subjected to initial cyclic loading (0-200 N for 200 cycles) and then the tension to failure force defined as the pullout through the muscle tendon was evaluated. Significantly greater deformation before suture failure was seen in the Krackow/Bunnell group compared with the four-stranded Krackow construct (36.2 vs. 28.7 mm, p = 0.009), as well as greater energy required to rupture the suture (4635 vs. 3346 N/mm; p = 0.016). There was no significant difference with regard to the force to failure between the two groups (four-stranded Krackow vs. Krackow/Bunnell). The two-stranded Krackow was found to be inferior to both the four-stranded Krakow and the Krakow/Bunnell techniques with regard to load to failure. We have found that the Krackow/Bunnell suture technique is at least comparable to, if not superior to, the four-stranded Krackow technique with regard to deformation before suture failure and energy required to rupture the tendon. Therefore, the Krackow/Bunnell technique may be an optimal construct if the surgeon is concerned about suture pullout through the tendon; however, future studies evaluating this technique in the clinical setting are required before making any final conclusions for patient use.

World checklist of hornworts and liverworts.

A working checklist of accepted taxa worldwide is vital in achieving the goal of developing an online flora of all known plants by 2020 as part of the Global Strategy for Plant Conservation. We here present the first-ever worldwide checklist for liverworts (Marchantiophyta) and hornworts (Anthocerotophyta) that includes 7486 species in 398 genera representing 92 families from the two phyla. The checklist has far reaching implications and applications, including providing a valuable tool for taxonomists and systematists, analyzing phytogeographic and diversity patterns, aiding in the assessment of floristic and taxonomic knowledge, and identifying geographical gaps in our understanding of the global liverwort and hornwort flora. The checklist is derived from a working data set centralizing nomenclature, taxonomy and geography on a global scale. Prior to this effort a lack of centralization has been a major impediment for the study and analysis of species richness, conservation and systematic research at both regional and global scales. The success of this checklist, initiated in 2008, has been underpinned by its community approach involving taxonomic specialists working towards a consensus on taxonomy, nomenclature and distribution.

Fresh-frozen structural allografts in the foot and ankle.

BACKGROUND: The purpose of this study was to review the results of using structural fresh-frozen femoral head allografts in foot and ankle procedures. These grafts were used in order to restore more normal dimensions of the foot and ankle following surgery or trauma and to treat arthritis or deformity in situations in which conventional cancellous graft would not be sufficient. METHODS: Between January 1995 and December 1998, seventy-five foot and ankle operations were performed with use of structural allograft in seventy-three patients with an average age of forty-six years. The graft was used in conjunction with procedures such as arthrodesis of the subtalar joint (twenty-eight procedures) and osteotomy of the calcaneus (eleven procedures). Risk factors identified preoperatively included diabetes and neuropathy, smoking, osteonecrosis, and multiple previous operations. Each operation was performed in a standard manner, with rigid internal fixation. The mean structural dimension (height or length) of the graft was 1.85 cm. Healing was determined by the absence of swelling and warmth and by the presence of trabeculation across the arthrodesis or osteotomy site on both sides of the allograft as seen radiographically. RESULTS: Healing occurred, at a mean of 4.0 months, after 92% (sixty-nine) of the seventy-five procedures. Once the graft was integrated, there was no evidence of graft resorption or subsidence at a mean of 3.5 years postoperatively. Nine of the seventy-three patients had a superficial wound complication (dehiscence or infection), and a deep infection developed in two patients. CONCLUSIONS: Use of structural allografts is appropriate for reconstructive procedures in the foot and ankle. The grafts may be used successfully, with a relatively low complication rate, in patients with risk factors for less satisfactory bone-healing.

Biomechanical evaluation of varying the number of loops in a repair of a physiological model of Achilles tendon rupture.

BACKGROUND: Numerous suturing techniques have been described to treat Achilles tendon ruptures. No prior studies have evaluated frayed tendon ends on construct strength and whether this allows for less extensile exposure. METHODS: Forty bovine Achilles tendons were divided into groups: 1 control and 4 experimental. Experimental groups were sectioned with ends frayed longitudinally in 2 mm intervals for 2 cm with no fraying for the control group. Four-stand Krackow sutures were used for repairs with 3 loops in the control group, 2 loops in frayed section for experimental groups, and varying numbers of loops (1-4) in healthy tendon. Samples were tested in loading cells at 100 N and 190 N for 1000 cycles. Gap width and maximum load failure were measured. RESULTS: Gapping was <5 mm in controls at 100 N-190 N, significantly lower than experimentals. Greatest gapping occurred in groups with 1-2 loops in healthy tendon (10.9-13.9 mm). Most early catastrophic failures (5/8) occurred in groups with 1-2 loops in healthy tendon. Two failures at 100 N occurred in 1-loop healthy tendons. The least failures occurred in controls (2/8), at 190 N. CONCLUSION: Suture loops incorporated into frayed tendon portions predisposed repairs to significantly greater gapping and lower maximal failure forces than 4-strand Krackow repairs in unfrayed tendons. CLINICAL RELEVANCE: We cannot recommend attempting more limited exposures with sutures in frayed tendon as this may lead to early repair failure. We provided a physiologic model utilizing frayed tendon ends that resembles in vivo Achilles tendon rupture.