Portable dynamic ultrasonography is a useful tool for the evaluation of suspected syndesmotic instability: a cadaveric study.

PURPOSE: Portable ultrasonography (P-US) is increasingly used to diagnose syndesmotic instability. The aim of this study was to evaluate syndesmotic instability by measuring the distal tibiofibular clear space (TFCS) in a cadaveric model using P-US with progressive stages of syndesmotic ligamentous transection under external rotation stress. METHODS: Ten fresh lower leg cadaveric specimens amputated above the proximal tibiofibular joint were used. Using P-US, the TFCS was evaluated in the intact stage and after progressive sectioning of the (1) anterior-inferior tibiofibular ligament (AITFL), (2) interosseous ligament (IOL), and (3) posterior-inferior tibiofibular ligament (PITFL). The TFCS was measured in both the unstressed (0 Nm) state and with 4.5, 6.0, 7.5, and 9.0 Nm of external rotation stress using a bone hook placed on the first metatarsal bone at each stage of ligamentous transection stage using both P-US and fluoroscopy. RESULTS: When assessed with P-US, partial syndesmotic injury encompassing the AITFL and IOL resulted in significant TFCS widening at 4.5 Nm of external rotation torque when compared to intact state with a TFCS-opening of 2.6 ± 2 mm, p = 0.01. In contrast, no significant differences in TFCS were detected using fluoroscopy. Only a moderate correlation was found between P-US and fluoroscopy. CONCLUSION: P-US is a useful tool in diagnosing syndesmotic instability during external rotation stress examination. TFCS-opening increased as additional ligaments of the syndesmosis were transected, and application of 4.5 Nm torque was sufficient to detect a difference of 2.6 mm after the IOL cut.

Adequate union rates for the treatment of acute proximal fifth metatarsal fractures.

PURPOSE: To compare the bone healing, clinical, and return to daily activity outcomes after either surgical or conservative management of acute zone 1, 2, and 3 fifth metatarsal fractures. METHODS: A literature search was performed to identify studies published from the earliest record to January 2019 using EMBASE (Ovid), MEDLINE via PubMed, CINAHL, and Web of Science. All articles assessing clinical outcomes of acute proximal fifth metatarsal fractures were included. Bone healing and clinical outcomes were thereafter calculated using a simplified pooling method. RESULTS: Thirty-two articles comprising of a total of 1,239 fractures were included, of which one was a randomized controlled trial, seven were prospective studies, and 24 were retrospective studies. 627 zone 1 fractures demonstrated union rates of 93.2% following conservative treatment and 95.1% following surgical treatment. Conservatively managed zone 1 fractures were displaced 49.5% of the time, compared to a rate of 92.8% for the surgically treated cases. For Jones' (zone 2) fractures, bone healing outcomes of conservative versus surgical treatment showed union rates of 77.4% versus 96.3%, refracture rates of 2.4% versus 2.1%, and mean time to union of 11.0 weeks versus 9.4 weeks, respectively. Only ten proximal diaphyseal (zone 3) fractures were reported, with a mean return to work of 8.2 weeks. CONCLUSION: Acute zone 1 fractures are preferably treated conservatively as similar union rates were found after both conservative and surgical management. In contradistinction, acute zone 2 fractures demonstrate higher union rates and faster time to union when treated surgically. The outcomes of acute zone 3 fractures are rarely reported in the literature, so treatment recommendations remain unclear. Further research of proximal fifth metatarsal fractures is warranted to provide more definitive conclusions, but current findings can aid surgeons during the shared clinical decision making process. LEVEL OF EVIDENCE: IV.

Significance of cutting plane in liquid metal embrittlement severity quantification.

The automotive industry is turning to advanced high strength steels (AHSS) to reduce vehicle weight and increase fuel efficiency. However, the zinc coating on AHSS can cause liquid metal embrittlement (LME) cracking during resistance spot welding. To understand the problem, the severity of the cracking must be measured. Typically, this is done from the weld cross-section. Currently, there is no standard procedure to determine which plane through the weld must be examined to gauge cracking severity, leading to a variety of practices for choosing a cutting plane. This work compares the magnitude and variability of LME severity measured from the plane of exhibiting the most severe surface cracking to arbitrarily chosen planes. The plane exhibiting the most severe cracks had more and longer cracks on the cross-section than the arbitrarily chosen plane, resulting in a higher crack severity measurement. This higher absolute measurement increased the relative accuracy of the examination, allowing for fewer welds to be examined to precisely determine the effect of LME mitigation methods on cracking severity, how welding parameters affect LME cracking severity and the predicted LME affected strength of a particular weld.

Worldwide epidemiology of foot and ankle injuries during military training: a systematic review.

INTRODUCTION: Musculoskeletal foot and ankle injuries are commonly experienced by soldiers during military training. We performed a systematic review to assess epidemiological patterns of foot and ankle injuries occurring during military training. METHODS: A review of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search, done on 14 February 2019, resulted in 1603 reports on PubMed, 565 on Embase and 3 on the Cochrane Library. After reading the remaining full-text articles, we included 91 studies. RESULTS: Among a population of 8 092 281 soldiers from 15 countries, 788 469 (9.74%) foot and ankle injuries were recorded. Among the 49 studies that reported on length of training, there were 36 770/295 040 (18.17%) injuries recorded among women and 248 660/1 501 672 (16.56%) injuries recorded among men over a pooled mean (±SD) training period of 4.51±2.34 months. Ankle injuries were roughly 7 times more common than foot injuries, and acute injuries were roughly 24 times more common than non-acute injuries. Our findings indicated that, during a 3-month training period, soldiers have a 3.14% chance of sustaining a foot and ankle injury. The incidence of foot or ankle injury during military parachutist training was 3.1 injuries per thousand jumps. CONCLUSIONS: Our findings provide an overview of epidemiological patterns of foot and ankle injuries during military training. These data can be used to compare incidence rates of foot and ankle injuries due to acute or non-acute mechanisms during training. Cost-effective methods of preventing acute ankle injuries and non-acute foot injuries are needed to address this problem.

Optimizing surgery of metaphyseal-diaphyseal fractures of the fifth metatarsal: a cadaveric study on implications of intramedullary screw position, screw parameters and surrounding anatomic structures.

AIMS: Many advocate screw fixation of fractures to the metaphyseal-diaphyseal junction of the fifth metatarsal base, better known as Jones fractures (JF), to facilitate quicker ambulation and return to sport. Maximizing screw parameters based on fifth metatarsal (MT5) anatomy, alongside understanding the anatomic structures compromised by screw insertion, may optimize surgical outcomes. This study aims to (1) correlate the proximity of JF to the peroneus brevis (PB) and plantar fascia (PF) footprints and (2) quantify optimal screw parameters given MT5 anatomy. MATERIALS AND METHODS: 3D CT-scan reconstructions were made of 21 cadaveric MT5s, followed by meticulous mapping of the PB and PF onto the reconstructions. Based on bone length, shape, narrowest intramedullary canal (IMC) diameter, and surrounding anatomy, two traditional debated screw positions were modeled for each reconstruction: (1) an anatomically positioned screw (AP), predicated on maximizing screw length by following the IMC for as long as possible, and (2) a clinically achievable screw (CA), predicated on maximizing screw length without violating the fifth tarso-metatarsal joint or adjacent cuboid bone. Fixation parameters were calculated for all models. RESULTS: The PB and PF extended into the JF site in 29% and 43%, respectively. AP's did not affect PB and PF footprint but required screw entry through the cuboid and fifth tarso-metatarsal joint in all specimens. CA screw entry sites, avoiding the cuboid and fifth tarso-metatarsal joint, partially compromised the PB and PF insertions in 33% and 62% with a median surface loss of 1.6%%(range 0.2-3.2%) and 0.81%%(range 0.05-1.6%), respectively. Mean AP screw length was 64±3.6mm and thread length 49±4.2mm. Mean CA screw length was 48±5.8mm and thread length 28±6.9mm. CONCLUSION: This study underscores the challenges associated with surrounding MT5 anatomy as they relate to optimal JF treatment. Both the extent of JF as well as a clinically achievable positioned screw violate the PB and PF footprints - although the degree to which even partial disruption of these footprints has on outcome remains unclear. To minimize damage to surrounding structures, including the PB and PF footprint, while allowing a screw length approximately two thirds of the metatarsal length, the CA screw position is recommended. This position balances the desire to maximize pull out strength while avoiding cortical penetration or inadvertent fracture site distraction.

Diagnosing syndesmotic instability with dynamic ultrasound - establishing the natural variations in normal motion.

BACKGROUND: Syndesmotic instability, when subtle, is challenging to diagnose and often requires visualization of the syndesmosis during applied stress. The primary aim was to assess normal distal tibiofibular motion in the sagittal plane using dynamic ultrasound under stress conditions. The secondary aim was to evaluate the reliability of dynamic stress ultrasonography. METHODS: Twenty-eight participants without history of ankle injury were included. Sagittal fibular translation was generated by applying a manual force to the fibula from anterior to posterior and from posterior to anterior. Distance between the ultrasound probe and the fibula was taken at two predefined points: 1) no force applied and, 2) during maximum force application. Each participant was scanned twice by two independent examiners, and each scan was analysed by two independent examiners. Three participants were scanned a second time by the same examiner who analysed these films twice to assess for intraobserver agreement. Means of exam 1 versus exam 2 were compared using a mixed linear model. Agreement among observers was calculated using intraclass correlation coefficients (ICC) interpreted as 0.4, poor; 0.4 〈 ICC < 0.59, acceptable; 0.6 < ICC < 0.74, good; ICC 〉 0.74, excellent. RESULTS: Fifty-six ankles were included in the study, including 16 (57%) males and 12 (42%) females. Average anterior to posterior fibular sagittal translation was 0.89 ± 0.6 mm and posterior to anterior fibular sagittal translation was 0.49 ± 1.1 mm. Anterior to posterior translation means of exam 1 versus exam 2 showed no significant differences, means of 0.81 mm [0.7-0.9] versus 0.77 mm [0.7-1.0], and posterior to anterior means [95% CI] of 0.42 mm [0.3-0.5] versus 0.44 mm [0.2-0.6] (p-values 0.416 and 0.758, respectively). Excellent Inter- and intraobserver agreement was found for all measurements taken. CONCLUSION: Dynamic ultrasound allows one to effectively and readily evaluate sagittal translation of the distal tibiofibular joint. It is able to afford bilateral comparisons, which becomes critical as the amount of syndesmotic instability approaches greater degrees of subtlety.

Domestic terrorism with chemical or biological agents: psychiatric aspects.

OBJECTIVE: This article highlights the mental health consequences of a domestic terrorist incident involving chemical or biological weapons. METHOD: The author reviews the literature on the neuropsychiatric effects of selected chemical and biological weapon agents, on the psychological sequelae of mass disasters, and on approaches to crisis intervention. RESULTS: Disturbances of behavior, affect, and cognition can result directly from the pharmacological actions of some chemical and biological weapon agents. In addition, an incident involving these agents can have considerable psychological effects on individuals and the community. In either case, some disorders are acute and others are prolonged or delayed in onset. Effective therapeutic intervention involves a broad range of clinical, social, and administrative actions. CONCLUSIONS: Psychiatrists have an important role in the management of a chemical or biological terrorist incident and, along with their other medical colleagues, should train and prepare for it.

Outcome after open reduction and internal fixation of Lisfranc joint injuries.

BACKGROUND: Open reduction and internal fixation has been recommended as the treatment for most unstable injuries of the Lisfranc (tarsometatarsal) joint. It has been thought that purely ligamentous injuries have a poor outcome despite such surgical management. METHODS: We performed a retrospective study of patients who underwent open reduction and screw fixation of a Lisfranc injury in a seven-year period. Among ninety-two adults treated for that injury, forty-eight patients with forty-eight injuries were followed for an average of fifty-two months (range, thirteen to 114 months). Fifteen injuries were purely ligamentous, and thirty-three were combined ligamentous and osseous. Patient outcome was assessed with use of the American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score and the long-form Musculoskeletal Function Assessment (MFA) score. RESULTS: The average AOFAS midfoot score was 77 points (on a scale of 0 to 100 points, with 100 points indicating an excellent outcome), with patients losing points for mild pain, decreased recreational function, and orthotic requirements. The average MFA score was 19 points (on a scale of 0 to 100 points, with 0 points indicating an excellent outcome), with patients losing points because of problems with "leisure activities" and difficulties with "life changes and feelings due to the injury." Twelve patients (25 percent) had posttraumatic osteoarthritis of the tarsometatarsal joints, and six of them required arthrodesis. The major determinant of a good result was anatomical reduction (p = 0.05). The subgroup of patients with purely ligamentous injury showed a trend toward poorer outcomes despite anatomical reduction and screw fixation. CONCLUSIONS: Our results support the concept that stable anatomical reduction of fracture-dislocations of the Lisfranc joint leads to the best long-term outcomes as patients so treated have less arthritis as well as better AOFAS midfoot scores.

Femoral preparation in cemented total hip arthroplasty: reaming or broaching?

Surgical techniques continue to be refined to improve the results of primary cemented total hip arthroplasty. Although there has been much research in the areas of cementation and implant design, little work has specifically addressed how bone preparation can be optimized on the femoral side. On the basis of available scientific data, it appears that the broach-only system has several potential advantages over the traditional ream-and-broach technique. Broaching is usually faster, leaves behind more bone stock, and may improve both microinterlock and macrointerlock. Additionally, the excess bone resulting from broaching without reaming does not seem to compromise fixation at the bone-cement interface. Such differences may become even more important as the indications for cemented hip arthroplasty broaden to include increasingly younger and more active patients, because revision in these individuals is likely. In most cases, reaming is probably counterproductive, although it may be advantageous when used to open the femoral canal, to prevent varus stem orientation, and to manage sclerosis or deformity of bone due to a preexisting hip disorder or the presence of internal fixation devices. Regardless of which method is chosen, good bone surface cleansing and cement penetration remain paramount. More studies comparing reamed and nonreamed preparation are necessary to resolve this controversial issue definitively.

Can the presence of equinus contracture be established by physical exam alone?

The condition in which ankle dorsiflexion is restricted is known as equinus contracture (EC). Equinus contracture is purported to be associated with a number of clinical conditions. However, there are no data to support or refute a clinician's ability to diagnose EC by clinical exam. We prospectively evaluated the maximum ankle dorsiflexion with the knee fully extended in 68 people (34 patients with isolated fore- or midfoot pain and 34 asymptomatic subjects) both by clinical exam and by a custom-designed ankle goniometer. We compared the likelihood of agreement of the clinical impression (equinus, no equinus) to the maximum ankle dorsiflexion measured with the instrument at two different numerical definitions of EC (< or =5 degrees and < or =10 degrees of maximum dorsiflexion). When all subjects were included and equinus defined as < or =5 degrees of ankle dorsiflexion, a clinician's ability to detect the equinus when it is truly present is 77.8%. If equinus is defined as < or =10 degrees, this ability increases to 97.2%. Alternatively, if equinus is not present, as defined by < or =5 degrees, then a clinician's ability to correctly diagnose no equinus is 93.8%. If equinus is defined to < or =10 degrees, this ability decreases to 68.8%.

Arthroscopic evaluation of the subtalar joint: does sinus tarsi syndrome exist?

This is a retrospective review of 49 subtalar arthroscopies performed between 1989 and 1996. Patients were evaluated in the following areas: (1) preoperative diagnosis, (2) preoperative tests and clinical evaluation, (3) intraoperative findings, (4) postoperative diagnosis,(5) complications, and (6) clinical outcome. Particular attention was paid to the accuracy of the preoperative diagnosis, subtalar instability, intraoperative findings in sinus tarsi syndrome, and clinical outcome. Overall, this study demonstrated a success rate of 94% good and excellent results in the treatment of various types of subtalar pathologic conditions with arthroscopic techniques. The Workers' Compensation cases reported 90% good and excellent results. The complication rate was low, with five minor complications reported. The most common complication was a transient neuropraxia involving branches of the superficial peroneal nerve. Of the 14 feet that had a preoperative diagnosis of sinus tarsi syndrome, all the diagnoses were changed at the time of arthroscopy. The postoperative diagnoses included 10 interosseous ligament tears, two cases of arthrofibrosis, and two degenerative joints. Based on these findings, "sinus tarsi syndrome" seems to be an inaccurate term that should be replaced with a specific diagnosis. Arthroscopy is the tool that will allow the orthopaedic surgeon to make a more accurate diagnosis.

Pertinent psychological issues in the immediate management of a weapons of mass destruction event.

Decisions made and actions taken by crisis and consequence managers during the initial stages of a domestic terrorist incident that involves a weapon of mass destruction will influence the ultimate psychological toll of the disaster. Exploring, in advance, the feasibility of quarantine, participating in training exercises that force decision makers to confront the consequences of their decisions on the behaviors of a population at risk from a weapon of mass destruction agent release, and critically examining the capabilities of mental health crisis intervention teams that might respond to a terrorist event are 3 of 12 suggestions offered to crisis and consequence managers to help them prepare for their roles.

Susceptibility of Branhamella catarrhalis to sulphamethoxazole and trimethoprim.

Fifty strains of Branhamella catarrhalis were examined for susceptibility to sulphamethoxazole, trimethoprim and a combination of the two by determinating minimum inhibitory concentrations (MICs) and fractional inhibitory concentrations (FICs). All strains were susceptible to sulphamethoxazole and resistant to trimethoprim. On the basis of the MIC results it was predicted that greater synergy between sulphamethoxazole and trimethoprim would be observed with approximately equal proportions of each component. The lowest FIC values were obtained with a ratio of 1:1 and the greatest synergy was observed at this ratio with 39 strains (78%). Only seven strains were most synergistically inhibited at the ratio of 20:1 (sulphamethoxazole: trimethoprim) although this ratio was still synergic for most strains. Overall the 1:20 ratio was not synergic.

Respiratory tract infections due to Branhamella catarrhalis: epidemiological data from Western Australia.

During a 3-year period Branhamella catarrhalis was isolated in significant numbers from 239 (1.3%) of 19,488 specimens of sputum sent for routine microbiological examination at a 700-bed general hospital. The majority of patients (83%) were over 60 years of age and 65% were male. There was a distinct seasonal variation in isolations with a peak incidence during the winter and early spring, a pattern not found with other pathogens. Susceptibility to amoxycillin decreased by approximately 50% over the 3 years, corresponding to an increased incidence of beta-lactamase-producing strains. There were minimal changes in susceptibility to other antimicrobial agents. Underlying pulmonary disease was the major factor predisposing to B. catarrhalis infection, and 71% of patients were smokers or ex-smokers.

Possibilities for unexplained chronic illnesses among reserve units deployed in Operation Desert Shield/Desert Storm.

Because Armed Forces Reserve members, especially combat support units, were rapidly mobilized during Operation Desert Shield/Desert Storm, they were at higher risk for anxiety and stress-related disorders. Personnel in reserve units in the military force structure are at greater risk for psychologic stress due to rapid mobilization and demobilization, which allows minimal time to process adverse experiences or fears. The unexpected disruption of families and careers and resulting financial pressures are magnified in older age groups who have increased personal and family commitments. Personnel in combat support units are at greatest risk when they lack necessary training, cohesion, and leadership. Prevention efforts in reserve units should involve education regarding the potential for activation and associated disruption of family and career plans. Support networks for reserve families should be encouraged. Additional training in an appropriate context regarding risks of biologic and chemical exposure, with the goal of developing confidence in training and equipment, should be stressed. Finally, group processing before demobilization and recall within 90 days of return to emphasize unit cohesion and readjustment to civilian life may be of benefit.

The safety and efficacy of intraoperative heparin in total hip arthroplasty.

A single dose of unfractionated heparin (15 U/kg), administered intravenously before surgery on the femur suppresses thrombogenesis during total hip replacement. Nine hundred eighty-nine patients (1021 hips) who received one dose of intraoperative heparin with hypotensive epidural anesthesia were followed up prospectively for 3 months. Asymptomatic deep vein thrombosis assessed by ultrasound in the first 198 consecutive patients showed an incidence of 7.1% (14 of 198). The incidence of clinical deep vein thrombosis in the subsequent 791 patients was 0.88% (seven of 791). Symptomatic pulmonary embolism occurred in 0.5% (five of 989). No patients died and there was one major bleeding episode. Based on this favorable experience, intraoperative heparin appears safe and efficacious as thromboembolic prophylaxis.