bluuebunny/crossref_metadata_2025 huggingface dataset:
Associations between physiotherapy findings and subsequent diagnosis of pelvic or hindlimb fracture in racing Thoroughbreds
Authors: HESSE K. L. , VERHEYEN K. L. P.
Published: October 2010

Reasons for performing study: Physiotherapists who work in racehorse training yards routinely treat horses' backs and hindquarters and may be able to recognise signs that indicate the presence of (impending) pelvic or hindlimb fracture before it becomes catastrophic.

Objective: To establish whether physiotherapy assessment findings in Thoroughbred racehorses referred for routine physiotherapy could be predictive of subsequent (within 30 days) pelvic or hindlimb fracture diagnosis.

Methods: Retrospective veterinary and physiotherapy data from a cohort of Newmarket (UK) Thoroughbred racehorses, were used. A case‐control study compared physiotherapy assessment findings of racehorses with and without a subsequently diagnosed pelvic or hindlimb fracture. Uni‐ and multivariable logistic regression was used to investigate and quantify the strength of association between physiotherapy findings and subsequent fracture diagnosis. Statistical significance was set at P<0.05.

Results: A total of 513 horses provided 14 fracture cases for analysis. Presence of pelvic bony asymmetry, muscle atrophy of the quarters, reduced reflex movements of dorsi‐ and/or ventroflexion and spasm or tenderness on palpation of the gluteal muscles were significantly associated with subsequent fracture diagnosis in univariable analysis. Multivariable analysis indicated that horses subsequently diagnosed with pelvic or hindlimb fracture were 11.1 times more likely to show pelvic bony asymmetry, 4.7 times more likely to display muscle atrophy of the quarters and 6.6 times more likely to have spasm or tenderness on palpation of the gluteal muscles than those that were not.

Conclusions: Racehorses presented for physiotherapy that show pelvic bony asymmetry, muscle atrophy of the quarters and/or spasm or tenderness on palpation of the gluteal muscles should alert the physiotherapist to the potential presence of (impending) pelvic or hindlimb fracture.

Potential relevance: Earlier detection of (impending) pelvic or hindlimb fracture in racing Thoroughbreds could reduce the incidence of catastrophic fractures.
Hindlimb response to tactile stimulation of the pastern and coronet
Authors: CLAYTON H. M. , WHITE A. D. , KAISER L. J. , NAUWELAERTS S. , LAVAGNINO M. , STUBBS N. C.
Published: October 2010

Reasons for performing study:Lightweight tactile stimulators attached to the hind pasterns increase the height of the hind hoof flight arc but details of the induced changes in swing phase kinematics and kinetics have not been investigated.

Hypotheses:Stimulators on the hind pasterns are associated with increased hindlimb joint flexions and increased positive work performed by the hip and tarsal musculature.

Materials and methods:Nine nonlame horses trotted 4 times with and without 55 g tactile stimulators loosely attached around the hind pasterns. Height of the flight arc and peak flexion angles of the hindlimb joints were measured and net positive and negative work performed across each joint during the swing phase were calculated using inverse dynamics analysis and compared across paired conditions.

Results:Speed and stride duration did not change but stimulators were associated with a reduction in hind stance duration. The flight arc was higher with stimulators due to increased flexions of the stifle, tarsal, metatarsophalangeal and distal interphalangeal joints. Positive work increased in the tarsal musculature, but not in the hip musculature, and negative work increased across the stifle, metatarsophalangeal and distal interphalangeal joints.

Potential relevance:The effects of tactile stimulation of the hind pasterns on joint motion and muscle activation may be used in physiotherapy and rehabilitation to restore or increase flexion of the hindlimb joints with the exception of the hip joint. The ability to stimulate concentric activity of the tarsal musculature may have therapeutic applications in conditions such as toe dragging.
Orally administered doxycycline accumulates in synovial fluid compared to plasma
Authors: SCHNABEL L. V. , PAPICH M. G. , WATTS A. E. , FORTIER L. A.
Published: October 2010

Reasons for performing study:Tetracycline compounds have been used to slow the progression of osteoarthritis (OA) and rheumatoid arthritis but the concentration of doxycycline attained in synovial fluid following oral, low‐dose administration has yet to be determined.

Objective:To determine the concentration of doxycycline in synovial fluid following oral, low‐dose administration.

Methods:Six mature horses received doxycycline (5 mg/kg bwt q. 12 h for 5 doses). Venous blood and synovial fluid samples were collected at t = 0, 0.25, 0.5, 1, 12, 24, 48 and 72 h. Doxycycline concentrations were measured using reverse phase high pressure liquid chromatography with ultraviolet detection.

Results:Doxycycline concentrations at all time points after t = 0 were above the lower limit of quantification for the assay. Plasma concentrations of doxycycline were above 0.21 µg/ml at t = 0.5 h. The mean ± s.d. peak concentration (Cmax) of doxycycline in plasma was 0.37 ± 0.22 µg/ml and time to peak concentration was 0.54 ± 0.19 h. Synovial fluid concentrations of doxycycline were above 0.12 µg/ml 1 h after drug administration. The mean Cmaxof doxycycline in the synovial fluid was 0.27 ± 0.10 µg/ml. The penetration factor of doxycycline from plasma into synovial fluid, as determined by a ratio of the area‐under‐the‐curve for synovial fluid:plasma during the sampling period, was 4.6.

Potential relevance:Orally administered doxycycline distributes easily into synovial fluid with a penetration factor of 4.6. Terminal half‐life of the drug in synovial fluid was longer than in the plasma, indicating possible accumulation in this compartment. Furtherin vivostudies are warranted to define a medication protocol prior to routine clinical use of doxycycline for the treatment of OA.
Myositis Ossificans  A Case Report
Authors: Sultana F , Quddus MA , Rahman MM , Nuruzzaman SM
Published: October 2010

Myositis Ossificans is classified into three types: progressive, post traumatic and paraplegic. The progressive form, myositis ossoificans congenita, is a hereditary disease which is usually autosomal dominant or an isolated mutation and more common in boys. Post-traumatic myositis is found following massive trauma and paraplegic myositis occurs below the level of paralysis. Here, a heterotopic bone formation is evident in the muscle or soft tissue, which can occur almost anywhere in the body. An incidental case of myositis ossificans was found in the Department of Radiology & Imaging, Dhaka Medical College Hospital, Dhaka in March, 2009. A male patient of 22 years of age was sent for radiological investigations from the medicine out patient department (MOPD) of Dhaka Medical College Hospital, Dhaka having complaints of backache and pain in the neck and chest. He was diagnosed as a case of myositis ossificans after the radiological report. It was an incidental finding having no history of trauma or familial predisposition. This case is presented for journal record and academic interest. Key words: Myositis Ossificans; autosomal dominant. DOI: 10.3329/jdmc.v18i1.6312 J Dhaka Med Coll. 2008; 18(1) : 79-81
Ontology-Based Information Behaviour to Improve Web Search
Authors: Calegari Silvia , Pasi Gabriella
Published: October 2010

Web Search Engines provide a huge number of answers in response to a user query, many of which are not relevant, whereas some of the most relevant ones may not be found. In the literature several approaches have been proposed in order to help a user to find the information relevant to his/her real needs on the Web. To achieve this goal the individual Information Behavior can been analyzed to ’keep’ track of the user’s interests. Keeping information is a type of Information Behavior, and in several works researchers have referred to it as the study on what people do during a search on the Web. Generally, the user’s actions (e.g., how the user moves from one Web page to another, or her/his download of a document, etc.) are recorded in Web logs. This paper reports on research activities which aim to exploit the information extracted from Web logs (or query logs) in personalized user ontologies, with the objective to support the user in the process of discovering Web information relevant to her/his information needs. Personalized ontologies are used to improve the quality of Web search by applying two main techniques: query reformulation and re-ranking of query evaluation results. In this paper we analyze various methodologies presented in the literature aimed at using personalized ontologies, defined on the basis of the observation of Information Behaviour to help the user in finding relevant information.
Family Pet Ownership during Childhood: Findings from a UK Birth Cohort and Implications for Public Health Research
Authors: Westgarth Carri , Heron Jon , Ness Andy R. , Bundred Peter , Gaskell Rosalind M. , Coyne Karen P. , German Alexander J. , McCune Sandra , Dawson Susan
Published: October 2010

In developed nations, approximately half of household environments contain pets. Studies of Human-Animal Interaction (HAI) have proposed that there are health benefits and risks associated with pet ownership. However, accurately demonstrating and understanding these relationships first requires a better knowledge of factors associated with ownership of different pet types. A UK birth cohort, the Avon Longitudinal Study of Parents and Children (ALSPAC), were used to collect pet ownership data from the mothers, from gestation to child age 10 years old. 14,663 children were included in the study, of which mothers of 13,557 reported pet information at gestation, and 7,800 by age 10. Pet types recorded include cat, dog, rabbit, rodent, bird, fish and tortoise/turtle. The dataset also contains a number of demographic, socioeconomic and behavioural variables relevant to human health behaviour. Logistic regression was used to build multivariable models for ownership of each pet type at age 7 years. Family pet ownership increased during childhood, in particular rabbits, rodents and fish. A number of socioeconomic and demographic factors were associated with ownership of different pet types and the effects differed depending on the pet type studied. Variables which require consideration by researchers include gender, presence of older siblings, ethnicity, maternal and paternal education, maternal and paternal social class, maternal age, number of people in the household, house type, and concurrent ownership of other pets. Whether the mother had pets during her childhood was a strong predictor of pet ownership in all models. In HAI studies, care should be taken to control for confounding factors, and to treat each pet type individually. ALSPAC and other similar birth cohorts can be considered a potential resource for research into the effects of pet ownership during childhood.
Mechanisms of the Gastric Antiulcerogenic Activity of Anacardium humile St. Hil on Ethanol-Induced Acute Gastric Mucosal Injury in Rats
Authors: Luiz-Ferreira Anderson , Almeida Ana Cristina Alves de , Cola Maíra , Barbastefano Victor , Almeida Ana Beatriz Albino de , Batista Leônia Maria , Farias-Silva Elisângela , Pellizzon Cláudia Helena , Hiruma-Lima Clélia Akiko , Santos Lourdes Campaner , Vilegas Wagner , Brito Alba Regina Monteiro Souza
Published: October 2010

Leaves and bark infusions Anacardium humile St. Hil. (Anacardiaceae), known as in Brazil as “cajuzinho do cerrado”, have been used in folk medicine as an alternative treatment for ulcers and gastritis. This study evaluated the gastroprotective activity of an ethyl acetate extract of the leaves of A. humile (AcF) and the mechanism involved in this gastroprotection. Pretreatment concentrations (50, 100, 200 mg.kg−1) were administered by gavage. Following a 60 min. period, all the rats were orally administered 1 mL of absolute ethanol. One hour after the administration of ethanol, all groups were sacrificed, and the gastric ulcer index was calculated. Prostaglandin PGE2 concentration, gastric adherent mucous, and the participation of nitric oxide (NO) and sulfhydryl compounds in the gastroprotection process were also analyzed using the most effective tested dose (50 mg·kg−1). A histological study of the glandular stomach for the evaluation of the epithelial damage and mucus content was also performed. AcF significantly reduced the gastric damage produced by ethanol. This effect was statistically significant for the 50 mg·kg−1 group compared to control. Also, it significantly increased the PGE2 (by 10-fold) and mucous production, while pretreatment with NG-nitro-L-arginine methyl ester (L-NAME) or N-ethylmaleimide (NEM) completely abolished the gastroprotection. AcF has a protective effect against ethanol, and this effect, might be due to the augmentation of the protective mechanisms of mucosa.
Small Interfering RNA Effectively Inhibits the Expression of SARS Coronavirus Membrane Gene at Two Novel Targeting Sites
Authors: Wang Ying , Cao Ying-Li , Yang Fan , Zhang Yun , Wang Shu-Hui , Liu Li
Published: October 2010

Small interfering RNA (siRNA) is a class of duplex RNA molecules of 21-25 nt nucleotides in length functioning post-transcriptionally to downregulate targeted gene expression. The membrane (M) protein of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is highly abundant during viral infections and is a critical element for viral assembly. Nucleotide substitution in the viral genome occurs frequently during SARS-CoV infection. In the current study, we analyzed the M gene sequences derived from 15 SARS-CoV isolates and uncovered six nucleotide substitutions among these isolates. Interestingly, these nucleotide substitutions are all located at the 5’ half of the M gene. Based on this information and previous reports, we created two novel siRNAs targeting two unexploited and well conserved regions in the M gene. The effects of these two siRNAs were tested by semi-quantitative RT-PCR and EGFP-M fusion gene expression. The results demonstrated that both siRNAs effectively and specifically blocked the targeted gene expression. Real time quantitative RT-PCR (qRT-PCR) revealed that siRNA targeting the 3’ half of the M gene (si-M2) induced more potent inhibition than that targeting the 5’ half (si-M1). Both si-M1 and si-M2 significantly downregulated M gene mediated upregulation of interferon b expression. Thus, our results indicate that SARS-CoV M gene specific siRNA might function in a sequence-dependent manner.
Biomedical Use of Isothermal Microcalorimeters
Authors: Braissant Olivier , Wirz Dieter , Göpfert Beat , Daniels A.U.
Published: October 2010

Isothermal microcalorimetry is becoming widely used for monitoring biological activities in vitro. Microcalorimeters are now able to measure heat production rates of less than a microwatt. As a result, metabolism and growth of relatively small numbers of cultured bacteria, protozoans, human cells and even small animals can be monitored continuously and extremely accurately at any chosen temperature. Dynamic effects on these organisms of changes in the culture environment—or of additions to it—are easily assessed over periods from hours to days. In addition microcalorimetry is a non-destructive method that does not require much sample preparation. It is also completely passive and thus allows subsequent evaluations of any kind on the undisturbed sample. In this review, we present a basic description of current microcalorimetry instruments and an overview of their use for various biomedical applications. These include detecting infections, evaluating effects of pharmaceutical or antimicrobial agents on cells, monitoring growth of cells harvested for tissue eingineering, and assessing medical and surgical device material physico-chemical stability and cellular biocompatibility.
Sensor Data Fusion for Accurate Cloud Presence Prediction Using Dempster-Shafer Evidence Theory
Authors: Li Jiaming , Luo Suhuai , Jin Jesse S.
Published: October 2010

Sensor data fusion technology can be used to best extract useful information from multiple sensor observations. It has been widely applied in various applications such as target tracking, surveillance, robot navigation, signal and image processing. This paper introduces a novel data fusion approach in a multiple radiation sensor environment using Dempster-Shafer evidence theory. The methodology is used to predict cloud presence based on the inputs of radiation sensors. Different radiation data have been used for the cloud prediction. The potential application areas of the algorithm include renewable power for virtual power station where the prediction of cloud presence is the most challenging issue for its photovoltaic output. The algorithm is validated by comparing the predicted cloud presence with the corresponding sunshine occurrence data that were recorded as the benchmark. Our experiments have indicated that comparing to the approaches using individual sensors, the proposed data fusion approach can increase correct rate of cloud prediction by ten percent, and decrease unknown rate of cloud prediction by twenty three percent.
Depth Profiling (ICP-MS) Study of Toxic Metal Buildup in Concrete Matrices: Potential Environmental Impact
Authors: Elkadi Mirella , Pillay Avin , Fok Sai Cheong , Feghali Fadi , Bassioni Ghada , Stephen Sasi
Published: October 2010

This paper explores the potential of concrete material to accumulate toxic trace elements using ablative laser technology (ICP-MS). Concrete existing in offshore structures submerged in seawater acts as a sink for hazardous metals, which could be gradually released into the ocean creating pollution and anoxic conditions for marine life. Ablative laser technology is a valuable tool for depth profiling concrete to evaluate the distribution of toxic metals and locate internal areas where such metals accumulate. Upon rapid degradation of concrete these “hotspots” could be suddenly released, thus posing a distinct threat to aquatic life. Our work simulated offshore drilling conditions by immersing concrete blocks in seawater and investigating accumulated toxic trace metals (As, Be, Cd, Hg, Os, Pb) in cored samples by laser ablation. The experimental results showed distinct inhomogeneity in metal distribution. The data suggest that conditions within the concrete structure are favorable for random metal accumulation at certain points. The exact mechanism for this behavior is not clear at this stage and has considerable scope for extended research including modeling and remedial studies.
Diversity and Impact of Prokaryotic Toxins on Aquatic Environments: A Review
Authors: Valério Elisabete , Chaves Sandra , Tenreiro Rogério
Published: October 2010

Microorganisms are ubiquitous in all habitats and are recognized by their metabolic versatility and ability to produce many bioactive compounds, including toxins. Some of the most common toxins present in water are produced by several cyanobacterial species. As a result, their blooms create major threats to animal and human health, tourism, recreation and aquaculture. Quite a few cyanobacterial toxins have been described, including hepatotoxins, neurotoxins, cytotoxins and dermatotoxins. These toxins are secondary metabolites, presenting a vast diversity of structures and variants. Most of cyanobacterial secondary metabolites are peptides or have peptidic substructures and are assumed to be synthesized by non-ribosomal peptide synthesis (NRPS), involving peptide synthetases, or NRPS/PKS, involving peptide synthetases and polyketide synthases hybrid pathways. Besides cyanobacteria, other bacteria associated with aquatic environments are recognized as significant toxin producers, representing important issues in food safety, public health, and human and animal well being. Vibrio species are one of the most representative groups of aquatic toxin producers, commonly associated with seafood-born infections. Some enterotoxins and hemolysins have been identified as fundamental for V. cholerae and V. vulnificus pathogenesis, but there is evidence for the existence of other potential toxins. Campylobacter spp. and Escherichia coli are also water contaminants and are able to produce important toxins after infecting their hosts. Other bacteria associated with aquatic environments are emerging as toxin producers, namely Legionella pneumophila and Aeromonas hydrophila, described as responsible for the synthesis of several exotoxins, enterotoxins and cytotoxins. Furthermore, several Clostridium species can produce potent neurotoxins. Although not considered aquatic microorganisms, they are ubiquitous in the environment and can easily contaminate drinking and irrigation water. Clostridium members are also spore-forming bacteria and can persist in hostile environmental conditions for long periods of time, contributing to their hazard grade. Similarly, Pseudomonas species are widespread in the environment. Since P. aeruginosa is an emergent opportunistic pathogen, its toxins may represent new hazards for humans and animals. This review presents an overview of the diversity of toxins produced by prokaryotic microorganisms associated with aquatic habitats and their impact on environment, life and health of humans and other animals. Moreover, important issues like the availability of these toxins in the environment, contamination sources and pathways, genes involved in their biosynthesis and molecular mechanisms of some representative toxins are also discussed.
An Integrated Assessment of Investments towards Global Water Sustainability
Authors: Bassi Andrea M. , Tan Zhuohua , Goss Sophie
Published: October 2010

To date there has been limited research on integrated water resource management, specifically regarding investments, from a global perspective, largely due to the complexity of the problem and to generally local water management practices. Water demand and supply are very often affected by international factors and with global climate change, population growth and increasing consumption, water management is now more than ever a global issue. This paper gives an overview of current and impending water problems while assessing investment needs for integrated water management as a possible solution to projected water challenges. The analysis compares a business as usual case (BAU) to a scenario in which investments improve water efficiency use across sectors to curb demand, increase innovative supply from desalination and enhance conventional water resources management measures. System dynamics modeling is employed to represent the structural factors influencing water demand and supply in the context of an integrated framework including cross-sectoral linkages. The analysis confirms that sustainable water management is feasible, but it requires investments in the range of $145 billion per year between 2011 and 2050 (0.16% of GDP or $17/person/year) and timely, effective action.
Shifting Workplace Behavior to Inspire Learning: A Journey to Building a Learning Culture
Authors: Schoonbeek Sue , Henderson Amanda
Published: October 2010

This article discusses the process of building a learning culture. It began with establishing acceptance and connection with the nurse unit manager and the ward team. In the early phases of developing rapport, bullying became apparent. Because bullying undermines sharing and trust, the hallmarks of learning environments, the early intervention work assisted staff to recognize and counteract bullying behaviors. When predominantly positive relationships were restored, interactions that facilitated open communication, including asking questions and providing feedback—behaviors commensurate with learning in the workplace—were developed during regular in-service sessions. Staff participated in role-play and role modeling desired behaviors. Once staff became knowledgeable about positive learning interactions, reward and recognition strategies began to reinforce attitudes and behaviors that align with learning. Through rewards, all nurses had the opportunity to be recognized for their contribution. Nurses who excelled were invited to become champions to continue engaging the key stakeholders to further build the learning environment.
Primary Resection of the Posterior Cruciate Ligament Does not Produce a Gap Mismatch in the Navigated Gap Technique
Authors: Matziolis Georg , Perka Carsten
Published: October 2010

Treatment of the posterior cruciate ligament (PCL) is a matter of continued controversy in total knee arthroplasty. By using so-called cruciate ligament–substituting implant designs, retention and resection of the PCL produce equivalent clinical results. However, it remains unclear whether primary resection of the PCL leads to relevant instabilities of the flexion gap. Especially when the increasingly popular navigated gap technique is used, this would result in a nonanatomic size selection and positioning of the femoral component and thus compromise the clinical outcome. The objective of this retrospective study was therefore to determine whether the navigated gap technique leads to a mismatch of the flexion and extension gap in primary routine resection of the PCL. In 92 patients consecutively enrolled in this study (92 knees), the flexion and extension gap were determined and documented after tibial resection, using the navigated gap technique navigation system (OrthoPilot 4.0; B. Braun Aesculap, Tuttlingen, Germany). The flexion gap was 10.4±2.6 (2.5–19.5) mm; the extension gap was 10.4±2.4 (5.5–17.5) mm. The individual difference was normally distributed around 0.0±2.9 (−7 to 7) mm. In the navigated gap technique, primary routine resection of the PCL does not lead to a mismatch of the flexion and extension gap, so that a systematic nonanatomic resection of the femur can be ruled out.
Acetabular Center Axis: Is It the Future of Hip Navigation?
Authors: Hakki Sam , Bilotta Victor , Oliveira J. Daniel , Dordelly Luis
Published: October 2010

There are 2 distinct methods of cup navigation in total hip arthroplasty. One predicts orientation of the acetabulum through bony landmarks outside the acetabulum (eg, the anterior pelvic plane); its unreliability is well published. The other identifies acetabular center axis (ACA) and is patient-specific method that is independent of pelvic tilt, making it more reliable. Data from readily palpable acetabular registration points were compared with postoperative pelvic computed tomography images in 137 cases. Findings show that ACA software is accurate in determining acetabular/cup version and inclination. Cup center axis should coincide within 4 mm of ACA to minimize impingement and maximize stability without altering preoperative femoral version.
Computer-Assisted High Tibial Osteotomy: Preliminary Results
Authors: Iorio Raffaele , Vadalà Antonio , Giannetti Silvio , Pagnottelli Marco , Di Sette Priscilla , Conteduca Fabio , Ferretti Andrea
Published: October 2010

Open-wedge high tibial osteotomy (HTO) is an established technique for the treatment of symptomatic varus malaligned knees. In this study, we prospectively followed up 13 patients (14 knees) who underwent navigation system–supported HTO for varus knee deformity. Preoperatively all patients underwent a physical examination, and anteroposterior and laterolateral lower limb weight-bearing digital radiographs were obtained. The following parameters were examined: (1) Insall-Salvati index; (2) posterior tibial slope angle; (3) mechanical femorotibial angle; (4) inferior limb length. At a mean follow-up of 12.6 months, clinical examination showed satisfactory results in all patients. The mean Modified Cincinnati Rating System Questionnaire rating increased significantly from 46.5±7.2 to 84.6±8, while the mean Knee Society Score increased significantly from 51.4±9.9 to 85.1±7.3. The mean Insall-Salvati index changed from 1.11 preoperatively to 1.10 postoperatively (
P
=.742). According to the navigation system data, the femorotibial mechanical axis was corrected from a varus of 6.3°±1.9° to a valgus of 2.1°±1.6°. These data matched postoperative radiographic lower limb weight-bearing data. In the group of patients in whom we evaluated the posterior tibial slope with the navigation system, we detected an increase of 0.3°±0.4° compared with the preoperative radiographic examination evaluations; the comparison between the postoperative and the preoperative radiograhic examination results showed an increase of 0.5°±0.7° (
P
=.87). The results of our study seem to show greater accuracy of mechanical axis correction and smaller increase in tibial slope when a navigation system is used in open-wedge HTO.
Navigated Revision TKR: A Comparative Study with Conventional Instruments
Authors: Jenny Jean-Yves , Diesinger Yann
Published: October 2010

We selected 86 cases for the study: 50 navigated revision total knee replacements (TKRs) and 36 conventional revision TKRs. We hypothesized that the rate of satisfactory implantation would be higher for navigated revision TKR than for conventional revision TKR. The primary criterion was the rate of optimally implanted prostheses on postoperative anteroposterior and lateral long leg radiographs. Thirty-one navigated cases (62%) and 14 conventional cases (39%) had an optimal global implantation (
P
<.05). The use of a standard navigation software for revision TKR allows a significant improvement of the accuracy of implantation. However, development of dedicated software will allow addressing more precisely the specific features of a revision TKR, such as stem extension navigation, defects filling, and joint line reconstruction.
Computer Modeling to Predict Effects of Implant Malpositioning During TKA
Authors: Mihalko William M. , Williams John L.
Published: October 2010

Computer-assisted surgery has focused on alignment of implants and soft tissue balancing but the end results during surgery as they pertain to long-term function of the implants are not yet realized. One parameter that continues to be variable despite the use of computer navigation is the placement of the implants in the transverse plane. The objective of this study was to determine whether implant and anatomic registrations could be used in a computer model (LifeMOD/KneeSIM, LifeModeler, Inc., San Clemente, California) to show differences in the resulting contact patterns of the medial and lateral condyles of the polyethylene insert. The simulations included tibiofemoral and patellofemoral contact, passive soft tissue (medial and lateral collateral, and posterior cruciate ligaments, as well as the capsular tissues), and active muscle elements (quadriceps and hamstrings). Components of a fixed-bearing cruciate-retaining total knee (Columbus knee system; B. Braun Aesculap, Tuttlingen, Germany) were imported into the model. The systems were subjected to one 60-second cycle of a lunge. Both the femoral and the tibial components were positioned in 5° of internal or external rotation in varying combinations and the resulting kinematics analyzed. The resulting kinematics showed variations in anteroposterior translation of the lateral and medial femoral condyles that resembled several of those reported in the literature for individual patients with a cruciate-retaining knee implant system.
Navigated Knee Kinematics After Tear of the ACL and Its Secondary Restraints: Preliminary Results
Authors: Monaco Edoardo , Maestri Barbara , Labianca Luca , Speranza Attilio , Kelly Matthew James , D’Arrigo Carmelo , Ferretti Andrea
Published: October 2010

In this study we evaluated the role of the anterior cruciate ligament (ACL) and its secondary restraint in controlling knee stability using a navigation system. The purpose of this study was to evaluate the kinematics of the knee in different conditions of instability: ACL intact, after transection of the posterolateral (PL) bundle, after transection of the anteromedial (AM) bundle, and after lesion of the anterolateral femorotibial ligament (ALFTL). Anterior tibial translation and rotation were measured with a computer navigation system in 6 knees in whole fresh-frozen human cadavers by use of a manual maximum load. Anterior translation was evaluated at 30°, 60°, and 90° of flexion; rotation at 0°, 15°, 30°, 45°, 60°, and 90° of flexion. Cutting the PL bundle does not increase anterior translation and rotation of the knee. Cutting the AM bundle significantly increased the anteroposterior (AP) translation at 30° and 60° of flexion (
P
=.01), but does not increase rotation of the knee. Cutting the ALFTL increased anterior translation at 60° of flexion (
P
=.04) and rotation at 30°, 45°, and 60° of flexion (
P
=.03). The PL bundle does not affect anterior translation and rotation of the knee. The AM bundle is the primary restraint of the anterior translation but does not affect rotation of the knee. The lateral compartment becomes the primary restraint of rotation after ACL cut. The primary kinematic effect of an ACL injury is an increase in anterior tibial translation, but there is no significant change in maximum internal or external rotation. The lesion of the ALFTL increases tibial rotation and could be correlated to the pivot shift phenomenon.
Comparison of Intraoperative Stability in ACL Reconstruction Based on Femoral Tunnel Positions
Authors: Park Ju Kwon , Song Eun Kyoo , Seon Jong Keun
Published: October 2010

This study evaluated and compared the intraoperative stabilities using the low and high femoral tunnel techniques in ACL reconstruction. Seventy patients who underwent ACL reconstruction were equally allocated to low or high femoral tunnel groups (35 in the low femoral tunnel group and 35 in the high femoral tunnel group) for this study. The authors compared intraoperative anterior, internal rotational, and external rotational stabilities at 0°, 30°, 60°, and 90° of knee flexion using a navigation system after reconstruction. The low femoral tunnel group showed significantly better intraoperative internal rotational stability at 0° and 30° of flexion than the high tunnel group; however, no significant intergroup differences were found for anterior and external rotational stabilities at any flexion angle. These findings suggested that the low femoral tunnel group showed better internal rotational stability at time zero condition during ACL reconstruction than the high femoral tunnel group, but anterior and external rotational stabilities were similar. However, to determine whether these results may affect clinical results, further studies based on more accurate measurement of rotational stability in clinical settings are needed.
Toe-Touch Weight Bearing: Myth or Reality?
Authors: Rubin Guy , Monder Oded , Zohar Rinat , Oster Ann , Konra Ofra , Rozen Nimrod
Published: October 2010

Toe-touch weight bearing and partial weight bearing are commonly prescribed orders. The purpose of this study is to evaluate the validity of toe-touch weight bearing and partial weight bearing regimens.

Twenty-five orthopedic surgeons participated in the study. They were asked to answer a questionnaire regarding toe-touch weight bearing and partial weight bearing definitions, and were asked to bear weight partially according to the accepted definitions of each order. Weight bearing on the affected limb was measured by the SmartStep System (Andante Medical Devices, Ltd, Omer, Israel).

There was a 40% success rate for toe-touch weight bearing as measured by kilograms and 58% as measured by percentage of body weight. There was a 22% success rate for partial weight bearing as measured by kilograms and 50% success rate as measured by percentage of body weight. For toe-touch weight bearing as measured by kilograms, 52% exerted a mean 15.9 kg more than the maximum. For partial weight bearing as measured by kilograms, 64% exerted too much weight with an average of 14.2 kg more than the maximum. There was a significantly higher success rate for the percentage of body weight order than the kilogram order. The partial weight bearing order with the percent body weight order had a lower mean deviation from desired performance. This study and others demonstrate the need for standardization of weight bearing orders.
Open Reduction Internal Fixation of Displaced Sacral Fractures: Technique and Results
Authors: Hsu Joseph R. , Bear Russell R. , Dickson Kyle F.
Published: October 2010

Pelvic ring disruption with an associated sacral fracture is typically a result of high-energy injury. Due to significant local soft tissue trauma and the complex neurovascular anatomy in the region, exposure and reduction of sacral fractures has proven to be difficult, hazardous, and fraught with complications. We describe a modified reduction technique to address displacement in sacral fractures to show that it can be safe and effective through evaluation of radiographic, clinical, and functional outcomes. We retrospectively reviewed the radiographic and clinical results of consecutive patients treated at a single institution by the senior surgeon (K.F.D.) with open reduction for displaced sacral fractures. Radiographic follow-up was available on all patients. Complete clinical follow-up was available on 19 of 20 patients. The average duration of follow-up was 3.7 years. All fractures united with no additional surgery. There were no infections or additional neurologic deficits or vascular injuries. There was 1 asymptomatic hardware failure 2 years postoperatively with no further displacement. Average preoperative displacement on the anteroposterior (AP) radiograph was 14.72 mm with a long-term follow-up displacement of 3.25 mm. Iowa Pelvic Score questionnaires demonstrated an average score of 92.2. Eighty-nine percent of patients returned to full time work or their previous activity level. The technique of open reduction and fixation of displaced sacral fractures described in this review is safe and effective with a low complication rate and clinical results comparable to or exceeding that of previously published series.
Acute Limb Ischemia Following Closed Reduction of a Hip Arthroplasty Dislocation
Authors: Marsh Jonathan P. , Turgeon Thomas , Guzman Randolph
Published: October 2010

Hip dislocation is a well-described complication of total hip arthroplasty (THA) and dislocation rates are substantially higher following revision hip arthroplasty. Vascular complications following closed reduction of hip dislocations are exceedingly rare, but a high index of suspicion is essential for patients with underlying vascular abnormalities. Popliteal artery aneurysms are the most common peripheral arterial aneurysms with a prevalence of 1% and they should be suspected in patients with prominent popliteal pulses. This article presents a case of an 84-year-old man with a revision total THA who sustained a posterior hip dislocation. The hip was reduced under conscious sedation using the Bigelow technique. The leg was distally neurovascularly intact based on the clinical exam immediately before and after the reduction. Over the next few hours, the foot became progressively ischemic and an urgent computed tomography angiogram revealed bilateral popliteal artery aneurysms with acute thrombosis of the aneurysm on the affected limb. The patient underwent emergent femoral popliteal bypass using a Dacron supported interpositional graft. The majority of the foot was salvaged but the toes eventually became necrotic. Direct compression of the aneurysm during reduction of the hip dislocation in conjunction with transiently decreased blood pressure from conscious sedation likely resulted in a low flow state within the artery leading to thrombosis of the aneurysm. To our knowledge, this is the first reported case of such an event. This case emphasizes the need for a high index of suspicion for vascular injuries following manipulation of limbs with underlying arterial aneurysms. Reduction maneuvers for hip dislocations should be modified to minimize compression of the popliteal fossa in limbs with vascular abnormalities. Serial postreduction neurovascular exams are essential for identification and prompt management of vascular complications.
Recurrent Hemarthrosis in a Hemophilic Patient After Revision Total Knee Arthroplasty
Authors: Park Justin J. , Slover James D. , Stuchin Steven A.
Published: October 2010

Recurrent hemarthrosis following a revision total knee arthroplasty is a rare complication. The likelihood of encountering bleeding complications in patients with hemophilia C following major surgery is unpredictable. Although the use of postoperative chemotherapeutic agents to prevent deep venous thrombosis (DVT) is considered the standard of care for most patients, its use in the hemophiliac population is unknown. This case describes a woman with Hemophilia C who presented with recurrent hemarthrosis 9 days after her revision total knee arthroplasty. Initial treatment efforts were directed towards treating the patient’s underlying coagulopathy. Repeated transfusions of fresh frozen plasma and desmopressin were given in an attempt to achieve hemostasis. However the hemarthrosis did not resolve and 36 days postoperatively, a pseudoaneurysm of the left superior geniculate artery was found by angiography and percutaneously embolized. This article presents the first case, to our knowledge, of recurrent hemarthrosis in a hemophiliac patient after revision total knee arthroplasty. It further highlights the importance of considering all possible causes of postoperative bleeding to make a timely diagnosis in the face of a confounding clinical picture.
Septic Knee-Induced Deep Venous Thrombosis in a Young Adult
Authors: Backes Jeffrey , Taylor Benjamin C. , Clayton Matthew D.
Published: October 2010

This article describes a case of a 26-year-old man presenting with left knee pain of 1 week’s duration, fever, and acute onset of shortness of breath the day of admission. An arthrocentesis of the knee joint was grossly positive for methicillin-resistant
Staphylococcus aureus
. A left lower extremity venous duplex showed thrombosis of the superficial femoral, popliteal, posterior tibial, peroneal, and gastrocnemius veins. Pulmonary computed tomography–angiography was positive for acute pulmonary emboli. Initial management consisted of anticoagulation, intravenous antibiotics, and 2 arthroscopic irrigation and debridement procedures. After a normal transesophageal echocardiogram, a diagnosis of septic knee-induced deep venous thrombosis (DVT) of the left lower leg with subsequent septic pulmonary emboli was established.

The patient was discharged to a long-term care facility for a 6-week monitored course of intravenous antibiotics. His DVT and pulmonary emboli were managed successfully with oral warfarin. Two months after his initial presentation, the patient returned with acute worsening knee pain. A knee arthrocentesis was unremarkable; however, radiographic imaging revealed fulminant osteomyelitis of the distal femur. He has since undergone open arthrotomy with excisional irrigation and debridement and is on a chronic oral antibiotic regimen.

Sparse pediatric literature has shown an association between musculoskeletal sepsis and thrombosis. Only 1 case of septic knee-induced DVT exists in the adult literature, and it was not associated with pulmonary emboli. Our case provides evidence that DVT must be considered by the treating physician as a possible and devastating complication of septic arthritis.
Extracorporeal Shock Wave Therapy for Calcific Tendinitis at Unusual Sites Around the Hip
Authors: Oh Kwang-Jun , Yoon Jung-Ro , Shin David Sung-Joon , Yang Jae-Hyuk
Published: October 2010

Extracorporeal shock wave therapy has been considered to be an effective treatment for various pathogenic orthopedic conditions. However, it is not generally recognized in treatment for calcific tendinitis around the hip region. This article presents 2 cases of calcific tendinitis at the hip, located in the pectineus muscle and the rectus femoris muscle, where successful treatment was achieved using extracorporeal shock wave therapy.

In 1 case, a 60-year-old woman presented with pain in her right thigh of 1 month’s duration that had become severe in intensity for 1 week. Physical examination revealed marked localized tenderness over the posterolateral aspect of the right thigh when positioned in flexion, abduction, and external rotation. Anteroposterior and frog-leg lateral radiographs revealed nodular-shaped calcium deposits at the posterolateral aspect of the proximal thigh. T1- and T2-weighted magnetic resonance imaging of the hip joint revealed a 2.7×1.3-cm, low-signal density area near the femoral insertion of pectineus and gluteus maximus muscle with inflammatory infiltration in the surrounding soft tissue. Treatment was started in the form of extracorporeal shock wave therapy, doses of which were administered in 3 sessions with an interval of 7 days. Radiographs of the affected thigh taken 4 weeks after therapy showed disintegration of the calcium deposits.
Bilateral Simultaneous Femoral Diaphyseal Fractures in a Patient with Long-Term Ibandronate Use
Authors: Patel Vishal C. , Lazzarini Adam M.
Published: October 2010

Bisphosphonates are the most common medication used to treat patients with documented osteoporosis. Recently, reports have associated long-term bisphosphonate use with low-energy femur fractures. While no definitive mechanism has been associated, bisphosphonate use has been strongly implicated. This article presents the case of a 65-year-old woman with a 2-year history of ibandronate use presenting with simultaneous low-energy femoral shaft fractures. The patient reported prodromal bilateral thigh pain and was seen by a spine surgeon.

A review of the literature implicates long-term ibandronate use in low-energy femur fractures. With most of the basic science studies demonstrating suppressed bone turnover after 5 years of treatment with alendronate, the significance of the present case also lies in the relatively short duration of time the patient was on ibandronate before suffering the bilateral femoral shaft fractures. Possible pathophysiology for the fractures includes suppressed bone turnover that may allow microcracks to propagate in cortical bone, which can weaken the bone and possibly predispose it to fractures. Patients who have been on bisphosphonates long term should be questioned about thigh pain and have radiographs of their femurs obtained if pain exists. Furthermore, if a patient presents with a single subtrochanteric or diaphyseal low-energy femur fracture after long-term bisphosphonate use, a radiograph of the contralateral femur should be obtained to assess for a cortical stress reaction.
Preparing Underemployed Latino U.S. Nurses Through the Mexico NCLEX-RN Success Program
Authors: Lujan Josefina , Little Kermit
Published: October 2010

The critical nursing shortage in U.S. communities along the United States-Mexico border is compounded by the need for nurses who are linguistically and culturally concordant with the growing number of Latinos in these communities. The innovative 16-week Mexico NCLEX-RN Success Program responds to this need by helping underemployed Latino nurses, who were educated in Mexico and live in the United States, adapt linguistically and culturally to multiple-choice testing. Ten of the program students have taken the NCLEX-RN with a 50% pass rate, which is twice as high as the internationally educated candidate passing average. This demonstrates potential for the program to build the human capacity of U.S. communities along the United States-Mexico border by infusing linguistically and culturally concordant nurses into the workforce and materializing the dream of underemployed Latino nurses to implement their hard-earned and urgently needed nursing skills. Lessons learned from the program are discussed.