Imaging of a circumsolar dust ring near the orbit of Venus

The gravitational interaction of dust in the zodiacal cloud with individual planets is expected to give rise to ringlike features: Such a circumsolar ring has been observed associated with Earth, but such resonance rings have not been confirmed to exist for other planets. Here, we report on sensitive photometric observations, based on imaging from the STEREO mission, that confirm the existence of a dust ring at the orbit of Venus. The maximum overdensity of dust in this ring, compared to the zodiacal cloud, is ~10%. The radial density profile of this ring differs from the model used to describe Earth's ring in that it has two distinct steplike components, with one step being interior and the other exterior to the orbit of Venus.

Radiographic joint space width is correlated with 4-year clinical outcomes in patients with knee osteoarthritis: data from the osteoarthritis initiative

OBJECTIVE

To evaluate if quantitative joint space width (JSW) measurements from radiographs correlate with 4-year Knee injury and Osteoarthritis Outcome Scores (KOOS) and clinical performance measures.

METHOD

The study group consisted of 942 patients with symptomatic knee osteoarthritis (OA). 4-year outcomes for six measures (KOOS Pain, Symptom, Quality of Life, and Function scores, 20-m walk pace, and chair stand time) were used to create six multiple linear regression models. Primary predictors were baseline minimum JSW and 4-year change in JSW measured from fixed flexion radiographs. Age, gender, body mass index (BMI), race, knee alignment, and baseline measures of the outcomes of interest were covariates.

RESULTS

Lower baseline minimum JSW and a greater decrease in 4-year JSW significantly correlated with worse 4-year KOOS Pain, Symptom, and Quality of Life. With all other factors constant, a 4.1, 4.8, and 5.6 mm lower baseline JSW correlated with a clinically significant eight-point drop in 4-year KOOS Pain, Symptom, and Quality of Life scores respectively. Additionally, a 3.5, 3.1, and 4.0 mm loss of JSW over 4 years correlated with a clinically significant eight-point drop in 4-year KOOS Pain, Symptom, and Quality of Life scores respectively.

CONCLUSIONS

Our results indicate quantitative radiographic JSW measurements correlate with 4-year clinical outcomes. Since patients with narrower JSW at the onset of study had lower KOOS scores at 4 years even after controlling for 4-year change in JSW and baseline KOOS scores, clinical outcomes in knee OA may be predetermined once the disease process begins. These findings suggest early treatment with disease modifying therapies may be necessary to influence outcomes.

Variability in ACL tunnel placement: observational clinical study of surgeon ACL tunnel variability

BACKGROUND

Multicenter and multisurgeon cohort studies on anterior cruciate ligament (ACL) reconstruction are becoming more common. Minimal information exists on intersurgeon and intrasurgeon variability in ACL tunnel placement. Purpose/

HYPOTHESIS

The purpose of this study was to analyze intersurgeon and intrasurgeon variability in ACL tunnel placement in a series of The Multicenter Orthopaedic Outcomes Network (MOON) ACL reconstruction patients and in a clinical cohort of ACL reconstruction patients. The hypothesis was that there would be minimal variability between surgeons in ACL tunnel placement.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Seventy-eight patients who underwent ACL reconstruction by 8 surgeons had postoperative imaging with computed tomography, and ACL tunnel location and angulation were analyzed using 3-dimensional surface processing and measurement. Intersurgeon and intrasurgeon variability in ACL tunnel placement was analyzed.

RESULTS

For intersurgeon variability, the range in mean ACL femoral tunnel depth between surgeons was 22%. For femoral tunnel height, there was a 19% range. Tibial tunnel location from anterior to posterior on the plateau had a 16% range in mean results. There was only a small range of 4% for mean tibial tunnel location from the medial to lateral dimension. For intrasurgeon variability, femoral tunnel depth demonstrated the largest ranges, and tibial tunnel location from medial to lateral on the plateau demonstrated the least variability. Overall, surgeons were relatively consistent within their own cases. Using applied measurement criteria, 85% of femoral tunnels and 90% of tibial tunnels fell within applied literature-based guidelines. Ninety-one percent of the axes of the femoral tunnels fell within the boundaries of the femoral footprint.

CONCLUSION

The data demonstrate that surgeons performing ACL reconstructions are relatively consistent between each other. There is, however, variability of average tunnel placement up to 22% of mean condylar depth, likely reflecting the difference in individual surgeons' preferred tunnel locations. Individual surgeons are relatively consistent in their cases of ACL tunnels.

Surgery versus physical therapy for a meniscal tear and osteoarthritis

BACKGROUND

Whether arthroscopic partial meniscectomy for symptomatic patients with a meniscal tear and knee osteoarthritis results in better functional outcomes than nonoperative therapy is uncertain.

METHODS

We conducted a multicenter, randomized, controlled trial involving symptomatic patients 45 years of age or older with a meniscal tear and evidence of mild-to-moderate osteoarthritis on imaging. We randomly assigned 351 patients to surgery and postoperative physical therapy or to a standardized physical-therapy regimen (with the option to cross over to surgery at the discretion of the patient and surgeon). The patients were evaluated at 6 and 12 months. The primary outcome was the difference between the groups with respect to the change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical-function score (ranging from 0 to 100, with higher scores indicating more severe symptoms) 6 months after randomization.

RESULTS

In the intention-to-treat analysis, the mean improvement in the WOMAC score after 6 months was 20.9 points (95% confidence interval [CI], 17.9 to 23.9) in the surgical group and 18.5 (95% CI, 15.6 to 21.5) in the physical-therapy group (mean difference, 2.4 points; 95% CI, -1.8 to 6.5). At 6 months, 51 active participants in the study who were assigned to physical therapy alone (30%) had undergone surgery, and 9 patients assigned to surgery (6%) had not undergone surgery. The results at 12 months were similar to those at 6 months. The frequency of adverse events did not differ significantly between the groups.

CONCLUSIONS

In the intention-to-treat analysis, we did not find significant differences between the study groups in functional improvement 6 months after randomization; however, 30% of the patients who were assigned to physical therapy alone underwent surgery within 6 months. (Funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases; METEOR ClinicalTrials.gov number, NCT00597012.).

Theoretical model of the effect of combined glenohumeral bone defects on anterior shoulder instability: a finite element approach

The presence of either a Hill-Sachs or a bony Bankart defect has been indicated as a possible cause of subluxation and anterior shoulder dislocation. Previous studies investigated only the effects of isolated humeral or glenoid defects on glenohumeral instability. We investigated the effects on shoulder stability of both glenoid and humeral defects in the glenohumeral joint. A computer-based finite element approach was used to model the joint. A generic model was developed for cartilage and bone of the glenoid and humerus, using previously published data, and experiments were analyzed using static analysis with displacement control in the anterior-inferior direction. Simulations were run with a 50-N compressive load in the presence of both isolated and combined defects to analyze reaction forces and distance to dislocation. The distance to dislocation for normal joint was 13.6 mm at 90° abduction, which reduced to 9.7, 0, and 0 mm for largest isolated humerus defect, glenoid defect, and certain combined defects, respectively. For combined defects, stability ratio was decreased to 0% from 43%. Our results suggest that in the setting of combined bone defects, stability may be reduced more than what is known for isolated defects alone.

Analysis of baseball-to-helmet impacts in major league baseball

BACKGROUND

In Major League Baseball (MLB), helmet hit-by-pitch (H-HBP) incidents are a leading cause of concussion. However, not all H-HBPs result in diagnosed concussion.

PURPOSE

This study was designed to (1) quantify batter concussion risk as a function of H-HBP pitch velocity, time duration batter spent on the ground post-H-HBP, first responder assessment time duration, and number of days missed post-H-HBP and (2) estimate H-HBP impact locations on the helmet with respect to current National Operating Committee on Standards for Athletic Equipment (NOCSAE) helmet test standards and correlate impact locations with concussion diagnosis.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

A retrospective case-control study of 18 MLB players with H-HBP incidents in the 2009 and 2010 seasons was undertaken. A database was compiled via quantitative and qualitative analysis using video coverage obtained from MLB. Quantitative factors included batter concussion diagnosis, pitch velocity, number of days missed post-H-HBP, time duration batter spent on the ground post-H-HBP, and first responder assessment time duration. The H-HBP impact location was among several qualitative factors developed via video analysis of each H-HBP from 4 raters.

RESULTS

In our study, 9 players (50%) were diagnosed with concussion. Concussion diagnoses were more frequent for posterior versus anterior impacts. The majority of H-HBP impact locations were different from those in the current NOCSAE standard tests. First responders took an average of approximately 65 seconds (time to reach batter plus assessment time) to decide on batter removal/return to play. The 25% logistic regression concussion risk threshold for pitch velocity and days missed was 86.2 mph and 1.3 days, respectively. The number of days missed after H-HBP showed a significant correlation (P = .02) among concussed and nonconcussed batters.

CONCLUSION

In professional baseball H-HBP incidents, first responders should (1) be aware of pitch velocity in excess of 86 mph and (2) be provided ample time when assessing batters' removal/return to play.

CLINICAL RELEVANCE

First responders should not rely solely on visual indicators such as batter reaction, holding head, or amount of time spent on the ground after H-HBP when assessing batters for concussion. Batting helmets in the MLB should maximize protection and mitigate impact dosage for H-HBP impact locations and velocity in addition to NOCSAE standard test locations and velocities.

Arthroscopic agreement among surgeons on anterior cruciate ligament tunnel placement

BACKGROUND

Little is known about surgeon agreement and accuracy using arthroscopic evaluation of anterior cruciate ligament (ACL) tunnel positioning.

PURPOSE

To investigate agreement on ACL tunnel position evaluated arthroscopically between operating surgeons and reviewing surgeons. We hypothesized that operating and evaluating surgeons would characterize tunnel positions significantly differently.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twelve surgeons drilled ACL tunnels on 72 cadaveric knees using transtibial (TT), medial portal (MP), or 2-incision (TI) techniques and then completed a detailed assessment form on tunnel positioning. Then, 3 independent blinded surgeon reviewers each arthroscopically evaluated tunnel position and completed the assessment form. Statistical comparisons of tunnel position evaluation between operating and reviewing surgeons were completed. Three-dimensional (3D) computed tomography (CT) scans were performed and compared with arthroscopic assessments. Arthroscopic assessments were compared with CT tunnel location criteria.

RESULTS

Operating surgeons were significantly more likely to evaluate femoral tunnel position (92.6% vs 69.2%; P = .0054) and femoral back wall thickness as "ideal" compared with reviewing surgeons. Tunnels were judged ideal by reviewing surgeons more often when the TI technique was used compared with the MP and TT techniques. Operating surgeons were more likely to evaluate tibial tunnel position as ideal (95.5% vs 57.1%; P < .0001) and "acceptable" compared with reviewers. The ACL tunnels drilled using the TT technique were least likely to be judged as ideal on the tibia and the femur. Agreement among surgeons and observers was poor for all parameters (κ = -0.0053 to 0.2457). By 3D CT criteria, 88% of femoral tunnels and 78% of tibial tunnels were placed within applied criteria.

CONCLUSION

Operating surgeons are more likely to judge their tunnels favorably than observers. However, independent surgeon reviewers appear to be more critical than results of 3D CT imaging measures. When subjectively evaluated arthroscopically, the TT technique yields more subjectively poorly positioned tunnels than the TI and MP techniques. Surgeons do not agree on the ideal placement for single-bundle ACL tunnels.

CLINICAL RELEVANCE

This study demonstrates that surgeons do not currently uniformly agree on ideal single-bundle tunnel placement and that the TT technique may yield more poorly placed tunnels.

Quantifying glenoid bone loss in anterior shoulder instability: reliability and accuracy of 2-dimensional and 3-dimensional computed tomography measurement techniques

BACKGROUND

Glenoid support is critical for stability of the glenohumeral joint. An accepted noninvasive method of quantifying glenoid bone loss does not exist.

PURPOSE

To perform independent evaluations of the reliability and accuracy of standard 2-dimensional (2-D) and 3-dimensional (3-D) computed tomography (CT) measurements of glenoid bone deficiency.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Two sawbone models were used; one served as a model for 2 anterior glenoid defects and the other for 2 anteroinferior defects. For each scapular model, predefect and defect data were collected for a total of 6 data sets. Each sample underwent 3-D laser scanning followed by CT scanning. Six physicians measured linear indicators of bone loss (defect length and width-to-length ratio) on both 2-D and 3-D CT and quantified bone loss using the glenoid index method on 2-D CT and using the glenoid index, ratio, and Pico methods on 3-D CT. The intraclass correlation coefficient (ICC) was used to assess agreement, and percentage error was used to compare radiographic and true measurements.

RESULTS

With use of 2-D CT, the glenoid index and defect length measurements had the least percentage error (-4.13% and 7.68%, respectively); agreement was very good (ICC, .81) for defect length only. With use of 3-D CT, defect length (0.29%) and the Pico(1) method (4.93%) had the least percentage error. Agreement was very good for all linear indicators of bone loss (range, .85-.90) and for the ratio linear and Pico surface area methods used to quantify bone loss (range, .84-.98). Overall, 3-D CT results demonstrated better agreement and accuracy compared to 2-D CT.

CONCLUSION

None of the methods assessed in this study using 2-D CT was found to be valid, and therefore, 2-D CT is not recommended for these methods. However, the length of glenoid defects can be reliably and accurately measured on 3-D CT. The Pico and ratio techniques are most reliable; however, the Pico(1) method accurately quantifies glenoid bone loss in both the anterior and anteroinferior locations. Future work is required to implement valid imaging techniques of glenoid bone loss into clinical practice.

CLINICAL RELEVANCE

This is one of the only studies to date that has investigated both the reliability and accuracy of multiple indicators and quantification methods that evaluate glenoid bone loss in anterior glenohumeral instability. These data are critical to ensure valid methods are used for preoperative assessment and to determine when a glenoid bone augmentation procedure is indicated.

Multi-investigator collaboration in orthopaedic surgery research compared to other medical fields

An increasing emphasis has been placed across health care on evidence-based medicine with higher level studies, such as randomized trials and prospective cohort studies. Historically, clinical research in orthopaedic surgery has been dominated by studies with low patient numbers from a limited number of surgeons. The purpose of this study was to test our hypothesis that orthopaedics has fewer multi-center collaborative studies as compared to other medical disciplines. We chose three leading journals from general medicine, a leading journal from the surgical subspecialties of obstetrics and gynecology, ophthalmology and otolaryngology, and three leading journals from orthopaedic surgery based on highest impact factor. We compared the percentage of collaborative studies and the number of contributing institutions and authors in original research manuscripts published in 2009 between general medical, surgical subspecialty and orthopaedic surgery journals. A significantly higher percentage of manuscripts resulted from multicenter collaborative efforts in the general medical literature (p < 0.000001) and the other surgical subspecialty literature (p < 0.000001) compared to the orthopaedic surgery literature. Manuscripts published in the general medical journals came from more institutions (p < 0.0001) and had significantly more authors (p < 0.000001) than those published in the orthopaedic surgery journals. There is an opportunity to stimulate greater multicenter collaborative research, which correlates with increased patient numbers, a higher level of evidence and more generalizable findings, in the orthopaedic surgery community. These efforts can be supported through increased funding, surgeon participation, and appropriate expansion of authorship for multicenter studies in orthopaedic journals.

Practice patterns for arthroscopy of osteoarthritis of the knee in the United States

BACKGROUND

Knee arthroscopy is one of the most common orthopaedic procedures performed in the United States. The publication of a randomized controlled trial of arthroscopy versus sham surgery by Moseley et al in 2002 showed no efficacy and challenged the role of arthroscopy for the treatment of osteoarthritis.

HYPOTHESIS

(1) Knee arthroscopy for osteoarthritis has decreased after the publication of the study by Moseley et al, (2) arthroscopy as a percentage of orthopaedic cases has decreased, and (3) the average age of patients undergoing arthroscopy has decreased.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

The authors examined the American Board of Orthopaedic Surgery (ABOS) database that includes 6-month case logs for each examinee sitting for the Part II board examination for 1999 to 2009. Knee arthroscopy cases were identified by CPT (Current Procedural Terminology) code and knee osteoarthritis diagnosis was defined by ICD-9 (International Classification of Diseases, 9th Revision) code. Piecewise linear regression was used to evaluate knee arthroscopy before and after the publication of the Moseley et al article in 2002.

RESULTS

The number of knee arthroscopy cases for patients with osteoarthritis had greatly decreased by 2009 after peaking in 2001 (1621 vs 966 total cases, 2.36 vs 1.40 cases per surgeon). Cases classified as chondroplasty also decreased from 10.0% to 5.8% of knee arthroscopies (P < .0001). In addition, the total number of knee arthroscopy cases per surgeon decreased from a high of 11.9 in 2003 to a low of 8.6 in 2009. As expected, knee arthroscopy as a percentage of total orthopaedic cases decreased from a high of 9.9% in 2003 to 6.6% in 2009 (P < .0001).

CONCLUSION

Knee arthroscopy for patients with osteoarthritis among orthopaedic surgeons during their ABOS examination case collection period has decreased after the publication of a highly publicized article demonstrating a lack of efficacy of this procedure. Further study is needed to determine if this change occurred in the orthopaedic community at large or if practice patterns only changed for surgeons during their board collection periods.

CLINICAL RELEVANCE

Randomized controlled trials can be effective in changing orthopaedic surgeon practice.

Cost-effectiveness of ultrasound use by on-call registrars in an acute gynaecology setting

Ultrasound, and in particular transvaginal sonography (TVS), plays an important role in the management of women with acute gynaecology conditions. This study compared the cost-effectiveness of two models of out-of-hours care for women in an acute gynaecology setting. In the ultrasound-based model, the on-call registrar with ultrasound experience managed such patients after performing pelvic ultrasound as a part of the initial assessment. On the other hand, in the traditional model of care the on-call registrar managed the patients without the use of ultrasound. The conclusion is that the use of ultrasound by the on-call registrars has significant cost implications through reduced hospital admissions. It leads to improved outcomes of such patients through timely diagnosis and treatment.

Accuracy of measurement of Hill-Sachs lesions with computed tomography

BACKGROUND

Bone defects play a role in recurrent instability. There is no universal method to quantify humeral head defects. The purpose of this study is to assess the accuracy of 2-dimensional computed tomography (CT) scan measurements of Hill-Sachs lesions.

MATERIALS AND METHODS

Six Hill-Sachs defects were created in anatomically shaped bone substitutes. The samples were scanned with a 3-dimensional laser scanner. Maximum width and depth were measured and used as the true measurement. The samples underwent routine CT scanning, and 5 physicians measured maximum width and depth on each plane independently. The intraclass correlation coefficient (ICC) was used to assess agreement. Percent error and paired t test were used for statistical analysis (P < .05 denoted significance).

RESULTS

The ICC between observers was 0.879 (95% confidence interval, 0.780-0.946) and 0.721 (95% confidence interval, 0.543-0.865) for the depth and width measurement, respectively. The ICC was good between individual observers and the true measurement (range, 0.765-0.956). Individual observers were more accurate in depth rather than width measurements. The mean overall percent error of the depth and width measurements for the 6 defects was calculated: coronal, 19.2% ± 13.6%; sagittal, 11.8% ± 8.2%; and axial, 13.6% ± 8.4%.

CONCLUSIONS

The depth of Hill-Sachs lesions can be reliably assessed using CT scan. Observers consistently underestimated width in all imaging planes. Overall, sagittal- and axial-plane measurements are more accurate for evaluation of these defects than the coronal plane. Future studies using 3-dimensional CT may be helpful to further quantitatively assess the size of the Hill-Sachs lesion, including width and volume.

Revision ACL reconstruction outcomes: MOON cohort

Many clinicians believe that the results of revision anterior cruciate ligament (ACL) reconstruction compare unfavorably with primary ACL reconstruction. However, few prospective studies have evaluated revision ACL reconstruction using validated patient-based metrics. This study was performed to evaluate and compare the results of revision ACL reconstruction and primary ACL reconstruction. The Multicenter Orthopaedic Outcomes Network consortium is an NIH-funded, hypothesis-driven, multicenter prospective cohort study of patients undergoing ACL reconstruction. All patients preoperatively complete a series of validated patient-oriented questionnaires. At scheduled 2-year follow-up all patients are given the same series of questionnaires to complete. The study evaluated the results of 2-year follow-up of revision ACL reconstruction performed in 2001. Parameters evaluated included Marx activity level, Knee Injury and Osteoarthritis Outcome Score (KOOS), and International Knee Documentation Committee (IKDC) scores. For this study 446 subjects met inclusion criteria; 2-year follow-up was obtained on 393 (88%). The study group consisted of 55% males with median age of 22 years. There were 33 revision ACL reconstruction cases, for which follow-up was available for 29 (88%). Median baseline Marx (interquartile range) was 12 (8 to 16) and 12 (6 to 16) for the primary ACL reconstruction and revision ACL reconstruction groups, respectively (p= 0.81). At 2 years, median Marx was 9 (4 to 13) and 5 (0 to 10) for the primary ACL reconstruction and revision ACL reconstruction groups, respectively (p= 0.03). Median 2-year IKDC was 75.9 (revision) versus 83.9 (primary) (p=0.003). Median KOOS subscale Knee Related Quality of Life (KRQOL) at 2 years was 62.5 (revision) versus 75 (primary) (p < 0.001), subscale Sports and Recreation was 75 (revision) and 85 (primary) (p = 0.005), subscale Pain was 83.3 (revision) and 91.7 (primary) (p= 0.002). Marx activity score declined at 2-year follow-up in revision ACL reconstruction compared with primary ACL reconstruction. IKDC and KRQOL were significantly decreased in revision ACL reconstruction compared with primary ACL reconstruction at 2-year followup. Revision ACL reconstruction resulted in a significantly worse outcome as measured by these patient-based measures at 2 years.

Hop tests correlate with IKDC and KOOS at minimum of 2 years after primary ACL reconstruction

PURPOSE

The hypothesis of this study was that single-legged horizontal hop test ratios would correlate with IKDC, KOOS, and Marx activity level scores in patients 2 years after primary ACL reconstruction.

METHODS

Individual patient-reported outcome tools and hop test ratios on 69 ACL reconstructed patients were compared using correlations and multivariable modeling. Correlations between specific questions on the IKDC and KOOS concerning the ability to jump and hop ratios were also performed.

RESULTS

The triple-hop ratio was moderately but significantly correlated with the IKDC, KOOS Sports and Recreation subscale, and the KOOS Knee Related Quality of Life subscale, as well as with the specific questions related to jumping. Similar but weaker relationship patterns were found for the single-hop ratio and timed hop. No significant correlations were found for the Marx activity level or crossover-hop ratio. Multivariable modeling showed almost no significant additional contribution to predictability of the IKDC or KOOS subscores by gender, BMI, or the number of faults on either leg.

CONCLUSIONS

The triple-hop test is most significantly correlated with patient-reported outcome scores. Multivariable modeling indicates that less than a quarter of the variability in outcome scores can be explained by hop test results. This indicates that neither test can serve as a direct proxy for the other; however, assessment of patient physical function by either direct report using validated outcome tools or by the hop test will provide relatively comparable data.

Plasma brain-derived neurotrophic factor levels are associated with clinical severity in school age children with asthma

BACKGROUND

Asthma is characterized by chronic inflammation of the airways with significant changes in leucocyte trafficking, cellular activation and tissue remodelling. Brain-derived neurotrophic factor (BDNF) has been involved with asthma and allergic diseases but its role as a severity marker in paediatric asthma has not been clinically assessed.

OBJECTIVES

To evaluate plasma BDNF and inflammatory markers in order to address their relationships with disease severity in children (6-15 years) with controlled persistent asthma.

METHODS

Children with persistent asthma were selected and lung function and skin prick tests were performed in all patients. Plasma BDNF levels and various inflammatory markers (CCL3, CCL11, CCL22, CCL24, CXCL8, CXCL9, CXCL10, soluble TNF receptors) were assessed by ELISAs.

RESULTS

Subjects with moderate and severe asthma had higher BDNF levels than mild asthma and controls (P<0.001). The chemokines studied and soluble TNF receptors did not differ between the studied groups.

CONCLUSION AND CLINICAL RELEVANCE

Our results indicate BDNF as a potential biomarker for clinical severity in children with asthma.

Which preoperative factors, including bone bruise, are associated with knee pain/symptoms at index anterior cruciate ligament reconstruction (ACLR)? A Multicenter Orthopaedic Outcomes Network (MOON) ACLR Cohort Study

BACKGROUND

Increased knee pain at the time of anterior cruciate ligament reconstruction may potentially predict more difficult rehabilitation, prolonged recovery, and/or be predictive of increased knee pain at 2 years.

HYPOTHESIS

A bone bruise and/or other preoperative factors are associated with more knee pain/symptoms at the time of index anterior cruciate ligament reconstruction, and the presence of a bone bruise would be associated with specific demographic and injury-related factors.

STUDY DESIGN

Cohort study (prevalence); Level of evidence, 2.

METHODS

In 2007, the Multicenter Orthopaedic Outcomes Network (MOON) database began to prospectively collect surgeon-reported magnetic resonance imaging bone bruise status. A multivariable analysis was performed to (1) determine if a bone bruise, among other preoperative factors, is associated with more knee symptoms/pain and (2) examine the association of factors related to bone bruise. To evaluate the association of a bone bruise with knee pain/symptoms, linear multiple regression models were fit using the continuous scores of the Knee injury and Osteoarthritis Outcome Score (KOOS) symptoms and pain subscales and the Short Form 36 (SF-36) bodily pain subscale as dependent variables. To examine the association between a bone bruise and risk factors, a logistic regression model was used, in which the dependent variable was the presence or absence of a bone bruise.

RESULTS

Baseline data for 525 patients were used for analysis, and a bone bruise was present in 419 (80%). The cohort comprises 58% male patients, with a median age of 23 years. The median Marx activity level was 13. Factors associated with more pain were higher body mass index (P < .0001), female sex (P = .001), lateral collateral ligament injury (P = .012), and older age (P = .038). Factors associated with more symptoms were a concomitant lateral collateral ligament injury (P = .014), higher body mass index (P < .0001), and female sex (P < .0001). Bone bruise is not associated with symptoms/pain at the time of index anterior cruciate ligament reconstruction. None of the factors included in the SF-36 bodily pain model were found to be significant. After controlling for other baseline factors, the following factors were associated with a bone bruise: younger age (P = .034) and not jumping at the time of injury (P = .006).

CONCLUSION

After anterior cruciate ligament injury, risk factors associated with a bone bruise are younger age and not jumping at the time of injury. Bone bruise is not associated with symptoms/pain at the time of index anterior cruciate ligament reconstruction.

Patient-reported outcome measures for the knee

In the past 20 years, there has been considerable growth in the number of knee instruments and rating scales designed to measure outcomes from the perspective of the patient. Only a few of these instruments have been evaluated for reliability, validity, and responsiveness. The purpose of this systematic review was to examine the psychometric evidence of patient-reported outcome measures for the knee and identify the best scores for specific knee conditions. A literature search was performed to retrieve references relating to the development and evaluation of knee-specific instruments. Twenty-four unique instruments were identified, and most have satisfactory evidence for internal (alpha > or = 0.82) and test-retest reliability (intraclass correlation coefficient > or = 0.80). Face/content validity was typically assessed during the item selection process, and construct validity was evaluated through strict hypothesis testing or correlations with other clinical measures. For many instruments, effect sizes and standardized response means measuring responsiveness were large (> or = 0.80) within disease-specific populations. Based on the psychometric data, recommendations include the Cincinnati Knee Rating System, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Lysholm Knee Score for anterior cruciate ligament (ACL) injuries, the Kujala Anterior Knee Pain Scale for anterior knee pain, the International Knee Documentation Committee (IKDC) Subjective Knee Form, KOOS, and Lysholm Knee Score for focal chondral defects, the Western Ontario Meniscal Evaluation Tool (WOMET) for meniscal injuries, and the KOOS for osteoarthritis (OA). Although the IKDC can be used as a general knee measure, no instrument is currently universally applicable across the spectrum of knee disorders and patient groups. Clinicians and researchers looking to use a patient-based score for measurement of outcomes must consider the specific patient population in which it has been evaluated. Using a diagnostic algorithm that measures the anatomic parts of the knee as separate constructs may solve this dilemma, allowing for measurement of treatment outcomes across patient groups and selection of the optimal clinical intervention.

Method for Delivering a Controlled Impact to Articular Cartilage in the Rabbit Knee

OBJECTIVE

The authors aimed to develop a mechanical model for delivering controlled impact injuries to an articular cartilage surface, with the ability to control peak contact pressure while maintaining a constant rate of loading across all impact levels.

METHODS

A pendulum-style impactor with a direct contact interface was fabricated, based on previously published successful models. This impactor was tested in 2 separate experiments: first with a single analog specimen and next with 15 cadaveric rabbit knee specimens. In both experiments, impacts were performed at 3 pressure levels with multiple repetitions. Peak pressure, rate of pressure application, impulse, and time to peak were evaluated.

RESULTS

There was a significant difference between each of the pressure level groups for both the analog and cadaveric experiments. There was no significant difference between the rates of pressure application for the analog specimen and a statistically significant difference only between the highest and lowest pressure level groups for the cadaveric specimen.

CONCLUSIONS

Previous studies have shown that peak pressure and rate of pressure application are both significant contributors to cartilage injury. Previous models have controlled only peak contact pressure, allowing rate of loading to change as a function of peak contact pressure. This model is the first to control both variables, with a rate of pressure application that is typical of an athletic or traumatic injury in humans. Use of this model will enable researchers to investigate the isolated effects of peak pressure on progressive cartilage injuries.

Effect of humeral head defect size on glenohumeral stability: a cadaveric study of simulated Hill-Sachs defects

BACKGROUND

Hill-Sachs lesions are often present with recurrent shoulder instability and may be a cause of failed Bankart repair.

HYPOTHESIS

Glenohumeral joint stability decreases with increasingly larger humeral head defects.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Humeral head defects, 1/8, 3/8, 5/8, and 7/8 of the humeral head radius, were created in 8 human cadaveric shoulders, simulating Hill-Sachs defects. Testing positions included 45 degrees and 90 degrees of abduction and 40 degrees of internal rotation, neutral, and 40 degrees of external rotation. Testing occurred at each defect size sequentially from smallest to largest for all abduction and rotation combinations. The humeral head was translated at 0.5 mm/s 45 degrees anteroinferiorly to the horizontal glenoid axis until dislocation. Distance to dislocation, defined as humeral head translation until it began to subluxate, was the primary outcome measure.

RESULTS

Significant factors by ANOVA were rotation (P < .001) and defect size (P < .001). There was no difference for the 2 abduction angles. External rotation of 40 degrees significantly reduced distance to dislocation compared with neutral and 40 degrees internal rotation (P < .001). Osteotomies of 5/8 and 7/8 radius significantly decreased distance to dislocation over the intact state (P = .009 and P <.001, respectively). Post hoc analysis determined significant differences for the rotational positions. Decreased distance to dislocation occurred at 5/8 radius osteotomy at 40 degrees external rotation with 90 degrees of abduction (P = .008). For the 7/8 radius osteotomy at 90 degrees abduction, there was a decreased distance to dislocation for neutral and 40 degrees external rotation (P < .001); at 45 degrees abduction, there was a decreased distance to dislocation at 40 degrees external rotation (P <.001). With the humerus internally rotated, there was no significant change in distance to dislocation.

CONCLUSION

Glenohumeral stability decreases at a 5/8 radius defect in external rotation and abduction. At 7/8 radius, there was a further decrease in stability at neutral and external rotation.

CLINICAL RELEVANCE

Defects of 5/8 the humeral head radius may require treatment to decrease the failure rate of shoulder instability repair.

Expectant management of first-trimester miscarriage

Miscarriage is the most common complication of pregnancy, which creates a significant workload for health-care professionals. For decades, surgical evacuation of the uterus has remained the conventional treatment of first-trimester miscarriage. Recently, non surgical treatments have been introduced with increasing popularity. This review explores the evidence in support of expectant management of first-trimester miscarriage. It is safe, effective and well-tolerated by women. It enhances women's choice and control. It generates significant cost savings compared with the traditional surgical management. Accurate diagnosis, counselling, 24/7 telephone advice and follow-up are among the important aspects of expectant management. More studies are needed to develop methods for identifying miscarriages suitable for expectant management.

Neutrophilic airway inflammation is a main feature of induced sputum in nonatopic asthmatic children

BACKGROUND

Asthma phenotypes are well described among children. However, there are few studies comparing airway inflammation in different clinical presentations of pediatric asthma. We tested the hypothesis that nonatopic asthma is associated with a predominant noneosinophilic inflammation in the airways, as assessed by induced sputum. The objective of this study was to evaluate the cytological characteristics of induced sputum (IS) in atopic (AA), nonatopic asthmatics (NAA) and nonatopic nonasthmatic children (NANA).

METHODS

Of 90 selected children, 77 met eligibility criteria for performing IS and were classified as: AA, n = 28, NAA, n = 29 and NANA, n = 19. Subjects answered to a set of ISAAC-based questions and were skin-tested for common aeroallergens. A defined series of exclusion criteria was applied.

RESULTS

Induced sputum was obtained from 54 (70.1%) subjects (21 AA, 20 NAA and 13 NANA). Demographic data and mean FEV(1) were similar in the three groups. The proportion of eosinophils [median, inter quartile range (IQR)] was significantly higher in the sputum of AA [(6.0.)12)] compared with NAAs [0 (2)] and NANAs [0 (1)], P < 0.001. The proportion of children with sputum eosinophilia (eos > 3%) was also significantly higher in AA (71.4%) when compared with NAA (28.6%); none of the NANA had sputum eosinophilia. Nonatopic asthmatic children had significantly higher proportions and absolute number of neutrophils than AA and controls.

CONCLUSIONS

The results suggest that nonatopic children present IS with a cell pattern that is predominantly neutrophilic while eosinophilia is the hallmark of airway inflammation in the majority of atopic wheezing children not treated with inhaled steroids.

Treatment of osteoarthritis of the knee (nonarthroplasty)

The clinical practice guideline was explicitly developed to include only treatments less invasive than knee replacement (ie, arthroplasty). Patients with symptomatic osteoarthritis of the knee are to be encouraged to participate in self-management educational programs and to engage in self-care, as well as to lose weight and engage in exercise and quadriceps strengthening. The guideline recommends taping for short-term relief of pain as well as analgesics and intra-articular corticosteroids, but not glucosamine and/or chondroitin. Patients need not undergo needle lavage or arthroscopy with débridement or lavage. Patients may consider partial meniscectomy or loose body removal or realignment osteotomy, as conditions warrant. Use of a free-floating interpositional device should not be considered for symptomatic unicompartmental osteoarthritis of the knee. Lateral heel wedges should not be prescribed for patients with symptomatic medial compartmental osteoarthritis of the knee. The work group was unable either to recommend or not recommend the use of braces with either valgus- or varus-directing forces for patients with medial unicompartmental osteoarthritis; the use of acupuncture or of hyaluronic acid; or osteotomy of the tibial tubercle for isolated symptomatic patellofemoral osteoarthritis.

The 30 minutes decision-to-delivery interval for ‘urgent’ caesarean sections: An elusive target

The aim of this audit was to evaluate whether the '30 minute decision-to-delivery interval' for 'urgent' caesarean section has shown consistent improvement with repeated audit within this unit. The audit dataset comprised a random sample of all urgent caesarean sections carried out in 2004 classified as 'urgent', i.e. to be completed in 30 min. Nearly one-third of caesarean sections recorded on the delivery suite database as 'urgent' were incorrectly coded. A personal review of case notes was undertaken to ensure accurate data capture. Delivery suite data was analysed by post-hoc modelling of a 'normal' (Gaussian) distribution. The proportion of true 'urgent' caesarean sections completed in 30 min was 50% and some 90% of women were delivered within 40 min. The data were normally distributed, with non-random events, accounted for 25% of the variability. A model for 'urgent' caesarean section, accommodating random and non-random factors closely matched the audit data. We conclude that non-random, institutional, factors reflecting overall delivery suite activity adversely effect the decision-to-delivery interval regardless of the performance of personnel and processes within a delivery suite.

Syndesmotic ankle sprains in athletes

Ankle sprains are among the most common athletic injuries and represent a significant source of persistent pain and disability. Despite the high incidence of ankle sprains in athletes, syndesmosis injuries have historically been underdiagnosed, and assessment in terms of severity and optimal treatment has not been determined. More recently, a heightened awareness in sports medicine has resulted in more frequent diagnoses of syndesmosis injuries. However, there is a low level of evidence and a paucity of literature on this topic compared with lateral ankle sprains. As a result, no clear guidelines are available to help the clinician assess the severity of injury, choose an imaging modality to visualize the injury, make a decision in terms of operative versus nonoperative treatment, or decide when the athlete may return to play. Increased knowledge and understanding of these injuries by clinicians and researchers are essential to improve the prevention, diagnosis, and treatment of this significant condition. This review will discuss the anatomy, mechanism of injury, diagnosis, and treatment of syndesmosis sprains of the ankle while identifying controversies in management and topics for future research.

TNF-a and IL-10 levels in tracheobronchial lavage of ventilated preterm infants and subsequent lung function

The role of airway inflammation in ventilated preterm newborns and the risk factors associated with the development of chronic lung disease are not well understood. Our objective was to analyze the association of the airway inflammatory response in ventilated preterm infants by serial measurements of TNF-alpha and IL-10 in tracheobronchial lavage (TBL) with perinatal factors and lung function measured early in life. A series of TBL samples were collected from ventilated preterm infants (less than 32 weeks of gestational age) and concentrations of TNF-alpha and IL-10 were measured by ELISA. Pulmonary function tests were performed after discharge by the raised volume rapid compression technique. Twenty-five subjects were recruited and 70 TBL samples were obtained. There was a significant positive association between TNF-alpha and IL-10 levels and length of time between the rupture of the amniotic membranes and delivery (r = 0.65, P = 0.002, and r = 0.57, P < 0.001, respectively). Lung function was measured between 1 and 22 weeks of corrected age in 10 patients. Multivariable analysis with adjustment for differences in lung volume showed a significant negative association between TNF-alpha levels and forced expiratory flow (FEF(50); r = -0.6; P = 0.04), FEF(75) (r = -0.76; P = 0.02), FEF(85) (r = -0.75; P = 0.03), FEF(25-75) (-0.71; P = 0.02), and FEV(0.5) (r = -0.39; P = 0.03). These data suggest that TNF-alpha levels in the airways during the first days of life were associated with subsequent lung function abnormalities measured weeks or months later.

Nonatopic asthma is associated with helminth infections and bronchiolitis in poor children

Asthma is common in urban centres in Latin America, but atopic asthma may not be the main phenotype among children. Helminth infections are highly prevalent in poor populations, and it was hypothesised that they attenuate allergic asthma, whereas other factors are related to the expression of a nonatopic wheeze/asthma phenotype. A total of 1,982 children from Southern Brazil with a mean+/-sd age of 10.1+/-0.76 yrs completed asthma questionnaires, and 1,011 were evaluated for intestinal parasites and atopy using skin-prick tests (SPTs). Wheeze in the previous 12 months was reported by 25.6%, and 9.3% showed current asthma; 13% were SPT-positive and 19.1% were positive for any helminths. Most children with either wheeze or asthma were SPT-negative; however, severe wheeze was more prevalent among the atopic minority. Helminth infections were inversely associated with positive SPT results. Bronchiolitis before the age of 2 yrs was the major independent risk factor for asthma at age 10 yrs; high-load Ascaris infection, a family history of asthma and positive SPT results were also asthma risk factors. Most asthma and wheeze are of the nonatopic phenotype, suggesting that some helminths may exert an attenuating effect on the expression of the atopic portion of the disease, whereas viral bronchiolitis predisposes more specifically to recurrent airway symptoms.

Acute treatment of inversion ankle sprains: immobilization versus functional treatment

Inversion ankle sprains are one of the most common injuries in sports. Although these injuries are often considered minor, they can lead to persistent disability in athletes. We conducted a systematic review of the literature to evaluate the effect of immobilization versus early functional treatment on time to return to preinjury activity after inversion ankle sprain. Residual subjective instability, recurrent injury, and patient satisfaction were secondary outcomes. A systematic review identified 9 randomized controlled trials. Return to preinjury activity was less with early functional treatment in 4 of 5 studies that evaluated this outcome. Subjective instability was less in 3 of 5 studies. Similarly, reinjury rate was less in 5 of 6 studies. Patient satisfaction was not substantially different in the two studies that evaluated this outcome. Limitations of the identified trials included small sample size, heterogeneity of treatment methods, and lack of standardized outcome measures. However, based on our review the current best evidence suggests a trend favoring early functional treatment over immobilization for the treatment of acute lateral ankle sprains.

Syndesmosis sprains of the ankle: a systematic review

Syndesmosis sprains have received increasing recognition during recent years because of a heightened awareness of the mechanism, symptoms, and signs of injury. Syndesmosis injuries take longer to recover than lateral ankle sprains, and no consensus exists regarding optimal treatment of these injuries. Therefore, we undertook a systematic review of the literature to evaluate the effect of treatment on outcome following syndesmosis injury. We identified six articles that evaluated treatment of syndesmosis injuries. All studies were case series including prospectively collected data of young, active patients with a minimum of 6 months followup and represented the highest level of evidence available. Three specifically addressed patient outcomes at final followup: one indicated 44 percent of patients had acceptable outcomes, and two rated patient outcomes as good to excellent. Time lost from sport ranged from 0 to 137 days, with averages ranging from approximately 10 to 14 days up to 52 days. The studies did not employ consistent diagnosis or grading schemes, did not use uniform treatment protocols, and did not compare treatments. Therefore, this review generates several prospective areas for additional investigation rather than providing strong evidence to support a particular method of treatment.

Navicular Stress Fractures

Since the stress fracture of the tarsal navicular was first described in 1970, awareness of the injury has increased, and navicular stress fractures have represented up to 35% of stress fractures in recent series. However, these injuries remain difficult to diagnose and treat because of their often vague clinical presentation and the poor correlation between radiographic and clinical findings.

Anatomy of the lateral antebrachial cutaneous and superficial radial nerves in the forearm: a cadaveric and clinical study

PURPOSE

To define the anatomy of the lateral antebrachial cutaneous nerve (LACN) and the superficial radial nerve (SRN) in relation to easily identifiable landmarks in the dorsoradial forearm to minimize the risk to both nerves during surgical approaches to the dorsal radius.

METHODS

In this study 37 cadaveric forearms and 20 patients having distal radius external fixation were dissected to identify these nerves in relation to various anatomic landmarks.

RESULTS

Based on these dissections the anatomy was divided into 2 zones that can be identified by easily visible and palpable landmarks. Zone 1 extends from the elbow to the cross-over of the abductor pollicis longus with the extensor carpi radialis brevis and longus. Zone 2 is distal to the cross-over. In zone 1 the 2 nerves can be differentiated through limited incisions based on their depth and anatomic location. Within this zone the SRN is deep to the brachioradialis until 1.8 cm proximal to zone 2 (9 cm proximal to the radial styloid), where it becomes superficial and pierces the fascia of the mobile wad and then remains deep to the subcutaneous fat. In contrast the LACN pierces the fascia between the brachialis and biceps muscles at the level of the elbow. In all specimens the LACN ran parallel to the cephalic vein within the subcutaneous fat. In 31 specimens it ran volar to the vein and in 5 specimens the nerve crossed under the cephalic vein at the elbow and ran dorsal to the vein in the forearm. One specimen had 2 branches with 1 on either side of the vein. Differentiation of these nerves was found to be possible through limited incisions in zone 1 during placement of external fixation pins for distal radius fractures. The LACN always was located in the superficial fat running with the cephalic vein, whereas the SRN was deeper to this nerve either covered by the brachioradialis or closely adherent to it within the investing fascia of the mobile wad. In zone 2 the nerves arborized and ran in the same tissue plane, making differentiation through limited incisions difficult.

CONCLUSIONS

Dividing forearm anatomy into zones aids in understanding the complex 3-dimensional anatomy. Recognition of the consistent location of both the LACN and SRN facilitates surgical exposure. This allows localization through limited incisions during nerve repair and hardware placement, thereby enhancing uncomplicated and favorable outcomes.

Pediatric knee fractures

PURPOSE OF REVIEW

Fractures about the knee are a common occurrence in children, and characteristics of the growing skeleton make children susceptible to specific fractures that do not occur in adults. The purpose of this review is to help the clinician to recognize, understand, and appropriately treat these injuries.

RECENT FINDINGS

Pediatric knee fractures are diagnosed by a comprehensive history and physical examination supplemented with appropriate imaging modalities. Depending on the injury, treatment may include immobilization, arthroscopic treatment, or open reduction and internal fixation.

SUMMARY

A thorough understanding of pediatric knee fractures will enable clinicians to appropriately manage these injuries and provide patients with a rapid return to preinjury activities.

Th-1 and Th-2 cytokine production in infants with virus-associated wheezing

Wheezing associated with respiratory viral infections in infancy is very common and results in high morbidity worldwide. The Th1/Th2 pattern of immune response in these patients remains unclear and previous studies have shown controversial results. The aim of the present study was to compare the type of Th1/Th2 cytokine response between infants with acute bronchiolitis, recurrent wheezing and upper respiratory infections from a developing country. Infants younger than 2 years of age admitted to Hospital São Lucas, Porto Alegre, RS, Brazil, between May and November 2001, with an acute episode of wheezing associated with viral respiratory infection were selected. Subjects with upper respiratory infections from the emergency department were selected for the control group. Interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) levels from nasal aspirates were determined by ELISA from peripheral mononuclear cell cultures. Twenty-nine subjects with acute bronchiolitis, 18 with recurrent wheezing and 15 with upper respiratory infections were enrolled. There were no differences in family history of atopy or parental smoking between groups. Oxygen requirement was similar for the acute bronchiolitis and recurrent wheezing groups. The percentage of positive tests for the cytokines studied and the IFN-gamma/IL-4 ratio was similar for all groups. Comparison of the polarized Th1/Th2 cytokine results for the various groups showed no specific pattern of cytokine production. Infants with wheezing from a developing country do not show any specific predominant pattern of Th1/Th2 cytokine production, suggesting that multiple factors may be involved in the pathogenesis of this illness.

Infection of BALB/c mice with Angiostrongylus costaricensis decreases pulmonary inflammatory response to ovalbumin

SUMMARY The prevalence of asthma in developing countries is lower than in developed countries. Viral, bacterial and parasitic infections may be associated with this discrepancy. The relationship between parasitic infection and asthma prevalence is not clear. Previous controversial data have demonstrated that parasitic infection may either predispose or protect against the development of asthma. The aim of this study is to determine whether infection with Angiostrongylus costaricensis (A. costaricensis) decreases inflammatory lung response to ovalbumin (OVA) in mice. Seven BALB/c mice were infected with A. costaricensis by orogastric gavage (10 larvae/mouse) on day (D) 0. The mice were immunized against OVA by intraperitoneal injection on D 5 and D 12 and received an intranasal OVA challenge (40 micro L) on D 15 and D 17. On D 19 bronchoalveolar lavage (BAL) was performed. Six BALB/c mice (control group) were immunized with OVA using the same protocol, but were not infected with A. costaricensis. Interleukin (IL)-1beta and IL-6 levels were measured in the BAL fluid by using commercial ELISA assays. Total cell counts and differential cell counts were performed in the BAL fluid samples. The group infected with A. costaricensis had lower total cell count in the BAL fluid when compared with the control group (0.11 x 10(6)cells/mL and 0.3 x 10(6)cells/mL, respectively; P = 0.013). BAL fluid IL-1beta levels in the infected group were significantly lower than in the control group (P = 0.008). IL-6 levels in BAL fluid were not different between the groups studied. We conclude that Angiostrongylus costaricensis infection in mice decreases pulmonary inflammatory response to OVA.

The role of meniscal root pathology and radial meniscal tear in medial meniscal extrusion

OBJECTIVE

The purpose of our study was twofold: to better understand the relationship between medial meniscal extrusion (MME) and degenerative joint disease (DJD), and to determine whether a relationship exists between MME and medial meniscal root (MMR) pathology, radial tear and joint effusion.

DESIGN AND PATIENTS

Two hundred and five consecutive MR imaging examinations of the knee were prospectively evaluated, regardless of indication, for the presence and degree of MME, medial compartment marginal osteophytes, medial compartment articular cartilage loss, joint effusion, medial meniscal tear and MMR pathology. MME >or=3 mm was considered abnormal. All studies were performed using a 1.5 T GE Signa MR unit with a quadrature knee coil. The standard protocol included oblique sagittal, coronal and axial imaging.

RESULTS

We found a strong association ( P<0.0001) between >or=3 mm MME and medial joint line osteophytosis (77%), medial compartment articular cartilage loss (69%), MMR pathology (64%) and radial tear (58%) when compared with knees without these findings. Fifty-one percent of cases with a moderate/large joint effusion had <3 mm MME. We found that 20% (31/155) of patients with minimal or no evidence of DJD had >or=3 mm MME. Of this group, 62% (19/31) had either MMR pathology and/or radial tear, 13% (4/31) had joint effusion as their only abnormality and 6% (2/31) had a normal examination (other than the presence of MME). The remaining 19% consisted of three cases of different types of meniscal tear and three cases of small joint effusions but no other detectable pathology.

CONCLUSION

MME >or=3 mm is strongly associated with DJD, MMR pathology and radial tear. A significant number of cases with no or minimal evidence of DJD (20%) had >or=3 mm MME, suggesting that MME precedes, rather than follows, the development of DJD. We also found that joint effusion was not strongly associated with >or=3 mm MME.

The decision-to-delivery interval for emergency caesarean section: is 30 minutes a realistic target?

OBJECTIVE

To evaluate whether a 30-minute decision-to-delivery interval is a realistic target for emergency caesarean section.

DESIGN

An audit of all emergency caesarean sections over five separate periods.

SETTING

A district general hospital.

PARTICIPANTS

Five groups of women (343 women) with an indication for emergency caesarean section.

METHODS

Following an initial survey, a structured time sheet was introduced, followed by four other surveys to complete the audit cycle.

MAIN OUTCOME MEASURE

The proportion of caesarean sections where the decision-to-delivery interval was achieved within 30 minutes. The reasons for delay.

RESULTS

In the first survey of 73 emergency caesarean sections, the time to deliver the infant exceeded 30 minutes in 47 women (64%). The main sources of delay were transferring the women to the operating theatre and starting the anaesthetic. After the introduction of a structured time sheet, there was an improvement with each survey, but the target of 30 minutes was reached in only 71% of caesarean sections in the final survey.

CONCLUSIONS

The introduction of a time sheet can improve the decision-to-delivery interval for emergency caesarean section; however, a universal standard of 100% in 30 minutes is unrealistic.

Yeast Dam1p has a role at the kinetochore in assembly of the mitotic spindle

During mitosis, replicated chromosomes are separated to daughter cells by the microtubule-based mitotic spindle. Chromosomes attach to the mitotic spindle through specialized DNA/protein structures called kinetochores, but the mechanism of attachment is not well understood. We show here that the yeast microtubule-binding protein, Dam1p, associates physically and functionally with kinetochores, suggesting a role in kinetochore attachment to the spindle. An epitope-tagged version of Dam1p colocalizes with the integral kinetochore component Ndc10p/Cbf2p in immunofluorescence analysis of chromosome spreads. In addition, Dam1p is associated preferentially with centromeric DNA as shown by chromatin immunoprecipitation experiments, and this association depends on Ndc10p/Cbf2p. We also demonstrate genetic interactions between DAM1 and CTF19 or SLK19 genes encoding kinetochore proteins. Although the defect caused by the dam1-1 mutation leads to activation of the spindle checkpoint surveillance system and consequent persistence of sister chromatid cohesion, the metaphase arrest spindle abnormally elongates, resulting in virtually complete chromosome missegregation. Execution point experiments indicate that Dam1p has a role in formation of a metaphase spindle and in anaphase spindle elongation. Finally, we have observed that the protein encoded by the dam1-1 allele becomes delocalized at the nonpermissive temperature, correlating with the subsequent onset of the mutant phenotype. Our studies are consistent with a role for Dam1p in attachment of sister chromatids through the kinetochore to the mitotic spindle before chromosome segregation.

An alternative approach to the management dilemma of the mildly dyskaryotic smear based on audit of outcome

We describe a study which takes an alternative approach to the management dilemma of the mildly dyskaryotic cervical smear. Two hundred and fifty women with a smear showing mild dyskaryosis were studied by auditing the clinical outcome as well as the cost. The cost of providing the colposcopy services during the index year was approximately pounds sterling 70000 for an average size district general Hospital. The proportion of women managed by the current guidelines and avoiding colposcopy after a first mildly dyskaryotic smear was only 30%. The majority of patients will eventually have colposcopy despite a policy of cytological surveillance. The alternative approach, to offer colposcopy immediately after the first mildly dyskaryotic smear, would result in a small increase in cost for our unit, equivalent to one extra colposcopy patient per week.

Flow limitation in infants assessed by negative expiratory pressure

Forced expiratory flows by the rapid compression technique are often used to assess airway function in infants; however, it remains unclear as to whether flow limitation (FL) is achieved. Studies in adults have used negative expiratory pressure (NEP) at the airway opening as a noninvasive technique to assess whether FL is achieved. An increase in flow with NEP indicates that FL has not been achieved, whereas no increase in flow with NEP indicates FL has been achieved. In the adult studies, the change in flow was assessed by visual inspection of the flow-volume curve. We evaluated whether NEP could be used to assess FL during forced expiration in infants. In addition, we quantified the change in flow secondary to NEP. We applied -5 cm H(2)O NEP to four infants during forced expiratory maneuvers. The step increase in flow with NEP was always less than 5% at high jacket compression pressures and consistent with FL. For one subject, FL was also confirmed from isovolume pressure flow-curves measured with an esophageal catheter. We conclude that NEP can be used in infants to assess FL during forced expiratory maneuvers by the rapid compression technique.

The use of ultrasound in the diagnosis of injuries of the ulnar collateral ligament of the thumb

We describe the use of a specialist referral clinic and ultrasound assessment for all injuries to the ulnar collateral ligament of the metacarpophalangeal joint of the thumb presenting to an Accident and Emergency (A&E) department. Senior House Officers in the A&E department were able to correctly diagnose only 45% of the ruptures of the ulnar collateral ligament. The overall agreement between specialist clinic examination and ultrasound for injury to the ulnar collateral ligament was 85% (kappa 0.647). When compared with the operative finding ultrasound had a positive predictive value for rupture of 94%. An algorithm is presented for the assessment of injuries to the ulnar collateral ligament in A&E departments.

A novel family of bromodomain genes

The bromodomain is a structural motif characteristic of proteins involved in chromatin-dependent regulation of transcription. Bromodomain proteins have been identified as integral components of chromatin remodeling complexes and frequently possess histone acetyltransferase activity. Their encoding genes have been identified at translocation breakpoints, and at least one, CBP, is a tumor suppressor gene. We have identified a series of novel bromodomain genes by EST database and cDNA library screening. Comparison of sequences for four clones indicated that they represent genes belonging to a novel bromodomain family. Full-length sequences for these genes, which are widely expressed, predict encoded proteins of between 1527 and 1972 amino acids. In addition to a carboxy-terminal bromodomain, an adjacent PHD finger, and a WACZ motif, at least four other conserved novel motifs are present in each protein. The genes contain regions conserved with Drosophila Acf1 and Caenorhabditis elegans ZK783.4. The novel genes, termed BAZ1A, BAZ1B, BAZ2A, and BAZ2B, localize to chromosomes 14q12-q13, 7q11-q21, 12q24.3-qter, and 2q23-q24, respectively. Conservation of multiple domains throughout these genes with Acf1 indicates that they are likely to be components of chromatin remodeling complexes.

Identification and characterization of BPTF, a novel bromodomain transcription factor

The bromodomain is a 110-amino-acid conserved structural region associated with proteins that regulate signal-dependent, nonbasal transcription. The bromodomain can regulate histone acetyl transferase activity and interacts specifically with acetylated lysine residues. A key role for bromodomain proteins in maintaining normal proliferation is indicated by the implication of several bromodomain proteins in cancer, with four of these identified at translocation breakpoints. We searched EST databases for novel bromodomain genes. The sequence from one EST was used to initiate generation of a full-length clone from a testis cDNA library. The completed sequence encodes a predicted protein of 2781 amino acids, which, in addition to the bromodomain, harbors further motifs characteristic of a transcriptional coactivator: two PHD fingers and an extensive glutamine-rich acidic domain. There are several other regions that are conserved with the Caenorhabditis elegans putative protein F26H11, which may be functionally homologous. The novel gene, called BPTF, is expressed in all tissues examined as a 10.5-kb transcript. The protein has extensive identity with the smaller FAC1 protein, suggesting that the two either are derived from the same locus or are synonymous. BPTF has been mapped to 17q23. Functional domains found within BPTF are consistent with a role for this protein in hormonally regulated, chromatin-mediated regulation of transcription.

Yeast Dam1p is required to maintain spindle integrity during mitosis and interacts with the Mps1p kinase

We have identified a mutant allele of the DAM1 gene in a screen for mutations that are lethal in combination with the mps1-1 mutation. MPS1 encodes an essential protein kinase that is required for duplication of the spindle pole body and for the spindle assembly checkpoint. Mutations in six different genes were found to be lethal in combination with mps1-1, of which only DAM1 was novel. The remaining genes encode a checkpoint protein, Bub1p, and four chaperone proteins, Sti1p, Hsc82p, Cdc37p, and Ydj1p. DAM1 is an essential gene that encodes a protein recently described as a member of a microtubule binding complex. We report here that cells harboring the dam1-1 mutation fail to maintain spindle integrity during anaphase at the restrictive temperature. Consistent with this phenotype, DAM1 displays genetic interactions with STU1, CIN8, and KAR3, genes encoding proteins involved in spindle function. We have observed that a Dam1p-Myc fusion protein expressed at endogenous levels and localized by immunofluorescence microscopy, appears to be evenly distributed along short mitotic spindles but is found at the spindle poles at later times in mitosis.

Forced expiratory maneuvers in very young children. Assessment of flow limitation

The application of negative expiratory pressure (NEP) to the airway opening during forced expiratory maneuvers has recently been described as a noninvasive method to assess whether flow limitation is achieved in adults. This methodology has great potential for extending the measurement of forced expiratory maneuvers to young children who may not produce maximal efforts as reproducibly as adults. We used NEP to assess flow limitation in 10 children between 3 and 5 yr of age. NEP was well tolerated by all subjects. With the application of NEP, there was not a step increase in flow, a finding consistent with flow limitation for the subjects. In addition to visual inspection, we proposed a method to quantify the change in flow during a short NEP. The flow-volume curves obtained with and without NEP were visually the same, other than the flow transients produced by NEP. The calculated values of FVC and FEF25-75 were not significantly different when measured from flow- volume curves with and without NEP. There was a statistically significant increase in FEV1 with NEP; however, the group mean increase in FEV1 was less than 2%. We conclude that NEP may be a useful technique to determine whether flow limitation has been achieved in young children performing forced expiratory maneuvers.

Regional assignment and expression analysis of 29 expressed sequence tags mapped to chromosome 3

Of 311 expressed sequenced tags (ESTs) mapped to single human chromosomes by analysis of a monochromosome somatic cell hybrid panel, 29 were localized to chromosome 3. Analysis of somatic cell hybrid lines containing different regions of chromosome 3 has enabled the regional assignment of these 29 ESTs to 13 of 23 intervals covering chromosome 3. Northern analysis of 25 of the EST clones has provided information on the pattern of expression of potential genes represented by these transcripts in 16 human tissue types. Nine of the clones hybridized solely to a transcript(s) in the testis, 12 hybridized to transcripts in testis and other tissues, and 4 hybridized with transcripts in testis and other tissues but in addition have testis-specific transcript sizes. These ESTs will provide useful markers throughout chromosome 3 for the development of physical and transcription maps. In addition, they provide candidate genes for disease loci mapping to the intervals defined by the chromosome 3 deletion panel.

Characteristics of fresh and frozen-thawed red wolf (Canis rufus) spermatozoa

Ejaculates of the red wolf (Canis rufus) were evaluated immediately after collection and freeze-thawing to initiate a reproductive database for this endangered species. Electroejaculates from 13 adult red wolves collected during the breeding season (February-March; n=25; 1-3 collections/male) had a mean volume of 4.7+/-0.7 ml, 146.5+/-25.7 x 10(6) spermatozoa/ml and 71.2% motile spermatozoa. The mean proportion of cells with normal morphology was 73.6+/-3.2% (range, 20.3-93.7%), with 64% of ejaculates (16/25) containing 70-90% normal spermatozoa. The four most predominant abnormalities were a coiled flagellum (8.1%), a bent flagellum (4.7%), a bent midpiece with no cytoplasmic droplet (3.3%;), and a detached head defect (6.4%). After cooling in glycerolated extender, semen was frozen using a pelleting method on dry ice before plunging into liquid nitrogen. Pellets were thawed in phosphate buffered saline and examined for % sperm motility, normal morphology, viability and intact acrosomes. There was a decline (P < 0.05) in sperm motility (approximately 40%) and percentage of normal sperm (11.9%) after freezing, but no change in the proportion of viable cells. After freezing, there was a marked decline (P < 0.05) in the proportion of intact acrosomes from 74.5% to 55.5% which was accompanied by an increased proportion (P < 0.05) of partial acrosomes from 11.9% to 35.8%. These data demonstrate that, although red wolf spermatozoa can survive freeze-thawing using a technique common for domestic dog sperm, the finding of significant acrosome damage reveals (1) likely species specificity in the Canis genus and (2) the need for refining sperm cryopreservation technology for the red wolf.