This study evaluated the reliability of the Crowe and Hartofilakidis classification systems for developmental dysplasia of the hip in adults. Three experienced hip surgeons independently classified 209 osteoarthritic hips using both classification systems on two separate occasions. Inter-observer reliability was substantial to almost perfect, with kappa coefficients ranging from 0.85 to 0.93. Intra-observer reliability was also substantial to almost perfect, with kappa coefficients ranging from 0.80 to 0.95. Both classification systems demonstrated excellent reliability for assessing developmental dysplasia of the hip.
This study examined the impact of sarcopenia on long-term mortality in 200 patients who underwent endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms. Sarcopenia, defined as low skeletal muscle mass, was assessed on pre-operative CT scans. Patients with sarcopenia had significantly higher mortality rates than those without sarcopenia (76% vs 48%, p=0.016). On multivariate analysis, sarcopenia, hypertension, and older age were independent predictors of mortality following EVAR. The presence of sarcopenia on CT may help predict long-term survival in AAA patients undergoing EVAR.
This meta-analysis examined short-term and long-term mortality rates following elective open abdominal aortic aneurysm (AAA) repair versus endovascular aneurysm repair (EVAR) based on data from four randomized controlled trials with a total of 2783 patients. The analysis found that 30-day all-cause mortality was significantly higher for open repair compared to EVAR (3.2% vs 1.2%). However, there was no significant difference in long-term all-cause mortality between the two groups. Reintervention rates were higher following EVAR compared to open repair (18.9% vs 9.3%), but this finding was considered doubtful due to large heterogeneity. No significant differences were found between the
Does Multiple Axial Vein Incompetence Increase The Clinical Severity of Venou...Vein Global
By: Lowell S. Kabnick, MD, FACS
Visit VeinGlobal at http://www.veinglobal.com/ for more presentations and videos on this topic, or for more information on venous disease news, education and research.
ARA Poster: Pulmonary Hypertension in Systemic AutoimmunityGlenn Reeves
This study assessed the ability of exercise stress echocardiography to evaluate changes in pulmonary artery pressure in 197 patients with autoimmune diseases like systemic lupus erythematosus, limited systemic sclerosis, and diffuse systemic sclerosis. Stress echocardiography identified pulmonary artery hypertension in 80% of patients, with pressures rising significantly during exercise across all disease subgroups. Follow up testing in 51 patients over 12 months found pressures continued to rise significantly over time in all subgroups.
1) Medical helicopters have proliferated greatly in the US since the 1990s, doubling over the past decade, though their impact on patient outcomes is unclear.
2) Studies show medical helicopters can transport patients faster than ground ambulances, especially over long distances, but they are much more expensive, with costs 5-10 times higher than ground transport.
3) While helicopters may benefit some critically ill patients, many studies find no difference in outcomes between air and ground transport for most patients, calling into question whether higher costs of helicopters are justified given limited benefits for most cases.
This study aimed to develop a visual assessment tool to evaluate movement quality during the Star Excursion Balance Test (SEBT) and determine if poor movement quality predicts injury risk. Researchers had three physical therapists evaluate video recordings of 100 subjects performing the anterior reach of the SEBT. The therapists assessed trunk, pelvis, and knee movement on a scoring system and classified subjects as "at risk" or "not at risk" based on reach distances. Interrater reliability for movement scoring was poor to moderate except for the knee, which was moderate. While movement scores did not predict reach distances, subjects deemed "at risk" tended to have fewer movement faults. Knee assessment showed moderately strong specificity and poor sensitivity for detecting risk. Thus
Central Adiposity and Mortality after First-Ever Acute Ischemic StrokeErwin Chiquete, MD, PhD
Erwin Chiquete a José L. Ruiz-Sandoval c Luis Murillo-Bonilla e
Carolina León-Jiménez g Bertha Ruiz-Madrigal d, f Erika Martínez-López d, f
Sonia Román d, f Arturo Panduro d, f Alma Ramos b Carlos Cantú-Brito
Background: The waist-to-height ratio (WHtR) may be a better
adiposity measure than the body mass index (BMI). We
evaluated the prognostic performance of WHtR in patients
with acute ischemic stroke (AIS). Methods: First, we compared
WHtR and BMI as adiposity measures in 712 healthy
adults by tetrapolar bioimpedance analysis. Thereafter,
baseline WHtR was analyzed as predictor of 12-month allcause
mortality in 821 Mexican mestizo adults with first-ever
AIS by a Cox proportional hazards model adjusted for baseline
predictors. Results: In healthy individuals, WHtR correlated
higher than BMI with total fat mass and showed a higher
accuracy in identifying a high percentage of body fat (p <
0.01). In AIS patients a U-shaped relationship was observed
between baseline WHtR and mortality (fatality rate 29.1%).
On multivariate analysis, baseline WHtR ≤ 0.300 or >0.800 independently
predicted 12-month all-cause mortality (h
This study examined the impact of sarcopenia on long-term mortality in 200 patients who underwent endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms. Sarcopenia, defined as low skeletal muscle mass, was assessed on pre-operative CT scans. Patients with sarcopenia had significantly higher mortality rates than those without sarcopenia (76% vs 48%, p=0.016). On multivariate analysis, sarcopenia, hypertension, and older age were independent predictors of mortality following EVAR. The presence of sarcopenia on CT may help predict long-term survival in AAA patients undergoing EVAR.
This meta-analysis examined short-term and long-term mortality rates following elective open abdominal aortic aneurysm (AAA) repair versus endovascular aneurysm repair (EVAR) based on data from four randomized controlled trials with a total of 2783 patients. The analysis found that 30-day all-cause mortality was significantly higher for open repair compared to EVAR (3.2% vs 1.2%). However, there was no significant difference in long-term all-cause mortality between the two groups. Reintervention rates were higher following EVAR compared to open repair (18.9% vs 9.3%), but this finding was considered doubtful due to large heterogeneity. No significant differences were found between the
Does Multiple Axial Vein Incompetence Increase The Clinical Severity of Venou...Vein Global
By: Lowell S. Kabnick, MD, FACS
Visit VeinGlobal at http://www.veinglobal.com/ for more presentations and videos on this topic, or for more information on venous disease news, education and research.
ARA Poster: Pulmonary Hypertension in Systemic AutoimmunityGlenn Reeves
This study assessed the ability of exercise stress echocardiography to evaluate changes in pulmonary artery pressure in 197 patients with autoimmune diseases like systemic lupus erythematosus, limited systemic sclerosis, and diffuse systemic sclerosis. Stress echocardiography identified pulmonary artery hypertension in 80% of patients, with pressures rising significantly during exercise across all disease subgroups. Follow up testing in 51 patients over 12 months found pressures continued to rise significantly over time in all subgroups.
1) Medical helicopters have proliferated greatly in the US since the 1990s, doubling over the past decade, though their impact on patient outcomes is unclear.
2) Studies show medical helicopters can transport patients faster than ground ambulances, especially over long distances, but they are much more expensive, with costs 5-10 times higher than ground transport.
3) While helicopters may benefit some critically ill patients, many studies find no difference in outcomes between air and ground transport for most patients, calling into question whether higher costs of helicopters are justified given limited benefits for most cases.
This study aimed to develop a visual assessment tool to evaluate movement quality during the Star Excursion Balance Test (SEBT) and determine if poor movement quality predicts injury risk. Researchers had three physical therapists evaluate video recordings of 100 subjects performing the anterior reach of the SEBT. The therapists assessed trunk, pelvis, and knee movement on a scoring system and classified subjects as "at risk" or "not at risk" based on reach distances. Interrater reliability for movement scoring was poor to moderate except for the knee, which was moderate. While movement scores did not predict reach distances, subjects deemed "at risk" tended to have fewer movement faults. Knee assessment showed moderately strong specificity and poor sensitivity for detecting risk. Thus
Central Adiposity and Mortality after First-Ever Acute Ischemic StrokeErwin Chiquete, MD, PhD
Erwin Chiquete a José L. Ruiz-Sandoval c Luis Murillo-Bonilla e
Carolina León-Jiménez g Bertha Ruiz-Madrigal d, f Erika Martínez-López d, f
Sonia Román d, f Arturo Panduro d, f Alma Ramos b Carlos Cantú-Brito
Background: The waist-to-height ratio (WHtR) may be a better
adiposity measure than the body mass index (BMI). We
evaluated the prognostic performance of WHtR in patients
with acute ischemic stroke (AIS). Methods: First, we compared
WHtR and BMI as adiposity measures in 712 healthy
adults by tetrapolar bioimpedance analysis. Thereafter,
baseline WHtR was analyzed as predictor of 12-month allcause
mortality in 821 Mexican mestizo adults with first-ever
AIS by a Cox proportional hazards model adjusted for baseline
predictors. Results: In healthy individuals, WHtR correlated
higher than BMI with total fat mass and showed a higher
accuracy in identifying a high percentage of body fat (p <
0.01). In AIS patients a U-shaped relationship was observed
between baseline WHtR and mortality (fatality rate 29.1%).
On multivariate analysis, baseline WHtR ≤ 0.300 or >0.800 independently
predicted 12-month all-cause mortality (h
This study evaluated replacing the lateral scapula (LS) projection with a modified trauma axial (MTA) projection in the routine radiographic examination of acute shoulder injuries. A retrospective analysis of 244 shoulder examinations found that an anteroposterior (AP) view paired with an MTA projection identified 33 more traumatic abnormalities than an AP view paired with an LS projection. The MTA projection more clearly showed injuries like Hill-Sachs lesions, glenoid fractures, and fractures of the greater tuberosity. Additionally, the MTA projection had a lower estimated radiation dose than the LS projection. Therefore, the study recommends that the routine acute shoulder examination should include only AP and MTA projections.
This document summarizes the Ankylosing Spondylitis Databank Project in Taiwan led by Dr. James Cheng-Chung Wei. The project has collected clinical data and samples from over 3,000 visits by AS patients since 2003. Key findings include that over 90% of AS patients in Taiwan are HLA-B27 positive, and genetic studies of the project have identified genes associated with AS risk and severity. The database established through this long-term project aims to enable further research on AS pathogenesis and management.
Case-control Study on 2nd Hammertoe Deformity Correction TechniquesWenjay Sung
This is my case-control study on second hammertoe deformity correction techniques: arthroplasty, arthrodesis, and interpositional implant arthroplasty.
Rischke_Viscoelastic Disc Arthroplasty Provides Superior Back and Leg Pain Re...Kari Zimmers
This study compared outcomes of patients receiving a viscoelastic total disc replacement (VTDR) to patients receiving anterior lumbar interbody fusion (ALIF) for lumbar disc degeneration using data from two independent spine registries. Linear regression models showed that VTDR was associated with significantly greater back and leg pain relief compared to ALIF, with differences of 2.76 and 2.12 points respectively. Additional factors influencing pain relief included female sex, monosegmental surgery, higher preoperative pain levels, and surgical level. The results suggest that viscoelastic total disc replacement may provide superior pain relief compared to anterior lumbar interbody fusion for patients with degenerative lumbar disc disease.
1) Four speakers presented modern perspectives on the Six Determinants of Gait originally proposed in 1953, finding that some determinants have been disproven or require refinement based on new evidence.
2) One speaker found that flattening the vertical movement of the center of mass during walking does not reduce metabolic energy costs as originally thought.
3) Another speaker found preliminary data supports replacing two disproven determinants with equations relating peak vertical movement and acceleration to walking speed.
4) A third speaker found that heel rise at the end of stance can account for the reduction in vertical center of mass displacement during walking.
5) The last speaker proposed a mechanistic approach finding that redirecting the center of
Presentation given by Dr Saithna at the 2019 AANA (Arthroscopy Association North America) Annual Meeting on the Outcomes of Combined ACL and anterolateral ligament reconstruction in Professional Athletes
This document is a letter commenting on a recent review paper on hemodynamics in the microcirculation. The letter notes that while the review covered experimental studies in animals and computational modeling, it did not mention the considerable research that has been done measuring hemodynamics in the human microcirculation, specifically in the eye and nailfold. The letter provides over a dozen references to studies quantifying blood flow, velocity, and wall shear stress in the human conjunctiva, retina, and nailfold microvasculature using non-invasive imaging techniques. It also points out some technical issues with how some prior studies were summarized in the review paper.
The document compares the posterior approach (PA) and direct anterior approach (DAA) for total hip arthroplasty (THA). It finds that the DAA results in less muscle damage, less pain/narcotic use, earlier discharge from the hospital, and faster recovery of hip function and gait speed based on multiple studies. However, both approaches have similar risks of dislocation and comparable functional outcomes at one year post-operation. Patient factors like BMI, age, and compliance with hip precautions also impact outcomes.
This study compared outcomes of first metatarsophalangeal joint fusion using three different techniques: single lag screw fixation, lag screw with circlage wire fixation, and two compression Memory staples. 46 patients underwent one of the three procedures. Time to fusion and complication rates were compared. The Memory staples group had the shortest median time to fusion at 7.6 weeks and lowest nonunion rate, with no hardware-related problems. While no differences were statistically significant, the results suggest Memory staples may have advantages for first metatarsophalangeal joint fusion.
Austin Orthopedics is an open access, peer reviewed, scholarly journal dedicated to publish articles in all areas of orthopedics & muscular system. The renowned editorial team ensures a balanced, expert assessment of the articles published with an aim to provide a forum for physicians, researchers and other healthcare professionals to find most recent advances in all areas of orthopedics.
Austin Orthopedics accepts original research articles, review articles and short communication covering all aspects of orthopedics for review and possible publication.
Austin Orthopedics strongly supports the scientific up gradation and fortification in related scientific research community by enhancing access to peer reviewed scientific literary works. Austin Publishing Group also brings universally peer reviewed journals under one roof thereby promoting knowledge sharing, mutual promotion of multidisciplinary science.
This document contains abstracts from presentations at the 29th Annual Northeast Regional Scientific Meeting. The abstracts describe several studies involving nuclear imaging techniques:
1. A study evaluating the reproducibility of quantitative measurements from FDG PET and gallium scans in distinguishing between interstitial nephritis and acute tubular necrosis in rats. It found the measurements to be highly reproducible.
2. A case report describing how SPECT/CT imaging with indium-111 labeled white blood cells revealed unsuspected pulmonary septic emboli in a patient with infected hemodialysis access.
3. A case report where bone SPECT/CT identified an acute pelvic fracture that was missed on other imaging in a patient
The use of Z-scores in paediatric cardiology
Henry Chubb, John M Simpson
Department of Congenital Heart Disease, Evelina Children’s Hospital, Guy’s and St Thomas’ NHS Trust, London, UK
This study investigated the clinical outcomes and biomechanics of bi-unicondylar arthroplasty (Bi-UKA) compared to total knee arthroplasty (TKA) and healthy controls through three approaches:
1) Gait analysis found that Bi-UKA patients walked faster and with longer strides than TKA patients, exhibiting closer to normal gait patterns.
2) Patient-reported outcomes showed higher Oxford Knee Scores and quality of life scores for Bi-UKA patients compared to TKA patients.
3) A cadaveric study found that Bi-UKA preserved extensor efficiency of the knee better than TKA, particularly during gait.
Difference in Early Results Between Sub-Acute and Delayed ACL reconstruction:...Henrik Illerström
This randomized controlled trial compared outcomes of sub-acute ACL reconstruction (within 8 days of injury) versus delayed ACL reconstruction (6-10 weeks post-injury). At 3 months, there were no differences in range of motion between groups. At 6 months, the sub-acute group showed less thigh muscle atrophy and better functional strength on hop tests, though isokinetic strength was similar. Both groups improved significantly on KOOS scores after reconstruction, with no differences between groups. The study suggests sub-acute ACL reconstruction is safe and may help preserve strength compared to delayed reconstruction.
Effectiveness of Chin Tuck Against Resistance (CTAR) exercise in improving sw...Veera Bagu
Effectiveness of Chin Tuck Against Resistance (CTAR) exercise in improving swallowing ability among Cerebrovascular Accident patients with dysphagia at selected Hospital, Erode
Surgical Treatment of Haglund Triad by Using Complete Detachment and Reattach...skisnfeet
This study evaluated the surgical outcome of treating the Haglund triad, which includes retrocalcaneal exostosis, insertional Achilles tendinosis, and retrocalcaneal bursitis, using a standardized approach of complete detachment and reattachment of the Achilles tendon. Seventeen patients underwent this surgery and reported significant pain reduction, high satisfaction rates, and good functional outcomes post-operatively based on questionnaires and clinical scoring systems. Complications were few and minor in most cases.
This document discusses the use of technology such as robotic guidance systems and navigation in total hip arthroplasty (THA). It finds that while this technology can improve accuracy of cup placement, it has not been proven to improve clinical outcomes such as reducing dislocation rates or loosening. Functional issues like soft tissue tension that can cause instability are not addressed by technology. The document concludes that new technologies for THA have not proven themselves and further large investments in them should be analyzed carefully, as the procedure is already very successful without such technologies when performed through direct anterior approach.
Natural History of Associated Injuries in Chronic ACL Tearsctortho
This document summarizes a study of 60 anterior cruciate ligament (ACL) reconstruction patients at a US Army hospital in Germany over 2 years. It found that on average there was a 30 day delay between injury and initial presentation to a primary care provider, and a 151 day delay between that initial presentation and orthopedic evaluation. Arthroscopic evaluation during reconstruction found lateral compartment damage in 33% of patients, medial compartment damage in 50% of patients, with meniscal tears being the most common associated injury. The study concludes that these findings confirm that chronic ACL insufficiency can lead to increased meniscal tears and cartilage damage over time.
New standards of weight and body composition by frame size and heigth for ass...Alejandra Licea
This document presents new standards for assessing nutritional status in adults and elderly populations based on anthropometric measurements from two large national health surveys. The study establishes percentiles for weight, skinfold thickness, and muscle area by height, sex, frame size (determined by elbow breadth), and age group (25-54 years and 55-74 years). These new standards can be used to identify those at risk of obesity or undernutrition compared to peers of the same height, sex, frame size, and age. The standards are meant to provide a more accurate evaluation of nutritional status that accounts for individual variability in body size.
A catheter is a thin tube made from medical grade materials that serve a broad range of functions, but mainly catheters are medical devices that can be inserted in the body to treat disease or perform surgical procedures. Catheters have been inserted into body cavities, ducts, or vessels to allow for drainage, administration of therapeutic fluids or gases, operational access for surgery. Catheters help perform tasks in various systems such as cardiovascular, urological, gastrointestinal, neurovascular, and ophthalmic systems. A dataset of 12 patients with varying “weights” and “heights” was recorded along with the lengths of their catheter tubes. This data set was found from two revered statistical textbooks on linear regression and the Department of Scientific Computing at Florida State University. This data set was not able to be linked to any particular clinical or experimental research studies, but the data set can be used to help catheter manufacturers and medical professionals better decide on what particular catheter lengths to use for patients knowing only their height & weight. These research insights could be helpful to healthcare professionals that have patients with incomplete or no healthcare records
to decide what catheter length to use. The main investigative inquiry that needed to be answered was how does patient weight & height influence catheter length together and separately? We conducted linear regression and other statistical analysis procedures in R program & Microsoft Excel and discovered that this data exhibited a quality called multi collinearity. With multi collinearity, all predictors (2 or more
independent variables) are not significant in an all encompassing linear aggression, but the predictors might be significant in their own individual linear regressions. Individual linear regression analyses were conducted for both patient height & weight to see how much they both contribute to varying catheter length. Patient weight was found to be more impatful than patient height in relationship to catheter length, even though height and weight are a classical example of multi collinearity predictors.
Statistical quality control in cervical vaginal cythology: ASC-US/SIL RatioRolando Alvarado Anchisi
This document summarizes a study on statistical quality control of cervical-vaginal cytology diagnoses in Panama. The study analyzed 58,289 cytology samples from 2008 to 2015. It found 974 samples were diagnosed as ASC-US and 925 as SIL. The average ASC-US/SIL ratio was 1.16. ASC-US diagnoses represented 1.67% of samples on average, and SIL diagnoses 1.59%. There were some yearly variations that were attributed to human factors. The percentages and ratios found were below literature references. The conclusions were that conventional cytology is still effective, and comparing results to other Panamanian labs could help determine if the findings are typical for the region.
This study evaluated replacing the lateral scapula (LS) projection with a modified trauma axial (MTA) projection in the routine radiographic examination of acute shoulder injuries. A retrospective analysis of 244 shoulder examinations found that an anteroposterior (AP) view paired with an MTA projection identified 33 more traumatic abnormalities than an AP view paired with an LS projection. The MTA projection more clearly showed injuries like Hill-Sachs lesions, glenoid fractures, and fractures of the greater tuberosity. Additionally, the MTA projection had a lower estimated radiation dose than the LS projection. Therefore, the study recommends that the routine acute shoulder examination should include only AP and MTA projections.
This document summarizes the Ankylosing Spondylitis Databank Project in Taiwan led by Dr. James Cheng-Chung Wei. The project has collected clinical data and samples from over 3,000 visits by AS patients since 2003. Key findings include that over 90% of AS patients in Taiwan are HLA-B27 positive, and genetic studies of the project have identified genes associated with AS risk and severity. The database established through this long-term project aims to enable further research on AS pathogenesis and management.
Case-control Study on 2nd Hammertoe Deformity Correction TechniquesWenjay Sung
This is my case-control study on second hammertoe deformity correction techniques: arthroplasty, arthrodesis, and interpositional implant arthroplasty.
Rischke_Viscoelastic Disc Arthroplasty Provides Superior Back and Leg Pain Re...Kari Zimmers
This study compared outcomes of patients receiving a viscoelastic total disc replacement (VTDR) to patients receiving anterior lumbar interbody fusion (ALIF) for lumbar disc degeneration using data from two independent spine registries. Linear regression models showed that VTDR was associated with significantly greater back and leg pain relief compared to ALIF, with differences of 2.76 and 2.12 points respectively. Additional factors influencing pain relief included female sex, monosegmental surgery, higher preoperative pain levels, and surgical level. The results suggest that viscoelastic total disc replacement may provide superior pain relief compared to anterior lumbar interbody fusion for patients with degenerative lumbar disc disease.
1) Four speakers presented modern perspectives on the Six Determinants of Gait originally proposed in 1953, finding that some determinants have been disproven or require refinement based on new evidence.
2) One speaker found that flattening the vertical movement of the center of mass during walking does not reduce metabolic energy costs as originally thought.
3) Another speaker found preliminary data supports replacing two disproven determinants with equations relating peak vertical movement and acceleration to walking speed.
4) A third speaker found that heel rise at the end of stance can account for the reduction in vertical center of mass displacement during walking.
5) The last speaker proposed a mechanistic approach finding that redirecting the center of
Presentation given by Dr Saithna at the 2019 AANA (Arthroscopy Association North America) Annual Meeting on the Outcomes of Combined ACL and anterolateral ligament reconstruction in Professional Athletes
This document is a letter commenting on a recent review paper on hemodynamics in the microcirculation. The letter notes that while the review covered experimental studies in animals and computational modeling, it did not mention the considerable research that has been done measuring hemodynamics in the human microcirculation, specifically in the eye and nailfold. The letter provides over a dozen references to studies quantifying blood flow, velocity, and wall shear stress in the human conjunctiva, retina, and nailfold microvasculature using non-invasive imaging techniques. It also points out some technical issues with how some prior studies were summarized in the review paper.
The document compares the posterior approach (PA) and direct anterior approach (DAA) for total hip arthroplasty (THA). It finds that the DAA results in less muscle damage, less pain/narcotic use, earlier discharge from the hospital, and faster recovery of hip function and gait speed based on multiple studies. However, both approaches have similar risks of dislocation and comparable functional outcomes at one year post-operation. Patient factors like BMI, age, and compliance with hip precautions also impact outcomes.
This study compared outcomes of first metatarsophalangeal joint fusion using three different techniques: single lag screw fixation, lag screw with circlage wire fixation, and two compression Memory staples. 46 patients underwent one of the three procedures. Time to fusion and complication rates were compared. The Memory staples group had the shortest median time to fusion at 7.6 weeks and lowest nonunion rate, with no hardware-related problems. While no differences were statistically significant, the results suggest Memory staples may have advantages for first metatarsophalangeal joint fusion.
Austin Orthopedics is an open access, peer reviewed, scholarly journal dedicated to publish articles in all areas of orthopedics & muscular system. The renowned editorial team ensures a balanced, expert assessment of the articles published with an aim to provide a forum for physicians, researchers and other healthcare professionals to find most recent advances in all areas of orthopedics.
Austin Orthopedics accepts original research articles, review articles and short communication covering all aspects of orthopedics for review and possible publication.
Austin Orthopedics strongly supports the scientific up gradation and fortification in related scientific research community by enhancing access to peer reviewed scientific literary works. Austin Publishing Group also brings universally peer reviewed journals under one roof thereby promoting knowledge sharing, mutual promotion of multidisciplinary science.
This document contains abstracts from presentations at the 29th Annual Northeast Regional Scientific Meeting. The abstracts describe several studies involving nuclear imaging techniques:
1. A study evaluating the reproducibility of quantitative measurements from FDG PET and gallium scans in distinguishing between interstitial nephritis and acute tubular necrosis in rats. It found the measurements to be highly reproducible.
2. A case report describing how SPECT/CT imaging with indium-111 labeled white blood cells revealed unsuspected pulmonary septic emboli in a patient with infected hemodialysis access.
3. A case report where bone SPECT/CT identified an acute pelvic fracture that was missed on other imaging in a patient
The use of Z-scores in paediatric cardiology
Henry Chubb, John M Simpson
Department of Congenital Heart Disease, Evelina Children’s Hospital, Guy’s and St Thomas’ NHS Trust, London, UK
This study investigated the clinical outcomes and biomechanics of bi-unicondylar arthroplasty (Bi-UKA) compared to total knee arthroplasty (TKA) and healthy controls through three approaches:
1) Gait analysis found that Bi-UKA patients walked faster and with longer strides than TKA patients, exhibiting closer to normal gait patterns.
2) Patient-reported outcomes showed higher Oxford Knee Scores and quality of life scores for Bi-UKA patients compared to TKA patients.
3) A cadaveric study found that Bi-UKA preserved extensor efficiency of the knee better than TKA, particularly during gait.
Difference in Early Results Between Sub-Acute and Delayed ACL reconstruction:...Henrik Illerström
This randomized controlled trial compared outcomes of sub-acute ACL reconstruction (within 8 days of injury) versus delayed ACL reconstruction (6-10 weeks post-injury). At 3 months, there were no differences in range of motion between groups. At 6 months, the sub-acute group showed less thigh muscle atrophy and better functional strength on hop tests, though isokinetic strength was similar. Both groups improved significantly on KOOS scores after reconstruction, with no differences between groups. The study suggests sub-acute ACL reconstruction is safe and may help preserve strength compared to delayed reconstruction.
Effectiveness of Chin Tuck Against Resistance (CTAR) exercise in improving sw...Veera Bagu
Effectiveness of Chin Tuck Against Resistance (CTAR) exercise in improving swallowing ability among Cerebrovascular Accident patients with dysphagia at selected Hospital, Erode
Surgical Treatment of Haglund Triad by Using Complete Detachment and Reattach...skisnfeet
This study evaluated the surgical outcome of treating the Haglund triad, which includes retrocalcaneal exostosis, insertional Achilles tendinosis, and retrocalcaneal bursitis, using a standardized approach of complete detachment and reattachment of the Achilles tendon. Seventeen patients underwent this surgery and reported significant pain reduction, high satisfaction rates, and good functional outcomes post-operatively based on questionnaires and clinical scoring systems. Complications were few and minor in most cases.
This document discusses the use of technology such as robotic guidance systems and navigation in total hip arthroplasty (THA). It finds that while this technology can improve accuracy of cup placement, it has not been proven to improve clinical outcomes such as reducing dislocation rates or loosening. Functional issues like soft tissue tension that can cause instability are not addressed by technology. The document concludes that new technologies for THA have not proven themselves and further large investments in them should be analyzed carefully, as the procedure is already very successful without such technologies when performed through direct anterior approach.
Natural History of Associated Injuries in Chronic ACL Tearsctortho
This document summarizes a study of 60 anterior cruciate ligament (ACL) reconstruction patients at a US Army hospital in Germany over 2 years. It found that on average there was a 30 day delay between injury and initial presentation to a primary care provider, and a 151 day delay between that initial presentation and orthopedic evaluation. Arthroscopic evaluation during reconstruction found lateral compartment damage in 33% of patients, medial compartment damage in 50% of patients, with meniscal tears being the most common associated injury. The study concludes that these findings confirm that chronic ACL insufficiency can lead to increased meniscal tears and cartilage damage over time.
New standards of weight and body composition by frame size and heigth for ass...Alejandra Licea
This document presents new standards for assessing nutritional status in adults and elderly populations based on anthropometric measurements from two large national health surveys. The study establishes percentiles for weight, skinfold thickness, and muscle area by height, sex, frame size (determined by elbow breadth), and age group (25-54 years and 55-74 years). These new standards can be used to identify those at risk of obesity or undernutrition compared to peers of the same height, sex, frame size, and age. The standards are meant to provide a more accurate evaluation of nutritional status that accounts for individual variability in body size.
A catheter is a thin tube made from medical grade materials that serve a broad range of functions, but mainly catheters are medical devices that can be inserted in the body to treat disease or perform surgical procedures. Catheters have been inserted into body cavities, ducts, or vessels to allow for drainage, administration of therapeutic fluids or gases, operational access for surgery. Catheters help perform tasks in various systems such as cardiovascular, urological, gastrointestinal, neurovascular, and ophthalmic systems. A dataset of 12 patients with varying “weights” and “heights” was recorded along with the lengths of their catheter tubes. This data set was found from two revered statistical textbooks on linear regression and the Department of Scientific Computing at Florida State University. This data set was not able to be linked to any particular clinical or experimental research studies, but the data set can be used to help catheter manufacturers and medical professionals better decide on what particular catheter lengths to use for patients knowing only their height & weight. These research insights could be helpful to healthcare professionals that have patients with incomplete or no healthcare records
to decide what catheter length to use. The main investigative inquiry that needed to be answered was how does patient weight & height influence catheter length together and separately? We conducted linear regression and other statistical analysis procedures in R program & Microsoft Excel and discovered that this data exhibited a quality called multi collinearity. With multi collinearity, all predictors (2 or more
independent variables) are not significant in an all encompassing linear aggression, but the predictors might be significant in their own individual linear regressions. Individual linear regression analyses were conducted for both patient height & weight to see how much they both contribute to varying catheter length. Patient weight was found to be more impatful than patient height in relationship to catheter length, even though height and weight are a classical example of multi collinearity predictors.
Statistical quality control in cervical vaginal cythology: ASC-US/SIL RatioRolando Alvarado Anchisi
This document summarizes a study on statistical quality control of cervical-vaginal cytology diagnoses in Panama. The study analyzed 58,289 cytology samples from 2008 to 2015. It found 974 samples were diagnosed as ASC-US and 925 as SIL. The average ASC-US/SIL ratio was 1.16. ASC-US diagnoses represented 1.67% of samples on average, and SIL diagnoses 1.59%. There were some yearly variations that were attributed to human factors. The percentages and ratios found were below literature references. The conclusions were that conventional cytology is still effective, and comparing results to other Panamanian labs could help determine if the findings are typical for the region.
This study aimed to correlate knee height with body height and develop regression equations to estimate body height from knee height measurements in subjects from North India. The study measured the body height and knee height of 1000 healthy subjects aged 18 and older. Knee height was found to be positively correlated with body height. Regression analyses were used to generate equations to estimate body height based on knee height, with separate equations for males and females that also included age as a predictor variable. The equations were intended to provide a more accurate estimation of body height that is less affected by age-related changes.
Clinical and epidemiological profile of patients undergoing total hip arthro...David Sadigursky
Clinical and epidemiological profile of patients undergoing total hip arthroplasty.
Rheumatology and Orthopedic Medicine
Rheumatol Orthop Med, 2017 doi: 10.15761/ROM.1000120
This study aimed to determine if matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) could serve as biomarkers for estimating the probability of complicated appendicitis in pediatric patients. The study analyzed MMP and TIMP levels in 331 pediatric patients with confirmed appendicitis. A decision tree was generated using several biomarkers that best predicted complicated appendicitis, with test characteristics showing clinical utility. When tested on a separate cohort, the decision tree performed well at classifying patients' risk, and had superior accuracy compared to white blood cell count alone. The results suggest MMPs and TIMPs may help identify which patients are appropriate for non-operative management of appendicitis.
This document presents clinical guidelines for veterinary cardiopulmonary resuscitation (CPR) in dogs and cats based on an evidence-based review. A total of 101 individual guidelines were developed across five domains: preparedness and prevention, basic life support, advanced life support, monitoring, and post-cardiac arrest care. The guidelines were reviewed by veterinary professionals and refined. A CPR algorithm and resuscitation drug-dosing scheme were also created to standardize CPR procedures and minimize interruptions to chest compressions. While knowledge gaps remain, the guidelines provide an evidence-based approach to veterinary CPR for the first time. Further evaluation is still needed to assess the impact of the guidelines on CPR
This document compares outcomes of anterior cervical discectomy fusion (ACDF) and anterior cervical corpectomy fusion (ACCF) for treating multi-level cervical spondylosis. It retrospectively analyzed 80 patients who underwent either multi-level ACDF (42 patients) or single/multi-level ACCF (38 patients) using titanium mesh cages filled with autograft and anterior cervical plates. The ACCF group had significantly higher blood loss and lower operative time than the ACDF group. Both groups showed equivalent improvement in symptoms, with fusion rates over 90% and maintained cervical lordosis. However, the ACCF group had a higher rate of early hardware failures and pseudarthroses.
1) The study evaluated 55 children treated with Pavlik harnesses for developmental dysplasia of the hip (DDH) to identify early ultrasound predictors of late acetabular dysplasia or avascular necrosis.
2) Three sonographic findings on initial ultrasounds predicted late sequelae: a dynamic coverage index of 22% or less, an alpha angle less than 43 degrees, and abnormal echogenicity of the cartilaginous roof.
3) Abnormal echogenicity of the cartilaginous roof was the most specific single predictor, with a sensitivity of 100% and specificity of 88% for residual dysplasia.
1) The study evaluated 55 children treated with Pavlik harnesses for developmental dysplasia of the hip (DDH) to identify early ultrasound predictors of late acetabular dysplasia or avascular necrosis.
2) Three sonographic findings on initial ultrasounds predicted late sequelae: a dynamic coverage index of 22% or less, an alpha angle less than 43 degrees, and abnormal echogenicity of the cartilaginous roof.
3) Abnormal echogenicity of the cartilaginous roof, indicating early transformation of the roof cartilage, was the most specific single predictor of residual dysplasia after Pavlik harness treatment.
This study examined the correlation between body height and cranial measurements in 800 medical students (400 male, 400 female) aged 17-25 years in North India. Cranial length and breadth were measured and found to be significantly larger in males than females. A positive correlation was found between height and cranial dimensions in both sexes. Regression equations were derived that could estimate height from cranial length or breadth measurements. Precision estimates for height and cranial dimension measurements showed a high degree of accuracy. The results indicate cranial dimensions could help estimate height, which has importance for anthropology and forensic sciences.
This study aimed to determine the correlation between stature and cranial measurements in a population from North India. Cranial length, breadth, and height were measured on 800 medical students aged 17-25 years. Regression analyses found significant positive correlations between stature and both cranial length and breadth for both males and females. Regression equations were generated that could estimate stature based on cranial measurements, which the authors concluded could be useful for forensic and anthropological applications when only skull remains are available. Measurement reliability was high, with technical error of less than 0.5 cm. The study provides population-specific equations for estimating height from cranial dimensions in North Indians.
This study examined the correlation between body height and cranial measurements in 800 medical students (400 male, 400 female) aged 17-25 years in North India. Cranial length and breadth were measured and found to be significantly larger in males than females. A positive correlation was found between height and cranial dimensions in both sexes. Regression equations were derived that could estimate height from cranial length or breadth measurements. Precision estimates for height and cranial dimension measurements showed a high degree of accuracy. The results indicate cranial dimensions could help estimate height, which has importance for anthropology and forensic sciences.
This study examined the relationship between lumbar scoliosis and osteoporosis in postmenopausal women. The researchers analyzed dual-energy x-ray absorptiometry (DXA) scans of 900 randomly selected postmenopausal women aged 64-88 years old. They measured the Cobb angle to assess lumbar scoliosis and bone mineral density at the femoral neck, total hip, and spine to assess osteoporosis. They found that both the incidence and degree of lumbar scoliosis, defined as a Cobb angle over 10 degrees, increased significantly with age. However, after adjusting for covariates like age, weight and ethnicity, there was no significant association between bone mineral density at any site and the Cobb angle.
This study examined the relationship between hormone replacement therapy (HRT) use and osteoarthritis (OA) in women. The study analyzed radiographic data from 1003 women and found that current HRT users had a 3-fold lower risk of knee OA compared to never users. Current HRT use was also associated with a non-significant reduced risk of distal interphalangeal OA. No clear protective effect was seen for carpometacarpal OA. Past HRT use showed weaker or no protective effects. The results suggest HRT may have a protective effect against OA when used continuously but not after stopping use. Larger prospective studies are still needed to confirm these findings.
This study introduces a template scoring system to evaluate alternate right ventricular pacing sites based on fluoroscopic imaging. The scoring system measures the angle of lead attachment on a left anterior oblique view. Testing in 23 patients found that increasing the loop of lead in the right ventricle altered the angle of attachment by 6 to 32 degrees on average, but the score typically remained within the same template zone. The template aims to standardize evaluation of pacing lead positioning but requires further validation.
This document provides 10 recommendations for transparent and consistent scientific research and publication. It recommends (1) stating the research question and purpose, (2) describing the data source and sample size, (3) presenting individual observations when possible, (4) reporting numbers, averages, and variation when data is aggregated, (5) describing statistical methods used, (6) addressing assumptions of those methods, (7) distinguishing statistical and practical significance and clarifying hypotheses, (8) presenting confidence intervals rather than just p-values, (9) explaining departures from conventional significance levels, and (10) ensuring conclusions are consistent with the statistical rigor. The document emphasizes using clear and precise language to describe methodology, results, and conclusions.
Clinical Trials Versus Health Outcomes Research: SAS/STAT Versus SAS Enterpri...cambridgeWD
Clinical trials and health outcomes research differ in important ways that impact statistical modeling approaches. Clinical trials typically use homogeneous samples and focus on a single endpoint, while health outcomes data is heterogeneous with multiple endpoints. Predictive modeling techniques used in health outcomes research, like those in SAS Enterprise Miner, are better suited than traditional methods as they can handle complex real-world data without strong assumptions and more accurately predict rare events. Validation of models on separate test data is also important for generalizing results.
Clinical Trials Versus Health Outcomes Research: SAS/STAT Versus SAS Enterpri...cambridgeWD
This document discusses the differences between clinical trials and health outcomes research. Clinical trials use homogeneous samples, surrogate endpoints, and focus on a single outcome. They are also typically underpowered for rare events. Health outcomes research uses heterogeneous data from the general population to examine multiple real endpoints simultaneously. It has larger samples and data that allow analysis of rare occurrences. Predictive modeling is better suited than traditional statistical methods for analyzing heterogeneous health outcomes data due to relaxed assumptions like normality.
Statistics For Data Analytics - Multiple & logistic regression Shrikant Samarth
Task: To build multiple regression and logistic regression models on appropriate data.
Approach: A general topic was selected first after which the data was downloaded from the source keeping the restrictions in mind and then cleaned in R. Then the multiple regression and logistic regression models were built using IBM SPSS and the outputs were interpreted. The dependent variable was life expectancy and the independent variables were Age-standardized Mortality-Communicable”, “Age-standardized Mortality-Cardiovascular Disease and Diabetes".
Findings: Multipleregression - analysis was conducted to make sure normality, linearity, multi-collinearity, independence of errors and homoscedasticity were not violated. Statistically, the score of Life expectancy at age 60, 퐹(2,102) = 39.474 푅2 = .436, 푝 < 0.0005
Logistic Regression: Result shows 58.9% (Cox & Snell R-Square) and 80.1% (Nagelkerke R-Square) of the variance and gives 92.4% of correctly classified countries. The two indicating factors made a remarkable commitment to the model. Also, the model predicts the increase in “Mortality-Cardiovascular/Diabetes” and “Mortality rate cause by Communicable” variables is the cause of a decrease in Life Expectancy in a country.
Tools: IBM SPSS
This study analyzed the prevalence of bovine aortic arch configurations in patients with and without thoracic aortic pathology. The researchers reviewed over 800 computed tomography scans and found that 31% of patients had some form of bovine arch. Specifically, 15% had a Type I bovine arch and 16% had a Type II. When comparing 156 patients with thoracic aortic dissection or aneurysm to controls, the study found those with pathology were more likely to have a Type II bovine arch. They concluded that patients with bovine arch configurations may be associated with higher levels of thoracic aortic disease.
Similar to Crowe y hartofilakidis classification ddc in adults (20)
The binding of cosmological structures by massless topological defectsSérgio Sacani
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
When I was asked to give a companion lecture in support of ‘The Philosophy of Science’ (https://shorturl.at/4pUXz) I decided not to walk through the detail of the many methodologies in order of use. Instead, I chose to employ a long standing, and ongoing, scientific development as an exemplar. And so, I chose the ever evolving story of Thermodynamics as a scientific investigation at its best.
Conducted over a period of >200 years, Thermodynamics R&D, and application, benefitted from the highest levels of professionalism, collaboration, and technical thoroughness. New layers of application, methodology, and practice were made possible by the progressive advance of technology. In turn, this has seen measurement and modelling accuracy continually improved at a micro and macro level.
Perhaps most importantly, Thermodynamics rapidly became a primary tool in the advance of applied science/engineering/technology, spanning micro-tech, to aerospace and cosmology. I can think of no better a story to illustrate the breadth of scientific methodologies and applications at their best.
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
The technology uses reclaimed CO₂ as the dyeing medium in a closed loop process. When pressurized, CO₂ becomes supercritical (SC-CO₂). In this state CO₂ has a very high solvent power, allowing the dye to dissolve easily.
Phenomics assisted breeding in crop improvementIshaGoswami9
As the population is increasing and will reach about 9 billion upto 2050. Also due to climate change, it is difficult to meet the food requirement of such a large population. Facing the challenges presented by resource shortages, climate
change, and increasing global population, crop yield and quality need to be improved in a sustainable way over the coming decades. Genetic improvement by breeding is the best way to increase crop productivity. With the rapid progression of functional
genomics, an increasing number of crop genomes have been sequenced and dozens of genes influencing key agronomic traits have been identified. However, current genome sequence information has not been adequately exploited for understanding
the complex characteristics of multiple gene, owing to a lack of crop phenotypic data. Efficient, automatic, and accurate technologies and platforms that can capture phenotypic data that can
be linked to genomics information for crop improvement at all growth stages have become as important as genotyping. Thus,
high-throughput phenotyping has become the major bottleneck restricting crop breeding. Plant phenomics has been defined as the high-throughput, accurate acquisition and analysis of multi-dimensional phenotypes
during crop growing stages at the organism level, including the cell, tissue, organ, individual plant, plot, and field levels. With the rapid development of novel sensors, imaging technology,
and analysis methods, numerous infrastructure platforms have been developed for phenotyping.
Authoring a personal GPT for your research and practice: How we created the Q...Leonel Morgado
Thematic analysis in qualitative research is a time-consuming and systematic task, typically done using teams. Team members must ground their activities on common understandings of the major concepts underlying the thematic analysis, and define criteria for its development. However, conceptual misunderstandings, equivocations, and lack of adherence to criteria are challenges to the quality and speed of this process. Given the distributed and uncertain nature of this process, we wondered if the tasks in thematic analysis could be supported by readily available artificial intelligence chatbots. Our early efforts point to potential benefits: not just saving time in the coding process but better adherence to criteria and grounding, by increasing triangulation between humans and artificial intelligence. This tutorial will provide a description and demonstration of the process we followed, as two academic researchers, to develop a custom ChatGPT to assist with qualitative coding in the thematic data analysis process of immersive learning accounts in a survey of the academic literature: QUAL-E Immersive Learning Thematic Analysis Helper. In the hands-on time, participants will try out QUAL-E and develop their ideas for their own qualitative coding ChatGPT. Participants that have the paid ChatGPT Plus subscription can create a draft of their assistants. The organizers will provide course materials and slide deck that participants will be able to utilize to continue development of their custom GPT. The paid subscription to ChatGPT Plus is not required to participate in this workshop, just for trying out personal GPTs during it.
The use of Nauplii and metanauplii artemia in aquaculture (brine shrimp).pptxMAGOTI ERNEST
Although Artemia has been known to man for centuries, its use as a food for the culture of larval organisms apparently began only in the 1930s, when several investigators found that it made an excellent food for newly hatched fish larvae (Litvinenko et al., 2023). As aquaculture developed in the 1960s and ‘70s, the use of Artemia also became more widespread, due both to its convenience and to its nutritional value for larval organisms (Arenas-Pardo et al., 2024). The fact that Artemia dormant cysts can be stored for long periods in cans, and then used as an off-the-shelf food requiring only 24 h of incubation makes them the most convenient, least labor-intensive, live food available for aquaculture (Sorgeloos & Roubach, 2021). The nutritional value of Artemia, especially for marine organisms, is not constant, but varies both geographically and temporally. During the last decade, however, both the causes of Artemia nutritional variability and methods to improve poorquality Artemia have been identified (Loufi et al., 2024).
Brine shrimp (Artemia spp.) are used in marine aquaculture worldwide. Annually, more than 2,000 metric tons of dry cysts are used for cultivation of fish, crustacean, and shellfish larva. Brine shrimp are important to aquaculture because newly hatched brine shrimp nauplii (larvae) provide a food source for many fish fry (Mozanzadeh et al., 2021). Culture and harvesting of brine shrimp eggs represents another aspect of the aquaculture industry. Nauplii and metanauplii of Artemia, commonly known as brine shrimp, play a crucial role in aquaculture due to their nutritional value and suitability as live feed for many aquatic species, particularly in larval stages (Sorgeloos & Roubach, 2021).
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...Sérgio Sacani
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
2. 580 C. K. YIANNAKOPOULOS, A. CHOUGLE, A. ESKELINEN, J. P. HODGKINSON, G. HARTOFILAKIDIS
THE JOURNAL OF BONE AND JOINT SURGERY
new evaluation. The observers were blinded to the previous
order of the radiographs and assessment was performed
independently. Interobserver variability was measured by
comparing the ratings of all observers on each occasion,
while intra-observer reliability was determined by compar-
ing the two assessments of each observer.
Sample-size estimation.9
The intraclass correlation coeffi-
cient is often used as an index of reliability in a measure-
ment study.
It may be thought of as the correlation between any two
observations made on the same subject. When this correla-
tion is high, the observations on a subject tend to match,
and the measurement reliability is high. Calculation of the
sample size was based on the primary outcome with the aim
of showing a reliability which was at least substantial
(kappa value > 0.7)10
and the power was set to 80%. Addi-
tionally, the minimum value of kappa deemed to be clini-
cally important was 0.4 with a proportion of positive
ratings of 0.9. The sample size required for two raters was
180 according to Sim and Wright.9
Statistical analysis. Assessment of inter- and intra-observer
consistency was accomplished by the use of the kappa coef-
ficient (κ) as proposed by Fleiss.10
Interobserver agreement
was assessed by calculating kappa coefficients for each pos-
sible pair of observers. Intra-observer agreement was
assessed by calculating kappa coefficients for each pair of
evaluations.
According to Landis and Koch,11
agreement was graded
as slight (κ = 0 to 0.2), fair (κ = 0.21 to 0.40), moderate
(κ = 0.41 to 0.60), substantial (κ = 0.61 to 0.80) or almost
perfect (κ = 0.81 to 1.0).
Table I. Description of the Crowe1
and Hartofilakidis3
classification systems of congenital hip disease in adults
Classification Type Description
Anatomy of the acetabulum as verified during
surgery
Crowe I Proximal displacement < 0.1% of pelvic height or
less than 50% subluxation
II Displacement of 0.10% to 0.15% or subluxation
50% to 75%
III Displacement of 0.15% to 0.20% or
subluxation 75% to 100%
IV Displacement > 0.20% or subluxation > 100%
Hartofilakidis Dysplasia The femoral head is contained within the
original acetabulum despite the degree of
subluxation
Segmental deficiency of the superior wall
Secondary shallowness due to fossa-covering
osteophyte
Low dislocation The femoral head articulates with a false
acetabulum which partially covers the true
acetabulum to a varying degree
Complete absence of the superior wall
Anterior and posterior segmental deficiency
Narrow opening and inadequate depth of the true
acetabulum
High dislocation The femoral head is completely out of the true
acetabulum and migrated superiorly and
posteriorly to a varying degree
Segmental deficiency of the entire acetabulum with
narrow opening
Inadequate depth
Excessive anteversion
Abnormal distribution of bone stock, mainly located
superioposteriorly in relation to the true acetabulum
Fig. 1
Radiograph showing measurements for the Crowe classification
system (A, vertical distance between the reference interteardrop
line (line 1) and the head-neck junction (line 2); B, vertical dis-
tance between the line connecting the ischial tuberosities (line
3) and the line connecting the iliac crests (line 4).
3. INTER- AND INTRA-OBSERVER VARIABILITY OF THE CROWE AND HARTOFILAKIDIS CLASSIFICATION SYSTEMS 581
VOL. 90-B, No. 5, MAY 2008
All tests were two-sided and statistical significance was
set at p £ 0.05. All analyses were carried out using the sta-
tistical package SPSS version 13.0 (SPSS Inc., Chicago, Illi-
nois) and the STATA statistical software (StataCorp LP,
College Station, Texas).
Results
All hips were classified and the agreement among the
reviewers is shown in Table II. At the first examination, all
agreed on the rating in 83.73% of cases with regard to
the Crowe classification and in 84.68% with regard to
the Hartofilakidis classification. At the second examina-
tion agreement was 78.47% and 79.9%, respectively. In
no case was there complete disagreement among the
reviewers.
In the first evaluation, paired comparisons showed an
interobserver unweighted kappa coefficient ranging from
0.84 to 0.86 for the Croweclassification and 0.79 to 0.90
for the Hartofilakidis classification (Table III). The kappa
coefficient with linear weighting ranged from 0.90 to 0.92
for the Crowe classification and 0.85 to 0.93 for the
Hartofilakidis classification.
Fig. 2a
Radiographs showing the Hartofilakidis classification system describing three types of increasing severity of the deformity, i.e.
dysplasia, low and high dislocation. a) In type-A deformity (dysplasia) the femoral head is contained within the original acetab-
ulum, b) in type-B deformity (low dislocation) it articulates with a false acetabulum which partially covers the true acetabulum
and c) in type-C deformity (high dislocation) the femoral head has migrated superiorly and posteriorly to the hypoplastic true
acetabulum.
Fig. 2b Fig. 2c
Table II. Agreement among the reviewers with regard to the Crowe1
and Hartofilakidis3
classifications by number and percentage
First examination Second examination
Agreement Crowe Hartofilakidis Crowe Hartofilakidis
All three reviewers 175 (83.73) 177 (84.68) 164 (78.47) 167 (79.9)
Two reviewers 34 (16.26) 32 (15.31) 45 (21.53) 42 (20.1)
No agreement 0 0 0 0
Table III. Paired comparisons of interobserver agreement for the Crowe and Hartofilakidis classifications giving the unweighted
and linearly-weighted kappa coefficient values and the SEM in parentheses
First evaluation Second evaluation
Observer pair
Unweighted kappa
coefficient
Kappa with linear
weighting
Observed
agreement (%)
Unweighted
kappa coefficient
Kappa with linear
weighting
Observed
agreement (%)
Crowe
A/B 0.84 (0.03) 0.91 (0.01) 89.5 0.75 (0.04) 0.85 (0.02) 82.0
A/C 0.83 (0.03) 0.90 (0.02) 89.8 0.71 (0.04) 0.83 (0.02) 79.7
B/C 0.86 (0.03) 0.92 (0.02) 91.0 0.82 (0.03) 0.90 (0.02) 88.0
Hartofilakidis
A/B 0.79 (0.03) 0.85 (0.02) 86.6 0.77 (0.03) 0.84 (0.02) 87.0
A/C 0.80 (0.03) 0.90 (0.01) 87.0 0.66 (0.04) 0.75 (0.03) 77.5
B/C 0.90 (0.02) 0.93 (0.01) 93.8 0.66 (0.04) 0.75 (0.03) 77.5
4. 582 C. K. YIANNAKOPOULOS, A. CHOUGLE, A. ESKELINEN, J. P. HODGKINSON, G. HARTOFILAKIDIS
THE JOURNAL OF BONE AND JOINT SURGERY
In the second evaluation, paired comparisons showed
an interobserver unweighted kappa coefficient ranging
from 0.71 to 0.82 for the Crowe classification and 0.66 to
0.77 for the Hartofilakidis classification (Table III). The
kappa coefficient with linear weighting ranged from 0.83
to 0.90 for the Crowe classification and 0.75 to 0.84 for
the Hartofilakidis classification.6
The unweighted kappa coefficients between the two
evaluations of the same observer ranged from 0.77 to 0.91
for the Crowe classification and 0.76 to 0.91 for the
Hartofilakidis classification.6
The kappa values with
linear weighting were 0.86 to 0.95 for the Crowe classifi-
cation and 0.80 to 0.93 for the Hartofilakidis classifica-
tion (Table IV).
Discussion
The results of our study confirm that both the Crowe and
the Hartofilakidis classification systems show excellent reli-
ability, as judged by the inter- and intra-observer variability.
They are simple to use and are reliable and reproducible.12-18
Several factors may affect inter- and intra-observer reliabil-
ity such as the experience of the raters,19
ambiguity of the
system, interval between readings and additional imaging
modalities. The use of standard evaluation forms and
radiographs may reduce the extent of variability. Similarly,
agreement may be improved by using advanced imaging
techniques, such as CT or MRI.20
The limitations of the Crowe classification are the require-
ment of a radiograph of the whole pelvis and the variability
of locating the femoral head-neck junction with rotation of
the limb. The main limitation of the Hartofilakidis classifica-
tion is the difficulty in classifying borderline cases of dys-
plasia and low dislocation, and low and high dislocation.
The Crowe classification describes the proximal migra-
tion of the femoral head regardless of theacetabular defor-
mity and assumes that there is a direct relationship between
the amount of migration and the severity of disease.
Although this hypothesis is usually valid this is not always
so. The Hartofilakidis classification relies on the anatomy
of the acetabulum as encountered during surgery. If there is
difficulty in classifying borderline cases, CT can clarify the
anatomical variation.21
In some studies it had been assumed that Crowe types I
and II correspond to Hartofilakidis type I, Crowe type III to
Hartofilakidis type II and Crowe type IV to Hartofilakidis
type III.22,23
This assumption is not always valid because
the anatomy of the acetabulum is variable and the amount
of migration is not a definite criterion by which to judge the
type of dysplasia.
Both classifications were compared recently by Decking
et al.24
Three observers of different experience (one con-
sultant, one resident and one medical student) evaluated
the radiographs of 51 patients (62 hips) on two occasions.
A high inter- and intra-observer reliability of both systems
was demonstrated. In our study a significantly higher
number of hips was included (209 hips) and the three
raters were experienced hip surgeons who understood the
two systems and were more competent to estimate the
bone deficiencies encountered intra-operatively. The reli-
ability of a classification system depends on the consis-
tency of measurements or observations and relates to the
quality of the measurement or observation.25
It also
depends on the extent of agreement between repeated
measurements. A reliable system classifies a disease or
fracture consistently, but does not necessarily show what
is happening.26,27
A valid classification system gives the
underlying pathology of the disease or configuration
of the fracture and is therefore closer to the ‘truth’ of what
is being measured or described. Reliability and validity
are not independent, but are related.28
A method may be
reliable if it measures something consistently, but is valid
only if the results of measurement approximates to the
true value. A classification system therefore may be reli-
able but not valid and cannot be valid without being
reliable.26
Systems relying on poorly-described features
may inherently perform poorly on reliability analyses
because the observers cannot identify them accurately.
The Hartofilakidis system can predict in a reliable and
reproducible manner the bone deficiencies encountered
during total hip replacement from pre-operative radio-
graphs.
The interpretation of kappa values is based on conven-
tion. Landis and Koch11
proposed that a value > 0.80 rep-
resented excellent agreement between observers, but
Fleiss10
and Svanholm et al28
suggested that a value > 0.75
indicated excellent agreement. In our study both systems
showed high inter- and intra-observer agreement, with
weighted kappa values > 0.75. An inherent characteristic
of the evaluation of classification systems using the kappa
coefficient is that it depends on the prevalence of each type
of classification, that is, more common types are expected
to show greater agreement.12
Also, kappa depends on the
Table IV. Intra-observer agreement for the Crowe and Hartofilakidis classifications giving the unweighted and linearly-weighted kappa
coefficient values and the SEM in parentheses
Crowe classification Hartofilakidis classification
Observer pair
Unweighted kappa
coefficient
Kappa with linear
weighting
Observed
agreement (%)
Unweighted kappa
coefficient
Kappa with linear
weighting
Observed
agreement (%)
A/A 0.77 (0.03) 0.86 (0.02) 83.6 0.84 (0.03) 0.80 (0.02) 90.0
B/B 0.90 (0.02) 0.95 (0.01) 93.4 0.76 (0.03) 0.83 (0.02) 84.7
C/C 0.91 (0.02) 0.95 (0.01) 94.2 0.91 (0.02) 0.93 (0.01) 95.3
5. INTER- AND INTRA-OBSERVER VARIABILITY OF THE CROWE AND HARTOFILAKIDIS CLASSIFICATION SYSTEMS 583
VOL. 90-B, No. 5, MAY 2008
number of categories in each system, with a tendency for
a lower value as the number of categories increases, as in
the Crowe system. The interobserver variation must be
considered when designing protocols for multicentre clin-
ical trials.
In conclusion, both systems are reproducible and repeat-
able for experienced observers and can be used for the eval-
uation of the dysplastic hip. The quantitative Crowe
classification does not require knowledge of the anatomy
of a dysplastic hip whereas the qualitative Hartofilakidis
classification provides insight into the structural changes
which will be encountered at operation. The two systems
evaluate the hip from a different perspective and can be
combined for research or operating purposes.
No benefits in any form have been received or will be received from a commer-
cial party related directly or indirectly to the subject of this article.
References
1. Crowe JF, Mani VJ, Ranawat CS. Total hip replacement in congenital dislocation
and dysplasia of the hip. J Bone Joint Surg [Am] 1979;61-A:15-23.
2. Eftekhar NS. Total hip arthroplasty. St. Louis: CV Mosby, 1993:925.
3. Hartofilakidis G, Stamos K, Ioannidis TT. Low friction arthroplasty for old
untreated congenital dislocation of the hip. J Bone Joint Surg [Br] 1988;70-B:182-6.
4. Hartofilakidis G, Stamos K, Karachalios T, Ioannidis TT, Zacharakis N. Con-
genital hip disease in adults: classification of acetabular deficiencies and operative
treatment with acetabuloplasty combined with total hip arthroplasty. J Bone Joint
Surg [Am] 1996;78-A:683-92.
5. Kerboul M, Mathieu M, Sauzieres P. Total hip replacement for congenital disloca-
tion of the hip. In: Postel M, Kerboul M, Evrard J, Courpied JP. Total hip replacement.
New York: Springer, 1987.
6. Chougle A, Hemmady MV, Hodgkinson JP. Severity of hip dysplasia and loosen-
ing of the socket in cemented total hip replacement: a long-term follow-up. J Bone
Joint Surg [Br] 2005;87-B:16-20.
7. Chougle A, Hemmady MV, Hodgkinson JP. Long-term survival of the acetabular
component after total hip arthroplasty with cement in patients with developmental
dysplasia of the hip. J Bone Joint Surg [Am] 2006;88-A:71-9.
8. Eskelinen A, Helenius I, Remes V, et al. Cementless total hip arthroplasty in
patients with high congenital hip dislocation. J Bone Joint Surg [Am] 2006;88-A:80-
91.
9. Sim J, Wright CC. The kappa statistics in reliability studies: use, interpretation and
sample size requirement. Phys Ther 2005;85:257-68.
10. Fleiss JL. Statistical methods for rates and proportions. Second ed. New York: John
Wiley & Sons, 1981:218.
11. Landis JR, Koch GG. The measurement of observer agreement for categorical data.
Biometrics 1977;33:159-74.
12. Blundell CM, Parker MJ, Pryor GA, Hopkinson-Woolley J, Bhonsle SS.
Assessment of the AO classification of intracapsular fractures of the proximal femur.
J Bone Joint Surg [Br] 1998;80-B:679-83.
13. Flinkkilä T, Nikkola-Sihto A, Kaarela O, Pääkkö E, Raatikainen T. Poor inter-
observer reliability of AO classification of fractures of the distal radius: additional
computed tomography is of minor value. J Bone Joint Surg [Br] 1998;80-B:670-2.
14. Humphrey CA, Dirschl DR, Ellis TJ. Interobserver reliability of a CT-based fracture
classification system. J Orthop Trauma 2005;19:616-22.
15. Wainwright AM, Williams JR, Carr AJ. Interobserver and intraobserver variation
in classification systems for fractures of the distal humerus. J Bone Joint Surg [Br]
2000;82-B:636-42.
16. Malek IA, Machani B, Mevcha AM, Hyder NH. Inter-observer reliability and
intra-observer reproducibility of the Weber classification of ankle fractures. J Bone
Joint Surg [Br] 2006;88-B:1204-6.
17. Brorson S, Bagger J, Sylvest A, Hrøbjartsson A. Improved interobserver varia-
tion after training of doctors in the Neer system: a randomised trial. J Bone Joint Surg
[Br] 2002;84-B:950-4.
18. Bhattacharya R, Vassan UT, Finn P, Port A. Sanders classification of fractures of
the os calcis: an analysis of inter- and intra-observer variability. J Bone Joint Surg [Br]
2005;87-B:205-8.
19. Beaulé PE, Dorey FJ, Matta JM. Letournel classification for acetabular fractures:
assessment of interobserver and intraobserver reliability. J Bone Joint Surg [Am]
2003;85-A:1704-9.
20. Doornberg J, Lindenhovius A, Kloen P, et al. Two and three-dimensional com-
puted tomography for the classification and management of distal humeral fractures:
evaluation of reliability and diagnostic accuracy. J Bone Joint Surg [Am] 2006;88-
A:1795-801.
21. Hartofilakidis G, Karachalios T. Total hip arthroplasty for congenital hip disease. J
Bone Joint Surg [Am] 2004;86-A:242-50.
22. Rozykdal Z, Janicek P, Smid Z. Total hip replacement with the CLS expansion shell
and a structural femoral head autograft for patients with congenital hip disease. J
Bone Joint Surg [Am] 2005;87-A:801-7.
23. Jarosynski G, Woodgate IG, Saleh KJ, Gross AE. Total hip replacement for the
dislocated hip. J Bone Joint Surg [Am] 2001;83-A:272.
24. Decking R, Brunner A, Decking J, Puhl W, Günther KP. Reliability of the Crowe
and Hartofilakidis classifications used in the assessment of the adult dysplastic hip.
Skeletal Radiol 2006;35:282-7.
25. Garbuz DS, Masri BA, Esdaile J, Duncan CP. Classification systems in ortho-
paedics. J Am Acad Orthop Surg 2002;10:290-7.
26. Greenfield ML, Kuhn JE, Wojtys EM. A statistics primer: validity and reliability.
Am J Sports Med 1998;26:483-5.
27. Kocher MS, Zurakowski D. Clinical epidemiology and biostatistics: a primer for
orthopaedic surgeons. J Bone Joint Surg [Am] 2004;86-A:607-20.
28. Svanholm H, Starklint H, Gundersen HJ, et al. Reproducibility of histomorpho-
logic diagnoses with special reference to the kappa statistic. APMIS 1989;97:689-98.