scholarly journals Congenital pseudarthrosis of the tibia: biological and biomechanical considerations to achieve union and prevent refracture

2019 ◽  
Vol 13 (2) ◽  
pp. 120-133 ◽  
Author(s):  
D. Paley
Keyword(s):  
Bone Morphogenic Protein ◽  
Level Of Evidence ◽  
Cross Sectional ◽  
Congenital Pseudarthrosis ◽  
Proximal Migration ◽  
The Mean ◽  
The Cross ◽  
Both Bones ◽  
Primary Union ◽  
Biomechanical Factors

Congenital pseudarthrosis of the tibia (CPT) is likely to be a primary periosteal disease and secondary bone disease. The primary goal of treatment is to obtain union, correct the diaphyseal deformity, correct any proximal fibular migration and prevent refracture. The pathobiology demonstrates increased osteoclasis by the surrounding fibrous hamartoma and reduced osteogenesis and bone morphogenic protein production by the bone. This leads to a loss of remodelling potential and gradual bowing and atrophy of the bone with eventual fracture of the tibia and or fibula. This recommends the synergistic use of bisphosphonates and bone morphogenic protein. The pathomechanics of CPT implicate the anterolateral bowing, narrow diameter of the atrophic bone ends and proximal fibular migration. These biomechanical factors can be addressed by means of straightening of the deformity, intramedullary support of both bones, stable fixation and reduction of proximal migration of the fibula. A summary of the literature on CPT shows that the mean probability of achieving primary union without refracture, by most treatments is 50% (12% to 80%). Two recent studies have shown a much higher success rate approaching 100%, by creating a cross-union between the tibia and fibula. The cross-union with intramedullary reinforcement of the bone makes refracture unlikely due to the cross-sectional area of union with its two-bar linkage. A new classification to guide such treatment is also proposed. Level of Evidence V – expert opinion

Cross-sectional area of the ulnar nerve after decompression at the cubital tunnel

2016 ◽  
Vol 41 (8) ◽  
pp. 838-842 ◽  
Author(s):  
S. Duetzmann ◽  
K. G. Krishnan ◽  
F. Staub ◽  
J.-S. Kang ◽  
V. Seifert ◽  
...  
Keyword(s):  
Ulnar Nerve ◽  
Cross Sectional Area ◽  
Cubital Tunnel ◽  
Slight Reduction ◽  
Sectional Area ◽  
Level Of Evidence ◽  
Cross Sectional ◽  
The Mean ◽  
The Cross

A total of 48 patients undergoing surgical decompression of the ulnar nerve at the cubital tunnel between February 2010 and May 2013 were retrospectively studied to determine changes in the cross-sectional area of the nerve by the technique of neurosonography. The mean follow-up was 46 months. Post-operative follow-up examination of the cross-sectional area of the ulnar nerve showed a slight reduction in the mean value from 13.8 mm2 (pre-operative) to 12.9 mm2 (post-operative). Of the 48 patients, 36 showed a reduction in the cross-sectional area. No correlation was detected between the clinical and sonographic outcomes. Ultrasound seems to be of limited value in the post-operative assessment of patients with entrapment neuropathy of the ulnar nerve. Level of Evidence: IV

Deep Cheek Fat Volumes and Midfacial Aging

2019 ◽  
Vol 40 (5) ◽  
pp. 467-475 ◽  
Author(s):  
Jacob I Tower ◽  
Neil A Gordon ◽  
Boris Paskhover
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Longitudinal Analysis ◽  
Linear Regression Analysis ◽  
Ct Scans ◽  
Level Of Evidence ◽  
Cross Sectional ◽  
The Mean ◽  
The Cross ◽  
Fat Volume

Abstract Background Midfacial volumizing procedures are increasingly common in facial rejuvenation. However, the changes that occur in midfacial fat with aging are poorly understood. Objectives The aim of this study was to determine how deep cheek fat volume is predicted by age. Methods We conducted retrospective cross-sectional and longitudinal studies of patients based on facial computed tomography (CT) scans. In the cross-sectional cohort, multiple linear regression analysis was performed to model the relations between age and deep cheek fat volumes. In the longitudinal analysis, changes to deep cheek fat volumes were tracked among subjects who underwent multiple facial CT scans. Results The cross-sectional cohort comprised 109 patients. The mean (SD) age of the subjects was 59.7 (15.0) years (range, 21.7-91.1 years). A linear regression analysis showed that increasing age was associated with increasing deep cheek fat volume (β = 0.015, P < 0.001). Additional regression analyses showed that the gain of fat with aging was more pronounced in the caudal aspect of the cheek (β = 0.007, P < 0.001) than in the cephalad (β = 0.005, P < 0.001). Twenty-three subjects were identified for longitudinal analysis. The mean (SD) ages at initial and final imaging time points were 50.0 (5.8) and 60.3 (5.2) years. In the deep fat compartment, there was an average gain of 0.23 mL over 10.3 years (P = 0.03). Conclusions Age is an important predictor of midfacial deep cheek fat volume. In this study, there is no evidence of adipose volume loss in the deep cheek compartment. Rather, aging was associated with an increase in deep cheek fat, possibly reflecting pseudoherniation of buccal fat. Level of Evidence 2

scholarly journals Atrophy patterns in isolated subscapularis lesions

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Gernot Seppel ◽  
Andreas Voss ◽  
Daniel J. H. Henderson ◽  
Simone Waldt ◽  
Bernhard Haller ◽  
...  
Keyword(s):  
Muscle Atrophy ◽  
Area Ratio ◽  
Cross Sectional Area ◽  
Control Group ◽  
Sectional Area ◽  
Cross Sectional ◽  
Subscapularis Muscle ◽  
Mri Scans ◽  
The Mean ◽  
The Cross

Abstract Background While supraspinatus atrophy can be described according to the system of Zanetti or Thomazeau there is still a lack of characterization of isolated subscapularis muscle atrophy. The aim of this study was to describe patterns of muscle atrophy following repair of isolated subscapularis (SSC) tendon. Methods Forty-nine control shoulder MRI scans, without rotator cuff pathology, atrophy or fatty infiltration, were prospectively evaluated and subscapularis diameters as well as cross sectional areas (complete and upper half) were assessed in a standardized oblique sagittal plane. Calculation of the ratio between the upper half of the cross sectional area (CSA) and the total CSA was performed. Eleven MRI scans of patients with subscapularis atrophy following isolated subscapularis tendon tears were analysed and cross sectional area ratio (upper half /total) determined. To guarantee reliable measurement of the CSA and its ratio, bony landmarks were also defined. All parameters were statistically compared for inter-rater reliability, reproducibility and capacity to quantify subscapularis atrophy. Results The mean age in the control group was 49.7 years (± 15.0). The mean cross sectional area (CSA) was 2367.0 mm2 (± 741.4) for the complete subscapularis muscle and 1048.2 mm2 (± 313.3) for the upper half, giving a mean ratio of 0.446 (± 0.046). In the subscapularis repair group the mean age was 56.7 years (± 9.3). With a mean cross sectional area of 1554.7 mm2 (± 419.9) for the complete and of 422.9 mm2 (± 173.6) for the upper half of the subscapularis muscle, giving a mean CSA ratio of 0.269 (± 0.065) which was seen to be significantly lower than that of the control group (p < 0.05). Conclusion Analysis of typical atrophy patterns of the subscapularis muscle demonstrates that the CSA ratio represents a reliable and reproducible assessment tool in quantifying subscapularis atrophy. We propose the classification of subscapularis atrophy as Stage I (mild atrophy) in case of reduction of the cross sectional area ratio < 0.4, Stage II (moderate atrophy) in case of < 0.35 and Stage III (severe atrophy) if < 0.3.

Morphological Variations and Normal Parameters of the Cross-Sectional Anatomy of the Tibiofibular Syndesmotic

2021 ◽  
pp. 193864002110552
Author(s):  
Seyed Ali Hashemi ◽  
Soheil Nosrati ◽  
Zahra Shayan ◽  
Amir Reza Vosoughi
Keyword(s):  
Tibiofibular Syndesmosis ◽  
Normal Range ◽  
Level Of Evidence ◽  
Cross Sectional ◽  
Morphological Variations ◽  
Upper Limit ◽  
Significant Difference ◽  
P 16 ◽  
Axial Ct ◽  
The Cross

Background: The aim of this study was to determine morphological variations and normal parameters of the cross-sectional tibiofibular syndesmotic anatomy. Methods: Configurations of syndesmosis, anterior syndesmotic width (ASW), posterior syndesmotic width (PSW), and overlap distance, defined as the overlap of medial fibula with a drawn line from tip of anterior tubercle of incisura fibularis to the posterior tip, were measured on normal computed tomography (CT) scans of 110 cases. Results: Seventy seven male (70%) and 33 female (30%) (left: 50 and right: 60) were assessed. Mean age of the cases was 33 ± 13 (range: 15-80) years. Three different syndesmotic configurations were crescent (55.5%), rectangular (39.1 %), and semicircle (5.4 %). Overall, mean ASW, PSW, and overlap distance were 2.72, 3.98, and 1.02 mm, respectively. Upper limit of normal ASW in crescent, rectangular, and semicircle was 4.80, 4.85, and 3.89 mm, respectively. The maximum of PSW in crescent, rectangular, and semicircle was 6.25, 6.50, and 4.97 mm, respectively. There was not significant difference between syndesmotic configurations based on age (P = .69) and sex (P = .16). Conclusions: During interpreting axial CT scan to diagnose syndesmotic injuries, the normal range of parameters according to the different configurations of the tibiofibular syndesmosis should be carefully considered. Level of Evidence: Level 4

scholarly journals FUNCTIONAL INDEPENDENCE OF PEDIATRIC PATIENTS WITH MUCOPOLYSACCHARIDOSES

2019 ◽  
Vol 27 (4) ◽  
pp. 212-215
Author(s):  
Paloma Silva Lopes ◽  
Diógenes Pires Serra Filho ◽  
Marcos Antônio Almeida Matos
Keyword(s):  
Pediatric Patients ◽  
Case Series ◽  
Functional Independence Measure ◽  
Functional Independence ◽  
Cross Sectional Study ◽  
Cognitive Domain ◽  
Level Of Evidence ◽  
Cross Sectional ◽  
Documentary Analysis ◽  
The Mean

ABSTRACT Objective: To measure the functional independence to perform activities of daily living of pediatric patients diagnosed with mucopolysaccharidoses. Methods: A descriptive cross-sectional study was carried out with the population of pediatric patients with a confirmed enzymatic diagnosis of mucopolysaccharidoses, enrolled in the Orthopedics outpatient clinic of a hospital in the State of Bahia. The data were collected between October 2016 and March 2017, based on the documentary analysis of the assessment forms used in the department. The variables of this study comprised sex, age, type of MPS and level of functional independence, measured by the Functional Independence Measure scale. Results: Twenty-six patients participated in the study. These were predominantly male (61.5%), with a mean age of 10 ± 4.5 years, affected by MPS VI (73.1%). In the motor domain, the mean score was 65 (± 19.9 points); the cognitive domain obtained a mean score equal to 28 (± 8.2 points); and the total FIM score was 93 (± 26.5). Conclusion: Impaired functional independence was observed among children and adolescents with mucopolysaccharidoses. Tasks related to dressing, toileting, bathing, problem solving and social interaction were those that required the most assistance and/or supervision. Level of Evidence IV, Case Series.

scholarly journals Establishing User Error on the Patient-Reported Component of the American Shoulder and Elbow Surgeons Shoulder Score

2020 ◽  
Vol 8 (3) ◽  
pp. 232596712091009
Author(s):  
Jonathan Bourget-Murray ◽  
Ariana Frederick ◽  
Lisa Murphy ◽  
Jacqui French ◽  
Shane Barwood ◽  
...  
Keyword(s):  
Total Error ◽  
Cross Sectional Study ◽  
Patient Reported Outcome ◽  
Error Rates ◽  
Sectional Study ◽  
Level Of Evidence ◽  
Cross Sectional ◽  
Total Error Rate ◽  
Patient Reported ◽  
The Mean

Background: The American Shoulder and Elbow Surgeons (ASES) score is a patient-reported outcome (PRO) questionnaire developed to facilitate communication among international investigators and to allow comparison of outcomes for patients with shoulder disabilities. Although this PRO measure has been deemed easy to read and understand, patients may make mistakes when completing the questionnaire. Purpose: To evaluate the frequency of potential mistakes made by patients completing the ASES score. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A prospective cross-sectional study was performed for 600 ASES questionnaires completed by patients upon their first visit to 1 of 2 clinic locations (Australian vs Canadian site). Two categories of potential errors were predefined, and then differences in error rates were compared based on demographics (age, sex, and location). To determine whether these methods were reliable, an independent, third reviewer evaluated a subset of questionnaires separately. The interrater reliability was evaluated through use of the Cohen kappa. Results: The mean patient age was 49.9 years, and 63% of patients were male. The Cohen kappa was high for both evaluation methods used, at 0.831 and 0.918. On average, 17.9% of patients made at least 1 potential mistake, while an additional 10.4% of patients corrected their own mistakes. No differences in total error rate were found based on baseline demographics. Canadians and Australians had similar rates of error. Conclusion: To ensure the accuracy of the ASES score, this questionnaire should be double checked, as potential mistakes are too frequently made. This attentiveness will ensure that the ASES score remains a valid, reliable, and responsive tool to be used for further shoulder research.

Evaluation of Reduction Accuracy of Suture-Button and Screw Fixation Techniques for Syndesmotic Injuries

2016 ◽  
Vol 37 (12) ◽  
pp. 1317-1325 ◽  
Author(s):  
Onur Kocadal ◽  
Mehmet Yucel ◽  
Murad Pepe ◽  
Ertugrul Aksahin ◽  
Cem Nuri Aktekin
Keyword(s):  
Screw Fixation ◽  
Ct Scans ◽  
Functional Evaluation ◽  
Level Of Evidence ◽  
Cross Sectional ◽  
Suture Button ◽  
Fixation Group ◽  
Significant Difference ◽  
The Mean

Background: Among the most important predictors of functional results of treatment of syndesmotic injuries is the accurate restoration of the syndesmotic space. The purpose of this study was to investigate the reduction performance of screw fixation and suture-button techniques using images obtained from computed tomography (CT) scans. Methods: Patients at or below 65 years who were treated with screw or suture-button fixation for syndesmotic injuries accompanying ankle fractures between January 2012 and March 2015 were retrospectively reviewed in our regional trauma unit. A total of 52 patients were included in the present study. Fixation was performed with syndesmotic screws in 26 patients and suture-button fixation in 26 patients. The patients were divided into 2 groups according to the fixation methods. Postoperative CT scans were used for radiologic evaluation. Four parameters (anteroposterior reduction, rotational reduction, the cross-sectional syndesmotic area, and the distal tibiofibular volumes) were taken into consideration for the radiologic assessment. Functional evaluation of patients was done using the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scale at the final follow-up. The mean follow-up period was 16.7 ± 11.0 months, and the mean age was 44.1 ± 13.2. Results: There was a statistically significant decrease in the degree of fibular rotation ( P = .03) and an increase in the upper syndesmotic area ( P = .006) compared with the contralateral limb in the screw fixation group. In the suture-button fixation group, there was a statistically significant increase in the lower syndesmotic area ( P = .02) and distal tibiofibular volumes ( P = .04) compared with the contralateral limbs. The mean AOFAS scores were 88.4 ± 9.2 and 86.1 ± 14.0 in the suture-button fixation and screw fixation group, respectively. There was no statistically significant difference in the functional ankle joint scores between the groups. Conclusion: Although the functional outcomes were similar, the restoration of the fibular rotation in the treatment of syndesmotic injuries by screw fixation was troublesome and the volume of the distal tibiofibular space increased with the suture-button fixation technique. Level of Evidence: Level III, retrospective comparative study.

scholarly journals Information Percolation

2010 ◽  
Vol 2 (1) ◽  
pp. 100-111 ◽  
Author(s):  
Darrell Duffie ◽  
Gaston Giroux ◽  
Gustavo Manso
Keyword(s):  
Rate Of Convergence ◽  
Explicit Solution ◽  
Common Interest ◽  
Cross Sectional ◽  
Individual Agent ◽  
Large Market ◽  
The Mean ◽  
The Cross ◽  
Over Time

We study the “percolation” of information of common interest through a large market as agents encounter and reveal information to each other over time. We provide an explicit solution for the dynamics of the cross-sectional distribution of posterior beliefs. We also show that convergence of the cross-sectional distribution of beliefs to a common posterior is exponential and that the rate of convergence does not depend on the size of the groups of agents that meet. The rate of convergence is merely the mean rate at which an individual agent is matched. (JEL D83)

scholarly journals Cross Sectional Area of the Achilles Tendon in a Prospective Cohort of an Elite Military Population

2017 ◽  
Vol 2 (3) ◽  
pp. 2473011417S0002
Author(s):  
Kevin Martin ◽  
Laura Dawson ◽  
Jeffrey Wake
Keyword(s):  
Achilles Tendon ◽  
Prospective Cohort ◽  
Military Training ◽  
Cross Sectional Area ◽  
Service Members ◽  
Sectional Area ◽  
Cross Sectional ◽  
The Mean ◽  
Multiple Levels ◽  
The Cross

Category: Ankle, Hindfoot Introduction/Purpose: The prevalence of Achilles tendon pathology is common in many sports and daily activities. From ruptures to overuse injuries resulting in tendonopathies, AT dysfunction can result in disability and reduced productively. Continued research that increases our knowledge base of normal Achilles tendon properties can improve our ability to reduce and prevent future AT injuries. In this study, we examined the cross-sectional area (CSA) of the Achilles tendon (AT) at multiple levels in an asymptomatic population of elite American military service members that participate in greater than 20 hours of intense training per week. Methods: We conducted a prospective cohort study composed of 41 active duty United States Army Rangers. The Rangers are a specialized infantry organization that participates in extensive military training and rigorous combat missions. The service members were voluntarily recruited to participate while deployed in a combat theater. All subjects were members of the Ranger Regiment participating in greater than 20 hours of intense bipedal non-sport weekly training with no history of AT pathology. In a standing position, each subject had bilateral Achilles insertion marked along with additional skin markings made at 2 cm, 4 cm, and 6 cm above the AT insertion. At all four levels, the AT was measured in the coronal and sagittal plains using ultrasound. Results: In 41 subjects, a total of 82 Achilles tendons were examined. The mean age of the cohort was 26 years, 70 inches tall, with a mean weight of 187 pounds. The mean sagittal thickness of the AT at the insertion was 4.3 mm, 2 cm above the insertion is was 4.3 mm, 4 cm above the insertion is was 4.2 mm, and at 6 cm above the insertion it was 4 mm. In the coronal plain was 19.1 mm, 14.3 mm, 13.5 mm, and 14.4 mm respectively. The cross-sectional area was calculated at each respective level: 0.65 cm2, 0.48 cm2, 0.44 cm2 and 0.45 cm2. The non-dominant ankle was slightly larger at each level but was not found to be statistically significant. Conclusion: These results provide the mean sagittal and coronal diameters of the Achilles tendon as measured by ultrasound throughout the watershed area of a young active adult male population. Our data also suggest that increased non-sport activity may not increase the cross-sectional area of the Achilles tendon. Identifying the normal diameter at multiple levels throughout the most commonly injured area can potentially improve the provider’s ability to identify early disease processes and apply targeted interventions to help slow or prevent progression and possible rupture.

scholarly journals Effects of Wet-Pressing and Cross-Linking on the Tensile Properties of Carbon Nanotube Fibers

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2170 ◽  
Author(s):  
Hyunjung Cho ◽  
Jinwoo Lee ◽  
Haemin Lee ◽  
Sung-Hyun Lee ◽  
Junbeom Park ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Cross Linking ◽  
Cross Sectional ◽  
Specific Strength ◽  
Wet Pressing ◽  
Mean Size ◽  
The Mean ◽  
The Cross ◽  
Carbon Nanotube Fibers ◽  
Physical And Chemical

To increase the strength of carbon nanotube (CNT) fibers (CNTFs), the mean size of voids between bundles of CNTs was reduced by wet-pressing, and the CNTs were cross-linked. Separate and simultaneous physical (roller pressing) and chemical methods (cross-linking) were tested to confirm each method’s effects on the CNTF strength. By reducing the fraction of pores, roller pressing decreased the cross-sectional area from 160 μm2 to 66 μm2 and increased the average load-at-break from 2.83 ± 0.25 cN to 4.41 ± 0.16 cN. Simultaneous injection of crosslinker and roller pressing augmented the cross-linking effect by increasing the infiltration of the crosslinker solution into the CNTF, so the specific strength increased from 0.40 ± 0.05 N/tex to 0.67 ± 0.04 N/tex. To increase the strength by cross-linking, it was necessary that the size of the pores inside the CNTF were reduced, and the infiltration of the solution was increased. These results suggest that combined physical and chemical treatment is effective to increase the strength of CNTFs.

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