THE SIZE AND POSITIONAL RELATIONSHIP OF THE MEDIAL PATELLOFEMORAL LIGAMENT IN EARLY PEDIATRIC DEVELOPMENT

Background: Knowledge of the medial patellofemoral ligament (MPFL) size and positional relationship to the articular cartilage is not well understood in pediatrics. The purpose of this study was to analyze the size and position of the MPFL relative to the articular surface of the pediatric patella. Methods: 39 pediatric cadaveric knee specimens (age range 1 month-11 years, 24 male) were dissected by fellowship-trained, pediatric orthopedic surgeons to expose the MPFL insertion to the patella (Figure 1A). Digital calipers (Mahr, MarCal 16EWRi) were used to record the proximal to distal cartilaginous articular surface length and the proximal to distal extent (zone) of MPFL patellar insertion. The ratio of the patellar articular cartilage length covered by the zone of MPFL patellar insertion was calculated. The center-point of the zone of MPFL patellar insertion was also recorded as a percentile distance from the superior margin of the articular cartilage of the patella. These measures were analyzed by age and Spearman’s Correlation coefficients were calculated. Results: Both patellar articular cartilage length (p<0.001, rs 0.803) and zone of MPFL patellar insertion (p<0.001, rs 0.691) increased with age. The zone of MPFL patellar insertion averaged 8.34 mm in specimens <6 mos.; 11.73 mm in specimens ages 1-4 years; and 16.03 mm in specimens ages 5-11 years. The ratio of the patellar articular cartilage length covered by the zone of MPFL patellar insertion had a significant reduction with age (p=0.001, rs -0.499); decreasing from 66% and 55% in the two younger age groups, to 45% of the cartilage length with MPFL patellar insertion coverage in the school-age 5-11 year-old specimens. The center-point of the MPFL patellar insertion increased in distance from the superior pole of the articular cartilage of the patella with age (p< 0 .05, rs 0.397); starting slightly above (39% and 46%) and assuming a mid-pole (49%) position along the articular cartilage length in the school-age 5-11 year-old specimens (Figure 1B). Conclusion: In pre-ambulatory and early childhood years, the MPFL inserts on a large portion of the medial border of the patella, covering a distance >50% of the articular surface length and centered above the mid-point of the articular cartilage. During maturation, the length of the articular cartilage of the patella increases at a rate greater than the MPFL, resulting in an MPFL insertion averaging 45% the length of the articular surface and centered near the center-point of the articular cartilage (mean = 49th percentile from the superior border) in school age, pre-adolescents. Significance: Knowledge of the MPFL position relative to the articular cartilage length in children may add to understanding of the development of patellar instability, and aid in the accurate reconstruction of the ligament during treatment. [Figure: see text][Figure: see text]

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MICROENVIRONMENTAL INFLUENCES ON ARTICULAR CHONDROCYTE DIFFERENTIATION

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967120s00231 ◽

2020 ◽

Vol 8 (4_suppl3) ◽

pp. 2325967120S0023

Author(s):

Michael Chau ◽

Ferenc Toth ◽

Ameya Bendre ◽

Alexandra Armstrong ◽

Jeffrey Macalena ◽

...

Keyword(s):

Articular Cartilage ◽

Growth Plate ◽

Endochondral Ossification ◽

Articular Surface ◽

Surface Growth ◽

Articular Chondrocyte ◽

Medial Condyle ◽

Text Figure ◽

Biomechanical Stimuli

Background: Immature articular cartilage (a.k.a. articular epiphyseal cartilage complex, AECC), serves dual functions as an articulating layer and surface growth plate. The AECC originates from an uninterrupted cartilaginous template during embryogenesis, presumably stemming from the same pool of progenitors, but it is unclear how the articulating layer is maintained throughout life, while the surface growth plate undergoes endochondral ossification. Hypothesis: The function and fate of chondrocytes in the AECC are not predetermined in the embryo, but instead can be influenced during development by biochemical and/or biomechanical stimuli in the cellular microenvironment. Methods: Microenvironments of the articulating layer and surface growth plate were switched in an in vivo goat model. Twelve 3-week-old goats were used. Osteochondral autografts were harvested from medial and lateral condyles and trochlea of the distal femur. Subchondral bone was removed (Figures 1A and 1B). Grafts were inverted and press-fit into select sites, which were full (condyles) or low (trochlea) weightbearing (Figures 1C through 1E). Animals were allowed ambulation and range of motion as tolerated. Two goats each were euthanized at 1, 2, 3, 6, 12, and 24 weeks postoperatively. Distal femurs were harvested and grafts were analyzed with trichrome staining and in situ hybridization for Col10, Col2, and Prg4. Results: All animals survived surgery, ambulated within 24 hours, and none exhibited signs of surgical site infection. Macroscopically, grafts at the trochlea and lateral condyle maintained a more cartilaginous appearance than those at the medial condyle, but all eventually developed an osseous appearance. Histologically, there was healing over time, with early grafts often containing areas of hemorrhage and occasionally necrosis, followed by formation of granulation tissue and subjacent myelofibrosis, with eventual invasion and ossification. At later timepoints, there was better graft incorporation at the articular surface without replacement by fibrosis at the medial condyle (Figure 2). In situ hybridization demonstrated some Prg4 positive cells and a decrease in Col10 expression at the articular surface (Figure 3). Conclusions: The synovial microenvironment may play a protective role against endochondral ossification. Some incorporation of epiphyseal cartilage into articular cartilage occurred at sites subjected to both compressive and shear forces. Data suggest the existence of local cytokines and/or matrix effects on chondrocytes that stimulate different cell functions and fates. A limitation of this study is its observational nature. Further understanding of articular chondrocyte differentiation and identification of key biochemical and/or biomechanical stimuli hold therapeutic promise for articular cartilage regeneration, repair, and replacement. [Figure: see text][Figure: see text][Figure: see text]

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Perceptions of Stuttering of Different Age Groups

Perspectives of the ASHA Special Interest Groups ◽

10.1044/2019_pers-sig4-2018-0007 ◽

2019 ◽

Vol 4 (6) ◽

pp. 1311-1315

Author(s):

Sergey M. Kondrashov ◽

John A. Tetnowski

Keyword(s):

Age Groups ◽

School Age Children ◽

Clinical Implications ◽

School Age ◽

Fourth Edition ◽

Self Perception ◽

Behavioral Measures ◽

Self Rating ◽

Comparison Results ◽

Subject Pool

Purpose The purpose of this study was to assess the perceptions of stuttering of school-age children who stutter and those of adults who stutter through the use of the same tools that could be commonly used by clinicians. Method Twenty-three participants across various ages and stuttering severity were administered both the Stuttering Severity Instrument–Fourth Edition (SSI-4; Riley, 2009 ) and the Wright & Ayre Stuttering Self-Rating Profile ( Wright & Ayre, 2000 ). Comparisons were made between severity of behavioral measures of stuttering made by the SSI-4 and by age (child/adult). Results Significant differences were obtained for the age comparison but not for the severity comparison. Results are explained in terms of the correlation between severity equivalents of the SSI-4 and the Wright & Ayre Stuttering Self-Rating Profile scores, with clinical implications justifying multi-aspect assessment. Conclusions Clinical implications indicate that self-perception and impact of stuttering must not be assumed and should be evaluated for individual participants. Research implications include further study with a larger subject pool and various levels of stuttering severity.

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Anatomy of the Intermetatarsal Facets of the Fourth and Fifth Metatarsals

Foot & Ankle Orthopaedics ◽

10.1177/2473011420975709 ◽

2021 ◽

Vol 6 (1) ◽

pp. 247301142097570

Author(s):

Mossub Qatu ◽

George Borrelli ◽

Christopher Traynor ◽

Joseph Weistroffer ◽

James Jastifer

Keyword(s):

Articular Cartilage ◽

Digital Imaging ◽

Articular Surface ◽

Implant Design ◽

Joint Surface ◽

Fracture Classification ◽

Articular Damage ◽

Metatarsal Fracture ◽

Metatarsal Fractures ◽

The Mean

Background: The intermetatarsal joint between the fourth and fifth metatarsals (4-5 IM) is important in defining fifth metatarsal fractures. The purpose of the current study was to quantify this joint in order to determine the mean cartilage area, the percentage of the articulation that is cartilage, and to give the clinician data to help understand the joint anatomy as it relates to fifth metatarsal fracture classification. Methods: Twenty cadaver 4-5 IM joints were dissected. Digital images were taken and the articular cartilage was quantified by calibrated digital imaging software. Results: For the lateral fourth proximal intermetatarsal articulation, the mean area of articulation was 188 ± 49 mm2, with 49% of the area composed of articular cartilage. The shape of the articular cartilage had 3 variations: triangular, oval, and square. A triangular variant was the most common (80%, 16 of 20 specimens). For the medial fifth proximal intermetatarsal articulation, the mean area of articulation was 143 ± 30 mm2, with 48% of the joint surface being composed of articular cartilage. The shape of the articular surface was oval or triangular. An oval variant was the most common (75%, 15 of 20 specimens). Conclusion: This study supports the notion that the 4-5 IM joint is not completely articular and has both fibrous and cartilaginous components. Clinical Relevance: The clinical significance of this study is that it quantifies the articular surface area and shape. This information may be useful in understanding fifth metatarsal fracture extension into the articular surface and to inform implant design and also help guide surgeons intraoperatively in order to minimize articular damage.

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A Review of the Collagen Orientation in the Articular Cartilage

Cartilage ◽

10.1177/1947603520988770 ◽

2021 ◽

pp. 194760352098877

Author(s):

Roy D. Bloebaum ◽

Andrew S. Wilson ◽

William N. Martin

Keyword(s):

Surface Layer ◽

Articular Cartilage ◽

Fiber Orientation ◽

Collagen Fiber ◽

Articular Surface ◽

Imaging Techniques ◽

Collagen Fibers ◽

Deep Zone ◽

Collagen Fiber Orientation ◽

Critical Point Drying

Objective There has been a debate as to the alignment of the collagen fibers. Using a hand lens, Sir William Hunter demonstrated that the collagen fibers ran perpendicular and later aspects were supported by Benninghoff. Despite these 2 historical studies, modern technology has conflicting data on the collagen alignment. Design Ten mature New Zealand rabbits were used to obtain 40 condyle specimens. The specimens were passed through ascending grades of alcohol, subjected to critical point drying (CPD), and viewed in the scanning electron microscope. Specimens revealed splits from the dehydration process. When observing the fibers exposed within the opening of the splits, parallel fibers were observed to run in a radial direction, normal to the surface of the articular cartilage, radiating from the deep zone and arcading as they approach the surface layer. After these observations, the same samples were mechanically fractured and damaged by scalpel. Results The splits in the articular surface created deep fissures, exposing parallel bundles of collagen fibers, radiating from the deep zone and arcading as they approach the surface layer. On higher magnification, individual fibers were observed to run parallel to one another, traversing radially toward the surface of the articular cartilage and arcading. Mechanical fracturing and scalpel damage induced on the same specimens with the splits showed randomly oriented fibers. Conclusion Collagen fiber orientation corroborates aspects of Hunter’s findings and compliments Benninghoff. Investigators must be aware of the limits of their processing and imaging techniques in order to interpret collagen fiber orientation in cartilage.

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On the Natural Lubrication of Synovial Joints: Normal and Degenerate

Journal of Lubrication Technology ◽

10.1115/1.3453003 ◽

1977 ◽

Vol 99 (2) ◽

pp. 163-172 ◽

Cited By ~ 28

Author(s):

Joseph M. Mansour ◽

Van C. Mow

Keyword(s):

Articular Cartilage ◽

Solid Phase ◽

Articular Surface ◽

Moving Load ◽

Frictional Resistance ◽

Elastic Solid ◽

Surface Load ◽

Two Phase ◽

Tissue Properties ◽

Synovial Joints

Fluid flow and mass transport mechanisms associated with articular cartilage function are important biomechanical processes of normal and pathological synovial joints. A three-layer permeable, two-phase medium of an incompressible fluid and a linear elastic solid are used to model the flow and deformational behavior of articular cartilage. The frictional resistance of the relative motion of the fluid phase with respect to the solid phase is given by a linear diffusive dissipation term. The subchondral bony substrate is represented by an elastic solid. The three-layer model of articular cartilage is chosen because of the known histological, ultrastructural, and biomechanical variations of the tissue properties. The calculated flow field shows that for material properties of normal healthy articular cartilage the tissue creates a naturally lubricated surface. The movement of the interstitial fluid at the surface is circulatory in manner, being exuded in front and near the leading half of the moving surface load and imbibed behind and near the trailing half of the moving load. The flow fields of healthy tissues are capable of sustaining a film of fluid at the articular surface whereas pathological tissues cannot.

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PUBLIC HEALTH, NURSING AND MEDICAL SOCIAL WORK

PEDIATRICS ◽

10.1542/peds.5.3.569 ◽

1950 ◽

Vol 5 (3) ◽

pp. 569-573

Author(s):

EUNICE W. WILSON

Keyword(s):

Social Adjustment ◽

Physical Disability ◽

Age Groups ◽

Handicapped Child ◽

Training Methods ◽

School Age ◽

Parent Child Relationship ◽

Medical Social Work ◽

Child Relationship ◽

Health Nursing

The term "handicapped child" tends to put emphasis upon the handicap rather than the child. There is still undue emphasis in many types of physical disability upon how a specific handicap can be overcome by special education or training methods, without sufficient attention to whether the child is having the normal relationships and social experiences necessary to equip him later to compete in adult society. If the ultimate goal for the child who is handicapped is participation with nonhandicapped children in normal life situations, the total needs of the child, as well as those for his specific handicap, must be considered. This discussion portrays a method which individualizes a child and his needs in order to facilitate his social adjustment. Although the principles expressed have been drawn from experience with preschool children, they are applicable to some extent to all age groups. It is recognized, however, that problems arising in school age and adolescence may require different or additional types of service. The reaction of parents to knowledge of a child's handicap is of great significance in the child's adjustment. The following reactions seem fairly general: 1. The basic parent-child relationship is somewhat threatened and feelings about the child may undergo change.

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Reliability of Corneal, Epithelial, and Stromal Thickness Mapping for a 9-mm Zone Using Spectral-Domain Optical Coherence Tomography

Klinische Monatsblätter für Augenheilkunde ◽

10.1055/a-1535-1685 ◽

2021 ◽

Author(s):

Daniel Krause ◽

Niklas Mohr ◽

Mehdi Shajari ◽

Wolfgang J. Mayer ◽

Siegfried Priglinger ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Intraclass Correlation ◽

Age Groups ◽

Corneal Stroma ◽

Correlation Coefficients ◽

Spectral Domain ◽

Optical Coherence ◽

Noninvasive Technique ◽

Intraclass Correlation Coefficients ◽

Sd Oct

Abstract Purpose To evaluate the reliability of spectral-domain optical coherence tomography (SD-OCT; RTVue XR; Optovue, Inc., Fremont, CA, USA) for thickness mapping of the entire cornea (CT), corneal epithelium (ET). and corneal stroma (ST) over a 9-mm zone in healthy eyes. We sought to develop reference values for different age groups and elucidate potential sex- and age-dependent characteristics of corneal sublayer pachymetry maps. Methods Three consecutive SD-OCT scans were obtained in 166 healthy right eyes (mean age = 50 ± 20 years). The thickness maps contain 25 sectors over a 9-mm diameter zone. To test measurement reliability, intraclass correlation coefficients (ICC), coefficients of variation (CoV), and within-subject standard deviations (WSSD) were calculated. Results CT, ET, and ST ICCs ranged from 0.961 to 0.998, 0.896 to 0.945, and 0.955 to 0.998, respectively. CoV values for CT, ET, and ST ranged between 0.3 and 1.5%, 1.6 and 4.2%, and 0.4 and 1.7%, respectively. WSSD ranged from 6 to 41, 4 to 8, and 7 to 46 µm, respectively. A negative correlation was found between age and ET (p < 0.05) but not between age and ST or CT. No gender-related differences in CT, ET, or ST were detected. CoV of CT, ET, and ST measurements showed a positive correlation with age in 28, 64, and 28% of the sectors, respectively. Conclusion SD-OCT is a rapid and noninvasive technique that provides excellent reliability for corneal sublayer thickness measurements over a 9-mm zone. The reliability of the ET measurement seems to be negatively affected by age. Peripheral CT and global ET thin with age.

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Age-related changes in the composition and structure of human articular-cartilage proteoglycans

Biochemical Journal ◽

10.1042/bj1760683 ◽

1978 ◽

Vol 176 (3) ◽

pp. 683-693 ◽

Cited By ~ 127

Author(s):

M T Bayliss ◽

S Y Ali

Keyword(s):

Hyaluronic Acid ◽

Articular Cartilage ◽

Age Groups ◽

Human Articular Cartilage ◽

Human Cartilage ◽

Keratan Sulphate ◽

Age Related ◽

Composition And Structure ◽

Normal Human ◽

Cartilage Proteoglycans

1. Analysis of the purified proteoglycans extracted from normal human articular cartilage with 4M-guanidinium chloride showed that there was an age-related increase in their content of protein and keratan sulphate. 2. The hydrodynamic size of the dissociated proteoglycans also decreased with advancing age, but there was little change in the proportion that could aggregate. 3. Results suggested that some extracts of aged-human cartilage had an increased content of hyaluronic acid compared with specimens from younger patients. 4. Dissociated proteoglycans, from cartilage of all age groups, bind to hyaluronic acid and form aggregates in direct proportion to the hyaluronic acid concentration. 5. Electrophoretic heterogeneity of the dissociated proteoglycans was demonstrated on polyacrylamide/agarose gels. The number of proteoglycan species observed was also dependent on the age of the patient.

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On the relative role of different age groups during influenza A epidemics in Germany, 2002-2017

10.1101/147066 ◽

2017 ◽

Author(s):

Edward Goldstein

Keyword(s):

Influenza A ◽

Communicable Disease ◽

Age Groups ◽

School Age Children ◽

Relative Role ◽

School Age ◽

Limited Information ◽

School Students ◽

Using Data

AbstractBackgroundThere is limited information about the role of different age groups, particularly subgroups of school-age children and younger adults in propagating influenza epidemics.MethodsFor a communicable disease outbreak, some subpopulations may play a disproportionate role during the ascent of the outbreak due to increased susceptibility and/or contact rates. Such subpopulations can be identified by considering the proportion that cases in a subpopulation represent among all cases in the population occurring before the epidemic peak (Bp), the corresponding proportion after the epidemic peak (Ap), to calculate the relative risk for a subpopulation, RR=Bp/Ap. We estimated RR for several age groups using data on reported influenza A cases in Germany between 2002-2017.ResultsChildren aged 14-17y had the highest RR estimates for 7 out of 15 influenza A epidemics in the data, including the 2009 pandemic, and the large 2016/17, 2008/09, and 2006/07 seasons. Children aged 10-13y had the highest RR estimates during 3 epidemics, including the large 2014/15 and 2004/05 seasons. Children aged 6-9y had the highest RR estimates during two epidemics, including the large 2012/13 season. Children aged 2-5y had the highest RR estimate during the moderate 2015/16 season; adults aged 18-24y had the highest RR estimate during the small 2005/06 season; adults aged 25-34y had the highest RR estimate during the large, 2002/03 season.ConclusionsOur results support the prominent role of all school-age children, particularly the oldest ones, in propagating influenza epidemics in the community. We note that national vaccination coverage levels among older school-age children were lower than among younger school-age children during the recent influenza seasons in the US, and influenza vaccination program in England has not been phased in yet for secondary school students.

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Editorial - Vol 16: Number 2

Journal Biomedical and Biopharmaceutical Research ◽

10.19277/bbr.16.2.e ◽

2019 ◽

Vol 16 (2) ◽

pp. 152-153

Author(s):

Luis Monteiro Rodrigues

Keyword(s):

Age Groups ◽

Complete Characterization ◽

Normal Weight ◽

Overweight And Obesity ◽

School Age Children ◽

School Age ◽

Cross Sectional ◽

Similar Information ◽

Macaronesian Islands

The Nutrition and Food Sciences section includes two sequential papers regarding the anthropometric evaluation of pre-school and school age children from the Canarian Islands (Biomed & Biopharm Research, 2019;(16) 2; 154-164 DOI:10.19277/bbr.16.2.207) and from Azores (Biomed & Biopharm Research, 2019;(16) 2; 165-175 DOI:10.19277/bbr.16.2.208). These two cross-sectional studies focus the prevalence of normal weight, overweight, and obesity in those age groups, completing similar information published in the last issue of our journal in reference to the Madeiran Islands. A complete characterization of this condition is now achieved and described for the entire European Macaronesian islands, underlining the originality and interest of these papers.

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