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Ruptured Achilles tendons are significantly more degenerated than tendinopathic tendons.
No full textOBJECTIVE:
To ascertain whether there is an association between tendinopathic and ruptured Achilles tendons, hypothesizing that the histopathological aspects of tendinosis in tendinopathic tendons are less advanced than those found in ruptured Achilles tendons.
METHODS:
This was a comparative cohort study at a university teaching hospital. Histological examination was performed using hematoxylin and eosin and alcian blue/periodic acid-Schiff stained slides. The slides were interpreted using a semiquantitative grading scale assessing fiber structure, fiber arrangement, rounding of the nuclei, regional variations in cellularity, increased vascularity, decreased collagen stainability, hyalinization, and glycosaminoglycan. We calculated a pathology score giving up to three marks for each of the above variables, with 0 being normal and 3 being maximally abnormal. All the histology slides were assessed twice in a blinded manner, the agreement between two readings ranging from 0.170 to 0.750 (kappa statistics).
RESULTS:
We studied biopsy samples from the Achilles tendon of patients undergoing open repair for a subcutaneous rupture of their Achilles tendon (N = 35; average age (+/- SD), 48.4 +/- 16.9 yr; range, 26-80), biopsy specimens from the Achilles tendon of patients undergoing exploration for Achilles tendinopathy (N = 13; average age, 35.7 +/- 12.9 yr; range, 18-67) and specimens of Achilles tendons from individuals with no known tendon pathology (N = 16; average age, 65 +/- 19.1 yr; range, 46-82). The highest mean score of ruptured tendons was significantly greater than that of tendinopathic tendons (17.4 +/- 4.9 vs 10.5 +/- 6.1, P < 0.001), and highest mean score of tendinopathic tendons was greater that that of control tendons (10.5 +/- 6.1 vs 5.9 +/- 7.3) (P < 0.001).
CONCLUSION:
Ruptured and tendinopathic tendons are histologically significantly more degenerated than control tendons. The general pattern of degeneration was common to the ruptured and tendinopathic tendons, but there was a statistically significant greater degree of degeneration in the ruptured tendons. It is therefore possible that there is a common, as yet unidentified, pathological mechanism that has acted on both of these tendon populations
Outcome of surgery for chronic Achilles tendinopathy. A critical review.
No full textAchilles tendinopathy is often treated surgically after failure of nonoperative management, but results are not uniformly excellent. We critically assessed the methods of 26 studies that reported surgical outcomes of patients with this condition. Using 10 previously published criteria, and blinded to study outcomes, we derived a "methodology score" (0 to 100) for each study. This score was highly reproducible (r = 0.99, P < 0.01). Scores were generally low concerning the type of study, subject selection process, and outcome measures, which indicates methods deficiency in the way the study was designed, performed, and analyzed. We found a negative correlation between reported success rate and overall methods scores (r = -0.53, P < 0.01), and a positive correlation between year of publication and overall methods score (r = 0.70, P < 0.01). Study methods may influence reported surgical outcome, and we suggest guidelines for improving study design in this area of clinical research. We acknowledge that study methods have improved over the course of the past 20 years
Early weightbearing and ankle mobilization after open repair of acute midsubstance tears of the achilles tendon.
No full textPURPOSE:
To study the effects of early weightbearing and ankle mobilization after acute repair of ruptured Achilles tendon.
STUDY DESIGN:
Comparative longitudinal study.
METHODS:
Patients in group 1 were postoperatively immobilized with their ankle in gravity equinus, they were encouraged to bear weight on the operated limb as soon as possible to full weightbearing, and they received a single cast change at 2 weeks, with the ankle accommodated in an anterior splint in a plantigrade position, allowing the ankle to be plantar flexed fully but not dorsiflexed above neutral. Patients in group 2 were immobilized with their ankle in full equinus with a cast change at 2 weeks, when the ankle was immobilized in mid equinus, and at 4 weeks, when the ankle was immobilized in a plantigrade position, and they were advised to bear weight.
RESULTS:
Patients in group 1 attended fewer outpatient visits, completely discarded their crutches at an average of 2.5 weeks, and more were satisfied with the results of surgery. At ultrasonography, the average thickness of the repaired tendon was 12.1 mm, with no difference in the thickness of the ruptured tendon regardless of postoperative management. There was no significant difference in isometric strength between the two groups.
CONCLUSIONS:
Early weightbearing with the ankle plantigrade is not detrimental to the outcome of repair after acute rupture of the Achilles tendon and shortens the time needed for rehabilitation. However, strength deficit and muscle atrophy are not prevented
Long-term ultrasonographic features of the Achilles tendon after rupture.
No full textPURPOSE:
To assess the long-term ultrasonographic appearance of rupture of the Achilles tendon.
SUBJECTS AND METHODS:
We examined 70 patients at an average of 63 months (range 10-120 months) after rupture of the Achilles tendon. We assessed the patient's contralateral tendon and also performed ultrasonography on the Achilles tendon of 70 age- and sex-matched controls. We recorded the maximum transverse anteroposterior diameter, the presence of intratendinous alterations, and the presence of intratendinous calcification.
RESULTS:
The average maximum anteroposterior diameter of the ruptured tendon was 11.7 mm (SD = 2.10). The patients' normal tendons measured an average of 5.4 mm (SD = 0.9), and there was an average measure of 4.9 mm (SD = 0.5) (p = 0.0001) in the controls. There was no difference in the maximum anteroposterior diameter of the ruptured tendon depending on the method of treatment (conservative, open repair, percutaneous repair). Seventeen patients exhibited areas of hypoechogenicity in their ruptured tendon, two patients had areas of hypoechogenicity in their unruptured contralateral tendon, and 10 patients had calcification in their ruptured tendon.
CONCLUSION:
The anteroposterior diameter of the ruptured tendon was significantly greater than the nonruptured contralateral. However, when compared with a group of individually age- and sex-matched controls, the patients' contralateral tendons had significantly greater maximum anteroposterior diameter and had a greater prevalence of intratendinous alterations. This difference may represent a background of subclinical tendinopathy that may predispose to rupture
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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