scholarly journals In vivo stiffness assessment of patellar and quadriceps tendons by strain ultrasound elastography

2021 ◽  
pp. 1-10
Author(s):  
Surangika Wadugodapitiya ◽  
Makoto Sakamoto ◽  
Sayaka Suzuki ◽  
Yusuke Morise ◽  
Koichi Kobayashi

BACKGROUND: The patellar and quadriceps tendons are responsible for the extension mechanism of the knee joint and frequently become inflamed during sports. Diagnosis and determination of when an athlete can return to sports following these injuries are usually performed by assessing morphological features and functional outcomes. Nevertheless, mechanical properties are not being assessed. OBJECTIVE: To describe the stiffness characteristics of these two tendons over the range of knee flexion and to test the feasibility of using strain ultrasound elastography (SE). METHODS: SE with an acoustic coupler as the reference was performed for nine healthy males. Relative stiffness measurements were obtained using the strain ratio (SR = target tissue strain/reference strain) by placing the knee in five different flexion angles. Lower SR indicates higher relative stiffness. RESULTS: This study showed reliable measurement with good intra- and inter-rater agreement for SR at 30°. SR of the quadriceps tendon decreases as knee flexion increases, indicating increased relative stiffness. In the patellar tendon, no significant difference was observed between 30° and 60°. Beyond 60°, relative stiffness increased constantly. CONCLUSIONS: SE is a reproducible and feasible tool to monitor relative stiffness of the patellar and quadriceps tendons in routine clinical settings.

2020 ◽  
Vol 93 (1110) ◽  
pp. 20200035
Author(s):  
Doaa M Emara ◽  
Nagy N. Naguib ◽  
Mohamed Yehia ◽  
Mohamed M. El Shafei

Objective: Ultrasound elastography is increasingly used in the diagnosis of prostate cancer, however results are heterogeneous. We correlate in a large sample-size prospective study the accuracy of elastography, aiming to settle an accurate cut-off point for diagnosis and possibility of use as a screening tool. Methods: Prospective study that included 120 patients with mean age 59.5 ± 9.8 years, showing enlarged prostate by clinical examination with prostate-specific antigen >4 ng ml−1. The study was done using high frequency high resolution endorectal probe with real time tissue elastography. Grayscale ultrasound examination was done first with Doppler followed by elastography color-coded map and strain ratio measurement. Then, transrectal ultrasound-guided core biopsy was done from suspicious areas detected by elastography (totally or partly stiff by color-coded map or with relative increased strain ratio), besides standard six-quadrant core biopsy samples. Results: There was statistically significant difference (p < 0.001) regarding strain ratio in benign and malignant lesions. Strain ratio showed significant proportionate correlation with prostate-specific antigen level and Gleason pathological score, while no significant correlation noted with the age or the prostatic volume. A strain ratio with a cut-off value of 1.9 showed a sensitivity of 100%, specificity 93.8%, positive predictive value of 79.3%, negative predictive value 100 and 95% accuracy in differentiating between malignant and benign lesions. Conclusion: Strain ratio improves the detection of prostatic cancer with high sensitivity (100%) and high negative predictive value (100%). Advances in knowledge: Different prostatic lesions are mostly similar in grayscale ultrasound. Imaging plays an important role in differentiation of prostatic nodules. Ultrasound elastography may play an important role in distinguishing benign from malignant nodules.


2011 ◽  
Vol 11 (05) ◽  
pp. 1025-1043 ◽  
Author(s):  
J. H. MÜLLER ◽  
C. SCHEFFER ◽  
A. ELVIN ◽  
P. J. ERASMUS ◽  
E. M. DILLON

Musculoskeletal modeling has found wide application in joint biomechanics investigations. This technique has been improved by incorporating subject-specific skeletal elements and passive patellofemoral stabilizers in a dynamic analysis. After trochlear engagement, the volunteers' patellae displaced laterally, whereas tilt was subject specific. Comparison of the tilt and mediolateral position values to in vivo MRI values at 30° knee flexion showed a mean accuracy of 84.4% and 96.9%, respectively. Medial patellofemoral ligament tension decreased with knee flexion, while the patellar tendon–quadriceps tendon ratio ranged from 0.4 to 1.2. The patellofemoral contact load–quadriceps tendon load ratio ranged from 0.7 to 1.3, whereas the mediolateral load component–resultant load ratio ranged from 0 to 0.4. Three validated subject-specific musculoskeletal models facilitated the analysis of patellofemoral biomechanics: Subject-specific patella tracking and passive stabilizer response was analyzed as a function of dynamic knee flexion.


2016 ◽  
Vol 18 (3) ◽  
pp. 299 ◽  
Author(s):  
Ayse Nur Sirin Ozcan ◽  
Sinan Tan ◽  
Nuray Gulden Tangal ◽  
Saliha Cıracı ◽  
Savas Kudas ◽  
...  

Aims: The comparison of elastographic features of quadriceps and patellar tendons in a group of professional athletes and healthy volunteers and the description of elasticity characteristics of these tendons. Material and methods: Thirtynine professional athletes (22 male, 17 female; mean age 18.5 years) and 35 healthy volunteers (21 male, 14 female; mean age 19 years) were included. They were divided into two groups by gender. Quadriceps tendon, patellar side of the patellar tendon, and tibial side of the patellar tendon elasticity patterns and strain ratios were investigated with real-time ultrasound elastography. The elasticity features of the dominant leg and non-dominant leg of athletes and volunteers legs were compared. In addition quadriceps and patellar tendons were compared separately for three distinct tendon locations. Results: There was no difference between the athletes and the healthy volunteers and also between the dominant leg and non-dominant leg of athletes. At tendon comparison, the quadriceps tendon was harder than the patellar tendon at both side and patellar side of patellar tendon was found to be stiffer than the tibial side of patellar tendon. Conclusions: Although biomechanical studies showed that tendon stiffness increased after long exercise, no significant difference was found between athletes’ and healthy volunteers’ tendon elasticity. These three tendon locations exhibit different elasticity features and the knowledge of the elasticity feature will be useful in assessing tendon pathologies.


2019 ◽  
Vol 7 (3_suppl) ◽  
pp. 2325967119S0002
Author(s):  
Katherine Rizzone ◽  
Grace E. Weyand ◽  
Michael S. Richards ◽  
Catherine K. Kuo ◽  
Mark R. Buckley

Background Osgood-Schlatter Disease (OSD) impacts millions of young athletes every year, yet its biomechanical etiology remains unclear. It’s been postulated that increased growth velocity in children elevates tension within the patellar tendon, placing distal strain on the tibial tubercle, causing anterior knee pain, but this process has not been previously elucidated. The purpose of this study was to evaluate axial tensile and transverse compressive strains in adolescent patellar tendons during exercise to identify differences between those with and without OSD using a cumulative strain, ultrasound elastography measurement method [REF: Chimenti et al 2016]. Methods Axial tensile and transverse compressive strains of the patellar tendon in eight adolescents with OSD and ten adolescents without OSD were quantified from ultrasound elastography images. Multiaxial strains of the patellar tendon were assessed as the participant performed two different exercises: 1) participant seated with leg fully extended, participant bends knee, followed by a return to initial extended position; (2) participant standing performs a squat and then returns to initial standing position. Participants’ disease severity was clinically assessed using the VISA-P and Cincinnati knee scale. Results Mean age was 13.1 years (+/- 2.7), 39% were male (63% of OSD group). There was no statistically significant difference in patellar tendon tensile strains during the seated knee flexion and squat positions between groups (p = 0.99, p = 0.83 respectively). The OSD group had significantly less tendon compression compared to the non-OSD group during both the knee flexion (p <0.01), and squat exercises (p <0.05). Conclusions/Significance Adolescents with OSD had lower transverse compressive strains in the patellar tendon as compared to adolescents without OSD. In contrast, tensile strains were not increased in children with OSD. These findings appear to contradict the tension hypothesis postulating that OSD is caused by increased patellar tendon axial tension associated with rapid bone growth, Instead, impingement from the tibia leading to transverse tendon compression may lead to an adaptive stiffing the patellar tendon, However, further research is needed to confirm this hypothesis. While OSD is a common cause of knee pain in growing athletes that frequently leads to loss in participation, its etiology is unclear, making development of effective treatment approaches difficult. This study highlights differences in multiaxial patellar tendon strains in adolescents with OSD which may help direct future research on management strategies.


2018 ◽  
Vol 1 (1) ◽  
pp. 76 ◽  
Author(s):  
Özkan Özen ◽  
Murat Atabey Özer ◽  
Alptekin Tosun ◽  
Serkan Özen

Aim: To evaluate the strain ratio of the optic nerve and retina-choroid-sclera (RCS) layers in individuals with physiological optic disc cupping (PC) and glaucoma patients using strain elastography.Material and methods: We evaluated 56 eyes of 56 subjects (20 eyes with glaucoma, 19 eyes with PC, and 17 normal eyes). The strain ratio of orbital fat to optic nerve (SROFON) was calculated as the ratio of the optic nerve to intraconal fat tissue and the strain ratio of orbital fat to retina-choroid-sclera (SROFRCS) was calculated as the ratio of RCS layers to intraconal fat tissue.Results: SROFON was 0.92 in the control group, 1.07 in the PC group and 1.6 in the glaucoma group and a statistically significant difference was present between the three groups (p<0.05). SROFRCS had no statistically significant difference between the three groups.Conclusions: SROFON values could contribute to the differentiation of the patients with glaucoma and PC.


VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.


Author(s):  
Tamilarasi G P ◽  
Sabarees G

Oxidation is an essential reaction in the human body, which determines the expression of proteins in the body. This results in the altered expression like rapid growth resulting in cancers and other disorders. Many synthetic drugs are available in the market that is effective in limiting the free radical generation and the reaction of radicals with cells. Unfortunately, all those synthetic drugs were found to cause side effects and adverse effects in the body. But given the accuracy of the predictability of the results and administration, this research focuses on testing the anti-oxidant efficiency in rat models testing the biochemical parameters. Investigations have also been done on the anti-oxidant activity of Tectona, but every research was concentrated to prove the anti-oxidant activity only. extract had been tested for anti-oxidant activity by estimating various tissue parameters and it showed better activity. As predicted, there is a significant difference in the and results which can be explained are due to the physiological conditions that exist inside the body.


Author(s):  
Miriam del Carmen Carrasco-Portugal ◽  
Francisco Javier Flores-Murrieta

Pharmaceutical alternatives are products with the same active moiety, but different salt, ester or pharmaceutical form. Regulatory agencies have different criteria for this kind of drug. The European Medicines Agency (EMA) accepts the generic substitution using these alternatives, whereas the Food and Drug Administration (FDA) only authorizes generic substitution of pharmaceutical equivalents. The objective of this paper is to describe some relevant aspects that should be considered before deciding on making a generic substitution with pharmaceutical alternatives. It is important to note that a pharmaceutical alternative must show no significant difference in the rate and extent of absorption (bioequivalence) in a well-conducted in vivo study when compared with the reference formulation. Current Mexican regulations state that generic substitution is possible using pharmaceutical alternatives when bioequivalence is demonstrated in in vivo studies conducted under the NOM-177-SSA1-2013 criteria. In conclusion, generic substitution with pharmaceutical alternatives is possible if these products demonstrate in vivo bioequivalence when compared with the reference product.


2020 ◽  
Vol 10 (2) ◽  
pp. 133-148
Author(s):  
Ankaj Kaundal ◽  
Pravin Kumar ◽  
Rajendra Awasthi ◽  
Giriraj T. Kulkarni

Aim: The study was aimed to develop mucoadhesive buccal tablets using Aster ericoides leaves mucilage. Background : Mucilages are naturally occurring high-molecular-weight polyuronides, which have been extensively studied for their application in different pharmaceutical dosage forms. Objective: The objective of the present research was to establish the mucilage isolated from the leaves of Aster ericoides as an excipient for the formulation of the mucoadhesive buccal tablet. Method: The mucilage was isolated from the leaves of Aster ericoides by maceration, precipitated with acetone and characterized. Tablets were prepared using wet granulation technique and evaluated for various official tests. Results: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Conclusion: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Other: However, to prove the potency of the polymer, in vivo bioavailability studies in human volunteers are needed along with chronic toxicity studies in suitable animal models.


2017 ◽  
Vol 5 (2) ◽  
pp. 1
Author(s):  
Mulyati Mulyati ◽  
Suryati Suryati ◽  
Irfani Baga

The study aims to isolate, characterize, and examine probiotic bacteria's inhibitory ability against Vibrio harveyi bacteria, both in-vitro and in vivo. Methods used in the study consist of 1) An Isolation of Candidate Probiotic Bacteria, 2) An Antagonistic Test of Candidate Probiotic Bacteria in vitro, 3) An Identification of Bacteria, 4) A Pathogenicity Test of Candidate Probiotic Bacteria, 5) An Antagonistic Test of Candidate Probiotic Bacteria against V. harveyi in vivo. According to the isolation of candidate probiotic bacteria, there are 18 isolated candidate probiotic. After being tested for its inhibitory ability in vitro, there are 8 isolates with zone of inhibition as follows: isolate MM 7 from intestine (22 mm), isolate MM 6 from intestine (12 mm), isolate MM 10 from sea water (10 mm), isolate MM 5 from intestine (9 mm), isolate MM 4 from intestine (8 mm), isolate MM 3 from intestine (7 mm), isolate MM 2.2 from intestine (7 mm), isolate MM 2.1 from intestine (7 mm). Eight genera of the candidate probiotic bacteria is derived from Portunid crab, they are Staphylococcus, Streptococcus, bacillus, vibrio, Alcaligenes, Lactobacillus, micrococcus. Before proceeding the V. harveyi bacterial challenge test in vivo, three potential isolates consisting of MM6, MM7 and MM10 as the probiotic bacteria are pathogenicity-tested against V. harveyi. The survival rate of Portunid crab on pathogenicity test using MM6, MM7 and MM10 generates 91.11-100%, while the control generates 100% survival rate. Variance analysis result through post-hoc Tukey's Honest Significant Difference (HSD) test at 95% confidence interval indicates that isolate MM7 and MM10 are significantly able to increase hatchling Portunid crab's survival rate.


Sign in / Sign up

Export Citation Format

Share Document