Achilles tendon shape and echogenicity on ultrasound among active badminton players

Chronic adaptations of the long head of the biceps tendon and groove in professional baseball pitchers

BACKGROUND AND HYPOTHESIS

The long head of the biceps tendon (LHBT) plays a significant shoulder stabilizing role during pitching, with the large forces and repetitions involved in overhead throwing likely contributing to LHBT pathology. Determining whether the LHBT undergoes adaptive changes in baseball pitchers and how these changes relate to bicipital groove morphology can improve our understanding of the biceps function at the glenohumeral joint. Therefore, the purpose of this study was to determine the chronic adaptations of the bicipital groove morphology and the LHBT in professional baseball pitchers, with a secondary purpose of evaluating biceps integrity as it relates to torsional changes of the bicipital groove. We hypothesized that the throwing arm of professional baseball pitchers would exhibit chronic adaptations of the LHBT compared with their nonthrowing arm, and that these adaptations would be related to the bicipital groove morphology.

MATERIALS AND METHODS

Fifty-three professional baseball pitchers were enrolled at the beginning of the 2015 Major League Baseball spring training. Ultrasound was used to bilaterally measure humeral retroversion and to capture images of the bicipital groove and the LHBT. MATLAB software was used to calculate the area of the bicipital groove, and ImageJ software was used to quantify the area, echogenicity, and circularity of the LHBT.

RESULTS

The dominant arm LHBT cross-sectional area was significantly smaller than the nondominant arm (9 mm² vs. 10 mm²; P = .011), whereas the dominant arm LHBT echogenicity was significantly higher than the nondominant arm (65 optical density vs. 59 optical density; P = .002). Pitchers with more bicipital groove rotational adaptation (more retroversion) had significantly more LHBT echogenicity adaptation compared with pitchers with less bicipital groove rotational adaptation (12 vs. 2; P = .023).

CONCLUSION

There are significant bilateral differences in the LHBT of professional baseball pitchers. An adaptation in bony rotation was associated with a larger bilateral difference in LHBT echogenicity but was not related to bilateral differences in LHBT area or circularity. Therefore, the bilateral difference in echogenicity is impacted by bony morphology, whereas the bilateral difference in cross-sectional area may be independent of bony morphology in this healthy population.

Identifying achilles tendon structure differences by ultrasound tissue characterization in asymptomatic individuals

Ultrasound Tissue Characterization (UTC) is a modality that can be utilized to characterize tendon tissue structure using ultrasonographic imaging paired with a computer algorithm to distinguish echo-types. Several studies have demonstrated UTCs ability to distinguish Achilles tendon morphology changes, but no study has established normative data of the Achilles tendon in the general population. The aim of this study was to determine UTC echo-type distribution in the Achilles tendon in an asymptomatic population. UTC scans were completed and analyzed on 508 participants without Achilles tendinopathy. Dedicated UTC-algorithms were used to distinguish and calculate echo-type percentages and the fiber type distribution was compared. The overall sample echo-type percentages demonstrated greater levels of Type I and II echo-types, 65.73% and 32.00%, respectively, and lower levels of Type III and IV echo-types, 1.74% and 0.57%, respectively. In addition, females had lower levels of Echo-type I compared to men and greater levels of echo-type II (p < 0.001). We also found that African-Americans had significantly greater amounts of echo-type I and lesser amounts of echo-type II when compared to Caucasians (p < 0.05). The results of this study create a normative data set for future UTC studies to utilize as a baseline for the evaluation of Achilles tendons. In addition, it demonstrated tendon type differences between sexes and races that need to be accounted for in future studies.

Assessing the Reliability of Echo Intensity of Craniovertebral Muscle Group using B-Mode Ultrasound: A Technical Note

An acceptable reliability is needed for each scale and a valid decision-making process. Ultrasonography is a simple, cost-effective, and accessible tool compared to magnetic resonance imaging (MRI) to assess echo intensity (EI) as a biomarker of muscle function in neck musculoskeletal problems. However, no evidence is available regarding the reliability of neck muscle echogenicity according to rehabilitative ultrasonography in clinical studies on forward head posture (FHP). We determined the reliability of neck muscles EI in individuals with and without FHP. Transverse images of deep neck flexors (Longus Coli) and suboccipital (Rectus capitis posterior minor) muscles were acquired from 20 individuals with FHP and 20 controls in one session. The intraclass correlation coefficient (ICC), minimum detectable change (MDC), and standard error of measurement (SEM) for EI were measured in this study. The ICC, SEM, and MDC ranges were 0.50 - 0.51, 2.73 - 3.41, and 7.56 - 9.46 for the Longus colli muscle and 0.48 - 0.49, 3.29 - 4.98, and 9.13 - 13.81 for the rectus capitis posterior minor (RCPm) muscle, respectively. Based on the present findings, EI showed acceptable reliability; therefore, it can be used for assessment of neck muscle morphology.

Exercise Progression to Incrementally Load the Achilles Tendon

PURPOSE

The purposes of our study were to evaluate Achilles tendon loading profiles of various exercises and to develop guidelines to incrementally increase the rate and magnitude of Achilles tendon loading during rehabilitation.

METHODS

Eight healthy young adults completed a battery of rehabilitation exercises. During each exercise, we collected three-dimensional motion capture and ground reaction force data to estimate Achilles tendon loading biomechanics. Using these loading estimates, we developed an exercise progression that incrementally increases Achilles tendon loading based on the magnitude, duration, and rate of tendon loading.

RESULTS

We found that Achilles tendon loading could be incrementally increased using a set of either isolated ankle movements or multijoint movements. Peak Achilles tendon loads varied more than 12-fold, from 0.5 bodyweights during a seated heel raise to 7.3 bodyweights during a forward single-leg hop. Asymmetric stepping movements like lunges, step ups, and step downs provide additional flexibility for prescribing tendon loading on a side-specific manner.

CONCLUSION

By establishing progressions for Achilles tendon loading, rehabilitative care can be tailored to address the specific needs of each patient. Our comprehensive data set also provides clinicians and researchers guidelines on how to alter magnitude, duration, and rate of loading to design new exercises and exercise progressions based on the clinical need.

Ultrasound imaging evaluation of structural and textural features in asymptomatic achilles tendons in pre-professional dancers: A cross-sectional study

OBJECTIVE

To evaluate performance descriptors, sociodemographics variables and tendon echogenicity of asymptomatic Achilles tendons and to compare the echotexture from different classification subgroups.

DESIGN

A prospective, randomized cross-sectional study was carried out.

SETTING

laboratory of university.

PARTICIPANTS

Forty-two Achilles tendons (AT) were recruited from pre-professional dancers. Based on the echogenicity pattern, the sample was divided into two groups (n = 21, Heterogeneous group; n = 21, Homogeneous group).

MAIN OUTOCOME MEASURES

Ultrasound images and ImageJ measurements were performed to evaluate thickness (AT-TH), echointensity (EI) and echovariation (EV), in addition to a balance and endurance test were measured as performance parameter.

RESULTS

EI (p = 0.001) and EV (p = 0.001) reported statistically significant differences between groups. AT-TH, endurance test, balance test, years of dance, training hours per week and average pointe hours per week did not showed differences between groups. A multivariate prediction model between groups and the echotexture variables (EI (R² = 0.569; EV (R² = 0.341)) were determined.

CONCLUSION

Asymptomatic AT of heterogeneous group showed a lower EI and a higher EV compared to homogeneous group. Tendon echogenicity did not interact with performance variables.

Ultrasound imaging features of the Achilles tendon in dancers. Is there a correlation between the imaging and clinical findings? A cross-sectional study

OBJECTIVES

To analyze the prevalence of tendon pathology and performance associated in pre-professional classic dancers with no history of Achilles tendon (AT) pain.

DESIGN

A cross-sectional study was conducted.

PARTICIPANTS

Twenty-nine classic ballet dancers without AT pain (58 tendons) were recruited. The tendons were classified (normal, abnormal) using ultrasound imaging (USI). Cross-sectional area (CSA) and thickness of flexor hallucis longus (FHL) muscle were measured using USI. Range of movement (ROM) of the first metatarsophalangeal join, balance test, endurance test and vertical jump were measured (bilaterally) as performance variables.

RESULTS

More than a half (62%) of the participants had at least one abnormal tendon, with 45% of the dancers in the abnormal group having bilateral abnormalities. Dancers with AT pathology had significantly more years of dancing and number of weekly pointe hours than those with no pathology on US imaging. No significant differences between the groups were identified for the rest of the variables. Dancing years were moderately correlated with AT thickness.

CONCLUSIONS

Asymptomatic classic dancers had a high incidence of tendon pathology. Increased dancing years was associated with pathology in the AT. Nevertheless, these abnormalities may not affect dance performance.

Myotendinous asymmetries derived from the prolonged practice of badminton in professional players

Background

The continued practice of a sport linked to the unilateral predominance of the dominant side can provoke chronic asymmetric adaptations in the myotendinous structure and mechanical properties. Objectives: The main purpose was to determine whether asymmetry between the preferred and non-preferred lower limb is present in the lower limb tendon structure, muscle architecture and stiffness values of professional badminton players.

Methods

Sixteen male professional badminton players (age = 24.1 ± 6.7 years; body height = 177.90 ± 7.53 cm) participated in this study. The muscle architecture of the vastus lateralis (VL), medial gastrocnemius (MG) and lateral gastrocnemius (LG) and the structure of patellar and Achilles tendons were measured in the dominant and non-dominant lower limb with ultrasonography. Stiffness was also measured at the same points with a hand-held MyotonPro. Significant differences between the dominant and non-dominant lower limb were determined using Student’s t test for related samples.

Results

Bilateral differences were observed for thickness, width and cross-sectional area (CSA) in both tendons showing higher values for the dominant side: patellar tendon CSA (2.02 ± 0.64 vs. 1.51 ± 0.42 cm²; p < 0.05) and Achilles tendon CSA (1.12 ± 0.18 vs. 0.92 ± 0.28 cm²; p < 0.05). No significant differences were observed in muscle architecture and myotonic variables between the dominant and non-dominant lower limb.

Conclusions

The prolonged practice of badminton caused asymmetries in the CSA, width and thickness of the patellar and Achilles tendon between the dominant and non-dominant lower limbs. No bilateral differences were found in the muscle architecture of VL, MG and LG or in the stiffness of any muscle or tendon analyzed.

Lower Limb Dominance, Morphology, and Sonographic Abnormalities of the Patellar Tendon in Elite Basketball Players: A Cross-Sectional Study

CONTEXT

Patellar tendinopathy is common in basketball players, and structural ultrasound abnormalities can be found in symptomatic and asymptomatic tendons. Lower limb dominance may also be a critical load factor, potentially leading to overloading of the patellar tendon.

OBJECTIVE

To describe and compare the prevalence by lower limb dominance of patellar tendons with structural and vascular abnormalities and to describe the morphologic measures of tendons without abnormalities among adult male elite basketball players.

DESIGN

Cross-sectional study.

SETTING

Medical center of a professional basketball team in the Spanish league.

PATIENTS OR OTHER PARTICIPANTS

A total of 73 adult male elite basketball players (146 patellar tendons; age = 26.8 ± 4.9 years, height = 198.0 ± 0.1 cm, mass = 95.4 ± 11.4 kg).

MAIN OUTCOME MEASURE(S)

We used ultrasound to screen the patellar tendons for the presence of structural and vascular abnormalities. Tendons were categorized as abnormal if they demonstrated a focal area of hypoechogenicity, thickening, or neovascularization. We also examined the cross-sectional area and thickness of tendons without abnormalities. Prevalence and morphologic measures were compared by limb dominance.

RESULTS

A total of 35 players (48%) had bilateral abnormalities, whereas 21 (28.7%) had unilateral abnormalities. Among the 91 abnormal tendons, 90 (61.6% of 146 tendons) exhibited a focal area of hypoechogenicity, 59 (40.4% of 146 tendons) exhibited thickening, and 14 (9.6% of 146 tendons) exhibited neovascularization. No group differences were detected between the dominant and nondominant limbs. Among the 55 normal patellar tendons, 34 were bilateral (from 17 players) and 21 were unilateral. Approximately 25% (n = 14) of all 55 normal tendons had a cross-sectional area that was greater than 182.8 mm² and a thickness greater than 7.2 mm. Among the 34 bilateral normal tendons, no group differences were observed between the dominant and nondominant limbs for either cross-sectional area or thickness.

CONCLUSIONS

The prevalence of abnormal tendons was high among adult male elite basketball players, and bilateral presentations were more frequent. Structural abnormalities were most common.

Quantitative Ultrasound Elastography With an Acoustic Coupler for Achilles Tendon Elasticity: Measurement Repeatability and Normative Values

OBJECTIVES

The purposes of this study were to measure intraobserver and interobserver repeatability of quantitative elastography using an acoustic coupler for the Achilles tendon, to compare elastographic values among different age groups, and to assess the correlation between quantitative and conventional qualitative measurements.

METHODS

One hundred asymptomatic Achilles tendons of 50 volunteers were examined. For quantitative elastography, the strain value of the tendon was divided by that of the acoustic coupler with a known Young modulus, and the strain ratio was calculated. B-mode image assessment and qualitative elastography were also performed. Intraobserver repeatability and interobserver repeatability of strain ratio measurements were calculated. The strain ratios were compared among age groups by the Kruskal-Wallis test. Additionally, strain ratios for each B-mode grade and qualitative elastographic grade were compared by the Wilcoxon signed rank test.

RESULTS

Intraobserver repeatability intraclass correlation coefficient (1, 3) values were 0.87 and 0.93, respectively. The correlation coefficient between the observers' measurements was 0.61. The strain ratio for the 30s age group was 0.27, which was significantly lower than the values for the other age groups (P < .001). Although 97 of 100 tendons were normal on B-mode evaluations, 36 of the 97 tendons were degenerated on qualitative elastography and also had higher strain ratio values than normal tendons.

CONCLUSIONS

Quantitative elastography using an acoustic coupler is a reproducible technique for measuring the elasticity of the Achilles tendon. It may detect early tendon degeneration that is not depicted on B-mode imaging.

Tendinopathy: Is Imaging Telling Us the Entire Story?

Synopsis Tendinopathy is frequently associated with structural disorganization within the tendon. As such, the clinical use of ultrasound and magnetic resonance imaging for tendinopathy has been the focus of numerous academic studies and clinical discussions. However, similar to other musculoskeletal conditions (osteoarthritis and intervertebral disc degeneration), there is no direct link between tendon structural disorganization and clinical symptoms, with findings on imaging potentially creating a confusing clinical picture. While imaging shows the presence and extent of structural changes within the tendon, the clinical interpretation of the images requires context in regard to the features of pain and the aggravating loads. This review will critically evaluate studies that have investigated the accuracy and sensitivity of imaging in the detection of clinical tendinopathy and the methodological issues associated with these studies (subject selection, lack of a robust gold standard, reliance on subjective measures). The advent of new imaging modalities allowing for the quantification of tendon structure or mechanical properties has allowed new critical insight into tendon pathology. A strength of these novel modalities is the ability to quantify properties of the tendon. Research utilizing ultrasound tissue characterization and sonoelastography will be discussed. This narrative review will also attempt to synthesize current research on whether imaging can predict the onset of pain or clinical outcome, the role of monitoring tendon structure during rehabilitation (ie, does tendon structure need to improve to get a positive clinical outcome?), and future directions for research, and to propose the clinical role of imaging in tendinopathy. J Orthop Sports Phys Ther 2015;45(11):842-852. Epub 21 Sep 2015. doi:10.2519/jospt.2015.5880.