The effect of swimming volume and intensity on changes in supraspinatus tendon thickness

Metrology of Supraspinatus Tendon Thickness in Swimmers with Tendinopathy Using Ultrasound Imaging: An Intra- and Inter-Rater Reliability Study

Objective: This study aimed to assess the relative and absolute intra- and inter-rater reliability of supraspinatus tendon (SST) thickness. Materials: Thirty adolescent swimmers with supraspinatus (SS) tendinopathy (n = 15) and a control-matched group (n = 15) were evaluated. Tendon thickness was measured according to four different measure procedures, i.e., (1) at 15 mm, (2) at 10, 20, and 30 mm, (3) at 10, 15, and 20 mm, and (4) 5 and 10 mm lateral to the most hyperechogenic reference point of the biceps tendon. Each examiner took two US images for the test measurements with a 10 min rest period. After 30 min, the subjects underwent retest measurements that were also repeated 1 week later. Results: SST thickness was greater in swimmers with SS tendinopathy compared with the matched control group for each procedure and rater (p < 0.001). Intra- and inter-rater reliability was good to excellent (ICC2.3: 0.78-0.98 and 0.83-0.97, respectively) in both groups. The lowest intra- and inter-rater reliability was found in procedures no. 2 and 4 (ICC2.3: 0.78 and 0.83). However, procedure no. 3 was the most reliable with the lowest error rate (ICC2.3: 0.92-0.97; SEM: 0.05-0.10 mm; MDC: 0.14-0.28 mm). Conclusions: The study confirmed the diagnostic value of ultrasound in SS tendinopathy. A multiple-reference-point procedure including a simple methodology (10, 15, and 20 mm from biceps tendon), was defined as the most reliable, expressed by the highest intra- and inter-rater ICCs.

Does an Increase in Supraspinatus Tendon Thickness After Swimming Increase the Likelihood of Future Shoulder Pain?

BACKGROUND

Increase in supraspinatus tendon thickness (STT) resulting from swimming practice has been observed in those with a history of shoulder pain. The magnitude of change in STT after a swimming session and its rate of recovery may be an indicator of future shoulder pain incidence.

HYPOTHESIS

The supraspinatus tendons that demonstrate a greater increase in thickness as a result of swimming practice will have an increased likelihood of future shoulder pain in a cohort of competitive swimmers over a period of 6 months.

DESIGN

Descriptive epidemiology study.

LEVEL OF EVIDENCE

Level 2b, individual cohort studies.

METHODS

A cohort of 50 nationally qualified swimmers aged between 14 and 22 years, from 3 open National Swimming Programs in Victoria, Australia, were recruited for this study. Ultrasonographic measurements of swimmers' STT was obtained of both shoulders, before, immediately after, and 6 hours after a single swimming practice session. Data were recorded of any significant interfering shoulder pain at 3 and 6 months after the initial testing session.

RESULTS

Stepwise logistic regression models indicated that significant predictors of the likelihood of experiencing significant interfering pain were sex [significant at 6 months; odds ratio (OR) 4.2] and the extent of change in STT immediately (OR 2.3 and 1.3 per mm at 3 and 6 months, respectively) and 6 hours postpractice (OR 1.9 and 1.5 per mm at 3 and 6 months, respectively).

CONCLUSION

The current data suggest larger increases in tendon thickness after training are associated with an increased likelihood of future shoulder pain.

CLINICAL RELEVANCE

These data may be valuable for monitoring training load and identifying athletes who may have an increased likelihood of shoulder pain.

Clinical and ultrasound findings of 'swimmer's shoulder' and its association with training history in elite Portuguese swimmers: a cross-sectional study

OBJECTIVES

To assess the prevalence of shoulder injuries and ultrasound findings in elite Portuguese swimmers and their association with symptoms and personal or training-related factors.

METHODS

This cross-sectional study was conducted at the Portuguese Open and Youth Swimming National Championships between 27 and 30th July 2022. Each athlete entered details regarding personal and training history into a questionnaire and underwent a physical and ultrasound shoulder examination.

RESULTS

A total of 102 swimmers out of 662 Portuguese athletes were included in the study. Shoulder pain experienced during the previous season was reported by 42% of the athletes. A high prevalence of shoulder structural abnormalities was noted, specifically supraspinatus tendinosis (91%), tears (29%), and subacromial bursitis (29%). Specific training for injury prevention was associated with higher rates of infraspinatus tendinosis (p = 0.047), and supraspinatus tears were linked to greater swimming distances per week (p < 0.001) and practice (p < 0.001), more years of practice (p = 0.018), shoulder pain at the time of evaluation (p = 0.023), a higher number of missed competitions (p = 0.041), and shoulder injections (p = 0.009). Subacromial bursitis was associated with shoulder pain at the time of evaluation (p = 0.002) and during the previous season (p < 0.001), missed competitions (p < 0.001), and requirement for physical therapy (p = 0.006).

CONCLUSIONS

A high prevalence of shoulder morphological changes was found in surveyed swimmers and there were several associations with training load, regardless of individual characteristics of each athlete. It is essential to understand the true impact of current injury prevention programs and to develop effective measures to protect swimmers' health.

Shoulder structures and strength in competitive preadolescent swimmers: A longitudinal ultrasonographic study

BACKGROUND

Repetitive shoulder movements during competitive training may cause changes in the strength of periarticular shoulder structures in preadolescent swimmers.

OBJECTIVE

To prospectively determine the effects of training on shoulder periarticular structures and muscle strength in preadolescent swimmers.

DESIGN

Prospective cohort study.

SETTING

Community-based natatorium.

PARTICIPANTS

Twenty-four preadolescent swimmers aged 10-12 years.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Measurements were repeated in three periods as preseason, midseason, and postseason. Ultrasonographic measurements (supraspinatus tendon thickness, humeral head cartilage thickness, deltoid muscle thickness, and acromiohumeral distance) were performed using a portable device and a linear probe. Shoulder (flexion, extension, abduction, internal and external rotation) and back (serratus anterior, lower, and middle trapezius) isometric muscle strength were measured with a handheld dynamometer.

RESULTS

Supraspinatus tendon thickness and acromiohumeral distance were similar in all periods (all p > .05); however, deltoid muscle and humeral head cartilage thicknesses increased throughout the season (p = .002, p = .008, respectively). Likewise, whereas shoulder muscle strength increased (all p < .05), back muscle strength was similar in all periods (all p > .05).

CONCLUSIONS

In preadolescent swimmers, acromiohumeral distance and supraspinatus tendon thickness seem to not change; but humeral head cartilage and deltoid muscle thicknesses as well as shoulder muscle strength increase throughout the season.

Subscapularis tendinopathy is highly prevalent in elite swimmer's shoulders: an MRI study

OBJECTIVES

The aim of this study is to determine the prevalence of abnormal anatomical change present on MRI in elite swimmers' shoulders compared to age-matched controls.

DESIGN

Descriptive epidemiological study.

METHODS

Sixty (aged 16-36 years) elite Australian swimmers and 22 healthy active, age and gender matched controls (aged 16-34 years). All participants completed a demographic, and training load and shoulder pain questionnaire and underwent shoulder MRI. Tests for differences in the population proportion was used for comparison between swimmers dominant and non-dominant shoulders and those of the controls.

RESULTS

Subscapularis and supraspinatus tendinopathy was the most common tendon abnormality identified in swimming participants, being reported in at least one shoulder in 48/60 (73 %) and 46/60 (70 %) swimmers, respectively. There was no significant difference between dominant and non-dominant shoulders for either tendinopathy, however, grade 3 tendinopathy was significantly more prevalent in subscapularis than in supraspinatus (P < 0.01). Compared with controls, significantly more abnormalities were reported in swimmers' shoulders in both subscapularis and supraspinatus tendons along with the labrum and acromioclavicular joint. Pathology was not a predictor of current pain.

CONCLUSIONS

This data confirms that tendon abnormality is the most common finding in elite swimmers' shoulders. Furthermore, that subscapularis tendinopathy is not only as common as supraspinatus but has a greater prevalence of grade 3 tendinopathy. With significant varied abnormalities including tendinopathy being so common in both symptomatic and asymptomatic shoulders of swimming athletes', clinicians should consider imaging findings alongside patient history, symptom presentation and clinical examination in determining their relevance in the presenting condition.

Shoulder Tendon Adaptations Following a Graded Exercise Test to Exhaustion in Highly Trained Wheelchair Rugby Athletes With Different Impairments

Objective

This study aimed to identify acute changes in biceps and supraspinatus tendon characteristics before and after a graded exercise test to exhaustion (GXT) in highly trained wheelchair rugby (WR) athletes. A secondary aspect was to define chronic tendon adaptations related to the impairment of the athlete and the occupation of the tendon within the subacromial space (occupation ratio).

Methods

Twelve WR athletes with different impairments (age = 32 ± 6 years; body mass = 67.2 ± 11.2 kg; 9.0 ± 3.6 years competing) volunteered for this study. Performance Corrected Wheelchair Users Shoulder Pain Index was used to quantify shoulder pain. Quantitative Ultrasound Protocols (QUS) were used to define supraspinatus and biceps tendon thickness, echogenicity, and echogenicity ratio of both dominant and non-dominant shoulder before and after the GXT including 22 ± 3.1 min submaximal propulsion and 10.2 ± 1.7 min maximal propulsion on a treadmill. Furthermore, the acromio-humeral distance (AHD) defined from ultrasound (US) images was used to calculate the occupation ratios.

Results

A mixed-effect multilevel analysis that included shoulder as grouping variable, demonstrated a significant reduction in the echogenicity of the biceps following GXT whilst controlling for impairment [spinal cord injury (SCI) and non-SCI] and the occupation ratio (β = −9.01, SEβ = 2.72, p = 0.001, 95% CI = [−14.34; −3.68]). This points toward fluid inflow into the tendon that may be related to overload and acute inflammation. In addition, persons with a SCI (n = 8) had a thicker supraspinatus tendon in comparison to persons with non-SCI (n = 3) which may be related to chronic tendon adaptations (β = −0.53 mm, SEβ = 0.26, p = 0.038, 95% CI = [−1.04; −0.03]). Finally, a greater occupation ratio was associated with signs of tendinopathy (i.e., greater biceps and supraspinatus tendon thickness, and lower supraspinatus echogenicity and echogenicity ratio).

Conclusion

Acute biceps tendon adaptations in response to the GXT in highly trained WR athletes were evident with chronic adaptations in the supraspinatus tendon being related to the impairment of the athlete. Ultrasound can be used to monitor tendon adaptations in WR athletes for medical diagnosis to assist the scheduling and type of training.