Changes on Tendon Stiffness and Clinical Outcomes in Athletes Are Associated With Patellar Tendinopathy After Eccentric Exercise.

OBJECTIVE: Eccentric exercise is commonly used as a form of loading exercise for individuals with patellar tendinopathy. This study investigated the change of mechanical properties and clinical outcomes and their interrelationships after a 12-week single-legged decline-board exercise with and without extracorporeal shockwave therapy (ESWT). DESIGN: Randomized controlled trial. SETTING: Outpatient clinic of a university. PARTICIPANTS: Thirty-four male in-season athletes with patellar tendinopathy for more than 3 months were randomized into exercise and combined groups. INTERVENTIONS: The exercise group received a 12-week single-legged decline-squat exercise, and the combined group performed an identical exercise program in addition to a weekly session of ESWT in the initial 6 weeks. MAIN OUTCOME MEASURES: Tendon stiffness and strain were examined using ultrasonography and dynamometry. Visual analog scale and Victoria Institute of Sports Assessment-patella (VISA-p) score were used to assess pain and dysfunction. These parameters were measured at preintervention and postintervention. RESULTS: Significant time effect but no significant group effect on the outcome measures; significant reduction in tendon stiffness (P = 0.02) and increase in tendon strain (P = 0.00); and reduction of intensity of pain (P = 0.00) and dysfunction (P = 0.00) were observed. Significant correlations between changes in tendon stiffness and VISA-p score (ρ = -0.58, P = 0.05); alteration in tendon strain, pain intensity (ρ = -0.63, P = 0.03); and VISA-p score (ρ = 0.60, P = 0.04) were detected after the exercise program. CONCLUSIONS: Eccentric exercise-induced modulation on tendon mechanical properties and clinical symptoms are associated in athletes with patellar tendinopathy.

Enforced bipedal downhill running induces Achilles tendinosis in rats.

Enforced downhill running has been reported to induce tendinosis in the rat supraspinatus tendon but similar exercise failed to induce Achilles tendinosis in this animal. Due to the presence of acromial arch in the shoulder, accessing the supraspinatus tendon with physical modalities is difficult; thus this model may not be suitable for studying the treatment for tendinosis. To develop a rat model for Achilles tendinosis, we tested 14 mature Sprague-Dawley rats by dividing them into 2 groups of 7 each. The experimental group was subjected to a daily enforced downhill bipedal running program by suspending their upper bodies so that they ran with their hind limbs on a treadmill for 1 hr/day for 8 weeks. The downward inclination was 20 degrees and the speed was 17 m/min. The animals in the control group did not undergo any exercise. After 8 weeks, the Achilles tendons were harvested and subjected to histological and biomechanical analysis. Histological examination revealed tenocyte proliferation, change in tenocytes appearance, and collagen bundle disintegration in the running group. The biomechanical testing revealed significant decrease in stiffness (p = 0.002) and ultimate tensile strength (p = 0.016) in the running group than in the control group. Both the histological and biomechanical findings are suggestive of changes in the tendon of the running group that resembled the pathological changes of tendinosis in human. This new model of Achilles tendinosis in rat will be useful for studying the etiology and subsequent management strategies of this condition.

Effects of scapular taping on the activity onset of scapular muscles and the scapular kinematics in volleyball players with rotator cuff tendinopathy.

OBJECTIVES: To examine the effect of scapular taping on the activity onset of scapular muscles and the scapular kinematics during arm elevation in volleyball players with rotator cuff (RC) tendinopathy. DESIGN: Randomized placebo-controlled repeated measures METHODS: Twenty-six male volleyball players with RC tendinopathy (mean age=23.6±3.3years) participated in the study. Electromyography (EMG) activity onset of upper trapezius (UT), middle trapezius (MT), lower trapezius (LT) and serratus anterior (SA) and the three-dimensional scapular kinematics quantified by using an acromial marker cluster method were compared with three scapular taping protocols, namely, no taping, therapeutic taping, and placebo taping. RESULTS: The MT, LT and SA activated significantly earlier in both therapeutic taping (all p<0.005) and placebo taping conditions than no taping conditions (all p<0.002). There was a small increase in the scapular upward rotation when therapeutic taping and no taping conditions were compared (p=0.007). CONCLUSIONS: Scapular taping may enhance the neuromotor control of the scapular muscles. Whether it provides adequate support for normal scapular kinematics during arm movement in athletes with RC tendinopathy await for further studies.

Rotator cuff tendinopathy alters the muscle activity onset and kinematics of scapula.

Athletes with rotator cuff (RC) tendinopathy demonstrate an aberrant pattern of scapular motion which might relate to deficits in the scapular muscles. This study aimed to determine whether alteration in scapular kinematics is associated with deficits in the activity onset of scapular muscles. Forty-three male volleyball players (17 asymptomatic and 26 with RC tendinopathy) joined the study. Three-dimensional scapular kinematics was quantified using an acromial marker cluster method. The activity onset of the upper (UT), middle (MT), and lower trapezius (LT), and serratus anterior (SA) during arm abduction was assessed with electromyography. Athletes with RC tendinopathy demonstrated less scapular upward rotation (6.6±2.3 vs. 8.2±1.1°, p=0.021) in the early phase of shoulder abduction from 0° to 30° when compared to asymptomatic athletes. The tendinopathy group had delayed activity onset of LT (14.1±31.4ms vs. 74.4±45.1ms, p<0.001) and SA (-44.9±26.0ms vs. 23.0±25.2ms, p<0.001) relative to UT when compared to the asymptomatic group. In asymptomatic athletes, earlier activity onset of MT and LT relative to UT was associated with more scapular upward rotation during 0-30° of abduction (r=0.665, p=0.021) and 30-60° of abduction (r=0.680, p=0.015), respectively. Our findings showed the control of the scapular upward rotation is related to the activity onset of the scapular muscles in athletes.

Reduction of the subacromial space in athletes with and without rotator cuff tendinopathy and its association with the strength of scapular muscles.

OBJECTIVES: To compare the reduction of subacromial space (SAS) during arm abduction between overhead athletes with and without rotator cuff (RC) tendinopathy, and to explore the relationship between the strength of scapular muscles with the SAS. DESIGN: Cross-sectional study. METHODS: Sixty-six athletes (33 healthy and 33 with RC tendinopathy, mean age=22.3 years) participated in the study. Ultrasound measurement of the SAS with arm at 0°, 30° and 60° of shoulder abduction were taken, and the maximal isometric force in upper, middle and lower trapezius, and serratus anterior with manual muscle tests (MMT) were assessed using a handheld dynamometer. The change in SAS during arm abduction from 0° to 30° (SAS0°-30°), 30° to 60° (SAS30°-60°) and 0° to 60° (SAS0°-60°) was compared between groups. Differences in force produced with scapular muscles MMT between groups and relationships with reduction in SAS were explored. RESULTS: We found more reduction of the SAS during SAS0°-30° in athletes with RC tendinopathy (0.44±1.22mm) than healthy athletes (-0.06±1.41mm) (p=0.045). Athletes with RC tendinopathy demonstrated significant decrease in all scapular muscles MMT strength when compared to their healthy counterparts (p<0.05). In healthy athletes, a lower middle and lower trapezius MMT strength were moderately associated with a greater reduction in SAS during 0° to 30° (r=-0.445, p=0.016 and r=-0.423, p=0.022, respectively) and 0° to 60° of shoulder abduction (r=-0.415, p=0.018 and r=-0.504, p=0.003, respectively). CONCLUSIONS: Athletes with RC tendinopathy demonstrated more reduction in the SAS during early arm abduction. Decreased strength of middle and lower trapezius was related to reduction of the SAS.

A randomised controlled trial of the effectiveness of an exercise training program in patients recovering from severe acute respiratory syndrome.

The aim of this study was to evaluate the effectiveness of an exercise training program on cardiorespiratory and musculoskeletal performance and health-related quality of life of patients who were recovering from severe acute respiratory syndrome (SARS). A 6-week supervised exercise training program was carried out in the physiotherapy department of a university teaching hospital. One hundred and thirty-three patients referred from a SARS Review Clinic solely for physiotherapy were included. Cardiorespiratory fitness (6-minute walk test, Chester Step Test for predicting VO(2max)), musculoskeletal performance (isometric deltoid and gluteal muscles strength, handgrip strength, 1-minute curl-up and push-up tests) and health-related quality of life (SF-36) were measured and evaluated. Patients were assigned randomly to either a control group (standardised educational session about exercise rehabilitation) or an exercise group. After 6 weeks, significantly greater improvement was shown in the exercise group in the 6-minute walk test (77.4 m vs 20.7 m, p < 0.001), VO(2max) (3.6 ml/kg/min vs 1 ml/kg/min, p = 0.04), and musculoskeletal performance (handgrip strength, curl-up and push-up tests, p < 0.05). Effects on health-related quality of life were not statistically significant. It was concluded that the exercise training program was effective in improving both the cardiorespiratory and musculoskeletal fitness in patients recovering from SARS. However, health-related quality of life was not affected by physical training.

Changes in morphological and elastic properties of patellar tendon in athletes with unilateral patellar tendinopathy and their relationships with pain and functional disability.

BACKGROUND: Patellar tendinopathy (PT) is one of the most common knee disorders among athletes. Changes in morphology and elasticity of the painful tendon and how these relate to the self-perceived pain and dysfunction remain unclear. OBJECTIVES: To compare the morphology and elastic properties of patellar tendons between athlete with and without unilateral PT and to examine its association with self-perceived pain and dysfunction. METHODS: In this cross-sectional study, 33 male athletes (20 healthy and 13 with unilateral PT) were enrolled. The morphology and elastic properties of the patellar tendon were assessed by the grey and elastography mode of supersonic shear imaging (SSI) technique while the intensity of pressure pain, self-perceived pain and dysfunction were quantified with a 10-lb force to the most painful site and the Victorian Institute of Sport Assessment-patella (VISA-P) questionnaire, respectively. RESULTS: In athletes with unilateral PT, the painful tendons had higher shear elastic modulus (SEM) and larger tendon than the non-painful side (p<0.05) or the dominant side of the healthy athletes (p<0.05). Significant correlations were found between tendon SEM ratio (SEM of painful over non-painful tendon) and the intensity of pressure pain (rho  = 0.62; p = 0.024), VISA-P scores (rho  = -0.61; p = 0.026), and the sub-scores of the VISA-P scores on going down stairs, lunge, single leg hopping and squatting (rho ranged from -0.63 to -0.67; p<0.05). CONCLUSIONS: Athletes with unilateral PT had stiffer and larger tendon on the painful side than the non-painful side and the dominant side of healthy athletes. No significant differences on the patellar tendon morphology and elastic properties were detected between the dominant and non-dominant knees of the healthy control. The ratio of the SEM of painful to non-painful sides was associated with pain and dysfunction among athletes with unilateral PT.

Quantitative estimation of muscle shear elastic modulus of the upper trapezius with supersonic shear imaging during arm positioning.

Pain and tenderness of the upper trapezius are the major complaints among people with chronic neck and shoulder disorders. Hyper-activation and increased muscle tension of the upper trapezius during arm elevation will cause imbalance of the scapular muscle force and contribute to neck and shoulder disorders. Assessing the elasticity of the upper trapezius in different arm positions is therefore important for identifying people at risk so as to give preventive programmes or for monitoring the effectiveness of the intervention programmes for these disorders. This study aimed to establish the reliability of supersonic shear imaging (SSI) in quantifying upper trapezius elasticity/shear elastic modulus and its ability to measure the modulation of muscle elasticity during arm elevation. Twenty-eight healthy adults (15 males, 13 females; mean age = 29.6 years) were recruited to participate in the study. In each participant, the shear elastic modulus of the upper trapezius while the arm was at rest and at 30° abduction was measured by two operators and twice by operator 1 with a time interval between the measurements. The results showed excellent within- and between-session intra-operator (ICC = 0.87-0.97) and inter-observer (ICC = 0.78-0.83) reliability for the upper trapezius elasticity with the arm at rest and at 30° abduction. An increase of 55.23% of shear elastic modulus from resting to 30° abduction was observed. Our findings demonstrate the possibilities for using SSI to quantify muscle elasticity and its potential role in delineating the modulation of upper trapezius elasticity, which is essential for future studies to compare the differences in shear elastic modulus between normal elasticity and that of individuals with neck and shoulder disorders.

The impact of severe acute respiratory syndrome on the physical profile and quality of life.

OBJECTIVE: To investigate the impact of severe acute respiratory syndrome (SARS) on the physical fitness and health-related quality of life (HRQOL) among SARS survivors. DESIGN: A cohort study. SETTING: An outpatient physiotherapy department in a major hospital in Hong Kong. PARTICIPANTS: SARS patients (N=171) discharged from the hospital. Their mean age was 37.36+/-12.65 years, and the average number of days of hospitalization was 21.79+/-9.93 days. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Subjects cardiorespiratory (6-minute walk test [6MWT], Chester step test for predicting maximal oxygen uptake [Vo 2 max]), musculoskeletal (proximal/distal muscle strength and endurance test), and HRQOL status (Medical Outcomes Study 36-Item Short-Form Health Survey [SF-36]) were measured and compared with the normative data matched for age and sex. RESULTS: Seventy-eight (45.61%) patients continued to require prednisolone (< 0.5mg.kg -1 .d -1 ) for residual lung opacities when data were collected. The values of 6MWT distance, predicted Vo 2 max, proximal and distal muscle strength, and the scores from all SF-36 domains, particularly perceived role-physical, were significantly lower than the normative data ( P <.05). CONCLUSIONS: SARS survivors had deficits in cardiorespiratory and musculoskeletal performance, and their HRQOL appeared to be significantly impaired.