Neovascularization prevalence in the supraspinatus of patients with rotator cuff tendinopathy

Exercise for rotator cuff tendinopathy: Proposed mechanisms of recovery

Rotator cuff (RC) tendinopathy is a common recurrent cause of shoulder pain, and resistance exercise is the first-line recommended intervention. Proposed causal mechanisms of resistance exercise for patients with RC tendinopathy consist of four domains: tendon structure, neuromuscular factors, pain and sensorimotor processing, and psychosocial factors. Tendon structure plays a role in RC tendinopathy, with decreased stiffness, increased thickness, and collagen disorganization. Neuromuscular performance deficits of altered kinematics, muscle activation, and force are present in RC tendinopathy, but advanced methods of assessing muscle performance are needed to fully assess these factors. Psychological factors of depression, anxiety, pain catastrophizing, treatment expectations, and self-efficacy are present and predict patient-reported outcomes. Central nervous system dysfunctions also exist, specifically altered pain and sensorimotor processing. Resisted exercise may normalize these factors, but limited evidence exists to explain the relationship of the four proposed domains to trajectory of recovery and defining persistent deficits limiting outcomes. Clinicians and researchers can use this model to understand how exercise mediates change in patient outcomes, develop subgroups to deliver patient-specific approach for treatment and define metrics to track recovery over time. Supporting evidence is limited, indicating the need for future studies characterizing mechanisms of recovery with exercise for RC tendinopathy.

Shoulder complaints more likely in volleyball players with a thickened bursa or supraspinatus tendon neovessels

Shoulder problems are common in volleyball and greatly impede both training and player performance. Subacromial bursa (SAB) thickening and tendon neovascularity have shown relevance in other populations, but their relationship with the development of shoulder complaints has not been investigated in volleyball players or overhead-throwing athletes. The study aim was to examine the role of SAB thickness, neovascularization of the supraspinatus tendon, shoulder strength, range of motion (ROM), player position, and age in the development of shoulder complaints in professional volleyball players. Players underwent preseason baseline testing (n = 86) and reported shoulder complaints during the subsequent 12-week period. Generalized estimating equations were used to model for probabilities of complaints after adjusting for player position, SAB side-to-side difference, neovessel presence, shoulder external rotation (ER) ROM, and age. Outside hitters and opposites were 12.2-fold more likely to develop complaints, and greater shoulder ER ROM increased risk by 8% for each additional degree. A side-to-side difference in SAB thickness ≥0.3 mm in the dominant compared with the non-dominant arm was associated with a 10.2-fold increased risk. Those with neovessels were 6.5 times more likely to develop complaints. Players without neovessels and with normal SAB thickness were very unlikely to develop complaints. This stark contrast to players with neovessels or increased SAB thickness, where nearly half of the players developed complaints, is of interest. Players with current complaints at baseline presented with greater IR:ER strength ratios; however, neither strength nor IR ROM at baseline was associated with an increased risk of developing complaints.

Tendinopathy: Investigating the Intersection of Clinical and Animal Research to Identify Progress and Hurdles in the Field

Biological treatments, surgical interventions, and rehabilitation exercises have been successfully used to treat tendinopathy, but the development of effective treatments has been hindered by the lack of mechanistic data regarding the pathogenesis of the disease. While insightful, clinical studies are limited in their capacity to provide data regarding the pathogenesis of tendinopathies, emphasizing the value of animal models and cell culture studies to fill this essential gap in knowledge. Clinical pathological findings from imaging studies or histological analysis are not universal across patients with tendinopathy and have not been clearly associated with the onset of symptoms. There are several unresolved controversies, including the cellular changes that accompany the tendinopathic disease state and the role of inflammation. Additional research is needed to correlate the manifestations of the disease with its pathogenesis, with the goal of reaching a field-wide consensus on the pathology of the disease state. Such a consensus will allow standardized clinical practices to more effectively diagnose and treat tendinopathy.

Tendon vascularity in overhead athletes with subacromial pain syndrome and its correlation with the resting subacromial space

BACKGROUND

Supraspinatus tendinopathy is one of the common causes of subacromial pain syndrome (SAPS) in overhead athletes. Changes in tendon vascularity have been reported in painful tendons; however, the prevalence and distribution have not been investigated in young overhead athletes.

METHODS

We conducted a cross-sectional study of 47 overhead athletes (male, 31; female, 16) aged 18 to 36 years with SAPS for >3 months. A sonographer graded the severity of the tendinopathy and area of vascularization. Ultrasound imaging was used to measure supraspinatus tendon thickness, vascularity, and resting subacromial space. A self-written program was used to semiquantify the intensity of vascularity, expressed as the vascular index.

RESULTS

The majority (87.2%) of the participants had signs of tendinopathy in the supraspinatus tendon, and 40 (85.1%) of the tendinopathic tendons had vascularity. The majority (66.0%) of the vascularized subjects presented with minimal increase in vascularity, and 19.1% had moderate to severe vascularization. Most (79.2%) of the vascularization was observed in the pericortical region. The vascular index was negatively correlated with the resting subacromial space in male athletes with a reduced subacromial space (ρ = -0.63; P = .038).

CONCLUSION

Of overhead athletes with SAPS, 87.2% had supraspinatus tendinopathy with minimal to moderate vascularization, with the majority of vascularization occurring in the pericortical region. In male athletes with a reduced subacromial space, greater vascularity in the supraspinatus tendon was associated with a smaller resting subacromial space.

At What Age Do Children and Adolescents Develop Lower Limb Tendon Pathology or Tendinopathy? A Systematic Review and Meta-analysis

BACKGROUND

Tendon pathology and tendinopathy have been reported in children and adolescents; however, the age at onset and prevalence of the conditions have not been examined systematically.

OBJECTIVE

To examine the prevalence of lower limb tendon pathology and tendinopathy in children and adolescents, and the factors associated with these conditions in this population.

METHODS

Six databases were searched (MEDLINE, the Cochrane Central Register of Controlled Trials, Embase, Scopus, the Web of Science and the Allied and Complementary Medicine Database). Studies were included if the prevalence of lower limb tendon pathology and/or tendinopathy were reported in humans under the age of 18 years. Studies were divided according to the method of diagnosis (physical examination, ultrasound or a questionnaire) and further divided into studies that reported prevalence data by tendon [reported two data points (right and left) for each participant] and those that reported prevalence data for each participant [reporting one data point (right or left) per participant].

RESULTS

Seventeen studies met the inclusion criteria. Lower limb tendinopathy prevalence (presence of pain and dysfunction) ranged between 8.2 and 33.3%, and increased in prevalence as age increased up to 18 years. The odds ratio for studies reporting tendinopathy by tendon was 0.37 (95% confidence interval 0.20-0.69) in favour of boys presenting with tendinopathy. Study aims and reporting methods were heterogeneous.

CONCLUSIONS

The age at onset of lower limb tendinopathy in children and adolescents has not been widely studied. This systematic review found that tendinopathy is present in children and adolescents, and increases in prevalence with age up to 18 years. Male sex is significantly associated with tendinopathy in studies that report tendinopathy by tendon.

Ultrasound assessment for grading structural tendon changes in supraspinatus tendinopathy: an inter-rater reliability study

AIM

To evaluate the inter-rater reliability of measuring structural changes in the tendon of patients, clinically diagnosed with supraspinatus tendinopathy (cases) and healthy participants (controls), on ultrasound (US) images captured by standardised procedures.

METHODS

A total of 40 participants (24 patients) were included for assessing inter-rater reliability of measurements of fibrillar disruption, neovascularity, as well as the number and total length of calcifications and tendon thickness. Linear weighted κ, intraclass correlation (ICC), SEM, limits of agreement (LOA) and minimal detectable change (MDC) were used to evaluate reliability.

RESULTS

'Moderate-almost perfect' κ was found for grading fibrillar disruption, neovascularity and number of calcifications (k 0.60-0.96). For total length of calcifications and tendon thickness, ICC was 'excellent' (0.85-0.90), with SEM(Agreement) ranging from 0.63 to 2.94 mm and MDC(group) ranging from 0.28 to 1.29 mm. In general, SEM, LOA and MDC showed larger variation for calcifications than for tendon thickness.

CONCLUSIONS

Inter-rater reliability was moderate to almost perfect when a standardised procedure was applied for measuring structural changes on captured US images and movie sequences of relevance for patients with supraspinatus tendinopathy. Future studies should test intra-rater and inter-rater reliability of the method in vivo for use in clinical practice, in addition to validation against a gold standard, such as MRI.

TRIAL REGISTRATION NUMBER

NCT01984203; Pre-results.

Not All Tendons Are Created Equal: Implications for Differing Treatment Approaches

The majority of muscles have distinct tendinous attachments to bones; however, only a few tendons develop painful conditions. That simple observation prompts us to ask a few questions. Are there commonalities in morphology and pathology among the painful tendons? What contributes to the propensity for pathology in some, but not all, tendons? And, consequently, should all tendinopathies be managed equally? Two common tendinopathies are those affecting the Achilles and supraspinatus, which are presented in this special issue and serve as excellent models to discuss similarities and contrasts. J Orthop Sports Phys Ther 2015;45(11):829-832. doi:10.2519/jospt.2015.0114.

Sonographic Evaluation of the Plantar Heel in Asymptomatic Endurance Runners

OBJECTIVES

The primary purpose of this investigation was to determine the prevalence and spectrum of asymptomatic sonographically determined structural changes in the plantar fascia and plantar heel pad among experienced runners without a history of heel pain.

METHODS

Thirty-nine asymptomatic runners without a history of plantar heel pain were recruited. The following sonographic measures were recorded: power Doppler sonography in the plantar heel pad and plantar fascia, echo texture of the plantar heel pad, uncompressed heel pad thickness, compressed heel pad thickness, heel pad compressibility index, plantar fascia thickness, and plantar fascia echo texture.

RESULTS

Doppler flow was shown in the plantar heel pads of 88% (68 of 77) of heels and 92% (36 of 39) of runners. Heel pad echo texture abnormalities were found in 86% (66 of 77) of heels and 97% (38 of 39) of runners. Mean values for right and left uncompressed heel pad thickness were 13.8 and 13.7 mm, respectively. The mean heel pad compressibility indices were 0.51 for the right heel and 0.53 for the left heel. Eight percent (6 of 77) of fat pads in 10% (4 of 39) of runners had abnormal compressibility indices. Doppler flow was present in the plantar fascia in 31% (24 of 77) of heels and 44% (17 of 39) of runners. The mean plantar fascia thicknesses were 3.78 mm for the right and 3.87 mm for the left. Forty-eight percent (37 of 77) of heels had an abnormal plantar fascia echo texture.

CONCLUSIONS

At least 1 potentially abnormal sonographic finding was present in each heel of all asymptomatic runners in this study. Consequently, sonographic abnormalities in the plantar heel should be interpreted within the clinical context when evaluating runners.