Relationship between sarcopenia classification and thigh muscle mass, fat area, muscle CT value and osteoporosis in middle-aged and older Japanese adults.

Sarcopenia is one of the most important health issues in today's ageing society. As an evaluation method, computed tomography (CT) is an effective means of assessing not only the quantity but also the quality of skeletal muscle. We aimed to examine the relationship between sarcopenia severity and muscle/fat area, and osteoporosis. 321 patients (116 men and 205 women, mean age 77.2 ± 7.1 years, age range 53-96 years) who visited the Integrated Healthy Aging Clinic from 2016 to 2017 were included in this study. Based on the Asia Working Group for Sarcopenia2019 criteria, patients were divided into four groups: normal group, low-functional group (with normal skeletal muscle mass, but reduced muscle strength or physical function), sarcopenia group, and severe sarcopenia group. We measured the skeletal muscle (SM), intermuscular adipose tissue (IMAT), and subcutaneous adipose tissue (SAT) areas and the CT attenuation values (CTV) using cross sections of the mid-thigh CT. We also measured bone mineral density. Then, we compared each result among the four groups. We found a significant decrease in SM area in both men and women with sarcopenia (p < 0.001 for both sexes). In women, a decrease in SAT area was observed in the sarcopenia group (p < 0.001), and an increase in IMAT was observed in the low functional group (p < 0.001). The CTV decreased in men with sarcopenia and severe sarcopenia; similarly, women in the low functional and severe sarcopenia groups had decreased CTV (p < 0.001 for both sexes). An association between sarcopenia and osteoporosis in men was detected (p = 0.004). By using not only muscle mass but also fat mass and CTV, we were able to better examine the pathogenesis of sarcopenia and differences between men and women in Japanese middle-aged and older adults.

Scapular Winging following Sports-Related Injury in a Rugby Player.

The most common cause of medial scapular winging is long thoracic nerve palsy (LTN) and subsequent serratus anterior muscle dysfunction. A 16-year-old right-handed male high-school rugby player developed severe right-sided neck and shoulder pain after tackling an opponent while playing rugby. Six weeks after initial injury, the patient observed shoulder muscle weakness when performing his daily activities. On physical examination, limited active elevation of the right shoulder in the scapular plane and scapular winging was observed. Magnetic resonance imaging revealed atrophy of both the SA and subclavius muscles on the right side, and we initially suspected an LTN injury sustained. However, while detailing his history, the patient explained that he also had noted difficulty sucking high viscosity drinks such as shakes and smoothies since childhood. In addition, physical examination showed weakness of the orbicularis oculi muscle. Considering the facial muscle weakness, facioscapulohumeral dystrophy (FSHD) was also suspected, and genetic testing showed chromosome 4q35 deletion with restriction fragments 17 kb and 3 tandem repeated DNA confirming the diagnosis of FSHD. Clinicians should be aware that FSHD could be one of the differential diagnoses of scapular winging after sports injury, and surgeons should rule out the diagnosis of FSHD before performing any surgical treatment for SA palsy.

4-Methylumbelliferone suppresses catabolic activation in anterior cruciate ligament-derived cells via a mechanism independent of hyaluronan inhibition.

BACKGROUND: The anterior cruciate ligament (ACL) has a key role as a dynamic stabilizer of the knee joints, and ACL dysfunction caused by traumatic or degenerative rupture accelerates osteoarthritis progression. Thus, it is important to prevent the degenerative rupture of the ACL. 4-Methylumbelliferone (4-MU), a pre-approved drug, exerts anti-inflammatory effects in osteoarthritis chondrocytes. It was originally used as an inhibitor of hyaluronan synthesis in chondrocytes. METHODS: In this study, we investigated whether 4-MU affects the expression of catabolic factors, such as matrix metalloproteinase (MMP)-1, MMP-3, and interleukin (IL)-6, in ACL-derived cells and ACL explant cultures using immunohistochemistry, real-time RT-qPCR, and capillary western immunoassay. Furthermore, the hyaluronan concentration was evaluated using a colorimetric assay. Statistical analyses were conducted using analysis of variance for multi-group comparisons, followed by Tukey or Tukey-Kramer post hoc test. RESULTS: Our results revealed, for the first time, that 4-MU suppressed the IL-ß-induced upregulation of pro-catabolic factors, such as MMP-1, MMP-3, and IL-6, in ACL-derived cells. This suppressive effect was also observed in the cultured ligament tissues in ex vivo experiments. 4-MU also reversed an enhanced dependence on glycolysis in IL-1ß-activated ACL-derived cells. Furthermore, we found that the suppressive effects of 4-MU were exerted directly and not through the inhibition of hyaluronan synthesis. CONCLUSIONS: We conclude that 4-MU could be an effective and useful treatment for knee osteoarthritis, owing to its anti-inflammatory effect on, not only chondrocytes but also on ligament cells.

Spontaneous Pneumomediastinum in an Adolescent Soccer Player.

Spontaneous pneumomediastinum (SPM) is an uncommon and usually benign self-limiting clinical disorder found in young people, often without apparent precipitating factors or diseases. A pressure gradient exists between the peripheral pulmonary alveoli and the hilum, and increased intra-alveolar pressure causes rupture of the terminal alveoli. We present the case of a 15-year-old male soccer player who presented with a complaint of anterior chest pain and dysphagia after stopping the strong ball with his chest. His symptom gradually progressed over hours. We can make the diagnosis of SPM using by chest X-ray and computed tomography (CT) scanning. His symptoms were gradually resolved over the course of approximately one week with no exercise and careful observation. We believe that our case provides very useful information to alert clinicians and coaches regarding this rare disease that may occur in anyone including adolescent soccer players.