Clinical Scenario Quadriceps atrophy and weakness are common after anterior cruciate ligament reconstruction (ACLR). 1 , 2 Blood flow restriction (BFR) therapy, alone or in combination with exercise, has shown some promise in promoting muscular hypertrophy. 1 – 3 This review was conducted to
Lauren Anne Lipker, Caitlyn Rae Persinger, Bradley Steven Michalko and Christopher J. Durall
Samuele Contemori, Andrea Biscarini, Fabio M. Botti, Daniele Busti, Roberto Panichi and Vito E. Pettorossi
structural shoulder alterations that are not directly related to clear detectable clinical symptoms. 6 , 7 These alterations, though asymptomatic, may have a subtle negative impact on performance and may gradually progress in functional loss or limitation. Isolated infraspinatus muscle atrophy (IIMA) is
Samuele Contemori and Andrea Biscarini
a cause or a consequence of common shoulder functional problems. Isolated infraspinatus atrophy (IIA) is a common clinical finding among overhead activity athletes, especially in volleyball and tennis players. 14 , 15 This condition typically affects the hitting shoulder (HS) and results from
Stephanie Di Lemme, Jon Sanderson, Richard G. Celebrini and Geoffrey C. Dover
atrophy and may contribute to a quicker return to competition. 15 , 16 While foot and leg injuries are prevalent in college and professional hockey players and result in a significant loss in playing time, few rehabilitation protocols are available regarding conservative management of talar fractures
Eric Maylia, John A. Fairclough, Leonard D.M. Nokes and Michael D. Jones
Thigh girth is often used as an indicator of muscle hypertrophy or atrophy during the rehabilitation process following knee surgery. The measurement of thigh girth, using a conventional plastic tape measure, in an attempt to detect muscle hypertrophy or atrophy may be misleading. It is an inaccurate measure of thigh muscle bulk. Although the sample size is small, the results show that measurements are heavily biased by the expectations of observers, with the result that a considerable change in thigh girth is likely to be ignored.
Liam Anderson, Graeme L. Close, Matt Konopinski, David Rydings, Jordan Milsom, Catherine Hambly, John Roger Speakman, Barry Drust and James P. Morton
intake and expenditure (using the doubly labeled water [DLW] method) during a 7-day training microcycle occurring 6 weeks after surgery, that is, a time when the athlete may be particularly susceptible to muscle atrophy. In addition, we also present whole body and regional changes in body composition
Miette F. Loopik, Marinus Winters and Maarten H. Moen
No reports have been published on the results of corticosteroid injections for medial tibial stress syndrome (MTSS).
The authors present 2 cases of women with MTSS who showed atrophy and depigmentation of the skin after pretibial corticosteroid injections. Case 1 is an 18-y-old woman presenting with pain in her lower leg for 12 mo. No improvement was noticed after conservative treatment, so she received local injections with corticosteroids. Five months later physical examination showed tissue atrophy and depigmentation around the injection sites. Case 2 is a 22-y-old woman who presented with pain in both lower legs for 24 mo. Several conservative treatment options failed, so she received local injections with corticosteroids. Physical examination revealed tissue atrophy and depigmentation around the injection sites.
No positive effect of injections with corticosteroids was found in 2 cases of MTSS. Furthermore, considerable tissue atrophy and hypopigmentation of the skin was observed.
Emily Arentson-Lantz, Elfego Galvan, Adam Wacher, Christopher S. Fry and Douglas Paddon-Jones
reported in humans, particularly in conjunction with the atrophy response to disuse, and appears to be a sensitive and useful technique for detecting changes in muscle fiber size. Although glucose AUC following 7 days of inactivity did not change in either group, maintenance of glucose control in the CON
Jordan Milsom, Paulo Barreira, Darren J. Burgess, Zafar Iqbal and James P. Morton
The onset of injury and subsequent period of immobilization and disuse present major challenges to maintenance of skeletal muscle mass and function. Although the characteristics of immobilization-induced muscle atrophy are well documented in laboratory studies, comparable data from elite athletes in free-living conditions are not readily available. We present a 6-month case-study account from a professional soccer player of the English Premier League characterizing rates of muscle atrophy and hypertrophy (as assessed by DXA) during immobilization and rehabilitation after ACL injury. During 8 weeks of inactivity and immobilization, where the athlete adhered to a low carbohydrate-high protein diet, total body mass decreased by 5 kg attributable to 5.8 kg loss and 0.8 kg gain in lean and fat mass, respectively. Changes in whole-body lean mass was attributable to comparable relative decreases in the trunk (12%, 3.8 kg) and immobilized limb (13%, 1.4 kg) whereas the nonimmobilized limb exhibited smaller declines (7%, 0.8 kg). In Weeks 8 to 24, the athlete adhered to a moderate carbohydrate-high protein diet combined with structured resistance and field based training for both the lower and upper-body that resulted in whole-body muscle hypertrophy (varying from 0.5 to 1 kg per week). Regional hypertrophy was particularly pronounced in the trunk and nonimmobilized limb during weeks 8 to 12 (2.6 kg) and 13 to 16 (1.3 kg), respectively, whereas the previously immobilized limb exhibited slower but progressive increases in lean mass from Week 12 to 24 (1.2 kg). The athlete presented after the totality of the injured period with an improved anthropometrical and physical profile.
Manu V. Chakravarthy, Frank W. Booth and Espen E. Spangenburg
Approximately 50% of humans older than 85 years have physical frailty due to weak skeletal muscles. This indicates a need for determining mechanisms to combat this problem. A critical cellular factor for postnatal muscle growth is a population of myogenic precursor cells called satellite cells. Given the complex process of sarcopenia, it has been postulated that, at some point in this process, a limited satellite cell proliferation potential could become rate-limiting to the regrowth of old muscles. It is conceivable that if satellite cell proliferative capacity can be maintained or enhanced with advanced age, sarcopenia could potentially be delayed or prevented. Therefore, the purposes of this paper are to describe whether IGF-I can prevent muscular atrophy induced by repeated cycles of hindlimb immobilization, increase the in vitro proliferation in satellite cells from these muscles and, if so, the molecular mechanisms by which IGF-1 mediates this increased proliferation. Our results provide evidence that IGFI can enhance aged muscle regrowth possibly through increased satellite cell proliferation. The results also suggest that IGF-I enhances satellite cell proliferation by decreasing the cell cycle inhibitor, p27Kip1, through the PI3’-K/Akt pathway. These data provide molecular evidence for IGF-I’s rescue effect upon aging-associated skeletal muscle atrophy.