Quadriceps Atrophy Research Articles

Outpatient Physical Therapy Evaluation and Treatment of a Patient Diagnosed with Sporadic Inclusion Body Myositis: A Case Study

Background: Sporadic inclusion body myositis is an autoimmune and degenerative disorder of skeletal muscle that affects people at random. It most commonly begins as progressive weakness and atrophy of lower extremity musculature, beginning with the proximal leg. These impairments in body structure adversely affect the performance of functional activities and mobility, resulting in a progressive decrease in independence and participation both at home and in the community. Physical therapy attempts to minimize these effects through educational and procedural interventions focused on treating impairments and limitations. The purpose of this case study was to provide a description of the physical therapy management of a patient diagnosed with sporadic inclusion body myositis.Case Summary: The patient was a 66-year-old male who was diagnosed with sporadic inclusion body myositis with a chief complaint of weakness and fall risk. He presented with generalized lower extremity weakness and atrophy of bilateral quadriceps, as well as impaired balance and increasing fatigue with activity. Therapeutic exercise, home exercise program, balance, gait, and stair training were delivered to address these impairments. Patient outcomes showed improvement in balance and safety with functional activities.Discussion: The patient was seen for seven visits that were 45 – 60 minutes in length, over a five-week period. The patient made subjective reports of improvement in functional activities and balance; however many objective outcome measures could not be reassessed. There is a need for further research on this population to determine the effectiveness and parameters of physical therapy interventions.Conclusion: Physical therapy may have helped improve balance as well as subjective reports from the patient of increased feeling of confidence while navigating stairs.

Panoramic ultrasound: a novel and valid tool for monitoring change in muscle mass.

BackgroundThe strong link between reduced muscle mass and morbidity and mortality highlights the urgent need for simple techniques that can monitor change in skeletal muscle cross‐sectional area (CSA). Our objective was to examine the validity of panoramic ultrasound to detect change in quadriceps and gastrocnemius size in comparison with magnetic resonance imaging (MRI) in subjects randomized to 70 days of bed rest (BR) with or without exercise.MethodsPanoramic ultrasound and MRI images of the quadriceps and gastrocnemius muscles were acquired on the right leg of 27 subjects (26 male, 1 female; age: 34.6 ± 7.8 years; body mass: 77.5 ± 10.0 kg; body mass index: 24.2 ± 2.8 kg/m2; height: 179.1 ± 6.9 cm) before (BR‐6), during (BR3, 7, 11, 15, 22, 29, 36, 53, 69), and after (BR+3, +6, +10) BR. Validity of panoramic ultrasound to detect change in muscle CSA was assessed by Bland–Altman plots, Lin's concordance correlation coefficient (CCC), sensitivity, specificity, positive predictive value, and negative predictive value.ResultsSix hundred ninety‐eight panoramic ultrasound CSA and 698 MRI CSA measurements were assessed. Concordance between ultrasound and MRI was excellent in the quadriceps (CCC: 0.78; P < 0.0001), whereas there was poor concordance in the gastrocnemius (CCC: 0.37; P < 0.0006). Compared with MRI, panoramic ultrasound demonstrated high accuracy in detecting quadriceps atrophy and hypertrophy (sensitivity: 73.7%; specificity: 74.2%) and gastrocnemius atrophy (sensitivity: 83.1%) and low accuracy in detecting gastrocnemius hypertrophy (specificity: 33.0%).ConclusionsPanoramic ultrasound imaging is a valid tool for monitoring quadriceps muscle atrophy and hypertrophy and for detecting gastrocnemius atrophy.

Villonodular synovitis of the knee: about 20 cases

La synovite villonodulaire pigmentée (SVNP) est une prolifération bénigne rare de la synoviale des articulations, des bourses séreuses et des gaines tendineuses, d'étiopathogénie inconnue. Notre travail porte sur 20 cas de SVN du genou colligés à l'hôpital militaire Avicenne de Marrakech sur une période de 9 ans allant de janvier 2000 au décembre 2009 Il vise à identifier les spécificités de cette lésion, et à étudier ses principaux aspects anatomocliniques et pronostiques. L'incidence annuelle était de 2,2 cas par an. Ils étaient 15 hommes et 5 femmes, d'âge moyen de 32,5 ans, atteints du coté droit dans 55%des cas sous un mode mono articulaire chez 18 patients et bi articulaire chez un seul. La douleur et la tuméfaction étaient présentes dans 80% des cas, une masse palpable dans un cas, un syndrome méniscal a été retenu dans un cas, une mono arthrite septique dans 3 circonstances de même qu'un kyste poplité dans 2 autres. L'atteinte était diffuse dans 14 cas (70%), localisée dans 6 cas. L'imagerie par résonnance magnétique(IRM) pratiquée chez 5 patients était évocatrice chez 3, l'arthroscopie diagnostique a été utilisée chez 2 malades. La confirmation s'est faite à chaque fois à l'examen anatomopathlogique. Le traitement a consisté en une synovectomie subtotale dans 15 cas et en l'exérèse de la tumeur dans les autres formes localisées, 2 cas présentant une destruction ostéocartilagineuse ont nécessité une arthroplastie. L'évolution a été marquée par la survenue de 2 récidives sous la forme diffuse avec un recul de 3, 7 ans. On a noté une raideur avec atrophie quadricipitale chez 3 patients et une arthrolyse a été réalisée. Un cas de SVN confirmé par l'histologie s'est révélé être 5 mois après la synovectomie totale un Synovialosarcome monophasique envahissant l'os d'où l'indication de l'amputation.

Mechanisms of Chronic Muscle Wasting and Dysfunction after an Intensive Care Unit Stay. A Pilot Study.

Critical illness survivors often experience permanent functional disability due to intensive care unit (ICU)-acquired weakness. The mechanisms responsible for long-term weakness persistence versus resolution are unknown. To delineate cellular mechanisms underlying long-term weakness persistence in ICU survivors. We conducted a nested, prospective study of critically ill patients mechanically ventilated for 7 days or longer. The patients were recruited from the RECOVER program and serially assessed over 6 months after ICU discharge. Twenty-seven of 82 patients consented to participate; 15 and 11 patients were assessed at 7 days and 6 months after ICU discharge, respectively. We assessed motor functional capacity, quadriceps size, strength, and voluntary contractile capacity and performed electromyography, nerve conduction studies, and vastus lateralis biopsies for histologic, cellular, and molecular analyses. Strength and quadriceps cross-sectional areas were decreased 7 days after ICU discharge. Weakness persisted to 6 months and correlated with decreased function. Quadriceps atrophy resolved in 27% patients at 6 months. Muscle mass reconstitution did not correlate with resolution of weakness, owing to persistent impaired voluntary contractile capacity. Compared with Day 7, increased ubiquitin-proteasome system-mediated muscle proteolysis, inflammation, and decreased mitochondrial content all normalized at 6 months. Autophagy markers were normal at 6 months. Patients with sustained atrophy had decreased muscle progenitor (satellite) cell content. Long-term weakness in ICU survivors results from heterogeneous muscle pathophysiology with variable combinations of muscle atrophy and impaired contractile capacity. These findings are not explained by ongoing muscle proteolysis, inflammation, or diminished mitochondrial content. Sustained muscle atrophy is associated with decreased satellite cell content and compromised muscle regrowth, suggesting impaired regenerative capacity.

Iliopsoas Hemorrhage in Pediatric Patients with Hemophilia, Experience from One Centre

Introduction: Iliopsoas hematoma is a serious, life threatening bleeding event in patients with hereditary clotting disorders and significantly associated with morbidity. It occurs most commonly in patients with severe hemophilia (Balkan et al Haemophilia 2005). In this review, we evaluated our patients with iliopsoas hematoma and compared with literature.Methods: The eleven pediatric patients with hemophilia and iliopsoas hematoma treated in a research and training hospital in Istanbul, between 2005 and 2015 were enrolled. The clinical characteristics including symptoms, signs, complications, and treatment were analyzed retrospectively.Results: We evaluated 14 episodes of iliopsoas hematoma from 11 patients (10 hemophilia A and 1 hemophilia B). All patients were male and the median age was 12 (8 -14) years old. Eight patients had one episode, three had two episodes. One patient had a high titer inhibitor against factor VIII. The hematoma was spontaneous and unilateral in all cases. The most common symptoms were hip pain and hip flexion contracture. Iliopsoas hematomas were confirmed by ultrasound, CT or MR scan. The treatment consisted of factor replacement and rehabilitation therapy. One patient needed erythrocytes transfusion. The mean duration of factor replacement therapy was 13.5 +/- 2.1 days. One severe hemophilia A patient with inhibitor treated with recombinant factor VIIa. Long term complications included paresthesia in 3 patients in the distribution of femoral nerve, quadriceps atrophy in 3 patients and permanent abnormal posture in one patient.Conclusion: The psoas muscles are located in the iliopsoas compartment posterior to the transversalis fascia, which is the posterior boundary of the retro peritoneum. Presentation of iliopsoas hematomas is often non-specific with abdominal, pelvic, back or groin pain or swelling. If they are large, iliopsoas hematomas can present with constipation, urinary frequency or fever. They can even compress the femoral nerve and cause a femoral neuropathy . A delay in treatment may result in permanent femoral nerve palsy (Mannucci N Engl J Med 2004). In this report, we present our experience and treatment modality in 14 episodes of iliopsoas hematoma in pediatric hemophilia patients. Rehabilitation treatment with factor replacement is safe and effective therapy for patients with small hematomas and little or no neurological symptoms. More aggressive recommendations have been made for patients with large hematomas and severe neurological symptoms or hemodynamic instability. An early diagnosis allows early factor replacement therapy, and decreases the risk of recurrence and morbidity. DisclosuresNo relevant conflicts of interest to declare.

Influence of immobilization mode on postoperative clinical data a month after an ACL reconstruction in athletes admitted to rehabilitation center

To determine the influence of immobilization mode on postoperative clinical data a month after an ACL reconstruction in athletes admitted to rehabilitation center. We analyzed post-operative data from a recorded cohort between 4 and 6 weeks after ACL ligamentoplasty. Were included patients with first ACL reconstruction on complete rupture in athlete came to the “Centre européen de rééducation du sportif” and aged at least 15 years 9 months. They follow a specialized rehabilitation protocol from 1st February 2008 to 30th October 2010. Clinical results were analyzed at hospital release between 4 and 6 weeks. The rehabilitation protocol was common to all patients. Clinical outcome parameters were quantitative (patella mobility, quadriceps atrophy, pain measurement by EVA, range of motion and scores: subjective IKDC and PPLP1) and qualitative (trophicity by measurement of the knee effusion and subquadricipital bursa flexibility, functional assessment quadriceps lock, walk evaluation). The patients were divided according to immobilization mode: orthosis articulated rigid or no brace. We have found no significant difference between each of three groups for each parameter studied ( P < 0.05). We do not have rupture in the three groups. There was not difference among the three groups for the qualitative and quantitative parameters, markers of decreasing inflammation and functional improvement at 4–6 week. In specialized center, orthosis establishment whatever the type or not put it, does not influence the early postoperative clinical results and evolution in patients with an ACL ligamentoplasty of the athlete. These results lead us to wonder about the value of the orthotics prescription, particularly articulated very expensive compared to simple rigid splints.

Atrophy of the Quadriceps Is Not Isolated to the Vastus Medialis Oblique in Individuals With Patellofemoral Pain

Cross-sectional. Objectives To determine if quadriceps atrophy was present in people with patellofemoral pain (PFP), and whether the vastus medialis oblique (VMO) was selectively involved. Despite the lack of research investigating individual quadriceps muscle size in individuals with PFP, it has been suggested that selective atrophy of the VMO relative to the vastus lateralis could be associated with PFP. The quadriceps muscle sizes of 35 participants with PFP (22 with unilateral and 13 with bilateral symptoms) and 35 asymptomatic control participants matched for age and sex were measured using real-time ultrasound. The thicknesses of the VMO, vastus lateralis, vastus medialis, rectus femoris, and vastus intermedius were measured. Paired-samples t tests were used to compare muscle thickness between limbs in those with unilateral PFP, and independent t tests were used to compare muscle thickness between groups with and without PFP. Results In those with unilateral PFP, the thickness of all portions of the quadriceps muscle was statistically smaller in the symptomatic compared to the asymptomatic limb: VMO (P = .038), vastus medialis (P<.001), vastus lateralis (P = .005), vastus intermedius (P = .013), and rectus femoris (P = .045). No difference was found in thickness of any of the portions of the quadriceps on the affected side of people with PFP compared to asymptomatic controls: VMO (P = .148), vastus medialis (P = .474), vastus lateralis (P = .122), vastus intermedius (P = .466), and rectus femoris (P = .508). Atrophy of all portions of the quadriceps muscles is present in the affected limb of people with unilateral PFP. There was no atrophy of the quadriceps in individuals with PFP compared to those without pathology. Selective atrophy of the VMO relative to the vastus lateralis was not identified in people with PFP.

Clinicopathologic features of sporadic inclusion body myositis in China

This study is to investigate the clinical and pathologic features of sporadic inclusion body myositis (sIBM) in China. We retrospectively evaluated the clinical and pathological features of consecutive patients in our department between January 1986 to May 2012. Total 28 cases of sIBM (20 males, 8 females, mean age was 56.93±8.79) were obtained by review of all 4099 muscle biopsy reports. The proportion of sIBM was 0.68% (28/4099) in China. Muscle weakness of quadriceps appeared 100% in 28 cases, while conspicuous atrophy of quadriceps appeared only in five cases (17.86%). Creatase values of 28 patients with sIBM were normal or mildly elevated. Muscle biopsies showed that atrophic fibers resembled more frequent in small angular and irregular shape (82.14%), less common in small round shape (17.86%). Rimmed vacuoles resembled crack (67.86%) and round (32.14%) shape. Mononuclear cell invasion into necrotic muscle fibers (35.71%) was more frequent than non-necrotic muscle fibers (7.14%). sIBM was still a rare disease in China compared to other countries. There were some certain specific pathological characteristics existed in Chinese sIBM patients.

Intermittent blood flow restriction does not reduce atrophy following anterior cruciate ligament reconstruction

BackgroundA previous study has reported a 50% reduction in disuse atrophy of the quadriceps during the first 14 days after anterior cruciate ligament (ACL) reconstruction. A follow-up trial is needed to confirm these promising results. The present study aims to investigate the effect of an occlusion stimulus on quadriceps atrophy after ACL reconstruction. MethodsA total of 24 subjects participated in the study. They were randomized into two groups. Starting the 2nd day after surgery, the occlusion group received an occlusion stimulus for 5 min, followed by removal of the occlusive pressure for 3 min. This was repeated five times in one training session, twice daily. During the period of occlusive stimulus, the subjects performed 20 low load exercises for the quadriceps. The control group followed the same exercise protocol, but without the occlusion stimulus. Changes in quadriceps anatomical cross section area (ACSA) were measured using axial magnetic resonance (MR) images at 40% and 50% of the length of the femur. ResultsBoth groups had a significant reduction of quadriceps ACSA from 2 days before surgery to 16 days after surgery. During the intervention period, the occlusion group lost 13.8% ± 1.1% (mean ± SEM) and the control group lost 13.1% ± 1.0% of their quadriceps ACSA, respectively. There was no significant difference between the occlusion and control groups with regards to atrophy of the quadriceps muscles. ConclusionIn conflict with other studies using a similar protocol, application of blood flow restriction the first 14 days after ACL reconstruction did not reduce quadriceps ACSA muscle atrophy measured by MR in a population of athletes.

Quadriceps muscle weakness and atrophy are associated with a differential epigenetic profile in advanced COPD.

Epigenetic mechanisms regulate muscle mass and function in models of muscle dysfunction and atrophy. We assessed whether quadriceps muscle weakness and atrophy are associated with a differential expression profile of epigenetic events in patients with advanced COPD (chronic obstructive pulmonary disease). In vastus lateralis (VL) of sedentary severe COPD patients (n=41), who were further subdivided into those with (n=25) and without (n=16) muscle weakness and healthy controls (n=19), expression of muscle-enriched miRNAs, histone acetyltransferases (HATs) and deacetylases (HDACs), growth and atrophy signalling markers, total protein and histone acetylation, transcription factors, small ubiquitin-related modifier (SUMO) ligases and muscle structure were explored. All subjects were clinically evaluated. Compared with controls, in VL of all COPD together and in muscle-weakness patients, expression of miR-1, miR-206 and miR-27a, levels of lysine-acetylated proteins and histones and acetylated histone 3 were increased, whereas expression of HDAC3, HDAC4, sirtuin-1 (SIRT-1), IGF-1 (insulin-like growth factor-1) were decreased, Akt (v-akt murine thymoma viral oncogene homologue 1) expression did not differ, follistatin expression was greater, whereas myostatin expression was lower, serum reponse factor (SRF) expression was increased and fibre size of fast-twitch fibres was significantly reduced. In VL of severe COPD patients with muscle weakness and atrophy, epigenetic events regulate muscle differentiation rather than proliferation and muscle growth and atrophy signalling, probably as feedback mechanisms to prevent those muscles from undergoing further atrophy. Lysine-hyperacetylation of histones may drive enhanced protein catabolism in those muscles. These findings may help design novel therapeutic strategies (enhancers of miRNAs promoting myogenesis and acetylation inhibitors) to selectively target muscle weakness and atrophy in severe COPD.

Contaminated open fracture and crush injury: a murine model.

Modern warfare has caused a large number of severe extremity injuries, many of which become infected. In more recent conflicts, a pattern of co-infection with Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus has emerged. We attempted to recreate this pattern in an animal model to evaluate the role of vascularity in contaminated open fractures. Historically, it has been observed that infected bones frequently appear hypovascular, but vascularity in association with bone infection has not been examined in animal models. Adult rats underwent femur fracture and muscle crush injury followed by stabilization and bacterial contamination with A. baumannii complex and methicillin-resistant Staphylococcus aureus. Vascularity and perfusion were assessed by microCT angiography and SPECT scanning, respectively, at 1, 2 and 4 weeks after injury. Quantitative bacterial cultures were also obtained. Multi-bacterial infections were successfully created, with methicillin-resistant S. aureus predominating. There was overall increase in blood flow to injured limbs that was markedly greater in bacteria-inoculated limbs. Vessel volume was greater in the infected group. Quadriceps atrophy was seen in both groups, but was greater in the infected group. In this animal model, infected open fractures had greater perfusion and vascularity than non-infected limbs.

The effects of the sagittal plane malpositioning of the patella and concomitant quadriceps hypotrophy on the patellofemoral joint: a finite element analysis.

Anterior knee pain is a common symptom after intramedullary nailing in tibia shaft fracture. Moreover, patellofemoral malalignment is also known to be a major reason for anterior knee pain. Patellofemoral malalignment predisposes to increased loading in patellar cartilage. In the previous study, we have demonstrated the quadriceps atrophy and patellofemoral malalignment after intramedullary nailing due to tibia shaft fracture. In this study, our aim was to clarify the effects of quadriceps atrophy and patellofemoral malalignment with the pathologic loading on the joint cartilage. Mesh models of patellofemoral joint were constructed with CT images and integrated with soft tissue components such as menisci and ligaments. Physiological and sagittal tilt models during extension and flexion at 15°, 30° and 60° were created generating eight models. All the models were applied with 137N force to present the effects of normal loading and 115.7N force for the simulation of quadriceps atrophy. Different degrees of loading were applied to evaluate the joint contact area and pressure value with the finite element analysis. There was increased patellofemoral contact area in patellar tilt models with respect to normal models. The similar loading patterns were diagnosed in all models at 0° and 15° knee flexion when 137N force was applied. Higher loading values were obtained at 30° and 60° knee flexions in sagittal tilt models. Furthermore, in the sagittal tilt models, in which the quadriceps atrophy was simulated, the loadings at 30° and 60° knee flexion were higher than in the physiological ones. Sagittal malalignment of the patellofemoral joint is a new concept that results in different loading patterns in the patellofemoral joint biomechanics. This malalignment in sagittal plane leads to increased loading values on the patellofemoral joint at 30° and 60° of the knee flexions. This new concept should be kept in mind during the course of diagnosis and treatment in patients with anterior knee pain. Definition of the exact biomechanical effects of the sagittal tilting will lead to the development of new treatment modalities.

A Randomized Controlled Trial of Angiotensin-Converting Enzyme Inhibition for Skeletal Muscle Dysfunction in COPD

BACKGROUND:Skeletal muscle impairment is a recognized complication of COPD, predicting mortality in severe disease. Increasing evidence implicates the renin-angiotensin system in control of muscle phenotype. We hypothesized that angiotensin-converting enzyme (ACE) inhibition would improve quadriceps function and exercise performance in COPD.METHODS:This double-blind, randomized placebo-controlled trial investigated the effect of the ACE inhibitor, fosinopril, on quadriceps function in patients with COPD with quadriceps weakness. Primary outcomes were change in quadriceps endurance and atrophy signaling at 3 months. Quadriceps maximum voluntary contraction (QMVC), mid-thigh CT scan of the cross-sectional area (MTCSA), and incremental shuttle walk distance (ISWD) were secondary outcomes.RESULTS:Eighty patients were enrolled (mean [SD], 65 [8] years, FEV1 43% [21%] predicted, 53% men). Sixty-seven patients (31 fosinopril, 36 placebo) completed the trial. The treatment group demonstrated a significant reduction in systolic BP (Δ−10.5 mm Hg; 95% CI, −19.9 to −1.1; P = .03) and serum ACE activity (Δ−20.4 IU/L; 95% CI, −31.0 to −9.8; P < .001) compared with placebo. No significant between-group differences were observed in the primary end points of quadriceps endurance half-time (Δ0.5 s; 95% CI, −13.3-14.3; P = .94) or atrogin-1 messenger RNA expression (Δ−0.03 arbitrary units; 95% CI, −0.32-0.26; P = .84). QMVC improved in both groups (fosinopril: Δ1.1 kg; 95% CI, 0.03-2.2; P = .045 vs placebo: Δ3.6 kg; 95% CI, 2.1-5.0; P < .0001) with a greater increase in the placebo arm (between-group, P = .009). No change was shown in the MTCSA (P = .09) or ISWD (P = .51).CONCLUSIONS:This randomized controlled trial found that ACE inhibition, using fosinopril for 3 months, did not improve quadriceps function or exercise performance in patients with COPD with quadriceps weakness.TRIAL REGISTRY:Current Controlled Trials; No.: ISRCTN05581879; URL: www.controlled-trials.com

Percutaneous reconstruction of patellar tendon using semitendinosus tendon in chronic patellar tendon injury — case series and outcome

BackgroundChronic patellar tendon injuries are rare. Patients with these debilitating injuries present with extension lag and quadriceps atrophy. Diagnosis is usually made on a clinical background. Various methods of reconstruction of torn patellar tendon have been described and the ideal method of treatment is a matter of debate. MethodsWe retrospectively reviewed the medical records of nine patients with chronic patellar tendon injury that came to us between June 2006 and July 2012. In all patients, the patellar tendon was reconstructed percutaneously using semitendinosus tendon. Picrusting of quadriceps was required in two patients to pull the patella down. ResultAverage follow-up was 4.5years. At final follow-up Lysholm score, Siwek and Rao grading were good to excellent in all patients, and at 12months, all patients showed quadriceps strength 80% or more of opposite quadriceps. ConclusionPercutaneous reconstruction of the patellar tendon in chronic patellar tendon injury using semitendinosus tendon gives excellent result. Picrusting of quadriceps along with lateral release may be required to pull the patella down. Level of evidenceLevel IV.

Differences in Neuromuscular Control and Quadriceps Morphology Between Potential Copers and Noncopers Following Anterior Cruciate Ligament Injury

Prospective cross-sectional study. To compare knee muscle morphology and voluntary neuromuscular control in individuals who sustained an anterior cruciate ligament (ACL) injury and were identified as being capable of avoiding surgery (potential copers) and those who were recommended for surgery (noncopers), within 6 months of injury. Quadriceps atrophy and poor neuromuscular control have been found in noncopers. However, the reasons why some noncopers may be able to avoid surgery remain elusive. Twenty participants (10 ACL-deficient noncopers and 10 ACL-deficient potential copers) were included in this study. Axial spin-echo, T1-weighted magnetic resonance imaging data of the lower extremities were captured. The volume and maximum cross-sectional area (CSA) of each muscle of the quadriceps and hamstrings were calculated following digital reconstruction. In addition, voluntary neuromuscular control was evaluated using an established target-matching task that required participants to produce static isometric loads across the knee joint. Electromyography was acquired from 5 muscles as participants performed the target-matching task. Circular statistics were used to calculate a specificity index to describe how well focused each muscle was activated toward its primary direction of muscle action. The ACL-deficient limb was then compared to the uninvolved limb of the noncopers and potential copers. The vasti (vastus medialis and vastus intermedius) of the involved limb of the noncopers were significantly smaller (P<.031) in comparison to those of their uninvolved limb. The potential copers' vastus lateralis maximum CSA (P = .047), total quadriceps muscle volume (P = .020) and maximum CSA (P = .015), and quadriceps-hamstring ratio volume (P = .021) and maximum CSA (P = .007) demonstrated quadriceps atrophy. However, only the ACL-deficient limb of the older (mean ± SD age, 27.4 ± 11.4 versus 19.9 ± 3.3 years; P = .032) and lower-activity-level (3.3 ± 0.5 versus 3.6 ± 0.5; P = .098) noncoper group demonstrated reduced rectus femoris (P = .057) and lateral hamstring (P = .064) neuromuscular control in comparison to their uninvolved limb. These findings suggest that quadriceps and hamstring muscle function, rather than muscle size, may be an important factor in the varied response early after ACL injury.

Diagnosis of Erdheim–Chester disease following the workup of multiple falls

the abdomen and limbs and massive weight loss. Physical examination noted a limited abduction of shoulders and irreducible flexion contracture of knees and elbows. Laboratory tests revealed eosinophilia at 1700 E/mm and hypergammaglobulinemia. A deep tissue biopsy noted a dermal thickening and fibrosis with perivascular nonspecific inflammatory infiltration, a fibrotic fascia with abundant infiltration by lymphocytes, plasma cells and numerous eosinophils. Muscular specimen shows no abnormalities. Magnetic resonance imaging showed fasciitis involving the different muscular compartments of the thigh predominant in the posterior compartment associated to muscular atrophy without significant anomalies of intra-muscular or subcutaneous fat signal intensity. Our two patients were treated with prednisone (1mg/kg/day) and physical therapy with insufficient response. Methotrexate was associated at 10 mg/week in addition to prolonged physical rehabilitation. The follow-upwasmarked by partial improvement of skin induration and joint stiffness. Case report 2: A 15 year old girl with a history of Hashimoto diseasewas seen for painless thickening of legs and forearms skinwith joint stiffness and proximalmuscular deficit. Physical examination noted also flexion contractures of the fingers and muscular atrophy of triceps and quadriceps. Laboratory testing revealed a peripheral eosinophilia at 1100 E/mm, hypergammaglobulinemia, anemia and inflammatory biologic syndrome. Muscular enzymes were at normal level. A deep tissue biopsy revealed subcutaneous nonspecific inflammatory infiltration with fibrosis of the derma. Muscular biopsy showed a nonspecificmyositis. Magnetic resonance imaging redescribed myositis involving pelvic muscles and fasciitis of the muscular lodges at the thigh backside. The evolution was characterized by a steroid's resistance indicating the association of methotrexate (12 mg per week). Conclusion: Eosinophilic fasciitis is an uncommon disease in childhood that must be considered in any patient with skin induration and painless joint contractures. The majority of patients are steroid responsive, but recourse to more aggressive treatment may be necessary. Interdisciplinary approach, including physical therapy, is crucial to prevent long-term morbidity.

Does Quadriceps Atrophy Exist in Individuals With Patellofemoral Pain? A Systematic Literature Review With Meta-analysis

Systematic literature review. To investigate whether quadriceps atrophy is present in the affected limb of individuals with patellofemoral pain (PFP). PFP is a common condition. Atrophy of the quadriceps femoris, in particular the vastus medialis obliquus, is often assumed to be present by clinicians, and its resolution may underpin the reported effectiveness of quadriceps strengthening intervention in PFP rehabilitation. A systematic search of the literature was conducted to identify studies that measured the size of the quadriceps in individuals with PFP. Meta-analyses were performed to determine whether quadriceps size in limbs with PFP differed from that in comparison limbs. Separate meta-analyses were performed for quadriceps size measured as girth and quadriceps size measured with imaging (thickness, cross-sectional area, and volume). Ten studies were included in this review. The meta-analysis of girth measurements (3 studies) found no atrophy in limbs with PFP (P = .638). The meta-analyses for imaging techniques (thickness, cross-sectional area, or volume measurements) showed atrophy in the limb with PFP compared to both the asymptomatic limb (3 studies) (P = .036) and limbs from a comparison group (3 studies) (P = .001). The single study that compared the vastus medialis obliquus and vastus lateralis in individuals with PFP found atrophy of both the vastus medialis obliquus and vastus lateralis but no significant difference in the amount of atrophy between them (P = .179). Quadriceps muscle atrophy was shown to be present in PFP when analyzed by imaging, but not by girth measures. Insufficient data were available to determine if there was greater atrophy of the vastus medialis obliquus than the vastus lateralis. These findings support the rationale for use of quadriceps strengthening as part of a rehabilitation program for PFP.

Quadriceps and Patellar Tendon Ruptures

The diagnosis of quadriceps and patellar tendon ruptures requires a high index of suspicion and thorough history-taking to assess for medical comorbidities that may predispose patients to tendon degeneration. Radiographic assessment with plain films supplemented by ultrasound and magnetic resonance imaging when the work-up is equivocal further aids diagnosis; however, advanced imaging is often unnecessary in patients with functional extensor mechanism deficits. Acute repair is preferred, and transpatellar bone tunnels serve as the primary form of fixation when the tendon rupture occurs at the patellar insertion, with or without augmentation depending on surgeon preference. Chronic tears and disruptions following total knee arthroplasty are special cases requiring reconstructions with allograft, synthetic mesh, or autograft. Rehabilitation protocols generally allow immediate weight-bearing with the knee locked in extension and crutch support. Limited arc motion is started early with active flexion and passive extension and then advanced progressively, followed by full active range of motion and strengthening. Complications are few but include quadriceps atrophy, knee stiffness, and rerupture. Outcomes are excellent if repair is done acutely, with poorer outcomes associated with delayed repair.

Gluteus maximus and soleus compensate for simulated quadriceps atrophy and activation failure during walking

Important activities of daily living, like walking and stair climbing, may be impaired by muscle weakness. In particular, quadriceps weakness is common in populations such as those with knee osteoarthritis (OA) and following ACL injury and may be a result of muscle atrophy or reduced voluntary muscle activation. While weak quadriceps have been strongly correlated with functional limitations in these populations, the important cause–effect relationships between abnormal lower extremity muscle function and patient function remain unknown. As a first step towards determining those relationships, the purpose of this study was to estimate changes in muscle forces and contributions to support and progression to maintain normal gait in response to two sources of quadriceps weakness: atrophy and activation failure. We used muscle-driven simulations to track normal gait kinematics in healthy subjects and applied simulated quadriceps weakness as atrophy and activation failure to evaluate compensation patterns associated with the individual sources of weakness. We found that the gluteus maximus and soleus muscles display the greatest ability to compensate for simulated quadriceps weakness. Also, by simulating two different causes of muscle weakness, this model suggested different compensation strategies by the lower extremity musculature in response to atrophy and activation deficits. Estimating the compensation strategies that are necessary to maintain normal gait will enable investigations of the role of muscle weakness in abnormal gait and inform potential rehabilitation strategies to improve such conditions.

Sustained Elevation of Circulating Growth and Differentiation Factor-15 and a Dynamic Imbalance in Mediators of Muscle Homeostasis Are Associated With the Development of Acute Muscle Wasting Following Cardiac Surgery*

Acute muscle wasting in the critically ill is common and causes significant morbidity. In a novel human model of acute muscle wasting following cardiac surgery, known or potential circulating modulators of muscle mass--insulin-like growth factor-1, myostatin, and growth and differentiation factor-15--were measured over a week. It was hypothesized that patients who developed acute muscle wasting would show distinct patterns of change in these mediators. A prospective longitudinal observational study of high-risk elective cardiac surgical patients identifying, by ultrasound, those developing muscle wasting. Tertiary cardiothoracic referral center: Royal Brompton Hospital, London, UK. Forty-two patients undergoing elective high-risk cardiothoracic surgery. Circulating insulin-like growth factor-1, myostatin, and growth and differentiation factor-15 were assayed preoperatively and over the first week postoperatively. The ability of growth and differentiation factor-15 to cause muscle wasting in vitro was determined in C2C12 myotubes. Of the 42 patients, 23 (55%) developed quadriceps atrophy. There was an acute decrease in insulin-like growth factor-1 and unexpectedly myostatin, known mediators of muscle hypertrophy and atrophy, respectively. By contrast, plasma growth and differentiation factor-15 concentrations increased in all patients. This increase in growth and differentiation factor-15 was sustained at day 7 in those who developed muscle wasting (day 7 compared with baseline, p<0.01), but recovered in the nonwasting group (p>0.05). Insulin-like growth factor-1 did not recover in those who developed muscle wasting (day 7 compared with baseline, p<0.01) but did in the nonwasting group (p>0.05). Finally, we demonstrated that growth and differentiation factor-15 caused atrophy of myotubes in vitro. These data support the hypothesis that acute muscle loss occurs as a result of an imbalance between drivers of muscle atrophy and hypertrophy. Growth and differentiation factor-15 is a potential novel factor associated with muscle atrophy, which may become a therapeutic target in patients with ICU acquired paresis and other forms of acute muscle wasting.