Inhibitory Regulation of FOXO1 in PPARδ Expression Drives Mitochondrial Dysfunction and Insulin Resistance.

Forkhead box O1 (FOXO1) regulates muscle growth, but the metabolic role of FOXO1 in skeletal muscle and its mechanisms remain unclear. To explore the metabolic role of FOXO1 in skeletal muscle, we generated skeletal muscle-specific Foxo1 inducible knockout (mFOXO1 iKO) mice and fed them a high-fat diet to induce obesity. We measured insulin sensitivity, fatty acid oxidation, mitochondrial function, and exercise capacity in obese mFOXO1 iKO mice and assessed the correlation between FOXO1 and mitochondria-related protein in the skeletal muscle of patients with diabetes.

Does the proximal humeral bone quality influence alignment after reverse total shoulder arthroplasty with short humeral stems?

Purpose: When compared to standard-length humeral stem in reverse total shoulder arthroplasty (RTSA), short humeral stems in RTSA require good proximal humeral metaphyseal bone quality to gain proper and secure fixation during prosthetic implantation. Shorter humeral stems potentially carry more risk of misalignment than standard or long humeral stems. The hypothesis was that misalignment of the short humeral stems is influenced by regional bone quality.

Flexion-extension-supination test compared to arthroscopic findings of biceps long head pathology: A physical examination that reflect anatomical evolution of human shoulder girdle.

The accuracy of physical examination for diagnosing lesions of the long head of the biceps tendon (LHBT) remains unsatisfactory. The purpose of this study was to describe a new diagnostic test, the Flexion-Extension-Supination (FES) test for diagnosing lesions of the long head of biceps tendon. A prospective study of 162 patients was performed to evaluate the diagnostic value of FES test.

Does stress shielding after radial head arthroplasty affect functional outcomes?

Background: Various complications related to the prosthesis, such as implant loosening and stress shielding phenomenon, could develop after prosthetic replacement of the radial head. Stress shielding is known to occur around rigidly fixed implants. The purpose of this study was to evaluate the clinical influence and causative factors of the stress shielding phenomenon after radial head arthroplasty (RHA).

Vertical Interfragmentary Doubled Suture for Displaced Patella Fractures: Sequential Compressive Tightening with Nice Knot.

In the treatment of displaced patella fractures, open reduction and internal fixation is essential for patellofemoral congruency and restoration of the knee extension mechanism. Various surgical techniques and materials can be used, and their clinical outcomes are favorable. However, soft-tissue and skin irritation, pain, and limited range of motion due to metallic hardware can occur, and removal of hardware such as screws and K-wire may be required after bony union.

Posteromedial Elbow Dislocations without Relevant Osseous Lesions: Clinical Characteristics, Soft-Tissue Injury Patterns, Treatments, and Outcomes.

Background: Although simple posterolateral or posterior elbow dislocations are relatively common and usually stable after closed reduction, simple posteromedial dislocations are extremely rare and poorly characterized. We investigated the clinical characteristics, soft-tissue injury patterns, treatments, and outcomes of a series of posteromedial elbow dislocations without relevant osseous lesions.

Methods: We retrospectively reviewed 20 cases of simple posteromedial elbow dislocations without relevant osseous lesions that were treated at 7 fellowship training hospitals during a 10-year period.

Supplementary Technique for Unstable Clavicle Shaft Fractures: Interfragmentary Wiring and Temporary Axial K-Wire Pinning.

Background: Treatment of unstable clavicle fractures remains a challenge for orthopedic surgeons, but the evolution of treatment strategies has allowed for reliable results with minimal complications. Although several surgical options exist, open reduction with plating remains the treatment of choice for clavicle fractures. The purpose of this study is to determine an easy way to achieve successful preplating reduction while minimizing surrounding soft tissue damage during treatment of midshaft fractures of the clavicle.

Pathologic Femoral Neck Fracture Due to Fanconi Syndrome Induced by Adefovir Dipivoxil Therapy for Hepatitis B.

In Fanconi syndrome, hypophosphatemic osteomalacia is caused by proximal renal tubule dysfunction which leads to impaired reabsorption of amino acids, glucose, urate, and phosphate. We present a rare case of a 43-year-old Korean male who was found to have insufficiency stress fracture of the femoral neck secondary to osteomalacia due to Fanconi syndrome. He had been receiving low-dose adefovir dipivoxil (ADV, 10 mg/day) for the treatment of chronic hepatitis B virus infection for 7 years and he subsequently developed severe hypophosphatemia and proximal renal tubule dysfunction.

TLR2 deficiency attenuates skeletal muscle atrophy in mice.

Oxidative stress and inflammation are associated with skeletal muscle atrophy. Because the activation of toll-like receptor (TLR) 2 induces oxidative stress and inflammation, TLR2 may be directly linked to skeletal muscle atrophy. This study examined the role of TLR2 in skeletal muscle atrophy in wild-type (WT) and TLR2 knockout (KO) mice.

Treatment of thoracolumbar fracture.

The most common fractures of the spine are associated with the thoracolumbar junction. The goals of treatment of thoracolumbar fracture are leading to early mobilization and rehabilitation by restoring mechanical stability of fracture and inducing neurologic recovery, thereby enabling patients to return to the workplace. However, it is still debatable about the treatment methods.

Salmonella osteomyelitis of the femoral diaphysis in a healthy individual.

In reviewing the literature, we found few cases of Salmonella osteomyelitis of the femoral diaphysis in a healthy patient. Most are typically associated with sickle cell anemia or immunosuppressed patients. We report on the successful treatment of Salmonella osteomyelitis in the mid-diaphyseal region of the femur caused by Salmonella species in a healthy individual.

Reliability of the classification and treatment of dislocations of the acromioclavicular joint.

Background: We evaluated interobserver and intraobserver reliability of the classification and treatment of acromioclavicular (AC) joint dislocations and assessed the impact of adding 3-dimensional computed tomography (3D CT) on the reliability of classification and treatment choice.

Methods: Ten surgeons independently reviewed plain radiographs and 3D CT in 28 cases with AC joint dislocation. Images from each case were randomly presented to the observers, with plain radiographs alone being presented first, followed by plain radiographs plus 3D CT 2 weeks later.

Hemin, heme oxygenase-1 inducer, attenuates immobilization-induced skeletal muscle atrophy in mice.

Aims: The present study examined the effect of the heme oxygenase (HO)-1 inducer hemin on skeletal muscle atrophy induced by single limb immobilization in mice.

Main Methods: Immobilization was conducted in the left hindlimb of C57BL/6 mice for 1 week and the right hindlimb was used as a control. Hemin (30 mg/kg) was administered intraperitoneally once a day during the immobilization period.

The association between meniscal subluxation and cartilage degeneration.

Purpose: The menisci play a critical protective role for the knee joint through shock absorption and load distribution. We hypothesized that cartilage degeneration will be abruptly progressed if meniscal subluxation exceeds a critical point.

Methods: Of 56 cases that showed medial meniscal subluxation without cartilage degeneration of ipsilateral medial femoral condyle (MFC) on initial MRI, from January 2005 to June 2007, meniscal subluxation index (MSI), the ratio of meniscal overhang to meniscal width in mid-coronal image of initial MRI, was measured.

Simultaneous bilateral quadriceps tendon rupture in patient with chronic renal failure.

Simultaneous bilateral spontaneous rupture of the quadriceps tendon is a very rare condition and only a few cases have been reported in the literature. The etiology is not clear yet. But it occurs infrequently in patients with chronic metabolic disorders.

Deficiency of inducible nitric oxide synthase attenuates immobilization-induced skeletal muscle atrophy in mice.

The present study examined the effects of inducible nitric oxide synthase (iNOS) deficiency on skeletal muscle atrophy in single leg-immobilized iNOS knockout (KO) and wild-type (WT) mice. The left leg was immobilized for 1 wk, and the right leg was used as the control. Muscle weight and contraction-stimulated glucose uptake were reduced by immobilization in WT mice, which was accompanied with increased iNOS expression in skeletal muscle.

Inhibition of Inducible Nitric Oxide Synthase Attenuates Monosodium Urate-induced Inflammation in Mice.

The present study elucidated the effect of the selective inducible nitric oxide synthase (iNOS) inhibitor N(6)-(1-iminoethyl)-L-lysine (L-NIL) on monosodium urate (MSU) crystal-induced inflammation and edema in mice feet. L-NIL (5 or 10 mg/kg/day) was administered intraperitoneally 4 h before injection of MSU (4 mg) into the soles of mice hindlimb feet. Twenty-four hours after MSU injection, foot thickness was increased by 160% and L-NIL pretreatment reduced food pad swelling in a dose dependent manner.

Deficiency of iNOS Does Not Prevent Isoproterenol-induced Cardiac Hypertrophy in Mice.

We investigated whether deficiency of inducible nitric oxide synthase (iNOS) could prevent isoproterenol-induced cardiac hypertrophy in iNOS knockout (KO) mice. Isoproterenol was continuously infused subcutaneously (15 mg/kg/day) using an osmotic minipump. Isoproterenol reduced body weight and fat mass in both iNOS KO and wild-type mice compared with saline-infused wild-type mice.

Inhibition of lipid infusion-induced skeletal muscle insulin resistance by cotreatment with tempol and glutathione in mice.

In the present study, we examined whether lipid infusion-induced insulin resistance in skeletal muscle could be reversed by the antioxidants tempol, glutathione (GSH), or tempol with GSH in male C57BL/6J mice via hyperinsulinemic-euglycemic clamp. Lipid infusion increased the mRNA level of mitochondrial type superoxide dismutase (Mn-SOD), glutathione peroxidase 1, tumor necrosis factor-alpha, and interleukin-6. Lipid infusion decreased GSH and GSH/glutathione disulfide (GSSG) ratio and increased the activities of JNK and p38 in skeletal muscle.

AMPK activator, AICAR, inhibits palmitate-induced apoptosis in osteoblast.

Osteoblast apoptosis reduces bone mineral density. Apoptosis can be induced in a variety of cells by palmitate, which is one of the most common saturated fatty acids in dietary fat. The AMPK activator, AICAR, has been shown to inhibit palmitate-induced apoptosis.