Proper elbow arthroscopy portal placement in pediatric and adolescent patients

We sought to evaluate proper elbow arthroscopy portal placement in pediatric and adolescent patients. Overall, 109 pediatric and adolescent patients who underwent elbow arthrography were included. Condylar width was measured and the proximal anterior joint capsule location was determined using the ulna-capsular distance. Condylar width and Bone mass index(BMI) also had a high positive correlation coefficient with the proximal joint capsule location. Proximal ulnar border is recommended new bony landmark in pediatric and adolescent patients who undergo elbow arthroscopy. In particular, condylar width and BMI were found to have a high positive correlation with the proximal joint capsule location.

What Is the Most Effective Eccentric Stretching Position in Lateral Elbow Tendinopathy?

Background

A variety of treatment options suggest that the optimal treatment strategy for lateral elbow tendinopathy (LET) is not known, and further research is needed to discover the most effective treatment for LET. The purpose of the present study was to verify the most effective position of eccentric stretching for the extensor carpi radialis brevis (ECRB) in vivo using ultrasonic shear wave elastography.

Methods

A total of 20 healthy males participated in this study. Resting position was defined as 90° elbow flexion and neutral position of the forearm and wrist. Elongation of the ECRB was measured for four stretching maneuvers (forearm supination/pronation and wrist extension/flexion) at two elbow angles (90° flexion and full extension). The shear elastic modulus, used as the index of muscle elongation, was computed using ultrasonic shear wave elastography for the eight aforementioned stretching maneuverangle combinations.

Results

The shear elastic modulus was the highest in elbow extension, forearm pronation, and wrist flexion. The shear elastic moduli of wrist flexion with any forearm and elbow position were significantly higher than the resting position. There was no significant difference associated with elbow and forearm positions except for elbow extension, forearm pronation, and wrist flexion positions.

Conclusions

This study determined that elbow extension, forearm pronation, and wrist flexion was the most effective eccentric stretching for the ECRB in vivo.

What are the anatomical predictive factors of degenerative superior labrum anterior to posterior lesion in rotator cuff tear?

The purpose of this study was to evaluate the influence of anatomical factors degenerative superior labrum anterior to posterior lesion in rotator cuff tear. The study included 421 middle-aged patients treated using arthroscopic surgery for rotator cuff tears. Patients were divided into two groups based on the superior labrum anterior-to-posterior (SLAP). Glenoid inclination, glenoid length, humeral head diameter, acromio-humeral distance (AHD) head-glenoid difference (HGD), head glenoid angle (HGA), size and retraction of rotator cuff tears were evaluated in both groups. In conclusion, a HGD exceeding 10 mm could be anatomically predictive of degenerative SLAP.

LEVEL OF EVIDENCE

Case series, Level IV.

Influence of Early Bisphosphonate Administration for Fracture Healing in Patients with Osteoporotic Proximal Humerus Fractures

BACKGROUND

Bisphosphonates are generally known to adversely affect fracture healing because they inhibit osteoclastic bone resorption. However, some authors argue that bisphosphonates have no adverse effect on the restoration of the mechanical integrity of long bones after fractures. It is unclear whether bisphosphonates can be initiated safely in patients with acute proximal humerus fractures. The aim of this study was to determine whether the early use of a bisphosphonate affects healing and outcomes of osteoporotic proximal humerus fractures treated with a locking compression plate.

METHODS

Between August 2004 and June 2013, a total of 82 osteoporotic patients who underwent locking plate fixation of proximal humerus fractures were enrolled retrospectively. The patients were divided into two groups according to the timing of the commencement of treatment with alendronate after surgery: group A (n = 34, initiation of the bisphosphonate treatment within two weeks after surgery) and group B (n = 48, control group, initiation of the treatment three months after surgery). Patients were assessed for radiographic union at 2, 6, 10, and 16 weeks, 6 months, and 1 year after surgery. Clinical assessments were performed using the Constant score and American Shoulder and Elbow Surgeons (ASES) score at 1 year after surgery.

RESULTS

No significant differences were observed between the two groups with respect to radiographic and clinical outcomes after locking plate fixation. All patients obtained fracture union, and the mean time to radiographic union was similar in group A and group B (6.3 and 6.6 weeks, respectively; p = 0.67).

CONCLUSIONS

This study shows that the early initiation of bisphosphonate treatment does not affect bone union or clinical outcomes in patients with an osteoporotic proximal humerus fracture treated by locking compression plate fixation.

Variations in fat mass contribution to bone mineral density by gender, age, and body mass index: the Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2011

The relationship of body composition and bone mineral density is complex and controversial. When classifying Korean population based on gender, age, and body mass index, fat mass had varying contributions to bone mineral density.

INTRODUCTION

The relationship between body composition and bone mineral density (BMD) is complex, and it is uncertain how components of body mass variably affect BMD.

METHODS

This cross-sectional observational study was performed in subjects ≥20 years based on the Korea National Health and Nutrition Examination Survey (KNHANES) 2008 to 2011. Among 17,583 subjects, the mean ages were 49.1 ± 16.0 years (M, n = 7495) and 49.3 ± 16.3 years (F, n = 10,088). Subjects were divided into age groups, either <50 or ≥50 years for males, or menopausal state, either premenopausal or postmenopausal, for females. A further classification used BMI, either <25 or ≥25 kg/m(2). Anthropometric and body composition parameters were compared and evaluated to look for correlations with BMD. Further, appendicular lean mass (ALM), fat mass (FM), fat percentage (FP), and waist circumference (WC) were included for multivariate analysis with BMD, controlling for covariates in each age group and BMI subgroup.

RESULTS

Anthropometric and body composition parameters significantly correlated with BMD in all age groups for both genders. After adjusting for covariates, ALM strongly affected BMD in all age groups for both genders. FM, FP, and WC significantly affected BMD in both age groups of women and in older men, but they did not affect BMD in younger men. Fat indices positively affected BMD of all sites in all non-obese women and in non-obese older men. However, little contribution was found in obese subgroups of both genders and in non-obese younger men.

CONCLUSION

Considering different weights of covariates, ALM strongly contributed to BMD in all gender, age, and BMI groups. On the other hand, fat indices positively affected BMD of both age groups in women and older men with normal BMI, but they showed little contribution to BMD within the same age groups with high BMI or any BMI subgroups of younger men.

Clinical results of an arthroscopic modified Brostrom operation with and without an internal brace

Background

The concept of utilizing nonabsorbable suture tape fixed directly to bone to augment Brostrom repairs of the anterior talofibular ligament (ATFL) has been proposed. However, no clinical data are currently available regarding the arthroscopic modified Brostrom operation with an internal brace.

Materials and methods

This study involved 85 consecutive patients (22 in the with internal brace group; 63 in the without internal brace group) who could be followed up for >6 months after undergoing an arthroscopic modified Brostrom operation. The American Orthopaedic Foot & Ankle Society (AOFAS) score was administered to assess the functional status. At preoperation and at 24 weeks after surgery, the anterior drawer test was examined clinically.

Results

Improvement of mean AOFAS score in the internal brace group from before surgery to two weeks after surgery was statistically significant (p < 0.05). At 24-week follow-up, the anterior drawer test showed grade 0 laxity in 19 patients (86.4 %) and grade 1 in three patients (13.6 %). Improvement of AOFAS score in the group without an internal brace from before surgery to 6 weeks after surgery was not statistically significant (p = 0.001). At 24-week follow-up, the anterior drawer test showed grade 0 laxity in 54 patients (85.7 %) and grade 1 in nine patients (14.3 %).

Conclusion

Patients in the internal brace group were able to quickly return to activity and sports. We believe this technique could be a viable option for surgically treating chronic lateral ankle instability in patients who need an early return to activity and sports.

Level of evidence

III.

Measurements of Elliptic and Triangular Flow in High-Multiplicity 3He+Au Collisions at √(s(NN))=200 GeV

We present the first measurement of elliptic (v(2)) and triangular (v(3)) flow in high-multiplicity (3)He+Au collisions at √(s(NN))=200  GeV. Two-particle correlations, where the particles have a large separation in pseudorapidity, are compared in (3)He+Au and in p+p collisions and indicate that collective effects dominate the second and third Fourier components for the correlations observed in the (3)He+Au system. The collective behavior is quantified in terms of elliptic v(2) and triangular v(3) anisotropy coefficients measured with respect to their corresponding event planes. The v(2) values are comparable to those previously measured in d+Au collisions at the same nucleon-nucleon center-of-mass energy. Comparisons with various theoretical predictions are made, including to models where the hot spots created by the impact of the three (3)He nucleons on the Au nucleus expand hydrodynamically to generate the triangular flow. The agreement of these models with data may indicate the formation of low-viscosity quark-gluon plasma even in these small collision systems.

Measurement of Long-Range Angular Correlation and Quadrupole Anisotropy of Pions and (Anti)Protons in Central d+Au Collisions at sqrt[s_{NN}]=200 GeV

We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sqrt[s_{NN}]=200 GeV. The charged hadron is measured at midrapidity |η|<0.35, and the energy is measured at large rapidity (-3.7<η<-3.1, Au-going direction). An enhanced near-side angular correlation across |Δη|>2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v_{2} for inclusive charged hadrons at midrapidity up to p_{T}=4.5 GeV/c. We also present the measurement of v_{2} for identified π^{±} and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sqrt[s_{NN}]=5.02 TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.

Correlation of clinical symptoms and function with fatty degeneration of infraspinatus in rotator cuff tear

PURPOSE

The aim of this study was to analyse the correlation of clinical symptoms and function with the fatty degeneration of the infraspinatus in rotator cuff tears.

METHODS

A total of 152 patients who had rotator cuff tears was enroled retrospectively. The infraspinatus muscle was divided into two compartments according to the bundle of fibres, and the patients were divided into four groups that reflected fatty degeneration. The muscle strength of the shoulder and clinical symptoms was investigated.

RESULTS

The severity of the rotator cuff tear and retraction increased with fatty degeneration of both the superior and inferior parts in the infraspinatus muscles. Because of the increasing fatty degeneration of the superior part of the infraspinatus, the shoulder strength index (SSI) of abduction had poor results. Additionally, as the fatty degeneration of the inferior part of the infraspinatus increased, the SSI of abduction and external rotation had worse results.

CONCLUSIONS

Fatty degeneration of the superior part of the infraspinatus has no correlation with the power of external rotation but has a negative correlation with the power of abduction. Moreover, fatty degeneration of the inferior part of the infraspinatus has a negative correlation with both the power of abduction and external rotation.

LEVEL OF EVIDENCE

Retrospective study, Level IV.

Baker's Cyst Filled with Hematoma at the Lower Calf

Baker's cyst is a distension of the gastrocnemius-semimembranosus bursa of the knee, which communicates with the posterior portion of the joint capsule. Baker's cyst is commonly located in the inferomedial or superficial layers of the knee joint and rarely extends laterally or proximally. Complications of Baker's cysts are dissection, rupture, pseudothrombophlebitis, leg ischemia, nerve entrapment, and compartment syndrome. However, hematomas in the Baker's cyst have not been reported in Korea. We report a rare case of hematoma in the Baker's cyst with subfascial extension into the calf. The hematoma was demonstrated by magnetic resonance imaging and removed by mass excision.

Paraspinal muscle changes of unilateral multilevel minimally invasive transforaminal interbody fusion

PURPOSE

We attempted to identify changes in back muscle atrophy occurring in multilevel minimally invasive transforaminal interbody fusion (MITLIF) and the impact of these changes on clinical outcomes.

METHODS

This study was conducted on 92 patients who underwent unilateral MITLIF between 2006 and 2013, had been tracked with a follow-up for at least 1 year, and had been assessed by pre- and postoperative computed tomography (CT). For the clinical evaluation, a pre- and postoperative visualized analog scale (VAS) of the back and legs, and Oswestry Disability Index (ODI) were measured. CT was used for the evaluation of back muscle atrophy and a cross-sectional area (CSA) of the multifidus was measured at the level below a fused segment, excluding metal artifacts.

RESULTS

There was no significant difference in the reduction of CSA between groups with one-, two-, or three-plus-segment fusion. In addition, no statistically significant differences were found in the pre- and postoperative VAS of the back, VAS of the legs, and ODI between the three groups. The reduction of CSA showed a statistically significant positive correlation with preoperative VAS of the back (p = 0.025, r = 0.562). On the other hand, no significant difference was found in VAS of the leg (p = 0.437, r = 0.082) and ODI (p = 0.106, r = 0.017).

CONCLUSION

When performing unilateral multilevel MITLIF, significant difference was not found in the atrophy of the multifidus according to the number of fused segments. The clinical outcomes also showed no significant difference. Therefore, unilateral MITLIF can be considered to be an effective surgical method to minimize lumbar muscle damage, even at multiple levels.

Sonoelastography findings of supraspinatus tendon in rotator cuff tendinopathy without tear: comparison with magnetic resonance images and conventional ultrasonography

BACKGROUND AND PURPOSE

Sonoelastography (SE) is a new technique that can assess differences in tissue stiffness. This study investigated the performance of SE for the differentiation of supraspinatus (SSP) tendon alterations of tendinopathy compared to magnetic resonance imaging (MRI) and conventional ultrasonography (US).

METHODS

One hundred and eighteen consecutively registered patients with symptoms and MRI findings of SSP tendinopathy were assessed with US and SE. Coronal images of the SSP tendon were obtained using US and SE. Increased signal intensity on T2-weighted images in the coronal planes were graded according to the extent of the signal changes from ventral to dorsal. SE images were evaluated by reviewers using an experimentally proven color grading system.

RESULTS

Using SE, 7.6 % of the SSP tendons were categorized as grade 0, 30.5 % as grade 1, 19.5 % as grade 2, and 42.4 % as grade 3. Evaluation of the interobserver reliability of the SE findings showed "almost perfect agreement", with a weighted kappa coefficient of 0.83. By comparing the MRI findings with the SE findings, grades of MRI and SE had a positive correlation (r = 0.829, p = <0.001). Furthermore, grades of US and SE also had a positive correlation (r = 0.723, p = <0.001).

CONCLUSIONS

SE is valuable in the detection of the intratendinous and peritendinous alterations of the SSP tendon and has excellent interobserver reliability and excellent correlation with MRI findings and conventional ultrasonography findings.

Usefulness of Contralateral Indirect Decompression through Minimally Invasive Unilateral Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

Retrospective study.

PURPOSE

This study aims to investigate the clinical and radiological results of contralateral indirect decompression through minimally invasive unilateral transforaminal lumbar interbody fusion (MI-TLIF).

OVERVIEW OF LITERATURE

Several studies have proposed that blood loss and operation time could be reduced through a unilateral approach, although many surgeons have forecast that satisfactory foraminal decompression is difficult to achieve through a unilateral approach.

METHODS

The study included 30 subjects who had undergone single-level MI-TLIF. Visual analogue scale (VAS) and Oswestry disability index (ODI) were analyzed for clinical assessment. Disc height, segmental lordosis, and lumbar lordosis angle were examined for radiological assessment. The degree of contralateral indirect decompression was evaluated through a comparative analysis, with a magnetic resonance imaging (MRI) performed preoperatively and at one year postoperatively.

RESULTS

Intraoperative blood loss volume was 308.75 mL in the unilateral approach group (UAP), and 575.00 mL in the bilateral approach group (BAP), showing a statistically significant difference. Operation time was 139.50 minutes in the UAP group, and 189.00 minutes in the BAP group, exhibiting a statistically significant difference (p<0.05). On the other hand, no significant difference was found in VAS, ODI, disc height, lordosis angles and the degree of nerve decompression in the vertebral foramen, using MRI, between the two groups (p>0.05).

CONCLUSIONS

Satisfactory results were acquired with MI-TLIF conducted through the unilateral approach of contralateral indirect decompression, in alignment with the bilateral approach. Therefore, contralateral indirect decompression is thought to be a useful procedure in reducing the operation time and volume of blood loss.

Cold-nuclear-matter effects on heavy-quark production at forward and backward rapidity in d + Au collisions at √sNN = 200 GeV

The PHENIX experiment has measured open heavy-flavor production via semileptonic decay over the transverse momentum range 1 < p(T) < 6  GeV/c at forward and backward rapidity (1.4 < |y| < 2.0) in d+Au and p + p collisions at √sNN = 200  GeV. In central d+Au collisions, relative to the yield in p + p collisions scaled by the number of binary nucleon-nucleon collisions, a suppression is observed at forward rapidity (in the d-going direction) and an enhancement at backward rapidity (in the Au-going direction). Predictions using nuclear-modified-parton-distribution functions, even with additional nuclear-p(T) broadening, cannot simultaneously reproduce the data at both rapidity ranges, which implies that these models are incomplete and suggests the possible importance of final-state interactions in the asymmetric d + Au collision system. These results can be used to probe cold-nuclear-matter effects, which may significantly affect heavy-quark production, in addition to helping constrain the magnitude of charmonia-breakup effects in nuclear matter.

Deformity correction by femoral supracondylar dome osteotomy with retrograde intramedullary nailing in varus deformity of the distal femur after pathologic fracture of giant cell tumor

Angular deformities of the distal femur occur in congenital diseases or due to acquired causes, such as malunion after a fracture of the distal femur. Angular deformities of the lower extremities affect the mechanical axis, causing changes in the weight pressure on the articular surface. As a result, angular deformities quicken the progression of osteoarthritis. Therefore, correction of deformities should be performed to prevent the progression of osteoarthritis. Distal femoral osteotomy is one of the methods to correct angular deformities in unicompartmental osteoarthritis. However, femoral supracondylar dome osteotomy with retrograde intramedullary nailing in the distal femur with a varus deformity has been rarely reported. Herein, we describe a technique for femoral supracondylar dome osteotomy with retrograde intramedullary nailing in a varus deformity after a pathologic fracture of giant cell tumor in the distal femur with a review of the relevant literature.

The clinical and radiological outcomes of multilevel minimally invasive transforaminal lumbar interbody fusion

PURPOSE

To investigate the clinical and radiological outcomes of multilevel minimally invasive transforaminal lumbar interbody fusion (MITLIF) in multilevel degenerative lumbar diseases.

METHODS

Of 172 patients who could be followed-up for at least 1 year after undergoing a MITLIF, a total of 127 patients in whom unilateral cages were used through a unilateral approach (consisting of 69 patients for single-level, 40 for two-level, and 18 for three- or higher-level) were retrospectively studied as subjects. In this study, clinical assessment parameters included Visual Analog Scale (VAS) score and Oswestry Disability Index (ODI), while radiologic assessment parameters included disc height, segmental lordotic angle, and lumbar lordotic angle. At the last follow-up, the level of bone fusion was determined in accordance with the Brantigan and Steffee criteria for classification of fusion results.

RESULTS

The VAS scores of back pain and radiating leg pain tended to improve postoperatively, and showed no significant difference among groups (p > 0.05). In terms of ODI, the results of functional assessments also indicated no significant difference among groups (p > 0.05). Similarly, there was no statistically significant difference in disc height, segmental lordotic angle, lumbar lordotic angle, and bone fusion depending on the number of fusion levels (p > 0.05).

CONCLUSIONS

Regardless of the number of fused levels, satisfactory clinical and radiological outcomes of MITLIF were seen in patients with spinal stenosis, which suggests that the said surgical procedure may be useful even for patients with multilevel spinal stenosis.

Cross section and parity-violating spin asymmetries of W± boson production in polarized p + p collisions at sqrt[s] = 500 GeV

Large parity-violating longitudinal single-spin asymmetries A(L)(e+) = -0.86(-0.14) (+0.30) and A(L)(e-) = 0.88(-0.71) (+0.12) are observed for inclusive high transverse momentum electrons and positrons in polarized p+p collisions at a center-of-mass energy of sqrt[s] = 500 GeV with the PHENIX detector at RHIC. These e± come mainly from the decay of W± and Z0 bosons, and their asymmetries directly demonstrate parity violation in the couplings of the W± to the light quarks. The observed electron and positron yields were used to estimate W± boson production cross sections for the e± channels of σ(pp → W+ X) × BR(W+ → e+ ν(e)) = 144.1 ± 21.2(stat)(-10.3) (+3.4) (syst) ± 21.6(norm)  pb, and σ(pp → W- X) × BR(W- → e- ν[over ¯](e)) = 31.7 ± 12.1(stat)(-8.2) (+10.1) (syst) ± 4.8(norm)  pb.

Effect of dietary fermented garlic by Weissella koreensis powder on growth performance, blood characteristics, and immune response of growing pigs challenged with Escherichia coli lipopolysaccharide

Two experiments were conducted to investigate the effect of fermented garlic by Weissella koreensis powder (WKG) on pig growth performance and immune responses after an Escherichia coli lipopolysaccharide (LPS) challenge. In Exp. 1, 120 growing barrows (23.5 ± 0.5 kg of BW and 56 d of age) were used in a 35-d experiment to determine the optimal amounts of WKG. Pigs were randomly allotted to 1 of 5 treatments with 6 replicate pens and 4 pigs per pen. Dietary treatments included 1) NC (negative control; basal diet without antibiotics), 2) PC (positive control; basal diet + 1 g of tylosin/kg), 3) WKG1 (basal diet + 1 g of WKG/kg), 4) WKG2 (basal diet + 2 g of WKG/kg), and 5) basal diet + 4 g of WKG/kg. At the end of the feeding period, 12 pigs each were selected from the NC and WKG2 treatment groups, and 6 pigs were injected with LPS (50 μg/kg of BW) and the other 6 pigs with an equivalent amount of sterile saline, resulting in a 2 × 2 factorial arrangement of treatments. Blood samples and rectal temperature data were collected at 0, 2, 4, 6, 8, and 12 h after challenge. The ADG of pigs fed WKG- and antibiotic-supplemented diets was greater (P<0.05) than NC from d 14 to 35 and the overall phase, but no dosage-dependent effects were observed. At the end of the experiment, the fecal E. coli count was linearly reduced by the increasing amounts of WKG at d 35 (P=0.01). Challenge with LPS increased white blood cell counts at 6 and 8 h (P<0.01) and depressed lymphocyte concentration at 4, 8, and 12 h (P<0.01). During challenge, LPS injection increased rectal temperature at 2, 4, 6, and 8 h postchallenge (P<0.05), and WKG2 alleviated (P<0.05) the increase in the temperature at 2 h postchallenge. The LPS injection increased plasma tumor necrosis factor-α and IGF-1 concentrations at 2, 4, 6, 8, and 12 h (P<0.01), whereas an alleviating effect of WKG was observed at 4, 6, and 8 h after LPS challenge (P<0.05). At 2, 4, and 6 h postchallenge, concentration of cluster of differentiation-antigen-4-positive cells and cluster of differentiation-antigen-8-positive cells (CD4(+) and CD8(+), respectively) increased in the LPS treatments (P<0.05), and the WKG2 boosted this effect (P<0.05). In conclusion, dietary supplementation of WKG2 in growing pigs can improve ADG and have a beneficial effect on the immune response during an inflammatory challenge.

Osteoradionecrosis of the hyoid bone: imaging findings

BACKGROUND AND PURPOSE

ORN is a postradiation complication that has been well-documented in the medical literature. Most cases in the head and neck have been described in the mandible or larynx. Only a handful of cases in the hyoid bone are documented, all in the clinical literature. Our purpose is to present the clinical and imaging features of ORN involving the hyoid bone.

MATERIALS AND METHODS

We present a case series of 13 patients with imaging findings highly suggestive of hyoid ORN after radiation therapy for head and neck cancers, in which we observed progressive features of hyoid disruption along with adjacent soft-tissue ulceration.

RESULTS

Pretreatment imaging, when available, showed a normal hyoid. Typical postradiation imaging findings included an initial tongue base ulcerative lesion with air approaching the hyoid bone, and subsequent observation of hyoid fragmentation, often with intraosseous or peri-hyoid air and the absence of associated mass-like enhancement.

CONCLUSIONS

Findings of hyoid fragmentation, cortical disruption, and soft tissue or intraosseous air in the postradiation therapy patient should strongly suggest the diagnosis of hyoid ORN. It is important recognize this entity because the diagnosis may preclude potentially harmful diagnostic intervention and allow more appropriate therapy.

The effect of mosapride (5HT-4 receptor agonist) on insulin sensitivity and GLUT4 translocation

AIMS

We investigated the effect of mosapride, 5HT-4 (5-hydroxytryptamine) agonist, on blood glucose level and insulin sensitivity in subjects with impaired glucose tolerance (IGT) and conducted an in vitro study to evaluate the action mechanism.

METHODS

Thirty IGT patients were randomly assigned to receive either mosapride or placebo for 2 weeks. Biochemical profiles and insulin sensitivity index from euglycemic hyperinsulinemic clamp test were assessed before and after treatment. In cultured myotubes from human skeletal muscle cells, insulin- and mosapride-induced GLUT4 translocation and tyrosine phosphorylation of IRS-1 were determined.

RESULTS

After 2 weeks of treatment with mosapride, glucose disposal rates were significantly increased up to those of control (mosapride 5.47+/-1.72 vs 7.06+/-2.13, P=0.004, placebo 5.42+/-1.85 vs 5.23+/-1.53mgkg(-1)min(-1)). Fasting plasma glucose (FPG) and insulin levels were decreased. Mosapride increased the contents of GLUT4 in plasma membrane representing the increased recruitment of glucose transporters from intracellular pool. While insulin treatment on human skeletal muscle cell resulted in an increased tyrosine phosphorylation of IRS-1, mosapride did not have any effect.

CONCLUSIONS

Mosapride is effective in decreasing FPG without stimulating insulin secretion in IGT subjects, possibly by inducing GLUT4 translocation in skeletal muscles.