Effect of neuromuscular control on the shoulder function of patients with healed rotator cuff and those with retear after arthroscopic rotator cuff repair.

Purpose: To compare functional outcomes such as muscle strength, neuromuscular control and patient-reported outcomes (PROs) between patients with healed rotator cuffs and those with retears after arthroscopic rotator cuff repair (RCR).

Methods: One hundred and nine patients who underwent arthroscopic RCR were included (85 in the healed group, 24 in the retear group). Shoulder muscle strength and neuromuscular control index (acceleration time [AT]) were evaluated using an isokinetic device.

Innovative approach of nanopore-based metagenomic sequencing for rapid identification of bacterial pathogens in joint fluid: A pilot study.

Analysis of 11 clinical samples of joint fluid in this pilot study demonstrated proof-of-concept for nanopore-based metagenomic sequencing to serve as a complementary real-time diagnostic technique for septic arthritis, with a sensitivity of 75.0 % and specificity of 57.1 %, compared to the gold standard method of bacterial culture.

Effects of humeral head stabilization intervention during aggressive manual passive stretching exercises in patients with painful stiff shoulder: a prospective, comparative study.

Background: No reports have been published verifying the effects of manual interventions such as humeral head stabilization on improving function and reducing pain when applying aggressive manual passive stretching in patients with painful stiff shoulders. The purpose of this study was to compare clinical outcomes, such as range of motion, pain, and disability scores, in patients with painful stiff shoulders with and without humeral head stabilization intervention while applying aggressive manual passive stretching.

Methods: Fifty-six patients with painful stiff shoulders were recruited (31 with humeral head stabilization intervention and 25 without such intervention).

Intravenous Tranexamic Acid Improves Visual Clarity During Synovectomy in Patients Undergoing Arthroscopic Rotator Cuff Repair: A Double-Blind, Randomized Controlled Study.

Purpose: To assess the effects of intravenous tranexamic acid (TXA) on visual clarity at various surgical stages and the correlation between the severity of synovitis and bursitis and the grade of visual clarity in patients undergoing arthroscopic shoulder surgery under an interscalene brachial plexus block.

Methods: This double-blind, randomized controlled study included patients undergoing arthroscopic rotator cuff repair. The TXA group underwent injection of a 100-mL mixture of 1,000 mg of TXA and normal saline solution intravenously whereas the control group was administered the same volume of normal saline solution at 10 minutes preoperatively.

Are Rotator Muscle Performance and Posterior Shoulder Capsule Tightness Related to Glenohumeral Internal Rotation Deficit in Male College Baseball Players?

Background: Posterior inferior capsule (PIC) tightness in the shoulder joint, a known risk factor for shoulder injury, can be assessed using shear-wave ultrasound elastography (SWE). However, to date, the correlation between PIC elasticity and shoulder rotator muscle performance in college baseball players with glenohumeral internal rotation deficit (GIRD) has not been reported. This study aimed to analyze the differences in PIC elasticity measured using SWE and shoulder rotator muscle performance between male college baseball players with and without GIRD.

Submolecular Ligand Size and Spacing for Cell Adhesion.

Cell adhesion occurs when integrin recognizes and binds to Arg-Gly-Asp (RGD) ligands present in fibronectin. In this work, submolecular ligand size and spacing are tuned via template-mediated in situ growth of nanoparticles for dynamic macrophage modulation. To tune liganded gold nanoparticle (GNP) size and spacing from 3 to 20 nm, in situ localized assemblies of GNP arrays on nanomagnetite templates are engineered.

Manipulating Nanoparticle Aggregates Regulates Receptor-Ligand Binding in Macrophages.

The receptor-ligand interactions in cells are dynamically regulated by modulation of the ligand accessibility. In this study, we utilize size-tunable magnetic nanoparticle aggregates ordered at both nanometer and atomic scales. We flexibly anchor magnetic nanoparticle aggregates of tunable sizes over the cell-adhesive RGD ligand (Arg-Gly-Asp)-active material surface while maintaining the density of dispersed ligands accessible to macrophages at constant.

Dynamic Ligand Screening by Magnetic Nanoassembly Modulates Stem Cell Differentiation.

In native microenvironment, diverse physical barriers exist to dynamically modulate stem cell recruitment and differentiation for tissue repair. In this study, nanoassembly-based magnetic screens of various sizes are utilized, and they are elastically tethered over an RGD ligand (cell-adhesive motif)-presenting material surface to generate various nanogaps between the screens and the RGDs without modulating the RGD density. Large screens exhibiting low RGD distribution stimulate integrin clustering to facilitate focal adhesion, mechanotransduction, and differentiation of stem cells, which are not observed with small screens.

Correlation of glenohumeral internal rotation deficit with shear wave ultrasound elastography findings for the posterior inferior shoulder capsule in college baseball players.

Background: The glenohumeral internal rotation deficit (GIRD), primarily caused by the tightness of the posterior capsule, is a major risk factor for shoulder injuries in overhead throwing athletes. Quantitative evaluation of posterior capsular thickness and tightness can help determine the relationship between the posterior inferior capsule and GIRD. One previous study has assessed posterior capsule tightness using shear wave elastography (SWE), in college baseball players; however, it did not address the cutoff value of capsular elasticity that could be considered as abnormal capsular tightness.

Which muscle performance can be improved after arthroscopic Bankart repair?

Background: There are no published reports available regarding neuromuscular control recovery in nonathletic patients after arthroscopic (A/S) Bankart repair. This study aimed to compare neuromuscular control and performance of the rotator cuff muscles between patients who underwent A/S Bankart repair and normal controls.

Methods: In total, 32 nonathletic patients who underwent A/S Bankart repair were compared with 32 asymptomatic nonathletic volunteers.

The Characteristics of Shoulder Muscles in Archery Athletes.

Background: This study evaluated the shoulder girdle muscle characteristics of elite archery athletes and provides suggestions for archery training programs.

Methods: This study enrolled 15 cases of high level archery athletes (7 males, 8 females) and 30 cases of (15 males, 15 females) sex, age-matched, healthy, non-athletic individuals. We measured peak torques of flexion (FL), extension (EX), abduction (ABD), adduction (ADD), external rotation (ER) and internal rotation (IR) of both shoulders at an angular velocity of 30°/sec, 60°/sec, and 180°/sec.

Can Shoulder Muscle Activity Be Evaluated With Ultrasound Shear Wave Elastography?

Background: Quantitative assessment of rotator cuff muscle activity is important in the treatment of shoulder disorders. However, the known methods for assessing rotator cuff muscle activity thus far have been inaccurate, invasive, and inconvenient.

Questions/purposes: (1) Does the activity of the deltoid, supraspinatus, and infraspinatus muscles measured using ultrasound shear wave elastography have a linear correlation with muscle activity assessed using generally used methods, including isokinetic dynamometry and electromyography? (2) Does the activity of the deltoid, supraspinatus, and infraspinatus muscles measured using shear wave elastography show good intraobserver and interobserver reliability?

Methods: Twelve volunteers participated in intrasession reliability experiments.

Time to peak torque and acceleration time are altered in male patients following traumatic shoulder instability.

Background: Numerous authors have evaluated the strength of the rotator cuff muscles in patients with shoulder instability. However, only limited data are available with regard to neuromuscular control in patients with traumatic anterior shoulder instability, in particular at 90° of abduction. This study was designed to assess muscle strength and neuromuscular control ability using time to peak torque and acceleration time in nonathletic patients with traumatic anterior shoulder instability.

Lower shoulder abduction during throwing motion may cause forceful internal impingement and decreased anterior stability.

Background: Internal impingement and decreased anterior stability, which result from shoulder capsular loosening, are common shoulder pathologies in throwing athletes. The purpose of this study was to assess the effect of shoulder abduction angle on shoulder internal impingement and anterior shoulder stability during the simulated throwing motion.

Methods: Eight cadaveric shoulders were tested by simulating the late-cocking and acceleration phases of the throwing motion for intact and thrower's shoulder conditions.

Ultrasound-guided injection for De Quervain's disease: Accuracy and its influenceable anatomical variances in first extensor compartment of fresh cadaver wrists.

Background: This study was designed to evaluate the accuracy of ultrasound-guided injection targeting EPB tendon sheath and influenceable anatomical variances to the accuracy in the first extensor compartment of fresh cadaver wrists.

Methods: Thirty wrists of 15 cadavers were used. The wrists were divided into right-sided wrists (control group) and left-sided wrists (group A) to compare the accuracy of the manual injection technique (control group) and ultrasound-guided injection technique (group A) targeting EPB tendon sheath.

What Is the Critical Value of Glenoid Bone Loss at Which Soft Tissue Bankart Repair Does Not Restore Glenohumeral Translation, Restricts Range of Motion, and Leads to Abnormal Humeral Head Position?

Background: A general consensus has been formed that glenoid bone loss greater than 20% to 25% is the critical amount at which bony augmentation procedures are needed; however, recent clinical results suggest that the critical levels must be reconsidered to lower values.

Purpose: This study aimed to find the critical value of anterior glenoid bone loss when a soft tissue repair is not adequate to restore anterior-inferior glenohumeral translation, rotational range of motion, or humeral head position using a biomechanical anterior shoulder instability model.

Study Design: Controlled laboratory study.

Remplissage of an Off-track Hill-Sachs Lesion Is Necessary to Restore Biomechanical Glenohumeral Joint Stability in a Bipolar Bone Loss Model.

Purpose: To validate the glenoid track concept in a cadaveric bipolar bone loss model and to test whether "on-track" and "off-track" lesions can be stabilized with Bankart repair (BR) with or without Hill-Sachs remplissage (HSR).

Methods: Eight fresh-frozen cadaveric shoulders were tested in a custom apparatus with passive axial rotation and then progressive translational loading (10 to 40 N) at mid-range (60°) and end-range external rotation (90°). Injury conditions included glenoid bone loss of 15% with on-track (15%) and off-track (30%) Hill-Sachs lesions.

Disparity between Clinical and Ultrasound Examinations in Neonatal Hip Screening.

Background: For early detection of developmental dysplasia of the hip (DDH), neonatal hip screening using clinical examination and/or ultrasound has been recommended. Although there have been many studies on the reliability of both screening techniques, there is still controversy in the screening strategies; clinical vs. selective or universal ultrasound screening.

Virtual Bernese osteotomy using three-dimensional computed tomography in hip dysplasia.

Background: Accurate assessment of acetabular morphology and its relationship to the femoral head is essential for planning a periacetabular osteotomy. We observed the acetabular coverage after virtual Bernese osteotomy using computer-aided technique.

Methods: Three-dimensional computed tomography of 18 normal hips and 3 symptomatic dysplastic hips were analyzed.

Arthroscopic transtibial posterior cruciate ligament reconstruction with preservation of posterior cruciate ligament fibers: clinical results of minimum 2-year follow-up.

Background: The transtibial technique for posterior cruciate ligament reconstructions can potentially lead to poor clinical outcomes due to the "killer turn" effect.

Hypothesis: Preserving the original posterior cruciate ligament fibers in the reconstruction will contribute significantly to the posterior stability of the knee joint, healing of the graft, and prevention of graft failure.

Study Design: Case series; Level of evidence, 4.