Minor Insertion Research Articles

Lower trapezius and latissimus dorsi transfer relieve teres minor activity into the physiological range in Collin D irreparable posterosuperior massive rotator cuff tears: a biomechanical analysis

Tendon transfers are established techniques to regain external rotation mobility in patients suffering from an irreparable, posterosuperior massive rotator cuff tear (MRCT). Posterosuperior MRCT with intact teres minor (Type D MRCT) can lead to excessive teres minor loading to maintain external rotation. We hypothesize that tendon transfers are effective in relieving teres minor loading in Type D MRCTs. Our aim was to biomechanically assess muscle synergism with latissimus dorsi (LD-Transfer) and lower trapezius (LT-Transfer) tendon transfer during external rotation at different abduction heights. Using musculoskeletal modeling, we analyzed and compared the moment arm, muscle torque and muscle activity between a healthy and Type D MRCT pathological model with and without the LD- or LT-Transfer at infraspinatus and teres minor insertion sites. Output measures were analyzed during external rotation at different abduction angles and 10 to 50N resistance against external rotation. We assessed its impact on teres minor loading in a Type D MRCT. Morphological variations were parameterized using the critical shoulder angle and the acromiohumeral distance to address variations among patients. Both transfer types reduced teres minor torque and activity significantly, reaching physiological state at 40N external resistance (p<0.001), with insertion to infraspinatus site being more effective than teres minor site (p<0.001). External rotation moment arms of LD-Transfer were larger than LT-Transfer at 90° abduction (25.1±0.8mm vs. 21.2±0.6mm, p<0.001) and vice versa at 0° abduction (17.4±0.5mm vs. 24.0±0.2mm, p<0.001). While the healthy infraspinatus was the main external rotator in all abduction angles (50-70% torque), a Type D MRCT resulted in a 70-90% increase of teres minor torque and an up to sevenfold increase in its activity leading to excessive loadings beyond 10N resistance against external rotation. Varying the critical shoulder angle and the acromiohumeral distance led to minor variations in muscle moment arm and muscle activity. We identified biomechanical efficacy of both tendon transfers in Type D MRCT regarding teres minor load relieve and superior performance of the transfers at the infraspinatus insertion site.

Anatomical Variations in the Pectoralis Minor Muscle Origin and Insertion: A Systematic Review.

The pathology of the shoulder is among the most widespread medical presentations and may be a result of existing anatomical variations. Therefore, the knowledge of the variations is vital for physicians and clinicians, tasked with treating patients presenting similar complaints to minimize misdiagnosis and prevent iatrogenic injuries. Therefore,the main objective of the present systematic review the variations in pectoralis minor muscle origin and insertion/attachment point. The study also seeks to better inform physicians and clinicians of the task of treating patients with various pathology problems and to ascertain that, upon identification, the pectoralis minor muscle variants are aptly appreciated. The search method used in this systematic review entails the use of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol, and the searching of several online databases, for studies focusing on variations in pectoralis minor muscles. The author reviewer evaluated the studies for eligibility, and the selection criteria for the studies used are described below. This systematic review has disclosed that, in some individuals, the pectoralis minor muscles have their origins in the second, third, and fourth ribs, even as others have their origin in the third and fourth ribs. Still, the systematic review has disclosed that, in certain individuals, the insertion of the pectoralis minor muscle occurs at the supraspinatus tendon, even as there are anomalies in the pectoralis minor insertion points linked to subacromial impingement, possible compression of the brachial plexus anteromedial and the axillary artery, and the subcoracoid impingement.

Poster 180: Diagnostic Algorithm and Outcomes of Treatment for Neurogenic Pectoralis Minor Syndrome

Objectives:Neurogenic pectoralis minor syndrome can generate chronic anterior shoulder pain and a variety of non – specific neurologic symptoms in an affected upper extremity. This study presents a diagnostic algorithm used to identify neurogenic pectoralis minor syndrome and reports short-term outcomes for a series of patients who underwent either open or arthroscopic, coracoid – based, pectoralis minor tenotomy to treat the condition.Methods:Following IRB approval, the senior investigator’s operative records were queried for pectoralis minor release performed between January 2012 and July 2021. Demographic, surgical, and outcomes data was extracted from each subject’s medical record. Only subjects with a minimum of 30-day follow-up were considered in data analysis. Generalized descriptive statistical analysis, along with ANOVAs and post-hoc t-tests were performed to compare outcomes of pectoralis minor release.Results:Twenty-one subjects were identified meeting enrollment criteria. Mean age at time of diagnosis was 44.3years (range 17-70 years). Subjects had undergone prior shoulder surgery in 16/21 (76.2%) of cases and 18 (85.7%) were Worker’s Compensation related injuries. All patients had undergone a minimum of 3 months of a structured physical therapy program preoperatively. All patients underwent a diagnostic, ultrasound – guided pectoralis minor block with temporary resolution of self – reported symptoms. Symptoms prior to treatment included anterior shoulder pain and neurologic symptoms in 20/21 (95.2%) cases, with a mean duration of 15.7 months (range 3-40 months). Pretreatment ASES score was mean 41.5 (range 13.3-73.3) with mean pain of 4.9/10 (range 1-9/10). At mean 6.8 months post-release, patients reported mean 9.5 point increase in ASES score versus index score (p<0.05) and 85.0% (17/20 with pre-operative neurologic symptoms) reported complete resolution or improvement of neurologic symptoms related to neurogenic pectoralis minor syndrome.Conclusions:Findings of insertional pectoralis minor tenderness to palpation with or without reproduction of neurologic symptoms, a positive diagnostic, ultrasound – guided pectoralis minor block and anterior shoulder pain can be useful findings to establish the difficult diagnosis of neurogenic pectoralis minor syndrome. In select patients either open or arthroscopic release of the pectoralis minor insertion on the medial aspect of the coracoid process can alleviate symptoms.

Psoas Minor: Major Confusion

Introduction &amp; ObjectiveThe psoas minor muscle is found in the retroperitoneum with close association to the psoas major and iliacus muscles. Major anatomical textbooks fail to offer a clear consensus on psoas minor, providing conflicting information on the insertion site, function, and relationship to the iliopsoas complex. Reported prevalence of the psoas minor muscle ranges from 40‐65% in each individual hip, but available research is limited by sample size or is not representative of U.S. demographics. Accurate descriptions of the structure of the psoas minor muscle would allow for improved hypotheses regarding muscle function and repercussions of muscle dysfunction. This study aims to document the presence and insertion of the psoas minor muscle in a U.S. donor population, suggest an alternative source to lumbar back pain, and discuss ramifications of muscle dysfunction and applicable osteopathic intervention.Materials &amp; MethodsAt this time, eleven donors were evaluated in the Sam Houston State University College of Osteopathic Medicine’s Human Anatomy Lab. The presence or absence of the psoas minor muscle was determined bilaterally. Muscles were manually traced from origin to the tendon and then the point of insertion. If needed, the inguinal ligament and anterior pelvic structures were dissected for better visualization. Findings were recorded in a secure database and photographed.ResultsThe psoas minor muscle was present bilaterally in seven donors, present unilaterally in one donor, and bilaterally absent in three donors. On all donors evaluated, the insertion site was the pectin pubis with distal blending of the tendon with iliac fascia.Significance &amp; ConclusionAnatomical texts have a variety of descriptions for the documented insertion, such as the pectin pubis, iliopubic eminence, arcuate line, pectineal line or iliopubic ramus. In this study, donors with a psoas minor muscle were determined to have a common insertion site: the pectin pubis. Muscle origin (lateral surface of T12‐L1 vertebral bodies and discs) and bilateral presence (n=7/11; 63%) in the study aligned with current literature.Findings of this study support hypotheses of alternative sources of dysfunction that may contribute to lumbar back pain and hip snapping syndrome rather than more commonly reported sources, such as lumbar back musculature or the iliacus and psoas major muscles. Proximal dysfunction of a psoas minor muscle may contribute to lumbar back pain by abnormally rotating the originating vertebrae in the direction of the hypertrophic muscle. Distal dysfunction may contribute to hip snapping syndrome, in which the iliopsoas tendon “snaps” over the iliopectineal eminence when returning the leg from a position of flexion, abduction, or external rotation. From an osteopathic manipulative approach, the psoas minor may be treated with counterstrain techniques or muscle energy to the lumbar spine to restore normal tone and function. We will continue to collect data in an ongoing study in order to provide an evidence‐based recommendation for the reporting of psoas minor insertion and function, as well as the presentation and potential treatment of psoas minor dysfunction.

TROCHANTERIC ATTACHMENT OF PSOAS MINOR MUSCLE IN 52 YEARS OLD FEMALE CADAVER IN ALKHARJ, SAUDI ARABIA

The anatomical variations of psoas minor muscle (PMM) vary greatly in terms of agenesis, attachments and morphology based on race and gender. In the current study, we report an extremely rare condition of distal attachment of psoas minor muscle during our routine dissection of a 52-year-old female body cadaver. We observed that the psoas minor muscle insertion was unique where it was inserted to the lesser trochanter of the femur. We believe that understanding these variations is essential to the effective execution and planning of radiological and surgical procedures and the correlation with many clinical conditions.

INVESTIGATING BLOOD SUPPLY TO THE CORACOID BONE GRAFT IN LATARJET PROCEDURES — A CADAVERIC STUDY

Background: The Classic Latarjet Procedure (CLP) is a proven method for increasing anterior shoulder stability, where the posterior aspect of an osteotomized coracoid is fixed to the glenoid rim. De Beer’s Congruent-Arc Technique (CAT) is a recognized variation where the medial aspect of the coracoid is fixed to the glenoid. Consolidation of the coracoid graft depends on the compression achieved and the vascularity of the graft. Nonunion rates of 9.4% have been documented in the literature. Methods: Ethical approval was granted for our study by the medical school ethics board. Eight cadaveric shoulders were dissected using the standard deltopectoral approach. In each limb, the blood supply to the coracoid was identified, photographed, and protected. The coracoid process was osteotomized at its elbow and a bone transfer was performed. The effects on the coracoid blood supply of CLP vs CAT were noted. Results: In all cases, the blood supply to the coracoid process arose directly from the axillary artery, bifurcating close to the tip of the coracoid. CLP was performed with no disruption to the arterial supply of the coracoid or pectoralis minor. CAT was found to stretch the arterial supply in most specimens, potentially impacting blood supply to the coracoid. CAT also requires the sacrifice of the arterial branch to the insertion of the pectoralis minor. Conclusion: CLP appears less likely to stretch its arterial supply compared to CAT and allows retention of the arterial branch to pectoralis minor insertion. This has potential implications for graft union and recurrent shoulder instability.

COVID-19 vaccine coverage and the necessity of its urgent development towards Omicron the new SARS CoV-2 B.1.1. 529 variant

A SARS-CoV-2 variant belonging to Pango lineage B.1.1.529 with a significant number of S-gene mutations compared to the original virus was found in early November 2021. On 26th November 2021, the World Health Organization (WHO) designated the mutation as a variant of concern and assigned it the name Omicron. The difference is identified by 30 changes in the spike protein, three minor deletions, and one minor insertion, 15 of which are in the receptor-binding area. The Omicron variant is the most diverging variety discovered in substantial numbers so far during the pandemic, raising significant concerns that it may be associated with significant reductions in vaccination efficacy and an increased risk of reinfections. Omicron pseudo- or live virus isolates are urgently needed to understand better the virus's escape potential against both vaccination, and infection-acquired immunity is urgently required.

Myocardial Perfusion Defects in Hypertrophic Cardiomyopathy Mutation Carriers.

BackgroundImpaired myocardial blood flow (MBF) in the absence of epicardial coronary disease is a feature of hypertrophic cardiomyopathy (HCM). Although most evident in hypertrophied or scarred segments, reduced MBF can occur in apparently normal segments. We hypothesized that impaired MBF and myocardial perfusion reserve, quantified using perfusion mapping cardiac magnetic resonance, might occur in the absence of overt left ventricular hypertrophy (LVH) and late gadolinium enhancement, in mutation carriers without LVH criteria for HCM (genotype‐positive, left ventricular hypertrophy‐negative).Methods and ResultsA single center, case‐control study investigated MBF and myocardial perfusion reserve (the ratio of MBF at stress:rest), along with other pre‐phenotypic features of HCM. Individuals with genotype‐positive, left ventricular hypertrophy‐negative (n=50) with likely pathogenic/pathogenic variants and no evidence of LVH, and matched controls (n=28) underwent cardiac magnetic resonance. Cardiac magnetic resonance identified LVH‐fulfilling criteria for HCM in 5 patients who were excluded. Individuals with genotype‐positive, left ventricular hypertrophy‐negative had longer indexed anterior mitral valve leaflet length (12.52±2.1 versus 11.55±1.6 mm/m2, P=0.03), lower left ventricular end‐systolic volume (21.0±6.9 versus 26.7±6.2 mm/m2, P≤0.005) and higher left ventricular ejection fraction (71.9±5.5 versus 65.8±4.4%, P≤0.005). Maximum wall thickness was not significantly different (9.03±1.95 versus 8.37±1.2 mm, P=0.075), and no subject had significant late gadolinium enhancement (minor right ventricle‒insertion point late gadolinium enhancement only). Perfusion mapping demonstrated visual perfusion defects in 9 (20%) carriers versus 0 controls (P=0.011). These were almost all septal or near right ventricle insertion points. Globally, myocardial perfusion reserve was lower in carriers (2.77±0.83 versus 3.24±0.63, P=0.009), with a subendocardial:subepicardial myocardial perfusion reserve gradient (2.55±0.75 versus 3.2±0.65, P=<0.005; 3.01±0.96 versus 3.47±0.75, P=0.026) but equivalent MBF (2.75±0.82 versus 2.65±0.69 mL/g per min, P=0.826).ConclusionsRegional and global impaired myocardial perfusion can occur in HCM mutation carriers, in the absence of significant hypertrophy or scarring.

What Are Practical Surgical Anatomic Landmarks and Distances from Relevant Neurologic Landmarks in Cadavers for the Posterior Approach in Shoulder Arthroplasty?

Traditional total shoulder arthroplasty is performed through the deltopectoral approach and includes subscapularis release and repair. Subscapularis nonhealing or dysfunction may leave patients with persistent pain, impairment, and instability. Alternative approaches that spare the subscapularis include rotator interval and posterior shoulder approaches; however, to our knowledge, a cadaveric study describing pertinent surgical anatomy for a posterior shoulder approach regarding shoulder arthroplasty has not been performed. (1) What are the distances from important neurologic structures of the shoulder for arthroplasty through a posterior approach? (2) What surgical landmarks can help identify the internervous interval between the infraspinatus and teres minor? Twelve hemitorso cadaver specimens with intact rotator cuffs were dissected to study posterior shoulder anatomy regarding posterior shoulder arthroplasty. The median (range) age of the specimens was 79 years (55 to 92). Six of the 12 specimens were right-hand dominant, and 10 specimens were male. Cadaver height was a median 171 cm (155 to 191) and weight was a median of 68 kg (59 to 125). A posterior deltoid split and internervous approach between the infraspinatus and teres minor were used. A posterior T capsulotomy was performed. The distances to important neurologic structures were measured with an electronic caliper and provided in median (range) distances in millimeters. Although not as meaningful as distance ratios accounting for a specimen's body size, neurologic distances in millimeters are surgically practical and provide intraoperative usefulness. Surgical landmarks that can help identify the infraspinatus and teres minor plane were noted. Practical visual and tactile cues between the infraspinatus and teres minor were identified. Posterior rotator cuff tendon morphologies and widths were recorded. The closest important neurologic structure was the axillary nerve, measuring a median (range) 17 mm (9 to 19) from the inferior glenoid rim while the infraspinatus branch of the suprascapular nerve measured 21 mm (15 to 36) from the posterior glenoid rim. The axillary nerve measured 84 mm (70 to 97) from the posterior tip of the acromion in the deltoid split. Three surgical landmarks were helpful for identifying the plane between the infraspinatus and teres minor in all 12 specimens: (1) identifying the triangular teres minor tendon insertion, (2) medial palpation identifying the low point between the prominent muscle bellies of the infraspinatus and teres minor, and (3) identifying the distinct and prominent teres minor tubercle, which is well localized and palpable. A major benefit of the posterior approach for shoulder arthroplasty is subscapularis preservation. Multiple practical surgical cues are consistently present and can help identify the infraspinatus and teres minor interval. We did not find the presence of fat stripes to be helpful. The suprascapular nerve is in proximity to posterior surgical dissection and differs from the deltopectoral approach. This is an important distinction from an anterior approach and requires care with dissection. Future studies are necessary to assess iatrogenic risk to the posterior rotator cuff and external rotation strength. This may entail intraoperative nerve conduction studies of the posterior rotator cuff and clinical studies assessing external rotation strength. Studying posterior shoulder anatomy is an initial first step to assessing the feasibility of the posterior approach for anatomic shoulder arthroplasty. Additional studies assessing the degree of glenohumeral exposure and possible iatrogenic posterior rotator cuff injury are necessary. Because of the proximity of neurologic structures, it is recommended that surgeons not perform this technique until sufficient evidence indicates that it is equivalent or superior to standard anterior approach total shoulder arthroplasty. After such evidence is available, proper training will be necessary to ensure safe use of the posterior shoulder approach.

Removal of impalpable contraceptive implants

A paired-rod, subdermal, implant system (JadelleR) is one of the popular methods of long term reversible contraceptive methods in Sri Lanka. The longer duration of action, low failure rate and comfort of the implant greatly outweigh the inconvenience of a minor surgical insertion and removal procedure. Even though the insertion is usually simple, minor, quick and safe, the removal sometimes is difficult and may require surgical intervention under anaesthesia. This article describes the background information on impalpable implants and the technique of their removal.

Hg19KIndel: ethnicity normalized human reference genome

BackgroundThe most widely used human genome reference assembly hg19 harbors minor alleles at 2.18 million positions as revealed by 1000 Genome Phase 3 dataset. Although this is less than 2% of the 89 million variants reported, it has been shown that the minor alleles can result in 30% false positives in individual genomes, thus misleading and burdening downstream interpretation. More alarming is the fact that, significant percentage of variants that are homozygous recessive for these minor alleles, with potential disease implications, are masked from reporting.ResultsWe have demonstrated that the false positives (FP) and false negatives (FN) can be corrected for by simply replacing nucleotides at the minor allele positions in hg19 with corresponding major allele. Here, we have effectively replaced 2.18 million minor alleles Single Nucleotide Polymorphism (SNPs), Insertion and Deletions (INDELs), Multiple Nucleotide Polymorphism (MNPs) in hg19 with the corresponding major alleles to create an ethnically normalized reference genome called hg19KIndel. In doing so, hg19KIndel has both corrected for sequencing errors acknowledged to be present in hg19 and has improved read alignment near the minor alleles in hg19.ConclusionWe have created and made available a new version human reference genome called hg19KIndel. It has been shown that variant calling using hg19KIndel, significantly reduces false positives calls, which in-turn reduces the burden from downstream analysis and validation. It also improved false negative variants call, which means that the variants which were getting missed due to the presence of minor alleles in hg19, will now be called using hg19KIndel. Using hg19KIndel, one even gets a better mapping percentage when compared to currently available human reference genome. hg19KIndel reference genome and its auxiliary datasets are available at https://doi.org/10.5281/zenodo.2638113

Biomechanics of lower trapezius and latissimus dorsi transfers in rotator cuff–deficient shoulders

Irreparable posterosuperior rotator cuff tears cause pain and impaired shoulder function. Latissimus dorsi (LD) transfer has been proven to improve shoulder function, but lower trapezius (LT) transfer has recently been proposed as an alternative. This study aimed to compare the biomechanics of LD and LT transfers and how they are affected by different insertion sites. The Newcastle shoulder model was used to investigate the biomechanics of these 2 tendon transfers. Computed tomography data sets from 10 healthy subjects were used to customize the model, and virtual LD and LT transfers were performed on supraspinatus, infraspinatus, and teres minor insertion sites. Muscle moment arms and lengths were computed for abduction, forward flexion, and external rotation. The LT yields greater abduction moment arms compared with the LD when it is transferred to the native supraspinatus and infraspinatus insertion sites. However, they become adductors when transferred to the native teres minor insertion. Both muscles show strong external rotation moment arms, except for the LT with a supraspinatus insertion. Resting muscle strains were 0.21 (±0.03), 0.12 (±0.02), and 0.06 (±0.03) for the LD and 0.70 (±0.15), 0.61 (±0.13), and 0.58 (±0.13) for the LT for the supraspinatus, infraspinatus, and teres minor insertions, respectively. LT provided better abduction and external rotation moment arms when transferred to the infraspinatus insertion. LD performed better when transferred to the supraspinatus insertion. Overall, LT transfer showed a biomechanical advantage compared with LD transferbecause of stronger abduction moment arms. However, significantly larger muscle strains after LT transfer necessitatea tendon allograft to prevent muscle overtensioning.

Canonical DNA minor groove insertion of bisbenzamidine-Ru(ii) complexes with chiral selectivity.

We report the first Ru(ii) coordination compounds that interact with DNA through a canonical minor groove insertion mode and with selectivity for A/T rich sites. This was made possible by integrating a bis-benzamidine minor groove DNA-binding agent with a ruthenium(ii) complex. Importantly, one of the enantiomers (Δ-[Ru(bpy)2 b4bpy]2+, Δ-4Ru) shows a considerably higher DNA affinity than the parent organic ligand and the other enantiomer, particularly for the AATT sequence, while the other enantiomer preferentially targets long AAATTT sites with overall lower affinity. Finally, we demonstrate that the photophysical properties of these new binders can be exploited for DNA cleavage using visible light.

Anatomic analysis of the whole articular capsule of the shoulder joint, with reference to the capsular attachment and thickness

BackgroundAlthough conventional Bankart repair has been the accepted procedure for traumatic anterior glenohumeral instability, the humeral avulsion of the glenohumeral ligament or an elongation of the capsule remains challenging to decide the appropriate treatment. The anatomical knowledge regarding the whole capsule of glenohumeral joint is necessary to accurately treat for the capsular disorders. The aims of the current study were to investigate the anatomical features of capsular attachment and thickness in a whole capsule of glenohumeral joint.MethodsWe used 13 shoulders in the current study. In 9 shoulders, we macroscopically measured the attachment widths of the capsulolabrum complex on the scapular glenoid, and the attachment widths of the capsule on the humerus in reference to the scapular origin of the long head of triceps brachii, and the humeral insertion of the rotator cuff tendons. We additionally used 4 cadaveric shoulders, which were embalmed using Thiel’s method, for the analysis of the thickness in a whole capsule by using micro-CT.ResultsThe glenoidal attachment of the articular capsule appeared to have a consistent width except for the superior part of the origin of the long head of triceps brachii. On the humerus, the articular capsule was widely attached to areas without overlying rotator cuffs, with the widest width (17.3 ± 0.9 mm) attached to the axillary pouch. The inferior part of the capsule, which was consistently thicker than the superior part, continued to the superior part along the glenoid and humeral side edge.ConclusionsThe current study showed that the inferior part of the glenohumeral capsule had a wide humeral attachment from the inferior edge of the subscapularis insertion to the inferior edge of the teres minor insertion via the anatomical neck of the humerus, and the thickness of it was thicker than the superior part of the capsule.

The imaging features of the meniscal roots on isotropic 3D MRI in young asymptomatic volunteers.

Background:This study aimed to describe clearly the normal imaging features of the meniscal roots on the magnetic resonance imaging (MRI) with a 3-dimensional (3D) proton density-weighted (PDW) sequence at 3T.Methods:A total of 60 knees of 31 young asymptomatic volunteers were examined using a 3D MRI. The insertion patterns, constitution patterns, and MR signals of the meniscal roots were recorded.Results:The anterior root of the medial meniscus (ARMM), the anterior root of the lateral meniscus (ARLM), and the posterior root of the medial meniscus (PRMM) had 1 insertion site, whereas the posterior root of the lateral meniscus (PRLM) can be divided into major and minor insertion sites. The ARLM and the PRMM usually consisted of multiple fiber bundles (≥3), whereas the ARMM and the PRLM often consisted of a single fiber bundle. The ARMM and the PRLM usually appeared as hypointense, whereas the ARLM and the PRMM typically exhibited mixed signals.Conclusions:The meniscal roots can be complex and diverse, and certain characteristics of them were observed on 3D MRI. Understanding the normal imaging features of the meniscal roots is extremely beneficial for further diagnosis of root tears.

Novel Surgical Approach for Decompression of the Scalene Triangle in Neurogenic Thoracic Outlet Syndrome.

Thoracic outlet syndrome (TOS) is a cause of upper extremity and shoulder dysfunction. TOS can present with a wide range of symptoms due to compression of the brachial plexus or its branches during their passage through the cervicothoracobrachial region or scalene triangle. There are three types of TOS: arterial, venous, and neurogenic. Neurogenic TOS (nTOS) is by far the most frequent type and represents more than 95% of all cases. Historically, surgical intervention for all types of TOS has evolved based on the treatment for a vascular etiology and has typically included a first rib resection. Despite nTOS being by far the more common type, most previous interventions have not considered treatment via peripheral nerve decompression.We describe surgical treatment of nTOS, performed on an outpatient basis, which focuses on the surgical decompression of the structures associated with the scalene triangle in conjunction with release of the pectoralis minor insertion through limited incisions. The procedure avoids the morbidity associated with first rib resection and is successful in ameliorating nTOS symptoms. Further, we propose a nomenclature shift to scalene triangle syndrome (STS) to reflect the nerve and arterial compressions needing to be addressed.

Anatomic measurements of the coracoid and its implication in the Latarjet procedure

Background: Latarjet procedure is frequently done to treat shoulder instability. It includes osteotomizing the coracoid distal to the insertion of coracoclavicular ligament. Knowledge of the insertion of the trapezoid ligament is important to determine the level of coracoid osteotomy. Methods: Ten shoulders were dissected free of overlying soft tissue while preserving the ligament and muscle attachment on the coracoid. The distance between the tip of the coracoid to the coracoclavicular ligament and the pectoralis minor insertion width on the coracoid was measured. Result: The average distance from the tip of the coracoid to the trapezoid insertion was 2.6 cm. The average pectoralis minor insertion width was 1.9 cm. Conclusion: To preserve the insertion of the trapezoid ligament, the coracoid should be osteotomized less than 2.6 cm from the tip of the coracoid.

Pectoralis minor tendon in the rotator interval: arthroscopic, magnetic resonance imaging findings, and clinical significance

Although insertional variation of the pectoralis minor on the rotator interval has been reported, more detailed characteristics as seen on magnetic resonance imaging (MRI) or arthroscopy and clinical significance have been rarely discussed. This study evaluated the prevalence of tendinous insertion of the pectoralis minor by arthroscopy and diagnostic performances of MRI and suggests its clinical implication in rotator cuff repair. The study prospectively recruited 99 consecutive patients for arthroscopic exploration of pectoralis minor insertion. Preoperative MRIs were evaluated to detect tendinous insertion of the pectoralis minor by 2 independent, blinded observers, and these results were correlated with arthroscopy as the gold standard. During arthroscopy, the effect of this variation on supraspinatus tendon tear and repair was evaluated. Tendinous insertion of the pectoralis minor was found in 11 patients (11%) at arthroscopy. The sensitivity and specificity of MRI were 64% (95% confidence interval [CI], 31%-89%), the specificity was 82% (95% CI, 72%-89%), and the accuracy was 80% (95% CI, 72%-88%). Intraobserver and interobserver reliability tests showed moderate agreements. In 7 patients, it tethered the retracted supraspinatus tendon from mobilization and gave rise to tension on the repaired cuff, which warranted complete resection of the pectoralis minor tendon for a tension-free cuff repair. Tendinous insertion of the pectoralis minor existed with 11% prevalence in our series and could be preoperatively detected on MRI. During arthroscopic rotator cuff repair, it can be an obstacle to supraspinatus tendon mobilization and repair.

Natural Nanotubes Reinforcing Heterophasic Polypropylene

Nanocomposites of high-impact polypropylene resin and organosilane-functionalized nanotubes in halloysite clay were prepared with the introduction of peroxide to promote selective incorporation of the filler into the polypropylene phase of the matrix, with minor insertion into the EPR elastomeric phase, thus improving the stiffness while preserving the high toughness of the material. Silica composites were also prepared as standard filler. The effect of increasing load content on the morphological and mechanical properties of this material was evaluated by SEM and DMA. The content of the hexane-extracted fraction of these composites after processing was evaluated. Halloysite was well-dispersed in the matrix. Composites with 10% of filler and 0.5% w/w of dicumyl peroxide had increased stiffness and higher loss factor. An increase of the E’ was generated by halloysite addition, but there was a higher decrease in Tan delta. Studies using experimental planning as a tool enabled choosing appropriate amounts of DCP to obtain a high performance composite.

Mixing ALD/MLD-grown ZnO and Zn-4-aminophenol layers into various thin-film structures

Building 2D inorganic-organic hybrids by combining inorganic and organic constituents with molecular-layer precision is an attractive approach to fabricate novel materials with a tailored combination of properties from both entities. Here we demonstrate the potential of the combined atomic and molecular layer deposition (ALD/MLD) technique for the state-of-the-art synthesis of such materials and to fabricate both homogeneous thin-film mixtures and nanolaminates of ZnO and the Zn-4-aminophenol inorganic-organic hybrid. The thin films are deposited by varying the number of precursor cycles during the depositions. Diethyl zinc and 4-aminophenol (AP) are used as precursors for the Zn-AP hybrid depositions, and diethyl zinc and water for the ZnO depositions. The characterization of the mixed Zn-AP and ZnO films reveals that crystallinity, density, surface roughness, chemical stability, hardness and contact modulus are sensitively altered by even a minor insertion of Zn-AP hybrid into the ZnO structure. Fabrication of Zn-AP + ZnO nanolaminates with different thicknesses of the Zn-AP and ZnO layers provides us with an even better way to control the hardness and contact modulus, and also to enhance the chemical stability of the films.