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BackgroundHumeral avulsion of the glenohumeral ligaments (HAGL) has become a recognized cause of recurrent shoulder instability; however, it is unknown whether small and large HAGL lesions have similarly destabilizing effects and if large lesion repair results in restoration of stability.Questions/purposesIn a cadaver model, we evaluated the effect of small and large HAGL lesions and large HAGL lesion repair on glenohumeral ROM, translation, and kinematics.MethodsWe measured rotational ROM, humeral head translation under load, and humeral head apex position in eight cadaveric shoulders. Each specimen was tested in 60° glenohumeral abduction in the scapular and coronal planes under four conditions: intact, small HAGL lesion (mean ± SD length, 18 ± 1.8 mm), large HAGL lesion (36.8 ± 3.6 mm), and after large HAGL lesion repair. For each condition, we measured maximum internal and external rotation with 1.5 Nm of torque; glenohumeral translation in 90° external rotation with 15- and 20-N force applied in the anterior, posterior, superior, and inferior directions; and humeral head apex position throughout ROM. Repeated-measures ANOVA was used for statistical analysis.ResultsSmall HAGL lesions did not change ROM, translation, or kinematics from the normal shoulder; however, these parameters changed with large HAGL lesions. Maximum external rotation and total ROM increased in the scapular (13.8° ± 9.4°, p < 0.001; 19.0° ± 16.5°, p < 0.001) and coronal (21.4° ± 10.6°, p < 0.001; 29.1° ± 22.1°, p < 0.001) planes. With anterior force, anterior-inferior translation increased in both planes (mean increase for both loads and planes: anterior: 9.1 ± 9.5 mm, p < 0.01; inferior, 5.7 ± 6.6 mm, p < 0.03). In the coronal plane, posterior and inferior translation also increased (4.9 ± 5.4 mm, p < 0.01; 7.1 ± 9.9 mm, p < 0.03; averaged for both loads). The humeral head apex shifted 3.7 ± 4.9 mm anterior (p = 0.04) and 2.8 ± 2.6 mm lateral (p = 0.004) in the scapular plane and 3.7 ± 3.4 mm superior (p = 0.006) and 4.1 ± 2.6 mm lateral (p < 0.001) in the coronal plane. HAGL lesion repair decreased ROM and translation in both planes and restored humeral head position in maximum external rotation.ConclusionsAnterior large HAGL lesions increase ROM and glenohumeral translation. After large HAGL lesion repair, stability of the shoulder can be restored.Clinical relevanceSurgeons should be aware of the possibility of HAGL lesions in patients with shoulder instability, and if large HAGL lesions are diagnosed, surgeons should consider repairing the lesions.

The performance of electrothermal-chemical (ETC) guns, besides being dependent on the total energy used, is also influenced by the time frame over which electric energy is deposited. This means the current pulse shaping is an important factor in increasing the pressure pulsewidth within the limit of the gun design pressure. For experiment design, it is necessary to predict the load resistance to supply the required shape of current pulses into the gun load. But it is difficult to identify the load resistance theoretically because the dynamic interactions of plasma with propellants should be understood. In this paper, it is suggested that the measured current and voltage can be utilized to develop an approximated model of the load resistance. It is also shown that the load resistance depends on the discharging voltage and current. Experimental tests have been performed with several shapes of current pulses to validate the resistance model. Index Terms--Electrothermal-chemical (ETC), load resistance, time-varying system parameter.

Background Accurate nomenclature of variants is an essential element for genetic diagnosis and patient care. Objective To investigate annotation differences of clinical variants between annotation tools. Methods We analyzed 218,156 clinical variants from the Human Gene Mutation Database. Multiple nomenclatures based on RefSeq transcripts were provided using ANNOVAR and snpEff. Results The concordance rate between ANNOVAR and snpEff was approximately 85%. Based on the Human Genome Variation Society (HGVS) nomenclature, snpEff was more accurate than ANNOVAR (coding variants, 99.3% vs 84.9%; protein variants, 94.3% vs 79.8%). When annotating each variant with ANNOVAR and snpEff, the accuracy of nomenclature was 99.5%. Conclusions There were substantial differences between ANNOVAR and snpEff annotations. The findings of this study suggest that simultaneous use of multiple annotation tools could decrease nomenclature errors and contribute to providing standardized clinical reporting. [ABSTRACT FROM AUTHOR]