Variables affecting complication rates in type III paediatric supracondylar humerus fractures

Purpose Unstable supracondylar humerus (SCH) fractures may have different outcomes as a result of direction of displacement and pin configuration. This study evaluates the impact of fracture displacement, pin configuration and fellowship training on clinical and radiographic outcomes in unstable fractures. Methods A total of 99 patients with completely displaced type III fractures were identified at an academic centre and a local community hospital. Patient characteristics and the fellowship training of the treating surgeon were recorded, and injury films documented the direction of displacement. Pin configuration, coronal and sagittal alignment were recorded from postoperative radiographs and at healing. Radiographic outcomes including coronal, sagittal and rotational malunion as well as clinical complications were analyzed. Results Fractures with direct posterior displacement had a lower composite malunion rate compared with those with posterolateral (PL) or posteromedial (PM) displacement (6.9%, 36.4%, 29.2% respectively; p = 0.019). PM displacement had a higher rate of coronal malunion compared with PL (18.2% versus 0%; post hoc p = 0.024). All-lateral constructs resulted in more rotational malunions (20.9% versus 1.8%; p = 0.002) compared with crossed pinning. PL fractures treated with all-lateral fixation showed a trend toward increased rotational instability or malunion (23.8% versus 1.3%; p = 0.073). Higher composite complication rates were noted in patients treated by surgeons with non-paediatric, non-trauma fellowship training. Conclusion For displaced SCH fractures, all-lateral fixation is associated with higher rates of rotational instability and malunion. Posteromedially and posterolaterally displaced fractures have higher rates of malunion compared with fractures with straight posterior displacement. Fellowship training other than paediatric or trauma was associated with increased complications. Level of Evidence Level III

Evaluation of vestibular function in children with purulent media otitis by computer stabilometry

The aim of the research – assessment of vestibular function in children with acute purulent otitis media by computer static stabilometry compared with typically developed children of the same age. Materials and methods: 22 children with purulent otitis media aged 4 to 7 years and 30 practically healthy peers were examined by static stabilometry on the device “MPFI stabilograph 1” (Kharkiv, Ukraine). Indicators of variation and shape of the pressure center distribution, spectral-correlation indicators of stabilograms, as well as integral indicators of stability (length, velocity and angle of postural oscillations) were taken into account and the equilibrium functions of the two sensory states (open and closed eyes) are calculated in the StabiliS software. Results: purulent otitis media causes posterior displacement of the absolute coordinates of the pressure center. In the state with closed eyes, children with purulent otitis differ from their healthy coevals by 14 of 24 stabilometric parameters, including stabilogram length, speed, angle and amplitude of oscillations, giving way to them in the stability of equilibrium. Children with purulent otitis media are more sensitive to the visual canal of postural control than their coevals. Involvement of visual afferents in postural control significantly improves balance maintenance in children with purulent otitis by reducing deviations of postural oscillations, which is reflected in the probable changes of 9 out of 24 stabilometric parameters compared to control. Conclusions: In preschool age, purulent otitis media leads to latent vestibular dysfunction, which is manifested by a violation of the stability of the vertical posture in a state with closed eyes and is compensated by visual-vestibulo-proprioceptive integration in the process of postural control.

Two rare species of Danielsseniinae (Copepoda: Harpacticoida: Pseudotachidiidae) from the Kara and East Siberian Seas, with description of their previously unknown sexes

The previously unknown females of Danielssenia spitsbergensis Gee & Huys, 1994 and males of Mucrosenia kendalli Gee & Huys, 1994 (Pseudotachidiidae, Danielsseniinae) are described based on specimens collected in the Kara and East Siberian Seas. Females of D. spitsbergensis exhibit the main diagnostic features of the genus Danielssenia Boeck, 1873 (antennule four-segmented; proximal segment of antennary exopod with one seta; structure of all the mouthparts; absence of an inner seta on exopod-1 of P2–P4; P5 not fused medially and with distinct exopod and baseoendopod, the latter with five setae; genital field with small copulatory pore and short copulatory duct leading to seminal receptacle with paired anterior chambers). At the same time, these specimens also exhibit some distinctive features which are unique for the species but disagree with the generic diagnosis. These peculiarities validate the placing of D. spitsbergensis as species incertae sedis within Danielssenia and point out the necessity of examination of other ‘Danielssenia-like’ forms before the true taxonomic position of this species can be elucidated. Both males and females of M. kendalli exhibit the autapomorphies of the genus, viz. P2 endopod-2 with a mucroniform process reaching almost to end of endopod-3 (this sexually dimorphic character is more pronounced in the males but also present in females); P2 endopod-2 without inner seta; posterior displacement of caudal ramus seta II; presence of tuft of long setules at inner distal corner of caudal ramus; P2 endopod shorter than exopod; P2–P4 exopod-1 without inner seta. Furthermore, some particular features (anal somite and pseudoperculum morphology; female P1 endopod distinctly longer than exopod; P5 exopod with distinct suture on dorsal surface separating it from the baseoendopod; prominent mucroniform process on P2 endopod-2) of the Kara and East Siberian Sea specimens conform fully with the original description of M. kendalli but apparently differ from M. kliei (Smirnov, 1946), the single female of which was collected from the same region and depth. Therefore, the validity and definite status of the specimen described by Smirnov is still a matter of conjecture pending additional findings and, particularly, the discovery of the male.

Comparison of Accuracy for HKA by X-ray and Knee Motion Analysis System and the Relationships between HKA and Gait Posture

This study is aimed at obtaining the accuracy of the lower limb mechanical axis (Hip-Knee-Ankle, HKA) by the six degrees of freedom (6DOF) of the knee and ground gait data and analyzing the correlation between the lower limb mechanical axis and 6DOF. We analyzed 3D knee kinematics during ground gait of 99 patients with KOA and 80 patients 6 months after the operations with the vivo infrared navigation 3D portable knee joint movement analysis system (Opti-Knee®, Innomotion Inc, Shanghai, China). Significant correlations with low coefficients (r = -0.19, p = 0.01) between HKA value and anterior-posterior displacement for the whole cohort were found. There were significant correlations with moderate to high coefficients (r = 0.784 to 0.976) between the comparisons of HKA measured on the full-length alignment radiographs and 3D knee joint movement analysis system (Opti-Knee). The further linear correlation analysis showed that there was a significant correlation between the values of HKA measured by X-ray and movement analysis system(R2 = 0.90, p < 0.01). Data with equivalent results as HKA could be provided by knee joint movement analysis system comparing with the conventional X-rays. Nonetheless, there was low significance between the HKA and ground gait data .

STUDY ON THE RHINOPHARYNX NEOPLASMS

In order to receive the food bolus, the muscular-fibrous walls of the pharynx contract by reflex, first widening the pharynx, and the palatine veil rises, closing the passage to the rhinopharynx. Then the base of the tongue rises, the piers approach, closing the bucco-pharyngeal passage in the isthmus. The airway is simultaneously interrupted by the posterior displacement of the base of the tongue, the folding of the mucosa of the posterior pharynx, and the lifting and closing of the larynx. The food bolus is thus forced to follow the hypopharyngeal-esophageal pathway, the only one that remains open. In case of paralysis of the nerves that coordinate the swallowing process, the laryngeal sphincter remains open, favoring the false pathway and aspiration bronchopneumonias. The paralysis of the palatine veil prevents its horizontalization during swallowing, which favors the discharge of fluids into the nose, which is significant when the paralysis is bilateral and more discrete when it is unilateral. The clinical prospective and retrospective study material was represented by a number of 190 individuals aged 0 to 80 years, who were hospitalized between 01.01.2011 and 31.12.2019 in the ENT Department of the Teaching Hospital in Galați for follow-up of malignant rhinopharyngeal tumors. Most of these patients subsequently underwent sequential examination to determine their treatment response. Due to its deep location and limited clinical accessibility, onset symptoms are often absent or inconclusive for both the physician and the patient. CT scan is superior to clinical examination in primary tumor evaluation, especially in advanced T3 and T4 cases, which are largely clinically under-rated. Performing the coronal rhinopharynx sections and double-window recording greatly increase the accuracy of examination and they should be considered at least for the initial assessment procedure.

Posterior Displacement of L1 May be a Risk Factor for Proximal Junctional Kyphosis After Adult Spinal Deformity Correction

Study Design: Retrospective cohort study. Objective: Overcorrection in adult spinal deformity (ASD) surgery may lead to proximal junctional kyphosis (PJK) because of posterior spinal displacement. The aim of this paper is to determine if the L1 position relative to the gravity line (GL) is associated with PJK. Methods: ASD patients fused from the lower thoracic spine to sacrum by 4 spine surgeons at our hospital were retrospectively studied. Lumbar-only and upper thoracic spine fusions were excluded. Spinopelvic parameters, the L1 plumb line (L1PL), L1 distance to the GL (L1-GL), and Roussouly type were measured. Results: One hundred fourteen patients met inclusion criteria (63 patients with PJK, 51 without). Mean age and follow up was 65.51 and 3.39 years, respectively. There was no difference between the PJK and the non-PJK groups in baseline demographics, pre-operative and immediate post-operative pelvic incidence-lumbar lordosis mismatch, sagittal vertical axis, or coronal Cobb. The immediate postoperative L1-GL was -7.24 cm in PJK and -3.45 cm in non-PJK ( P < 0.001), L1PL was 1.71 cm in PJK and 3.07 cm in non-PJK ( P = 0.004), and PT (23.76° vs 18.90°, P = 0.026) and TK (40.56° vs 31.39°, P < 0.001) were larger in PJK than in non-PJK. After univariate and multivariate analyses, immediate postoperative TK and immediate postoperative L1-GL were independent risk factors for PJK without collinearity. Conclusions: A dorsally displaced L1 relative to the GL was associated with an increased risk of PJK after ASD surgery. The postoperative L1-GL distance may be a factor to consider during ASD surgery.

Contribution of the peroneus longus neuromuscular compartments to eversion and plantarflexion of the ankle

Compartmentalization of animal and human skeletal muscle by multiple motor nerve branches known as the neuromuscular compartment (NMC) has been observed primarily in muscles that participate in a plane of motion. In this context, the peroneus longus muscle contributes to eversion and plantarflexion of the ankle and the presence of NMCs has been reported. However, no research has reported the selective activation of the compartments of the peroneus longus during the performance of different ankle movements. The purpose of this research was to determine the contribution of peroneus longus NMCs, through multi-channel surface electromyography (sEMG), to eversion and plantarflexion movements. Multi-channel sEMG was recorded from the peroneus longus muscle by using an electrode grid during eversion and plantarflexion of the ankle at 10%, 30%, 50%, and 70% of maximal voluntary isometric contraction (MVIC). The root mean square and displacement of the center of mass position in the X (COMx) and Y (COMy) components were calculated. The primary finding was that eversion showed significantly higher sEMG amplitude than plantarflexion in the posterior compartment in low, moderate, and high percentages of MVIC. However, no significant difference in sEMG amplitude was observed in the anterior compartment between eversion and plantarflexion. In addition, a posterior displacement of the COMx in eversion compared to plantarflexion in all MVIC percentages, with greater topographic distancing of the COMx at higher levels of activation. In conclusion, the peroneus longus muscle presented NMCs; the anterior compartment contributed to both eversion and plantarflexion movements, whereas the posterior compartment mainly contributed to the eversion movement of the ankle in low, moderate, and high percentages of MVIC.

The Role of the Acromioclavicular Ligament in Acromioclavicular Joint Stability: A Cadaveric Biomechanical Study

Background: Acromioclavicular (AC) joint dislocation is evaluated using the radiologically based Rockwood classification. The relationship between ligamentous injury and radiological assessment is still controversial. Purpose/Hypothesis: To investigate how the AC ligament and trapezoid ligament biomechanically contribute to the stability of the AC joint using cadaveric specimens. The hypothesis was that isolated sectioning of the AC ligament would result in increased instability in the superior direction and that displacement >50% of the AC joint would occur. Study Design: Controlled laboratory study. Methods: Six shoulders from 6 fresh-frozen cadavers were used in this study. Both the scapula and sternum were solidly fixed on a customized wooden jig with an external fixator. We simulated distal clavicular dislocation with sequential sectioning of the AC and coracoclavicular (CC) ligaments. Sectioning stages were defined as follows: stage 0, the AC ligament, CC ligament, and AC joint capsule were left intact; stage 1, the anteroinferior bundle of the AC ligament, joint capsule, and disk were sectioned; stage 2, the superoposterior bundle of the AC ligament was sectioned; and stage 3, the trapezoid ligament was sectioned. The distal clavicle was loaded with 70 N in the superior and posterior directions, and the magnitudes of displacement were measured. Results: The amounts of superior displacement averaged 3.7 mm (stage 0), 3.8 mm (stage 1), 8.3 mm (stage 2), and 9.5 mm (stage 3). Superior displacement >50% of the AC joint was observed in stage 2 (4/6; 67%) and stage 3 (6/6; 100%). The magnitudes of posterior displacement were 3.7 mm (stage 0), 3.7 mm (stage 1), 5.6 mm (stage 2), and 9.8 mm (stage 3). Posterior displacement >50% of the AC joint was observed in stage 3 (1/6; 17%). Conclusion: We found that the AC ligaments contribute significantly to AC joint stability, and superior displacement >50% of the AC joint can occur with AC ligament tears alone. Clinical Relevance: The AC ligament plays an important role not only in horizontal stability but also in vertical stability of the AC joint.

Lateral Tibial Plateau with Peroneal Nerve Entrapment is Unique Fracture in Diagnosis and Management

A majority of tibial plateau fractures involve the lateral plateau. Posterolateral tibial plateau fractures are caused by a valgus force that impacts the posterolateral plateau against the lateral femoral condyle. We describe a unique case of a patient who sustained a lateral plateau fracture with posterior displacement behind a fractured fibular head, with entrapment of the peroneal nerve. This unusual fracture pattern required dual anterolateral and lateral approach for reduction and fixation.

A Paleozoic stem hagfish Myxinikela siroka — revised anatomy and implications for evolution of the living jawless vertebrate lineages

Hagfishes and lampreys comprise cyclostomes, the earliest branching and sole surviving clade of the once diverse assemblage of jawless crown-group vertebrates. Lacking mineralized skeletons, both of the crown cyclostome lineages have notoriously poor fossil record. Particularly in the hagfish total group, †Myxinikela siroka Bardack, 1991 from the Late Carboniferous estuarine system of Illinois (USA) represents the only definitive stem taxon. Previously known from a single specimen, Myxinikela has been reconstructed as a short-bodied form with pigmented eyes but otherwise difficult to distinguish from the living counterpart. With a new, second specimen of Myxinikela reported here, I reevaluate the soft tissue anatomy and formulate diagnosis for the taxon. Myxinikela has a number of general features of cyclostomes, including cartilaginous branchial baskets, separation between the esophageal and the branchial passages, and a well-differentiated midline finfold. In effect, these features give more lamprey-like appearance to this stem hagfish than previously assumed. Myxinikela still has many traits that set modern hagfishes apart from other vertebrates (e.g., nasohypophyseal aperture, large velar cavity, and cardinal heart) and some intermediate conditions of modern hagfishes (e.g., incipient posterior displacement of branchial region). Thus, Myxinikela provides an important calibration point with which to date origins of these characters.