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To evaluate the effect of gingko biloba (EGb) on diethylstilbestrol (DES) induced testicle injury in mice. Fifty male mice were divided into a control group (A), DES group (B), and 3 EGb groups (C, D, E). The EGb-treated groups received peritoneal EGb at 8.75 (C), 17.5 (D), 35 mg/kg (E) BW daily for 7 days. The control group was given equivalent amount of normal saline. The mice in groups B, C, D and E were injected hypodermically with DES at 40 mg/kg BW daily 4 hours after the first herbal administration, while the control was given olive oil. Compared with DES group, the testis coefficients-relative testicular weight increased in the three EGb-treated groups. No significant difference was observed in epididymis coefficients. Lipid peroxidation status and antioxidant enzyme activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were significantly elevated in testes of EGb-treated groups. Lactate dehydrogenase (LDH) activities and malonaldehyde (MDA) contents were significantly decreased in testes of the EGb groups. The results indicate that EGb protects the testis from diethylstilbestrol-induced injury.

The author presents the case report of the rare for infant injury — the laceration of flexor pollicis longus tendon, which requires decisions on some complex questions relating to optimal tendon suture, suture material, type and duration of immobilisation, and the protocol for post-operative management.

Closed avulsion of the flexor digitorum profundus (FDP) tendon is classified based on the impact of injury on the management plan. In this report, we present a case with unclassified pattern of FDP tendon avulsion. The injury involves an intra-articular fracture of the volar part of distal phalanx of the little finger resulting into two bony fragments, one attached to the retracted avulsed tendon and another separated and incarcerated at A4 pulley, and an intact dorsal cortex of the phalanx. Based on that, we recommend the development of a new classification scheme for this condition.

Background: Closed avulsion injury of the flexor digitorum profundus (FDP) tendon is a relatively common condition of the hand. Its present classification system seems to be deficient in including all possible patterns of injury, leading to improper selection of the best treatment method for the injury. We aim to provide a new classification scheme for this injury.

Methods: We developed a new classification scheme based on the possible pattern of FDP tendon injury. It consisted of three main types, and 10 sub-types. This was used to classify the injury of 34 patients, and help in choosing the best management approach. All patients underwent surgical treatment of their injury. The distal interphalangeal (DIP) joint extension deficit and total active motion (TAM) of the proximal interphalangeal (PIP) and DIP joints were considered as the main outcomes. Five orthopaedic surgeons used the new classification system for our cases, and the inter-rater reproducibility was tested with Fleiss' kappa.

Results: The multi-rater kappa for the classification was excellent. At the final follow-up visit 24 months following surgery, the mean loss of extension of the DIP joint was 13.76° ± 13.53° (range 0° to 45°), while the mean TAM was 148.88° ± 22.64° (range 94° to 172°). Based on the TAM score, 21 (61.76%), 8 (23.53%) and 5 (14.71%) patients had excellent, good and fair results, respectively. None of our patients had poor results.

Conclusions: Our new classification scheme of FDP tendon avulsion appeared to be comprehensive and useful in guiding the surgeon for the best treatment option. Nevertheless, this should be confirmed by using it for larger number of patients with different patterns of injury.

In this study, the biomechanical roles of disc nucleus and ligaments of human lower thoracic spine (T10–T12) under different loads were investigated using finite element (FE) method. The T10–T12 FE model was developed and validated against the published results. The FE model was then modified accordingly to simulate the injured conditions of nucleus, ligaments and facets and loaded under different configurations to analyze the segmental gross responses and the stress distribution around the annulus circumference. The high first-principal stress of annulus at the posterolateral region has an important role on the disc annulus's tear and a flexion moment causes a high first-principal stress at posterolateral region, despite of the existence of ligaments. The study also shows that decompression in intervertebral discs can reduce the dilatation of annulus tears by 18% around the posterolateral regions of disc annulus. The disc nucleus and the posterior ligaments have important roles in resisting compression and flexion loads, respectively. The investigations in this paper not only supplement experimental research but are also helpful in the understandings of biomechanics of lower thoracic spine.

A total of 116 surgically treated patients with unstable fractures of the thoracic and lumbar spines were subjected to this study on basis of the simple radiographic and CT findings of the injured spinal column and neurological changes at the injured cord and/or roots level. Among them 50 patients were paraplegics and 66 patients were non-paraplegics. Spine fracture patterns shown on axial CT images were classified into five types on the basis of the fracture severity of vertebral body associating the canal compromise by the encroached fracture fragments from middle column and posterior element. Type I: vertical linear fracture through mid-anterior and posterior elements; Type II: retropulsed fragment in the canal with intact posterior element; Type III: retropulsed fragment in the canal with fracture of the posterior element; Type IV: severe comminution of body and disruption of posterior element around the canal; Type V: fracture-dislocation of comminuted vertebral body and neural arch (with or without double margin sign and with or without vacant facet sign). Displacement of vertebral body on lateral plane radiograms showed significant difference ($p$ < 0.001) between the non-paralytics and paralytics, but there were no differences in kyphotic angles and anterior body height loss between the two groups. Neurological injury was highly complicated in cases of the fracture-dislocation (20 out of 22 patients: 90.9%). Unstable fracture which occurred in the thoracic level showed high incidence of neurological injuries [24 out of 28 patients (85.7%)]; complete paralysis in 20 (71.4%) out of 28 patients in comparison with that of the thoracolumbar and lumbar fractures. Anteroposterior (AP) diameter of the compromised neural canal and percentile surface area of the compromised canal showed significant differences between the paralytics and non-paralytics (canal diameter: $p$ < 0.05, canal compromise: $p$ < 0.05). Neural deficit was highly complicated in type IV and V fractures. In conclusion, it was found that clinical neurological assessment and CT-based fracture classification were the valid approaches in managing the fractured spine.

Purpose: Our study aimed to find the location and pattern of musculoskeletal injuries in participants enrolled in Zumba-based training and to analyze the contributing risk factors for injuries through a self-administered questionnaire. Methods: A total of 50 participants were recruited in an offline and online-based study using a self-administered questionnaire based on seven demographic-based questions, eight injury-related questions and five questions based on the risk factors related to Zumba-based training. Binomial logistic regression analysis was used to predict the odds-ratio and factors contributing to the risk of injuries. Results: Twenty-nine out of 50 participants (58%) had single or multiple musculoskeletal injuries with the most common sites of injury being in the order of: leg (23%), knee (18%) and ankle, foot and the lower back (15%). Amongst the injured subjects, 10 (34.4%) had sought medical help and 11 (37.9%) had resorted to self-management. The binomial regression analysis showed the presence of recurrent injuries and the flooring of the class to be significantly associated with the risk of injuries. Conclusion: There was a 58% prevalence of musculoskeletal injuries in the subjects enrolled in Zumba-based training. The factors which are found to be an increased risk for musculoskeletal injuries were recurrent injuries and flooring of the class.

An advanced shear lag model is developed to analyze the stress-shielding effect in injured muscle fiber by introducing the activation strain. The model considers three muscle fibers connected by the endomysium with the middle muscle fiber injured. Stress shielding describes the function of the lateral transmission of force in protecting the injured muscle fibers from being further injured by transferring force in the injured muscle fiber to its adjacent muscle fibers. Parameter studies demonstrate that the mechanical and geometrical properties of muscle fibers and the endomysium as well as the degree of injury can affect the stress-shielding effect. In conclusion, the model successfully demonstrates and captures, at least in a qualitative manner, the lateral transmission of force between an injured and a normal muscle fiber.

The occupant's pelvis is most susceptible to injuries in side collision accidents. To further investigate the pelvis biomechanical responses and injury mechanisms in side impacts, a biofidelic pelvis finite element (FE) model was created. In contrast to previous studies, the model was based directly on the CT data of a volunteer representing the 50th percentile Chinese male. Both cortical and cancellous bone were modeled with hexahedral elements. Through model validations against Post Mortem Human Subjects (PMHS) tests, the pelvis responses and injuries under side impacts were analyzed. Meanwhile, additional simulations were carried out utilizing the validated model to study the effects of the femoral head, impactor pad and impactor velocity on pelvic injuries. The results indicated that the most frequent injury type of the pelvis is pubic rami fracture, followed by fractures of the femoral head, greater trochanter and acetabulum. In validation against the test of Guillemot et al., the critical load of pelvic fracture was 3.8 kN. In validation against the tests of Beason et al., the peak impact force under unpadded load and padded load was 4.3 kN and 3.1 kN, respectively, while the (VC)_max was 0.25 m/s and 0.16 m/s, respectively. Peak impact force appears to be a reasonable criterion to assess pelvic injury. Moreover, the femoral head and impactor pad play an important role in absorbing impact energy, distributing impact load, and alleviating pelvic injury.

Stress fracture of the metatarsal (MT) is often reported clinically. This study was aimed to measure and compare the three-dimensional (3D) morphological structure of five MTs, and investigate the in vitro biomechanics of five MTs under simulated stance phase. A total of seven foot-ankle samples of human cadavers were collected for this experiment. All samples were CT-scanned and 3D re-constructed for digital measurements. To simulate the stance phase, each sample was vertically loaded with 700-N through a material testing machine. The 3D-reconstruction-based measurement showed significant differences of the shaft length, vertical height, and inclination angle between the second MT and four others. Experimental strain measurements at dorsal MTs along the principal axis are all compressive. The values are respectively $-63.99\pm 17.86$, $-123.54\pm 18.07$, $-143.16\pm 24.75$, $-25.48\pm 9.16$, and $-61.56\pm 19.52$ micro-strain from the first to fifth MTs. This study proposed a new load condition of plantar-flexed simply supported beam to describe the MT loading mechanism. The second and third MTs have higher risk of stress fracture due to combined effects of inhomogeneous load distribution, unfavorable geometry and structure, and limited joint motion. This finding would be helpful for design of protective equipment.

Hepatic injury induced by blunt abdominal impact is a major cause of death in vehicle crashes. However, few works have been done effectively in cadaver experiments to clarify the liver’s specific dynamic behavior and mechanical characteristics. This paper described the dynamic behavior and mechanical characteristics of the liver under blunt impacts to the upper abdomen with the finite element model (FEM) of the Chinese human body — the 50 percentile-sized male (CHUBM-M50). The simulation matrix, three directions (frontal, oblique, lateral), and four speeds included in each group were designed with a 23.4kg, rigid cylindrical impactor aligning the T11 level. The liver deformation contours displayed compression against the spine and rotation in the horizontal plane, which were the two main features in liver motion. Pressure distribution in the liver capsule and parenchyma was discussed to elucidate the biomechanical characteristics related to impact direction. Generally, the stress distribution in the capsule was 10 times higher than that in the parenchyma. A discussion of the injury mechanism of the liver capsule and parenchyma observed in the simulations was given upon the pressure distribution. It demonstrated that the capsule could protect liver parenchyma at low-speed impacts and should not be neglected for understanding liver injury mechanisms.

In this paper, a three-dimensional material point human head model is constructed from the computed tomography (CT) scanned images of an adult male volunteer, and used to study the dynamic response of human head under the impact of a three-dimensional cylindrical lead projectile with a speed of 6.4 m/s. The model consists of skull bone, brain tissue and membrane of human head, which is close to the real one. The skull and membrane are modeled by an elastic constitutive model, and the brain tissue is modeled by an anisotropic viscoelastic constitutive model. These constitutive models have been implemented in our three-dimensional explicit material point method code, MPM3D, and is verified by comparing its numerical results for a ball impact problem with those obtained by LS-DYNA. The simulation results help illustrate the response of skull bone, membrane and brain tissues subjected to impact, which contributes to the understanding of the biomechanics and mechanisms of head injury.

Background: The increasingly fashionable sport of motocross is practiced worldwide by millions of people, but there is very little in the literature regarding its associated injuries and their prevention. We therefore present the first comprehensive, prospective study looking at hand and wrist injuries resulting from motocross injuries in the UK.

Methods: Data was prospectively collected over a 5-year period (from 2010 to 2015) at our regional trauma unit. We exclusively looked at motocross riders. Injuries sustained via motorcycle were excluded from our study.

Results: During the period studied (five years), 615 injuries were collected, including 240 patients with 265 hand and wrist injuries. Most of injuries were sustained in male patients. The patient’s age range was from 4–78 years with most injuries occurring during the spring and summer months. A total of 96 (40%) patients required operative treatment. The most common injury pattern was distal radius fractures (n = 53, 20%), followed by metacarpal fractures (n = 38, 14%) and phalangeal fractures (n = 36, 13.5%).

Conclusions: This study shows the impact and incidence of related hand and wrist injuries. Motocross is a globally fashionable sport. This study shows that the number of annual tournaments and racers have doubled in last 5 years. The number of hand and wrist related injuries and operative requirements have quadruples over the last five years. It is recognized as a high-risk sport despite the use of protective equipment and course adaptions. These injuries can have implications for nearby treating hospitals.

Paediatric hand fracture care presents unique considerations and challenges. The proximal phalanx is the most injured location. This review details pearls for the examination of the injured paediatric hand, immobilisation considerations and treatment strategies. Over-treatment can lead to unnecessary stiffness, missed activities, increased healthcare costs or unnecessary surgical morbidity. Undertreatment can promote malunion and dysfunction. Fracture patterns discussed include those of the phalangeal head, neck, shaft and base. The concepts covered will help optimise the evaluation and treatment of children with injured proximal phalanges.

Level of Evidence: Level V (Therapeutic)

Background: Upper limb traumatic injuries have a significant impact on social and professional life; however, there is still a paucity of studies focusing on the injuries of the ulnar border of the forearm, wrist and hand.

Methods: We designed a retrospective single-blinded study, including all patients with deep traumatic wounds affecting the ulnar side of the forearm, wrist or hand, that received surgical treatment from 2006 until 2016. A characterisation of the sample, assessment of concomitant injuries and clinical outcomes, as well as neurological and functional evaluation were performed.

Results: We obtained a sample of 61 patients, 69% with injuries affecting the wrist and 90% of patients with a neurological lesion, most frequently of the ulnar nerve lesion (UNL). Concomitant injuries included tendinous lesions, more frequently of the flexor carpi ulnaris (64%) and fractures (13%). And 39% of patients presented an ulnar artery lesion, without significant differences in outcomes regarding the completion of arteriorrhaphy or not. At the end of the 8.6 years follow-up, 34% of patients had no deficits; however, patients with UNL showed worse functional scores and greater risk of sequelae. Besides motor function compromise, sensory deficits were also associated with worst functional outcomes.

Conclusions: The UNL subgroup showed important impairment of the first ray, probably related to the level of UNL. Furthermore, besides the implications of the motor sequelae, sensory deficits were also associated with worst functional scores. Due to the high percentage of neurovascular and tendinous lesions in ulnar-sided upper extremity wounds, the authors recommend surgical exploration of these lesions.

Level of Evidence: Level IV (Therapeutic)

Electrical stimulation has been integrated in recent decades into rehabilitation protocols following neuromuscular injuries. Existing literature supports the utilisation of prolonged or continuous stimulation generated by implantable or transcutaneous devices for chronic pain subsidence and muscle trophism maintenance, which improve outcomes following microsurgical interventions. Newer uses include brief electrical stimulation for peripheral nerve injury. Brief electrical stimulation has shown promise in expediting regeneration of both torn and crushed nerve axons in the murine model and has been incorporated into a limited number of clinical studies. Augmentation of the natural response of an injured peripheral nerve by electrical stimulation has the potential to accelerate regeneration, presumably leading to improved function and clinical outcomes. We review the existing literature on intraoperative utilisation of electrical stimulation to enhance regeneration, such as neural mechanisms of action and their microscopic effect in animal models, as well as results from initial human studies.

Level of Evidence: Level V (Therapeutic)

Construction workers globally face disproportionate threats to health and wellbeing, constituted by the nature of the work they perform. The workplace fatalities and lost-time injuries experienced by construction workers are significantly greater than in other forms of work. This paper draws on the culture-centered approach (CCA) to dialogically articulate meanings of workplace risks and injuries, voiced by Bangladeshi migrant construction workers in Singapore. The narratives voiced by the participants suggest an ecological approach to workplace injuries in the construction industries, attending to food insecurity, lack of sleep, transportation, etc. as contextual features of work that shape the risks experienced at work. Moreover, participant voices point to the barriers in communication, lack of understanding, and experiences of incivility as features of work that constitute the ways in which they experience injury risks. The overarching discourses of productivity and efficiency constitute a broader climate of threats to worker safety and health.

The physiological role of metallothionein (MT) has been a topic of growing interest, particularly with regard to a potential therapeutic application in trauma of the central nervous system (CNS). An increasing number of studies describe the protective, regenerative, and anti-inflammatory properties of MT-I and MT-II isoforms (MT-I/MT-II) in the context of in vitro and animal models, using, for example, MT-I/MT-II null, overexpressing, or injected mice following induced CNS trauma or disease. MT-I/MT-II respond to trauma by upregulation, and may have roles in metal ion homeostasis and free radical scavenging. Notably, a direct action of MT-I/MT-II on neurons has been shown using in vitro models, whereby the application of exogenous MT-I/MT-II directly increases neurite outgrowth of young neurons and regeneration of injured, mature neurons. The expression and putative functions of MT within the injured CNS will be addressed within this chapter, with particular regard to the MT-I/MT-II isoforms that display neuroprotective and regenerative properties. Intriguingly, a further member of the MT family, MT-III, shows high homology to MT-I/MT-II, yet has a contrasting effect on neuron growth and survival in some models.