The Effects of Various Cognitive Tasks Including Working Memory, Visuospatial, and Executive Function on Postural Control in Patients With Anterior Cruciate Ligament Injury.

Anterior cruciate ligament (ACL) rupture can impair balance performance, particularly during cognitive motor dual-tasks. This study aimed to determine the effects of various modalities of cognitive load (working memory, and visuospatial and executive function) on postural control parameters in individuals with ACL injury. Twenty-seven ACL-injured and 27 healthy participants were evaluated doing different cognitive tasks (silent backward counting, Benton's judgment of line orientation, and Stroop color-word test) while standing on a rigid surface or a foam. Each task was repeated three times and then averaged. Center of pressure variables used to measure postural performance included sway area and sway velocity in anterior-posterior and medial-lateral directions. Cognitive performance was also assessed by calculating errors and the score of cognitive tasks. A mixed model analysis of variance for center of pressure parameters indicated that patients had more sways than the healthy group. The interaction of group by postural difficulty by cognitive tasks was statistically significant for cognitive errors (p < .01), and patients with ACL injury indicated more cognitive errors compared to healthy controls while standing on the foam. The main effect of cognitive task was statistically significant for all postural parameters, representing reduced postural sways in both groups with all cognitive tasks. However, ACL-injured patients showed more cognitive errors in difficult postural conditions, suggesting that individuals with ACL injury may prioritize postural control over cognitive task accuracy and adopt the posture-first strategy to maintain balance under dual-task conditions.

Investigation of background, novelty and recent advance of iron (II,III) oxide- loaded on 3D polymer based scaffolds as regenerative implant for bone tissue engineering: A review.

Bone tissue engineering had crucial role in the bone defects regeneration, particularly when allograft and autograft procedures have limitations. In this regard, different types of scaffolds are used in tissue regeneration as fundamental tools. In recent years, magnetic scaffolds show promising applications in different biomedical applications (in vitro and in vivo). As superparamagnetic materials are widely considered to be among the most attractive biomaterials in tissue engineering, due to long-range stability and superior bioactivity, therefore, magnetic implants shows angiogenesis, osteoconduction, and osteoinduction features when they are combined with biomaterials. Furthermore, these scaffolds can be coupled with a magnetic field to enhance their regenerative potential. In addition, magnetic scaffolds can be composed of various combinations of magnetic biomaterials and polymers using different methods to improve the magnetic, biocompatibility, thermal, and mechanical properties of the scaffolds. This review article aims to explain the use of magnetic biomaterials such as iron (II,III) oxide (Fe2O3 and Fe3O4) in detail. So it will cover the research background of magnetic scaffolds, the novelty of using these magnetic implants in tissue engineering, and provides a future perspective on regenerative implants.

Fabrication of an Artificial Pulley Based on Electrospun Composite Polyurethane/Polycaprolactone Nanofibers for Hand Surgery: Structural, Mechanical, In Vitro, and In Vivo Examinations.

Injuries to the hand's flexor pulley system can be debilitating, causing pain and restricting movement of the affected finger(s). The creation of a biocompatible artificial pulley could potentially alleviate some of the complications associated with current surgical treatments. In this study, a biocompatible artificial pulley was fabricated by using polycaprolactone (PCL) and polyurethane (PU) in the form of an electrospun nanofiber structure. All scaffolds were structurally analyzed using FESEM imaging, porosity, FTIR, and DSC examinations. Mechanical properties were evaluated, and in vitro studies were conducted on the degradation rate, swelling ratio, and toxicity. Immune response to fabricated scaffolds was evaluated by implanting them under the skin of rats for further pathological examination. All scaffolds exhibited a nanoscale structure and high porosity without any undesirable functional groups. The 25% PCL scaffold showed 17%, 20%, 80%, 17%, and 70% significant increases in Fmax, final stress, final strain, Young's modulus, and elongation percentage, respectively. In fact, the PCL25% scaffold demonstrated more than 100% improvement in mechanical properties compared to those of A2 and A4 natural pulleys. Additionally, all scaffold structures showed cell viability similar to that of the control sample. The study suggests that scaffolds made of 25% PCL hold promise as effective artificial pulleys for reconstructing the flexor tendon pulley system in cases of injury.

Exosomes and Nano-SDF Scaffold as a Cell-Free-Based Treatment Strategy Improve Traumatic Brain Injury Mechanisms by Decreasing Oxidative Stress, Neuroinflammation, and Increasing Neurogenesis.

Traumatic brain injury (TBI) causes a variety of complex pathological changes in brain parenchymal tissue by increasing neuroinflammatory and apoptosis responses. Currently, there is no treatment to resolve the consequences related to TBI. Recently, an extensive literature has grown up around the theme of bystander effects of stem cells, a mechanism of stem cells without the need for cell transplantation, which is called cell-free therapy. The purpose of this investigation was to determine the efficacy of a cell-free-based therapy strategy using exosomes derived from human neural stem cells (hNSCs) and a novel nano-scaffold in rats subjected to TBI. In this study, a series of in vitro and in vivo experiments from behavior tests to gene expression was performed to define the effect of exosomes in combination with a three-dimensional (3D) nano-scaffold containing a bio-motif of SDF1α (Nano-SDF). Application of exosomes with Nano-SDF significantly decreased oxidative stress in serum and brain samples. Moreover, treatment with exosomes and Nano-SDF significantly reduced the expression of Toll-like receptor 4 and its downstream signaling pathway, including NF-kß and interleukin-1ß. We also found that the cell-free-based therapy strategy could decrease reactive gliosis at the injury site. Interestingly, we showed that exosomes with Nano-SDF increased neurogenesis in the sub-ventricular zone of the lateral ventricle, indicating a bio-bridge mechanism. To sum up, the most obvious finding to emerge from this study is that a cell-free-based therapy strategy can be an effective option for future practice in the course of TBI.

Additively manufactured porous scaffolds by design for treatment of bone defects.

There has been increasing attention to produce porous scaffolds that mimic human bone properties for enhancement of tissue ingrowth, regeneration, and integration. Additive manufacturing (AM) technologies, i.e., three dimensional (3D) printing, have played a substantial role in engineering porous scaffolds for clinical applications owing to their high level of design and fabrication flexibility. To this end, this review article attempts to provide a detailed overview on the main design considerations of porous scaffolds such as permeability, adhesion, vascularisation, and interfacial features and their interplay to affect bone regeneration and osseointegration. Physiology of bone regeneration was initially explained that was followed by analysing the impacts of porosity, pore size, permeability and surface chemistry of porous scaffolds on bone regeneration in defects. Importantly, major 3D printing methods employed for fabrication of porous bone substitutes were also discussed. Advancements of MA technologies have allowed for the production of bone scaffolds with complex geometries in polymers, composites and metals with well-tailored architectural, mechanical, and mass transport features. In this way, a particular attention was devoted to reviewing 3D printed scaffolds with triply periodic minimal surface (TPMS) geometries that mimic the hierarchical structure of human bones. In overall, this review enlighten a design pathway to produce patient-specific 3D-printed bone substitutions with high regeneration and osseointegration capacity for repairing large bone defects.

Nanofibrous polycaprolactone/chitosan membranes for preventing postsurgical tendon adhesion.

Peritendinous adhesion is considered a major postsurgical tendon complication in hand surgery. This complication could be mitigated partially through early tendon mobilization. However, development of new treatment modalities to guide tissue regeneration and to reduce postsurgical tendon adhesion has recently gained attentions. In this article, synthesis and characterization of electrospun nanofibrous membranes (NFMs) of polycaprolactone (PCL) and chitosan to form a physical barrier against cellular migration leading to tendon adhesion is presented. The mechanical properties of the NFMs are modulated to maintain high integrity during postsurgical tendon mobilization. The tensile strength of the NFMs is examined in wet and dry conditions after 1000 cyclic pull loadings. In addition, the mechanical strength of the NFMs is evaluated after a degradation period of 30 days. To obtain NFM with desired properties, concentrations of polymer solutions, operation parameters of electrospinning and the thickness of NFMs were optimized. Based on the biodegradation and mechanical evaluations, the optimum NFM was obtained for specified amounts of PCL (5 wt %) + chitosan (2 wt %) at an electrospinning drum speed of 400 rpm. The engineered NFM could withstand forces of 33 and 19 N before and after 1000 pull cycles that are sufficient during tendon healing process. The bonding of chitosan fibers over PCL nanofibers allowed for production of NFMs with appropriate mechanical integrity and degradation rate. In vitro cell culture tests demonstrated that PCL/chitosan could only have minor impact on decreasing fibroblast attachment over the membranes probably due to protonation of amine groups.

Biomechanical evaluation of intraosseous distal radioulnar joint prosthesis: A prosthesis designed based on Sauvé-Kapandji procedure.

INTRODUCTION: To avoid the DRUJ surgical procedures disadvantages, a new intraosseous distal radioulnar prosthesis designed on Sauvé-Kapandji procedure has been introduced. Stability of the prosthesis and biomechanics are to be evaluated in this article. MATERIALS AND METHODS: On a cadaveric study, during placement of the prosthesis, biometry of the bones, prosthesis stability (in axial and lateral tractions, wrist pronation and supination, and squeeze test), wrist range of motion before and after implantation, and radiographic evaluation were done on 16 cadavers. RESULTS: Range of motion of the wrist joint before and after the insertion of the prosthesis, had no significant difference in all six directions. Stability of the prosthesis, when rotational pronation force was exerted, was greater than when rotational supination force was exerted. The prosthesis showed significant stability against longitudinal traction forces in a way that no prosthesis dislocation was observed up to 150N forces. Stability of the prosthesis was investigated when lateral force was applied to different wrist positions. The most stable position of the prosthesis was in the case of lateral traction forces in supination where no case of dislocation was observed. CONCLUSIONS: The intraosseous distal radioulnar prosthesis demonstrated stable structure with no effect on wrist range of motion. LEVEL OF EVIDENCE: IV.

3D printing-assisted fabrication of a patient-specific antibacterial radial head prosthesis with high periprosthetic bone preservation.

We present a novel fabrication and surgical approach for anatomical reconstruction of a fractured radial head using a patient-specific radial head prosthesis (RHP) made of polymethylmethacrylate (PMMA) bone cement. To this end, the use of PMMA bone cement for prosthesis fabrication was initially investigated using computational modeling and experimental methods. The RHP was fabricated through casting of PMMA bone cement in a silicone mold in the operating room before implantation. To enhance the precision of bony preparation for replacement of the radial head, a patient-specific surgical guide for accurate resection of the radial neck with the desired length was developed. Post-surgical clinical examinations revealed biomechanical restoration of elbow function, owing to the use of the patient-specific RHP and surgical guide. Importantly, follow-up radiographs after a mean follow-up of 18 months revealed bone preservation at the bone-prosthesis interface without any signs of erosion of the capitellum. Taken together, our method demonstrated the safety and efficacy of the PMMA RHP in restoring elbow biomechanics. This also provides a very safe and cost-effective method for making various patient-specific prostheses with localized antibacterial delivery and close mechanical properties to native bone for improved periprosthetic bone regeneration. The clinical trial of this study was registered at Mashhad University of Medical Sciences under the trial registration number 970493.

Introduction and Early Outcomes of Intraosseous Distal Radioulnar Joint Prosthesis: A Pilot Study and a Technique on a New Design of the Sauvé-Kapandji Procedure.

BACKGROUND: Different surgical procedures have been proposed for the treatment of Distal Radioulnar Joint (DRUJ) arthrosis and other conditions. This study aimed to introduce a new design of DRUJ prosthesis based on the Sauvé-Kapandji procedure followed by the evaluation of its short-term results. Darrach and Sauvé-Kapandji techniques are two well-known salvage procedures. Various implant designs have been proposed for DRUJ substitution to avoid the disadvantages of these procedures. METHODS: Before and after the insertion of the intraosseous DRUJ prosthesis in five patients, indices, such as the range of motion, as well as grip and pinch strengths were measured and recorded. Moreover, the patients were asked to complete three questionnaires (i.e., Quick-Disabilities of the Arm, Shoulder and Hand; Visual Analogue Scale-Pain; and Patient-Rated Wrist Evaluation). RESULTS: The patients were followed up for 27.6 months. It is worth mentioning that all patients completed the follow-up period with no complication, except for one case who came with dislocation secondary to forearm malunion and proximal forearm impingement. According to the results, there were improvements in all indices, compared to pre- operation. CONCLUSION: The intraosseous distal radioulnar prosthesis can be an alternative option for the replacement of DRUJ.

Electrospun Nanofibrous Membranes for Preventing Tendon Adhesion.

Tendon injuries are frequent, and surgical interventions toward their treatment might result in significant clinical complications. Pretendinous adhesion results in the disruption of the normal gliding mechanism of a damaged tendon, painful movements, and an increased chance of rerupture in the future. To alleviate postsurgical tendon-sheath adhesions, many investigations have been directed toward the development of repair approaches using electrospun nanofiber scaffolds. Such methods mainly take advantage of nanofibrous membranes (NFMs) as physical barriers to prevent or minimize adhesion of a repaired tendon to its surrounding sheath. In addition, these nanofibers can also locally deliver antiadhesion and anti-inflammatory agents to reduce the risk of tendon adhesion. This article reviews recent advances in the design, fabrication, and characterization of nanofibrous membranes developed to serve as (i) biomimetic tendon sheaths and (ii) physical barriers. Various features of the membranes are discussed to present insights for further development of repair methods suitable for clinical practice.

Wound Healing and Antimicrobial Effects of Chitosan-hydrogel/Honey Compounds in a Rat Full-thickness Wound Model.

INTRODUCTION: Honey and chitosan have shown antimicrobial and wound healing effects. As a biocompatible and biodegradable biomaterial, chitosan has shown antimicrobial capabilities. OBJECTIVE: In this study, the effects of the incorporation of high molecular weight chitosan hydrogel on antibacterial, antifungal, and wound healing properties of honey were investigated. MATERIALS AND METHODS: The minimum inhibitory concentration of chitosan and honey were examined in pure and 3:1, 1:1, and 1:3 (v/v) compound ratios for Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. In addition, the inflammatory, granulation and fibrotic tissue formation, reepithelialization indices, and wound shrinkage effects of each treatment were evaluated and compared with saline and silver sulfadiazine. RESULTS: Chitosan/honey 1:3 was found to be effective against all 5 aforementioned germs. Honey, chitosan/honey 1:1, and chitosan/honey 1:3 showed faster wound healing and shrinkage effects. CONCLUSIONS: Incorporation of chitosan hydrogel into honey can substantially enhance its antimicrobial and wound healing effects. Chitosan-hydrogel/honey (1:3) is an optimal wound dressing formulation with ample antimicrobial and healing properties.

Micro and nanotechnologies for bone regeneration: Recent advances and emerging designs.

Treatment of critical-size bone defects is a major medical challenge since neither the bone tissue can regenerate nor current regenerative approaches are effective. Emerging progresses in the field of nanotechnology have resulted in the development of new materials, scaffolds and drug delivery strategies to improve or restore the damaged tissues. The current article reviews promising nanomaterials and emerging micro/nano fabrication techniques for targeted delivery of biomolecules for bone tissue regeneration. In addition, recent advances in fabrication of bone graft substitutes with similar properties to normal tissue along with a brief summary of current commercialized bone grafts have been discussed.

Iranian Joint Registry (Iranian National Hip and Knee Arthroplasty Registry).

Periodic evaluation and monitoring the health and economic outcome of joint replacement surgery is a common and popular process under the territory of joint registries in many countries. In this article we introduce the methodology used for the foundation of the National Iranian Joint Registry (IJR) with a joint collaboration of the Social Security Organization (SSO) and academic research departments considering the requirements of the Iran's Ministry of Health and Education.

Minimally invasive modified latarjet procedure in patients with traumatic anterior shoulder instability.

BACKGROUND: Despite recent advances in arthroscopic soft tissue repair and reconstruction for shoulder instability, Latarjet procedure is continuously a method of choice for many cases of unstable shoulders. OBJECTIVES: To evaluate the clinical results of minimally invasive modified Latarjet technique in recurrent, traumatic anterior shoulder instability associated with obvious Hill-Sachs and Bankart lesions. PATIENTS AND METHODS: Between 2007 and 2013, 36 consequent patients with traumatic anterior shoulder instability who underwent modified Latarjet operation were enrolled in this prospective study. The MRI studies revealed labrum detachment and Hill-Sachs lesion in all shoulders. For all patients, demographic and injury data were obtained and Constant Shoulder score, Rowe score, and UCLA scores were completed by related surgeon. Stability of the shoulder was assessed with the Jobe's relocation test preoperatively. The patients were followed up at two weeks, one month, three months, and six months from the date of the surgery and evaluated for probable complications. Above mentioned assessments were completed again at the time of the final follow-up. RESULTS: The average age of the enrolled patients was 24.6 (ranging from 18 to 33 years) and 35 patients out of the total of 36 patients were males. Motor-vehicle accidents were the major cause of the injuries (52%) with the average interval between the injury and operation of 3.1 ± 1.2 years (Ranging from 1 to 5 years). The average number of incidents of dislocations between the injury date and the surgery was 7.2 ± 2.1 (Ranging from 4 to 20). The average follow-up period was 37 months (Ranging from 12 to 65 months). All patients had Jobe's relocation test (Apprehension sign) pre-operatively and negative Jobe's relocation test post-operation. Significant improvements in functional scores were demonstrated postoperatively compared to preoperational assessment in all cases. Final follow up radiographs showed union of all the grafts and patients reported no incidents of re-dislocation during the follow-up period. One incidence of a superficial infection 2 weeks post operation was the only complication in this study. The infection was resolved with antibiotic treatment. CONCLUSIONS: The Latarjet procedure demonstrated good or excellent short-term outcomes in management of patients with traumatic, recurrent anterior shoulder dislocation with a low level of post-operative complication risks.

Validation and cross-cultural adaptation of the Persian version of Craig Handicap Assessment and Reporting Technique (CHART) short form.

OBJECTIVE: To test the psychometric specifications of the Persian version of the Craig Handicap Assessment and Reporting Technique (CHART) short form in an Iranian population. DESIGN: Cross-sectional study. SUBJECTS: Fifty-two individuals with a mean age of 49.3 years (SD 7.9, minimum 38 years and maximum 80 years), who had chronic spinal cord lesions, were included in this study. Most of them were paraplegic (88.5%) and unemployed (76.9%). METHODS: Reliability (internal consistency) of the measure was examined by applying Cronbach's alpha. In addition, validity (construct) was tested by Pearson's correlation. RESULTS: Overall, the internal consistency of the questionnaire was found to be satisfactory (Cronbach's alpha 0.613). Regarding construct validity, the minimum and maximum significant correlations were among Physical Component Summery and Cognitive Independence (r = 0.267, p < 0.05), Vitality and Social Integration (r = -0.429, p < 0.01) respectively. CONCLUSION: By analyzing data regarding the psychometric specifications of the Persian version of CHART, we can conclude that this version is a valid, reliable and unique measure that can be used for spinal cord-injured individuals. As demonstrated in our preliminary study, it is easy to be filled out and is not confusing. Implications for Rehabilitation The Persian version of the CHART has been successfully validated. It can be used by those working specifically in the field of spinal cord injury and also more generally. It will enable both initial assessment and follow-up for people in Persian-speaking areas of the world.

Quality of life and the related factors in spouses of veterans with chronic spinal cord injury.

BACKGROUND: The quality of life (QOL) of caregivers of individuals with chronic spinal cord injuries may be affected by several factors. Moreover, this issue is yet to be documented fully in the literature. The purpose of this study was to evaluate the health related quality of life of spouses who act as primary caregivers of veterans with chronic spinal cord injuries in Iran. METHODS: The study consisted of 72 wives of 72 veterans who were categorized as spinal cord injured patients based on the American Spinal Injury Association (ASIA) classification. Health related quality of life was assessed by the Short Form (SF-36) Health Survey. Pearson's correlation was carried out to find any correlation between demographic variables with SF-36 dimensions. To find the effect of the factors like age, employment status, duration of care giving, education, presence or absence of knee osteoarthritis, and mechanical back pain on different domains of the SF-36 health survey, Multivariate analysis of variance (MANOVA) was used. RESULTS: The mean age of the participants was 44.7 years. According to the ASIA classification 88.9% and 11.1% of the veterans were paraplegic and tetraplegic respectively. Fifty percent of them had a complete injury (ASIA A) and 85% of the spouses were exclusive care givers. All of the SF-36 scores of the spouses were significantly lower than the normal population. Pearson's correlation demonstrated a negative significant correlation between both age and duration of caring with the PF domain. The number of children had a negative correlation with RE and VT. CONCLUSION: The burden of caregiving can impact the QOL of caregivers and cause health problems. These problems can cause limitations for caregiver spouses and it can lead to a decrease in the quality of given care.

Concomitant ulecranon fracture, ipsilateral segmental humerus fracture and intercondylar humerus fracture in a 4-year-old girl: an extremely rare case report and literature review.

T-condylar fracture of distal humerus in young children is very rare. Pure physeal fractures of the olecranon are also rare. We report on an extremely rare case of concomitant ulecranon fracture, ipsilateral segmental humerus and intercondylar humerus fracture (type III) in a skeletally immature patient.

Isolated tuberculosis of the talus bone.

A 7-year-old boy was referred to us with a 3-month history of swelling and pain on his left ankle. On laboratory evaluation, he only had an elevated erythrocyte sedimentation rate. X-ray showed an extensive lytic lesion of the talus bone. Chest roentgenogram was normal. The Mantuex skin test was negative. Histological examination of the biopsy tissue showed granuloma and caseating necrosis of tuberculosis. Talectomy with 6 months of antituberculous chemotheraphy resulted in a good clinical outcome.