Traumatic Hip Dislocation: Pediatric and Adult Evaluation and Management.

Traumatic hip dislocation of a native hip joint represents an orthopaedic emergency that should be treated promptly. Dislocations can be classified based on the associated injuries and the direction of dislocation. Expeditious evaluation, reduction, and management of associated injuries are required to optimize short and long-term function of the hip. There are several important differences between the blood supply and ossification of the pediatric hip that necessitate different strategies for the evaluation and management of traumatic hip dislocations in pediatric patients. Appropriate treatment is dictated by the direction and type of dislocation as well as associated injuries. In addition to closed reduction, arthroscopy, open reduction (potentially with fracture fixation and/or soft-tissue repair), osteotomy, and total hip arthroplasty all have roles in treatment. Consensus on optimal postreduction activity protocols after simple hip dislocation remain unestablished. Short and long-term outcomes are largely driven by the amount of time from injury to reduction and associated injuries.

External Fixation Before Planned Conversion to Internal Fixation in Orthopaedic Trauma: Controversies and Current Trends.

External fixation is a widely used technique for a myriad of bone fractures and pathologies in all extremities. Despite its widespread use, controversies and unknowns still exist. This review article seeks to discuss current literature surrounding pin insertion technique, pin-site care, intraoperative use during conversion to definitive fixation, the relationship of pin sites to definitive fixation, and pin-site management after removal for temporary external fixation.

Plating Versus Intramedullary Nailing of OTA/AO 43C1 and C2 Intra-articular Distal Tibia Fractures: A Propensity Score and Multivariate Analysis.

OBJECTIVE: To compare rates of reduction loss, nonunion, and infection in intra-articular distal tibia fractures (IADTF) treated with limited open reduction internal fixation and intramedullary nailing (IMN) as compared to open reduction internal fixation with plate and screws (plate fixation [PF]). DESIGN: Retrospective review. SETTING: Level-I academic trauma center. PATIENT SELECTION CRITERIA: Patients age ≥ 18 with OTA/AO 43C1 and C2 IADTF treated with IMN or PF between 2013-2021. OUTCOME MEASURES AND COMPARISONS: Loss of reduction, surgical site infection (SSI), nonunion, and patient-reported outcomes (PROs) were compared for IMN versus PF treatments. RESULTS: One hundred ten patients met the inclusion criteria (IMN 33 and PF 77). There was no loss of reduction found. Seventeen nonunions (15% overall; IMN 4/33 and PF 13/77) and 13 SSIs (12% overall; IMN 2/33 and PF11/77) were identified. Despite several risk factors being identified for nonunion and SSI in bivariate analysis, only open fracture remained significant as a risk factor for both nonunion (odds ratio 0.09 for closed fracture, 95% confidence interval, 0.02-0.56, P = 0.009) and SSI (odds ratio 0.07 for closed fracture, 95% confidence interval, 0.06-0.26, P = 0.012) in the multivariate model. Propensity scoring based on presurgical variables was significantly different between patients who received IMN versus PF ( P = 0.03); however, logistic regression incorporating the propensity score revealed no significant association with nonunion and SSI. Adjusting for the propensity score, there remained no association comparing IMN versus PF with nonunion and SSI ( P = 0.54 and P = 0.17, respectively). There was also no difference in PROs between IMN and PF (physical function: P = 0.25 and pain interference: P = 0.21). CONCLUSIONS: Overall nonunion and SSI prevalence was 15% and 12%, respectively, in operatively treated OTA/AO 43C1 and C2 IADTF. An open fracture was a significant risk factor for nonunion and SSI. Metaphyseal fixation through IMN or PF did not affect loss of reduction, nonunion, SSI, or PROs. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Reliability of the Modified Radiographic Union Score for Tibia Fractures (mRUST) for Femoral Shaft Fractures.

OBJECTIVES: To evaluate the interobserver and intraobserver reliability of the modified Radiographic Union Score for Tibia Fractures (mRUST) and the effect of rater experience in evaluation of femoral fractures. DESIGN: Retrospective cohort study. SETTING: Single Level 1 trauma center. PATIENTS/PARTICIPANTS: Patients 18-55 years of age with a femur shaft fracture. INTERVENTION: Intramedullary nail fixation. MAIN OUTCOME MEASUREMENT: Interobserver and intraobserver reliability using the intraclass correlation coefficient. RESULTS: The overall interobserver reliability was 0.96. Among fellowship-trained evaluators, the interobserver reliability was 0.94, and it was 0.92 among trainees. The overall intraobserver reliability was 0.98. The intraobserver reliability was 0.97 among fellowship-trained evaluators and 0.96 for trainees. CONCLUSIONS: These results show high interobserver and intraobserver reliability of mRUST in the evaluation of radiographic healing for femur shaft fractures treated with intramedullary nail. This high reliability was further demonstrated throughout different postoperative healing time frames. In addition, mRUST appears to be reliable when used both by trainees and experienced surgeons for the evaluation of femur shaft fractures. LEVEL OF EVIDENCE: Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Clinical Assessments of Fracture Healing and Basic Science Correlates: Is There Room for Convergence?

PURPOSE OF REVIEW: The purpose of this review is to summarize the clinical and basic science methods used to assess fracture healing and propose a framework to improve the translational possibilities. RECENT FINDINGS: Mainstays of fracture healing assessment include clinical examination, various imaging modalities, and assessment of function. Pre-clinical studies have yielded insight into biomechanical progression as well as the genetic, molecular, and cellular processes of fracture healing. Efforts are emerging to identify early markers to predict impaired healing and possibly early intervention to alter these processes. Despite of the differences in clinical and preclinical research, opportunities exist to unify and improve the translational efforts between these arenas to develop and optimize our ability to assess and predict fracture healing, thereby improving the clinical care of these patients.

Results of Low Distal Femur Periprosthetic Fractures.

OBJECTIVES: To compare retrograde intramedullary nail (RIMN) and open reduction internal fixation (ORIF) in very distal periprosthetic distal femur fractures (PDFFs) to determine whether RIMN is an acceptable option for these fractures that are often considered too distal for IMN due to limited bone stock. DESIGN: Retrospective comparative series. SETTING: Level 1 trauma center. PATIENTS: Patients were treated with fracture fixation for a very distal PDFF, defined as the fracture extending to the anterior flange of the implant or distal. Fifty-six patients met inclusion criteria, with 8 excluded for less than 12 months of follow-up. INTERVENTION: The intervention involved fracture fixation with RIMN or ORIF. MAIN OUTCOME MEASUREMENTS: The primary outcome was unplanned return to surgery. Secondary outcomes included fracture union, radiographic alignment, visual analog score, and Patient-Reported Outcome Measurement Information System (PROMIS) Physical Function (PF) and Pain Interference. RESULTS: The mean follow-up period was 27 months. Twelve patients were treated with ORIF and 36 with RIMN. Twenty-one fractures were at the flange, and 27 extended distal to the flange. There were no differences between fixation methods for reoperation, deep infection, nonunion, malunion, visual analog score pain score, and PROMIS Pain Interference score. The mean PROMIS PF score was higher in the RIMN group compared with that in the ORIF group. There were 5 reoperations in the RIMN group (14%) and 3 in the ORIF group (25%). CONCLUSIONS: This is the largest series, to the best of our knowledge, of a subset of very distal PDFFs. The results suggest that RIMN may be an acceptable treatment option for these very difficult fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

A Modified Levine Approach for Exposure of the Anterior Column, Anterior Wall, and Sacroiliac Joint: A Surgical Technique and a Case Series.

SUMMARY: Surgical exposure of the anterior column, anterior wall, pelvic brim, and sacroiliac joint is accessible through the lateral window of the ilioinguinal approach. Residual attachment of the abdominal muscles and inguinal ligament to the anterior superior iliac spine (ASIS) is often a limiting factor to expanded distal and medial exposure, especially in patients with a large abdomen that hangs over the pelvis. An ASIS osteotomy has been described to improve exposure, particularly of the distal anterior wall and joint capsule, pubic ramus, and anterior quadrilateral plate. However, an ASIS osteotomy can be troublesome to reattach. In this study, we introduce a soft tissue release technique to mobilize the abdominal muscles and inguinal ligament to allow expanded surgical access to the distal anterior column/wall and sacroiliac joint and to create a working space for fracture reduction and fixation.

RNA-assisted self-assembly of monomeric antigens into virus-like particles as a recombinant vaccine platform.

Representing highly ordered repetitive structures of antigen macromolecular assemblies, virus-like particles (VLPs) serve as a high-priority vaccine platform against emerging viral infections, as alternatives to traditional cell culture-based vaccines. RNAs can function as chaperones (Chaperna) and are extremely effective in promoting protein folding. Beyond their canonical function as translational adaptors, tRNAs may moonlight as chaperones for the kinetic control of macromolecular antigen assembly. Capitalizing on genomic RNA co-assembly in infectious virions, we present the first report of a biomimetic assembly of viral capsids that was assisted by non-viral host RNAs into genome-free, non-infectious empty particles. Here, we demonstrate the assembly of bacterially-produced soluble norovirus VP1 forming VLPs (n = 180) in vitro. A tRNA-interacting domain (tRID) was genetically fused with the VP1 capsid protein, as a tRNA docking tag, in the bacterial host to transduce chaperna function for de novo viral antigen folding. tRID/tRNA removal prompted the in vitro assembly of monomeric antigens into highly ordered repetitive structures that elicited robust protective immune responses after immunization. The chaperna-based assembly of monomeric antigens will impact the development and deployment of VLP vaccines for emerging and re-emerging viral infections.

Tibial Fracture Healing Score: A Novel Tool to Predict Tibial Nonunion.

The aim of the study was to investigate the utility of a simple office-based tool in predicting the need for secondary intervention to obtain union in patients with tibial fractures. All patients 18 years and older with isolated tibial shaft fractures (OTA 41A, 42A-C, and 43A) treated with intramedullary nailing from 2013 to 2017 were screened. Eighty-seven patients met enrollment criteria. Surgeon assessment of the following 3 clinical parameters was performed at routine office visits and scored as follows: (1) pain (none/mild/decreased=1, no change/increased=0); (2) function (minimal limp/able to perform a single-leg stance=1, significant limp/unable to perform single-leg stance=0); and (3) examination (no/minimal pain with manipulation=1, pain with manipulation=0). Radiographic healing was assessed by the adjusted radiographic union scale in tibial fractures (aRUST). The tibial fracture healing score (TFHS) is the sum of 3 clinical scores (0 to 3) and aRUST score (1 to 3) at 3 months postoperatively. The overall nonunion rate was 11%. A RUST score of 5 or less and a sum of the 3 clinical scores of less than 2 at 3 months were found be predictive of nonunion. A TFHS of less than 3 at 3 months was more reliable in identifying patients requiring nonunion repair, especially for those with minimal radiographic healing (RUST score 6 or 7) at 3 months. The TFHS is a simple office-based clinical tool that may identify patients at high risk of nonunion (TFHS <3) following isolated tibial shaft fracture more effectively than clinical examination or radiographic assessment alone. [Orthopedics. 2020;43(4);e323-e328.].

Versatile biomimetic conductive polypyrrole films doped with hyaluronic acid of different molecular weights.

Electrically conductive polypyrrole (PPy) is an intriguing biomaterial capable of efficient electrical interactions with biological systems. Especially, biomimetic PPy-based biomaterials incorporating biomolecules, such as hyaluronic acid (HA), can impart the characteristic biological interactions with living cells/tissues to the conductive biomaterials. Here we report the effects of the molecular weight (MW) of HA on PPy-based biomaterials. We utilized HA of a wide range of MW (35 × 103 Da-3 × 106 Da) as dopants during the electrochemical production of PPy/HA films and their characterization of materials and cellular interactions. With increases in the MWs of HA dopants, PPy/HA exhibited more hydrophilic, higher electrochemical activity and lower impedance. In vitro studies revealed that PPy films doped with low MW HA were supportive to cell adhesion and growth, while PPy films doped with high MW HA were resistant to cell attachment. Subcutaneous implantation of the PPy/HA films for 4 weeks revealed that all the PPy/HA films were tissue compatible. We successfully demonstrate the importance of HA dopant MWs in modulating the chemical and electrical properties of the materials and cellular responses to the materials. Such materials have potential for various biomedical applications, including as tissue engineering scaffolds and as electrodes for neural recording and neuromodulation. STATEMENT OF SIGNIFICANCE: Hyaluronic acid (HA)-doped polypyrrole (PPy) films were electrochemically synthesized as novel biomimetic conductive materials capable of efficient electrical signaling and preferential biological interactions. Molecular weights (MWs) of HA varied in a wide range (35 × 103-2 × 106 Da) and critically determine chemical, electrochemical, and biological properties of PPy/HA. Especially, PPy films with low MW HA markedly support cell adhesion and growth, while PPy films with high MW HA are resistant to cell attachment. Furthermore, PPy/HA exhibits greatly improved tissue compatibility and in vivo EMG signal recording ability. We for the first time demonstrate that biomimetic PPy/HA-based biomaterials can serve as versatile and effective platforms for various biomedical applications, such as tissue engineering scaffolds and bioelectrodes.

The Aberrant Anterior Tibial Artery and its Surgical Risk.

Vascular injury to the popliteal artery during knee surgery is uncommon, but it has significant consequences not only for the patient but also to the surgeon since it poses the threat of malpractice litigation. The vascular anatomy of the lower extremity is variable especially when it involves both the popliteal artery and its branches. An aberrant vascular course may increase the risk of iatrogenic vascular injury during surgery. Careful preoperative planning with advanced imaging can decrease the risk of a devastating vascular injury.

Traumatic Hemipelvectomy with a Contralateral Unstable Pelvis and Acetabular Fracture: A Case Report and Review of the Literature.

CASE: A traumatic hemipelvectomy (THP) is a rare life-threatening injury, with limited reports in the civilian population. We present the case of a patient who sustained a massive pelvic injury with an incomplete unilateral THP, a contralateral unstable pelvis, and a fracture of the acetabulum. CONCLUSION: With advancements in resuscitative techniques, carefully timed and planned surgical interventions, and a coordinated multidisciplinary approach, a greater number of patients may be able to survive a massive pelvic injury.

Insertion-related pain with intramedullary nailing.

The use of intramedullary nails for the treatment of long bone fractures has become increasingly frequent over the last decade with gradually expanding indications and technological advances. Improved biomechanics relative to plates and less direct fracture exposure are some of the potential benefits of intramedullary nails. However, persistent insertion-related pain is common and may limit satisfactory long term outcomes. The etiologies of this phenomenon remain unclear. Proposed theories for which there is a growing body of supporting evidence include hardware prominence, suboptimal nail entry points leading to soft tissue irritation and structural compromise, local heterotrophic ossification, implant instability with persistent fracture micromotion, and poorly defined insertional strain. Many factors that lead to insertion-related pain are iatrogenic, and careful attention to detail and refined surgical techniques will optimize outcomes.

Electrochemical deposition of dopamine-hyaluronic acid conjugates for anti-biofouling bioelectrodes.

Bioelectrodes have been widely used to effectively mediate electrical signals with biological systems for various biomedical applications, such as biosensors and prosthetic probes. However, the electrical properties of bioelectrodes are frequently degraded in the biological milieu due to biofouling of bioelectrode surfaces. Hence, the development of simple and effective strategies for bioelectrode surface modification is important for the mitigation of biofouling. To this end, we electrochemically modify electrodes with dopamine-conjugated hyaluronic acid (DA-HA); the modified electrodes exhibit highly hydrophilic surfaces. In addition, the electrochemical impedance of the DA-HA-modified electrodes remains similar to those of bare electrodes. The DA-HA-modified electrodes showed reduced non-specific protein adsorption and minimal adhesion of fibroblasts. Our novel electrochemical passivation of electrodes using DA-HA will contribute to the further development of fouling-resistant and biocompatible bioelectrodes. The electrodeposition of DA-HA can also be potentially applied for general surface modification of other metallic and conducting materials for various applications.

Efficacy of single dose of a bivalent vaccine containing inactivated Newcastle disease virus and reassortant highly pathogenic avian influenza H5N1 virus against lethal HPAI and NDV infection in chickens.

Highly pathogenic avian influenza (HPAI) and Newcastle disease (ND) are 2 devastating diseases of poultry, which cause great economic losses to the poultry industry. In the present study, we developed a bivalent vaccine containing antigens of inactivated ND and reassortant HPAI H5N1 viruses as a candidate poultry vaccine, and we evaluated its immunogenicity and protective efficacy in specific pathogen-free chickens. The 6:2 reassortant H5N1 vaccine strain containing the surface genes of the A/Chicken/Korea/ES/2003(H5N1) virus was successfully generated by reverse genetics. A polybasic cleavage site of the hemagglutinin segment was replaced by a monobasic cleavage site. We characterized the reverse genetics-derived reassortant HPAI H5N1 clade 2.5 vaccine strain by evaluating its growth kinetics in eggs, minimum effective dose in chickens, and cross-clade immunogenicity against HPAI clade 1 and 2. The bivalent vaccine was prepared by emulsifying inactivated ND (La Sota strain) and reassortant HPAI viruses with Montanide ISA 70 adjuvant. A single immunization with this vaccine induced high levels of hemagglutination-inhibiting antibody titers and protected chickens against a lethal challenge with the wild-type HPAI and ND viruses. Our results demonstrate that the bivalent, inactivated vaccine developed in this study is a promising approach for the control of both HPAI H5N1 and ND viral infections.