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Rifles are often involved in violent deaths such as homicide and suicide. Consequently, expert knowledge and experimental forensic investigations are important to clarify the nature of ballistic trauma when applied to the human head and neurocranium. This study investigated differences in entrance wound morphology with Synbone® spheres which are described as being comparable to human flat bones. A series of ballistic experiments were conducted using two different rifle calibers (5.56 × 45 mm and 7.62 × 39 mm Full Metal Jacket (FMJ)). Synbone® spheres were used for close-range 0.3 m simulated executions as well as at 25 m and 35 m to simulate urban and military engagements. Results were compared with previously published experimental studies using similar military ammunition. In our study, entry wound morphology closely resembles real forensic cases compared to exit wound and overall shape morphology independently of the distance and the caliber. Circumferential delamination was clearly visible with full metal jacket (FMJ) rounds, yielding similar damage pattern morphology to the human crania. This study documented the presence of hydraulic burst or shock in all ten rounds from all three distances. Krönlein shots were also observed in some cases. Synbone® spheres constitute an acceptable synthetic surrogate for ballistic experiments. The present study offers new initial data on the behavior of Synbone® proxies in ballistic testing of military ammunitions; FMJ gunshot injuries to the human head, for distances that have not previously been published, suggesting that efficient tests can take place under these conditions. Further research on experimental ballistics with a larger number of controlled factors and multiple repetitions is recommended to verify the results of this pilot study before applied in forensic simulations.

A systematic review of the literature was carried out using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method to investigate the frequency of military thoracic gunshot wounds (GSWs) and deaths in combat theatres since World War Two (WW2). An electronic database search of World of Science, Scopus, Science Direct, PubMed and Microsoft Academic was conducted using the keywords ‘combat, casualties, thorax, gunshot, and military’ to identify peer-reviewed journals and conference papers on the topic. Twenty-three sources relevant to this review were identified and covered multiple theatres of operation. While there is a downward trend in the frequency of thoracic GSWs and fatalities likely due to the improvement of body armour, the improvement in medical treatment and increased frequency of improvised explosive devices (IEDs), the review shows that the advancement has not removed the likelihood of thoracic GSWs, which still accounted for approximately 15% of all thoracic injuries in the most recent combat theatres. The systematic review identifies that GSWs of the thorax continue to be a risk in military theatres and therefore, medical personnel should be aware of the frequency and severity of thoracic GSWs and should be prepared to treat these life-threatening injuries, as timely intervention is essential.

Forensic reconstructions and ballistic testing requires the use of consistent and repeatable simulants. Synthetic bone has been developed to be mechanically similar to human bone; however, it does not have the same viscoelastic properties. Bone acts as brittle and stiff material and fails instantly under high-energy events such as ballistic impacts. Consequently, bone simulants for use in ballistic testing should show comparable energy deposition to mammalian bones. This study aims to determine if Synbone® flat plates could be a viable proxy for Sus scrofa (domesticus) ribs in ballistic testing with 7.62 × 51 mm Full Metal Jacket ammunition. 5 mm, 6 mm and 12 mm quartered Synbone® plates were embedded into 10% ballistic gelatin and shot using 7.62 mm ammunition. The models were then analysed to compare the Synbone® to a previous Sus Scrofa (domesticus) rib study and focused on energy deposition, the number of fragments within the block, angle of deviation, onset of yaw, the temporary cavity, and the permanent wound channel. No significant difference was seen between the Sus Scrofa (domesticus) and the 5 mm Sybone®. There were significant differences observed between Sus Scrofa (domesticus) ribs and 6 mm Synbone® for the number of fragments, energy deposition and projectile tract diameter, and significant differences seen between Sus scrofa (domesticus) ribs and 12 mm Synbone® for the depth of onset of yaw, energy deposition and projectile tract diameter. This study indicates that the 5 mm Synbone® plate is a suitable proxy for Sus scrofa (domesticus) ribs for use with 7.62 × 51 mm FMJ ammunition in ballistic testing.

Background Postoperative analgesia after knee arthroplasty forms a basis for an optimal range of motion after surgery. Femoral nerve blocks are established as a sensory nerve blockade but at the expense of quadriceps weakness delaying postoperative mobilization. The adductor canal block (ACB) similarly provides sensory blockade but preserves quadriceps function. If ACB is performed intraoperatively, it would reduce the time and cost needed for ACBs. This study aimed at investigating possible landmarks making it feasible to perform ACB intraoperatively. Material and methods Twenty-seven knees were used. The superior pole of the patella, medial epicondyle, and adductor tubercle was proposed as landmarks to perform the ACB through a medial parapatellar approach. A needle was directed toward the adductor tubercle until a tactile feedback was felt. Ten to 15 mL India ink were injected using this technique. The adductor canal was dissected to visualize the ink spread and determine whether the saphenous nerve and the nerve to vastus medialis were exposed to the ink. Results The anatomic landmarks were easily identified in all knees. The ACB resulted in the saphenous nerve and nerve to vastus medialis being bathed in ink consistently. A volumetric relationship was noted with the injectate. No injury to the neurovascular structures was observed. Conclusions An accurate and safe technique with reliable anatomic landmarks was presented to perform an ACB. In addition, an increase in injected ink volume correlated to an increase in the spread of ink; thus, we postulate that 10 mL of local anesthetic may be sufficient for an adequate regional block.

There remains a critical need to develop new technologies and materials that can meet the demands of treating large bone defects. The advancement of 3-dimensional (3D) printing technologies has allowed the creation of personalized and customized bone grafts, with specific control in both macro- and micro-architecture, and desired mechanical properties. Nevertheless, the biomaterials used for the production of these bone grafts often possess poor biological properties. The incorporation of growth factors (GFs), which are the natural orchestrators of the physiological healing process, into 3D printed bone grafts, represents a promising strategy to achieve the bioactivity required to enhance bone regeneration. In this review, the possible strategies used to incorporate GFs to 3D printed constructs are presented with a specific focus on bone regeneration. In particular, the strengths and limitations of different methods, such as physical and chemical cross-linking, which are currently used to incorporate GFs to the engineered constructs are critically reviewed. Different strategies used to present one or more GFs to achieve simultaneous angiogenesis and vasculogenesis for enhanced bone regeneration are also covered in this review. In addition, the possibility of combining several manufacturing approaches to fabricate hybrid constructs, which better mimic the complexity of biological niches, is presented. Finally, the clinical relevance of these approaches and the future steps that should be taken are discussed.

Spinal fixation and fusion are surgical procedures undertaken to restore stability in the spine and restrict painful or degenerative motion. Malpositioning of pedicle screws during these procedures can result in major neurological and vascular damage. Patient-specific surgical guides offer clear benefits, reducing malposition rates by up to 25%. However, they suffer from long lead times and the manufacturing process is dependent on third-party specialists. The development of a standard set of surgical guides may eliminate the issues with the manufacturing process. To evaluate the feasibility of this option, a statistical shape model (SSM) was created and used to analyse the morphological variations of the T4–T6 vertebrae in a population of 90 specimens from the Visible Korean Human dataset (50 females and 40 males). The first three principal components, representing 39.7% of the variance within the population, were analysed. The model showed high variability in the transverse process (~ 4 mm) and spinous process (~ 4 mm) and relatively low variation (

Highlight risk factors for pseudarthrosis in long-segment spinal fusions, collect the approaches carried to address this complication. Patients with ASD and fusion of ≥ 4 levels with minimum follow-up (FU) of ≥ 2 years were included. Full-body X-rays were done preoperatively

A normal sagittal vertical axis (SVA) after spinal deformity correction can yield mechanical complications of up to 30%. Post-operative compensatory pelvic orientation can produce a normal SVA. We assess relative pelvic version (RPV), an individualised measure, for persistent post-operative compensatory measures.Adult spinal deformity (ASD) patients who were treated operatively, with a normal SVA ( ± 50 mm) at 6-week follow-up were included, who were then followed-up after 2 years. These only included patients with fusion of 4 vertebrae extending to L5 or below. Six-week subgroups were made regarding pelvis orientation, relative pelvic version (RPV: anteversion, aligned, moderate or severe retroversion) with analysis of patient-related outcome measures (PROMs), complications and spino-pelvic sagittal parameters.At 6 weeks, 140 patients met the inclusion criteria, 5 (3.6%) patients had anteversion, 59 (42.1%) were aligned, 60 (42.9%) had moderate retroversion and 16 (11.4%) patients had severe retroversion. Follow-up after 2 years demonstrated increased RPV in all groups except the severe RPV group who were more likely to develop SVA 50 mm. Complications occurred in all groups. Significant 2-year differences were observed between moderate and severe RPV for back pain and PROMs but not between other RPV groups.Adult spinal deformity patients with a normal SVA after spino-pelvic instrumentation carry a significant risk of retroversion progression post-operatively, followed by increased positive sagittal balance. Relative pelvic version (RPV) measurements when categorised into anteversion, aligned, moderate retroversion and severe retroversion at 6 weeks were predictive of PROMs at 2 years.

Purpose To evaluate the pain and functional effect of the COVID-19 pandemic on patients with ASD reflected by their response to SRS-22, ODI, and SF-36 questionnaires. Methods Patients who had stable pain and functional outcome scores over the preceding 2 years were enrolled in a local prospectively collected adult spinal deformity (ASD) database. A reanalysis of their SRS22, ODI and SF-36 data 14 days into confinement were compared to their last pre-confinement scores. Results 89 patients were included in this study (average age 60.7 years, 91% female) with an average time from last FU until confinement of 9.6 months. The ODI total score worsened by 5 points post-confinement with no difference seen in personal care, walking and social life. In contrast, the SRS-22 score showed small improvements in function/activity and satisfaction, but no significant differences for the other domains. Similarly, the SF-36 showed small improvements in physical function, physical and emotional role, vitality and PCS. Conclusion The global COVID-19 pandemic and ensuing confinement had variable overall effects on ASD patients, without the expected marked worsening. In addition, this study illustrates that the SRS-22 questionnaire is less influenced by environmental and psychological factors than the ODI supporting its objectivity and accuracy in the evaluation of the QoL of ASD patients.

Purpose: To review the literature on the value of basivertebral nerve abla-tion in the treatment of chronic low back pain. Materials and Method: A systematic review and meta-analysis of the English literature to March 2020 was undertaken. The inclusion criteria were patients with discogenic back pain of more than 3 months duration with modic type 1 or 2 change and suc-cessful disc block or discogram. Primary outcomes were VAS pain, ODI, EQ-5D and SF36 improvement. Secondary outcomes were complications. Results: 6 studies were included, all funded by the same company, but oth-erwise of low bias. All studies showed significant improvement in all scores over the first 3 months with evidence these would be maintained over the longer term. There was one reported compression fracture, but otherwise no significant adverse events. Conclusion: This study supports the conclusion that radiofrequency ablation of the basivertebral nerve is a safe and effective treatment for discogenic chronic low back pain.

Introduction The primary purpose of this review was to evaluate patient and physician preference and satisfaction for teleconsultation in orthopaedic surgery compared to traditional face-to-face consultation. In addition, we evaluated the effects of teleconsultation on patient length of visit, healthcare costs, range of motion (ROM), pain, quality of life (QOL), and ongoing management plans. Methods A systematic review of MEDLINE, Embase, Web of Science, and Cochrane Library was conducted according to PRISMA guidelines. Randomised control trials and case control studies comparing teleconsultation with traditional, face-to-face consultation in the management of orthopaedic conditions were included. The primary outcome measures were patient and physician preference and satisfaction. Secondary outcomes included patient length of visit, healthcare costs, ROM, pain, QOL, and ongoing management plans. Results A total of 13 articles meeting the eligibility criteria were included for systematic review and 8 for meta-analysis. There was no significant difference in patient satisfaction, length of visit, or time spent with the physician between the telemedicine and in-office control group. The mean difference of patient preference for telemedicine was significantly higher in the telemedicine group compared to the in-office visit group (OR 1.44, 95% CI 1.12–1.87, p = 0.005). Discussion Telemedicine was not inferior to face-to-face office visits in regard to patient and physician preference and satisfaction. Therefore, it would be an effective adjunct to face-to-face office visits, serving as a mechanism of triage and long-term continuity of care.

Objective To report the outcomes of halo femoral traction (HFT) used for 1 week between anterior release and definitive posterior fusion in adolescents with severe rigid scoliosis. Methods A retrospective single-center review of 22 consecutive patients (mean age at surgery, 14.1 years; range, 10.5–18.2 years; 17 girls) with severe, rigid scoliosis treated with anterior release, followed by HFT for 7 days prior to posterior instrumented fusion. Cobb angles were measured preoperatively, 1 week after anterior release and traction, after posterior fusion, and at a minimum 2-year follow-up. Complications were recorded. Results Mean preoperative Cobb angle was 97° (range, 80°–118°), correcting to 52° with anterior release and HFT and 31° after posterior fusion. This equated to a 68% deformity correction and was maintained at final follow-up. Three traction-related complications were experienced, including 1 case of neck pain and 2 cases of brachial plexopathy that resolved with traction weight reduction. Conclusions Three-staged deformity correction using HFT for 1 week only offers gradual correction of the spine over sufficient time to optimize deformity correction yet minimizes neurologic dysfunction.

In ballistic testing and forensic reconstruction, there is a need to use repeatable and consistent simulants. While synthetic bone is mechanically similar to human bone, it does not have the same viscoelastic properties. In high-energy impact such as ballistic impacts, bone acts as a stiff, brittle material and fails instantaneously. Therefore, a suitable simulant for use in ballistic testing should have comparable energy deposition to mammalian bones. This preliminary study aims to determine if Synbone® could be a viable proxy for Sus scrofa (domesticus) ribs in ballistic testing. Three thickness of Synbone® were embedded into 10% ballistic gelatin and shot using 5.56-mm ammunition. The models were then analysed to compare the Synbone® to a previous Sus scrofa (domesticus) rib study and focused on the number of fragments within the block, energy deposition, onset of yaw, angle of deviation, the temporary cavity as a percentage of the block and the depth to the temporary cavity centre, depth to maximum gelatin disruption and the permanent wound channel, including shear planes and wound tract diameter. There was no significant difference in the metrics that were compared between Sus scrofa (domesticus) ribs and the three thicknesses of Synbone®, except for a significant difference in the depth to maximum gelatin disruption between the 6 mm (p = 0.009) and 12 mm plate (p = 0.007) and the Sus scrofa (domesticus) ribs. This study indicates that the 5-mm Synbone® plate is a suitable proxy for Sus scrofa (domesticus) ribs for use with 5.56-mm OTM ammunition in ballistic testing.

Synthetic skin simulants are used both in wound ballistics and forensic investigations and should display similar mechanical properties to human tissue and therefore need to be validated. It is recognised that skin simulants may have a significantly different performance when different backing combinations are used; therefore, it is essential to specify and control the backing material. Roebuck 1518 synthetic chamois (RBK) backed by 20% ballistic gelatin has been validated as a suitable skin simulant; this study looks at validating the RBK simulant when backed by 10% ballistic gelatin. Two layers of RBK synthetic chamois backed by calibrated 10% ballistic gelatin were placed onto the long face of the block and secured. Steel spheres with various sectional densities were fired using a custom-made gas gun to determine the V50 of the simulants and compared with the predicted V50. The results demonstrate that for a sectional density between 2.1 and 6.6 g/cm2, the skin simulants backed by 10% gelatin are within the 35% error bounds predicted by James’ patent equation. All samples had a close fit to the regression line (R2 = 0.9738), and a Spearman rho test indicates that there is a “strong” negative correlation between sectional density and the V50 (Rs =− 0.957, p = 0.00). This validation study confirms that RBK synthetic simulant backed by 10% gelatin is a suitable skin simulant when testing non-deforming projectiles with sectional densities ranging from 2.1 to 6.6 g/cm2. A predictive trend line also indicates that the skin simulant is suitable for non-deforming projectiles with sectional densities ranging from 0.6 to 20 g/cm2 although this needs to be confirmed.

Coronal malalignment (CM) causes pain, impairment of function and cosmetic problems for adult spinal deformity (ASD) patients in addition to sagittal malalignment. Certain types of CM are at risk of insufficient re-alignment after correction. However, CM has received minimal attention in the literature compared to sagittal malalignment. The purpose was to establish reliability for our recently published classification system of CM in ASD among spine surgeons. Fifteen readers were assigned 28 cases for classification, who represented CM with reference to their full-length standing anteroposterior and lateral radiographs. The assignment was repeated 2 weeks later, then a third assignment was done with reference to additional side bending radiographs (SBRs). Intra-, inter-rater reliability and contribution of SBRs were determined. Intra-rater reliability was calculated as 0.95, 0.86 and 0.73 for main curve types, subtypes with first modifier, and subtypes with two modifiers respectively. Inter-rater reliability averaged 0.91, 0.75 and 0.52. No differences in intra-rater reliability were shown between the four expert elaborators of the classification and other readers. SBRs helped to increase the concordance rate of second modifiers or changed to appropriate grading in cases graded type A in first modifier. Adequate intra- and inter-rater reliability was shown in the Obeid-CM classification with reference to full spine anteroposterior and lateral radiographs. While side bending radiographs did not improve the classification reliability, they contributed to a better understanding in certain cases. Surgeons should consider both the sagittal and coronal planes, and this system may allow better surgical decision making for CM.

Objective To assess the efficacy and safety of surgery for dysphagia in anterior cervical idiopathic hyperostosis. Methods This retrospective study included 11 consecutive patients presenting with dysphagia and anterior cervical idiopathic hyperostosis. Computed tomography scans and dynamic swallowing fluoroscopies were performed. The site of compression and the size and position of osteophytes were measured. The clinical outcomes and complications were recorded. Results Two patients with anterior esophageal compression were found to have dysphagia caused by lower esophageal sphincter dysfunction. In the remaining 9 patients, the level of maximal compression was between C3 and C5 with the size of the osteophytes ranging from 8 to 17 mm. Intubation was challenging in 7 patients. Postoperative transient worsening of dysphagia was encountered in 3 patients. Two patients experienced severe complications including aphagia and respiratory compromise. Within 2 months of the operation, all patients reported satisfactory improvement of symptoms and a considerable gain in quality of life. No recurrence had occurred at final follow-up. Conclusions Anterior cervical hyperostosis causing dysphagia typically affects older men and results from compression between C3 and C5 from osteophytes of variable sizes. Operative intervention can provide long-lasting resolution of symptoms but is complicated by difficulty in endotracheal intubation, postoperative dysphagia, and rarely respiratory compromise. A systematic preoperative ear, nose, and throat consultation is recommended to reduce these complications.

Aims There is inconsistent evidence on whether prior spinal fusion surgery adversely impacts outcomes following total hip arthroplasty (THA). We conducted a systematic review and meta-analysis to assess the association between pre-existing spinal fusion surgery and the rate of complications following primary THA. Methods We searched MEDLINE, Embase, Web of Science, and Cochrane Library up to October 2019 for randomized controlled trials (RCTs) and observational studies comparing outcomes of dislocation, revision, or reasons for revision in patients following primary THA with or without pre-existing spinal fusion surgery. Furthermore, we compared short (two or less levels) or long (three or more levels) spinal fusions to no fusion. Summary measures of association were relative risks (RRs) (with 95% confidence intervals (CIs)). Results We identified ten articles corresponding to nine unique observational studies comprising of 1,992,366 primary THAs. No RCTs were identified. There were 32,945 cases of spinal fusion and 1,752,362 non-cases. Comparing prior spinal fusion versus no spinal fusion in primary THA, RRs (95% CI) for dislocation was 2.23 (1.81 to 2.74; seven studies), revision 2.14 (1.63 to 2.83; five studies), periprosthetic joint infection 1.71 (1.53 to 1.92; four studies), periprosthetic fracture 1.52 (1.28 to 1.81; three studies), aseptic loosening 1.76 (1.54 to 2.01; three studies), and any complications 2.82 (1.37 to 5.80; three studies) were identified. Both short and long spinal fusions, when compared with no fusion, were associated dislocation, revision, or reasons for revision. Conclusions Patients with prior spinal fusion are at risk of adverse events following primary THA. Measures that reduce the risk of these complications should be considered in this high-risk population when undergoing primary THA. These patients should also be counselled appropriately around their risks of undergoing THA. Cite this article: Bone Joint J 2020;102-B(6):664–670.

BackgroundThe prevalence of civilian 0.223 ammunition is widespread. Due to low costs and the same dimensions as a 5.56×45 mm North Atlantic Treaty Organization, this round is exceptionally popular. However, recent mass shootings have employed soft point (SP) expanding ammunition to cause grievous wounds compared with military full metal jacket (FMJ) rounds that do not rapidly expand on impact.MethodsThe aim of this given study is to compare FMJ and SP rounds to determine if there are diagnostic differences between the bullet types in the wounds inflicted to flat bones. Bos taurus scapulae were used for 25 m simulated cranial gunshot injuries. Scanning electron microscopy was employed to assess the difference in wound morphology and elemental analysis between SP and FMJ rounds.ResultsEntrance and exit wound morphology change significantly between the two different types of ammunition as seen with circumferential delamination which is indicative of FMJ rounds and is not seen with the softer SP hunting rounds. Lead staining of the entrance wound is visible on only the SP rounds.ConclusionGunshot flat bone wound morphology is distinctively different between SP and FMJ rounds. Circumferential delamination is only seen with FMJ due to the hardness of the round. Lead staining is only seen with SP rounds due to bullet composition.

BackgroundHandguns and rifles are often involved in violent deaths such as homicide and suicide. Consequently, forensic investigations are important to clarify the nature of ballistic trauma.MethodsThis study investigated the differences in entrance and exit wound morphology with Bos taurus (bovine) scapulae that have two cortical layers surrounding a central cancellous bone section which are comparable with human flat bones, with a series of experiments using six different calibres (0.22 Long Rifle, 9×19 mm North Atlantic Treaty Organization, 0.40 Smith & Wesson, 0.45 Automatic Colt Pistol, 5.56×45 mm and 7.62×51 mm). B. taurus (bovine) scapulae were used for closed range 30 cm simulated executions.ResultsThe ballistic experiments presented similarities in entrance wound morphology and exit wound bevelling with that of recognised forensic cases. As muzzle velocity increased, bevelling increased. Circumferential delamination is clearly visible with full metal jacket rounds, yielding similar bone damage morphology as human crania.ConclusionBovine scapulae seem appropriate for ballistic simulations of flat bone injuries on the macroscopic level, if the correct portion of the scapulae is deployed. More research is needed to further substantiate these interpretations.

Takamori, S, Hamlin, MJ, Kieser, DC, King, D, Hume, P, Yamazaki, T, Hachiya, M, and Olsen, PD. Senior club-level rugby union player's positional movement performance using individualized velocity thresholds and accelerometer-derived impacts in matches. J Strength Cond Res XX(X): 000-000, 2020-Game demands of professional rugby union players have been well documented; however, there is minimal game demand information using individualized velocity thresholds and collision loads, particularly for amateurs. This study investigated movement patterns of 20 male amateur rugby players during 16 senior premier division one matches using global positioning system (GPS) devices sampling at 10 Hz. Derived GPS variables included distances, velocities, sprinting, and impacts. Data files from 86 player games (≥60 minutes of play per game) were categorized into broad (forwards and backs) and specific (front row, second row, back row, half back, inside back, and outside back) positional groups for analysis. It was most likely that backs covered more distance in the high-speed running (>60% maximal velocity) zone (502 ± 157 m) compared with forwards (238 ± 147 m) (100/0/0%, chances of positive/trivial/negative differences, effect size [ES] = 1.3), performed more striding (backs 1,116 ± 240, forwards 954 ± 240 m, 96/4/0%, ES = 0.5), and sprinting (backs 121 ± 58, forwards 90 ± 65 m, 93/7/0%, ES = 0.5). However, forwards had higher collision loads (35 ± 12 arbitrary units) compared with backs (20 ± 6, 99.9/0.1/0%, ES = 1.3) with back row forwards completing the highest collision load of any playing position (40 ± 13). Our example match movement performance and impact information is valuable to coaches and support staff in preparing player profiles for similar-level rugby players to help manage their workloads.

The translation of growth factors (GFs) into clinical applications is limited by their low stability in physiological environments. Controlled GF delivery through biomaterial vehicles provides protection from proteases, targeted delivery, and longer term release profiles. However, current methods used to incorporate GFs into biomaterials still present limitations. While direct adsorption and encapsulation result in burst release, covalent incorporation provides a tailorable release profile but generally requires more complicated processes and chemical modification of the GFs. Bioaffinity methods provide long-term release profiles but fail in their specificity, resulting in GF-dependent applicability and release profiles. In the present study, we introduce tyraminated poly-vinyl-alcohol (PVA-Tyr) as a GF-delivery vehicle that can covalently incorporate native GFs through a photo-initiated cross-linking process via formation of bi-phenol bonds. Mass loss and release studies revealed that protein-loaded PVA-Tyr hydrogels had highly tailorable degradation times from 7 to 92 days, during which the covalently incorporated proteins were released in a linear fashion. The incorporation of bovine serum albumin (BSA), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), or brain-derived growth factor (BDNF) resulted in similar incorporation efficiencies and release profiles, demonstrating the low specificity and versatility of the system. Furthermore, functional studies demonstrated that VEGF, bFGF and BDNF released from the PVA-Tyr hydrogels retained the ability to increase the metabolic activity, migration, and 3D vessel formation of endothelial cells and mesenchymal stem cells. Taken together, this demonstrates that PVA-Tyr shows high potential as a highly tailorable GF delivery tool for a range of different regenerative medicine applications.

Introduction The zygapophyseal joints represent one possible cause for back pain. Therefore, many interventions are targeting the denervation of the facet joints. The aim of this study is to describe the course of the medial branch of the dorsal branch of the spinal nerve and its articular branches to the zygapophyseal joints in the segments T10–T12. Methods The medial branches in the thoracic segments T10–T12 were dissected in 20 Thiel embalmed cadavers. An Eschenbach magnifying glass (4.0× magnification) was used during dissection preserving the articular branches. The topography and the branching pattern of the medial branches was observed. Results The course of the nerves in the segments T10–T12 differed from each other because of the different osseous anatomy of each segment. The medial branch at the segment T10 crossed the tip of the transverse process in 28 of the 40 hemivertebral specimens. In the remaining cases it passed superior to the transverse process. At T11 the medial branch ran constantly through an osteofibrous canal. At the segment T12 the medial branches showed a similar course to the medial branches in the lumbar region. In many cases two articular branches, which arose from the medial branch were identified. Conclusions The results of this study show a considerable anatomic variety at the segment T10. It also demonstrates that the transverse process is an important landmark to encounter the medial branch. Furthermore, the possibility of a double innervation of the facet joints should always be considered.

BACKGROUND Sacrectomy carries significant risk of bleeding; however, specific risk factors, apart from medical comorbidities and tumor type, for this life-threatening complication remain unclear. This study describes two cases of massive bleeding, including one death during sacrectomy attributable to adherence of the internal iliac vein (IIV) and its neuroforaminal tributaries from sacral insufficiency fractures. OBSERVATIONS The authors presented two cases involving patients who received sacrectomy for a chordoma and experienced massive bleeding from the IIV due to adherence of the IIV and its neuroforaminal tributaries around sacral insufficiency fractures. They assessed their institution’s previous two decades’ experience of sacrectomies to determine risk factors for massive bleeding and performed anatomical dissection of 20 hemipelvises, which revealed the close proximity of the IIV to the sacral foraminae and the consistency of neuroforaminal tributaries arising from the foraminae. LESSONS Sacral insufficiency fractures may cause scarring that adheres to the IIV and its neuroforaminal tributaries, which risks massive bleeding during sacrectomy.

Objective: To compare the radiological and functional outcomes and complications of adult spinal deformity patients who underwent a pedicle subtraction osteotomy (PSO) below L2 but categorized according to their construct where either 2-rod or multiple-rod construct is applied.Methods: Sixty-seven patients met the inclusion criteria, and were categorized into 3 groups: 2 rods (2R), multiple rods around the PSO (MRP), multiple rods around the PSO and lumbosacral junction (MRL). Demographic data, operative parameters, spinopelvic parameters, functional outcomes, and complications were collected.Results: Health-related quality of life scores showed a better outcome at 6 months and last follow-up visits in the MRP and MRL groups which were noted on different domains of Scoliosis Research Society-22 questionnaire, 36-item Short Form Health Surve, and Oswestry Disability Index scores (p < 0.05). The 3 groups showed similar rates of rod-related complications with no significant difference (p = 0.95). And inside each group, distribution of complications between pseudarthrosis with revision and rod fracture without revision was also similar (p = 0.99).Conclusion: The use of multiple rods across the PSO did not show a better outcome when compared to single rods in terms of incidence and types of mechanical complications. However, better postoperative coronal alignment and health-related quality of life scores in the multiple rods group could be seen demonstrating an improved functional outcome.

Background The global adoption of teleconsultation has been expedited as a result of the COVID-19 pandemic. By allowing remote communication, teleconsultation may help limit the spread of the virus while maintaining the crucial patient-provider relationship. Objective The aim of this study is to evaluate the value of teleconsultation compared to in-person visits in the management of elective orthopedic and spinal procedures. Methods This was a prospective observational cohort study of 853 patients receiving orthopedic and spinal care at a private outpatient clinic in New Zealand. Patients were randomly divided into two groups: (1) patients receiving telephone consultation remotely, and (2) patients receiving in-person office consultations at the outpatient clinic. All patients received telephone consultations for 4 weeks during the mandated COVID-19 lockdown, followed by 4 weeks of telephone or in-person consultation. Patient preference, satisfaction, and duration of visit were recorded. Comparisons of patient preference between groups, visit type, sex, and location were performed using chi-square tests; similarly, satisfaction scores and visit durations were compared using a general linear model. Results We report that 91% (353/388) of patients in the telephone group preferred teleconsultation over in-person office visits during the COVID-19 lockdown (P Conclusions Patients who use telephone consultations are more likely to prefer it over traditional, in-person visits in the future. This increased preference, coupled with higher patient satisfaction scores and shorter duration of visits, suggests that teleconsultation has a role in orthopedic surgery, which may even extend beyond the COVID-19 pandemic.

BACKGROUND Periprosthetic fractures are becoming increasingly common, often leading to poor patient outcomes. The aim of this study was to identify risk factors associated with periprosthetic femoral fractures (PPFFx). METHODS Two independent reviewers conducted a systematic review of the databases MEDLINE, Embase and Cochrane Library according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, from the earliest available date to December 2017. We included all clinical articles reporting more than 100 post-operative PPFFx around total hip arthroplasty (THA). Outcomes included demographics, fracture type, risk factors and time to fracture. RESULTS A total of 12 868 PPFFx were reported across 18 eligible studies; 64% occurred following primary THA and 36% occurred after revision THA, and 66% of all fractures were in females. Vancouver B2 fractures were the most common type (39%). We found the odds of sustaining a PPFFx is significantly lower after a primary THA compared to revision THA (odds ratio 0.31, 95% confidence interval 0.24-0.40, P

Wound closure after wide, local excision of an appendicular soft‐tissue sarcoma (STS) can be challenging. This study evaluates the value of magnetic resonance imaging (MRI)‐based tumour parameters in planning wound closure. A total of 71 patients with a primary limb‐based STS, excluding vascular or osseous involvement, excluding the shoulder or hand and hip or foot were included. Axial MRI images were used to measure the circumferences and cross‐sectional areas of the limb, bone, and tumour. The tumour diameter, length, and depth at the level of maximal tumour dimension were measured to identify the tumour's relative contribution to the planning of optimal wound closure management through primary closure (PC) or reconstructive surgery (RS). Eighteen patients required planned wound RS. Wound complications occurred in 14% overall. Tumours, which were closed by PC, were of significantly greater depth, shorter radial diameter, and shorter tumour circumference relative to those closed by RS. On multivariate analysis, tumour depth was the greatest contributory factor in predicting type of wound closure. A quantitative analysis of MRI‐based tumour parameters demonstrates tumour depth as the most predictive factor in planning for the type of wound closure and may prove beneficial in providing greater insight into planned wound management of sarcoma resection.

Aim To review the published literature on the treatment of aneurysmal bone cysts (ABCs). Method A systematic review of the English literature to April 2019 for all articles, with a minimum of three patients and 2-year follow-up, reporting on the treatment of spinal ABCs. The various treatment options were compared for the rates of recurrence, complications and mortality. Results Twenty-one articles and 272 patients (mean age 16.9 years, range 3-67) were included in this review. The overall recurrence rate for ABCs following all treatments is 12.8%. This is highest in those lesions described as being treated with isolated surgiflo injection into the lesion (100%), decompression/laminectomy (42.3%), partial excision/resection (35.7%) and curettage alone (25.0%). Radiotherapy alone or in conjunction with operative intervention offers excellent cure rates. Adjuncts to operative intervention, including cryotherapy or phenol reduce the recurrence rates, whereas embolization does not. The most common complications are persistent neurological deficits, spinal deformity, and continued pain. The overall mortality rates are low (1.5%). The reoperation rates are higher in surgical than non-surgical treatments and most are performed for progressive deformity. Discussion ABCs are highly radiosensitive. However, with the unknown longer-term risk of radiotherapy, surgical treatments, ideally with complete resection, and the use of adjunctive therapies such as cryotherapy or phenol, offer the best chance of cure. SAE is a useful adjunct to reduce intraoperative bleeding, but this study suggests that it only modestly improves recurrence rates. Newer techniques including bisphosphonate and doxycycline administration offer potential benefits, but their efficacy requires further investigation.

To assess pain, health-related quality of life (HRQOL) scores and sagittal parameters of adult spinal deformity (ASD)-operated patients in the context of their analgesic consumption especially opioids (narcotics) over the first year postoperative period. In total, 372 patients from a multicenter database were stratified into 3 groups at baseline: 241 patients in the minimal group (no analgesic, or NSAIDs/narcotics weekly or less), 64 in the NSAIDs every day group and 67 in the narcotics every day group. HRQOL and back and leg pain scores were evaluated at 6 months and 1 year postoperatively. Also several sagittal alignment parameters were assessed. Significant improvements in pain and HRQOL scores were observed across all 3 groups by 1 year (P

Anastomotic leakage following colorectal surgery remains a frequent complication. We report a rare case of a fatal epidural abscess caused by a colo-epidural fistula complicating a laparoscopic proctectomy.A 62 year-old-man presented with weight loss, pelvic sepsis and neurological dysfunction four months after closing of the ileostomy following a laparoscopic proctectomy for a rectal adenocarcinoma one year ago. Cross-sectional imaging confirmed an epidural abscess caused by a chronic colorectal anastomotic leak. Systemic antibiotics and laparotomy with defunctioning pelvic loop colostomy were performed. Unfortunately, this management to control the major spinal infection failed. Epidural decompression and debridement was not possible due to his poor condition and the patient subsequently died.Colo-epidural fistula can occur as a consequence of colorectal anastomotic leakage. Prior to frank neurology symptoms and sepsis, patients may present with only a low-grade fever. Without prompt and aggressive management of colo-epidural infection, this severe complication can lead to paraplegia and death.

BACKGROUND: Mid-term clinical and radiological evaluation of a carbon-fiber cage in multilevel cervical spondylosis (MCS). Anterior cervical corpectomy and fusion (ACCF) using titanium mesh cages (TMC) has shown satisfactory outcomes, but with subsidence of up to 20%. Conventional long-fiber carbon fiber cages have shown a safe profile in discectomy/fusion (ACDF) but with minimal data in the setting of corpectomy. METHODS: Retrospective review of a single centre multi-surgeon cohort of MCS patients from 2007–2012. Follow-up period was a minimum of 3.5 years, mean 6 years. Outcomes included peri-operative, clinical [Nurick, European Myelopathy, Visual Analogue Scores (VAS), modified Japanese Orthopaedic Association (mJOA) scores and radiographic (C2C7, Cobb & ROM angles)]. RESULTS: A total of 102 consecutive patients were included. Mean length of stay was 5.5 (SD 3.5) days, blood loss 322 (SD 358) mL and operative time 98 (SD 31) min. Corpectomy levels included 72 single-level ACCF and 30 multiple ACCF. Fourteen had peri-operative complications. Three patients required early cage revisions. Mean pain scores improved from VAS neck 4.6 to 2.6 (P3 mm across the instrumented level were present in 5 patients, all of which displayed fusion of either grade 1 or 2. 7 had C2C7 kyphosis. Severe subsidence (>3 mm) was seen in 9 cases (13%). CONCLUSIONS: Mid-term outcomes of this carbon-fiber cage indicate that it is safe and durable for the treatment of MCS with a similar radiological profile to that of TMC.

Study Design Multicenter, prospective study of consecutive adult spinal deformity (ASD) patients. Objective To Validate Schwab's classification accuracy for surgical indication, and to evaluate a simplified sagittal modifier. Summary of Background Data The SRS-Schwab Radiologic Classification based on clinical impact parameters, offers 27 different sagittal classification possibilities regarding sagittal vertical alignment (SVA), pelvic tilt (PT), and pelvic incidence–lumbar lordosis (PI-LL). The high number of classification possibilities makes it complex to use. Methods Inclusion criteria were ASD patients, presenting at least 1 criteria: Cobb ≥ 20°, SVA ≥ 5 cm, thoracic kyphosis ≥ 60°, or PT ≥ 25°. A total of 1,004 patients (410 nonoperative and 594 operative) were classified regarding SVA, PT, and PI-LL (0, +, ++), and 27 possibilities were identified. Categories were formed by adding the number of + signs, considering PT, SVA, and PI-LL. Three specific categories were identified: Aligned: 0 +; Moderate deformity: 1 to 3+; and Severe deformity: 4 to 6+. A χ-square test was performed for surgical indication (operated or not) and an analysis of variance was performed to evaluate the relationship between categories and Oswestry Disability Index (ODI). Probability Results Significant differences for HRQoL scores and surgical indication were found in the 27 sagittal parameter possibilities. For nonoperative patients, 230 (56.1%) were classified as aligned, 145 (35.4%) as moderate, and 35 (8.5%) as severe. For operative patients, there were 200 (33.7%), 215 (36.2%), and 179 (30.1%) in each respective subgroup. For HRQoL scores and surgical indication, no significant differences were found within each category, but significant differences were found when comparing the subgroups. Conclusions Despite the correlation between SRS-Schwab classification and surgical indication, it is complex to use, with a total of 27 possibilities regarding sagittal modifiers. This simplification into three categories offers more readability, without losing any significant information, and could replace Schwab sagittal modifiers. In association with other parameters, they could be used for decision-making. Level of Evidence Level II.

To understand the typical presentation, risk factors, location and size, treatment, neurological recovery and survival of spontaneous spinal epidural haematomas (SSEH) in children. A systematic review of the English literature from 1 January 1960 to 1 March 2018 was performed on children aged 18 years and younger. Individual patient data were extracted and collated. Outcome measures were mode of presentation, risk factors, initial neurological findings, initial presumed diagnosis, diagnostic investigations, site and size of the SSEH, treatment, neurological recovery and survival. Thirty-one publications and 36 patients were reviewed. All age groups were affected. 83% of patients did not have a known risk factor. Back pain was reported in 61% and neurological dysfunction in 97% of patients, although not all articles defined these parameters. Initially 28% of patients were suspected of having an alternative diagnosis. All patients had an MRI and/or CT scan confirming the diagnosis. The cervical-thoracic region was most commonly affected, and the average haematoma size extended across 6.3 vertebral levels. Surgical decompression was performed in 72% of patients. Neurological function improved in 83% of patients. Two patients died as a consequence of their SSEH. SSEHs affect all paediatric age groups and typically present with neurological dysfunction and/or back pain. The initial diagnosis is incorrect in up to 28% of cases, but cross-sectional spinal imaging is diagnostic. Most SSEHs are located in the cervico-thoracic region and affect multiple spinal levels. The treatment depends on whether the patient has a bleeding disorder and their neurological status. These slides can be retrieved under Electronic Supplementary Material.

To describe the origin of the vessels supplying the anterior sub-axial cervical vertebrae (C3–C7) to further understand their potential influence on anterior bone loss after anterior cervical spinal surgery. Cadaveric dissection was performed on ten adult human necks after latex perfusion of their subclavian, common carotid and vertebral arteries. The nutrient vessels of the sub-axial cervical spine were identified and traced to their origin. The course and distribution of these vessels and their nutrient foraminae are described. In all cases the anterior nutrient vessels were derived from the thyro-cervical trunk with branches that passed over the longus coli muscles forming a leash of vessels in the pre-vertebral fascia which subsequently extended in a frond-like pattern to pass onto the anterior aspect of vertebrae. The more cranial the cervical level the fewer the number of nutrient vessels and foraminae. The distribution of the foraminae on the anterior vertebral body followed the oblique supero-medial course of the nutrient vessels. Nutrient vessels perforate the cervical vertebrae on their anterior surface. These are derived from a leash of vessels that lie within the pre-vertebral fascia overlying the longus coli muscles. The origin of these vessels is the ascending cervical artery with a variable contribution from the transverse cervical artery.

Structural failure of the spine adjacent to the level of a previous spinal fusion is commonly observed. It may be defined by the radiologic degree of adjacent deformity, often termed junctional level kyphosis, proximal junctional kyphosis or junctional level failure, or the symptomatic failure of the spine above the level of an operation, termed adjacent segment disease (ASD). ASD can be further specified according to its anatomical location of failure, which provides insight into the specific pathological cause of failure and the optimal subsequent management. This chapter describes the anatomical and pathological classification of ASD in order to help clinicians understand the cause of failure and thereby reduce its rate and offer a treatment algorithm if it occurs.

The prevalence of adult spinal deformity (ASD) is increasing worldwide, driven by changing patient demographics, as well as an increased capacity to diagnose and treat this condition. ASD carries the worst healthcare burden of all chronic conditions including arthritis, chronic lung disease, congestive heart failure, diabetes and ischaemic heart disease. Recent advances in diagnostic and treatment modalities have resulted in an increase in surgical intervention for this condition. To be successful, however, a comprehensive understanding of the functional deficits caused by ASD must be recognised by those clinicians managing such patients. This chapter provides an overview of the functional deficits caused by ASD and its treatment.

BACKGROUND Periprosthetic femoral fractures around total hip arthroplasty (THA) are increasing annually, and are a major cause for revision surgery in the New Zealand Joint Registry (NZJR). The aim of this study was to determine the timing and risk factors for periprosthetic femoral fractures in THA requiring revision surgery in the NZJR. METHODS All patients with a primary THA who sustained a periprosthetic femoral fracture requiring revision THA recorded in the NZJR were reviewed to determine age, gender, body mass index, American Society of Anesthesiologists (ASA) rating and femoral stem fixation (cemented or uncemented). Revision rates were calculated per 100 component years (cy), and risk factors determined in the first 90 days, and beyond. RESULTS Between 1999 and 2017, there were 713 revision THA for periprosthetic femoral fractures. Early revision THA was significantly associated with ASA score and body mass index ≥40. There was no gender difference (P = 0.274). The revision rate in uncemented femoral stems (1.12/100 cy) was significantly higher (p

Purpose: The global adoption of teleconsultation has been expedited as a result of the COVID-19 pandemic. By allowing remote communication, teleconsultation may help limit the spread of the virus while maintaining the crucial patient-provider relationship. The purpose of this study is to evaluate the value of teleconsultation compared to in-person visits in the management of elective orthopaedic and spinal procedures.Methods: This was a prospective observational cohort study of 853 patients receiving orthopaedic and spinal care at a private outpatient clinic in New Zealand. Patients were randomly divided into two groups: (1) patients receiving telephone consultation remotely; and (2) patients receiving in-person office consultations at the outpatient clinic. All patients received telephone consultations for four weeks during the mandated COVID-19 lockdown, followed by four weeks of telephone or in-person consultation. Patient preference, satisfaction, and duration of visit were recorded. Comparisons of patient preference between groups, visit type, sex, and location were performed using Chi-square tests; similarly, satisfaction scores and visit durations were compared using a general linear model. Results: We report that 91% of patients in the telephone group preferred teleconsultation over in-person office visits during the COVID-19 lockdown (p=0.000). A combined-group analysis shows that 55.3% of all patients preferred teleconsultation compared to 31.2% who preferred in-person office visits (p=0.000). Patients in the telephone group reported significantly higher satisfaction scores (9.95 +/- 0.04, 95% CI [9.87-10.03]) compared to patients in the in-person group (9.53 +/- 0.04, 95% CI [9.45-9.62]; p=0.000). Additionally, in-person consultations were significantly longer in duration compared to telephone consultations, with a mean visit time of 6.70 min +/-0.18, 95% CI [6.32-7.02] compared to 5.10 min +/-0.17, 95% CI [4.73-5.42], respectively (p=0.000).Conclusion: Patients who utilize telephone consultations are more likely to prefer it over traditional, in-person visits in the future. This increased preference, coupled with higher patient satisfaction scores and shorter duration of visits, suggests that teleconsultation has a role in orthopaedic surgery, which may even extend beyond the COVID-19 pandemic.

Background The aim of this study was to compare the relative performance of total hip replacement constructs and discern if there is substantial variability in performance in currently commonly used prostheses in the New Zealand Joint Registry (NZJR) using a noninferiority analysis. Methods All patients who underwent a primary total hip replacement (THR) registered in the NZJR between 1st January 1999 to June 2020 were identified. Using a noninferiority analysis, the performance of hip prostheses were compared with the best performing contemporary construct. Construct failure was estimated using the 1-Kaplan Meier survival function method to estimate net failure. The difference in failure between the contemporary benchmark and other constructs was examined. Results In total 135,432 THR were recorded comprising 1035 different THR constructs. Notably 328 constructs were used just once. Forty-eight constructs (62,251 THR) had > 500 procedures at risk at 3 years post-primary of which 28 were inferior by at least 20% relative risk of which, 10 were inferior by at least 100% relative risk. Sixteen constructs were identified with > 500 procedures at risk at 10 years with 9 inferior by at least 20%, of which one was inferior by > 100% relative risk. There were fewer constructs noninferior to the best practice benchmark when we performed analysis by gender. In females at 10 years, from 5 constructs with > 500 constructs at risk, 2 were inferior at the 20% margin. In males at 10 years, there were only 2 eligible constructs of which one was inferior at the 20% margin. Conclusions We discerned that there is substantial variability in construct performance and at most time points, just over half of constructs are inferior to the best performing construct by at least 20%. These results can facilitate informed decision-making when considering THR surgery.

Objectives in scoliosis corrective surgery include restoration of normal sagittal and coronal parameters to achieve patient satisfaction. HRQLs improvements remain limited after corrective surgery. The aim of this study was to evaluate the HRQL subclass variability specific to the sagittal and coronal correction in adult scoliosis surgery. This multi-centre prospective analysis of consecutive adult spinal deformity (ASD) patients, from five European centres, only included multilevel instrumentation for scoliosis. d-(delta) values for each parameter represented pre to post-operative changes. Parameters included demographics, baseline, 1- and 2-year. HRQL outcomes (Oswestry disability index (ODI), Scoliosis Research Society (SRS)-22 and Short Form (SF36)), sagittal correction including relative spinopelvic alignment (dRSA) and coronal correction including major Cobb (dCobb) angles. A total of 353 patients reached 1-year and 2-year follow up. All HRQL total scores significantly improved postoperatively, including ODI, SRS-22 and SF36. HRQL subclasses which displayed persistent improvements correlated to dRSA included sex-life, self-image, fatigue, vitality, social functioning. The only HRQL subclass improvement that correlated with dCobb was self-image. Adult scoliosis surgery improves overall HRQL, having a minimal effect on each variable. Importantly, greater coronal deformity correction affects only greater self-image scores, whereas with greater sagittal correction there are many greater HRQL sub-class impacts. Correction and restoration of coronal balance is one of the surgical goals in adult scoliosis but the degree to which Cobb angle is corrected, apart from self-image, does not correlate with gains in sub-classes of HRQL. These results need to be taken into account when planning surgery.

BackgroundTo assess the feasibility, safety and efficacy of a percutaneous doughnut vertebroplasty of circumferential aggressive vertebral hemangiomas (VHs).MethodsWe retrospectively reviewed our prospectively collected database of patients with VHs treated with vertebroplasty between January 2009 and January 2018. Patient demographics, clinical presentations and procedural details were recorded. All patients underwent preoperative computed tomography (CT) and magnetic resonance imaging (MRI). All vertebroplasties were performed under conscious sedation in the prone position, predominantly using biplane fluoroscopic guidance. A clinical and imaging evaluation (early CT scan and MRI) as well as a final follow-up clinical assessment was performed.ResultsTwenty-two patients with aggressive VHs who underwent circumferential vertebroplasty with cementation of the entire vertebral body and at least one posterior hemi-arch were included (six males, mean age 53 years). At 3 months follow-up, nine patients (41%) had complete, 11 (50%) had partial and two (9%) had no resolution of pain. Nine of 14 patients had a decrease in venous swelling on MRI. No complications were observed. Five patients (23%) underwent adjunctive surgery within 1 year for persistence or worsening of neurological symptoms. Clinical and radiographic improvements were maintained to final follow-up.ConclusionsDoughnut vertebroplasty offers a mini-invasive, safe and effective treatment of aggressive circumferential VHs. This technique improves pain in over 90% of patients as well as a reduction in radicular and neurological symptoms associated with a tendency to regression of the compressive epidural venous component of these lesions.

BackgroundIn the absence of cadaveric tissues, forensic simulation, trauma modelling, and cranial surgical training necessitates a surrogate for the human calvaria. This study investigates the validity ofBos taurusscapulae as a proxy for human frontal bones by comparing the laminar and cancellous bone thickness, as well as the bone mineral density (BMD) of cadaveric frontal bones and adultBos taurusscapulae.ResultsThis study aimed to validate the bovine scapulae as a valid proxy for forensic experiments, which benefit researchers and investigators who need to recreate forensic scenarios where synthetic proxies are found unsuitable due to their non-viscoelastic nature and cadaveric human models are unavailable due to ethical restrictions. Our results identified different total thicknesses of the relative bones, but non-different cortical measurements between human frontal bone and bovine scapulae. The bone mineral density is similar between both groups.ConclusionThis study has foundBos taurusscapulae to be a suitable proxy for human frontal bones as it has a similar morphology with regard to thickness and structure as well as a comparable density. However, there is a significant difference between the cancellous bone, and therefore, the overall thickness.

In ballistic testing and forensic reconstruction, there is a need to use repeatable and consistent simulants. While synthetic bone is mechanically similar to human bone, it does not have the same viscoelastic properties. In high-energy impact such as ballistic impacts, bone acts as a stiff, brittle material and fails instantaneously. Therefore, a suitable simulant for use in ballistic testing should have comparable energy deposition to mammalian bones. This preliminary study aims to determine if Synbone® could be a viable proxy for Sus scrofa (domesticus) ribs in ballistic testing.Three thickness of Synbone® were embedded into 10% ballistic gelatin and shot using 5.56-mm ammunition. The models were then analysed to compare the Synbone® to a previous Sus scrofa (domesticus) rib study and focused on the number of fragments within the block, energy deposition, onset of yaw, angle of deviation, the temporary cavity as a percentage of the block and the depth to the temporary cavity centre, depth to maximum gelatin disruption and the permanent wound channel, including shear planes and wound tract diameter.There was no significant difference in the metrics that were compared between Sus scrofa (domesticus) ribs and the three thicknesses of Synbone®, except for a significant difference in the depth to maximum gelatin disruption between the 6 mm (p = 0.009) and 12 mm plate (p = 0.007) and the Sus scrofa (domesticus) ribs.This study indicates that the 5-mm Synbone® plate is a suitable proxy for Sus scrofa (domesticus) ribs for use with 5.56-mm OTM ammunition in ballistic testing.

There is inconsistent evidence on whether prior spinal fusion surgery adversely impacts outcomes following total hip arthroplasty (THA). We conducted a systematic review and meta-analysis to assess the association between pre-existing spinal fusion surgery and the rate of complications following primary THA.We searched MEDLINE, Embase, Web of Science, and Cochrane Library up to October 2019 for randomized controlled trials (RCTs) and observational studies comparing outcomes of dislocation, revision, or reasons for revision in patients following primary THA with or without pre-existing spinal fusion surgery. Furthermore, we compared short (two or less levels) or long (three or more levels) spinal fusions to no fusion. Summary measures of association were relative risks (RRs) (with 95% confidence intervals (CIs)).We identified ten articles corresponding to nine unique observational studies comprising of 1,992,366 primary THAs. No RCTs were identified. There were 32,945 cases of spinal fusion and 1,752,362 non-cases. Comparing prior spinal fusion versus no spinal fusion in primary THA, RRs (95% CI) for dislocation was 2.23 (1.81 to 2.74; seven studies), revision 2.14 (1.63 to 2.83; five studies), periprosthetic joint infection 1.71 (1.53 to 1.92; four studies), periprosthetic fracture 1.52 (1.28 to 1.81; three studies), aseptic loosening 1.76 (1.54 to 2.01; three studies), and any complications 2.82 (1.37 to 5.80; three studies) were identified. Both short and long spinal fusions, when compared with no fusion, were associated dislocation, revision, or reasons for revision.Patients with prior spinal fusion are at risk of adverse events following primary THA. Measures that reduce the risk of these complications should be considered in this high-risk population when undergoing primary THA. These patients should also be counselled appropriately around their risks of undergoing THA. Cite this article

Background: Wiltse approaches have been shown to reduce operative blood loss and enhance recovery in lumbar spinal surgery; however, their efficacy in neuromuscular scoliosis (NMS) deformity correction has never been assessed. Thus, the purpose of this study was to compare the outcomes of deformity correction requiring pelvic fixation in NMS performed through a Wiltse approach in contrast to a standard midline approach. Methods: This is a retrospective review of 24 consecutive children with NMS undergoing deformity correction by a single surgeon in our institution. Patient demographic data, operative time, blood loss, curve correction, length of stay, and complications were recorded. Results: In 16 children, the procedure was performed through a Wiltse approach and in 8 through a midline approach. There was no significant difference in age, sex, preoperative Cobb angle, or number of levels fused. Patients who underwent a Wiltse approach had significantly less blood loss yet similar curve correction. The hospital length of stay and complication rate were not significantly different between the groups. Conclusions: A modified Wiltse approach can be safely used for NMS deformity correction. This approach achieves similar curve corrections to a traditional midline approach with less blood loss and no need for iliac screw connectors. Level of Evidence: 3.