MRI characteristics of radiographically occult femoral neck fractures in trauma patients with ipsilateral femoral shaft fractures.

PURPOSE: Ipsilateral femoral neck fractures can be seen alongside femoral shaft fractures in high-velocity trauma patients. These neck fractures are often occult on radiographs and CT, and can have a significant impact on patient outcomes if not treated promptly. Limited protocol pelvic MRI has been used to increase sensitivity for these occult fractures. Detailed characterization of these fractures on MRI is lacking. METHODS: 427 consecutive trauma patients presenting to our emergency department who had known femoral diaphyseal fractures but no ipsilateral femoral neck fracture on radiographs or CT were included in this study. These patients were scanned using a limited protocol MRI with coronal T1 and coronal STIR sequences. Presence of an ipsilateral femoral neck fracture and imaging characteristics of the fracture were obtained. RESULTS: 31 radiographically occult ipsilateral femoral neck fractures were found, representing 7% of all cases. All neck fractures were incomplete. All fractures originated along the lateral cortex of the femoral neck and extended medially towards the junction of the medial femoral neck and the lesser trochanter. 58% (18/31) were vertical in orientation. 61% (19/31) did not demonstrate any appreciate edema on STIR images. CONCLUSION: Implementation of limited protocol MRI protocol increases sensitivity for detection of femoral neck fractures in the setting of ipsilateral femoral shaft fractures not seen on radiograph or CT imaging. We describe the characteristic MR imaging features of these fractures.

The Top Three Burning Questions in Total Hip Arthroplasty.

Total hip arthroplasty (THA) for end-stage osteoarthritis is one of the most effective surgical treatments in medicine. Impressive outcomes have been well documented in the literature with patients gaining ambulation and recovery of hip joint function. Nevertheless, there are still debatable issues and controversies that the orthopedic community has not been able to provide a definitive answer for. This review is focused on the current three most debatable issues surrounding the THA procedure: (1) new cutting-edge technology, (2) spinopelvic mobility, and (3) fast-track protocols. The scope of the herein narrative review is to analyze the debatable issues surrounding the three aforementioned topics and conclude the best contemporary clinical approaches regarding each issue.

Artificial intelligence CAD tools in trauma imaging: a scoping review from the American Society of Emergency Radiology (ASER) AI/ML Expert Panel.

BACKGROUND: AI/ML CAD tools can potentially improve outcomes in the high-stakes, high-volume model of trauma radiology. No prior scoping review has been undertaken to comprehensively assess tools in this subspecialty. PURPOSE: To map the evolution and current state of trauma radiology CAD tools along key dimensions of technology readiness. METHODS: Following a search of databases, abstract screening, and full-text document review, CAD tool maturity was charted using elements of data curation, performance validation, outcomes research, explainability, user acceptance, and funding patterns. Descriptive statistics were used to illustrate key trends. RESULTS: A total of 4052 records were screened, and 233 full-text articles were selected for content analysis. Twenty-one papers described FDA-approved commercial tools, and 212 reported algorithm prototypes. Works ranged from foundational research to multi-reader multi-case trials with heterogeneous external data. Scalable convolutional neural network-based implementations increased steeply after 2016 and were used in all commercial products; however, options for explainability were narrow. Of FDA-approved tools, 9/10 performed detection tasks. Dataset sizes ranged from < 100 to > 500,000 patients, and commercialization coincided with public dataset availability. Cross-sectional torso datasets were uniformly small. Data curation methods with ground truth labeling by independent readers were uncommon. No papers assessed user acceptance, and no method included human-computer interaction. The USA and China had the highest research output and frequency of research funding. CONCLUSIONS: Trauma imaging CAD tools are likely to improve patient care but are currently in an early stage of maturity, with few FDA-approved products for a limited number of uses. The scarcity of high-quality annotated data remains a major barrier.

Is TKA femoral implant stability improved by pressure applied cement? a comparison of 2 cementing techniques.

BACKGROUND: The majority of knee endoprostheses are cemented. In an earlier study the effects of different cementing techniques on cement penetration were evaluated using a Sawbone model. In this study we used a human cadaver model to study the effect of different cementing techniques on relative motion between the implant and the femoral shaft component under dynamic loading. METHODS: Two different cementing techniques were tested in a group of 15 pairs of human fresh frozen legs. In one group a conventional cementation technique was used and, in another group, cementation was done using a pressurizing technique. Under dynamic loading that simulated real life conditions relative motion at the bone-implant interface were studied at 20 degrees and 50 degrees flexion. RESULTS: In both scenarios, the relative motion anterior was significantly increased by pressure application. Distally, it was the same with higher loads. No significant difference could be measured posteriorly at 20°. At 50° flexion, however, pressurization reduced the posterior relative motion significantly at each load level. CONCLUSION: The use of the pressurizer does not improve the overall fixation compared to an adequate manual cement application. The change depends on the loading, flexion angle and varies in its proportion in between the interface zones.

Dissociation of liner from cup in THA: does liner damage affect the risk of dissociation?

INTRODUCTION: A rare catastrophic failure of modular component Total Hip Arthroplasty is dissociation between liner and cup, which has been associated with component malposition and/or impingement and seems to be more frequently associated with the Pinnacle system. The goal of this study was to evaluate the resistance of a polyethylene liner to lever-out-forces of the Pinnacle locking mechanism and the locking mechanisms of two other current cup/liner systems using a standardized testing method (ASTM). MATERIALS AND METHODS: Five of each of the following cups were evaluated with their corresponding polyethylene liners: Pinnacle Multihole cup with and without intact anti-rotation tabs (ART's); Allofit-S-Alloclassic and Plasmafit Plus7 cups. The ASTM test set-up was used to evaluate the lever-out force resulting in liner dissociation for each construct. RESULTS: The Pinnacle construct with intact ARTs required the greatest force (F) to achieve dissociation (263.2 ± 79.2 N) followed by the Plasmafit Plus7 (185.8 ± 36.9 N) and the Allofit-S (101.4 ± 35.3 N) constructs, respectively. However, after removal of the ARTs, the Pinnacle system required the least force to achieve dissociation (75.1 ± 22.2 N) (p < 0.001). CONCLUSIONS: The intact Pinnacle system appeared the most stable in lever-out tests when compared to the other systems. However, after removal of the ARTs, the Pinnacle system required the least force for dissociation, consistent with locking mechanism failure, and suggesting that the ARTs are a critical component of the locking mechanism. Our findings are consistent with the clinical experience of dissociated Pinnacle constructs displaying damaged or missing ARTs, and that damage to these may increase risk of liner dissociation.

Transversal Malalignment and Proximal Involvement Play a Relevant Role in Unilateral Cerebral Palsy Regardless the Subtype.

Classification of gait disorders in cerebral palsy (CP) remains challenging. The Winters, Gage, and Hicks (WGH) is a commonly used classification system for unilateral CP regarding the gait patterns (lower limb kinematics) solely in the sagittal plane. Due to the high number of unclassified patients, this classification system might fail to depict all gait disorders accurately. As the information on trunk/pelvic movements, frontal and transverse planes, and kinetics are disregarded in WGH, 3D instrumented gait analysis (IGA) for further characterization is necessary. The objective of this study was a detailed analysis of patients with unilateral CP using IGA taking all planes/degrees of freedom into account including pelvic and trunk movements. A total of 89 individuals with unilateral CP matched the inclusion criteria and were classified by WGH. Subtype-specific differences were analyzed. The most remarkable findings, in addition to the established WGH subtype-specific deviations, were pelvic obliquity and pelvic retraction in all WGH types. Furthermore, the unclassified individuals showed altered hip rotation moments and pelvic retraction almost throughout the whole gait cycle. Transversal malalignment and proximal involvement are relevant in all individuals with unilateral CP. Further studies should focus on WGH type-specific rotational malalignment assessment (static vs. dynamic, femoral vs. tibial) including therapeutic effects and potential subtype-specific compensation mechanisms and/or tertiary deviations of the sound limb.

Outcome Prognostic Factors in MRI during Spica Cast Therapy Treating Developmental Hip Dysplasia with Midterm Follow-Up.

Closed reduction followed by spica casting is a conservative treatment for developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) can verify proper closed reduction of the dysplastic hip. Our aim was to find prognostic factors in the first MRI to predict the possible outcome of the initial treatment success by means of ultrasound monitoring according to Graf and the further development of the hip dysplasia or risk of recurrence in the radiological follow-up examinations. A total of 48 patients (96 hips) with DDH on at least one side, and who were treated with closed reduction and spica cast were included in this retrospective cohort study. Treatment began at a mean age of 9.9 weeks. The children were followed for 47.4 months on average. We performed closed reduction and spica casting under general balanced anaesthesia. This was directly followed by MRI to control the position/reduction of the femoral head without anaesthesia. The following parameters were measured in the MRI: hip abduction angle, coronal, anterior and posterior bony axial acetabular angles and pelvic width. A Graf alpha angle of at least 60° was considered successful. In the radiological follow-up controls, we evaluated for residual dysplasia or recurrence. In our cohort, we only found the abduction angle to be an influencing factor for improvement of the DDH. No other prognostic factors in MRI measurements, such as gender, age at time of the first spica cast, or treatment involving overhead extension were found to be predictive of mid-term outcomes. This may, however, be due to the relatively small number of treatment failures.

Interventional Therapies for Osteoarthritis: An Update.

Osteoarthritis (OA) is one of the most common diseases worldwide and is expected to increase in incidence as the age of the general population rises. Both oral medications, such as NSAIDs, and surgical treatments used for OA management have limitations. Demand is rising for minimally invasive techniques such as intraarticular injections and percutaneous interventions for use in place of or in conjunction with oral medications and surgical therapies, and the past 2 decades have seen a rapid expanse in both pharmacologic and nonpharmacologic minimally invasive OA treatments. Image guidance with fluoroscopy, CT, or ultrasound is often used in conjunction with these procedures to achieve precise treatment localization to achieve maximal therapeutic effect. The choice of modality used for image guidance is often influenced by clinician experience, patient characteristics, and equipment availability. This article reviews the mechanisms of action, contraindications, complications, and efficacy of conventional and developing minimally invasive OA treatments. The minimally invasive treatment options described in this Review include therapeutic injections such as antiinflammatory agents, viscosupplements, and biologics, as well as nonpharmacologic treatments of subchondroplasty, nerve ablation, genicular artery embolization, intraarticular pulsed radiofrequency therapy, and MRI-guided focused ultrasound therapy.

GMFCS Level-Specific Differences in Kinematics and Joint Moments of the Involved Side in Unilateral Cerebral Palsy.

A variety of gait pathologies is seen in cerebral palsy. Movement patterns between different levels of functional impairment may differ. The objective of this work was the evaluation of Gross Motor Function Classification System (GMFCS) level-specific movement disorders. A total of 89 individuals with unilateral cerebral palsy and no history of prior treatment were included and classified according to their functional impairment. GMFCS level-specific differences, kinematics and joint moments, exclusively of the involved side, were analyzed for all planes for all lower limb joints, including pelvic and trunk movements. GMFCS level I and level II individuals most relevantly showed equinus/reduced dorsiflexion moments, knee flexion/reduced knee extension moments, reduced hip extension moments with pronounced flexion, internal hip rotation and reduced hip abduction. Anterior pelvic tilt, obliquity and retraction were found. Individuals with GMFCS level II were characterized by an additional pronounced reduction in all extensor moments, pronounced rotational malalignment and reduced hip abduction. The most striking characteristics of GMFCS level II were excessive anterior pelvic/trunk tilt and excessive trunk obliquity. Pronounced reduction in extensor moments and excessive trunk lean are distinguishing features of GMFCS level II. These patients would benefit particularly from surgical treatment restoring pelvic symmetry and improving hip abductor leverage. Future studies exploring GMFCS level-specific compensation of the sound limb and GMFCS level-specific malalignment are of interest.

Femoral Head and Liner Exchange in Patients with Atraumatic Dislocation. Results of a Retrospective Study with 6 Years Follow-Up.

Background and Objectives: Femoral head and liner exchange is an established treatment for polyethylene wear but has had a more limited role in the treatment of other conditions including dislocation, because of concerns about an increased postoperative dislocation rate. Some authors have considered dislocation associated with polyethylene wear to be a contraindication for this procedure. Materials and Methods: Our retrospective review evaluated the outcome of head and liner exchange in a small consecutively operated heterogeneous cohort of 20 patients who presented with dislocation unrelated to trauma, component malposition or component loosening. Of this group, 12 had prior primary total hip arthroplasty, and 8 had prior revision total hip arthroplasty, and included 4 patients with prior revision for dislocation. Mean follow-up was 6 ± 3.5 years (range 1-145 months). Results: Kaplan-Meier analysis revealed a revision-free implant survival from any cause of 80% (confidence interval 95%:64.3-99.6%) at 5 years after head and liner exchange (index surgery). At final follow-up, 83.3% of patients (n = 10) with prior primary total hip arthroplasty and 62.5% of patients (n = 5) with prior revision total hip arthroplasty, had not required subsequent revision for any cause. None (0%) of the primary total hip arthroplasty group and 3 (38%) of the revision arthroplasty group had required revision for further dislocation. Of the eight revision arthroplasty patients, four had a prior revision for dislocation and three of these four patients required further revision for dislocation after index surgery. The fourth patient had no dislocation after index surgery. One additional patient who had prior revision surgery for femoral component fracture suffered dislocation after index surgery, but was successfully treated with closed reduction. Conclusions: In our study population, femoral head and liner exchange was an effective treatment option for patients with prior primary total hip arthroplasty and also for a highly select group of revision total arthroplasty patients with no prior history of dislocation. Femoral head and liner exchange does not appear to be a viable treatment option for patients who have had revision total arthroplasty after prior dislocations.

Primary Stability in Hip Revision Arthroplasty: Comparison of the Stability of Cementless Fixed Augments on a Modular Acetabular Cage System with and without Cranial Straps.

The goal of this study is to evaluate the primary stability of a cementless augment-and-modular-cage system with and without the addition of cranial straps in a standardized in vitro setting. As the surrogate parameter for the evaluation of primary stability, the measurement of relative motion between the implant components themselves and the bone will be used. Acetabular revision components with a trabecular titanium augment in combination with a large fourth-generation composite left hemipelvis were assembled. These constructs were divided into two groups with (S) and without cranial straps (nS). A total of 1000 cycles was applied at each of three load levels. Relative movements (RM) between the components were measured. Load levels display a significant effect on the amount of RM at all interfaces except between shell/augment. The group assignment appears to have an effect on RM due to significantly differing means at all interfaces. Between bone/shell RM increased as load increased. NS displayed significantly more RM than S. Between shell/augment RM remained constant as load increased. Between shell/cup S showed more RM than nS while both groups' RM increased with load. We conclude a significant increase of primary stability between the shell and the bone through the addition of cranial straps. Relative motion between components (shell/cup) increases through the addition of cranial straps. A clinical impact of this finding is uncertain and requires further investigation. Finally, the cementless fixation of the augment against the rim-portion of the shell appears stable and compares favorably to prior investigation of different fixation techniques.

Is Negative Pressure Wound Therapy with Instillation Suitable for the Treatment of Acute Periprosthetic Hip Joint Infection?

BACKGROUND: Periprosthetic joint infection (PJI) can be devastating for the patient and demanding for the surgeon. In acute PJI, attempts are made to retain the prosthesis by debridement of the infected tissue, targeted antibiotic therapy and an exchange of modular components with implant retention (DAIR). There has been sparse research with adjunctive negative pressure wound treatment with wound irrigation (NPWTI) on the treatment outcome. QUESTIONS/PURPOSES: The goal was to assess the efficacy of our protocol of DAIR with adjunctive NPWTI in acute PJI and to reduce the need for later additional DAIR and Irrigation and Debridement (I and D). PATIENTS AND METHODS: Our cohort of 30 patients (31 hips) with acute PJI was divided into two groups based on symptom presentation up to 6 weeks or >6 weeks from prior (index) surgery (acute early or acute late groups, respectively). All received DAIR with an exchange of modular components and NPWTI with polyhexanide instillation, with the goal of bacterial elimination and biofilm elimination. Postoperatively, the patients were followed up clinically and radiographically for a mean of 4.3 years. RESULTS: Of the 31 PJI hips, 19 were early acute and 12 were late acute. In total, 21 hips had no evidence of residual infection, 10 required further surgical revision: 1 due to dislocation and 9 due to infection. Of these nine, seven had a removal of all the components and two were treated with irrigation and debridement (I and D), with the demise of one patient from pneumonia shortly after the procedure. The Kaplan-Meier 60-month revision free implant survival from infection was 73.2% (CI: 58.9-91.0%) and at the final follow up, the mean Harris Hip Score (HHS) was 81.1 ± 11.8 and the mean WOMAC score was 33.3 ± 20.1. CONCLUSIONS: Our results are in line with those reported in prior studies. However, the utility of our protocol is inconclusive and needs further evaluation based on our small cohort and the lack of a control group. LEVEL OF EVIDENCE: IV.

Lemierre's Syndrome Due to the Zoonotic Anaerobe Bacteroides pyogenes: Case Report and Literature Review.

Although Fusobacterium necrophorum is well described as an emerging pathogen of acute mastoiditis in young children, infection with other anaerobes can lead to similar severe sequelae including intracranial and extracranial suppurative thrombophlebitis and sepsis. We describe a patient whose unremarkable exposure history assumed increased significance upon obtaining the results of 16S next generation sequencing from a surgical specimen. The novel pathogen Bacteroides pyogenes is reviewed herein.

Application of the reversed LISS-DF technique in an elderly patient to salvage infection-related failure of trochanteric fracture fixation.

Failure of cephalomedullary fixation in geriatric trochanteric fractures is a potential complication. Attempts have been made to optimize the implant fixation (e. g. cement augmentation) and several factors (e. g. malreduction, tip apex distance) have been identified as risk factors for failure. Nevertheless, if intramedullary fixation fails, it is often associated with bone defects in mostly preexisting poor bone-stock. Accordingly, conversion to total hip arthroplasty (THA) is recommended by some authors as the only valid treatment option. However, in specific situations (e. g. implant associated infection) conversion to THA might be less reasonable than an attempt to re-osteosynthesis. This article reports on the successful use of a reversed contralateral LISS-DF (LISS for the distal femur, DePuy Synthes, Zuchwil, Switzerland) application after failed cephalomedullary fixation and failed re-osteosynthesis using a blade plate in a trochanteric fracture in an elderly patient with additional implant associated infection.

Imaging of pediatric cervical spine trauma.

While pediatric cervical spine injuries (CSI) are rare, they are associated with high morbidity and mortality and sometimes require expeditious surgical management. In this article, we aim to improve the diagnostic accuracy of pediatric CSI by reviewing normal pediatric cervical anatomy, typical pediatric CSI patterns, and common mimics of pediatric CSI. A literature review was conducted on pediatric CSI, its epidemiology, and the various imaging manifestations and mimics. The most common pediatric CSI occur in the upper cervical spine owing to the higher fulcrum and larger head at a young age, namely prior to age 9 years, while lower CSI occur more frequently in patients older than 9 years. While various craniocervical measurements may be utilized to identify craniocervical disruption, soft tissue injuries may be the only manifestation, thus making pediatric CSI difficult to diagnose on initial imaging. In the acute setting, CT cervical spine is an appropriate initial imaging modality for pediatric CSI evaluation. MRI serves as an additional tool to exclude or identify injuries when initial findings are equivocal. It is essential to recognize the unique anatomy and biomechanics of the pediatric spine and thus discern common pediatric CSI patterns and their mimics.

Accuracy of craniocervical measurements on CT for identifying partial or complete craniocervical ligament injuries in pediatric patients.

PURPOSE: To assess the accuracy of craniocervical measurements for identifying craniocervical injuries and the frequency of subjective findings of craniocervical injuries on CT in pediatric patients. METHODS: Case-controlled retrospective review of patients ≤ 16 years old with craniocervical junction injuries. Receiver operator curves were created for common craniocervical measurements on CT comparing patients with complete and partial craniocervical injuries to uninjured cohort. Frequency of subjective CT findings of craniocervical injury was assessed in the injured cohort. RESULTS: For complete disruption injuries (CD) (n = 27), C1-C2 distance (AUC = 0.90, 95%CI = 0.83-0.97), atlanto-occipital distance (AUC = 0.95-0.98, 95%CI = 0.90-1.00), and basion-dens distance (AUC = 0.90, 95%CI = 0.82-0.98) had excellent accuracy diagnosing injury. Powers ratio (AUC = 0.85, 95%CI = 0.76-0.94) had good, basion-posterior axial line (AUC = 0.74, 95%CI = 0.61-0.86) fair, and atlanto-dental distance (AUC = 0.69, 95%CI = 0.57-0.82) poor accuracy. For partial disruption injuries (PD) (n = 21), basion-dens distance (AUC = 0.75, 95%CI = 0.62-0.88) had fair accuracy diagnosing injury. Powers ratio (AUC = 0.63, 95%CI = 0.47-0.79), C1-C2 distance (AUC = 0.60, 95%CI = 0.45-0.75), atlanto-dental distance (AUC = 0.55, 95%CI = 0.39 = 0.71), atlanto-occipital distance (AUC = 0.63-0.65, 95%CI = 0.47-0.81), and basion-posterior axial line (AUC = 0.60, 95%CI = 0.44-0.76) all had poor accuracy. Eighty-one percent (n = 22) of CD and 38% (n = 8) of PD patients had non-concentric atlanto-occipital joints. One hundred percent of CD patients had ≥ 1 soft tissue finding and eighty-one percent (n = 22) had ≥ 2 findings. Seventy-three percent (n = 16) of PD patients had ≥ 1 soft tissue finding. Eighty-six percent (n = 18) of PD patients had non-concentric atlanto-occipital joints and/or soft tissue findings. CONCLUSION: Craniocervical measurements have poor accuracy for identifying craniocervical injuries in pediatric patients with incomplete craniocervical ligament disruption. Subjective findings of craniocervical injury are frequently present on CT in pediatric patients and can help increase sensitivity for identifying injury.

Sialendoscopy and Sjogren's Disease: A Systematic Review.

OBJECTIVES/HYPOTHESIS: This study is a systematic review of the literature which seeks to estimate the expected treatment outcomes of a patient with Sjogren's syndrome (SS) undergoing therapeutic sialendoscopy. STUDY DESIGN: Systematic Review. METHODS: PubMed, Scopus, and Cochrane library databases were used to search for studies published as of August 2020 regarding the treatment outcomes of SS with sialendoscopy. The key search terms included "Sjogren's syndrome" and "sialendoscopy." Only studies in the English language involving more than one human patient were included. PRISMA guidelines were followed in study inclusion and data extraction. The primary outcome assessed was improvement in patient symptoms. RESULTS: Six studies met criteria and were analyzed in this review, including 125 patients undergoing sialendoscopy of parotid and/or submandibular glands as well as 25 controls. Of these patients, 90% were female with an age range of 18 to 79 years. There was significant diversity in outcome reporting tools. The outcomes of symptom improvement were pooled qualitatively based on improvement noted in each study. Outcomes were defined as partial improvement if the measured outcomes improved and complete improvement if measured outcomes resolved entirely. Despite the limited number of studies on this topic, this meta-analysis suggests that a similar study of therapeutic sialendoscopy could expect to provide at least temporary improvement of symptoms 90% to 99% of the time. CONCLUSIONS: This review provides support for the application of sialendoscopy in the treatment of SS salivary disease. Larger studies with consistent outcome reporting tools and control groups are needed to validate these results and provide a consistent therapy protocol. Laryngoscope, 131:1474-1481, 2021.