Total spine MRI for the preoperative evaluation of adolescent idiopathic scoliosis: part 1

Adolescent idiopathic scoliosis is a commonly encountered condition often diagnosed on screening examination. Underlying, asymptomatic neural axis abnormalities may be present at the time of diagnosis. At certain institutions, total spine MRI is obtained preoperatively to identify these abnormalities. We provide a framework for the radiologist to follow while interpreting these studies. In part 1, we discuss Arnold Chiari malformations, syringomyelia, and the tethered cord. In part 2, we focus on spinal cord tumors, dysraphisms, to include diastematomyelia, and vertebral anomalies.

Total spine MRI for the preoperative evaluation of adolescent idiopathic scoliosis: Part 2 - spinal cord tumors, dysraphisms, diastematomyelia, and vertebral anomalies

Adolescent idiopathic scoliosis is a commonly encountered condition often diagnosed on screening examination. Underlying, asymptomatic neural axis abnormalities may be present at the time of diagnosis. At certain institutions, total spine MRI is obtained preoperatively to identify these abnormalities. We provide a framework for the radiologist to follow while interpreting these studies. In part 1, we discuss Arnold Chiari malformations, syringomyelia, and the tethered cord. In part 2, we focus on spinal cord tumors, dysraphisms, to include diastematomyelia, and vertebral anomalies.

Update of pediatric bone tumors-other mesenchymal tumors of bone, hematopoietic neoplasms of bone, and WHO classification of undifferentiated small round cell sarcomas of bone

There are numerous bone tumors in the pediatric population, with imaging playing an essential role in diagnosis and management. Our understanding of certain bone tumors has rapidly evolved over the past decade with advancements in next-generation genetic sequencing techniques. This increased level of understanding has altered the nomenclature, management approach, and prognosis of certain lesions. We provide a detailed update of bone tumors that occur in the pediatric population with emphasis on the recently released nomenclature provided in the 5th edition of the World Health Organization Classification of Soft Tissue and Bone Tumours. We discuss other mesenchymal tumors of bone, hematopoietic neoplasms of bone, and WHO classification of undifferentiated small round cell sarcomas of bone. We have detailed osteogenic tumors and osteoclastic giant cell-rich tumors, as well as notochordal tumors, chondrogenic tumors, and vascular tumors of the bone in separate manuscripts.

Update of pediatric soft tissue tumors with review of conventional MRI appearance-part 1: tumor-like lesions, adipocytic tumors, fibroblastic and myofibroblastic tumors, and perivascular tumors

There are numerous soft tissue tumors and tumor-like conditions in the pediatric population. Magnetic resonance imaging is the most useful modality for imaging these lesions. Although certain soft tissue lesions exhibit magnetic resonance features characteristic of a specific diagnosis, most lesions are indeterminate, and a biopsy is necessary for diagnosis. We provide a detailed update of soft tissue tumors and tumor-like conditions that occur in the pediatric population, emphasizing each lesion's conventional magnetic resonance imaging appearance, using the recently released 5th edition of the World Health Organization Classification of Soft Tissue and Bone Tumors as a guide. In part one of this review, pediatric tumor-like lesions, adipocytic tumors, fibroblastic and myofibroblastic tumors, and perivascular tumors are discussed. In part two, vascular lesions, fibrohistiocytic tumors, muscle tumors, peripheral nerve sheath tumors, tumors of uncertain differentiation, and undifferentiated small round cell sarcomas are reviewed. Per the convention of the WHO, these lesions involve the connective, subcutaneous, and other non-parenchymatous-organ soft tissues, as well as the peripheral and autonomic nervous system.

Clinical and Anatomical Considerations for Management of a Complete Tear of the Distal Rectus Femoris Myotendinous Junction: A Rare Knee Extensor Mechanism Injury

ABSTRACT

The knee extensor mechanism is a highly complex multilayered and reinforced structure. Quadriceps muscle injuries are considered to be common, particularly among athletes; however isolated rectus femoris injuries involving the distal myotendinous junction are considered to be exceedingly rare with very few case reports published to date. Thus, the presentation and diagnosis of this injury can be elusive and treatment is nonuniform. There is limited literature published advocating both nonsurgical and surgical management. We illustrate the clinical and radiologic presentation of a traumatic, nonsport-related distal rectus femoris muscle injury treated operatively. The presentation of this injury along with anatomical and clinical considerations is portrayed in detail. This case report contributes to the sparse literature regarding this injury and delineates management considerations.

Exophytic External Occipital Protuberance Prevalence Pre- and Post-iPhone Introduction: A Retrospective Cohort

Introduction: In controversial fashion, the presence of an enlarged external occipital protuberance has been recently linked to excessive use of handheld electronic devices. We sought to determine the prevalence of this protuberance in a diverse age group of adults from two separate time periods, before and approximately 10 years after the release of the iPhone, to further characterize this theory, as if indeed valid, such a relationship could direct preventative behavior. Materials and Methods: Eighty-two cervical spine radiographs between March 7, 2007 through June 29, 2007 and 147 cervical spine radiographs between October 25, 2017 through January 1, 2018 were reviewed for the presence or absence of an exophytic external occipital protuberance. Influence of sex and age were also assessed. Results: There were 41/82 (50%) patients within the 2007 pre-iPhone group with an exophytic external occipital protuberance, ranging from 2.7-33.8 mm in length. Twenty-seven out of 82 (32.9%) had an external occipital protuberance at or above 10 mm. There were 49/147 (33.3%) patients within the 2017 post-iPhone group with an exophytic external occipital protuberance, ranging from 4.4-53.8 mm in length. Thirty-three out of 147 (22.4%) had an external occipital protuberance at or above 10 mm. When considering accessibility to the iPhone, sex, and age to the presence of an exophytic external occipital protuberance, only sex has a statistically significant association, p=0.000000033. Conclusion: We found no significant association with iPhone accessibility and an exophytic external occipital protuberance. Due to inherent limitations in the retrospective nature of the study, future research is needed to better examine the association of handheld electronic devices with exophytic external occipital protuberances.

Imaging findings of anterior hip dislocations

Anterior hip dislocations are rare orthopedic emergencies resulting from high-energy trauma and have unique imaging characteristics on radiography, computed tomography (CT), and magnetic resonance imaging (MRI). Imaging findings on CT and MRI allow for the prompt recognition and classification of anterior hip dislocations, which guides patient management and reduces complications. The purpose of this article is to review imaging findings of anterior hip dislocations, specifically focusing on CT and MRI.

Symptomatic hip plica: MR arthrographic and arthroscopic correlation

Two cases of unilateral hip pain are reported in which MR arthrography demonstrated a prominent band medial to the ligamentum teres, running in the AP direction, consistent with a hip plica. Both patients underwent hip arthroscopy with resection of the band. No labral tear or additional intra-articular pathological features was identified in either case. Both patients became asymptomatic following surgery and have remained such. The pathology report demonstrated the specimens to be a synovial band with fibroconnective tissue. This is the first MR arthrographic report of the identification and resection of a symptomatic hip plica. The symptomatic plica may represent an alternative diagnosis for mechanical hip pain.

Focal splenic lesions in type I Gaucher disease are associated with poor platelet and splenic response to macrophage-targeted enzyme replacement therapy

Focal splenic lesions (FSL) occur in Gaucher disease type I (GD1), but their clinical significance is not known. Previous studies estimated the prevalence of FSL at 4% (pediatric) to 33% (adult) of GD1 patients and reported an association with splenomegaly. We tested the hypothesis that the presence of FSL is associated with suboptimal response to macrophage-directed enzyme replacement therapy (ERT). Additionally we investigated whether FSL were associated with other phenotypic features of GD1. The splenic parenchyma was assessed by MRI performed for routine evaluation of GD1 in 239 consecutive GD1 patients with intact spleens. The prevalence of FSL was 18.4% (44/239). Following a mean of 3.5 years of ERT, platelet response was inferior among patients with FSL (80,700 ± 9,600 to 90,100 ± 7,200/mm(3) , P = 0.2) compared to patients without FSL in whom there was a robust platelet response: 108,600 ± 5,670 to 150,200 ± 6,710/mm(3), P < 0.001. Compared to patients without FSL, patients harboring FSL had worse thrombocytopenia (platelet count: 83,700 ± 8,800 vs. 112,100 ± 4,200/mm(3), P = 0.004), greater frequency of pre-ERT splenomegaly, and greater post-ERT splenomegaly (8.5 ± 0.77 vs. 4.8 ± 0.25× normal, P < 0.001). Additionally, the prevalence of osteonecrosis was higher among patients with FSL compared to patients without FSL (38 vs. 20.7%, P = 0.026). FSL appear to be a determinant of response to ERT, suggesting studies comparing relative efficacy of newly emerging therapies for GD1 should adjust for this factor. Moreover, occurrences of FSL coincide with more severe manifestations of GD1 such as avascular osteonecrosis.

Utility of flexion-extension radiographs in evaluating the degenerative cervical spine

STUDY DESIGN

Retrospective cohort of 258 consecutive patients.

OBJECTIVE

The purpose of this study is to determine the: (1) percentage of flexion-extension radiographs that revealed pathology not appreciated on neutral radiographs in the nontrauma population, and (2) frequency that these views led to a change in the management of these patients.

SUMMARY OF BACKGROUND DATA

The utility of flexion-extension radiographs in the evaluation of the spine trauma or preoperative patient is well accepted, but the role of dynamic radiographs in the degenerative population is not well defined.

METHODS

Consecutive patients presenting with axial cervical, upper extremity radicular, or myelopathic symptoms underwent upright anteroposterior, neutral lateral, and flexion-extension lateral radiographs. Patients with recent trauma, rheumatoid arthritis, prior cervical fracture, prior cervical surgery, inadequate radiographs, or congenital anomalies were excluded. Three observers reviewed all radiographs after determining the best measurement method by a priori analysis of interobserver reliability.

RESULTS

Listhesis was observed on 23 of the neutral lateral images; 6 of these were found to have changes between flexion and extension (2-4 mm). Two patients (1%) had spondylolisthesis on flexion-extension radiographs not visualized on neutral lateral radiographs. A subsequent review of these patients' charts revealed no change in management based on these findings.

CONCLUSIONS

Cervical flexion-extension radiographs are a method of assessing potential instability. In the degenerative population studied here, 1% had spondylolisthesis noted only on the flexion-extension images, and 3% had a change in spondylolisthesis. None of these, however, led to a changes in clinical management. These data, in conjunction with the extra cost and radiation exposure associated with additional views, led us to no longer regard dynamic radiographs as a useful part of the initial imaging for the patient with degenerative cervical conditions.

Design principles for developing an efficient clinical anatomy course

The exponential growth of medical knowledge presents a challenge for the medical school curriculum. Because anatomy is traditionally a long course, it is an attractive target to reduce course hours, yet designing courses that produce students with less understanding of human anatomy is not a viable option. Faced with the challenge of teaching more anatomy with less time, we set out to understand how students employ instructional media to learn anatomy inside and outside of the classroom. We developed a series of pilot programs to explore how students learn anatomy and, in particular, how they combine instructional technology with more traditional classroom and laboratory-based learning. We then integrated what we learned with principles of effective instruction to design a course that makes the most efficient use of students' in-class and out-of-class learning. Overall, we concluded that our new anatomy course needed to focus on transforming how medical students think, reason, and learn. We are currently testing the hypothesis that this novel approach will enhance the ability of students to recall and expand their base of anatomical knowledge throughout their medical school training and beyond.

Antifungal activities of pelargonic and capric acid on Microsporum gypseum

The inhibitory effects of pelargonic and capric acid on Microsporum gypseum were examined. Solid and liquid Sabouraud glucose media containing different concentrations of pelargonic and capric acid were separately prepared and inoculated with the suspension of mycelium and spores of M. gypseum and incubated at 25 degrees C for 1 month. The culture media were examined periodically for fungal growth and the minimum inhibitory concentration (MIC) of each fatty acid was determined. The MIC for capric acid was 0.02 mg ml-1 and for pelargonic acid 0.04 mg ml-1 on solid media and 0.075 mg ml-1 for capric acid and 0.05 mg ml-1 for pelargonic acid in the liquid media.

MR arthrography of the hip

Hip arthroscopy can be performed on an outpatient basis and has a shorter period of rehabilitation than is necessary after an open hip arthrotomy or reconstruction. The procedure makes possible accurate diagnosis and treatment of acetabular labral tears and loose bodies. Further advancements are necessary in optical equipment; manual and motorized equipment; and simple, reliable traction devices specific for this procedure. Refinements in patient selection and the increased availability of specific outcome data will help to define the role of hip arthroscopy in orthopedic practice.