Intradural cervical herniated nucleus pulposus presentation and management: a case report.

Background: Intradural disc herniations (IDH) are uncommon and can be found in the cervical spine. It is commonly associated with Brown-Sequard syndrome (BSS). The case report describes cervical spine magnetic resonance imaging (MRI) findings that assists in identifying IDH pre-operatively and discusses surgical management. Case Description: This is a case report regarding a 42-year-old obese male who developed atraumatic spontaneous bilateral upper extremity numbness, right upper extremity weakness and right lower extremity weakness. MRI showed a C6-7 herniated nucleus pulposus that focally protruded through the posterior longitudinal ligament with a beak-like projection similar to what has been described in previous reports. Clinical exam revealed an incomplete spinal cord injury (SCI) most consistent with BSS. He underwent anterior cervical discectomy and fusion at the level of C6-7. Intra-operatively, a disc fragment was found to be embedded in the dura. Three months post-operatively, the patient had persistent weakness in his right lower extremity but no longer had any bilateral upper extremity weakness. Conclusions: An anterior cervical decompression and fusion was performed shortly after the patient presented, with adequate neurological recovery after 3 months. Advanced imaging with an MRI could lead to the diagnosis of an IDH and surgical intervention via the anterior approach could facilitate removal of the disc and adequate dura repair.

Bone and soft tissue tumors at the borderlands of malignancy.

This review examines findings of musculoskeletal neoplasms whose equivocal imaging and/or histopathologic features make it difficult to determine if they will show aggressive behavior. We include both intermediate tumors as defined by the World Health Organization (WHO), and a single low-grade malignancy, low-grade central osteosarcoma, which mimics a benign lesion on imaging and histology. Intermediate tumors are a broad category and are subdivided into tumors that have risk of local recurrence only, and ones that have a risk of distant limb and pulmonary metastases. Difficult intermediate musculoskeletal lesions include atypical cartilaginous tumor/grade 1 chondrosarcoma, atypical lipomatous tumor/grade 1 liposarcoma, and solitary fibrous tumor. We review diagnostic criteria, differential diagnosis, and recommendations for surveillance.

Thoracic and lumbar spine trauma classification systems fail to predict post-traumatic kyphotic deformity.

Background: Post-traumatic kyphosis of the thoracic and lumbar spine can lead to pain and decreased function. MRI has been advocated to assess ligament integrity and risk of kyphosis. Methods: All thoracic and lumbar spine MRI performed for evaluation of trauma over a 3-year period at a single institution were reviewed. Patients were included if there was an MRI showing a vertebral body fracture and follow-up radiographs. Two observers retrospectively reviewed all radiographs, CT and MRI scans, and classified injuries based on the Denis, TLICS, AO and load sharing classification systems. Change in kyphosis between injury and follow-up studies was measured. The initial radiology reports made at time of patient injury were compared to the retrospective interpretations. Results: There were 67 separate injuries in 62 patients. Kyphosis measuring ≥ 10° developed despite an intact PLC in 6/14 nonoperative cases, and 3/7 surgically treated cases; when PLC was partially injured, it developed in 6/10 cases (8 treated nonoperatively, 2 treated operatively. Thirty injuries had complete disruption of PLC by MRI, 24 treated with fusion. Kyphosis ≥ 10° developed in 3/6 treated nonoperatively, and 8/24 treated with fusion. Development of kyphosis was independent of degree of vertebral body comminution. It developed equally in patients with Grade 2 and Grade 3 Denis injuries. It developed in patients with intact PLC when multiple vertebrae were involved and/or there was compressive injury to anterior longitudinal ligament (ALL). There was high interobserver variability in assessment of severity of ligamentous injury on MRI. Conclusions: Classification systems of thoracic and lumbar spine injury and integrity of the PLC failed to predict the risk of development of post-traumatic kyphotic deformity.

A report of an intracortical chondroblastoma of the diaphysis in a skeletally mature patient.

Chondroblastomas characteristically occur in skeletally immature patients, and arise within the medullary canal of the epiphysis. We report a rare case of an intracortical chondroblastoma arising in the diaphysis, and occurring in an adult in his 3rd decade of life. Immunohistochemistry results were critical to confirmation of this rare diagnosis, with immunohistochemistry showing S100, DOG1, and H3K36me3 positivity in the neoplastic cells.

Update on MRI findings of osteomyelitis of long bones in the adult population.

OBJECTIVES: To evaluate the usefulness of new and established MRI signs of osteomyelitis in long bones in adults. METHODS: All patient records over a 9-year period with clinical or MRI suspicion for osteomyelitis were retrospectively reviewed, using strict criteria for proof of infection. Two musculoskeletal radiologists independently reviewed the MRIs of proven osteomyelitis. RESULTS: Out of 45 MRIs of confirmed osteomyelitis, 2 MRIs (4%) did not show confluent low-signal intensity on T1-weighted images, but all showed confluent high-signal intensity on T2-weighted images. Central hypoenhancing regions of marrow without abscess formation were found in 15-18/35 (43-51%) cases where gadolinium was given. We often found multiple foci of marrow replacement in the same bone. The areas of marrow involvement often had an irregular contour. Penumbra sign, marrow fat globules, and sequestra were uncommon. CONCLUSION: Multiple foci of bone marrow signal abnormalities, an irregular contour of marrow abnormality, and central marrow hypoenhancement without abscess are common signs of osteomyelitis of long bones in adults. Confluent low T1-signal intensity is not always present.

Post-arthrogram synovitis: MRI and histopathologic findings.

A 57-year-old patient developed severe, persistent pain following MR arthrography with iodinated contrast. MRI 1 week later showed synovitis which was new compared to the prior MRI. Arthroscopy showed severe synovitis. Histopathology showed synovitis characterized by lymphocytes, neutrophils, and necrosis. One out of 4 intraoperative cultures was positive, but ultimately believed to be due to contaminants. CRP normalized within 1 month. Repeat MRI 2 years later showed progressive degenerative findings, but no evidence of ongoing infection, or stigmata of previous infection. We believe this to be an unusually severe case of reactive synovitis. The purpose of the report is to add to knowledge of reactions to intra-articular contrast injection.

Solitary fibrous tumors: Clinical and imaging features from head to toe.

Solitary fibrous tumors (SFTs) are rare fibroblastic mesenchymal tumors that are usually benign with variable malignant potential. They can develop in any organ due to their spindle cell origin. The exact etiology of solitary fibrous tumors is unknown. The majority of SFTs are benign with 10-30% of them exhibiting aggressive and malignant features. The aggressiveness of this type of tumor is not associated with its histological features, which makes surgical resection the treatment of choice. We will review the clinical and radiological features and possible differential diagnoses of SFTs according to their anatomical sites following the World Health Organization 2020 classification.

The painful lateral column of the foot: from back to front.

The purpose of this article is to focus attention on the abnormalities which the radiologist may encounter in patients presenting with lateral ankle or foot pain outside of the context of acute trauma. These include anterolateral impingement, subfibular impingement, subtalar instability and tarsal sinus syndrome, tarsal coalition, sural neuromas, peroneal tendon abnormalities, calcaneocuboid instability and occult cuboid fractures, and painful accessory ossicles. The expected and unexpected findings on radiographs, CT, US, and MRI are discussed.

Destructive Arthropathy of the Femoral Head.

OBJECTIVES: Destructive arthropathy of the hip refers to noninfectious arthropathy causing extensive femoral head bone destruction. It has been described in the surgical literature using a variety of diagnostic criteria, but it remains a poorly defined entity. METHODS: Cases of destructive arthropathy diagnosed at our institution between July 1, 2015, and December 31, 2019, were identified by a free text search of the radiology database. The medical record of each case was reviewed for possible causes of femoral head destruction, clinical presentation, laboratory values, imaging studies, and pathologic diagnoses. Imaging studies and pathology specimens were retrospectively reviewed. RESULTS: Twenty femoral heads were identified in which there was 25% or greater destruction of the femoral head in the absence of infections, congenital disease, or inflammatory arthritis. Destructive arthropathy was characterized pathologically by fibromyxoid change of the marrow, aggregates of necrotic bone fragments, increased numbers of osteoclasts, increased trabecular destruction, and granuloma-like aggregates. CONCLUSIONS: The histologic findings were distinctive. We postulate that a variety of preexisting conditions set in motion a cascade of tissue factors that led to bone destruction.

A preliminary assessment of intervertebral disc health and pathoanatomy changes observed two years following anterior vertebral body tethering.

PURPOSE: Vertebral body tethering (VBT) has been reported as a safe and effective non-fusion surgical technique for the treatment of adolescent idiopathic scoliosis, but the postoperative health of the bone and soft tissues of the spine following instrumentation remains unknown. We aimed to evaluate pathoanatomy and degenerative changes of the spine in adolescent idiopathic scoliosis patients both prior to and two years following VBT. METHODS: We prospectively enrolled nine patients who underwent VBT for the treatment of progressive adolescent idiopathic scoliosis. All patients received preoperative and two-year postoperative magnetic resonance imaging of their spine; images were assessed for pathoanatomy (e.g. nucleus pulposus positioning and muscle atrophy) and degenerative changes (e.g. Schmorl nodes, endplate oedema, disc degeneration, and osteoarthritis) at each vertebral level between T1 and S1. RESULTS: Four patients (44%) exhibited a shift of the nucleus pulposus from an eccentric position at baseline towards midline at three or more levels, most of which were in the tethered region. Tethering did not affect preexisting fatty atrophy of multifidus. No patients exhibited postoperative Schmorl nodes, endplate oedema, or disc degeneration in either the tethered or untethered regions. Four patients (44%) presented with mild facet osteoarthritis in the lower lumbar spine, which did not change postoperatively. One patient developed moderate facet osteoarthritis at L5-S1. CONCLUSIONS: These preliminary data indicate that VBT may not result in significant degenerative changes in either the intervertebral discs or the posterior facets two years following instrumentation.

MRI of the Meniscus.

The menisci of the knee are accurately evaluated by MRI. Knowledge of normal anatomy, imaging parameters, imaging appearance of the normal and torn meniscus, and common anatomic variants and pitfalls are essential in obtaining the correct imaging diagnosis. There are multiple imaging signs of meniscal tear, including linear signal intensity extending to an articular surface on at least 2 images, altered meniscal shape, displaced meniscal flap, ghost meniscus, meniscal extrusion, and parameniscal cyst. After surgery, granulation tissue may mimic tear. Diagnosis is improved by comparison to preoperative images, operative note, and intra-articular contrast administration.

Improving detection of Hill-Sachs fractures on radiographs.

OBJECTIVE: To investigate factors which affect radiographic diagnosis of Hill-Sachs fractures, and find criteria which improve detection. MATERIALS AND METHODS: Retrospective search was made for the term "Hill Sachs" within MRI reports in our local PACS system, and cases with post-reduction radiographs were included in the study. Prospective diagnoses and subspecialty MSK training of the interpreting radiologist of record were recorded. Images were then retrospectively reviewed by two observers and statistical analysis was performed. RESULTS: Our retrospective study included 181 cases, of which 35% had prospective radiographic diagnosis of Hill-Sachs fracture. Retrospective review found that 73% of the radiograph series had at least 1 sign of a Hill-Sachs fracture. The internal rotation view showed a Hill-Sachs lesion in 59% of cases, but did not detect it in 14% of cases, where the lesion was instead visible on axillary, external rotation, and/or scapular Y view. Odds ratio of prospective Hill-Sachs detection on radiographs was 2.68 for musculoskeletal fellowship-trained radiologists versus non-musculoskeletal-trained radiologists. CONCLUSION: Hill-Sachs fractures are often not recognized on post-reduction radiographs. Diagnosis of Hill-Sachs lesion can be significantly increased if radiologists are aware that the internal rotation view may fail to show the injury, and if all 4 views of a shoulder series are scrutinized.

Comparison of Radiographic and Pathologic Diagnosis of Osteonecrosis of the Femoral Head.

OBJECTIVE. The purpose of this study was to assess the utility of radiography in diagnosing osteonecrosis of the femoral head with pathologic examination as the reference standard. MATERIALS AND METHODS. Radiography and pathology reports of 253 consecutive femoral head resections were reviewed. A subset of 128 cases in which the diagnosis of osteonecrosis was made or suggested radiographically or pathologically were reviewed to evaluate for factors that might influence correlation. A total of 23 patients in this subset had also undergone MRI, and those reports and images were reviewed. RESULTS. There was 93.9% agreement between radiography and pathologic examination overall (κ = 0.67). When grade 3 osteoarthritis was present, 95.0% agreement was found, but because of the large number of patients with severe osteoarthritis, the kappa value decreased to 0.51. In the subset of cases in which osteonecrosis was diagnosed or suspected, radiologic-pathologic correlation decreased as osteoarthritis grade increased, and the diagnostic uncertainty for both evaluation methods increased. One patient without osteoarthritis had osteonecrosis diagnosed in both hips at radiography and MRI, but osteonecrosis was absent at pathologic examination. CONCLUSION. Radiography depicts osteonecrosis in most patients who have osteonecrosis and subsequently undergo femoral head resection. False-positive and false-negative radiographic findings occur, however. Diagnosis is most difficult in patients with advanced osteoarthritis or subchondral fractures. The number of patients who underwent MRI was not sufficient for evaluation of the accuracy of MRI.

Limited usefulness of classic MR findings in the diagnosis of tenosynovial giant cell tumor.

OBJECTIVE: To determine the frequency with which MRI of tenosynovial giant cell tumor demonstrates hemosiderin, visible intralesional fat signal, and proximity to synovial tissue. MATERIAL AND METHODS: This is a retrospective study of 31 cases of tenosynovial giant cell tumors which had concomitant MRI. Images were examined for lesion size, morphology, origin, bone erosions, MRI signal characteristics, contrast enhancement, and blooming artifact, comparing prospective and retrospective reports. Histology was reviewed for the presence of hemosiderin and xanthoma cells. RESULTS: Eight lesions were diffuse and 23 were localized nodules. Three lesions were located in subcutaneous tissue and 4 adjacent to tendons beyond the extent of their tendon sheath. All lesions exhibited areas of low T1- and T2-weighted signal. Blooming artifact on gradient echo imaging was present in 86% of diffuse and only 27% of nodular disease. There was interobserver variability of 40% in assessing blooming. Iron was visible on H&E or iron stain in 97% of cases. Fat signal intensity was seen in only 3% of cases, although xanthoma cells were present on in 48%. The correct diagnosis was included in the prospective radiology differential diagnosis in 86% of diffuse cases and 62% of nodular cases. CONCLUSION: Blooming on GRE MRI has low sensitivity for nodular tenosynovial giant cell tumors and is not universal in diffuse tumors. There was high interobserver variability in assessment of blooming. Intralesional fat signal is not a useful sign and may occur adjacent to tendons which lack a tendon sheath and may occur in a subcutaneous location.

Problems With Open Access Publishing in Radiology.

OBJECTIVE. Open access publishing has grown exponentially and can be a means of increasing availability of scientific knowledge to readers who cannot afford to pay for access. This article discusses problems that can occur with open access and offers suggestions for ameliorating the problems facing radiology research because of poor-quality journals. CONCLUSION. Open access literature has loosed an avalanche of information into the radiology world, much of which has not been validated by careful peer review. To maintain academic integrity and serve our colleagues and patients, radiologists need to guard against shoddy science published in deceptive journals.