Redesign of the American Board of Radiology Diagnostic Radiology Certifying Examination.

On April 13, 2023, the American Board of Radiology (ABR) announced plans to replace the current computer-based diagnostic radiology (DR) certifying examination with a new oral examination to be administered remotely, beginning in 2028. This article describes the planned changes and the process that led to those changes. In keeping with its commitment to continuous improvement, the ABR gathered input regarding the DR initial certification process. Respondents generally agreed that the qualifying (core) examination was satisfactory but expressed concerns regarding the computer-based certifying examination's effectiveness and impact on training. Examination redesign was conducted using input from key groups with a goal of effectively evaluating competence and incentivizing study behaviors that best prepare candidates for radiology practice. Major design elements included examination structure, breadth and depth of content, and timing. The new oral examination will focus on critical findings as well as common and important diagnoses routinely encountered in all diagnostic specialties, including radiology procedures. Candidates will first be eligible for the examination in the calendar year after residency graduation. Additional details will be finalized and announced in coming years. The ABR will continue to engage with interested parties throughout the implementation process.

Diagnostic errors in musculoskeletal oncology and possible mitigation strategies.

The objective of this paper is to explore sources of diagnostic error in musculoskeletal oncology and potential strategies for mitigating them using case examples. As musculoskeletal tumors are often obvious, the diagnostic errors in musculoskeletal oncology are frequently cognitive. In our experience, the most encountered cognitive biases in musculoskeletal oncologic imaging are as follows: (1) anchoring bias, (2) premature closure, (3) hindsight bias, (4) availability bias, and (5) alliterative bias. Anchoring bias results from failing to adjust an early impression despite receiving additional contrary information. Premature closure is the cognitive equivalent of "satisfaction of search." Hindsight bias occurs when we retrospectively overestimate the likelihood of correctly interpreting the examination prospectively. In availability bias, the radiologist judges the probability of a diagnosis based on which diagnosis is most easily recalled. Finally, alliterative bias occurs when a prior radiologist's impression overly influences the diagnostic thinking of another radiologist on a subsequent exam. In addition to cognitive biases, it is also important for radiologists to acknowledge their feelings when making a diagnosis to recognize positive and negative impact of affect on decision making. While errors decrease with radiologist experience, the lack of application of medical knowledge is often the primary source of error rather than a deficiency of knowledge, emphasizing the need to foster clinical reasoning skills and assist cognition. Possible solutions for reducing error exist at both the individual and the system level and include (1) improvement in knowledge and experience, (2) improvement in clinical reasoning and decision-making skills, and (3) improvement in assisting cognition.

Novel fusion sarcomas including targetable NTRK and ALK.

BACKGROUND: Challenging emerging entities with distinctive molecular signatures may benefit from algorithms for diagnostic work-up. METHODS: Fusion sarcomas (2020-2021, during pandemic) were diagnosed by clinicoradiology, morphology, phenotype, and next-generation sequencing (NGS). RESULTS: Six fusion sarcomas in two males and four females involved the chest-wall, neck, or extremities; ages ranged 2-73, median 18 years. Sizes ranged 5.3-25.0, median 9.1 cm. These include high grade 1) TPR-NTRK1 of proximal femur with a larger rounded soft tissue mass, previously considered osteosarcoma yet without convincing tumor matrix. A pathologic fracture necessitated emergency hemipelvectomy (NED) and 2) novel KANK1-NTRK2 sarcoma of bone and soft tissue with spindled pleomorphic to epithelioid features (AWD metastases). 3) Novel ERC1-ALK unaligned fusion, a low grade infiltrative deep soft tissue hand sarcoma with prominent-vascularity, myopericytoid/lipofibromatosis-like ovoid cells, and collagenized stroma, was successfully treated with ALK-inhibitor (Crizotinib), avoiding amputation. These NTRK and ALK tumors variably express S100 and CD34 and were negative for SOX10. 4) and 5) CIC-DUX4 round cell tumors (rapid metastases/demise), one with COVID superinfection, were previously treated as Ewing sarcoma. These demonstrated mild pleomorphism and necrosis, variable myxoid change and CD99 reactivity, and a distinctive dot-like-Golgi WT1 immunostaining pattern. 6) A chest wall/thoracic round cell sarcoma, focal CD34/ keratins/CK7, revealed nuclear-STAT6, STAT6-NAB2 by NGS, confirming malignant solitary fibrous tumor, intermediate-risk-stratification (AWD metastases). CONCLUSIONS: Recent fusion sarcomas include new KANK1-NTRK2 and ERC1-ALK, the latter successfully treated by targeted-therapy. ALK/NTRK fusion partners TPR and KANK1 suggest unusual high-grade morphology/behavior. Clinicoradiologic, morphologic, and phenotypic algorithms can prompt molecular-targeted immunostains or NGS for final classification and promising inhibitor therapy.

Scurvy: a rare case in an adult.

A 69-year-old man presented with unilateral calf pain, swelling, and erythematous rash. He was initially treated with antibiotics for suspected cellulitis. A venous duplex ultrasound, performed to exclude deep venous thrombosis, revealed multiple heterogeneous hypoechoic foci of unknown etiology throughout the calf musculature. His condition did not improve with antibiotics, instead progressing to a necrotic ulcer along the medial malleolus. Clinical suspicion of vascular insufficiency or vasculitis prompted an extensive imaging work-up. CT and MRI revealed the intramuscular abnormalities observed on previous ultrasound represented foci of intramuscular hemorrhage. Marrow signal abnormality was also noted in the proximal tibia. A punch biopsy of the skin rash ultimately demonstrated distorted hair follicles with perifollicular inflammation and hemorrhage concerning for scurvy. The diagnosis was confirmed by low vitamin C levels and dietary history. A resurgence of scurvy has occurred in the pediatric population in recent years. However, this diagnosis remains uncommon in adults, with limited reports of the potential advanced imaging findings in the current literature.

Aligning perceptions of mistreatment among incoming medical trainees.

BACKGROUND: Learner mistreatment has been a long-standing example of unprofessional behavior in medical training. Alignment of perceptions of professional behavior is a critical component of developing a defined organizational culture. Clinical vignettes addressing learner mistreatment can help to achieve this goal. Our aim was to determine whether using clinical vignettes to address learner mistreatment during onboarding can reduce variability in the perceptions of mistreatment. MATERIALS AND METHODS: External experts in the field of labor and employment relations embedded in the clinical learning environment identified six thematic areas of potential mistreatment. Corresponding clinical case vignettes were developed and presented to incoming trainees during the onboarding process, followed by facilitated discussion. Perceptions of mistreatment before and after discussion were assessed on a Likert scale, with results compared using F-test and t-test. RESULTS: There were 145 participants. Most participants reported previously witnessing or experiencing episodes of mistreatment before matriculation (84%), with the majority reporting multiple events. The most common offenders were faculty (57%), residents/fellows (49%), and nurses (33%). Only 10% of incoming trainees reported a previous incident of mistreatment. Postintervention scores demonstrated decreased variability (P < 0.05) in perceptions of mistreatment in all but one vignette (withholding learning opportunities). Two vignettes demonstrated higher perception of mistreatment after intervention (noneducational tasks and gender or racial discrimination, P < 0.05). CONCLUSIONS: Mistreatment remains a prevalent phenomenon in medical training involving a wide cross-section of healthcare providers. Trainees arrive with discordant definitions of mistreatment. Alignment of individuals' definitions can be achieved through the use of carefully crafted clinical vignettes and facilitated discussion.

Rapidly Progressive Osteoarthritis: a Review of the Clinical and Radiologic Presentation.

PURPOSE OF REVIEW: The purpose of this paper is to review the distinct clinical and radiographic features that may lead to prompt diagnosis of rapidly progressive osteoarthritis (RPOA) and thus obviate unnecessary and costly diagnostic workup. RECENT FINDINGS: RPOA is uncommon but is more frequently seen in practice because of the aging population. RPOA is a destructive arthropathy that occurs most commonly in elderly women but can also be seen in patients that have sustained trauma. The dramatic radiologic manifestations of RPOA can lead to diagnostic confusion with other arthropathies, infection, and osteonecrosis. RPOA was originally described in the hip but may also involve the shoulder. The etiology of RPOA is not well understood, but subchondral fracture probably plays a role in the development of dramatic destruction of the joint that is seen in affected patients. Early diagnosis may reduce the complexity of surgical management. RPOA is an uncommon condition that occurs most frequently in elderly woman or in patients who have sustained trauma. Prompt recognition of the clinical and radiologic features of this arthropathy can reduce unnecessary diagnostic workup and complexity of surgical intervention.

Outcomes in diabetic foot ulcer patients with isolated T2 marrow signal abnormality in the underlying bone: should the diagnosis of "osteitis" be changed to "early osteomyelitis"?

OBJECTIVE: To evaluate the variability of clinical treatment and outcomes based on reporting of diabetic foot ulcer MRI findings of adjacent marrow T2 hyperintensity with normal T1 signal. MATERIALS AND METHODS: A retrospective review was conducted of 46 MRI examinations evaluating diabetic foot ulcers that demonstrated normal T1 marrow signal, but T2 marrow hyperintensity deep to the ulcer. The cohort was divided based on MRI report impressions into three groups; "osteitis without osteomyelitis" (OW), "osteitis but cannot exclude early osteomyelitis" (OCEO) and "early osteomyelitis" (EO). Patient demographics (age, gender) and accessory MRI findings of ulcer and sinus tract depth were recorded. Initial clinical assessment and medical treatment (route and duration of antibiotics), healing versus disease progression and histology or microbiology results were recorded. RESULTS: The isolated marrow T2 signal hyperintensity was reported as OW in 12 patients, OCEO in 18, and EO in 16. No statistical difference in clinical assessment was demonstrated between the OW, OCEO, and EO groups. Pathological condition was available in 15 patients within 0-7 days (mean 2.4 days) of the MRI examination, with 14 (93%) of these positive for osteomyelitis by histopathology or positive cultures. Initial diagnosis of or progression to osteomyelitis was shown in 28 patients (61%). CONCLUSION: Treatment of suspected osteomyelitis is heavily determined by clinical factors. Patients who initially demonstrate only T2 marrow signal abnormality under a diabetic ulcer are eventually diagnosed as osteomyelitis in 61% of cases and deserve aggressive treatment as early osteomyelitis when meeting clinical parameters.

Perceptions of mistreatment among trainees vary at different stages of clinical training.

BACKGROUND: Mistreatment of trainees remains a frequently reported phenomenon in medical education. One barrier to creating an educational culture of respect and professionalism may be a lack of alignment in the perceptions of mistreatment among different learners. Through the use of clinical vignettes, our aim was to assess the perceptions of trainees toward themes of potential mistreatment at different stages of training. METHODS: Based on observations from external experts embedded in the clinical learning environment, six thematic areas of potential mistreatment were identified: verbal abuse, specialty-choice discrimination, non-educational tasks, withholding/denying learning opportunities, neglect and gender/racial insensitivity. Corresponding clinical vignettes were created and distributed to 1) medical students, 2) incoming interns, 3) residents/fellows. Perceptions of the appropriateness of the interactions depicted in the vignettes were measured on a 5-point Likert scale. Scores were categorized into neutral or appropriate (≤3) or inappropriate (i.e. mistreatment) (>3) and compared using chi-squared tests. RESULTS: Four hundred twenty seven trainees participated (182 students, 120 interns, 125 residents/fellows). Proportions of students perceiving mistreatment differed significantly from those of interns and residents/fellows in domains of verbal abuse, specialty discrimination and gender/racial insensitivity (p < 0.05). In scenarios comparing interns to residents/fellows, no significant differences were noted in perceptions of mistreatment in the domains of non-educational tasks, withholding learning and neglect. CONCLUSIONS: Perceptions of mistreatment differ at different developmental stages of medical training. After exposure to the clinical learning environment, perceptions of incoming interns did not differ from those of residents/fellows, implicating clinical rotations as a key period in indoctrinating students into the prevailing culture. More longitudinal studies are needed to confirm or better examine this phenomenon.

Subscapularis function after total shoulder arthroplasty: electromyography, ultrasound, and clinical correlation.

BACKGROUND: The literature lacks electromyographic (EMG) examination of subscapularis function in the postoperative period after total shoulder arthroplasty (TSA). The primary purpose of this study was to document EMG activity of the subscapularis after TSA and to correlate it with clinical and ultrasound findings. METHODS: The study included 30 patients who were at least 1 year (average, 2.1 years) from surgery, status post TSA approached through a standard subscapularis tenotomy. Patients returned for a physical examination, ultrasound evaluation, and EMG evaluation. Patients also completed postoperative surveys: the American Shoulder and Elbow Surgeons questionnaire, the Simple Shoulder Test, and the 12-Item Short Form Health Survey. RESULTS: The American Shoulder and Elbow Surgeons, Simple Shoulder Test, and physical 12-Item Short Form Health Survey scores improved from preoperatively to postoperatively, respectively, 45.3 to 76.8 (P = .0002), 3.9 to 9.0 (P < .0001), and 33.9 to 42.8 (P = .017). Six patients had a positive lift-off test result, and the belly-press test result was negative in all patients. Two patients had a subscapularis rupture on ultrasound. The postoperative EMG finding was normal in 15 patients; in the other 15 patients, there was evidence of chronic denervation with reinnervation changes: 30% subscapularis, 27% infraspinatus, 20% supraspinatus, 20% teres minor, and 13% rhomboids. CONCLUSIONS: This is the first study using a comparison EMG evaluation to document subscapularis function after TSA. EMG evaluation showed that active denervation of the subscapularis was not evident in any patient at least 1 year after TSA. However, in half of the patients, there was evidence of chronicdenervation and reinnervation changes across 5 muscle groups. We theorize that surgical exposure, traction, and the use of interscalene regional anesthesia may contribute to these unexpected EMG results.

Radiology fellowship with a focus on musculoskeletal imaging: current challenges and future directions.

OBJECTIVE: Many musculoskeletal fellowships are nonaccredited, leading to heterogeneity of educational experiences. There is no governing body for these nonaccredited fellowships, leaving program content and rules to the program directors' discretion. In addition, imaging fellowships in general currently face many external pressures that challenge their capacity to provide a high-quality education. Federal cuts to Medicare, diminished reimbursement to radiology departments, and pressure for increased accountability exerted by insurance companies and hospitals all place additional stress on fellowship training programs. CONCLUSION: Only those fellowships providing the highest-quality educational experience will continue to thrive.

Primary osseous tumors of the spine.

Primary osseous spinal tumors are relatively rare in comparison with metastatic disease, myeloma, and lymphoma. Despite their rarity, the interpreting radiologist must be aware of the typical imaging features to provide appropriate diagnosis for guidance of clinical management. The age of occurrence, distribution longitudinally in the spine, and distribution axially within the vertebra combined with typical imaging appearances can help indicate the correct diagnosis. This article reviews the diagnostic features of benign and malignant primary bone spinal tumors.

Radiology Training Program Lessons Learned During the COVID-19 Pandemic.

The COVID-19 pandemic had major effects on radiology training programs throughout the country. Many of the challenges were shared, with some variation depending on the size and geographic location of each program. While some initial modifications, such as platoon-type scheduling and redeployment, have been abandoned, other changes such as home workstations and the option of remote conferences have become more permanently incorporated. Remote learning tools and virtual teaching are much more frequently used, although there is emphasis by many programs on preserving in-person training. Programs stressed the importance of communication and adaptability, and getting resident and faculty input is key in optimizing the educational experience.

Bone Tumor Risk Stratification and Management System: A Consensus Guideline from the ACR Bone Reporting and Data System Committee.

The assessment and subsequent management of a potentially neoplastic bone lesion seen at diagnostic radiography is often complicated by diagnostic uncertainty and inconsistent management recommendations. Appropriate clinical management should be directed by risk of malignancy. Herein, the ACR-sponsored Bone Reporting and Data System (Bone-RADS) Committee, consisting of academic leaders in the fields of musculoskeletal oncology imaging and orthopedic oncology, presents the novel Bone-RADS scoring system to aid in risk assignment and provide risk-aligned management suggestions. When viewed in the proper clinical context, a newly identified bone lesion can be risk stratified as having very low, low, intermediate, or high risk of malignancy. Radiographic features predictive of risk are reviewed include margination, pattern of periosteal reaction, depth of endosteal erosion, pathological fracture, and extra-osseous soft tissue mass. Other radiographic features predictive of histopathology are also briefly discussed. To apply the Bone-RADS scoring system to a potentially neoplastic bone lesion, radiographic features predictive of risk are each given a point value. Point values are summed to yield a point total, which can be translated to a Bone-RADS score (1-4) with corresponding risk assignment (very low, low, intermediate, high). For each score, evidence-based and best practice consensus management suggestions are outlined. Examples of each Bone-RADS scores are presented, and a standardized diagnostic radiography report template is provided.

Use of a simulation laboratory to train radiology residents in the management of acute radiologic emergencies.

OBJECTIVE: Simulation laboratories use realistic clinical scenarios to train physicians in a controlled environment, especially in potentially life-threatening complications that require prompt management. The objective of our study was to develop a comprehensive program using the simulation laboratory to train radiology residents in the management of acute radiologic emergencies. MATERIALS AND METHODS: All radiology residents attended a dedicated simulation laboratory course lasting 3 hours, divided over two sessions. Training included basic patient management skills, management of a tension pneumothorax, massive hemorrhage, and contrast agent reactions. Participants were presented with 20 multiple-choice questions before and after the course. Pre- and posttest results were analyzed, and the McNemar test was used to compare correct responses by individual question. RESULTS: Twenty-six radiology residents attended the class. The average pre- and posttest scores and the average difference between the scores for all residents were 13.8, 17.1, and 3.3, respectively (p < 0.0001). Incorrect answers on the pretest examination that were subsequently answered correctly concerned administration of epinephrine for severe reactions, management of a tension pneumothorax, oxygen therapy, ECG placement, cardiopulmonary resuscitation technique, and where to stand during a code situation. Persistent incorrect answers concerned vasovagal reactions and emergency telephone numbers at an off-site imaging center. CONCLUSION: Simulation laboratories can be used to teach crisis management and crisis resource management for radiology residents and should be part of the education toolbox. Defined objectives lead to a comprehensive course dealing with the management of acute radiologic emergencies. Such programs can improve the role of radiologists as members of the health care team.

MR Imaging Knee Synovitis and Synovial Pathology.

Knee synovitis is a common, but nonspecific finding on MR imaging in patients with knee pain, with causes ranging from post-traumatic and osteoarthritis to inflammatory and infectious causes. Synovial thickening, joint effusion, and synovial enhancement are present across the spectrum of etiologies and do not allow differentiation between them in most instances. This article reviews synovial physiology and MR imaging of the normal synovium and synovitis, with discussion of specific pathologies and limited signs that suggest one diagnosis over another. Intravenous contrast is helpful across the spectrum of pathologies to distinguish joint fluid from synovial proliferation.

Rib hyperostosis: a benign entity with suspicious imaging features.

Rib hyperostosis has previously been described in conjunction with disorders causing excessive vertebral ossification due to osseous bridging across the costovertebral joint, such as in diffuse idiopathic skeletal hyperostosis. Hyperostosis is believed to be a reactive process due to altered forces across the affected rib as bridging osteophytes decrease mobility at the respective costovertebral joint. The imaging characteristics of rib hyperostosis can be highly suspicious for malignancy. We share 2 cases of biopsy-proven benign rib hyperostosis with imaging across multiple modalities in hopes of increasing awareness of this entity and its imaging characteristics. In the first case, a 62-year-old female without history of malignancy underwent rib biopsy after bone scintigraphy demonstrated intense radiotracer uptake along a posteromedial rib. In the second case, a 66-year-old male with history of recurrent prostate cancer underwent rib biopsy after interval development of intense radiotracer uptake on bone scintigraphy along a posteromedial rib, new compared to 6 months prior. Both cases were seen in the setting of osseous bridging at the respective costovertebral joint. Imaging findings include contiguous radiotracer uptake on bone scintigraphy confined to the rib and respective costovertebral joint, cortical bone thickening with osseous excrescence at the costovertebral joint on radiographic and cross-sectional imaging, and increased osseous edema-like change, postcontrast enhancement, and surrounding soft tissue edema on magnetic resonance imaging. By increasing awareness to these imaging features, we hope to improve diagnostic confidence and decrease unnecessary, expensive, and sometimes invasive workup for future patients.

Comparison of standard two-dimensional and three-dimensional corrected glenoid version measurements.

HYPOTHESIS: There is concern regarding the accuracy of 2-dimensional (2D) computed tomography (CT) for measuring glenoid version. Three-dimensional (3D) CT scan reconstructions can properly orient the glenoid to the plane of the scapula and have been reported to accurately measure glenoid version in cadaver models. We hypothesized that glenoid version measured by correcting 2D CT scans to the plane of the scapula by 3D reconstruction would be significantly different compared with standard 2D CT scan measurement of the glenoid in a clinical patient population. MATERIALS AND METHODS: Thirty-four patients underwent dedicated axial 2D CT scan of the shoulder with 3D reconstruction. The 2D glenoid version was measured on unmodified midglenoid axial cuts, and the 3D glenoid version measurement was corrected to be perpendicular to the plane of the scapula and then measured in the axial plane. Three observers repeated each measurement on 2 different days. RESULTS: The difference between the overall average 2D and 3D measurements was not statistically significant (P = .45). In individual scapulae, 35% of 2D measurements were 5° to 10° different and 12% were greater than 10° different from their corresponding 3D-corrected CT measurement (P < .001 to P = .045). Reproducibility of both 2D and 3D-corrected measurements was good. DISCUSSION: Although 2D and 3D corrected methods showed a high degree of both intraobserver and interobserver reliability in this series, axial 2D images without correction were 5 to 15 degrees different than their 3D-corrected counterparts in 47% of all measurements. Correcting 2D glenoid version by 3D reconstruction to the transverse plane perpendicular to the scapular body allows for an accurate assessment of glenoid version in spite of positioning differences and results in increased accuracy while maintaining high reliability. CONCLUSIONS: Owing to the variability in scapular position, the axial 2D CT scan measurement was significantly different from 3D-corrected measurement of glenoid version. Averaging the version measurements across patients did not reflect this finding.

Improved differentiation of benign osteochondromas from secondary chondrosarcomas with standardized measurement of cartilage cap at CT and MR imaging.

PURPOSE: To validate a technique for reproducible measurement of the osteochondroma cartilage cap with computed tomography (CT) and magnetic resonance (MR) imaging and to reevaluate the correlation of the thickness of the cartilage cap with pathologic findings to improve noninvasive differentiation of benign osteochondromas from secondary chondrosarcomas. MATERIALS AND METHODS: The institutional review board approved the study and waived the need for informed consent. HIPAA compliance was maintained. After validation of the measurement technique, 101 pathologically confirmed osteochondromas were retrospectively reviewed. Patient demographic data, histologic diagnosis, and chondrosarcoma grade were recorded. Two musculoskeletal radiologists used a standardized technique to independently measure the thicknesses of the cartilage caps on CT and MR images; these measurements were compared for interobserver agreement. Agreement between measurements with CT and MR imaging was also evaluated, as were the sensitivity and specificity of both modalities for differentiation of osteochondromas from chondrosarcomas. RESULTS: Evaluated were 67 benign osteochondromas (from 49 male patients and 18 female patients; mean age, 23.4 years) and 34 secondary chondrosarcomas (from 27 male patients and seven female patients; mean age, 33.2 years). On the basis of the proposed measuring technique, there was 88% interobserver measurement agreement with MR imaging (95% confidence interval [CI]: 80%, 94%) and 93% with CT (95% CI: 84%, 98%). The median difference between measurements of cap thickness at CT and MR imaging was 0 cm (25th and 75th percentiles, -3 mm and 1 mm, respectively). With 2 cm used as a cutoff for distinguishing benign osteochondromas from chondrosarcomas, the sensitivities and specificities were 100% and 98% for MR imaging and 100% and 95% for CT, respectively. CONCLUSION: The proposed measuring technique allows accurate and reproducible measurement of cartilage cap thickness with both CT and MR imaging. Cap thickness of 2 cm or greater strongly indicated secondary chondrosarcomas.

Cervical Dystonia Caused by Chronic Nonunion C2 Fracture: A Case Report.

Chronic nonunion cervical fracture leading to cervical dystonia (CD) is very rare. This study reports a 72-year-old man who presented with 9-month history of progressively worsening neck tilting, neck tightness, neck pain, headache, and difficulty with swallowing. The patient was referred to speech therapy and confirmed to have dysphagia on modified barium swallow study. A cervical spine radiograph showed a chronic C2 nonunion fracture. Subsequent cervical spine magnetic resonance imaging confirmed chronic C2 nonunion fracture with kyphotic deformity of the cervical canal with associated cord compression at C1-C2 and severe central canal stenosis. Needle electromyography revealed dystonic or spasmodic neck muscles, consistent with diagnosis of CD. Botulinum toxin injection resulted in marked clinical improvement. The patient finally underwent occipital to C4 posterior segmental fusion. No recurrence of CD had occurred 12 months after botulinum toxin injection and surgery, which supports the conclusion that chronic C2 nonunion fracture is most likely responsible for CD in this case. The authors suggest that all patients with CD receive dysphagia evaluation and more importantly cervical spine imaging to rule out chronic C2 nonunion fracture.