Radiologists' Diagnostic Performance in Differentiation of Rickets and Classic Metaphyseal Lesions on Radiographs: A Multicenter Study.

BACKGROUND. Despite evidence supporting the specificity of classic metaphyseal lesions (CML) for the diagnosis of child abuse, some medicolegal practitioners claim that CML result from rickets rather than trauma. OBJECTIVE. The purpose of this study was to evaluate radiologists' diagnostic performance in differentiating rickets and CML on radiographs. METHODS. This retrospective seven-center study included children younger than 2 years who underwent knee radiography from January 2007 to December 2018 and who had either rickets (25-hydroxyvitamin D level < 20 ng/mL and abnormal knee radiographs) or knee CML and a diagnosis of child abuse from a child abuse pediatrician. Additional injuries were identified through medical record review. Radiographs were cropped and zoomed to present similar depictions of the knee. Eight radiologists independently interpreted radiographs for diagnoses of rickets or CML, rated confidence levels, and recorded associated radiographic signs. RESULTS. Seventy children (27 girls, 43 boys) had rickets; 77 children (37 girls, 40 boys) had CML. Children with CML were younger than those with rickets (mean, 3.7 vs 14.2 months, p < .001; 89.6% vs 5.7% younger than 6 months; 3.9% vs 65.7% older than 1 year). All children with CML had injuries in addition to the knee CML identified at physical examination or other imaging examinations. Radiologists had almost perfect agreement for moderate- or high-confidence interpretations of rickets (κ = 0.92) and CML (κ = 0.89). Across radiologists, estimated sensitivity, specificity, and accuracy for CML for moderate- or high-confidence interpretations were 95.1%, 97.0%, and 96.0%. Accuracy was not significantly different between pediatric and nonpediatric radiologists (p = .20) or between less experienced and more experienced radiologists (p = .57). Loss of metaphyseal zone of provisional calcification, cupping, fraying, and physeal widening were more common in rickets than CML, being detected in less than 4% of children with CML. Corner fracture, bucket-handle fracture, subphyseal lucency, deformed corner, metaphyseal irregularity, and subperiosteal new bone formation were more common in CML than rickets, being detected in less than 4% of children with rickets. CONCLUSION. Radiologists had high interobserver agreement and high diagnostic performance for differentiating rickets and CML. Recognition that CML mostly occur in children younger than 6 months and are unusual in children older than 1 year may assist interpretation. CLINICAL IMPACT. Rickets and CML have distinct radiographic signs, and radiologists can reliably differentiate these two entities.

Shoulder Position During Magnetic Resonance Arthrogram Significantly Affects Capsular Measurements.

PURPOSE: To determine whether change in shoulder position between internal rotation (IR) and external rotation (ER) during magnetic resonance arthrography (MRA) affects previously defined capsular measurements and to determine the utility of rotation in the diagnosis of instability. METHODS: A retrospective study was conducted of patients who received a shoulder MRA with humeral IR and ER views. Patients with an arthroscopically confirmed diagnosis of instability and those with clinically stable shoulders, no history of instability, and no MRA findings of instability were identified and compared. Humeral rotation, glenoid retroversion, humeral head subluxation, capsular length, and capsular area using axial sequences of IR and ER views were recorded. Analysis compared IR, ER, and Δ capsular measurements between groups using independent t tests and univariate and multivariate regression. RESULTS: Thirty-one subjects who were diagnosed with instability were included, along with 28 control subjects. Capsular length, capsular area, and humeral subluxations were significantly greater with ER compared with IR views (P < .001, P < .001, P < .001). Patients with instability displayed greater ER capsular length (P = .0006) and ER capsular area (P = .005) relative to controls. Multivariate logistic regression identified age, weight, sex, ER capsular length, and retroversion to be significant predictors of instability. ER capsular length independently predicts instability with 86% sensitivity and 84% specificity. Interobserver reliability using the intraclass correlation coefficient was rated good or excellent on all measurements. CONCLUSION: Variance in humeral rotation during shoulder MRA significantly affects capsular measurements. Rotational views increase the utility of capsular measurements when assessing for instability, particularly capsular length and capsular area. The implementation of ER positioning enhances the ability to examine capsular changes of the shoulder joint and can assist in the diagnosis of instability. LEVEL OF EVIDENCE: III, retrospective comparative study.

MRI diagnosis of rubber band constriction syndrome.

Rubber band syndrome is caused by constriction of the wrist from elastic bracelets worn for decorative purposes. Overtime, the fixed or elastic band burrows into the skin and becomes invisible. We present the case of a 2.5-year-old female child presenting to our institution with signs of circumferential swelling and inflammatory changes about the right wrist. MRI of the wrist demonstrated a subcutaneous circular foreign body, which was confirmed at surgery to be a rubber band. Although this disease entity is rare, radiologists can be instrumental in suggesting this diagnosis based on the location involved, ie, wrist, and the imaging findings.

Quadriceps Recovery After Anterior Cruciate Ligament Reconstruction With Quadriceps Tendon Versus Patellar Tendon Autografts.

BACKGROUND: Quadriceps tendon (QT) autografts are being increasingly used for anterior cruciate ligament reconstruction (ACLR). A paucity of studies exist that compare QT autografts with alternative graft options. Additionally, concerns exist regarding quadriceps recovery after graft harvest insult to the quadriceps muscle-tendon unit. PURPOSE/HYPOTHESIS: The purpose of this study was to compare quadriceps recovery and functional outcomes in patients with QT versus bone-patellar tendon-bone (BPTB) autografts. The hypothesis was that those with QT autografts would demonstrate superior outcomes. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Active patients with a history of primary, unilateral ACLR with soft tissue QT or BPTB autografts participated. Quadriceps recovery was quantified using variables of strength, muscle size, and activation. Knee extensor isometric and isokinetic strength was measured bilaterally with an isokinetic dynamometer and normalized to body weight. Quadriceps activation was measured with the superimposed burst technique. The maximal cross-sectional area of each quadriceps muscle was measured bilaterally using magnetic resonance imaging. Assessors of muscle size were blinded to the graft type and side of ACLR. Functional tests included hop tests and step length symmetry during walking, measured via spatiotemporal gait analysis. Self-reported function was determined with the International Knee Documentation Committee (IKDC) questionnaire. Neuromuscular and functional outcomes were expressed as limb symmetry indices (LSIs: [surgical limb/nonsurgical limb]*100%). Wilcoxon rank-sum tests were used to compare the LSIs and IKDC scores between groups. RESULTS: There were 30 study participants (19 male, 11 female; median age, 22 years [range, 14-41 years]; median time since surgery, 8 months [range, 6-23 months]), with 15 patients in each group. There were no significant between-group differences in demographic variables or outcomes. LSIs were not significantly different between the QT versus BPTB group, respectively: knee extensor isokinetic strength at 60 deg/s (median, 70 [range, 41-120] vs 68 [range, 37-83]; P = .285), activation (median, 95 [range, 85-111] vs 92 [range, 82-105]; P = .148), cross-sectional area of the vastus medialis (median, 79 [range, 62-104] vs 77 [range, 62-95]; P = .425), single-leg hop test (median, 88 [range, 35-114] vs 77 [range, 49-100]; P = .156), and step length symmetry (median, 99 [range, 93-104] vs 98 [range, 92-103]; P = .653). The median IKDC scores between the QT and BPTB groups were also not significantly different: 82 (range, 67-94) versus 83 (range, 54-94); respectively (P = .683). CONCLUSION: Patients with QT autografts demonstrated similar short-term quadriceps recovery and postsurgical outcomes compared with patients with BPTB autografts.

Voriconazole-associated periostitis presenting as hypertrophic osteoarthropathy following lung transplantation report of two cases and review of the literature.

BACKGROUND: Hypertrophic osteoarthropathy (HOA) is a syndrome characterized by abnormal proliferation of skin and osseous tissue frequently associated with underlying pulmonary disorders. Cardinal features include digital clubbing, periostitis and significant joint and bone pain. A number of recent reports have emerged of HOA and periostitis occurring in association with the antifungal agent voriconazole. METHODS: We present two additional cases of voriconazole-induced HOA and periostitis in lung transplant recipients with a review the medical literature. RESULTS: In both cases, symptoms were painful and severe enough to require opioid medication. Rapid improvement occurred within days of voriconazole cessation. A review of existing literature revealed an additional 17 cases of voriconazole-induced HOA and periostitis in lung transplant patients. CONCLUSION: We highlight the importance of recognizing the association of voriconazole with painful HOA and periostitis in lung transplant patients receiving antifungal therapy. Management of this painful condition involves cessation of voriconazole therapy, which may necessitate alternative anti-fungal drug therapies as well as adjustment of immunosuppressive drug dosage since voriconazole is a strong drug-inducer.

Imaging of the Postoperative Meniscus.

In the postmeniscectomy or meniscal repair setting, there is overlap between expected postoperative change and findings of a re-torn meniscus, particularly increased T1-weighted or proton density signal contacting the articular surface. Protocol selection and accurate diagnosis requires knowledge of meniscal tear treatment, the expected postoperative appearance, and criteria for re-tear. Criteria for meniscal re-tear on MR imaging are high T2-weighted signal reaching the articular surface, abnormal meniscal morphology not explained by the surgery, or a displaced fragment. When MR arthrography is performed, a meniscal tear may or may not exhibit signal intensity as high as that of the intraarticular contrast.

Predicted quadriceps vs. quadrupled hamstring tendon graft size using 3-dimensional MRI.

BACKGROUND: The objective of this study is to (1) compare the predicted cross-sectional area and diameter between quadriceps tendon and quadrupled hamstring autografts, and (2) assess the predicted size of the quadriceps tendon graft in patients with hamstrings that are insufficient for use in ACL reconstruction. METHODS: A retrospective review of 54 knee 3D MRIs was conducted. Quadriceps tendon graft area was defined as a one-centimeter wide area of quadriceps tendon, measured three centimeters above the patella perpendicular to tendon axis. Quadrupled hamstring graft area was defined as double the combined areas of the gracilis and semitendinosus tendon, measured three centimeters above the joint line perpendicular to tendon axis. Pearson correlation was used to compare the quadriceps tendon and quadrupled hamstring grafts. RESULTS: Mean cross-sectional area of quadrupled hamstring and quadriceps tendon grafts were 47.2 mm2 and 84.4 mm2 respectively. A statistically significant positive correlation exists between quadrupled hamstring graft and quadriceps tendon graft cross-sectional area (r = 0.41; p = 0.002). Nine of the 54 patients had predicted quadrupled hamstring grafts deemed insufficient for use in ACL reconstruction (<8 mm diameter). All of these patients had predicted quadriceps tendon graft diameters >8 mm. CONCLUSION: There is a positive correlation between predicted quadriceps tendon and quadrupled hamstring grafts. While 17% of patients in this series had predicted insufficient quadrupled hamstring grafts, all of the patients had predicted quadriceps tendon grafts of sufficient size for ACL reconstruction. Quadriceps tendon grafts are a viable alternative in patients at-risk for insufficient quadrupled hamstring grafts. LEVEL OF EVIDENCE: IV.

Measuring lupus arthritis activity using contrasted high-field MRI. Associations with clinical measures of disease activity and novel patterns of disease.

OBJECTIVE: Arthritis in SLE is poorly described, and there is no objective measure for quantification of arthritis. In this pilot study, we aim to assess the utility of the Rheumatoid Arthritis MRI Scoring System (RAMRIS) for the quantification of lupus arthritis. METHODS: Patients were eligible for entry into the study if they were evaluated at the Medical University of South Carolina Lupus Center and determined by their treating rheumatologist to have active hand arthritis due to SLE. Standard of care lupus activity measures were collected, along with a detailed physical exam. MRIs were obtained using standard musculoskeletal sequences with gadolinium contrast. Semiquantitative scoring of the images used the Outcome Measures in Rheumatology Clinical Trials RAMRIS system. RESULTS: RAMRIS demonstrates large amounts of synovitis, tenosynovitis, bone marrow oedema and erosive disease in only a minority of patients. Some patients were not scored as having any synovitis or tenosynovitis. We describe potential features of lupus arthritis that are not captured in the RAMRIS scores and may be contributing to symptoms. CONCLUSION: Lupus arthritis is an entity separate from rheumatoid arthritis and requires the development of new quantitative methods to describe and quantitate it. MRI findings suggest the inadequacy of a typical lupus musculoskeletal measure including swollen/tender joint counts to assess the level of disease activity.

Heterotopic Ossification Formation Following a Simple Concussion: A Case Report.

CASE: A 19-year-old woman presented with a 3-month history of an enlarging lesion on the proximal aspect of the femur. After imaging studies and a biopsy had been performed, the mass was determined to represent heterotopic ossification (HO). The only known risk factor was a history of concussion. The mass was resected and, as of the 12-month follow-up, had not recurred. CONCLUSION: HO is a potentially serious complication of ossification in soft tissues that can develop secondary to several disease states; it commonly occurs following traumatic brain injury. To our knowledge, this is the only case report that describes HO associated with a concussion and no other risk factors.

Myxofibrosarcoma: First report of myxofibrosarcoma of bone arising at a bone infarct.

Approximately 3300 new primary bone tumors will present to American physicians this year. This small but important group of malignancies has become more defined with developments in pathologic morphology, immunohistochemistry, and molecular studies. As tumor types are better partitioned, their specific characteristics are more readily observed. In this article we present the first reported case of a myxofibrosarcoma of bone developing within a bone infarct. With improved delineation of rarer tumor types, it is expected that additional cases of myxofibrosarcoma of bone will be recognized, potentially arising from a bone infarct. By framing the context, describing the case, and sharing pertinent figures, we hope to facilitate this recognition.

The impact of race on the development of severe heterotopic ossification following acetabular fracture surgery.

OBJECTIVES: To determine the association between race on severe heterotopic ossification (HO) following acetabular fracture surgery. DESIGN: Retrospective case control study. SETTING: Level I university trauma centre. METHODS: Two hundred and fifty-three patients who were surgically treated for acetabular fractures were retrospectively evaluated. Postoperative radiographs were evaluated for HO by a blinded musculoskeletal radiologist, and classified based on a modified Brooker classification. RESULTS: Of the 253 patients that met inclusion and exclusion criteria, 175 (69%) were male and 78 (31%) were female. One hundred and fifty-four (61%) patients were Caucasian, and 99 (39%) were African American (AA). Fifty-five (21%) patients developed severe HO. Of those who developed severe HO, 25 were Caucasian (45%), 30 were African American (55%). Forty-one patients (75%) with severe HO were male, and 14 (25%) were female. No statistical differences (p>0.05) were found between groups in terms of age, days to surgery, GCS at presentation, surgical approach, perioperative HO prophylaxis, or AO/OTA fracture classification. The patient population was then stratified by race, gender, and race/gender. AA were more likely than Caucasians to develop severe HO (odds ratio [OR], 2.24; confidence interval [CI], 1.22-4.11). When gender was considered independent of race, no statistical differences (p>0.05) were observed (OR, 1.40; CI, 0.71-2.75). AA males were much more likely to develop severe HO when compared to Caucasian females (OR, 4.4; CI, 1.38-14.06). CONCLUSION: Race is associated with different rates of severe HO formation following acetabular fracture surgery. AA patients are significantly more likely to develop severe HO following acetabular fracture surgery when compared to Caucasian patients.

Bronchogenic squamous cell carcinoma with soft-tissue metastasis to the hand: an unusual case presentation and review of the literature.

Carcinoma of the lung is the most common lethal form of cancer in both men and women worldwide. Orthopedic manifestations of lung cancer frequently include bony metastasis, most commonly the vertebrae (42%), ribs (20%), and pelvis (18%). Acral metastatic disease is defined as metastasis distal to the elbow or the knee. Metastases to the bones of the hand are extremely rare. Only 0.1% of metastatic disease resulting from any type of carcinoma or sarcoma manifests as metastasis in the hand. There are only a few reports in the literature of soft-tissue or muscular metastasis to the hand from a carcinoma. Of these cases, the majority are caused by metastatic lung carcinoma. However, there are no reports in the literature of metastatic disease of squamous cell origin affecting the soft tissues of the hand. We present a case of a man with known metastatic squamous cell carcinoma of the lung who presented with acral soft-tissue metastatic disease. This report highlights a rare clinical scenario that has not been reported in the literature. This report also highlights a rare but important consideration for clinicians who encounter acral soft-tissue lesions in patients with a history of a primary carcinoma.

Imaging of scleroderma.

Systemic sclerosis is a rare autoimmune condition that affects a variety of organ systems. Knowledge of the imaging features in this patient population is essential in facilitating accurate diagnosis and guiding treatment. Common and rare imaging features of systemic sclerosis are reviewed in this article. Skin, musculoskeletal, pulmonary, cardiac, gastrointestinal, renal, and oral imaging are discussed. Conventional radiography, computed tomography of the chest, echocardiography, enterography, scintigraphy, and panorex dental imaging are reviewed. In addition, the evolving applications of ultrasonography and magnetic resonance imaging to evaluate the musculoskeletal and cardiac features of systemic sclerosis are discussed.

Case report: imaging features in a renal transplant patient with calcineurin inhibitor-induced pain syndrome (CIPS).

Post-transplant distal limb bone marrow edema syndrome or calcineurin inhibitor-induced pain syndrome (CIPS) is generally a self-limiting but debilitating acute pain syndrome that has been reported in 2-14 % of renal transplant recipients. The disease is extensively described in the transplant literature in patients receiving the calcineurin inhibitors cyclosporine and tacrolimus. We present a case of CIPS arising in a patient 73 days after renal allograft, review the imaging findings, and discuss proposed etiologies and differential diagnoses. To the authors' knowledge, CIPS has not been characterized as a distinct entity in the radiology literature.

Insufficiency fracture associated with oncogenic osteomalacia.

Oncogenic osteomalacia is a rare paraneoplastic syndrome of systemic bone demineralization secondary to a tumor-induced dysregulation of phosphorus metabolism. The tumor's low prevalence, small size, and variable location often result in years of muscular weakness and bone pain before diagnosis. With complete treatment, patient's symptoms swiftly dissipate. We report the case of a 63-year-old previously healthy man with a 20-month course of musculoskeletal symptoms before diagnosis and resection of a posterior tibial tumor. Postoperatively, the patient had returned to his previous lifestyle when an insufficiency fracture required prophylactic stabilization.