Michael V. Friedman

Treatment of Metastatic Posterior Vertebral Body Osseous Tumors by Using a Targeted Bipolar Radiofrequency Ablation Device: Technical Note

PURPOSE To evaluate the feasibility of use and safety of a targeted radiofrequency ablation (RFA) device for metastatic posterior vertebral body tumors. MATERIALS AND METHODS This retrospective study was institutional review board approved and HIPAA compliant. Consent was waived for retrospective participation. Fluoroscopic or computed tomography-guided targeted RFA was performed in 26 patients (47 tumors) with painful metastatic posterior vertebral body tumors, some of which were radiation therapy resistant, by using a newly developed spinal tumor ablation system that contains an articulating bipolar extensible electrode. In 14 women and 12 men aged 44-85 years (mean age, 62 years), the most common primary tumor was lung cancer in seven patients (27%) and renal cell carcinoma and sarcoma in five patients each (19%). Other tumors included breast cancer and melanoma in two patients each (8%) and colon cancer, multiple myeloma, neuroendocrine tumor, head and neck squamous cell carcinoma, and unknown primary tumor in one patient each (4%). Ablation was performed with device thermocouples that permitted real-time monitoring of the periphery of the ablation zones to determine ablation size. Sequential postprocedural pain scores were obtained. Thirteen patients underwent follow-up imaging, and one underwent subsequent biopsy of a treated area. A paired two-tailed Student t test was used to evaluate significance of postoperative visual analog scale scores of pain at 1 week and 1 month. RESULTS Four of 26 patients developed transient radicular symptoms after ablation, which resolved with transforaminal blocks. No permanent neurologic injuries resulted from the procedure. Intraprocedural imaging demonstrated that the articulating bipolar instrument could be navigated into the posterior vertebral body tumors with a transpedicular approach. Postablation imaging confirmed necrosis within the ablation zone. Three patients showed progression of disease at the treated levels at follow-up. Systemic therapy was not interrupted to perform the procedures. CONCLUSION Targeted RFA with a newly developed articulating device is both feasible and safe for the treatment of painful posterior vertebral body metastatic tumors.

Inter- and Intraobserver Reliability in the MRI Measurement of the Tibial Tubercle–Trochlear Groove Distance and Trochlea Dysplasia

Background: The tibial tubercle–trochlear groove (TT-TG) distance and trochlear structure have become important radiographic measurements in the evaluation and management of patients with patellar instability. Many orthopaedic surgeons, however, do not have access to musculoskeletal radiologists and therefore must make such measurements independently. Purpose: To determine the intra- and interobserver reliability in the measurement of the TT-TG distance and the determination of the trochlear dysplasia index (TDI) between musculoskeletal radiologists and orthopaedic surgeons. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: Magnetic resonance imaging (MRI) was obtained from 63 patients with the clinical diagnosis of patellar instability (instability group) and from 53 patients without patellar instability (control group). Three radiologists and 2 orthopaedic surgeons blinded to the group assignment independently measured the TT-TG distance and determined the TDI. Each MRI was measured on 2 occasions separated by at least 1 week. Intraclass correlation coefficients (ICCs) were calculated to determine the intra- and interobserver reliability. Results: The instability and control groups were similarly stratified across age, sex, affected knee, athletic level, and body mass index. The mean TT-TG distances were 18.2 ± 5.6 mm and 13.7 ± 5.6 mm for the instability and control groups, respectively (P < .001). The mean TDI for the instability and control groups was 2.1 ± 1.6 mm and 4.6 ± 1.3 mm, respectively (P < .001). There was almost perfect intraobserver reliability for both the TT-TG distance and TDI measurements between the 2 time points for all observers (ICCs: ≥0.86 [TT-TG distance], ≥0.88 [TDI]). The interobserver reliability was also almost perfect between the orthopaedic surgeons and radiologists for both the TT-TG distance (ICC, 0.85 [95% CI, 0.82-0.88]) and TDI (ICC, 0.84 [95% CI, 0.79-0.88]). Conclusion: The results of this study suggest that the intra- and interobserver reliability in the MRI measurement of the TT-TG distance and TDI is high for both orthopaedic surgeons and musculoskeletal radiologists. In addition, the TT-TG distance may be lower than previously thought in patients with patellar instability.

Hip Chondrolysis and Femoral Head Osteonecrosis: A Complication of Periacetabular Cryoablation

PURPOSE To describe a new complication and retrospectively identify the incidence and risk factors for hip chondrolysis and femoral head osteonecrosis associated with percutaneous cryoablation of periacetabular malignancies. MATERIALS AND METHODS In this retrospective study, 45 patients with a total of 113 musculoskeletal lesions were treated by percutaneous image-guided cryoablation between May 2008 and June 2013. Included in the treated population were 10 patients with a total of 12 periacetabular lesions. Clinical and imaging follow-up of at least 2 months was reviewed for evidence of femoral head osteonecrosis or hip chondrolysis. Parametric and nonparametric statistical methods were used to assess patient demographics and treatment technique and parameters on the development of hip chondrolysis/femoral head osteonecrosis. RESULTS Hip chondrolysis/femoral head osteonecrosis developed in 40% of patients (four of 10) and in 33% of treated periacetabular lesions (four of 12). All patients in whom chondrolysis/osteonecrosis developed were women. Needle proximity to the acetabulum (< 5 mm) was a significant predictor of chondrolysis/osteonecrosis development (P = .01). Three of the four patients in whom chondrolysis/osteonecrosis developed have undergone total joint replacement. CONCLUSIONS Periacetabular cryoablation can result in transarticular extension of the ablation zone, which may result in the development of hip chondrolysis and femoral head osteonecrosis. The proximity of the cryoablation probe to the acetabulum is a significant risk factor in the development of this complication.

Traumatic Tear of the Latissimus Dorsi Myotendinous Junction: Case Report of a CrossFit-Related Injury

A case of a latissimus dorsi myotendinous junction strain in an avid CrossFit athlete is presented. The patient developed acute onset right axillary burning and swelling and subsequent palpable pop with weakness while performing a “muscle up.” Magnetic resonance imaging examination demonstrated a high-grade tear of the right latissimus dorsi myotendinous junction approximately 9 cm proximal to its intact humeral insertion. There were no other injuries to the adjacent shoulder girdle structures. Isolated strain of the latissimus dorsi myotendinous junction is a very rare injury with a scarcity of information available regarding its imaging appearance and preferred treatment. This patient was treated conservatively and was able to resume active CrossFit training within 3 months. At 6 months postinjury, he had only a mild residual functional deficit compared with his preinjury level.

Inter-Observer Precision and Physiologic Variability of MRI Landmarks Used to Determine Rotational Alignment in Conventional and Patient-Specific TKA

Preoperative planning for patient-specific guides (PSGs) in total knee arthroplasty (TKA) requires identification of anatomic landmarks on three-dimensional imaging studies. The aim of this study was to assess the accuracy and precision with which landmarks commonly used to determine rotational alignment in TKA can be identified on magnetic resonance imaging (MRI). Two orthopedic surgeons and two musculoskeletal radiologists independently reviewed a sequential series of 114 MRIs of arthritic knees. The magnitude of interobserver variability was high, suggesting an inherent risk of inconsistency when these landmarks are used in PSG fabrication. Additionally, there was a high degree of physiologic variation among patients, indicating that assuming standard relationships among anatomic landmarks when placing TKA components may lead to rotational malalignment relative to each patients native anatomy.

Biopsy of CT-Occult Bone Lesions Using Anatomic Landmarks for CT Guidance

OBJECTIVE The purpose of this study is to evaluate the histopathologic diagnostic yield, sample size, procedural time, and dose-length product (DLP) for the biopsy of CT-occult lesions found at MRI or PET or both. MATERIALS AND METHODS A retrospective review of our radiology information system for biopsies of CT-occult lesions using CT guidance from January 1, 2010, through December 31, 2014, was performed and compared with a selection of CT-guided biopsies of CT-evident bone lesions during the same period. The data were then evaluated for diagnostic yield of histopathologic diagnosis, procedural time, use of sedation medication, DLP, and size of specimens obtained. RESULTS A total of 30 CT-occult biopsies met the inclusion criteria. Twenty-seven of those biopsies had results that were concordant with the patients primary histopathologic diagnosis, imaging findings, and clinical course. In the CT-evident lesion group, concordant histopathologic abnormalities were identified in 27 of 30 patients. There was a statistically significant increase in number of samples obtained for the CT-evident lesions compared with CT-occult lesions. There was no statistically significant difference in total specimen length, DLP, number of CT scans, procedural time, or use of sedation medication between the CT-occult and CT-evident biopsy groups. CONCLUSION Biopsy of CT-occult lesions using anatomic landmarks achieves diagnostic yields similar to those for CT-guided biopsy of CT-evident lesions.

Impact of Shoulder Sonography on Clinical Decision Making

To assess the impact of musculoskeletal shoulder sonography (US) on clinical decision making.

Beyond the greater trochanter: a pictorial review of the pelvic bursae.

PURPOSE Review the MRI appearance of different bursae located throughout the pelvis, including the pertinent osseous and musculotendinous anatomy. MATERIALS AND METHODS Bursae are potential spaces that reduce friction between opposed moving components which can become inflamed, clinically mimicking internal derangement. RESULTS This series illustrates the most common as well as lesser-known pelvic bursae. Common causes of bursitis including overuse, trauma, and infection are presented. CONCLUSION Multiple bursae are located throughout the pelvis. It is important for radiologists to recognize bursitis as a potential etiology of pain and be familiar with their anatomical locations in order to guide appropriate management.

Impact of an Interactive Diagnostic Case Simulator on a Medical Student Radiology Rotation

OBJECTIVE The objective of our study was to assess the short-term impact of adding an interactive simulator to a medical student radiology clerkship. We hypothesized that transitioning students from passive observers to active participants in the reading room would create an appealing and effective learning experience for the current generation of students. MATERIALS AND METHODS An interactive workstation that provided diagnostic simulations of 84 cases selected to maximize exposure to important diagnoses in musculoskeletal (MSK) radiology was created. From February 2015 through July 2016, 83 students on the radiology elective rotated through MSK: 40 in the traditional observational role and 43 with the MSK simulator. At the end of the rotation, all students completed general radiology and MSK-based competency examinations. The students who used the interactive workstation completed a survey about their experience. RESULTS MSK competency scores were significantly better for students who rotated with the interactive workstation compared with students in the traditional observational role (mean scores, 71% and 51%, respectively; p < 0.0001). There was no difference in end-of-rotation general competency scores between the groups (mean, 86% and 85%; p = 0.32). Ninety-one percent of students reported the simulator had at least a moderately positive impact on their radiology experience. All students (100%) reported that learning was improved and recommended establishing workstations for other subspecialties. Twenty-one percent of students reported that their experience using the simulator had a positive impact on considering radiology as a career choice. CONCLUSION Using a reading room-based diagnostic radiology case simulator improves medical student learning, enables self-directed learning, and improves overall experience on the radiology clerkship, positively impacting consideration of radiology as a career.

Eosinophilic granuloma of the sacrum treated with radiation therapy: a case report.

BACKGROUND CONTEXT Eosinophilic granulomas (EGs) of the sacrum have been reported in fewer than 10 patients. Treatment algorithms for these tumors remain poorly defined; there are no reports of treating solitary sacral EG with radiation therapy (RT). PURPOSE This study aimed to describe the presentation, treatment, and outcome of sacral EG in an adult patient with intractable pain and radiculopathy, treated in a novel fashion with RT. STUDY DESIGN/SETTING The study design was a case report from a tertiary cancer referral center. METHODS Patient records, imaging, and pathology were reviewed. RESULTS A 35-year-old man received 20 Gy of radiation to his S1 EG lesion. He subsequently developed vertebra plana of S1 causing symptomatic L5-S1 stenosis, but 15 months after RT treatment was free of pain or tumor recurrence. CONCLUSION Radiation therapy is an effective treatment option for sacral EG causing severe axial pain and neural impingement.