Travis J. Hillen

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.

Imaging of carcinoid tumors: spectrum of findings with pathologic and clinical correlation.

Carcinoid tumors are primary malignant neoplasms that arise from neuroendocrine cells. These cells are located throughout the body, resulting in many possible locations for the development of carcinoid tumor. The most common primary location is the gastrointestinal tract, followed by respiratory and thymic carcinoids. The presentations of these tumors are variable depending on their location, aggressiveness, production of functional peptides, and tendency to invade or metastasize. Carcinoid tumors can be imaged by various modalities including gastrointestinal studies, ultrasound, computed tomography, and magnetic resonance imaging as well as nuclear medicine studies (radioactive octreotide). In this review, we illustrate the spectrum of imaging features of carcinoid tumors in various locations of the human body.

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.

Bony abnormalities of the hip joint: a new comprehensive, reliable and radiation-free measurement method using magnetic resonance imaging

The objective of this study was to develop comprehensive and reliable radiation-free methods to quantify femoral and acetabular morphology using magnetic resonance imaging (MRI). Thirty-two hips [16 subjects, 6 with intra-articular hip disorder (IAHD); 10 controls] were included. A 1.5-T magnetic resonance system was used to obtain three-dimensional fat-suppressed gradient-echo images at the pelvis and distal femora. After acquisition, pelvic images were post-processed to correct for coronal, axial and sagittal rotation. Measurements performed included acetabular version (AV), femoral version (FV), lateral center-edge angle (LCEA), femoral neck angle (FNA) and alpha angle (AA) at 3, 2, 1 and 12 a.m. Two experienced raters, a musculoskeletal radiologist and an orthopedic physical therapist, and a novice rater, a research assistant, completed reliability testing. Raters measured all hips twice with minimum 2 weeks between sessions. Intra-class Correlation Coefficients (ICCs) were used to determine rater reliability; standard error of measurements was reported to estimate the reasonable limits of the expected error in the different raters’ scores. Inter-rater reliability was good to excellent for all raters for AV, FV, FNA and LCEA (ICCs: 0.82–0.98); good to excellent between experienced raters (ICCs: 0.78–0.86) and poor to good between novice and experienced raters (ICCs: 0.23–0.78) for AA. Intra-rater reliability was good to excellent for all raters for AV, FV and FNA (ICCs: 0.93–0.99); for one experienced and novice rater for LCEA (ICCs: 0.84–0.89); moderate to excellent for the experienced raters for AA (ICCs: 0.72-0.89). Intra-rater reliability was poor for the second experienced rater for LCEA (ICC: 0.56), due to a single measurement error and for the novice rater for AA (ICCs: 0.17–0.38). We described MRI methods to comprehensively assess femoral and acetabular morphology. Measurements such as AV, FV and FNA and the LCEA can be made reliably by both experienced and novice raters; however, the AA measurement was reliable only among experienced raters.

Magnetic Resonance Imaging as a Predictor of Return to Play Following Syndesmosis (High) Ankle Sprains in Professional Football Players

Background: Syndesmosis ankle sprains cause greater disability and longer duration of recovery than lateral ankle sprains. Objective: To describe the severity of syndesmosis sprains using several accepted magnetic resonance imaging (MRI) criteria and to assess the interrater reliability of diagnosing syndesmosis injury using these same criteria in professional American football players. Hypothesis: There is a high degree of interrater reliability of MRI findings in American football players with syndesmosis ankle sprains. These radiographic findings will correlate with time lost to injury, indicating severity of the sprain. Study Design: Uncontrolled retrospective review. Methods: Player demographics and time lost to play were recorded among professional football players who had sustained a syndesmosis ankle sprain and underwent standardized ankle MRI. Each image was independently read by 3 blinded musculoskeletal radiologists. Results: Seventeen players met study criteria. There was almost perfect agreement among the radiologists for diagnosing injury to the syndesmotic membrane; substantial agreement for diagnosing injury to the posterior inferior tibiofibular ligament (PITFL) and in determining the proximal extent of syndesmotic edema/injury; but only fair agreement for diagnosing injury to the anterior inferior tibiofibular ligament and in determining the width of syndesmotic separation. There was a significant correlation between the width of syndesmotic separation and time lost, but no significant correlation between individual syndesmotic ligament injury or proximal extent of syndesmotic edema/injury and time lost. Conclusion: While ankle MRI can identify syndesmotic disruption with a high degree of interobserver agreement, no association was demonstrated between the extent of injury on MRI and the time to return to play following a high ankle sprain. Clinical Relevance: In athletes with suspected high ankle sprains, MRI may help confirm diagnosis or suggest alternative diagnoses when the syndesmotic supporting structures are intact. However, the severity of ligamentous and syndesmotic disruption on MRI cannot help predict recovery times.

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.

Triangular Titanium Implants for Minimally Invasive Sacroiliac Joint Fusion: 2-Year Follow-Up from a Prospective Multicenter Trial

Background Sacroiliac joint (SIJ) dysfunction is an underdiagnosed condition. Several published cohorts have reported favorable mid-term outcomes after SIJ fusion using titanium implants placed across the SIJ. Herein we report long-term (24-month) results from a prospective multicenter clinical trial. Methods One hundred and seventy-two subjects at 26 US sites with SI joint dysfunction were enrolled and underwent minimally invasive SI joint fusion with triangular titanium implants. Subjects underwent structured assessments preoperatively and at 1, 3, 6, 12, 18 and 24 months postoperatively, including SIJ pain ratings (0-100 visual analog scale), Oswestry Disability Index (ODI), Short Form-36 (SF-36), EuroQOL-5D (EQ-5D), and patient satisfaction. Adverse events were collected throughout follow-up. All participating patients underwent a high-resolution pelvic CT scan at 1 year. Results Mean subject age was 50.9 years and 69.8% were women. SIJ pain was present for an average of 5.1 years prior to surgical treatment. SIJ pain decreased from 79.8 at baseline to 30.4 at 12 months and remained low at 26.0 at 24 months (p<.0001 for change from baseline). ODI decreased from 55.2 at baseline to 31.5 at 12 months and remained low at 30.9 at 24 months (p<.0001 for change from baseline). Quality of life (SF-36 and EQ-5D) improvements seen at 12 months were sustained at 24 months. The proportion of subjects taking opioids for SIJ or low back pain decreased from 76.2% at baseline to 55.0% at 24 months (p <.0001). To date, 8 subjects (4.7%) have undergone one or more revision SIJ surgeries. 7 device-related adverse events occurred. CT scan at one year showed a high rate (97%) of bone adherence to at least 2 implants on both the iliac and sacral sides with modest rates of bone growth across the SIJ. Conclusions In this study of patients with SIJ dysfunction, minimally invasive SI joint fusion using triangular titanium implants showed marked improvements in pain, disability and quality of life at 2 years. Imaging showed that bone apposition to implants was common but radiographic evidence of intraarticular fusion within the joint may take more than 1 year in many patients. This prospective multicenter clinical trial was approved by local or regional IRBs at each center prior to first patient enrollment. Informed consent with IRB-approved study-specific consent forms was obtained from all patients prior to participation.

Percutaneous Image-Guided Cryoablation of Musculoskeletal Metastases: Pain Palliation and Local Tumor Control.

PURPOSE To evaluate the safety and effectiveness of cryoablation of musculoskeletal metastases in terms of achieving pain palliation and local tumor control. MATERIALS AND METHODS A retrospective review was performed of 92 musculoskeletal metastases in 56 patients treated with percutaneous image-guided cryoablation. Mean age of the cohort was 53.9 y ± 15.1, and cohort included 48% (27/56) men. Median tumor volume was 13.0 cm3 (range, 0.5-577.2 cm3). Indications for treatment included pain palliation (41%; 38/92), local tumor control (15%; 14/92), or both (43%; 40/92). Concurrent cementoplasty was performed after 28% (26/92) of treatments. RESULTS In 78 tumors treated for pain palliation, median pain score before treatment was 8.0. Decreased median pain scores were reported 1 day (6.0; P < .001, n = 62), 1 week (5.0; P < .001, n = 70), 1 month (5.0; P < .001, n = 63), and 3 months (4.5; P = .01, n = 28) after treatment. The median pain score at 6-month follow-up was 7.5 (P = .33, n = 11). Radiographic local tumor control rates were 90% (37/41) at 3 months, 86% (32/37) at 6 months, and 79% (26/33) at 12 months after treatment. The procedural complication rate was 4.3% (4/92). The 3 major complications included 2 cases of hemothorax and 1 transient foot drop. CONCLUSIONS Cryoablation is an effective treatment for palliating painful musculoskeletal metastases and achieving local tumor control.

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.

Multidetector CT Scan in the Evaluation of Chest Pain of Nontraumatic Musculoskeletal Origin

Acute nontraumatic chest pain is a common presenting symptom to the emergency department. Often, it is evaluated by thin-collimation multidetector computed tomography scan (MDCT) using pulmonary embolism, aortic dissection, or coronary artery protocols. The parameters used for these protocols are very similar to those used in protocols for dedicated imaging of the musculoskeletal system. In essence, every MDCT of the chest is also a musculoskeletal examination of the chest. Familiarity with the MDCT-imaging appearance of common musculoskeletal causes of acute nontraumatic chest pain aids in interpretation of the images. This article discusses the MDCT appearance of a number of musculoskeletal causes of chest pain, including those of infectious, rheumatologic, and systemic causes.